xmlregexp.c

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/*
 * regexp.c: generic and extensible Regular Expression engine
 *
 * Basically designed with the purpose of compiling regexps for 
 * the variety of validation/shemas mechanisms now available in
 * XML related specifications these include:
 *    - XML-1.0 DTD validation
 *    - XML Schemas structure part 1
 *    - XML Schemas Datatypes part 2 especially Appendix F
 *    - RELAX-NG/TREX i.e. the counter proposal
 *
 * See Copyright for the status of this software.
 *
 * Daniel Veillard <veillard@redhat.com>
 */

#define IN_LIBXML
#include "libxml.h"

#ifdef LIBXML_REGEXP_ENABLED

/* #define DEBUG_ERR */

#include <stdio.h>
#include <string.h>
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif

#include <libxml/tree.h>
#include <libxml/parserInternals.h>
#include <libxml/xmlregexp.h>
#include <libxml/xmlautomata.h>
#include <libxml/xmlunicode.h>

#ifndef INT_MAX
#define INT_MAX 123456789 /* easy to flag and big enough for our needs */
#endif

/* #define DEBUG_REGEXP_GRAPH */
/* #define DEBUG_REGEXP_EXEC */
/* #define DEBUG_PUSH */
/* #define DEBUG_COMPACTION */

#define MAX_PUSH 10000000

#define ERROR(str)                          \
    ctxt->error = XML_REGEXP_COMPILE_ERROR;             \
    xmlRegexpErrCompile(ctxt, str);
#define NEXT ctxt->cur++
#define CUR (*(ctxt->cur))
#define NXT(index) (ctxt->cur[index])

#define CUR_SCHAR(s, l) xmlStringCurrentChar(NULL, s, &l)
#define NEXTL(l) ctxt->cur += l;
#define XML_REG_STRING_SEPARATOR '|'
/*
 * Need PREV to check on a '-' within a Character Group. May only be used
 * when it's guaranteed that cur is not at the beginning of ctxt->string!
 */
#define PREV (ctxt->cur[-1])

#define TODO                                \
    xmlGenericError(xmlGenericErrorContext,             \
        "Unimplemented block at %s:%d\n",               \
            __FILE__, __LINE__);

/************************************************************************
 *                                  *
 *          Datatypes and structures            *
 *                                  *
 ************************************************************************/

/*
 * Note: the order of the enums below is significant, do not shuffle
 */
typedef enum {
    XML_REGEXP_EPSILON = 1,
    XML_REGEXP_CHARVAL,
    XML_REGEXP_RANGES,
    XML_REGEXP_SUBREG,  /* used for () sub regexps */
    XML_REGEXP_STRING,
    XML_REGEXP_ANYCHAR, /* . */
    XML_REGEXP_ANYSPACE, /* \s */
    XML_REGEXP_NOTSPACE, /* \S */
    XML_REGEXP_INITNAME, /* \l */
    XML_REGEXP_NOTINITNAME, /* \L */
    XML_REGEXP_NAMECHAR, /* \c */
    XML_REGEXP_NOTNAMECHAR, /* \C */
    XML_REGEXP_DECIMAL, /* \d */
    XML_REGEXP_NOTDECIMAL, /* \D */
    XML_REGEXP_REALCHAR, /* \w */
    XML_REGEXP_NOTREALCHAR, /* \W */
    XML_REGEXP_LETTER = 100,
    XML_REGEXP_LETTER_UPPERCASE,
    XML_REGEXP_LETTER_LOWERCASE,
    XML_REGEXP_LETTER_TITLECASE,
    XML_REGEXP_LETTER_MODIFIER,
    XML_REGEXP_LETTER_OTHERS,
    XML_REGEXP_MARK,
    XML_REGEXP_MARK_NONSPACING,
    XML_REGEXP_MARK_SPACECOMBINING,
    XML_REGEXP_MARK_ENCLOSING,
    XML_REGEXP_NUMBER,
    XML_REGEXP_NUMBER_DECIMAL,
    XML_REGEXP_NUMBER_LETTER,
    XML_REGEXP_NUMBER_OTHERS,
    XML_REGEXP_PUNCT,
    XML_REGEXP_PUNCT_CONNECTOR,
    XML_REGEXP_PUNCT_DASH,
    XML_REGEXP_PUNCT_OPEN,
    XML_REGEXP_PUNCT_CLOSE,
    XML_REGEXP_PUNCT_INITQUOTE,
    XML_REGEXP_PUNCT_FINQUOTE,
    XML_REGEXP_PUNCT_OTHERS,
    XML_REGEXP_SEPAR,
    XML_REGEXP_SEPAR_SPACE,
    XML_REGEXP_SEPAR_LINE,
    XML_REGEXP_SEPAR_PARA,
    XML_REGEXP_SYMBOL,
    XML_REGEXP_SYMBOL_MATH,
    XML_REGEXP_SYMBOL_CURRENCY,
    XML_REGEXP_SYMBOL_MODIFIER,
    XML_REGEXP_SYMBOL_OTHERS,
    XML_REGEXP_OTHER,
    XML_REGEXP_OTHER_CONTROL,
    XML_REGEXP_OTHER_FORMAT,
    XML_REGEXP_OTHER_PRIVATE,
    XML_REGEXP_OTHER_NA,
    XML_REGEXP_BLOCK_NAME
} xmlRegAtomType;

typedef enum {
    XML_REGEXP_QUANT_EPSILON = 1,
    XML_REGEXP_QUANT_ONCE,
    XML_REGEXP_QUANT_OPT,
    XML_REGEXP_QUANT_MULT,
    XML_REGEXP_QUANT_PLUS,
    XML_REGEXP_QUANT_ONCEONLY,
    XML_REGEXP_QUANT_ALL,
    XML_REGEXP_QUANT_RANGE
} xmlRegQuantType;

typedef enum {
    XML_REGEXP_START_STATE = 1,
    XML_REGEXP_FINAL_STATE,
    XML_REGEXP_TRANS_STATE,
    XML_REGEXP_SINK_STATE,
    XML_REGEXP_UNREACH_STATE
} xmlRegStateType;

typedef enum {
    XML_REGEXP_MARK_NORMAL = 0,
    XML_REGEXP_MARK_START,
    XML_REGEXP_MARK_VISITED
} xmlRegMarkedType;

typedef struct _xmlRegRange xmlRegRange;
typedef xmlRegRange *xmlRegRangePtr;

struct _xmlRegRange {
    int neg;        /* 0 normal, 1 not, 2 exclude */
    xmlRegAtomType type;
    int start;
    int end;
    xmlChar *blockName;
};

typedef struct _xmlRegAtom xmlRegAtom;
typedef xmlRegAtom *xmlRegAtomPtr;

typedef struct _xmlAutomataState xmlRegState;
typedef xmlRegState *xmlRegStatePtr;

struct _xmlRegAtom {
    int no;
    xmlRegAtomType type;
    xmlRegQuantType quant;
    int min;
    int max;

    void *valuep;
    void *valuep2;
    int neg;
    int codepoint;
    xmlRegStatePtr start;
    xmlRegStatePtr start0;
    xmlRegStatePtr stop;
    int maxRanges;
    int nbRanges;
    xmlRegRangePtr *ranges;
    void *data;
};

typedef struct _xmlRegCounter xmlRegCounter;
typedef xmlRegCounter *xmlRegCounterPtr;

struct _xmlRegCounter {
    int min;
    int max;
};

typedef struct _xmlRegTrans xmlRegTrans;
typedef xmlRegTrans *xmlRegTransPtr;

struct _xmlRegTrans {
    xmlRegAtomPtr atom;
    int to;
    int counter;
    int count;
    int nd;
};

struct _xmlAutomataState {
    xmlRegStateType type;
    xmlRegMarkedType mark;
    xmlRegMarkedType reached;
    int no;
    int maxTrans;
    int nbTrans;
    xmlRegTrans *trans;
    /*  knowing states ponting to us can speed things up */
    int maxTransTo;
    int nbTransTo;
    int *transTo;
};

typedef struct _xmlAutomata xmlRegParserCtxt;
typedef xmlRegParserCtxt *xmlRegParserCtxtPtr;

#define AM_AUTOMATA_RNG 1

struct _xmlAutomata {
    xmlChar *string;
    xmlChar *cur;

    int error;
    int neg;

    xmlRegStatePtr start;
    xmlRegStatePtr end;
    xmlRegStatePtr state;

    xmlRegAtomPtr atom;

    int maxAtoms;
    int nbAtoms;
    xmlRegAtomPtr *atoms;

    int maxStates;
    int nbStates;
    xmlRegStatePtr *states;

    int maxCounters;
    int nbCounters;
    xmlRegCounter *counters;

    int determinist;
    int negs;
    int flags;
};

struct _xmlRegexp {
    xmlChar *string;
    int nbStates;
    xmlRegStatePtr *states;
    int nbAtoms;
    xmlRegAtomPtr *atoms;
    int nbCounters;
    xmlRegCounter *counters;
    int determinist;
    int flags;
    /*
     * That's the compact form for determinists automatas
     */
    int nbstates;
    int *compact;
    void **transdata;
    int nbstrings;
    xmlChar **stringMap;
};

typedef struct _xmlRegExecRollback xmlRegExecRollback;
typedef xmlRegExecRollback *xmlRegExecRollbackPtr;

struct _xmlRegExecRollback {
    xmlRegStatePtr state;/* the current state */
    int index;      /* the index in the input stack */
    int nextbranch; /* the next transition to explore in that state */
    int *counts;    /* save the automata state if it has some */
};

typedef struct _xmlRegInputToken xmlRegInputToken;
typedef xmlRegInputToken *xmlRegInputTokenPtr;

struct _xmlRegInputToken {
    xmlChar *value;
    void *data;
};

struct _xmlRegExecCtxt {
    int status;     /* execution status != 0 indicate an error */
    int determinist;    /* did we find an indeterministic behaviour */
    xmlRegexpPtr comp;  /* the compiled regexp */
    xmlRegExecCallbacks callback;
    void *data;

    xmlRegStatePtr state;/* the current state */
    int transno;    /* the current transition on that state */
    int transcount; /* the number of chars in char counted transitions */

    /*
     * A stack of rollback states
     */
    int maxRollbacks;
    int nbRollbacks;
    xmlRegExecRollback *rollbacks;

    /*
     * The state of the automata if any
     */
    int *counts;

    /*
     * The input stack
     */
    int inputStackMax;
    int inputStackNr;
    int index;
    int *charStack;
    const xmlChar *inputString; /* when operating on characters */
    xmlRegInputTokenPtr inputStack;/* when operating on strings */

    /*
     * error handling
     */
    int errStateNo;     /* the error state number */
    xmlRegStatePtr errState;    /* the error state */
    xmlChar *errString;     /* the string raising the error */
    int *errCounts;     /* counters at the error state */
    int nbPush;
};

#define REGEXP_ALL_COUNTER  0x123456
#define REGEXP_ALL_LAX_COUNTER  0x123457

static void xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top);
static void xmlRegFreeState(xmlRegStatePtr state);
static void xmlRegFreeAtom(xmlRegAtomPtr atom);
static int xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr);
static int xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint);
static int xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint,
                  int neg, int start, int end, const xmlChar *blockName);

void xmlAutomataSetFlags(xmlAutomataPtr am, int flags);

/************************************************************************
 *                                  *
 *      Regexp memory error handler             *
 *                                  *
 ************************************************************************/
static void
xmlRegexpErrMemory(xmlRegParserCtxtPtr ctxt, const char *extra)
{
    const char *regexp = NULL;
    if (ctxt != NULL) {
        regexp = (const char *) ctxt->string;
    ctxt->error = XML_ERR_NO_MEMORY;
    }
    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP,
            XML_ERR_NO_MEMORY, XML_ERR_FATAL, NULL, 0, extra,
            regexp, NULL, 0, 0,
            "Memory allocation failed : %s\n", extra);
}

static void
xmlRegexpErrCompile(xmlRegParserCtxtPtr ctxt, const char *extra)
{
    const char *regexp = NULL;
    int idx = 0;

    if (ctxt != NULL) {
        regexp = (const char *) ctxt->string;
    idx = ctxt->cur - ctxt->string;
    ctxt->error = XML_REGEXP_COMPILE_ERROR;
    }
    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP,
            XML_REGEXP_COMPILE_ERROR, XML_ERR_FATAL, NULL, 0, extra,
            regexp, NULL, idx, 0,
            "failed to compile: %s\n", extra);
}

/************************************************************************
 *                                  *
 *          Allocation/Deallocation             *
 *                                  *
 ************************************************************************/

static int xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt);
static xmlRegexpPtr
xmlRegEpxFromParse(xmlRegParserCtxtPtr ctxt) {
    xmlRegexpPtr ret;

    ret = (xmlRegexpPtr) xmlMalloc(sizeof(xmlRegexp));
    if (ret == NULL) {
    xmlRegexpErrMemory(ctxt, "compiling regexp");
    return(NULL);
    }
    memset(ret, 0, sizeof(xmlRegexp));
    ret->string = ctxt->string;
    ret->nbStates = ctxt->nbStates;
    ret->states = ctxt->states;
    ret->nbAtoms = ctxt->nbAtoms;
    ret->atoms = ctxt->atoms;
    ret->nbCounters = ctxt->nbCounters;
    ret->counters = ctxt->counters;
    ret->determinist = ctxt->determinist;
    ret->flags = ctxt->flags;
    if (ret->determinist == -1) {
        xmlRegexpIsDeterminist(ret);
    }

    if ((ret->determinist != 0) &&
    (ret->nbCounters == 0) &&
    (ctxt->negs == 0) &&
    (ret->atoms != NULL) &&
    (ret->atoms[0] != NULL) &&
    (ret->atoms[0]->type == XML_REGEXP_STRING)) {
    int i, j, nbstates = 0, nbatoms = 0;
    int *stateRemap;
    int *stringRemap;
    int *transitions;
    void **transdata;
    xmlChar **stringMap;
        xmlChar *value;

    /*
     * Switch to a compact representation
     * 1/ counting the effective number of states left
     * 2/ counting the unique number of atoms, and check that
     *    they are all of the string type
     * 3/ build a table state x atom for the transitions
     */

    stateRemap = xmlMalloc(ret->nbStates * sizeof(int));
    if (stateRemap == NULL) {
        xmlRegexpErrMemory(ctxt, "compiling regexp");
        xmlFree(ret);
        return(NULL);
    }
    for (i = 0;i < ret->nbStates;i++) {
        if (ret->states[i] != NULL) {
        stateRemap[i] = nbstates;
        nbstates++;
        } else {
        stateRemap[i] = -1;
        }
    }
#ifdef DEBUG_COMPACTION
    printf("Final: %d states\n", nbstates);
#endif
    stringMap = xmlMalloc(ret->nbAtoms * sizeof(char *));
    if (stringMap == NULL) {
        xmlRegexpErrMemory(ctxt, "compiling regexp");
        xmlFree(stateRemap);
        xmlFree(ret);
        return(NULL);
    }
    stringRemap = xmlMalloc(ret->nbAtoms * sizeof(int));
    if (stringRemap == NULL) {
        xmlRegexpErrMemory(ctxt, "compiling regexp");
        xmlFree(stringMap);
        xmlFree(stateRemap);
        xmlFree(ret);
        return(NULL);
    }
    for (i = 0;i < ret->nbAtoms;i++) {
        if ((ret->atoms[i]->type == XML_REGEXP_STRING) &&
        (ret->atoms[i]->quant == XML_REGEXP_QUANT_ONCE)) {
        value = ret->atoms[i]->valuep;
                for (j = 0;j < nbatoms;j++) {
            if (xmlStrEqual(stringMap[j], value)) {
            stringRemap[i] = j;
            break;
            }
        }
        if (j >= nbatoms) {
            stringRemap[i] = nbatoms;
            stringMap[nbatoms] = xmlStrdup(value);
            if (stringMap[nbatoms] == NULL) {
            for (i = 0;i < nbatoms;i++)
                xmlFree(stringMap[i]);
            xmlFree(stringRemap);
            xmlFree(stringMap);
            xmlFree(stateRemap);
            xmlFree(ret);
            return(NULL);
            }
            nbatoms++;
        }
        } else {
        xmlFree(stateRemap);
        xmlFree(stringRemap);
        for (i = 0;i < nbatoms;i++)
            xmlFree(stringMap[i]);
        xmlFree(stringMap);
        xmlFree(ret);
        return(NULL);
        }
    }
#ifdef DEBUG_COMPACTION
    printf("Final: %d atoms\n", nbatoms);
#endif
    transitions = (int *) xmlMalloc((nbstates + 1) *
                                    (nbatoms + 1) * sizeof(int));
    if (transitions == NULL) {
        xmlFree(stateRemap);
        xmlFree(stringRemap);
        xmlFree(stringMap);
        xmlFree(ret);
        return(NULL);
    }
    memset(transitions, 0, (nbstates + 1) * (nbatoms + 1) * sizeof(int));

    /*
     * Allocate the transition table. The first entry for each
     * state corresponds to the state type.
     */
    transdata = NULL;

    for (i = 0;i < ret->nbStates;i++) {
        int stateno, atomno, targetno, prev;
        xmlRegStatePtr state;
        xmlRegTransPtr trans;

        stateno = stateRemap[i];
        if (stateno == -1)
        continue;
        state = ret->states[i];

        transitions[stateno * (nbatoms + 1)] = state->type;

        for (j = 0;j < state->nbTrans;j++) {
        trans = &(state->trans[j]);
        if ((trans->to == -1) || (trans->atom == NULL))
            continue;
                atomno = stringRemap[trans->atom->no];
        if ((trans->atom->data != NULL) && (transdata == NULL)) {
            transdata = (void **) xmlMalloc(nbstates * nbatoms *
                                        sizeof(void *));
            if (transdata != NULL)
            memset(transdata, 0,
                   nbstates * nbatoms * sizeof(void *));
            else {
            xmlRegexpErrMemory(ctxt, "compiling regexp");
            break;
            }
        }
        targetno = stateRemap[trans->to];
        /*
         * if the same atom can generate transitions to 2 different
         * states then it means the automata is not determinist and
         * the compact form can't be used !
         */
        prev = transitions[stateno * (nbatoms + 1) + atomno + 1];
        if (prev != 0) {
            if (prev != targetno + 1) {
            ret->determinist = 0;
#ifdef DEBUG_COMPACTION
            printf("Indet: state %d trans %d, atom %d to %d : %d to %d\n",
                   i, j, trans->atom->no, trans->to, atomno, targetno);
            printf("       previous to is %d\n", prev);
#endif
            if (transdata != NULL)
                xmlFree(transdata);
            xmlFree(transitions);
            xmlFree(stateRemap);
            xmlFree(stringRemap);
            for (i = 0;i < nbatoms;i++)
                xmlFree(stringMap[i]);
            xmlFree(stringMap);
            goto not_determ;
            }
        } else {
#if 0
            printf("State %d trans %d: atom %d to %d : %d to %d\n",
               i, j, trans->atom->no, trans->to, atomno, targetno);
#endif
            transitions[stateno * (nbatoms + 1) + atomno + 1] =
            targetno + 1; /* to avoid 0 */
            if (transdata != NULL)
            transdata[stateno * nbatoms + atomno] =
                trans->atom->data;
        }
        }
    }
    ret->determinist = 1;
#ifdef DEBUG_COMPACTION
    /*
     * Debug
     */
    for (i = 0;i < nbstates;i++) {
        for (j = 0;j < nbatoms + 1;j++) {
                printf("%02d ", transitions[i * (nbatoms + 1) + j]);
        }
        printf("\n");
    }
    printf("\n");
#endif
    /*
     * Cleanup of the old data
     */
    if (ret->states != NULL) {
        for (i = 0;i < ret->nbStates;i++)
        xmlRegFreeState(ret->states[i]);
        xmlFree(ret->states);
    }
    ret->states = NULL;
    ret->nbStates = 0;
    if (ret->atoms != NULL) {
        for (i = 0;i < ret->nbAtoms;i++)
        xmlRegFreeAtom(ret->atoms[i]);
        xmlFree(ret->atoms);
    }
    ret->atoms = NULL;
    ret->nbAtoms = 0;

    ret->compact = transitions;
    ret->transdata = transdata;
    ret->stringMap = stringMap;
    ret->nbstrings = nbatoms;
    ret->nbstates = nbstates;
    xmlFree(stateRemap);
    xmlFree(stringRemap);
    }
not_determ:
    ctxt->string = NULL;
    ctxt->nbStates = 0;
    ctxt->states = NULL;
    ctxt->nbAtoms = 0;
    ctxt->atoms = NULL;
    ctxt->nbCounters = 0;
    ctxt->counters = NULL;
    return(ret);
}

static xmlRegParserCtxtPtr
xmlRegNewParserCtxt(const xmlChar *string) {
    xmlRegParserCtxtPtr ret;

    ret = (xmlRegParserCtxtPtr) xmlMalloc(sizeof(xmlRegParserCtxt));
    if (ret == NULL)
    return(NULL);
    memset(ret, 0, sizeof(xmlRegParserCtxt));
    if (string != NULL)
    ret->string = xmlStrdup(string);
    ret->cur = ret->string;
    ret->neg = 0;
    ret->negs = 0;
    ret->error = 0;
    ret->determinist = -1;
    return(ret);
}

static xmlRegRangePtr
xmlRegNewRange(xmlRegParserCtxtPtr ctxt,
           int neg, xmlRegAtomType type, int start, int end) {
    xmlRegRangePtr ret;

    ret = (xmlRegRangePtr) xmlMalloc(sizeof(xmlRegRange));
    if (ret == NULL) {
    xmlRegexpErrMemory(ctxt, "allocating range");
    return(NULL);
    }
    ret->neg = neg;
    ret->type = type;
    ret->start = start;
    ret->end = end;
    return(ret);
}

static void
xmlRegFreeRange(xmlRegRangePtr range) {
    if (range == NULL)
    return;

    if (range->blockName != NULL)
    xmlFree(range->blockName);
    xmlFree(range);
}

static xmlRegRangePtr
xmlRegCopyRange(xmlRegParserCtxtPtr ctxt, xmlRegRangePtr range) {
    xmlRegRangePtr ret;

    if (range == NULL)
    return(NULL);

    ret = xmlRegNewRange(ctxt, range->neg, range->type, range->start,
                         range->end);
    if (ret == NULL)
        return(NULL);
    if (range->blockName != NULL) {
    ret->blockName = xmlStrdup(range->blockName);
    if (ret->blockName == NULL) {
        xmlRegexpErrMemory(ctxt, "allocating range");
        xmlRegFreeRange(ret);
        return(NULL);
    }
    }
    return(ret);
}

static xmlRegAtomPtr
xmlRegNewAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomType type) {
    xmlRegAtomPtr ret;

    ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom));
    if (ret == NULL) {
    xmlRegexpErrMemory(ctxt, "allocating atom");
    return(NULL);
    }
    memset(ret, 0, sizeof(xmlRegAtom));
    ret->type = type;
    ret->quant = XML_REGEXP_QUANT_ONCE;
    ret->min = 0;
    ret->max = 0;
    return(ret);
}

static void
xmlRegFreeAtom(xmlRegAtomPtr atom) {
    int i;

    if (atom == NULL)
    return;

    for (i = 0;i < atom->nbRanges;i++)
    xmlRegFreeRange(atom->ranges[i]);
    if (atom->ranges != NULL)
    xmlFree(atom->ranges);
    if ((atom->type == XML_REGEXP_STRING) && (atom->valuep != NULL))
    xmlFree(atom->valuep);
    if ((atom->type == XML_REGEXP_STRING) && (atom->valuep2 != NULL))
    xmlFree(atom->valuep2);
    if ((atom->type == XML_REGEXP_BLOCK_NAME) && (atom->valuep != NULL))
    xmlFree(atom->valuep);
    xmlFree(atom);
}

static xmlRegAtomPtr
xmlRegCopyAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) {
    xmlRegAtomPtr ret;

    ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom));
    if (ret == NULL) {
    xmlRegexpErrMemory(ctxt, "copying atom");
    return(NULL);
    }
    memset(ret, 0, sizeof(xmlRegAtom));
    ret->type = atom->type;
    ret->quant = atom->quant;
    ret->min = atom->min;
    ret->max = atom->max;
    if (atom->nbRanges > 0) {
        int i;

        ret->ranges = (xmlRegRangePtr *) xmlMalloc(sizeof(xmlRegRangePtr) *
                                               atom->nbRanges);
    if (ret->ranges == NULL) {
        xmlRegexpErrMemory(ctxt, "copying atom");
        goto error;
    }
    for (i = 0;i < atom->nbRanges;i++) {
        ret->ranges[i] = xmlRegCopyRange(ctxt, atom->ranges[i]);
        if (ret->ranges[i] == NULL)
            goto error;
        ret->nbRanges = i + 1;
    }
    }
    return(ret);

error:
    xmlRegFreeAtom(ret);
    return(NULL);
}

static xmlRegStatePtr
xmlRegNewState(xmlRegParserCtxtPtr ctxt) {
    xmlRegStatePtr ret;

    ret = (xmlRegStatePtr) xmlMalloc(sizeof(xmlRegState));
    if (ret == NULL) {
    xmlRegexpErrMemory(ctxt, "allocating state");
    return(NULL);
    }
    memset(ret, 0, sizeof(xmlRegState));
    ret->type = XML_REGEXP_TRANS_STATE;
    ret->mark = XML_REGEXP_MARK_NORMAL;
    return(ret);
}

static void
xmlRegFreeState(xmlRegStatePtr state) {
    if (state == NULL)
    return;

    if (state->trans != NULL)
    xmlFree(state->trans);
    if (state->transTo != NULL)
    xmlFree(state->transTo);
    xmlFree(state);
}

static void
xmlRegFreeParserCtxt(xmlRegParserCtxtPtr ctxt) {
    int i;
    if (ctxt == NULL)
    return;

    if (ctxt->string != NULL)
    xmlFree(ctxt->string);
    if (ctxt->states != NULL) {
    for (i = 0;i < ctxt->nbStates;i++)
        xmlRegFreeState(ctxt->states[i]);
    xmlFree(ctxt->states);
    }
    if (ctxt->atoms != NULL) {
    for (i = 0;i < ctxt->nbAtoms;i++)
        xmlRegFreeAtom(ctxt->atoms[i]);
    xmlFree(ctxt->atoms);
    }
    if (ctxt->counters != NULL)
    xmlFree(ctxt->counters);
    xmlFree(ctxt);
}

/************************************************************************
 *                                  *
 *          Display of Data structures          *
 *                                  *
 ************************************************************************/

static void
xmlRegPrintAtomType(FILE *output, xmlRegAtomType type) {
    switch (type) {
        case XML_REGEXP_EPSILON:
        fprintf(output, "epsilon "); break;
        case XML_REGEXP_CHARVAL:
        fprintf(output, "charval "); break;
        case XML_REGEXP_RANGES:
        fprintf(output, "ranges "); break;
        case XML_REGEXP_SUBREG:
        fprintf(output, "subexpr "); break;
        case XML_REGEXP_STRING:
        fprintf(output, "string "); break;
        case XML_REGEXP_ANYCHAR:
        fprintf(output, "anychar "); break;
        case XML_REGEXP_ANYSPACE:
        fprintf(output, "anyspace "); break;
        case XML_REGEXP_NOTSPACE:
        fprintf(output, "notspace "); break;
        case XML_REGEXP_INITNAME:
        fprintf(output, "initname "); break;
        case XML_REGEXP_NOTINITNAME:
        fprintf(output, "notinitname "); break;
        case XML_REGEXP_NAMECHAR:
        fprintf(output, "namechar "); break;
        case XML_REGEXP_NOTNAMECHAR:
        fprintf(output, "notnamechar "); break;
        case XML_REGEXP_DECIMAL:
        fprintf(output, "decimal "); break;
        case XML_REGEXP_NOTDECIMAL:
        fprintf(output, "notdecimal "); break;
        case XML_REGEXP_REALCHAR:
        fprintf(output, "realchar "); break;
        case XML_REGEXP_NOTREALCHAR:
        fprintf(output, "notrealchar "); break;
        case XML_REGEXP_LETTER:
            fprintf(output, "LETTER "); break;
        case XML_REGEXP_LETTER_UPPERCASE:
            fprintf(output, "LETTER_UPPERCASE "); break;
        case XML_REGEXP_LETTER_LOWERCASE:
            fprintf(output, "LETTER_LOWERCASE "); break;
        case XML_REGEXP_LETTER_TITLECASE:
            fprintf(output, "LETTER_TITLECASE "); break;
        case XML_REGEXP_LETTER_MODIFIER:
            fprintf(output, "LETTER_MODIFIER "); break;
        case XML_REGEXP_LETTER_OTHERS:
            fprintf(output, "LETTER_OTHERS "); break;
        case XML_REGEXP_MARK:
            fprintf(output, "MARK "); break;
        case XML_REGEXP_MARK_NONSPACING:
            fprintf(output, "MARK_NONSPACING "); break;
        case XML_REGEXP_MARK_SPACECOMBINING:
            fprintf(output, "MARK_SPACECOMBINING "); break;
        case XML_REGEXP_MARK_ENCLOSING:
            fprintf(output, "MARK_ENCLOSING "); break;
        case XML_REGEXP_NUMBER:
            fprintf(output, "NUMBER "); break;
        case XML_REGEXP_NUMBER_DECIMAL:
            fprintf(output, "NUMBER_DECIMAL "); break;
        case XML_REGEXP_NUMBER_LETTER:
            fprintf(output, "NUMBER_LETTER "); break;
        case XML_REGEXP_NUMBER_OTHERS:
            fprintf(output, "NUMBER_OTHERS "); break;
        case XML_REGEXP_PUNCT:
            fprintf(output, "PUNCT "); break;
        case XML_REGEXP_PUNCT_CONNECTOR:
            fprintf(output, "PUNCT_CONNECTOR "); break;
        case XML_REGEXP_PUNCT_DASH:
            fprintf(output, "PUNCT_DASH "); break;
        case XML_REGEXP_PUNCT_OPEN:
            fprintf(output, "PUNCT_OPEN "); break;
        case XML_REGEXP_PUNCT_CLOSE:
            fprintf(output, "PUNCT_CLOSE "); break;
        case XML_REGEXP_PUNCT_INITQUOTE:
            fprintf(output, "PUNCT_INITQUOTE "); break;
        case XML_REGEXP_PUNCT_FINQUOTE:
            fprintf(output, "PUNCT_FINQUOTE "); break;
        case XML_REGEXP_PUNCT_OTHERS:
            fprintf(output, "PUNCT_OTHERS "); break;
        case XML_REGEXP_SEPAR:
            fprintf(output, "SEPAR "); break;
        case XML_REGEXP_SEPAR_SPACE:
            fprintf(output, "SEPAR_SPACE "); break;
        case XML_REGEXP_SEPAR_LINE:
            fprintf(output, "SEPAR_LINE "); break;
        case XML_REGEXP_SEPAR_PARA:
            fprintf(output, "SEPAR_PARA "); break;
        case XML_REGEXP_SYMBOL:
            fprintf(output, "SYMBOL "); break;
        case XML_REGEXP_SYMBOL_MATH:
            fprintf(output, "SYMBOL_MATH "); break;
        case XML_REGEXP_SYMBOL_CURRENCY:
            fprintf(output, "SYMBOL_CURRENCY "); break;
        case XML_REGEXP_SYMBOL_MODIFIER:
            fprintf(output, "SYMBOL_MODIFIER "); break;
        case XML_REGEXP_SYMBOL_OTHERS:
            fprintf(output, "SYMBOL_OTHERS "); break;
        case XML_REGEXP_OTHER:
            fprintf(output, "OTHER "); break;
        case XML_REGEXP_OTHER_CONTROL:
            fprintf(output, "OTHER_CONTROL "); break;
        case XML_REGEXP_OTHER_FORMAT:
            fprintf(output, "OTHER_FORMAT "); break;
        case XML_REGEXP_OTHER_PRIVATE:
            fprintf(output, "OTHER_PRIVATE "); break;
        case XML_REGEXP_OTHER_NA:
            fprintf(output, "OTHER_NA "); break;
        case XML_REGEXP_BLOCK_NAME:
        fprintf(output, "BLOCK "); break;
    }
}

static void
xmlRegPrintQuantType(FILE *output, xmlRegQuantType type) {
    switch (type) {
        case XML_REGEXP_QUANT_EPSILON:
        fprintf(output, "epsilon "); break;
        case XML_REGEXP_QUANT_ONCE:
        fprintf(output, "once "); break;
        case XML_REGEXP_QUANT_OPT:
        fprintf(output, "? "); break;
        case XML_REGEXP_QUANT_MULT:
        fprintf(output, "* "); break;
        case XML_REGEXP_QUANT_PLUS:
        fprintf(output, "+ "); break;
    case XML_REGEXP_QUANT_RANGE:
        fprintf(output, "range "); break;
    case XML_REGEXP_QUANT_ONCEONLY:
        fprintf(output, "onceonly "); break;
    case XML_REGEXP_QUANT_ALL:
        fprintf(output, "all "); break;
    }
}
static void
xmlRegPrintRange(FILE *output, xmlRegRangePtr range) {
    fprintf(output, "  range: ");
    if (range->neg)
    fprintf(output, "negative ");
    xmlRegPrintAtomType(output, range->type);
    fprintf(output, "%c - %c\n", range->start, range->end);
}

static void
xmlRegPrintAtom(FILE *output, xmlRegAtomPtr atom) {
    fprintf(output, " atom: ");
    if (atom == NULL) {
    fprintf(output, "NULL\n");
    return;
    }
    if (atom->neg)
        fprintf(output, "not ");
    xmlRegPrintAtomType(output, atom->type);
    xmlRegPrintQuantType(output, atom->quant);
    if (atom->quant == XML_REGEXP_QUANT_RANGE)
    fprintf(output, "%d-%d ", atom->min, atom->max);
    if (atom->type == XML_REGEXP_STRING)
    fprintf(output, "'%s' ", (char *) atom->valuep);
    if (atom->type == XML_REGEXP_CHARVAL)
    fprintf(output, "char %c\n", atom->codepoint);
    else if (atom->type == XML_REGEXP_RANGES) {
    int i;
    fprintf(output, "%d entries\n", atom->nbRanges);
    for (i = 0; i < atom->nbRanges;i++)
        xmlRegPrintRange(output, atom->ranges[i]);
    } else if (atom->type == XML_REGEXP_SUBREG) {
    fprintf(output, "start %d end %d\n", atom->start->no, atom->stop->no);
    } else {
    fprintf(output, "\n");
    }
}

static void
xmlRegPrintTrans(FILE *output, xmlRegTransPtr trans) {
    fprintf(output, "  trans: ");
    if (trans == NULL) {
    fprintf(output, "NULL\n");
    return;
    }
    if (trans->to < 0) {
    fprintf(output, "removed\n");
    return;
    }
    if (trans->nd != 0) {
    if (trans->nd == 2)
        fprintf(output, "last not determinist, ");
    else
        fprintf(output, "not determinist, ");
    }
    if (trans->counter >= 0) {
    fprintf(output, "counted %d, ", trans->counter);
    }
    if (trans->count == REGEXP_ALL_COUNTER) {
    fprintf(output, "all transition, ");
    } else if (trans->count >= 0) {
    fprintf(output, "count based %d, ", trans->count);
    }
    if (trans->atom == NULL) {
    fprintf(output, "epsilon to %d\n", trans->to);
    return;
    }
    if (trans->atom->type == XML_REGEXP_CHARVAL)
    fprintf(output, "char %c ", trans->atom->codepoint);
    fprintf(output, "atom %d, to %d\n", trans->atom->no, trans->to);
}
    
static void
xmlRegPrintState(FILE *output, xmlRegStatePtr state) {
    int i;

    fprintf(output, " state: ");
    if (state == NULL) {
    fprintf(output, "NULL\n");
    return;
    }
    if (state->type == XML_REGEXP_START_STATE)
    fprintf(output, "START ");
    if (state->type == XML_REGEXP_FINAL_STATE)
    fprintf(output, "FINAL ");
    
    fprintf(output, "%d, %d transitions:\n", state->no, state->nbTrans);
    for (i = 0;i < state->nbTrans; i++) {
    xmlRegPrintTrans(output, &(state->trans[i]));
    }
}

#ifdef DEBUG_REGEXP_GRAPH
static void
xmlRegPrintCtxt(FILE *output, xmlRegParserCtxtPtr ctxt) {
    int i;

    fprintf(output, " ctxt: ");
    if (ctxt == NULL) {
    fprintf(output, "NULL\n");
    return;
    }
    fprintf(output, "'%s' ", ctxt->string);
    if (ctxt->error)
    fprintf(output, "error ");
    if (ctxt->neg)
    fprintf(output, "neg ");
    fprintf(output, "\n");
    fprintf(output, "%d atoms:\n", ctxt->nbAtoms);
    for (i = 0;i < ctxt->nbAtoms; i++) {
    fprintf(output, " %02d ", i);
    xmlRegPrintAtom(output, ctxt->atoms[i]);
    }
    if (ctxt->atom != NULL) {
    fprintf(output, "current atom:\n");
    xmlRegPrintAtom(output, ctxt->atom);
    }
    fprintf(output, "%d states:", ctxt->nbStates);
    if (ctxt->start != NULL)
    fprintf(output, " start: %d", ctxt->start->no);
    if (ctxt->end != NULL)
    fprintf(output, " end: %d", ctxt->end->no);
    fprintf(output, "\n");
    for (i = 0;i < ctxt->nbStates; i++) {
    xmlRegPrintState(output, ctxt->states[i]);
    }
    fprintf(output, "%d counters:\n", ctxt->nbCounters);
    for (i = 0;i < ctxt->nbCounters; i++) {
    fprintf(output, " %d: min %d max %d\n", i, ctxt->counters[i].min,
                                        ctxt->counters[i].max);
    }
}
#endif

/************************************************************************
 *                                  *
 *       Finite Automata structures manipulations       *
 *                                  *
 ************************************************************************/

static void 
xmlRegAtomAddRange(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom,
               int neg, xmlRegAtomType type, int start, int end,
           xmlChar *blockName) {
    xmlRegRangePtr range;

    if (atom == NULL) {
    ERROR("add range: atom is NULL");
    return;
    }
    if (atom->type != XML_REGEXP_RANGES) {
    ERROR("add range: atom is not ranges");
    return;
    }
    if (atom->maxRanges == 0) {
    atom->maxRanges = 4;
    atom->ranges = (xmlRegRangePtr *) xmlMalloc(atom->maxRanges *
                                     sizeof(xmlRegRangePtr));
    if (atom->ranges == NULL) {
        xmlRegexpErrMemory(ctxt, "adding ranges");
        atom->maxRanges = 0;
        return;
    }
    } else if (atom->nbRanges >= atom->maxRanges) {
    xmlRegRangePtr *tmp;
    atom->maxRanges *= 2;
    tmp = (xmlRegRangePtr *) xmlRealloc(atom->ranges, atom->maxRanges *
                                     sizeof(xmlRegRangePtr));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "adding ranges");
        atom->maxRanges /= 2;
        return;
    }
    atom->ranges = tmp;
    }
    range = xmlRegNewRange(ctxt, neg, type, start, end);
    if (range == NULL)
    return;
    range->blockName = blockName;
    atom->ranges[atom->nbRanges++] = range;
    
}

static int
xmlRegGetCounter(xmlRegParserCtxtPtr ctxt) {
    if (ctxt->maxCounters == 0) {
    ctxt->maxCounters = 4;
    ctxt->counters = (xmlRegCounter *) xmlMalloc(ctxt->maxCounters *
                                     sizeof(xmlRegCounter));
    if (ctxt->counters == NULL) {
        xmlRegexpErrMemory(ctxt, "allocating counter");
        ctxt->maxCounters = 0;
        return(-1);
    }
    } else if (ctxt->nbCounters >= ctxt->maxCounters) {
    xmlRegCounter *tmp;
    ctxt->maxCounters *= 2;
    tmp = (xmlRegCounter *) xmlRealloc(ctxt->counters, ctxt->maxCounters *
                                   sizeof(xmlRegCounter));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "allocating counter");
        ctxt->maxCounters /= 2;
        return(-1);
    }
    ctxt->counters = tmp;
    }
    ctxt->counters[ctxt->nbCounters].min = -1;
    ctxt->counters[ctxt->nbCounters].max = -1;
    return(ctxt->nbCounters++);
}

static int 
xmlRegAtomPush(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) {
    if (atom == NULL) {
    ERROR("atom push: atom is NULL");
    return(-1);
    }
    if (ctxt->maxAtoms == 0) {
    ctxt->maxAtoms = 4;
    ctxt->atoms = (xmlRegAtomPtr *) xmlMalloc(ctxt->maxAtoms *
                                     sizeof(xmlRegAtomPtr));
    if (ctxt->atoms == NULL) {
        xmlRegexpErrMemory(ctxt, "pushing atom");
        ctxt->maxAtoms = 0;
        return(-1);
    }
    } else if (ctxt->nbAtoms >= ctxt->maxAtoms) {
    xmlRegAtomPtr *tmp;
    ctxt->maxAtoms *= 2;
    tmp = (xmlRegAtomPtr *) xmlRealloc(ctxt->atoms, ctxt->maxAtoms *
                                     sizeof(xmlRegAtomPtr));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "allocating counter");
        ctxt->maxAtoms /= 2;
        return(-1);
    }
    ctxt->atoms = tmp;
    }
    atom->no = ctxt->nbAtoms;
    ctxt->atoms[ctxt->nbAtoms++] = atom;
    return(0);
}

static void 
xmlRegStateAddTransTo(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr target,
                      int from) {
    if (target->maxTransTo == 0) {
    target->maxTransTo = 8;
    target->transTo = (int *) xmlMalloc(target->maxTransTo *
                                     sizeof(int));
    if (target->transTo == NULL) {
        xmlRegexpErrMemory(ctxt, "adding transition");
        target->maxTransTo = 0;
        return;
    }
    } else if (target->nbTransTo >= target->maxTransTo) {
    int *tmp;
    target->maxTransTo *= 2;
    tmp = (int *) xmlRealloc(target->transTo, target->maxTransTo *
                                     sizeof(int));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "adding transition");
        target->maxTransTo /= 2;
        return;
    }
    target->transTo = tmp;
    }
    target->transTo[target->nbTransTo] = from;
    target->nbTransTo++;
}

static void 
xmlRegStateAddTrans(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state,
                xmlRegAtomPtr atom, xmlRegStatePtr target,
            int counter, int count) {

    int nrtrans;

    if (state == NULL) {
    ERROR("add state: state is NULL");
    return;
    }
    if (target == NULL) {
    ERROR("add state: target is NULL");
    return;
    }
    /*
     * Other routines follow the philosophy 'When in doubt, add a transition'
     * so we check here whether such a transition is already present and, if
     * so, silently ignore this request.
     */

    for (nrtrans = state->nbTrans - 1; nrtrans >= 0; nrtrans--) {
    xmlRegTransPtr trans = &(state->trans[nrtrans]);
    if ((trans->atom == atom) &&
        (trans->to == target->no) &&
        (trans->counter == counter) &&
        (trans->count == count)) {
#ifdef DEBUG_REGEXP_GRAPH
        printf("Ignoring duplicate transition from %d to %d\n",
            state->no, target->no);
#endif
        return;
    }
    }

    if (state->maxTrans == 0) {
    state->maxTrans = 8;
    state->trans = (xmlRegTrans *) xmlMalloc(state->maxTrans *
                                     sizeof(xmlRegTrans));
    if (state->trans == NULL) {
        xmlRegexpErrMemory(ctxt, "adding transition");
        state->maxTrans = 0;
        return;
    }
    } else if (state->nbTrans >= state->maxTrans) {
    xmlRegTrans *tmp;
    state->maxTrans *= 2;
    tmp = (xmlRegTrans *) xmlRealloc(state->trans, state->maxTrans *
                                     sizeof(xmlRegTrans));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "adding transition");
        state->maxTrans /= 2;
        return;
    }
    state->trans = tmp;
    }
#ifdef DEBUG_REGEXP_GRAPH
    printf("Add trans from %d to %d ", state->no, target->no);
    if (count == REGEXP_ALL_COUNTER)
    printf("all transition\n");
    else if (count >= 0)
    printf("count based %d\n", count);
    else if (counter >= 0)
    printf("counted %d\n", counter);
    else if (atom == NULL)
    printf("epsilon transition\n");
    else if (atom != NULL) 
        xmlRegPrintAtom(stdout, atom);
#endif

    state->trans[state->nbTrans].atom = atom;
    state->trans[state->nbTrans].to = target->no;
    state->trans[state->nbTrans].counter = counter;
    state->trans[state->nbTrans].count = count;
    state->trans[state->nbTrans].nd = 0;
    state->nbTrans++;
    xmlRegStateAddTransTo(ctxt, target, state->no);
}

static int
xmlRegStatePush(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state) {
    if (state == NULL) return(-1);
    if (ctxt->maxStates == 0) {
    ctxt->maxStates = 4;
    ctxt->states = (xmlRegStatePtr *) xmlMalloc(ctxt->maxStates *
                                     sizeof(xmlRegStatePtr));
    if (ctxt->states == NULL) {
        xmlRegexpErrMemory(ctxt, "adding state");
        ctxt->maxStates = 0;
        return(-1);
    }
    } else if (ctxt->nbStates >= ctxt->maxStates) {
    xmlRegStatePtr *tmp;
    ctxt->maxStates *= 2;
    tmp = (xmlRegStatePtr *) xmlRealloc(ctxt->states, ctxt->maxStates *
                                     sizeof(xmlRegStatePtr));
    if (tmp == NULL) {
        xmlRegexpErrMemory(ctxt, "adding state");
        ctxt->maxStates /= 2;
        return(-1);
    }
    ctxt->states = tmp;
    }
    state->no = ctxt->nbStates;
    ctxt->states[ctxt->nbStates++] = state;
    return(0);
}

static void
xmlFAGenerateAllTransition(xmlRegParserCtxtPtr ctxt,
               xmlRegStatePtr from, xmlRegStatePtr to,
               int lax) {
    if (to == NULL) {
    to = xmlRegNewState(ctxt);
    xmlRegStatePush(ctxt, to);
    ctxt->state = to;
    }
    if (lax)
    xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_LAX_COUNTER);
    else
    xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_COUNTER);
}

static void
xmlFAGenerateEpsilonTransition(xmlRegParserCtxtPtr ctxt,
                   xmlRegStatePtr from, xmlRegStatePtr to) {
    if (to == NULL) {
    to = xmlRegNewState(ctxt);
    xmlRegStatePush(ctxt, to);
    ctxt->state = to;
    }
    xmlRegStateAddTrans(ctxt, from, NULL, to, -1, -1);
}

static void
xmlFAGenerateCountedEpsilonTransition(xmlRegParserCtxtPtr ctxt,
        xmlRegStatePtr from, xmlRegStatePtr to, int counter) {
    if (to == NULL) {
    to = xmlRegNewState(ctxt);
    xmlRegStatePush(ctxt, to);
    ctxt->state = to;
    }
    xmlRegStateAddTrans(ctxt, from, NULL, to, counter, -1);
}

static void
xmlFAGenerateCountedTransition(xmlRegParserCtxtPtr ctxt,
        xmlRegStatePtr from, xmlRegStatePtr to, int counter) {
    if (to == NULL) {
    to = xmlRegNewState(ctxt);
    xmlRegStatePush(ctxt, to);
    ctxt->state = to;
    }
    xmlRegStateAddTrans(ctxt, from, NULL, to, -1, counter);
}

static int
xmlFAGenerateTransitions(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from,
                     xmlRegStatePtr to, xmlRegAtomPtr atom) {
    xmlRegStatePtr end;

    if (atom == NULL) {
    ERROR("genrate transition: atom == NULL");
    return(-1);
    }
    if (atom->type == XML_REGEXP_SUBREG) {
    /*
     * this is a subexpression handling one should not need to
     * create a new node except for XML_REGEXP_QUANT_RANGE.
     */
    if (xmlRegAtomPush(ctxt, atom) < 0) {
        return(-1);
    }
    if ((to != NULL) && (atom->stop != to) &&
        (atom->quant != XML_REGEXP_QUANT_RANGE)) {
        /*
         * Generate an epsilon transition to link to the target
         */
        xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to);
#ifdef DV
    } else if ((to == NULL) && (atom->quant != XML_REGEXP_QUANT_RANGE) && 
           (atom->quant != XML_REGEXP_QUANT_ONCE)) {
        to = xmlRegNewState(ctxt);
        xmlRegStatePush(ctxt, to);
        ctxt->state = to;
        xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to);
#endif
    }
    switch (atom->quant) {
        case XML_REGEXP_QUANT_OPT:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        /*
         * transition done to the state after end of atom.
         *      1. set transition from atom start to new state
         *      2. set transition from atom end to this state. 
         */
                if (to == NULL) {
                    xmlFAGenerateEpsilonTransition(ctxt, atom->start, 0);
                    xmlFAGenerateEpsilonTransition(ctxt, atom->stop,
                                                   ctxt->state);
                } else {
                    xmlFAGenerateEpsilonTransition(ctxt, atom->start, to);
                }
        break;
        case XML_REGEXP_QUANT_MULT:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        xmlFAGenerateEpsilonTransition(ctxt, atom->start, atom->stop);
        xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start);
        break;
        case XML_REGEXP_QUANT_PLUS:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start);
        break;
        case XML_REGEXP_QUANT_RANGE: {
        int counter;
        xmlRegStatePtr inter, newstate;

        /*
         * create the final state now if needed
         */
        if (to != NULL) {
            newstate = to;
        } else {
            newstate = xmlRegNewState(ctxt);
            xmlRegStatePush(ctxt, newstate);
        }

        /*
         * The principle here is to use counted transition
         * to avoid explosion in the number of states in the
         * graph. This is clearly more complex but should not
         * be exploitable at runtime.
         */
        if ((atom->min == 0) && (atom->start0 == NULL)) {
            xmlRegAtomPtr copy;
            /*
             * duplicate a transition based on atom to count next
             * occurences after 1. We cannot loop to atom->start
             * directly because we need an epsilon transition to 
             * newstate.
             */
             /* ???? For some reason it seems we never reach that
                case, I suppose this got optimized out before when
            building the automata */
            copy = xmlRegCopyAtom(ctxt, atom);
            if (copy == NULL)
                return(-1);
            copy->quant = XML_REGEXP_QUANT_ONCE;
            copy->min = 0;
            copy->max = 0;

            if (xmlFAGenerateTransitions(ctxt, atom->start, NULL, copy)
                < 0)
            return(-1);
            inter = ctxt->state;
            counter = xmlRegGetCounter(ctxt);
            ctxt->counters[counter].min = atom->min - 1;
            ctxt->counters[counter].max = atom->max - 1;
            /* count the number of times we see it again */
            xmlFAGenerateCountedEpsilonTransition(ctxt, inter,
                           atom->stop, counter);
            /* allow a way out based on the count */
            xmlFAGenerateCountedTransition(ctxt, inter,
                                       newstate, counter);
            /* and also allow a direct exit for 0 */
            xmlFAGenerateEpsilonTransition(ctxt, atom->start,
                                           newstate);
        } else {
            /*
             * either we need the atom at least once or there
             * is an atom->start0 allowing to easilly plug the
             * epsilon transition.
             */
            counter = xmlRegGetCounter(ctxt);
            ctxt->counters[counter].min = atom->min - 1;
            ctxt->counters[counter].max = atom->max - 1;
            /* count the number of times we see it again */
            xmlFAGenerateCountedEpsilonTransition(ctxt, atom->stop,
                           atom->start, counter);
            /* allow a way out based on the count */
            xmlFAGenerateCountedTransition(ctxt, atom->stop,
                                       newstate, counter);
            /* and if needed allow a direct exit for 0 */
            if (atom->min == 0)
            xmlFAGenerateEpsilonTransition(ctxt, atom->start0,
                               newstate);

        }
        atom->min = 0;
        atom->max = 0;
        atom->quant = XML_REGEXP_QUANT_ONCE;
        ctxt->state = newstate;
        }
        default:
        break;
    }
    return(0);
    } 
    if ((atom->min == 0) && (atom->max == 0) &&
               (atom->quant == XML_REGEXP_QUANT_RANGE)) {
        /*
     * we can discard the atom and generate an epsilon transition instead
     */
    if (to == NULL) {
        to = xmlRegNewState(ctxt);
        if (to != NULL)
        xmlRegStatePush(ctxt, to);
        else {
        return(-1);
        }
    }
    xmlFAGenerateEpsilonTransition(ctxt, from, to);
    ctxt->state = to;
    xmlRegFreeAtom(atom);
    return(0);
    }
    if (to == NULL) {
    to = xmlRegNewState(ctxt);
    if (to != NULL)
        xmlRegStatePush(ctxt, to);
    else {
        return(-1);
    }
    } 
    end = to;
    if ((atom->quant == XML_REGEXP_QUANT_MULT) || 
        (atom->quant == XML_REGEXP_QUANT_PLUS)) {
    /*
     * Do not pollute the target state by adding transitions from
     * it as it is likely to be the shared target of multiple branches.
     * So isolate with an epsilon transition.
     */
        xmlRegStatePtr tmp;
    
    tmp = xmlRegNewState(ctxt);
    if (tmp != NULL)
        xmlRegStatePush(ctxt, tmp);
    else {
        return(-1);
    }
    xmlFAGenerateEpsilonTransition(ctxt, tmp, to);
    to = tmp;
    }
    if (xmlRegAtomPush(ctxt, atom) < 0) {
    return(-1);
    }
    xmlRegStateAddTrans(ctxt, from, atom, to, -1, -1);
    ctxt->state = end;
    switch (atom->quant) {
    case XML_REGEXP_QUANT_OPT:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        xmlFAGenerateEpsilonTransition(ctxt, from, to);
        break;
    case XML_REGEXP_QUANT_MULT:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        xmlFAGenerateEpsilonTransition(ctxt, from, to);
        xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1);
        break;
    case XML_REGEXP_QUANT_PLUS:
        atom->quant = XML_REGEXP_QUANT_ONCE;
        xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1);
        break;
    case XML_REGEXP_QUANT_RANGE: 
#if DV_test
        if (atom->min == 0) {
        xmlFAGenerateEpsilonTransition(ctxt, from, to);
        }
#endif
        break;
    default:
        break;
    }
    return(0);
}

static void
xmlFAReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int fromnr,
                          int tonr, int counter) {
    int transnr;
    xmlRegStatePtr from;
    xmlRegStatePtr to;

#ifdef DEBUG_REGEXP_GRAPH
    printf("xmlFAReduceEpsilonTransitions(%d, %d)\n", fromnr, tonr);
#endif
    from = ctxt->states[fromnr];
    if (from == NULL)
    return;
    to = ctxt->states[tonr];
    if (to == NULL)
    return;
    if ((to->mark == XML_REGEXP_MARK_START) ||
    (to->mark == XML_REGEXP_MARK_VISITED))
    return;

    to->mark = XML_REGEXP_MARK_VISITED;
    if (to->type == XML_REGEXP_FINAL_STATE) {
#ifdef DEBUG_REGEXP_GRAPH
    printf("State %d is final, so %d becomes final\n", tonr, fromnr);
#endif
    from->type = XML_REGEXP_FINAL_STATE;
    }
    for (transnr = 0;transnr < to->nbTrans;transnr++) {
        if (to->trans[transnr].to < 0)
        continue;
    if (to->trans[transnr].atom == NULL) {
        /*
         * Don't remove counted transitions
         * Don't loop either
         */
        if (to->trans[transnr].to != fromnr) {
        if (to->trans[transnr].count >= 0) {
            int newto = to->trans[transnr].to;

            xmlRegStateAddTrans(ctxt, from, NULL,
                    ctxt->states[newto], 
                    -1, to->trans[transnr].count);
        } else {
#ifdef DEBUG_REGEXP_GRAPH
            printf("Found epsilon trans %d from %d to %d\n",
               transnr, tonr, to->trans[transnr].to);
#endif
            if (to->trans[transnr].counter >= 0) {
            xmlFAReduceEpsilonTransitions(ctxt, fromnr,
                          to->trans[transnr].to,
                          to->trans[transnr].counter);
            } else {
            xmlFAReduceEpsilonTransitions(ctxt, fromnr,
                          to->trans[transnr].to,
                          counter);
            }
        }
        }
    } else {
        int newto = to->trans[transnr].to;

        if (to->trans[transnr].counter >= 0) {
        xmlRegStateAddTrans(ctxt, from, to->trans[transnr].atom, 
                    ctxt->states[newto], 
                    to->trans[transnr].counter, -1);
        } else {
        xmlRegStateAddTrans(ctxt, from, to->trans[transnr].atom, 
                    ctxt->states[newto], counter, -1);
        }
    }
    }
    to->mark = XML_REGEXP_MARK_NORMAL;
}

static void
xmlFAEliminateSimpleEpsilonTransitions(xmlRegParserCtxtPtr ctxt) {
    int statenr, i, j, newto;
    xmlRegStatePtr state, tmp;

    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if (state == NULL)
        continue;
    if (state->nbTrans != 1)
        continue;
    if (state->type == XML_REGEXP_UNREACH_STATE)
        continue;
    /* is the only transition out a basic transition */
    if ((state->trans[0].atom == NULL) &&
        (state->trans[0].to >= 0) &&
        (state->trans[0].to != statenr) &&
        (state->trans[0].counter < 0) &&
        (state->trans[0].count < 0)) {
        newto = state->trans[0].to;

            if (state->type == XML_REGEXP_START_STATE) {
#ifdef DEBUG_REGEXP_GRAPH
        printf("Found simple epsilon trans from start %d to %d\n",
               statenr, newto);
#endif     
            } else {
#ifdef DEBUG_REGEXP_GRAPH
        printf("Found simple epsilon trans from %d to %d\n",
               statenr, newto);
#endif     
            for (i = 0;i < state->nbTransTo;i++) {
            tmp = ctxt->states[state->transTo[i]];
            for (j = 0;j < tmp->nbTrans;j++) {
            if (tmp->trans[j].to == statenr) {
#ifdef DEBUG_REGEXP_GRAPH
                printf("Changed transition %d on %d to go to %d\n",
                   j, tmp->no, newto);
#endif     
                tmp->trans[j].to = -1;
                xmlRegStateAddTrans(ctxt, tmp, tmp->trans[j].atom,
                            ctxt->states[newto],
                            tmp->trans[j].counter,
                        tmp->trans[j].count);
            }
            }
        }
        if (state->type == XML_REGEXP_FINAL_STATE)
            ctxt->states[newto]->type = XML_REGEXP_FINAL_STATE;
        /* eliminate the transition completely */
        state->nbTrans = 0;

                state->type = XML_REGEXP_UNREACH_STATE;

        }
            
    }
    }
}
static void
xmlFAEliminateEpsilonTransitions(xmlRegParserCtxtPtr ctxt) {
    int statenr, transnr;
    xmlRegStatePtr state;
    int has_epsilon;

    if (ctxt->states == NULL) return;

    /*
     * Eliminate simple epsilon transition and the associated unreachable
     * states.
     */
    xmlFAEliminateSimpleEpsilonTransitions(ctxt);
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if ((state != NULL) && (state->type == XML_REGEXP_UNREACH_STATE)) {
#ifdef DEBUG_REGEXP_GRAPH
        printf("Removed unreachable state %d\n", statenr);
#endif
        xmlRegFreeState(state);
        ctxt->states[statenr] = NULL;
    }
    }

    has_epsilon = 0;

    /*
     * Build the completed transitions bypassing the epsilons
     * Use a marking algorithm to avoid loops
     * Mark sink states too.
     * Process from the latests states backward to the start when
     * there is long cascading epsilon chains this minimize the
     * recursions and transition compares when adding the new ones
     */
    for (statenr = ctxt->nbStates - 1;statenr >= 0;statenr--) {
    state = ctxt->states[statenr];
    if (state == NULL)
        continue;
    if ((state->nbTrans == 0) &&
        (state->type != XML_REGEXP_FINAL_STATE)) {
        state->type = XML_REGEXP_SINK_STATE;
    }
    for (transnr = 0;transnr < state->nbTrans;transnr++) {
        if ((state->trans[transnr].atom == NULL) &&
        (state->trans[transnr].to >= 0)) {
        if (state->trans[transnr].to == statenr) {
            state->trans[transnr].to = -1;
#ifdef DEBUG_REGEXP_GRAPH
            printf("Removed loopback epsilon trans %d on %d\n",
               transnr, statenr);
#endif
        } else if (state->trans[transnr].count < 0) {
            int newto = state->trans[transnr].to;

#ifdef DEBUG_REGEXP_GRAPH
            printf("Found epsilon trans %d from %d to %d\n",
               transnr, statenr, newto);
#endif
            has_epsilon = 1;
            state->trans[transnr].to = -2;
            state->mark = XML_REGEXP_MARK_START;
            xmlFAReduceEpsilonTransitions(ctxt, statenr,
                      newto, state->trans[transnr].counter);
            state->mark = XML_REGEXP_MARK_NORMAL;
#ifdef DEBUG_REGEXP_GRAPH
        } else {
            printf("Found counted transition %d on %d\n",
               transnr, statenr);
#endif
            }
        }
    }
    }
    /*
     * Eliminate the epsilon transitions
     */
    if (has_epsilon) {
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
        state = ctxt->states[statenr];
        if (state == NULL)
        continue;
        for (transnr = 0;transnr < state->nbTrans;transnr++) {
        xmlRegTransPtr trans = &(state->trans[transnr]);
        if ((trans->atom == NULL) &&
            (trans->count < 0) &&
            (trans->to >= 0)) {
            trans->to = -1;
        }
        }
    }
    }

    /*
     * Use this pass to detect unreachable states too
     */
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if (state != NULL)
        state->reached = XML_REGEXP_MARK_NORMAL;
    }
    state = ctxt->states[0];
    if (state != NULL)
    state->reached = XML_REGEXP_MARK_START;
    while (state != NULL) {
    xmlRegStatePtr target = NULL;
    state->reached = XML_REGEXP_MARK_VISITED;
    /*
     * Mark all states reachable from the current reachable state
     */
    for (transnr = 0;transnr < state->nbTrans;transnr++) {
        if ((state->trans[transnr].to >= 0) &&
        ((state->trans[transnr].atom != NULL) ||
         (state->trans[transnr].count >= 0))) {
        int newto = state->trans[transnr].to;

        if (ctxt->states[newto] == NULL)
            continue;
        if (ctxt->states[newto]->reached == XML_REGEXP_MARK_NORMAL) {
            ctxt->states[newto]->reached = XML_REGEXP_MARK_START;
            target = ctxt->states[newto];
        }
        }
    }

    /*
     * find the next accessible state not explored
     */
    if (target == NULL) {
        for (statenr = 1;statenr < ctxt->nbStates;statenr++) {
        state = ctxt->states[statenr];
        if ((state != NULL) && (state->reached ==
            XML_REGEXP_MARK_START)) {
            target = state;
            break;
        }
        }
    }
    state = target;
    }
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if ((state != NULL) && (state->reached == XML_REGEXP_MARK_NORMAL)) {
#ifdef DEBUG_REGEXP_GRAPH
        printf("Removed unreachable state %d\n", statenr);
#endif
        xmlRegFreeState(state);
        ctxt->states[statenr] = NULL;
    }
    }

}

static int
xmlFACompareRanges(xmlRegRangePtr range1, xmlRegRangePtr range2) {
    int ret = 0;

    if ((range1->type == XML_REGEXP_RANGES) ||
        (range2->type == XML_REGEXP_RANGES) ||
        (range2->type == XML_REGEXP_SUBREG) ||
        (range1->type == XML_REGEXP_SUBREG) ||
        (range1->type == XML_REGEXP_STRING) ||
        (range2->type == XML_REGEXP_STRING))
    return(-1);

    /* put them in order */
    if (range1->type > range2->type) {
        xmlRegRangePtr tmp;

    tmp = range1;
    range1 = range2;
    range2 = tmp;
    }
    if ((range1->type == XML_REGEXP_ANYCHAR) ||
        (range2->type == XML_REGEXP_ANYCHAR)) {
    ret = 1;
    } else if ((range1->type == XML_REGEXP_EPSILON) ||
               (range2->type == XML_REGEXP_EPSILON)) {
    return(0);
    } else if (range1->type == range2->type) {
        if (range1->type != XML_REGEXP_CHARVAL)
            ret = 1;
        else if ((range1->end < range2->start) ||
             (range2->end < range1->start))
        ret = 0;
    else
        ret = 1;
    } else if (range1->type == XML_REGEXP_CHARVAL) {
        int codepoint;
    int neg = 0;

    /*
     * just check all codepoints in the range for acceptance,
     * this is usually way cheaper since done only once at
     * compilation than testing over and over at runtime or 
     * pushing too many states when evaluating.
     */
    if (((range1->neg == 0) && (range2->neg != 0)) ||
        ((range1->neg != 0) && (range2->neg == 0)))
        neg = 1;

    for (codepoint = range1->start;codepoint <= range1->end ;codepoint++) {
        ret = xmlRegCheckCharacterRange(range2->type, codepoint,
                        0, range2->start, range2->end,
                        range2->blockName);
        if (ret < 0)
            return(-1);
        if (((neg == 1) && (ret == 0)) ||
            ((neg == 0) && (ret == 1)))
        return(1);
    }
    return(0);
    } else if ((range1->type == XML_REGEXP_BLOCK_NAME) ||
               (range2->type == XML_REGEXP_BLOCK_NAME)) {
    if (range1->type == range2->type) {
        ret = xmlStrEqual(range1->blockName, range2->blockName);
    } else {
        /*
         * comparing a block range with anything else is way
         * too costly, and maintining the table is like too much
         * memory too, so let's force the automata to save state
         * here.
         */
        return(1);
    }
    } else if ((range1->type < XML_REGEXP_LETTER) ||
               (range2->type < XML_REGEXP_LETTER)) {
    if ((range1->type == XML_REGEXP_ANYSPACE) &&
        (range2->type == XML_REGEXP_NOTSPACE))
        ret = 0;
    else if ((range1->type == XML_REGEXP_INITNAME) &&
             (range2->type == XML_REGEXP_NOTINITNAME))
        ret = 0;
    else if ((range1->type == XML_REGEXP_NAMECHAR) &&
             (range2->type == XML_REGEXP_NOTNAMECHAR))
        ret = 0;
    else if ((range1->type == XML_REGEXP_DECIMAL) &&
             (range2->type == XML_REGEXP_NOTDECIMAL))
        ret = 0;
    else if ((range1->type == XML_REGEXP_REALCHAR) &&
             (range2->type == XML_REGEXP_NOTREALCHAR))
        ret = 0;
    else {
        /* same thing to limit complexity */
        return(1);
    }
    } else {
        ret = 0;
        /* range1->type < range2->type here */
        switch (range1->type) {
        case XML_REGEXP_LETTER:
             /* all disjoint except in the subgroups */
             if ((range2->type == XML_REGEXP_LETTER_UPPERCASE) ||
             (range2->type == XML_REGEXP_LETTER_LOWERCASE) ||
             (range2->type == XML_REGEXP_LETTER_TITLECASE) ||
             (range2->type == XML_REGEXP_LETTER_MODIFIER) ||
             (range2->type == XML_REGEXP_LETTER_OTHERS))
             ret = 1;
         break;
        case XML_REGEXP_MARK:
             if ((range2->type == XML_REGEXP_MARK_NONSPACING) ||
             (range2->type == XML_REGEXP_MARK_SPACECOMBINING) ||
             (range2->type == XML_REGEXP_MARK_ENCLOSING))
             ret = 1;
         break;
        case XML_REGEXP_NUMBER:
             if ((range2->type == XML_REGEXP_NUMBER_DECIMAL) ||
             (range2->type == XML_REGEXP_NUMBER_LETTER) ||
             (range2->type == XML_REGEXP_NUMBER_OTHERS))
             ret = 1;
         break;
        case XML_REGEXP_PUNCT:
             if ((range2->type == XML_REGEXP_PUNCT_CONNECTOR) ||
             (range2->type == XML_REGEXP_PUNCT_DASH) ||
             (range2->type == XML_REGEXP_PUNCT_OPEN) ||
             (range2->type == XML_REGEXP_PUNCT_CLOSE) ||
             (range2->type == XML_REGEXP_PUNCT_INITQUOTE) ||
             (range2->type == XML_REGEXP_PUNCT_FINQUOTE) ||
             (range2->type == XML_REGEXP_PUNCT_OTHERS))
             ret = 1;
         break;
        case XML_REGEXP_SEPAR:
             if ((range2->type == XML_REGEXP_SEPAR_SPACE) ||
             (range2->type == XML_REGEXP_SEPAR_LINE) ||
             (range2->type == XML_REGEXP_SEPAR_PARA))
             ret = 1;
         break;
        case XML_REGEXP_SYMBOL:
             if ((range2->type == XML_REGEXP_SYMBOL_MATH) ||
             (range2->type == XML_REGEXP_SYMBOL_CURRENCY) ||
             (range2->type == XML_REGEXP_SYMBOL_MODIFIER) ||
             (range2->type == XML_REGEXP_SYMBOL_OTHERS))
             ret = 1;
         break;
        case XML_REGEXP_OTHER:
             if ((range2->type == XML_REGEXP_OTHER_CONTROL) ||
             (range2->type == XML_REGEXP_OTHER_FORMAT) ||
             (range2->type == XML_REGEXP_OTHER_PRIVATE))
             ret = 1;
         break;
            default:
             if ((range2->type >= XML_REGEXP_LETTER) &&
             (range2->type < XML_REGEXP_BLOCK_NAME))
             ret = 0;
         else {
             /* safety net ! */
             return(1);
         }
    }
    }
    if (((range1->neg == 0) && (range2->neg != 0)) ||
        ((range1->neg != 0) && (range2->neg == 0)))
    ret = !ret;
    return(ret);
}

static int
xmlFACompareAtomTypes(xmlRegAtomType type1, xmlRegAtomType type2) {
    if ((type1 == XML_REGEXP_EPSILON) ||
        (type1 == XML_REGEXP_CHARVAL) ||
    (type1 == XML_REGEXP_RANGES) ||
    (type1 == XML_REGEXP_SUBREG) ||
    (type1 == XML_REGEXP_STRING) ||
    (type1 == XML_REGEXP_ANYCHAR))
    return(1);
    if ((type2 == XML_REGEXP_EPSILON) ||
        (type2 == XML_REGEXP_CHARVAL) ||
    (type2 == XML_REGEXP_RANGES) ||
    (type2 == XML_REGEXP_SUBREG) ||
    (type2 == XML_REGEXP_STRING) ||
    (type2 == XML_REGEXP_ANYCHAR))
    return(1);

    if (type1 == type2) return(1);

    /* simplify subsequent compares by making sure type1 < type2 */
    if (type1 > type2) {
        xmlRegAtomType tmp = type1;
    type1 = type2;
    type2 = tmp;
    }
    switch (type1) {
        case XML_REGEXP_ANYSPACE: /* \s */
        /* can't be a letter, number, mark, pontuation, symbol */
        if ((type2 == XML_REGEXP_NOTSPACE) ||
        ((type2 >= XML_REGEXP_LETTER) &&
         (type2 <= XML_REGEXP_LETTER_OTHERS)) ||
            ((type2 >= XML_REGEXP_NUMBER) &&
         (type2 <= XML_REGEXP_NUMBER_OTHERS)) ||
            ((type2 >= XML_REGEXP_MARK) &&
         (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
            ((type2 >= XML_REGEXP_PUNCT) &&
         (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
            ((type2 >= XML_REGEXP_SYMBOL) &&
         (type2 <= XML_REGEXP_SYMBOL_OTHERS))
            ) return(0);
        break;
        case XML_REGEXP_NOTSPACE: /* \S */
        break;
        case XML_REGEXP_INITNAME: /* \l */
        /* can't be a number, mark, separator, pontuation, symbol or other */
        if ((type2 == XML_REGEXP_NOTINITNAME) ||
            ((type2 >= XML_REGEXP_NUMBER) &&
         (type2 <= XML_REGEXP_NUMBER_OTHERS)) ||
            ((type2 >= XML_REGEXP_MARK) &&
         (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
            ((type2 >= XML_REGEXP_SEPAR) &&
         (type2 <= XML_REGEXP_SEPAR_PARA)) ||
            ((type2 >= XML_REGEXP_PUNCT) &&
         (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
            ((type2 >= XML_REGEXP_SYMBOL) &&
         (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
            ((type2 >= XML_REGEXP_OTHER) &&
         (type2 <= XML_REGEXP_OTHER_NA))
        ) return(0);
        break;
        case XML_REGEXP_NOTINITNAME: /* \L */
        break;
        case XML_REGEXP_NAMECHAR: /* \c */
        /* can't be a mark, separator, pontuation, symbol or other */
        if ((type2 == XML_REGEXP_NOTNAMECHAR) ||
            ((type2 >= XML_REGEXP_MARK) &&
         (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
            ((type2 >= XML_REGEXP_PUNCT) &&
         (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
            ((type2 >= XML_REGEXP_SEPAR) &&
         (type2 <= XML_REGEXP_SEPAR_PARA)) ||
            ((type2 >= XML_REGEXP_SYMBOL) &&
         (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
            ((type2 >= XML_REGEXP_OTHER) &&
         (type2 <= XML_REGEXP_OTHER_NA))
        ) return(0);
        break;
        case XML_REGEXP_NOTNAMECHAR: /* \C */
        break;
        case XML_REGEXP_DECIMAL: /* \d */
        /* can't be a letter, mark, separator, pontuation, symbol or other */
        if ((type2 == XML_REGEXP_NOTDECIMAL) ||
            (type2 == XML_REGEXP_REALCHAR) ||
        ((type2 >= XML_REGEXP_LETTER) &&
         (type2 <= XML_REGEXP_LETTER_OTHERS)) ||
            ((type2 >= XML_REGEXP_MARK) &&
         (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
            ((type2 >= XML_REGEXP_PUNCT) &&
         (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
            ((type2 >= XML_REGEXP_SEPAR) &&
         (type2 <= XML_REGEXP_SEPAR_PARA)) ||
            ((type2 >= XML_REGEXP_SYMBOL) &&
         (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
            ((type2 >= XML_REGEXP_OTHER) &&
         (type2 <= XML_REGEXP_OTHER_NA))
        )return(0);
        break;
        case XML_REGEXP_NOTDECIMAL: /* \D */
        break;
        case XML_REGEXP_REALCHAR: /* \w */
        /* can't be a mark, separator, pontuation, symbol or other */
        if ((type2 == XML_REGEXP_NOTDECIMAL) ||
            ((type2 >= XML_REGEXP_MARK) &&
         (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
            ((type2 >= XML_REGEXP_PUNCT) &&
         (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
            ((type2 >= XML_REGEXP_SEPAR) &&
         (type2 <= XML_REGEXP_SEPAR_PARA)) ||
            ((type2 >= XML_REGEXP_SYMBOL) &&
         (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
            ((type2 >= XML_REGEXP_OTHER) &&
         (type2 <= XML_REGEXP_OTHER_NA))
        )return(0);
        break;
        case XML_REGEXP_NOTREALCHAR: /* \W */
        break;
    /*
     * at that point we know both type 1 and type2 are from
     * character categories are ordered and are different,
     * it becomes simple because this is a partition
     */
        case XML_REGEXP_LETTER:
        if (type2 <= XML_REGEXP_LETTER_OTHERS)
            return(1);
        return(0);
        case XML_REGEXP_LETTER_UPPERCASE:
        case XML_REGEXP_LETTER_LOWERCASE:
        case XML_REGEXP_LETTER_TITLECASE:
        case XML_REGEXP_LETTER_MODIFIER:
        case XML_REGEXP_LETTER_OTHERS:
        return(0);
        case XML_REGEXP_MARK:
        if (type2 <= XML_REGEXP_MARK_ENCLOSING)
            return(1);
        return(0);
        case XML_REGEXP_MARK_NONSPACING:
        case XML_REGEXP_MARK_SPACECOMBINING:
        case XML_REGEXP_MARK_ENCLOSING:
        return(0);
        case XML_REGEXP_NUMBER:
        if (type2 <= XML_REGEXP_NUMBER_OTHERS)
            return(1);
        return(0);
        case XML_REGEXP_NUMBER_DECIMAL:
        case XML_REGEXP_NUMBER_LETTER:
        case XML_REGEXP_NUMBER_OTHERS:
        return(0);
        case XML_REGEXP_PUNCT:
        if (type2 <= XML_REGEXP_PUNCT_OTHERS)
            return(1);
        return(0);
        case XML_REGEXP_PUNCT_CONNECTOR:
        case XML_REGEXP_PUNCT_DASH:
        case XML_REGEXP_PUNCT_OPEN:
        case XML_REGEXP_PUNCT_CLOSE:
        case XML_REGEXP_PUNCT_INITQUOTE:
        case XML_REGEXP_PUNCT_FINQUOTE:
        case XML_REGEXP_PUNCT_OTHERS:
        return(0);
        case XML_REGEXP_SEPAR:
        if (type2 <= XML_REGEXP_SEPAR_PARA)
            return(1);
        return(0);
        case XML_REGEXP_SEPAR_SPACE:
        case XML_REGEXP_SEPAR_LINE:
        case XML_REGEXP_SEPAR_PARA:
        return(0);
        case XML_REGEXP_SYMBOL:
        if (type2 <= XML_REGEXP_SYMBOL_OTHERS)
            return(1);
        return(0);
        case XML_REGEXP_SYMBOL_MATH:
        case XML_REGEXP_SYMBOL_CURRENCY:
        case XML_REGEXP_SYMBOL_MODIFIER:
        case XML_REGEXP_SYMBOL_OTHERS:
        return(0);
        case XML_REGEXP_OTHER:
        if (type2 <= XML_REGEXP_OTHER_NA)
            return(1);
        return(0);
        case XML_REGEXP_OTHER_CONTROL:
        case XML_REGEXP_OTHER_FORMAT:
        case XML_REGEXP_OTHER_PRIVATE:
        case XML_REGEXP_OTHER_NA:
        return(0);
    default:
        break;
    }
    return(1);
}

static int
xmlFAEqualAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2, int deep) {
    int ret = 0;

    if (atom1 == atom2)
    return(1);
    if ((atom1 == NULL) || (atom2 == NULL))
    return(0);

    if (atom1->type != atom2->type)
        return(0);
    switch (atom1->type) {
        case XML_REGEXP_EPSILON:
        ret = 0;
        break;
        case XML_REGEXP_STRING:
            if (!deep)
                ret = (atom1->valuep == atom2->valuep);
            else
                ret = xmlStrEqual((xmlChar *)atom1->valuep,
                                  (xmlChar *)atom2->valuep);
        break;
        case XML_REGEXP_CHARVAL:
        ret = (atom1->codepoint == atom2->codepoint);
        break;
    case XML_REGEXP_RANGES:
        /* too hard to do in the general case */
        ret = 0;
    default:
        break;
    }
    return(ret);
}

static int
xmlFACompareAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2, int deep) {
    int ret = 1;

    if (atom1 == atom2)
    return(1);
    if ((atom1 == NULL) || (atom2 == NULL))
    return(0);

    if ((atom1->type == XML_REGEXP_ANYCHAR) ||
        (atom2->type == XML_REGEXP_ANYCHAR))
    return(1);

    if (atom1->type > atom2->type) {
    xmlRegAtomPtr tmp;
    tmp = atom1;
    atom1 = atom2;
    atom2 = tmp;
    }
    if (atom1->type != atom2->type) {
        ret = xmlFACompareAtomTypes(atom1->type, atom2->type);
    /* if they can't intersect at the type level break now */
    if (ret == 0)
        return(0);
    }
    switch (atom1->type) {
        case XML_REGEXP_STRING:
            if (!deep)
                ret = (atom1->valuep != atom2->valuep);
            else
                ret = xmlRegStrEqualWildcard((xmlChar *)atom1->valuep,
                                             (xmlChar *)atom2->valuep);
        break;
        case XML_REGEXP_EPSILON:
        goto not_determinist;
        case XML_REGEXP_CHARVAL:
        if (atom2->type == XML_REGEXP_CHARVAL) {
        ret = (atom1->codepoint == atom2->codepoint);
        } else {
            ret = xmlRegCheckCharacter(atom2, atom1->codepoint);
        if (ret < 0)
            ret = 1;
        }
        break;
        case XML_REGEXP_RANGES:
        if (atom2->type == XML_REGEXP_RANGES) {
            int i, j, res;
        xmlRegRangePtr r1, r2;

        /*
         * need to check that none of the ranges eventually matches
         */
        for (i = 0;i < atom1->nbRanges;i++) {
            for (j = 0;j < atom2->nbRanges;j++) {
            r1 = atom1->ranges[i];
            r2 = atom2->ranges[j];
            res = xmlFACompareRanges(r1, r2);
            if (res == 1) {
                ret = 1;
                goto done;
            }
            }
        }
        ret = 0;
        }
        break;
    default:
        goto not_determinist;
    }
done:
    if (atom1->neg != atom2->neg) {
        ret = !ret;
    }
    if (ret == 0)
        return(0);
not_determinist:
    return(1);
}

static int
xmlFARecurseDeterminism(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state,
                     int to, xmlRegAtomPtr atom) {
    int ret = 1;
    int res;
    int transnr, nbTrans;
    xmlRegTransPtr t1;
    int deep = 1;

    if (state == NULL)
    return(ret);

    if (ctxt->flags & AM_AUTOMATA_RNG)
        deep = 0;

    /*
     * don't recurse on transitions potentially added in the course of
     * the elimination.
     */
    nbTrans = state->nbTrans;
    for (transnr = 0;transnr < nbTrans;transnr++) {
    t1 = &(state->trans[transnr]);
    /*
     * check transitions conflicting with the one looked at
     */
    if (t1->atom == NULL) {
        if (t1->to < 0)
        continue;
        res = xmlFARecurseDeterminism(ctxt, ctxt->states[t1->to],
                                   to, atom);
        if (res == 0) {
            ret = 0;
        /* t1->nd = 1; */
        }
        continue;
    }
    if (t1->to != to)
        continue;
    if (xmlFACompareAtoms(t1->atom, atom, deep)) {
        ret = 0;
        /* mark the transition as non-deterministic */
        t1->nd = 1;
    }
    }
    return(ret);
}

static int
xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt) {
    int statenr, transnr;
    xmlRegStatePtr state;
    xmlRegTransPtr t1, t2, last;
    int i;
    int ret = 1;
    int deep = 1;

#ifdef DEBUG_REGEXP_GRAPH
    printf("xmlFAComputesDeterminism\n");
    xmlRegPrintCtxt(stdout, ctxt);
#endif
    if (ctxt->determinist != -1)
    return(ctxt->determinist);

    if (ctxt->flags & AM_AUTOMATA_RNG)
        deep = 0;

    /*
     * First cleanup the automata removing cancelled transitions
     */
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if (state == NULL)
        continue;
    if (state->nbTrans < 2)
        continue;
    for (transnr = 0;transnr < state->nbTrans;transnr++) {
        t1 = &(state->trans[transnr]);
        /*
         * Determinism checks in case of counted or all transitions
         * will have to be handled separately
         */
        if (t1->atom == NULL) {
        /* t1->nd = 1; */
        continue;
        }
        if (t1->to == -1) /* eliminated */
        continue;
        for (i = 0;i < transnr;i++) {
        t2 = &(state->trans[i]);
        if (t2->to == -1) /* eliminated */
            continue;
        if (t2->atom != NULL) {
            if (t1->to == t2->to) {
                        /*
                         * Here we use deep because we want to keep the
                         * transitions which indicate a conflict
                         */
            if (xmlFAEqualAtoms(t1->atom, t2->atom, deep) &&
                            (t1->counter == t2->counter) &&
                            (t1->count == t2->count))
                t2->to = -1; /* eliminated */
            }
        }
        }
    }
    }

    /*
     * Check for all states that there aren't 2 transitions
     * with the same atom and a different target.
     */
    for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
    state = ctxt->states[statenr];
    if (state == NULL)
        continue;
    if (state->nbTrans < 2)
        continue;
    last = NULL;
    for (transnr = 0;transnr < state->nbTrans;transnr++) {
        t1 = &(state->trans[transnr]);
        /*
         * Determinism checks in case of counted or all transitions
         * will have to be handled separately
         */
        if (t1->atom == NULL) {
        continue;
        }
        if (t1->to == -1) /* eliminated */
        continue;
        for (i = 0;i < transnr;i++) {
        t2 = &(state->trans[i]);
        if (t2->to == -1) /* eliminated */
            continue;
        if (t2->atom != NULL) {
                    /*
                     * But here we don't use deep because we want to
                     * find transitions which indicate a conflict
                     */
            if (xmlFACompareAtoms(t1->atom, t2->atom, 1)) {
            ret = 0;
            /* mark the transitions as non-deterministic ones */
            t1->nd = 1;
            t2->nd = 1;
            last = t1;
            }
        } else if (t1->to != -1) {
            /*
             * do the closure in case of remaining specific
             * epsilon transitions like choices or all
             */
            ret = xmlFARecurseDeterminism(ctxt, ctxt->states[t1->to],
                           t2->to, t2->atom);
            /* don't shortcut the computation so all non deterministic
               transition get marked down
            if (ret == 0)
            return(0);
             */
            if (ret == 0) {
            t1->nd = 1;
            /* t2->nd = 1; */
            last = t1;
            }
        }
        }
        /* don't shortcut the computation so all non deterministic
           transition get marked down
        if (ret == 0)
        break; */
    }

    /*
     * mark specifically the last non-deterministic transition
     * from a state since there is no need to set-up rollback
     * from it
     */
    if (last != NULL) {
        last->nd = 2;
    }

    /* don't shortcut the computation so all non deterministic
       transition get marked down
    if (ret == 0)
        break; */
    }

    ctxt->determinist = ret;
    return(ret);
}

/************************************************************************
 *                                  *
 *  Routines to check input against transition atoms        *
 *                                  *
 ************************************************************************/

static int
xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint, int neg,
                      int start, int end, const xmlChar *blockName) {
    int ret = 0;

    switch (type) {
        case XML_REGEXP_STRING:
        case XML_REGEXP_SUBREG:
        case XML_REGEXP_RANGES:
        case XML_REGEXP_EPSILON:
        return(-1);
        case XML_REGEXP_ANYCHAR:
        ret = ((codepoint != '\n') && (codepoint != '\r'));
        break;
        case XML_REGEXP_CHARVAL:
        ret = ((codepoint >= start) && (codepoint <= end));
        break;
        case XML_REGEXP_NOTSPACE:
        neg = !neg;
        case XML_REGEXP_ANYSPACE:
        ret = ((codepoint == '\n') || (codepoint == '\r') ||
           (codepoint == '\t') || (codepoint == ' '));
        break;
        case XML_REGEXP_NOTINITNAME:
        neg = !neg;
        case XML_REGEXP_INITNAME:
        ret = (IS_LETTER(codepoint) || 
           (codepoint == '_') || (codepoint == ':'));
        break;
        case XML_REGEXP_NOTNAMECHAR:
        neg = !neg;
        case XML_REGEXP_NAMECHAR:
        ret = (IS_LETTER(codepoint) || IS_DIGIT(codepoint) ||
           (codepoint == '.') || (codepoint == '-') ||
           (codepoint == '_') || (codepoint == ':') ||
           IS_COMBINING(codepoint) || IS_EXTENDER(codepoint));
        break;
        case XML_REGEXP_NOTDECIMAL:
        neg = !neg;
        case XML_REGEXP_DECIMAL:
        ret = xmlUCSIsCatNd(codepoint);
        break;
        case XML_REGEXP_REALCHAR:
        neg = !neg;
        case XML_REGEXP_NOTREALCHAR:
        ret = xmlUCSIsCatP(codepoint);
        if (ret == 0)
        ret = xmlUCSIsCatZ(codepoint);
        if (ret == 0)
        ret = xmlUCSIsCatC(codepoint);
        break;
        case XML_REGEXP_LETTER:
        ret = xmlUCSIsCatL(codepoint);
        break;
        case XML_REGEXP_LETTER_UPPERCASE:
        ret = xmlUCSIsCatLu(codepoint);
        break;
        case XML_REGEXP_LETTER_LOWERCASE:
        ret = xmlUCSIsCatLl(codepoint);
        break;
        case XML_REGEXP_LETTER_TITLECASE:
        ret = xmlUCSIsCatLt(codepoint);
        break;
        case XML_REGEXP_LETTER_MODIFIER:
        ret = xmlUCSIsCatLm(codepoint);
        break;
        case XML_REGEXP_LETTER_OTHERS:
        ret = xmlUCSIsCatLo(codepoint);
        break;
        case XML_REGEXP_MARK:
        ret = xmlUCSIsCatM(codepoint);
        break;
        case XML_REGEXP_MARK_NONSPACING:
        ret = xmlUCSIsCatMn(codepoint);
        break;
        case XML_REGEXP_MARK_SPACECOMBINING:
        ret = xmlUCSIsCatMc(codepoint);
        break;
        case XML_REGEXP_MARK_ENCLOSING:
        ret = xmlUCSIsCatMe(codepoint);
        break;
        case XML_REGEXP_NUMBER:
        ret = xmlUCSIsCatN(codepoint);
        break;
        case XML_REGEXP_NUMBER_DECIMAL:
        ret = xmlUCSIsCatNd(codepoint);
        break;
        case XML_REGEXP_NUMBER_LETTER:
        ret = xmlUCSIsCatNl(codepoint);
        break;
        case XML_REGEXP_NUMBER_OTHERS:
        ret = xmlUCSIsCatNo(codepoint);
        break;
        case XML_REGEXP_PUNCT:
        ret = xmlUCSIsCatP(codepoint);
        break;
        case XML_REGEXP_PUNCT_CONNECTOR:
        ret = xmlUCSIsCatPc(codepoint);
        break;
        case XML_REGEXP_PUNCT_DASH:
        ret = xmlUCSIsCatPd(codepoint);
        break;
        case XML_REGEXP_PUNCT_OPEN:
        ret = xmlUCSIsCatPs(codepoint);
        break;
        case XML_REGEXP_PUNCT_CLOSE:
        ret = xmlUCSIsCatPe(codepoint);
        break;
        case XML_REGEXP_PUNCT_INITQUOTE:
        ret = xmlUCSIsCatPi(codepoint);
        break;
        case XML_REGEXP_PUNCT_FINQUOTE:
        ret = xmlUCSIsCatPf(codepoint);
        break;
        case XML_REGEXP_PUNCT_OTHERS:
        ret = xmlUCSIsCatPo(codepoint);
        break;
        case XML_REGEXP_SEPAR:
        ret = xmlUCSIsCatZ(codepoint);
        break;
        case XML_REGEXP_SEPAR_SPACE:
        ret = xmlUCSIsCatZs(codepoint);
        break;
        case XML_REGEXP_SEPAR_LINE:
        ret = xmlUCSIsCatZl(codepoint);
        break;
        case XML_REGEXP_SEPAR_PARA:
        ret = xmlUCSIsCatZp(codepoint);
        break;
        case XML_REGEXP_SYMBOL:
        ret = xmlUCSIsCatS(codepoint);
        break;
        case XML_REGEXP_SYMBOL_MATH:
        ret = xmlUCSIsCatSm(codepoint);
        break;
        case XML_REGEXP_SYMBOL_CURRENCY:
        ret = xmlUCSIsCatSc(codepoint);
        break;
        case XML_REGEXP_SYMBOL_MODIFIER:
        ret = xmlUCSIsCatSk(codepoint);
        break;
        case XML_REGEXP_SYMBOL_OTHERS:
        ret = xmlUCSIsCatSo(codepoint);
        break;
        case XML_REGEXP_OTHER:
        ret = xmlUCSIsCatC(codepoint);
        break;
        case XML_REGEXP_OTHER_CONTROL:
        ret = xmlUCSIsCatCc(codepoint);
        break;
        case XML_REGEXP_OTHER_FORMAT:
        ret = xmlUCSIsCatCf(codepoint);
        break;
        case XML_REGEXP_OTHER_PRIVATE:
        ret = xmlUCSIsCatCo(codepoint);
        break;
        case XML_REGEXP_OTHER_NA:
        /* ret = xmlUCSIsCatCn(codepoint); */
        /* Seems it doesn't exist anymore in recent Unicode releases */
        ret = 0;
        break;
        case XML_REGEXP_BLOCK_NAME:
        ret = xmlUCSIsBlock(codepoint, (const char *) blockName);
        break;
    }
    if (neg)
    return(!ret);
    return(ret);
}

static int
xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint) {
    int i, ret = 0;
    xmlRegRangePtr range;

    if ((atom == NULL) || (!IS_CHAR(codepoint)))
    return(-1);

    switch (atom->type) {
        case XML_REGEXP_SUBREG:
        case XML_REGEXP_EPSILON:
        return(-1);
        case XML_REGEXP_CHARVAL:
            return(codepoint == atom->codepoint);
        case XML_REGEXP_RANGES: {
        int accept = 0;

        for (i = 0;i < atom->nbRanges;i++) {
        range = atom->ranges[i];
        if (range->neg == 2) {
            ret = xmlRegCheckCharacterRange(range->type, codepoint,
                        0, range->start, range->end,
                        range->blockName);
            if (ret != 0)
            return(0); /* excluded char */
        } else if (range->neg) {
            ret = xmlRegCheckCharacterRange(range->type, codepoint,
                        0, range->start, range->end,
                        range->blockName);
            if (ret == 0)
                accept = 1;
            else
                return(0);
        } else {
            ret = xmlRegCheckCharacterRange(range->type, codepoint,
                        0, range->start, range->end,
                        range->blockName);
            if (ret != 0)
            accept = 1; /* might still be excluded */
        }
        }
        return(accept);
    }
        case XML_REGEXP_STRING:
        printf("TODO: XML_REGEXP_STRING\n");
        return(-1);
        case XML_REGEXP_ANYCHAR:
        case XML_REGEXP_ANYSPACE:
        case XML_REGEXP_NOTSPACE:
        case XML_REGEXP_INITNAME:
        case XML_REGEXP_NOTINITNAME:
        case XML_REGEXP_NAMECHAR:
        case XML_REGEXP_NOTNAMECHAR:
        case XML_REGEXP_DECIMAL:
        case XML_REGEXP_NOTDECIMAL:
        case XML_REGEXP_REALCHAR:
        case XML_REGEXP_NOTREALCHAR:
        case XML_REGEXP_LETTER:
        case XML_REGEXP_LETTER_UPPERCASE:
        case XML_REGEXP_LETTER_LOWERCASE:
        case XML_REGEXP_LETTER_TITLECASE:
        case XML_REGEXP_LETTER_MODIFIER:
        case XML_REGEXP_LETTER_OTHERS:
        case XML_REGEXP_MARK:
        case XML_REGEXP_MARK_NONSPACING:
        case XML_REGEXP_MARK_SPACECOMBINING:
        case XML_REGEXP_MARK_ENCLOSING:
        case XML_REGEXP_NUMBER:
        case XML_REGEXP_NUMBER_DECIMAL:
        case XML_REGEXP_NUMBER_LETTER:
        case XML_REGEXP_NUMBER_OTHERS:
        case XML_REGEXP_PUNCT:
        case XML_REGEXP_PUNCT_CONNECTOR:
        case XML_REGEXP_PUNCT_DASH:
        case XML_REGEXP_PUNCT_OPEN:
        case XML_REGEXP_PUNCT_CLOSE:
        case XML_REGEXP_PUNCT_INITQUOTE:
        case XML_REGEXP_PUNCT_FINQUOTE:
        case XML_REGEXP_PUNCT_OTHERS:
        case XML_REGEXP_SEPAR:
        case XML_REGEXP_SEPAR_SPACE:
        case XML_REGEXP_SEPAR_LINE:
        case XML_REGEXP_SEPAR_PARA:
        case XML_REGEXP_SYMBOL:
        case XML_REGEXP_SYMBOL_MATH:
        case XML_REGEXP_SYMBOL_CURRENCY:
        case XML_REGEXP_SYMBOL_MODIFIER:
        case XML_REGEXP_SYMBOL_OTHERS:
        case XML_REGEXP_OTHER:
        case XML_REGEXP_OTHER_CONTROL:
        case XML_REGEXP_OTHER_FORMAT:
        case XML_REGEXP_OTHER_PRIVATE:
        case XML_REGEXP_OTHER_NA:
    case XML_REGEXP_BLOCK_NAME:
        ret = xmlRegCheckCharacterRange(atom->type, codepoint, 0, 0, 0,
                                    (const xmlChar *)atom->valuep);
        if (atom->neg)
        ret = !ret;
        break;
    }
    return(ret);
}

/************************************************************************
 *                                  *
 *  Saving and restoring state of an execution context      *
 *                                  *
 ************************************************************************/

#ifdef DEBUG_REGEXP_EXEC
static void
xmlFARegDebugExec(xmlRegExecCtxtPtr exec) {
    printf("state: %d:%d:idx %d", exec->state->no, exec->transno, exec->index);
    if (exec->inputStack != NULL) {
    int i;
    printf(": ");
    for (i = 0;(i < 3) && (i < exec->inputStackNr);i++)
        printf("%s ", (const char *)
               exec->inputStack[exec->inputStackNr - (i + 1)].value);
    } else {
    printf(": %s", &(exec->inputString[exec->index]));
    }
    printf("\n");
}
#endif

static void
xmlFARegExecSave(xmlRegExecCtxtPtr exec) {
#ifdef DEBUG_REGEXP_EXEC
    printf("saving ");
    exec->transno++;
    xmlFARegDebugExec(exec);
    exec->transno--;
#endif
#ifdef MAX_PUSH
    if (exec->nbPush > MAX_PUSH) {
        return;
    }
    exec->nbPush++;
#endif

    if (exec->maxRollbacks == 0) {
    exec->maxRollbacks = 4;
    exec->rollbacks = (xmlRegExecRollback *) xmlMalloc(exec->maxRollbacks *
                                     sizeof(xmlRegExecRollback));
    if (exec->rollbacks == NULL) {
        xmlRegexpErrMemory(NULL, "saving regexp");
        exec->maxRollbacks = 0;
        return;
    }
    memset(exec->rollbacks, 0,
           exec->maxRollbacks * sizeof(xmlRegExecRollback));
    } else if (exec->nbRollbacks >= exec->maxRollbacks) {
    xmlRegExecRollback *tmp;
    int len = exec->maxRollbacks;

    exec->maxRollbacks *= 2;
    tmp = (xmlRegExecRollback *) xmlRealloc(exec->rollbacks,
            exec->maxRollbacks * sizeof(xmlRegExecRollback));
    if (tmp == NULL) {
        xmlRegexpErrMemory(NULL, "saving regexp");
        exec->maxRollbacks /= 2;
        return;
    }
    exec->rollbacks = tmp;
    tmp = &exec->rollbacks[len];
    memset(tmp, 0, (exec->maxRollbacks - len) * sizeof(xmlRegExecRollback));
    }
    exec->rollbacks[exec->nbRollbacks].state = exec->state;
    exec->rollbacks[exec->nbRollbacks].index = exec->index;
    exec->rollbacks[exec->nbRollbacks].nextbranch = exec->transno + 1;
    if (exec->comp->nbCounters > 0) {
    if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
        exec->rollbacks[exec->nbRollbacks].counts = (int *)
        xmlMalloc(exec->comp->nbCounters * sizeof(int));
        if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
        xmlRegexpErrMemory(NULL, "saving regexp");
        exec->status = -5;
        return;
        }
    }
    memcpy(exec->rollbacks[exec->nbRollbacks].counts, exec->counts,
           exec->comp->nbCounters * sizeof(int));
    }
    exec->nbRollbacks++;
}

static void
xmlFARegExecRollBack(xmlRegExecCtxtPtr exec) {
    if (exec->nbRollbacks <= 0) {
    exec->status = -1;
#ifdef DEBUG_REGEXP_EXEC
    printf("rollback failed on empty stack\n");
#endif
    return;
    }
    exec->nbRollbacks--;
    exec->state = exec->rollbacks[exec->nbRollbacks].state;
    exec->index = exec->rollbacks[exec->nbRollbacks].index;
    exec->transno = exec->rollbacks[exec->nbRollbacks].nextbranch;
    if (exec->comp->nbCounters > 0) {
    if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
        fprintf(stderr, "exec save: allocation failed");
        exec->status = -6;
        return;
    }
    memcpy(exec->counts, exec->rollbacks[exec->nbRollbacks].counts,
           exec->comp->nbCounters * sizeof(int));
    }

#ifdef DEBUG_REGEXP_EXEC
    printf("restored ");
    xmlFARegDebugExec(exec);
#endif
}

/************************************************************************
 *                                  *
 *  Verifier, running an input against a compiled regexp        *
 *                                  *
 ************************************************************************/

static int
xmlFARegExec(xmlRegexpPtr comp, const xmlChar *content) {
    xmlRegExecCtxt execval;
    xmlRegExecCtxtPtr exec = &execval;
    int ret, codepoint = 0, len, deter;

    exec->inputString = content;
    exec->index = 0;
    exec->nbPush = 0;
    exec->determinist = 1;
    exec->maxRollbacks = 0;
    exec->nbRollbacks = 0;
    exec->rollbacks = NULL;
    exec->status = 0;
    exec->comp = comp;
    exec->state = comp->states[0];
    exec->transno = 0;
    exec->transcount = 0;
    exec->inputStack = NULL;
    exec->inputStackMax = 0;
    if (comp->nbCounters > 0) {
    exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int));
    if (exec->counts == NULL) {
        xmlRegexpErrMemory(NULL, "running regexp");
        return(-1);
    }
        memset(exec->counts, 0, comp->nbCounters * sizeof(int));
    } else
    exec->counts = NULL;
    while ((exec->status == 0) &&
       ((exec->inputString[exec->index] != 0) ||
        ((exec->state != NULL) &&
         (exec->state->type != XML_REGEXP_FINAL_STATE)))) {
    xmlRegTransPtr trans;
    xmlRegAtomPtr atom;

    /*
     * If end of input on non-terminal state, rollback, however we may
     * still have epsilon like transition for counted transitions
     * on counters, in that case don't break too early.  Additionally,
     * if we are working on a range like "AB{0,2}", where B is not present,
     * we don't want to break.
     */
    len = 1;
    if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL)) {
        /*
         * if there is a transition, we must check if
         *  atom allows minOccurs of 0
         */
        if (exec->transno < exec->state->nbTrans) {
            trans = &exec->state->trans[exec->transno];
        if (trans->to >=0) {
            atom = trans->atom;
            if (!((atom->min == 0) && (atom->max > 0)))
                goto rollback;
        }
        } else
            goto rollback;
    }

    exec->transcount = 0;
    for (;exec->transno < exec->state->nbTrans;exec->transno++) {
        trans = &exec->state->trans[exec->transno];
        if (trans->to < 0)
        continue;
        atom = trans->atom;
        ret = 0;
        deter = 1;
        if (trans->count >= 0) {
        int count;
        xmlRegCounterPtr counter;

        if (exec->counts == NULL) {
            exec->status = -1;
            goto error;
        }
        /*
         * A counted transition.
         */

        count = exec->counts[trans->count];
        counter = &exec->comp->counters[trans->count];
#ifdef DEBUG_REGEXP_EXEC
        printf("testing count %d: val %d, min %d, max %d\n",
               trans->count, count, counter->min,  counter->max);
#endif
        ret = ((count >= counter->min) && (count <= counter->max));
        if ((ret) && (counter->min != counter->max))
            deter = 0;
        } else if (atom == NULL) {
        fprintf(stderr, "epsilon transition left at runtime\n");
        exec->status = -2;
        break;
        } else if (exec->inputString[exec->index] != 0) {
                codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len);
        ret = xmlRegCheckCharacter(atom, codepoint);
        if ((ret == 1) && (atom->min >= 0) && (atom->max > 0)) {
            xmlRegStatePtr to = comp->states[trans->to];

            /*
             * this is a multiple input sequence
             * If there is a counter associated increment it now.
             * before potentially saving and rollback
             * do not increment if the counter is already over the
             * maximum limit in which case get to next transition
             */
            if (trans->counter >= 0) {
            xmlRegCounterPtr counter;

            if ((exec->counts == NULL) ||
                (exec->comp == NULL) ||
                (exec->comp->counters == NULL)) {
                exec->status = -1;
                goto error;
            }
            counter = &exec->comp->counters[trans->counter];
            if (exec->counts[trans->counter] >= counter->max)
                continue; /* for loop on transitions */

#ifdef DEBUG_REGEXP_EXEC
            printf("Increasing count %d\n", trans->counter);
#endif
            exec->counts[trans->counter]++;
            }
            if (exec->state->nbTrans > exec->transno + 1) {
            xmlFARegExecSave(exec);
            }
            exec->transcount = 1;
            do {
            /*
             * Try to progress as much as possible on the input
             */
            if (exec->transcount == atom->max) {
                break;
            }
            exec->index += len;
            /*
             * End of input: stop here
             */
            if (exec->inputString[exec->index] == 0) {
                exec->index -= len;
                break;
            }
            if (exec->transcount >= atom->min) {
                int transno = exec->transno;
                xmlRegStatePtr state = exec->state;

                /*
                 * The transition is acceptable save it
                 */
                exec->transno = -1; /* trick */
                exec->state = to;
                xmlFARegExecSave(exec);
                exec->transno = transno;
                exec->state = state;
            }
            codepoint = CUR_SCHAR(&(exec->inputString[exec->index]),
                              len);
            ret = xmlRegCheckCharacter(atom, codepoint);
            exec->transcount++;
            } while (ret == 1);
            if (exec->transcount < atom->min)
            ret = 0;

            /*
             * If the last check failed but one transition was found
             * possible, rollback
             */
            if (ret < 0)
            ret = 0;
            if (ret == 0) {
            goto rollback;
            }
            if (trans->counter >= 0) {
            if (exec->counts == NULL) {
                exec->status = -1;
                goto error;
            }
#ifdef DEBUG_REGEXP_EXEC
            printf("Decreasing count %d\n", trans->counter);
#endif
            exec->counts[trans->counter]--;
            }
        } else if ((ret == 0) && (atom->min == 0) && (atom->max > 0)) {
            /*
             * we don't match on the codepoint, but minOccurs of 0
             * says that's ok.  Setting len to 0 inhibits stepping
             * over the codepoint.
             */
            exec->transcount = 1;
            len = 0;
            ret = 1;
        }
        } else if ((atom->min == 0) && (atom->max > 0)) {
            /* another spot to match when minOccurs is 0 */
        exec->transcount = 1;
        len = 0;
        ret = 1;
        }
        if (ret == 1) {
        if ((trans->nd == 1) ||
            ((trans->count >= 0) && (deter == 0) &&
             (exec->state->nbTrans > exec->transno + 1))) {
#ifdef DEBUG_REGEXP_EXEC
            if (trans->nd == 1)
                printf("Saving on nd transition atom %d for %c at %d\n",
                   trans->atom->no, codepoint, exec->index);
            else
                printf("Saving on counted transition count %d for %c at %d\n",
                   trans->count, codepoint, exec->index);
#endif
            xmlFARegExecSave(exec);
        }
        if (trans->counter >= 0) {
            xmlRegCounterPtr counter;

                    /* make sure we don't go over the counter maximum value */
            if ((exec->counts == NULL) ||
            (exec->comp == NULL) ||
            (exec->comp->counters == NULL)) {
            exec->status = -1;
            goto error;
            }
            counter = &exec->comp->counters[trans->counter];
            if (exec->counts[trans->counter] >= counter->max)
            continue; /* for loop on transitions */
#ifdef DEBUG_REGEXP_EXEC
            printf("Increasing count %d\n", trans->counter);
#endif
            exec->counts[trans->counter]++;
        }
        if ((trans->count >= 0) &&
            (trans->count < REGEXP_ALL_COUNTER)) {
            if (exec->counts == NULL) {
                exec->status = -1;
            goto error;
            }
#ifdef DEBUG_REGEXP_EXEC
            printf("resetting count %d on transition\n",
                   trans->count);
#endif
            exec->counts[trans->count] = 0;
        }
#ifdef DEBUG_REGEXP_EXEC
        printf("entering state %d\n", trans->to);
#endif
        exec->state = comp->states[trans->to];
        exec->transno = 0;
        if (trans->atom != NULL) {
            exec->index += len;
        }
        goto progress;
        } else if (ret < 0) {
        exec->status = -4;
        break;
        }
    }
    if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
rollback:
        /*
         * Failed to find a way out
         */
        exec->determinist = 0;
#ifdef DEBUG_REGEXP_EXEC
        printf("rollback from state %d on %d:%c\n", exec->state->no,
               codepoint,codepoint);
#endif
        xmlFARegExecRollBack(exec);
    }
progress:
    continue;
    }
error:
    if (exec->rollbacks != NULL) {
    if (exec->counts != NULL) {
        int i;

        for (i = 0;i < exec->maxRollbacks;i++)
        if (exec->rollbacks[i].counts != NULL)
            xmlFree(exec->rollbacks[i].counts);
    }
    xmlFree(exec->rollbacks);
    }
    if (exec->counts != NULL)
    xmlFree(exec->counts);
    if (exec->status == 0)
    return(1);
    if (exec->status == -1) {
    if (exec->nbPush > MAX_PUSH)
        return(-1);
    return(0);
    }
    return(exec->status);
}

/************************************************************************
 *                                  *
 *  Progressive interface to the verifier one atom at a time    *
 *                                  *
 ************************************************************************/
#ifdef DEBUG_ERR
static void testerr(xmlRegExecCtxtPtr exec);
#endif

xmlRegExecCtxtPtr
xmlRegNewExecCtxt(xmlRegexpPtr comp, xmlRegExecCallbacks callback, void *data) {
    xmlRegExecCtxtPtr exec;

    if (comp == NULL)
    return(NULL);
    if ((comp->compact == NULL) && (comp->states == NULL))
        return(NULL);
    exec = (xmlRegExecCtxtPtr) xmlMalloc(sizeof(xmlRegExecCtxt));
    if (exec == NULL) {
    xmlRegexpErrMemory(NULL, "creating execution context");
    return(NULL);
    }
    memset(exec, 0, sizeof(xmlRegExecCtxt));
    exec->inputString = NULL;
    exec->index = 0;
    exec->determinist = 1;
    exec->maxRollbacks = 0;
    exec->nbRollbacks = 0;
    exec->rollbacks = NULL;
    exec->status = 0;
    exec->comp = comp;
    if (comp->compact == NULL)
    exec->state = comp->states[0];
    exec->transno = 0;
    exec->transcount = 0;
    exec->callback = callback;
    exec->data = data;
    if (comp->nbCounters > 0) {
        /*
     * For error handling, exec->counts is allocated twice the size
     * the second half is used to store the data in case of rollback
     */
    exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int)
                                     * 2);
    if (exec->counts == NULL) {
        xmlRegexpErrMemory(NULL, "creating execution context");
        xmlFree(exec);
        return(NULL);
    }
        memset(exec->counts, 0, comp->nbCounters * sizeof(int) * 2);
    exec->errCounts = &exec->counts[comp->nbCounters];
    } else {
    exec->counts = NULL;
    exec->errCounts = NULL;
    }
    exec->inputStackMax = 0;
    exec->inputStackNr = 0;
    exec->inputStack = NULL;
    exec->errStateNo = -1;
    exec->errString = NULL;
    exec->nbPush = 0;
    return(exec);
}

void
xmlRegFreeExecCtxt(xmlRegExecCtxtPtr exec) {
    if (exec == NULL)
    return;

    if (exec->rollbacks != NULL) {
    if (exec->counts != NULL) {
        int i;

        for (i = 0;i < exec->maxRollbacks;i++)
        if (exec->rollbacks[i].counts != NULL)
            xmlFree(exec->rollbacks[i].counts);
    }
    xmlFree(exec->rollbacks);
    }
    if (exec->counts != NULL)
    xmlFree(exec->counts);
    if (exec->inputStack != NULL) {
    int i;

    for (i = 0;i < exec->inputStackNr;i++) {
        if (exec->inputStack[i].value != NULL)
        xmlFree(exec->inputStack[i].value);
    }
    xmlFree(exec->inputStack);
    }
    if (exec->errString != NULL)
        xmlFree(exec->errString);
    xmlFree(exec);
}

static void
xmlFARegExecSaveInputString(xmlRegExecCtxtPtr exec, const xmlChar *value,
                        void *data) {
#ifdef DEBUG_PUSH
    printf("saving value: %d:%s\n", exec->inputStackNr, value);
#endif
    if (exec->inputStackMax == 0) {
    exec->inputStackMax = 4;
    exec->inputStack = (xmlRegInputTokenPtr) 
        xmlMalloc(exec->inputStackMax * sizeof(xmlRegInputToken));
    if (exec->inputStack == NULL) {
        xmlRegexpErrMemory(NULL, "pushing input string");
        exec->inputStackMax = 0;
        return;
    }
    } else if (exec->inputStackNr + 1 >= exec->inputStackMax) {
    xmlRegInputTokenPtr tmp;

    exec->inputStackMax *= 2;
    tmp = (xmlRegInputTokenPtr) xmlRealloc(exec->inputStack,
            exec->inputStackMax * sizeof(xmlRegInputToken));
    if (tmp == NULL) {
        xmlRegexpErrMemory(NULL, "pushing input string");
        exec->inputStackMax /= 2;
        return;
    }
    exec->inputStack = tmp;
    }
    exec->inputStack[exec->inputStackNr].value = xmlStrdup(value);
    exec->inputStack[exec->inputStackNr].data = data;
    exec->inputStackNr++;
    exec->inputStack[exec->inputStackNr].value = NULL;
    exec->inputStack[exec->inputStackNr].data = NULL;
}

static int
xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr) {
    if (expStr == valStr) return(1);
    if (expStr == NULL) return(0);
    if (valStr == NULL) return(0);
    do {
    /*
    * Eval if we have a wildcard for the current item.
    */
        if (*expStr != *valStr) {
        /* if one of them starts with a wildcard make valStr be it */
        if (*valStr == '*') {
            const xmlChar *tmp;

        tmp = valStr;
        valStr = expStr;
        expStr = tmp;
        }
        if ((*valStr != 0) && (*expStr != 0) && (*expStr++ == '*')) {
        do {
            if (*valStr == XML_REG_STRING_SEPARATOR)
            break;
            valStr++;
        } while (*valStr != 0);
        continue;
        } else
        return(0);
    }
    expStr++;
    valStr++;
    } while (*valStr != 0);
    if (*expStr != 0)
    return (0);
    else
    return (1);
}

static int
xmlRegCompactPushString(xmlRegExecCtxtPtr exec,
                    xmlRegexpPtr comp,
                    const xmlChar *value,
                    void *data) {
    int state = exec->index;
    int i, target;

    if ((comp == NULL) || (comp->compact == NULL) || (comp->stringMap == NULL))
    return(-1);
    
    if (value == NULL) {
    /*
     * are we at a final state ?
     */
    if (comp->compact[state * (comp->nbstrings + 1)] ==
            XML_REGEXP_FINAL_STATE)
        return(1);
    return(0);
    }

#ifdef DEBUG_PUSH
    printf("value pushed: %s\n", value);
#endif

    /*
     * Examine all outside transitions from current state
     */
    for (i = 0;i < comp->nbstrings;i++) {
    target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
    if ((target > 0) && (target <= comp->nbstates)) {
        target--; /* to avoid 0 */    
        if (xmlRegStrEqualWildcard(comp->stringMap[i], value)) {
        exec->index = target;       
        if ((exec->callback != NULL) && (comp->transdata != NULL)) {
            exec->callback(exec->data, value,
              comp->transdata[state * comp->nbstrings + i], data);
        }
#ifdef DEBUG_PUSH
        printf("entering state %d\n", target);
#endif
        if (comp->compact[target * (comp->nbstrings + 1)] ==
            XML_REGEXP_SINK_STATE)
            goto error;

        if (comp->compact[target * (comp->nbstrings + 1)] ==
            XML_REGEXP_FINAL_STATE)
            return(1);
        return(0);
        }
    }
    }
    /*
     * Failed to find an exit transition out from current state for the
     * current token
     */
#ifdef DEBUG_PUSH
    printf("failed to find a transition for %s on state %d\n", value, state);
#endif
error:
    if (exec->errString != NULL)
        xmlFree(exec->errString);
    exec->errString = xmlStrdup(value);
    exec->errStateNo = state;
    exec->status = -1;
#ifdef DEBUG_ERR
    testerr(exec);
#endif
    return(-1);
}

static int
xmlRegExecPushStringInternal(xmlRegExecCtxtPtr exec, const xmlChar *value,
                         void *data, int compound) {
    xmlRegTransPtr trans;
    xmlRegAtomPtr atom;
    int ret;
    int final = 0;
    int progress = 1;

    if (exec == NULL)
    return(-1);
    if (exec->comp == NULL)
    return(-1);
    if (exec->status != 0)
    return(exec->status);

    if (exec->comp->compact != NULL)
    return(xmlRegCompactPushString(exec, exec->comp, value, data));

    if (value == NULL) {
        if (exec->state->type == XML_REGEXP_FINAL_STATE)
        return(1);
    final = 1;
    }

#ifdef DEBUG_PUSH
    printf("value pushed: %s\n", value);
#endif
    /*
     * If we have an active rollback stack push the new value there
     * and get back to where we were left
     */
    if ((value != NULL) && (exec->inputStackNr > 0)) {
    xmlFARegExecSaveInputString(exec, value, data);
    value = exec->inputStack[exec->index].value;
    data = exec->inputStack[exec->index].data;
#ifdef DEBUG_PUSH
    printf("value loaded: %s\n", value);
#endif
    }

    while ((exec->status == 0) &&
       ((value != NULL) ||
        ((final == 1) &&
         (exec->state->type != XML_REGEXP_FINAL_STATE)))) {

    /*
     * End of input on non-terminal state, rollback, however we may
     * still have epsilon like transition for counted transitions
     * on counters, in that case don't break too early.
     */
    if ((value == NULL) && (exec->counts == NULL))
        goto rollback;

    exec->transcount = 0;
    for (;exec->transno < exec->state->nbTrans;exec->transno++) {
        trans = &exec->state->trans[exec->transno];
        if (trans->to < 0)
        continue;
        atom = trans->atom;
        ret = 0;
        if (trans->count == REGEXP_ALL_LAX_COUNTER) {
        int i;
        int count;
        xmlRegTransPtr t;
        xmlRegCounterPtr counter;

        ret = 0;

#ifdef DEBUG_PUSH
        printf("testing all lax %d\n", trans->count);
#endif
        /*
         * Check all counted transitions from the current state
         */
        if ((value == NULL) && (final)) {
            ret = 1;
        } else if (value != NULL) {
            for (i = 0;i < exec->state->nbTrans;i++) {
            t = &exec->state->trans[i];
            if ((t->counter < 0) || (t == trans))
                continue;
            counter = &exec->comp->counters[t->counter];
            count = exec->counts[t->counter];
            if ((count < counter->max) && 
                    (t->atom != NULL) &&
                (xmlStrEqual(value, t->atom->valuep))) {
                ret = 0;
                break;
            }
            if ((count >= counter->min) &&
                (count < counter->max) &&
                (t->atom != NULL) &&
                (xmlStrEqual(value, t->atom->valuep))) {
                ret = 1;
                break;
            }
            }
        }
        } else if (trans->count == REGEXP_ALL_COUNTER) {
        int i;
        int count;
        xmlRegTransPtr t;
        xmlRegCounterPtr counter;

        ret = 1;

#ifdef DEBUG_PUSH
        printf("testing all %d\n", trans->count);
#endif
        /*
         * Check all counted transitions from the current state
         */
        for (i = 0;i < exec->state->nbTrans;i++) {
                    t = &exec->state->trans[i];
            if ((t->counter < 0) || (t == trans))
            continue;
                    counter = &exec->comp->counters[t->counter];
            count = exec->counts[t->counter];
            if ((count < counter->min) || (count > counter->max)) {
            ret = 0;
            break;
            }
        }
        } else if (trans->count >= 0) {
        int count;
        xmlRegCounterPtr counter;

        /*
         * A counted transition.
         */

        count = exec->counts[trans->count];
        counter = &exec->comp->counters[trans->count];
#ifdef DEBUG_PUSH
        printf("testing count %d: val %d, min %d, max %d\n",
               trans->count, count, counter->min,  counter->max);
#endif
        ret = ((count >= counter->min) && (count <= counter->max));
        } else if (atom == NULL) {
        fprintf(stderr, "epsilon transition left at runtime\n");
        exec->status = -2;
        break;
        } else if (value != NULL) {
        ret = xmlRegStrEqualWildcard(atom->valuep, value);
        if (atom->neg) {
            ret = !ret;
            if (!compound)
                ret = 0;
        }
        if ((ret == 1) && (trans->counter >= 0)) {
            xmlRegCounterPtr counter;
            int count;

            count = exec->counts[trans->counter];
            counter = &exec->comp->counters[trans->counter];
            if (count >= counter->max)
            ret = 0;
        }

        if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) {
            xmlRegStatePtr to = exec->comp->states[trans->to];

            /*
             * this is a multiple input sequence
             */
            if (exec->state->nbTrans > exec->transno + 1) {
            if (exec->inputStackNr <= 0) {
                xmlFARegExecSaveInputString(exec, value, data);
            }
            xmlFARegExecSave(exec);
            }
            exec->transcount = 1;
            do {
            /*
             * Try to progress as much as possible on the input
             */
            if (exec->transcount == atom->max) {
                break;
            }
            exec->index++;
            value = exec->inputStack[exec->index].value;
            data = exec->inputStack[exec->index].data;
#ifdef DEBUG_PUSH
            printf("value loaded: %s\n", value);
#endif

            /*
             * End of input: stop here
             */
            if (value == NULL) {
                exec->index --;
                break;
            }
            if (exec->transcount >= atom->min) {
                int transno = exec->transno;
                xmlRegStatePtr state = exec->state;

                /*
                 * The transition is acceptable save it
                 */
                exec->transno = -1; /* trick */
                exec->state = to;
                if (exec->inputStackNr <= 0) {
                xmlFARegExecSaveInputString(exec, value, data);
                }
                xmlFARegExecSave(exec);
                exec->transno = transno;
                exec->state = state;
            }
            ret = xmlStrEqual(value, atom->valuep);
            exec->transcount++;
            } while (ret == 1);
            if (exec->transcount < atom->min)
            ret = 0;

            /*
             * If the last check failed but one transition was found
             * possible, rollback
             */
            if (ret < 0)
            ret = 0;
            if (ret == 0) {
            goto rollback;
            }
        }
        }
        if (ret == 1) {
        if ((exec->callback != NULL) && (atom != NULL) &&
            (data != NULL)) {
            exec->callback(exec->data, atom->valuep,
                       atom->data, data);
        }
        if (exec->state->nbTrans > exec->transno + 1) {
            if (exec->inputStackNr <= 0) {
            xmlFARegExecSaveInputString(exec, value, data);
            }
            xmlFARegExecSave(exec);
        }
        if (trans->counter >= 0) {
#ifdef DEBUG_PUSH
            printf("Increasing count %d\n", trans->counter);
#endif
            exec->counts[trans->counter]++;
        }
        if ((trans->count >= 0) &&
            (trans->count < REGEXP_ALL_COUNTER)) {
#ifdef DEBUG_REGEXP_EXEC
            printf("resetting count %d on transition\n",
                   trans->count);
#endif
            exec->counts[trans->count] = 0;
        }
#ifdef DEBUG_PUSH
        printf("entering state %d\n", trans->to);
#endif
                if ((exec->comp->states[trans->to] != NULL) &&
            (exec->comp->states[trans->to]->type ==
             XML_REGEXP_SINK_STATE)) {
            /*
             * entering a sink state, save the current state as error
             * state.
             */
            if (exec->errString != NULL)
            xmlFree(exec->errString);
            exec->errString = xmlStrdup(value);
            exec->errState = exec->state;
            memcpy(exec->errCounts, exec->counts,
               exec->comp->nbCounters * sizeof(int));
        }
        exec->state = exec->comp->states[trans->to];
        exec->transno = 0;
        if (trans->atom != NULL) {
            if (exec->inputStack != NULL) {
            exec->index++;
            if (exec->index < exec->inputStackNr) {
                value = exec->inputStack[exec->index].value;
                data = exec->inputStack[exec->index].data;
#ifdef DEBUG_PUSH
                printf("value loaded: %s\n", value);
#endif
            } else {
                value = NULL;
                data = NULL;
#ifdef DEBUG_PUSH
                printf("end of input\n");
#endif
            }
            } else {
            value = NULL;
            data = NULL;
#ifdef DEBUG_PUSH
            printf("end of input\n");
#endif
            }
        }
        goto progress;
        } else if (ret < 0) {
        exec->status = -4;
        break;
        }
    }
    if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
rollback:
            /*
         * if we didn't yet rollback on the current input
         * store the current state as the error state.
         */
        if ((progress) && (exec->state != NULL) &&
            (exec->state->type != XML_REGEXP_SINK_STATE)) {
            progress = 0;
        if (exec->errString != NULL)
            xmlFree(exec->errString);
        exec->errString = xmlStrdup(value);
        exec->errState = exec->state;
        memcpy(exec->errCounts, exec->counts,
               exec->comp->nbCounters * sizeof(int));
        }

        /*
         * Failed to find a way out
         */
        exec->determinist = 0;
        xmlFARegExecRollBack(exec);
        if (exec->status == 0) {
        value = exec->inputStack[exec->index].value;
        data = exec->inputStack[exec->index].data;
#ifdef DEBUG_PUSH
        printf("value loaded: %s\n", value);
#endif
        }
    }
    continue;
progress:
        progress = 1;
    continue;
    }
    if (exec->status == 0) {
        return(exec->state->type == XML_REGEXP_FINAL_STATE);
    }
#ifdef DEBUG_ERR
    if (exec->status < 0) {
    testerr(exec);
    }
#endif
    return(exec->status);
}

int
xmlRegExecPushString(xmlRegExecCtxtPtr exec, const xmlChar *value,
                 void *data) {
    return(xmlRegExecPushStringInternal(exec, value, data, 0));
}

int
xmlRegExecPushString2(xmlRegExecCtxtPtr exec, const xmlChar *value,
                      const xmlChar *value2, void *data) {
    xmlChar buf[150];
    int lenn, lenp, ret;
    xmlChar *str;

    if (exec == NULL)
    return(-1);
    if (exec->comp == NULL)
    return(-1);
    if (exec->status != 0)
    return(exec->status);

    if (value2 == NULL)
        return(xmlRegExecPushString(exec, value, data));

    lenn = strlen((char *) value2);
    lenp = strlen((char *) value);

    if (150 < lenn + lenp + 2) {
    str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
    if (str == NULL) {
        exec->status = -1;
        return(-1);
    }
    } else {
    str = buf;
    }
    memcpy(&str[0], value, lenp);
    str[lenp] = XML_REG_STRING_SEPARATOR;
    memcpy(&str[lenp + 1], value2, lenn);
    str[lenn + lenp + 1] = 0;

    if (exec->comp->compact != NULL)
    ret = xmlRegCompactPushString(exec, exec->comp, str, data);
    else
        ret = xmlRegExecPushStringInternal(exec, str, data, 1);

    if (str != buf)
        xmlFree(str);
    return(ret);
}

static int
xmlRegExecGetValues(xmlRegExecCtxtPtr exec, int err,
                    int *nbval, int *nbneg,
            xmlChar **values, int *terminal) {
    int maxval;
    int nb = 0;

    if ((exec == NULL) || (nbval == NULL) || (nbneg == NULL) || 
        (values == NULL) || (*nbval <= 0))
        return(-1);

    maxval = *nbval;
    *nbval = 0;
    *nbneg = 0;
    if ((exec->comp != NULL) && (exec->comp->compact != NULL)) {
        xmlRegexpPtr comp;
    int target, i, state;

        comp = exec->comp;

    if (err) {
        if (exec->errStateNo == -1) return(-1);
        state = exec->errStateNo;
    } else {
        state = exec->index;
    }
    if (terminal != NULL) {
        if (comp->compact[state * (comp->nbstrings + 1)] ==
            XML_REGEXP_FINAL_STATE)
        *terminal = 1;
        else
        *terminal = 0;
    }
    for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) {
        target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
        if ((target > 0) && (target <= comp->nbstates) &&
            (comp->compact[(target - 1) * (comp->nbstrings + 1)] !=
         XML_REGEXP_SINK_STATE)) {
            values[nb++] = comp->stringMap[i];
        (*nbval)++;
        }
    }
    for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) {
        target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
        if ((target > 0) && (target <= comp->nbstates) &&
            (comp->compact[(target - 1) * (comp->nbstrings + 1)] ==
         XML_REGEXP_SINK_STATE)) {
            values[nb++] = comp->stringMap[i];
        (*nbneg)++;
        }
    }
    } else {
        int transno;
    xmlRegTransPtr trans;
    xmlRegAtomPtr atom;
    xmlRegStatePtr state;

    if (terminal != NULL) {
        if (exec->state->type == XML_REGEXP_FINAL_STATE)
        *terminal = 1;
        else
        *terminal = 0;
    }

    if (err) {
        if (exec->errState == NULL) return(-1);
        state = exec->errState;
    } else {
        if (exec->state == NULL) return(-1);
        state = exec->state;
    }
    for (transno = 0;
         (transno < state->nbTrans) && (nb < maxval);
         transno++) {
        trans = &state->trans[transno];
        if (trans->to < 0)
        continue;
        atom = trans->atom;
        if ((atom == NULL) || (atom->valuep == NULL))
        continue;
        if (trans->count == REGEXP_ALL_LAX_COUNTER) {
            /* this should not be reached but ... */
            TODO;
        } else if (trans->count == REGEXP_ALL_COUNTER) {
            /* this should not be reached but ... */
            TODO;
        } else if (trans->counter >= 0) {
        xmlRegCounterPtr counter = NULL;
        int count;

        if (err)
            count = exec->errCounts[trans->counter];
        else
            count = exec->counts[trans->counter];
        if (exec->comp != NULL)
            counter = &exec->comp->counters[trans->counter];
        if ((counter == NULL) || (count < counter->max)) {
            if (atom->neg)
            values[nb++] = (xmlChar *) atom->valuep2;
            else
            values[nb++] = (xmlChar *) atom->valuep;
            (*nbval)++;
        }
        } else {
                if ((exec->comp->states[trans->to] != NULL) &&
            (exec->comp->states[trans->to]->type !=
             XML_REGEXP_SINK_STATE)) {
            if (atom->neg)
            values[nb++] = (xmlChar *) atom->valuep2;
            else
            values[nb++] = (xmlChar *) atom->valuep;
            (*nbval)++;
        }
        } 
    }
    for (transno = 0;
         (transno < state->nbTrans) && (nb < maxval);
         transno++) {
        trans = &state->trans[transno];
        if (trans->to < 0)
        continue;
        atom = trans->atom;
        if ((atom == NULL) || (atom->valuep == NULL))
        continue;
        if (trans->count == REGEXP_ALL_LAX_COUNTER) {
            continue;
        } else if (trans->count == REGEXP_ALL_COUNTER) {
            continue;
        } else if (trans->counter >= 0) {
            continue;
        } else {
                if ((exec->comp->states[trans->to] != NULL) &&
            (exec->comp->states[trans->to]->type ==
             XML_REGEXP_SINK_STATE)) {
            if (atom->neg)
            values[nb++] = (xmlChar *) atom->valuep2;
            else
            values[nb++] = (xmlChar *) atom->valuep;
            (*nbneg)++;
        }
        } 
    }
    }
    return(0);
}

int
xmlRegExecNextValues(xmlRegExecCtxtPtr exec, int *nbval, int *nbneg,
                     xmlChar **values, int *terminal) {
    return(xmlRegExecGetValues(exec, 0, nbval, nbneg, values, terminal));
}

int
xmlRegExecErrInfo(xmlRegExecCtxtPtr exec, const xmlChar **string,
                  int *nbval, int *nbneg, xmlChar **values, int *terminal) {
    if (exec == NULL)
        return(-1);
    if (string != NULL) {
        if (exec->status != 0)
        *string = exec->errString;
    else
        *string = NULL;
    }
    return(xmlRegExecGetValues(exec, 1, nbval, nbneg, values, terminal));
}

#ifdef DEBUG_ERR
static void testerr(xmlRegExecCtxtPtr exec) {
    const xmlChar *string;
    xmlChar *values[5];
    int nb = 5;
    int nbneg;
    int terminal;
    xmlRegExecErrInfo(exec, &string, &nb, &nbneg, &values[0], &terminal);
}
#endif

#if 0
static int
xmlRegExecPushChar(xmlRegExecCtxtPtr exec, int UCS) {
    xmlRegTransPtr trans;
    xmlRegAtomPtr atom;
    int ret;
    int codepoint, len;

    if (exec == NULL)
    return(-1);
    if (exec->status != 0)
    return(exec->status);

    while ((exec->status == 0) &&
       ((exec->inputString[exec->index] != 0) ||
        (exec->state->type != XML_REGEXP_FINAL_STATE))) {

    /*
     * End of input on non-terminal state, rollback, however we may
     * still have epsilon like transition for counted transitions
     * on counters, in that case don't break too early.
     */
    if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL))
        goto rollback;

    exec->transcount = 0;
    for (;exec->transno < exec->state->nbTrans;exec->transno++) {
        trans = &exec->state->trans[exec->transno];
        if (trans->to < 0)
        continue;
        atom = trans->atom;
        ret = 0;
        if (trans->count >= 0) {
        int count;
        xmlRegCounterPtr counter;

        /*
         * A counted transition.
         */

        count = exec->counts[trans->count];
        counter = &exec->comp->counters[trans->count];
#ifdef DEBUG_REGEXP_EXEC
        printf("testing count %d: val %d, min %d, max %d\n",
               trans->count, count, counter->min,  counter->max);
#endif
        ret = ((count >= counter->min) && (count <= counter->max));
        } else if (atom == NULL) {
        fprintf(stderr, "epsilon transition left at runtime\n");
        exec->status = -2;
        break;
        } else if (exec->inputString[exec->index] != 0) {
                codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len);
        ret = xmlRegCheckCharacter(atom, codepoint);
        if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) {
            xmlRegStatePtr to = exec->comp->states[trans->to];

            /*
             * this is a multiple input sequence
             */
            if (exec->state->nbTrans > exec->transno + 1) {
            xmlFARegExecSave(exec);
            }
            exec->transcount = 1;
            do {
            /*
             * Try to progress as much as possible on the input
             */
            if (exec->transcount == atom->max) {
                break;
            }
            exec->index += len;
            /*
             * End of input: stop here
             */
            if (exec->inputString[exec->index] == 0) {
                exec->index -= len;
                break;
            }
            if (exec->transcount >= atom->min) {
                int transno = exec->transno;
                xmlRegStatePtr state = exec->state;

                /*
                 * The transition is acceptable save it
                 */
                exec->transno = -1; /* trick */
                exec->state = to;
                xmlFARegExecSave(exec);
                exec->transno = transno;
                exec->state = state;
            }
            codepoint = CUR_SCHAR(&(exec->inputString[exec->index]),
                              len);
            ret = xmlRegCheckCharacter(atom, codepoint);
            exec->transcount++;
            } while (ret == 1);
            if (exec->transcount < atom->min)
            ret = 0;

            /*
             * If the last check failed but one transition was found
             * possible, rollback
             */
            if (ret < 0)
            ret = 0;
            if (ret == 0) {
            goto rollback;
            }
        }
        }
        if (ret == 1) {
        if (exec->state->nbTrans > exec->transno + 1) {
            xmlFARegExecSave(exec);
        }
        /*
         * restart count for expressions like this ((abc){2})*
         */
        if (trans->count >= 0) {
#ifdef DEBUG_REGEXP_EXEC
            printf("Reset count %d\n", trans->count);
#endif
            exec->counts[trans->count] = 0;
        }
        if (trans->counter >= 0) {
#ifdef DEBUG_REGEXP_EXEC
            printf("Increasing count %d\n", trans->counter);
#endif
            exec->counts[trans->counter]++;
        }
#ifdef DEBUG_REGEXP_EXEC
        printf("entering state %d\n", trans->to);
#endif
        exec->state = exec->comp->states[trans->to];
        exec->transno = 0;
        if (trans->atom != NULL) {
            exec->index += len;
        }
        goto progress;
        } else if (ret < 0) {
        exec->status = -4;
        break;
        }
    }
    if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
rollback:
        /*
         * Failed to find a way out
         */
        exec->determinist = 0;
        xmlFARegExecRollBack(exec);
    }
progress:
    continue;
    }
}
#endif
/************************************************************************
 *                                  *
 *  Parser for the Schemas Datatype Regular Expressions     *
 *  http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/#regexs  *
 *                                  *
 ************************************************************************/

static int
xmlFAIsChar(xmlRegParserCtxtPtr ctxt) {
    int cur;
    int len;

    cur = CUR_SCHAR(ctxt->cur, len);
    if ((cur == '.') || (cur == '\\') || (cur == '?') ||
    (cur == '*') || (cur == '+') || (cur == '(') ||
    (cur == ')') || (cur == '|') || (cur == 0x5B) ||
    (cur == 0x5D) || (cur == 0))
    return(-1);
    return(cur);
}

static void
xmlFAParseCharProp(xmlRegParserCtxtPtr ctxt) {
    int cur;
    xmlRegAtomType type = (xmlRegAtomType) 0;
    xmlChar *blockName = NULL;
    
    cur = CUR;
    if (cur == 'L') {
    NEXT;
    cur = CUR;
    if (cur == 'u') {
        NEXT;
        type = XML_REGEXP_LETTER_UPPERCASE;
    } else if (cur == 'l') {
        NEXT;
        type = XML_REGEXP_LETTER_LOWERCASE;
    } else if (cur == 't') {
        NEXT;
        type = XML_REGEXP_LETTER_TITLECASE;
    } else if (cur == 'm') {
        NEXT;
        type = XML_REGEXP_LETTER_MODIFIER;
    } else if (cur == 'o') {
        NEXT;
        type = XML_REGEXP_LETTER_OTHERS;
    } else {
        type = XML_REGEXP_LETTER;
    }
    } else if (cur == 'M') {
    NEXT;
    cur = CUR;
    if (cur == 'n') {
        NEXT;
        /* nonspacing */
        type = XML_REGEXP_MARK_NONSPACING;
    } else if (cur == 'c') {
        NEXT;
        /* spacing combining */
        type = XML_REGEXP_MARK_SPACECOMBINING;
    } else if (cur == 'e') {
        NEXT;
        /* enclosing */
        type = XML_REGEXP_MARK_ENCLOSING;
    } else {
        /* all marks */
        type = XML_REGEXP_MARK;
    }
    } else if (cur == 'N') {
    NEXT;
    cur = CUR;
    if (cur == 'd') {
        NEXT;
        /* digital */
        type = XML_REGEXP_NUMBER_DECIMAL;
    } else if (cur == 'l') {
        NEXT;
        /* letter */
        type = XML_REGEXP_NUMBER_LETTER;
    } else if (cur == 'o') {
        NEXT;
        /* other */
        type = XML_REGEXP_NUMBER_OTHERS;
    } else {
        /* all numbers */
        type = XML_REGEXP_NUMBER;
    }
    } else if (cur == 'P') {
    NEXT;
    cur = CUR;
    if (cur == 'c') {
        NEXT;
        /* connector */
        type = XML_REGEXP_PUNCT_CONNECTOR;
    } else if (cur == 'd') {
        NEXT;
        /* dash */
        type = XML_REGEXP_PUNCT_DASH;
    } else if (cur == 's') {
        NEXT;
        /* open */
        type = XML_REGEXP_PUNCT_OPEN;
    } else if (cur == 'e') {
        NEXT;
        /* close */
        type = XML_REGEXP_PUNCT_CLOSE;
    } else if (cur == 'i') {
        NEXT;
        /* initial quote */
        type = XML_REGEXP_PUNCT_INITQUOTE;
    } else if (cur == 'f') {
        NEXT;
        /* final quote */
        type = XML_REGEXP_PUNCT_FINQUOTE;
    } else if (cur == 'o') {
        NEXT;
        /* other */
        type = XML_REGEXP_PUNCT_OTHERS;
    } else {
        /* all punctuation */
        type = XML_REGEXP_PUNCT;
    }
    } else if (cur == 'Z') {
    NEXT;
    cur = CUR;
    if (cur == 's') {
        NEXT;
        /* space */
        type = XML_REGEXP_SEPAR_SPACE;
    } else if (cur == 'l') {
        NEXT;
        /* line */
        type = XML_REGEXP_SEPAR_LINE;
    } else if (cur == 'p') {
        NEXT;
        /* paragraph */
        type = XML_REGEXP_SEPAR_PARA;
    } else {
        /* all separators */
        type = XML_REGEXP_SEPAR;
    }
    } else if (cur == 'S') {
    NEXT;
    cur = CUR;
    if (cur == 'm') {
        NEXT;
        type = XML_REGEXP_SYMBOL_MATH;
        /* math */
    } else if (cur == 'c') {
        NEXT;
        type = XML_REGEXP_SYMBOL_CURRENCY;
        /* currency */
    } else if (cur == 'k') {
        NEXT;
        type = XML_REGEXP_SYMBOL_MODIFIER;
        /* modifiers */
    } else if (cur == 'o') {
        NEXT;
        type = XML_REGEXP_SYMBOL_OTHERS;
        /* other */
    } else {
        /* all symbols */
        type = XML_REGEXP_SYMBOL;
    }
    } else if (cur == 'C') {
    NEXT;
    cur = CUR;
    if (cur == 'c') {
        NEXT;
        /* control */
        type = XML_REGEXP_OTHER_CONTROL;
    } else if (cur == 'f') {
        NEXT;
        /* format */
        type = XML_REGEXP_OTHER_FORMAT;
    } else if (cur == 'o') {
        NEXT;
        /* private use */
        type = XML_REGEXP_OTHER_PRIVATE;
    } else if (cur == 'n') {
        NEXT;
        /* not assigned */
        type = XML_REGEXP_OTHER_NA;
    } else {
        /* all others */
        type = XML_REGEXP_OTHER;
    }
    } else if (cur == 'I') {
    const xmlChar *start;
    NEXT;
    cur = CUR;
    if (cur != 's') {
        ERROR("IsXXXX expected");
        return;
    }
    NEXT;
    start = ctxt->cur;
    cur = CUR;
    if (((cur >= 'a') && (cur <= 'z')) || 
        ((cur >= 'A') && (cur <= 'Z')) || 
        ((cur >= '0') && (cur <= '9')) || 
        (cur == 0x2D)) {
        NEXT;
        cur = CUR;
        while (((cur >= 'a') && (cur <= 'z')) || 
        ((cur >= 'A') && (cur <= 'Z')) || 
        ((cur >= '0') && (cur <= '9')) || 
        (cur == 0x2D)) {
        NEXT;
        cur = CUR;
        }
    }
    type = XML_REGEXP_BLOCK_NAME;
    blockName = xmlStrndup(start, ctxt->cur - start);
    } else {
    ERROR("Unknown char property");
    return;
    }
    if (ctxt->atom == NULL) {
    ctxt->atom = xmlRegNewAtom(ctxt, type);
    if (ctxt->atom != NULL)
        ctxt->atom->valuep = blockName;
    } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                   type, 0, 0, blockName);
    }
}

static void
xmlFAParseCharClassEsc(xmlRegParserCtxtPtr ctxt) {
    int cur;

    if (CUR == '.') {
    if (ctxt->atom == NULL) {
        ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_ANYCHAR);
    } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                   XML_REGEXP_ANYCHAR, 0, 0, NULL);
    }
    NEXT;
    return;
    }
    if (CUR != '\\') {
    ERROR("Escaped sequence: expecting \\");
    return;
    }
    NEXT;
    cur = CUR;
    if (cur == 'p') {
    NEXT;
    if (CUR != '{') {
        ERROR("Expecting '{'");
        return;
    }
    NEXT;
    xmlFAParseCharProp(ctxt);
    if (CUR != '}') {
        ERROR("Expecting '}'");
        return;
    }
    NEXT;
    } else if (cur == 'P') {
    NEXT;
    if (CUR != '{') {
        ERROR("Expecting '{'");
        return;
    }
    NEXT;
    xmlFAParseCharProp(ctxt);
    ctxt->atom->neg = 1;
    if (CUR != '}') {
        ERROR("Expecting '}'");
        return;
    }
    NEXT;
    } else if ((cur == 'n') || (cur == 'r') || (cur == 't') || (cur == '\\') ||
    (cur == '|') || (cur == '.') || (cur == '?') || (cur == '*') ||
    (cur == '+') || (cur == '(') || (cur == ')') || (cur == '{') ||
    (cur == '}') || (cur == 0x2D) || (cur == 0x5B) || (cur == 0x5D) ||
    (cur == 0x5E)) {
    if (ctxt->atom == NULL) {
        ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL);
        if (ctxt->atom != NULL) {
            switch (cur) {
            case 'n':
                ctxt->atom->codepoint = '\n';
            break;
            case 'r':
                ctxt->atom->codepoint = '\r';
            break;
            case 't':
                ctxt->atom->codepoint = '\t';
            break;
            default:
            ctxt->atom->codepoint = cur;
        }
        }
    } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
            switch (cur) {
                case 'n':
                    cur = '\n';
                    break;
                case 'r':
                    cur = '\r';
                    break;
                case 't':
                    cur = '\t';
                    break;
            }
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                   XML_REGEXP_CHARVAL, cur, cur, NULL);
    }
    NEXT;
    } else if ((cur == 's') || (cur == 'S') || (cur == 'i') || (cur == 'I') ||
    (cur == 'c') || (cur == 'C') || (cur == 'd') || (cur == 'D') ||
    (cur == 'w') || (cur == 'W')) {
    xmlRegAtomType type = XML_REGEXP_ANYSPACE;

    switch (cur) {
        case 's': 
        type = XML_REGEXP_ANYSPACE;
        break;
        case 'S': 
        type = XML_REGEXP_NOTSPACE;
        break;
        case 'i': 
        type = XML_REGEXP_INITNAME;
        break;
        case 'I': 
        type = XML_REGEXP_NOTINITNAME;
        break;
        case 'c': 
        type = XML_REGEXP_NAMECHAR;
        break;
        case 'C': 
        type = XML_REGEXP_NOTNAMECHAR;
        break;
        case 'd': 
        type = XML_REGEXP_DECIMAL;
        break;
        case 'D': 
        type = XML_REGEXP_NOTDECIMAL;
        break;
        case 'w': 
        type = XML_REGEXP_REALCHAR;
        break;
        case 'W': 
        type = XML_REGEXP_NOTREALCHAR;
        break;
    }
    NEXT;
    if (ctxt->atom == NULL) {
        ctxt->atom = xmlRegNewAtom(ctxt, type);
    } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                   type, 0, 0, NULL);
    }
    } else {
    ERROR("Wrong escape sequence, misuse of character '\\'");
    }
}

static void
xmlFAParseCharRange(xmlRegParserCtxtPtr ctxt) {
    int cur, len;
    int start = -1;
    int end = -1;

    if (CUR == '\0') {
        ERROR("Expecting ']'");
    return;
    }

    cur = CUR;
    if (cur == '\\') {
    NEXT;
    cur = CUR;
    switch (cur) {
        case 'n': start = 0xA; break;
        case 'r': start = 0xD; break;
        case 't': start = 0x9; break;
        case '\\': case '|': case '.': case '-': case '^': case '?':
        case '*': case '+': case '{': case '}': case '(': case ')':
        case '[': case ']':
        start = cur; break;
        default:
        ERROR("Invalid escape value");
        return;
    }
    end = start;
        len = 1;
    } else if ((cur != 0x5B) && (cur != 0x5D)) {
        end = start = CUR_SCHAR(ctxt->cur, len);
    } else {
    ERROR("Expecting a char range");
    return;
    }
    /*
     * Since we are "inside" a range, we can assume ctxt->cur is past
     * the start of ctxt->string, and PREV should be safe
     */
    if ((start == '-') && (NXT(1) != ']') && (PREV != '[') && (PREV != '^')) {
    NEXTL(len);
    return;
    }
    NEXTL(len);
    cur = CUR;
    if ((cur != '-') || (NXT(1) == ']')) {
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                      XML_REGEXP_CHARVAL, start, end, NULL);
    return;
    }
    NEXT;
    cur = CUR;
    if (cur == '\\') {
    NEXT;
    cur = CUR;
    switch (cur) {
        case 'n': end = 0xA; break;
        case 'r': end = 0xD; break;
        case 't': end = 0x9; break;
        case '\\': case '|': case '.': case '-': case '^': case '?':
        case '*': case '+': case '{': case '}': case '(': case ')':
        case '[': case ']':
        end = cur; break;
        default:
        ERROR("Invalid escape value");
        return;
    }
        len = 1;
    } else if ((cur != 0x5B) && (cur != 0x5D)) {
        end = CUR_SCHAR(ctxt->cur, len);
    } else {
    ERROR("Expecting the end of a char range");
    return;
    }
    NEXTL(len);
    /* TODO check that the values are acceptable character ranges for XML */
    if (end < start) {
    ERROR("End of range is before start of range");
    } else {
        xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
                   XML_REGEXP_CHARVAL, start, end, NULL);
    }
    return;
}

static void
xmlFAParsePosCharGroup(xmlRegParserCtxtPtr ctxt) {
    do {
    if (CUR == '\\') {
        xmlFAParseCharClassEsc(ctxt);
    } else {
        xmlFAParseCharRange(ctxt);
    }
    } while ((CUR != ']') && (CUR != '^') && (CUR != '-') &&
             (CUR != 0) && (ctxt->error == 0));
}

static void
xmlFAParseCharGroup(xmlRegParserCtxtPtr ctxt) {
    int n = ctxt->neg;
    while ((CUR != ']') && (ctxt->error == 0)) {
    if (CUR == '^') {
        int neg = ctxt->neg;

        NEXT;
        ctxt->neg = !ctxt->neg;
        xmlFAParsePosCharGroup(ctxt);
        ctxt->neg = neg;
    } else if ((CUR == '-') && (NXT(1) == '[')) {
        int neg = ctxt->neg;
        ctxt->neg = 2;
        NEXT;   /* eat the '-' */
        NEXT;   /* eat the '[' */
        xmlFAParseCharGroup(ctxt);
        if (CUR == ']') {
        NEXT;
        } else {
        ERROR("charClassExpr: ']' expected");
        break;
        }
        ctxt->neg = neg;
        break;
    } else if (CUR != ']') {
        xmlFAParsePosCharGroup(ctxt);
    }
    }
    ctxt->neg = n;
}

static void
xmlFAParseCharClass(xmlRegParserCtxtPtr ctxt) {
    if (CUR == '[') {
    NEXT;
    ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_RANGES);
    if (ctxt->atom == NULL)
        return;
    xmlFAParseCharGroup(ctxt);
    if (CUR == ']') {
        NEXT;
    } else {
        ERROR("xmlFAParseCharClass: ']' expected");
    }
    } else {
    xmlFAParseCharClassEsc(ctxt);
    }
}

static int
xmlFAParseQuantExact(xmlRegParserCtxtPtr ctxt) {
    int ret = 0;
    int ok = 0;

    while ((CUR >= '0') && (CUR <= '9')) {
    ret = ret * 10 + (CUR - '0');
    ok = 1;
    NEXT;
    }
    if (ok != 1) {
    return(-1);
    }
    return(ret);
}

static int
xmlFAParseQuantifier(xmlRegParserCtxtPtr ctxt) {
    int cur;

    cur = CUR;
    if ((cur == '?') || (cur == '*') || (cur == '+')) {
    if (ctxt->atom != NULL) {
        if (cur == '?')
        ctxt->atom->quant = XML_REGEXP_QUANT_OPT;
        else if (cur == '*')
        ctxt->atom->quant = XML_REGEXP_QUANT_MULT;
        else if (cur == '+')
        ctxt->atom->quant = XML_REGEXP_QUANT_PLUS;
    }
    NEXT;
    return(1);
    }
    if (cur == '{') {
    int min = 0, max = 0;

    NEXT;
    cur = xmlFAParseQuantExact(ctxt);
    if (cur >= 0)
        min = cur;
    if (CUR == ',') {
        NEXT;
        if (CUR == '}')
            max = INT_MAX;
        else {
            cur = xmlFAParseQuantExact(ctxt);
            if (cur >= 0)
            max = cur;
        else {
            ERROR("Improper quantifier");
        }
        }
    }
    if (CUR == '}') {
        NEXT;
    } else {
        ERROR("Unterminated quantifier");
    }
    if (max == 0)
        max = min;
    if (ctxt->atom != NULL) {
        ctxt->atom->quant = XML_REGEXP_QUANT_RANGE;
        ctxt->atom->min = min;
        ctxt->atom->max = max;
    }
    return(1);
    }
    return(0);
}

static int
xmlFAParseAtom(xmlRegParserCtxtPtr ctxt) {
    int codepoint, len;

    codepoint = xmlFAIsChar(ctxt);
    if (codepoint > 0) {
    ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL);
    if (ctxt->atom == NULL)
        return(-1);
    codepoint = CUR_SCHAR(ctxt->cur, len);
    ctxt->atom->codepoint = codepoint;
    NEXTL(len);
    return(1);
    } else if (CUR == '|') {
    return(0);
    } else if (CUR == 0) {
    return(0);
    } else if (CUR == ')') {
    return(0);
    } else if (CUR == '(') {
    xmlRegStatePtr start, oldend, start0;

    NEXT;
    /*
     * this extra Epsilon transition is needed if we count with 0 allowed
     * unfortunately this can't be known at that point
     */
    xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL);
    start0 = ctxt->state;
    xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL);
    start = ctxt->state;
    oldend = ctxt->end;
    ctxt->end = NULL;
    ctxt->atom = NULL;
    xmlFAParseRegExp(ctxt, 0);
    if (CUR == ')') {
        NEXT;
    } else {
        ERROR("xmlFAParseAtom: expecting ')'");
    }
    ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_SUBREG);
    if (ctxt->atom == NULL)
        return(-1);
    ctxt->atom->start = start;
    ctxt->atom->start0 = start0;
    ctxt->atom->stop = ctxt->state;
    ctxt->end = oldend;
    return(1);
    } else if ((CUR == '[') || (CUR == '\\') || (CUR == '.')) {
    xmlFAParseCharClass(ctxt);
    return(1);
    }
    return(0);
}

static int
xmlFAParsePiece(xmlRegParserCtxtPtr ctxt) {
    int ret;

    ctxt->atom = NULL;
    ret = xmlFAParseAtom(ctxt);
    if (ret == 0)
    return(0);
    if (ctxt->atom == NULL) {
    ERROR("internal: no atom generated");
    }
    xmlFAParseQuantifier(ctxt);
    return(1);
}

static int
xmlFAParseBranch(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr to) {
    xmlRegStatePtr previous;
    int ret;

    previous = ctxt->state;
    ret = xmlFAParsePiece(ctxt);
    if (ret != 0) {
    if (xmlFAGenerateTransitions(ctxt, previous, 
            (CUR=='|' || CUR==')') ? to : NULL, ctxt->atom) < 0)
        return(-1);
    previous = ctxt->state;
    ctxt->atom = NULL;
    }
    while ((ret != 0) && (ctxt->error == 0)) {
    ret = xmlFAParsePiece(ctxt);
    if (ret != 0) {
        if (xmlFAGenerateTransitions(ctxt, previous, 
                (CUR=='|' || CUR==')') ? to : NULL, ctxt->atom) < 0)
            return(-1);
        previous = ctxt->state;
        ctxt->atom = NULL;
    }
    }
    return(0);
}

static void
xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top) {
    xmlRegStatePtr start, end;

    /* if not top start should have been generated by an epsilon trans */
    start = ctxt->state;
    ctxt->end = NULL;
    xmlFAParseBranch(ctxt, NULL);
    if (top) {
#ifdef DEBUG_REGEXP_GRAPH
    printf("State %d is final\n", ctxt->state->no);
#endif
    ctxt->state->type = XML_REGEXP_FINAL_STATE;
    }
    if (CUR != '|') {
    ctxt->end = ctxt->state;
    return;
    }
    end = ctxt->state;
    while ((CUR == '|') && (ctxt->error == 0)) {
    NEXT;
    ctxt->state = start;
    ctxt->end = NULL;
    xmlFAParseBranch(ctxt, end);
    }
    if (!top) {
    ctxt->state = end;
    ctxt->end = end;
    }
}

/************************************************************************
 *                                  *
 *          The basic API                   *
 *                                  *
 ************************************************************************/

void
xmlRegexpPrint(FILE *output, xmlRegexpPtr regexp) {
    int i;

    if (output == NULL)
        return;
    fprintf(output, " regexp: ");
    if (regexp == NULL) {
    fprintf(output, "NULL\n");
    return;
    }
    fprintf(output, "'%s' ", regexp->string);
    fprintf(output, "\n");
    fprintf(output, "%d atoms:\n", regexp->nbAtoms);
    for (i = 0;i < regexp->nbAtoms; i++) {
    fprintf(output, " %02d ", i);
    xmlRegPrintAtom(output, regexp->atoms[i]);
    }
    fprintf(output, "%d states:", regexp->nbStates);
    fprintf(output, "\n");
    for (i = 0;i < regexp->nbStates; i++) {
    xmlRegPrintState(output, regexp->states[i]);
    }
    fprintf(output, "%d counters:\n", regexp->nbCounters);
    for (i = 0;i < regexp->nbCounters; i++) {
    fprintf(output, " %d: min %d max %d\n", i, regexp->counters[i].min,
                                        regexp->counters[i].max);
    }
}

xmlRegexpPtr
xmlRegexpCompile(const xmlChar *regexp) {
    xmlRegexpPtr ret;
    xmlRegParserCtxtPtr ctxt;

    ctxt = xmlRegNewParserCtxt(regexp);
    if (ctxt == NULL)
    return(NULL);

    /* initialize the parser */
    ctxt->end = NULL;
    ctxt->start = ctxt->state = xmlRegNewState(ctxt);
    xmlRegStatePush(ctxt, ctxt->start);

    /* parse the expression building an automata */
    xmlFAParseRegExp(ctxt, 1);
    if (CUR != 0) {
    ERROR("xmlFAParseRegExp: extra characters");
    }
    if (ctxt->error != 0) {
    xmlRegFreeParserCtxt(ctxt);
    return(NULL);
    }
    ctxt->end = ctxt->state;
    ctxt->start->type = XML_REGEXP_START_STATE;
    ctxt->end->type = XML_REGEXP_FINAL_STATE;

    /* remove the Epsilon except for counted transitions */
    xmlFAEliminateEpsilonTransitions(ctxt);


    if (ctxt->error != 0) {
    xmlRegFreeParserCtxt(ctxt);
    return(NULL);
    }
    ret = xmlRegEpxFromParse(ctxt);
    xmlRegFreeParserCtxt(ctxt);
    return(ret);
}

int
xmlRegexpExec(xmlRegexpPtr comp, const xmlChar *content) {
    if ((comp == NULL) || (content == NULL))
    return(-1);
    return(xmlFARegExec(comp, content));
}

int
xmlRegexpIsDeterminist(xmlRegexpPtr comp) {
    xmlAutomataPtr am;
    int ret;

    if (comp == NULL)
    return(-1);
    if (comp->determinist != -1)
    return(comp->determinist);

    am = xmlNewAutomata();
    if (am->states != NULL) {
    int i;

    for (i = 0;i < am->nbStates;i++)
        xmlRegFreeState(am->states[i]);
    xmlFree(am->states);
    }
    am->nbAtoms = comp->nbAtoms;
    am->atoms = comp->atoms;
    am->nbStates = comp->nbStates;
    am->states = comp->states;
    am->determinist = -1;
    am->flags = comp->flags;
    ret = xmlFAComputesDeterminism(am);
    am->atoms = NULL;
    am->states = NULL;
    xmlFreeAutomata(am);
    comp->determinist = ret;
    return(ret);
}

void
xmlRegFreeRegexp(xmlRegexpPtr regexp) {
    int i;
    if (regexp == NULL)
    return;

    if (regexp->string != NULL)
    xmlFree(regexp->string);
    if (regexp->states != NULL) {
    for (i = 0;i < regexp->nbStates;i++)
        xmlRegFreeState(regexp->states[i]);
    xmlFree(regexp->states);
    }
    if (regexp->atoms != NULL) {
    for (i = 0;i < regexp->nbAtoms;i++)
        xmlRegFreeAtom(regexp->atoms[i]);
    xmlFree(regexp->atoms);
    }
    if (regexp->counters != NULL)
    xmlFree(regexp->counters);
    if (regexp->compact != NULL)
    xmlFree(regexp->compact);
    if (regexp->transdata != NULL)
    xmlFree(regexp->transdata);
    if (regexp->stringMap != NULL) {
    for (i = 0; i < regexp->nbstrings;i++)
        xmlFree(regexp->stringMap[i]);
    xmlFree(regexp->stringMap);
    }

    xmlFree(regexp);
}

#ifdef LIBXML_AUTOMATA_ENABLED
/************************************************************************
 *                                  *
 *          The Automata interface              *
 *                                  *
 ************************************************************************/

xmlAutomataPtr
xmlNewAutomata(void) {
    xmlAutomataPtr ctxt;

    ctxt = xmlRegNewParserCtxt(NULL);
    if (ctxt == NULL)
    return(NULL);

    /* initialize the parser */
    ctxt->end = NULL;
    ctxt->start = ctxt->state = xmlRegNewState(ctxt);
    if (ctxt->start == NULL) {
    xmlFreeAutomata(ctxt);
    return(NULL);
    }
    ctxt->start->type = XML_REGEXP_START_STATE;
    if (xmlRegStatePush(ctxt, ctxt->start) < 0) {
        xmlRegFreeState(ctxt->start);
    xmlFreeAutomata(ctxt);
    return(NULL);
    }
    ctxt->flags = 0;

    return(ctxt);
}

void
xmlFreeAutomata(xmlAutomataPtr am) {
    if (am == NULL)
    return;
    xmlRegFreeParserCtxt(am);
}

void
xmlAutomataSetFlags(xmlAutomataPtr am, int flags) {
    if (am == NULL)
    return;
    am->flags |= flags;
}

xmlAutomataStatePtr
xmlAutomataGetInitState(xmlAutomataPtr am) {
    if (am == NULL)
    return(NULL);
    return(am->start);
}

int
xmlAutomataSetFinalState(xmlAutomataPtr am, xmlAutomataStatePtr state) {
    if ((am == NULL) || (state == NULL))
    return(-1);
    state->type = XML_REGEXP_FINAL_STATE;
    return(0);
}

xmlAutomataStatePtr
xmlAutomataNewTransition(xmlAutomataPtr am, xmlAutomataStatePtr from,
             xmlAutomataStatePtr to, const xmlChar *token,
             void *data) {
    xmlRegAtomPtr atom;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
        return(NULL);
    atom->data = data;
    if (atom == NULL)
    return(NULL);
    atom->valuep = xmlStrdup(token);

    if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
        xmlRegFreeAtom(atom);
    return(NULL);
    }
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewTransition2(xmlAutomataPtr am, xmlAutomataStatePtr from,
              xmlAutomataStatePtr to, const xmlChar *token,
              const xmlChar *token2, void *data) {
    xmlRegAtomPtr atom;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    atom->data = data;
    if ((token2 == NULL) || (*token2 == 0)) {
    atom->valuep = xmlStrdup(token);
    } else {
    int lenn, lenp;
    xmlChar *str;

    lenn = strlen((char *) token2);
    lenp = strlen((char *) token);

    str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
    if (str == NULL) {
        xmlRegFreeAtom(atom);
        return(NULL);
    }
    memcpy(&str[0], token, lenp);
    str[lenp] = '|';
    memcpy(&str[lenp + 1], token2, lenn);
    str[lenn + lenp + 1] = 0;

    atom->valuep = str;
    }

    if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
        xmlRegFreeAtom(atom);
    return(NULL);
    }
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewNegTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
               xmlAutomataStatePtr to, const xmlChar *token,
               const xmlChar *token2, void *data) {
    xmlRegAtomPtr atom;
    xmlChar err_msg[200];

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    atom->data = data;
    atom->neg = 1;
    if ((token2 == NULL) || (*token2 == 0)) {
    atom->valuep = xmlStrdup(token);
    } else {
    int lenn, lenp;
    xmlChar *str;

    lenn = strlen((char *) token2);
    lenp = strlen((char *) token);

    str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
    if (str == NULL) {
        xmlRegFreeAtom(atom);
        return(NULL);
    }
    memcpy(&str[0], token, lenp);
    str[lenp] = '|';
    memcpy(&str[lenp + 1], token2, lenn);
    str[lenn + lenp + 1] = 0;

    atom->valuep = str;
    }
    snprintf((char *) err_msg, 199, "not %s", (const char *) atom->valuep);
    err_msg[199] = 0;
    atom->valuep2 = xmlStrdup(err_msg);

    if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
        xmlRegFreeAtom(atom);
    return(NULL);
    }
    am->negs++;
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewCountTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from,
             xmlAutomataStatePtr to, const xmlChar *token,
             const xmlChar *token2,
             int min, int max, void *data) {
    xmlRegAtomPtr atom;
    int counter;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    if (min < 0)
    return(NULL);
    if ((max < min) || (max < 1))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    if ((token2 == NULL) || (*token2 == 0)) {
    atom->valuep = xmlStrdup(token);
    } else {
    int lenn, lenp;
    xmlChar *str;

    lenn = strlen((char *) token2);
    lenp = strlen((char *) token);

    str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
    if (str == NULL) {
        xmlRegFreeAtom(atom);
        return(NULL);
    }
    memcpy(&str[0], token, lenp);
    str[lenp] = '|';
    memcpy(&str[lenp + 1], token2, lenn);
    str[lenn + lenp + 1] = 0;

    atom->valuep = str;
    }
    atom->data = data;
    if (min == 0)
    atom->min = 1;
    else
    atom->min = min;
    atom->max = max;

    /*
     * associate a counter to the transition.
     */
    counter = xmlRegGetCounter(am);
    am->counters[counter].min = min;
    am->counters[counter].max = max;

    /* xmlFAGenerateTransitions(am, from, to, atom); */
    if (to == NULL) {
        to = xmlRegNewState(am);
    xmlRegStatePush(am, to);
    }
    xmlRegStateAddTrans(am, from, atom, to, counter, -1);
    xmlRegAtomPush(am, atom);
    am->state = to;

    if (to == NULL)
    to = am->state;
    if (to == NULL)
    return(NULL);
    if (min == 0)
    xmlFAGenerateEpsilonTransition(am, from, to);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewCountTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
             xmlAutomataStatePtr to, const xmlChar *token,
             int min, int max, void *data) {
    xmlRegAtomPtr atom;
    int counter;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    if (min < 0)
    return(NULL);
    if ((max < min) || (max < 1))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    atom->valuep = xmlStrdup(token);
    atom->data = data;
    if (min == 0)
    atom->min = 1;
    else
    atom->min = min;
    atom->max = max;

    /*
     * associate a counter to the transition.
     */
    counter = xmlRegGetCounter(am);
    am->counters[counter].min = min;
    am->counters[counter].max = max;

    /* xmlFAGenerateTransitions(am, from, to, atom); */
    if (to == NULL) {
        to = xmlRegNewState(am);
    xmlRegStatePush(am, to);
    }
    xmlRegStateAddTrans(am, from, atom, to, counter, -1);
    xmlRegAtomPush(am, atom);
    am->state = to;

    if (to == NULL)
    to = am->state;
    if (to == NULL)
    return(NULL);
    if (min == 0)
    xmlFAGenerateEpsilonTransition(am, from, to);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewOnceTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from,
             xmlAutomataStatePtr to, const xmlChar *token,
             const xmlChar *token2,
             int min, int max, void *data) {
    xmlRegAtomPtr atom;
    int counter;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    if (min < 1)
    return(NULL);
    if ((max < min) || (max < 1))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    if ((token2 == NULL) || (*token2 == 0)) {
    atom->valuep = xmlStrdup(token);
    } else {
    int lenn, lenp;
    xmlChar *str;

    lenn = strlen((char *) token2);
    lenp = strlen((char *) token);

    str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
    if (str == NULL) {
        xmlRegFreeAtom(atom);
        return(NULL);
    }
    memcpy(&str[0], token, lenp);
    str[lenp] = '|';
    memcpy(&str[lenp + 1], token2, lenn);
    str[lenn + lenp + 1] = 0;

    atom->valuep = str;
    }    
    atom->data = data;
    atom->quant = XML_REGEXP_QUANT_ONCEONLY;
    atom->min = min;
    atom->max = max;
    /*
     * associate a counter to the transition.
     */
    counter = xmlRegGetCounter(am);
    am->counters[counter].min = 1;
    am->counters[counter].max = 1;

    /* xmlFAGenerateTransitions(am, from, to, atom); */
    if (to == NULL) {
    to = xmlRegNewState(am);
    xmlRegStatePush(am, to);
    }
    xmlRegStateAddTrans(am, from, atom, to, counter, -1);
    xmlRegAtomPush(am, atom);
    am->state = to;
    return(to);
}

    

xmlAutomataStatePtr
xmlAutomataNewOnceTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
             xmlAutomataStatePtr to, const xmlChar *token,
             int min, int max, void *data) {
    xmlRegAtomPtr atom;
    int counter;

    if ((am == NULL) || (from == NULL) || (token == NULL))
    return(NULL);
    if (min < 1)
    return(NULL);
    if ((max < min) || (max < 1))
    return(NULL);
    atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
    if (atom == NULL)
    return(NULL);
    atom->valuep = xmlStrdup(token);
    atom->data = data;
    atom->quant = XML_REGEXP_QUANT_ONCEONLY;
    atom->min = min;
    atom->max = max;
    /*
     * associate a counter to the transition.
     */
    counter = xmlRegGetCounter(am);
    am->counters[counter].min = 1;
    am->counters[counter].max = 1;

    /* xmlFAGenerateTransitions(am, from, to, atom); */
    if (to == NULL) {
    to = xmlRegNewState(am);
    xmlRegStatePush(am, to);
    }
    xmlRegStateAddTrans(am, from, atom, to, counter, -1);
    xmlRegAtomPush(am, atom);
    am->state = to;
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewState(xmlAutomataPtr am) {
    xmlAutomataStatePtr to; 

    if (am == NULL)
    return(NULL);
    to = xmlRegNewState(am);
    xmlRegStatePush(am, to);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewEpsilon(xmlAutomataPtr am, xmlAutomataStatePtr from,
              xmlAutomataStatePtr to) {
    if ((am == NULL) || (from == NULL))
    return(NULL);
    xmlFAGenerateEpsilonTransition(am, from, to);
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewAllTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
               xmlAutomataStatePtr to, int lax) {
    if ((am == NULL) || (from == NULL))
    return(NULL);
    xmlFAGenerateAllTransition(am, from, to, lax);
    if (to == NULL)
    return(am->state);
    return(to);
}

int     
xmlAutomataNewCounter(xmlAutomataPtr am, int min, int max) {
    int ret;

    if (am == NULL)
    return(-1);

    ret = xmlRegGetCounter(am);
    if (ret < 0)
    return(-1);
    am->counters[ret].min = min;
    am->counters[ret].max = max;
    return(ret);
}

xmlAutomataStatePtr
xmlAutomataNewCountedTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
        xmlAutomataStatePtr to, int counter) {
    if ((am == NULL) || (from == NULL) || (counter < 0))
    return(NULL);
    xmlFAGenerateCountedEpsilonTransition(am, from, to, counter);
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlAutomataStatePtr
xmlAutomataNewCounterTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
        xmlAutomataStatePtr to, int counter) {
    if ((am == NULL) || (from == NULL) || (counter < 0))
    return(NULL);
    xmlFAGenerateCountedTransition(am, from, to, counter);
    if (to == NULL)
    return(am->state);
    return(to);
}

xmlRegexpPtr          
xmlAutomataCompile(xmlAutomataPtr am) {
    xmlRegexpPtr ret;

    if ((am == NULL) || (am->error != 0)) return(NULL);
    xmlFAEliminateEpsilonTransitions(am);
    /* xmlFAComputesDeterminism(am); */
    ret = xmlRegEpxFromParse(am);

    return(ret);
}

int          
xmlAutomataIsDeterminist(xmlAutomataPtr am) {
    int ret;

    if (am == NULL)
    return(-1);

    ret = xmlFAComputesDeterminism(am);
    return(ret);
}
#endif /* LIBXML_AUTOMATA_ENABLED */

#ifdef LIBXML_EXPR_ENABLED
/************************************************************************
 *                                  *
 *      Formal Expression handling code             *
 *                                  *
 ************************************************************************/
/************************************************************************
 *                                  *
 *      Expression handling context             *
 *                                  *
 ************************************************************************/

struct _xmlExpCtxt {
    xmlDictPtr dict;
    xmlExpNodePtr *table;
    int size;
    int nbElems;
    int nb_nodes;
    int maxNodes;
    const char *expr;
    const char *cur;
    int nb_cons;
    int tabSize;
};

xmlExpCtxtPtr
xmlExpNewCtxt(int maxNodes, xmlDictPtr dict) {
    xmlExpCtxtPtr ret;
    int size = 256;

    if (maxNodes <= 4096)
        maxNodes = 4096;
    
    ret = (xmlExpCtxtPtr) xmlMalloc(sizeof(xmlExpCtxt));
    if (ret == NULL)
        return(NULL);
    memset(ret, 0, sizeof(xmlExpCtxt));
    ret->size = size;
    ret->nbElems = 0;
    ret->maxNodes = maxNodes;
    ret->table = xmlMalloc(size * sizeof(xmlExpNodePtr));
    if (ret->table == NULL) {
        xmlFree(ret);
    return(NULL);
    }
    memset(ret->table, 0, size * sizeof(xmlExpNodePtr));
    if (dict == NULL) {
        ret->dict = xmlDictCreate();
    if (ret->dict == NULL) {
        xmlFree(ret->table);
        xmlFree(ret);
        return(NULL);
    }
    } else {
        ret->dict = dict;
    xmlDictReference(ret->dict);
    }
    return(ret);
}

void
xmlExpFreeCtxt(xmlExpCtxtPtr ctxt) {
    if (ctxt == NULL)
        return;
    xmlDictFree(ctxt->dict);
    if (ctxt->table != NULL)
    xmlFree(ctxt->table);
    xmlFree(ctxt);
}

/************************************************************************
 *                                  *
 *      Structure associated to an expression node      *
 *                                  *
 ************************************************************************/
#define MAX_NODES 10000

/* #define DEBUG_DERIV */

/*
 * TODO: 
 * - Wildcards
 * - public API for creation
 *
 * Started
 * - regression testing
 *
 * Done
 * - split into module and test tool
 * - memleaks
 */

typedef enum {
    XML_EXP_NILABLE = (1 << 0)
} xmlExpNodeInfo;

#define IS_NILLABLE(node) ((node)->info & XML_EXP_NILABLE)

struct _xmlExpNode {
    unsigned char type;/* xmlExpNodeType */
    unsigned char info;/* OR of xmlExpNodeInfo */
    unsigned short key; /* the hash key */
    unsigned int ref;   /* The number of references */
    int c_max;      /* the maximum length it can consume */
    xmlExpNodePtr exp_left;
    xmlExpNodePtr next;/* the next node in the hash table or free list */
    union {
    struct {
        int f_min;
        int f_max;
    } count;
    struct {
        xmlExpNodePtr f_right;
    } children;
        const xmlChar *f_str;
    } field;
};

#define exp_min field.count.f_min
#define exp_max field.count.f_max
/* #define exp_left field.children.f_left */
#define exp_right field.children.f_right
#define exp_str field.f_str

static xmlExpNodePtr xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type);
static xmlExpNode forbiddenExpNode = {
    XML_EXP_FORBID, 0, 0, 0, 0, NULL, NULL, {{ 0, 0}}
};
xmlExpNodePtr forbiddenExp = &forbiddenExpNode;
static xmlExpNode emptyExpNode = {
    XML_EXP_EMPTY, 1, 0, 0, 0, NULL, NULL, {{ 0, 0}}
};
xmlExpNodePtr emptyExp = &emptyExpNode;

/************************************************************************
 *                                  *
 *  The custom hash table for unicity and canonicalization      *
 *  of sub-expressions pointers                     *
 *                                  *
 ************************************************************************/
/*
 * xmlExpHashNameComputeKey:
 * Calculate the hash key for a token
 */
static unsigned short
xmlExpHashNameComputeKey(const xmlChar *name) {
    unsigned short value = 0L;
    char ch;
    
    if (name != NULL) {
    value += 30 * (*name);
    while ((ch = *name++) != 0) {
        value = value ^ ((value << 5) + (value >> 3) + (unsigned long)ch);
    }
    }
    return (value);
}

/*
 * xmlExpHashComputeKey:
 * Calculate the hash key for a compound expression
 */
static unsigned short
xmlExpHashComputeKey(xmlExpNodeType type, xmlExpNodePtr left,
                     xmlExpNodePtr right) {
    unsigned long value;
    unsigned short ret;
    
    switch (type) {
        case XML_EXP_SEQ:
        value = left->key;
        value += right->key;
        value *= 3;
        ret = (unsigned short) value;
        break;
        case XML_EXP_OR:
        value = left->key;
        value += right->key;
        value *= 7;
        ret = (unsigned short) value;
        break;
        case XML_EXP_COUNT:
        value = left->key;
        value += right->key;
        ret = (unsigned short) value;
        break;
    default:
        ret = 0;
    }
    return(ret);
}


static xmlExpNodePtr
xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type) {
    xmlExpNodePtr ret;

    if (ctxt->nb_nodes >= MAX_NODES)
        return(NULL);
    ret = (xmlExpNodePtr) xmlMalloc(sizeof(xmlExpNode));
    if (ret == NULL)
        return(NULL);
    memset(ret, 0, sizeof(xmlExpNode));
    ret->type = type;
    ret->next = NULL;
    ctxt->nb_nodes++;
    ctxt->nb_cons++;
    return(ret);
}

static xmlExpNodePtr
xmlExpHashGetEntry(xmlExpCtxtPtr ctxt, xmlExpNodeType type,
                   xmlExpNodePtr left, xmlExpNodePtr right,
           const xmlChar *name, int min, int max) {
    unsigned short kbase, key;
    xmlExpNodePtr entry;
    xmlExpNodePtr insert;

    if (ctxt == NULL)
    return(NULL);

    /*
     * Check for duplicate and insertion location.
     */
    if (type == XML_EXP_ATOM) {
    kbase = xmlExpHashNameComputeKey(name);
    } else if (type == XML_EXP_COUNT) {
        /* COUNT reduction rule 1 */
    /* a{1} -> a */
    if (min == max) {
        if (min == 1) {
        return(left);
        }
        if (min == 0) {
        xmlExpFree(ctxt, left);
            return(emptyExp);
        }
    }
    if (min < 0) {
        xmlExpFree(ctxt, left);
        return(forbiddenExp);
    }
        if (max == -1)
        kbase = min + 79;
    else
        kbase = max - min;
    kbase += left->key;
    } else if (type == XML_EXP_OR) {
        /* Forbid reduction rules */
        if (left->type == XML_EXP_FORBID) {
        xmlExpFree(ctxt, left);
        return(right);
    }
        if (right->type == XML_EXP_FORBID) {
        xmlExpFree(ctxt, right);
        return(left);
    }

        /* OR reduction rule 1 */
    /* a | a reduced to a */
        if (left == right) {
        left->ref--;
        return(left);
    }
        /* OR canonicalization rule 1 */
    /* linearize (a | b) | c into a | (b | c) */
        if ((left->type == XML_EXP_OR) && (right->type != XML_EXP_OR)) {
        xmlExpNodePtr tmp = left;
            left = right;
        right = tmp;
    }
        /* OR reduction rule 2 */
    /* a | (a | b) and b | (a | b) are reduced to a | b */
        if (right->type == XML_EXP_OR) {
        if ((left == right->exp_left) ||
            (left == right->exp_right)) {
        xmlExpFree(ctxt, left);
        return(right);
        }
    }
        /* OR canonicalization rule 2 */
    /* linearize (a | b) | c into a | (b | c) */
        if (left->type == XML_EXP_OR) {
        xmlExpNodePtr tmp;

        /* OR canonicalization rule 2 */
        if ((left->exp_right->type != XML_EXP_OR) &&
            (left->exp_right->key < left->exp_left->key)) {
            tmp = left->exp_right;
        left->exp_right = left->exp_left;
        left->exp_left = tmp;
        }
        left->exp_right->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_right, right,
                                 NULL, 0, 0);
        left->exp_left->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_left, tmp,
                                 NULL, 0, 0);
    
        xmlExpFree(ctxt, left);
        return(tmp);
    }
    if (right->type == XML_EXP_OR) {
        /* Ordering in the tree */
        /* C | (A | B) -> A | (B | C) */
        if (left->key > right->exp_right->key) {
        xmlExpNodePtr tmp;
        right->exp_right->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_right,
                                 left, NULL, 0, 0);
        right->exp_left->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left,
                                 tmp, NULL, 0, 0);
        xmlExpFree(ctxt, right);
        return(tmp);
        }
        /* Ordering in the tree */
        /* B | (A | C) -> A | (B | C) */
        if (left->key > right->exp_left->key) {
        xmlExpNodePtr tmp;
        right->exp_right->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left,
                                 right->exp_right, NULL, 0, 0);
        right->exp_left->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left,
                                 tmp, NULL, 0, 0);
        xmlExpFree(ctxt, right);
        return(tmp);
        }
    }
    /* we know both types are != XML_EXP_OR here */
        else if (left->key > right->key) {
        xmlExpNodePtr tmp = left;
            left = right;
        right = tmp;
    }
    kbase = xmlExpHashComputeKey(type, left, right);
    } else if (type == XML_EXP_SEQ) {
        /* Forbid reduction rules */
        if (left->type == XML_EXP_FORBID) {
        xmlExpFree(ctxt, right);
        return(left);
    }
        if (right->type == XML_EXP_FORBID) {
        xmlExpFree(ctxt, left);
        return(right);
    }
        /* Empty reduction rules */
        if (right->type == XML_EXP_EMPTY) {
        return(left);
    }
        if (left->type == XML_EXP_EMPTY) {
        return(right);
    }
    kbase = xmlExpHashComputeKey(type, left, right);
    } else 
        return(NULL);

    key = kbase % ctxt->size;
    if (ctxt->table[key] != NULL) {
    for (insert = ctxt->table[key]; insert != NULL;
         insert = insert->next) {
        if ((insert->key == kbase) &&
            (insert->type == type)) {
        if (type == XML_EXP_ATOM) {
            if (name == insert->exp_str) {
            insert->ref++;
            return(insert);
            }
        } else if (type == XML_EXP_COUNT) {
            if ((insert->exp_min == min) && (insert->exp_max == max) &&
                (insert->exp_left == left)) {
            insert->ref++;
            left->ref--;
            return(insert);
            }
        } else if ((insert->exp_left == left) &&
               (insert->exp_right == right)) {
            insert->ref++;
            left->ref--;
            right->ref--;
            return(insert);
        }
        }
    }
    }

    entry = xmlExpNewNode(ctxt, type);
    if (entry == NULL)
        return(NULL);
    entry->key = kbase;
    if (type == XML_EXP_ATOM) {
    entry->exp_str = name;
    entry->c_max = 1;
    } else if (type == XML_EXP_COUNT) {
        entry->exp_min = min;
        entry->exp_max = max;
    entry->exp_left = left;
    if ((min == 0) || (IS_NILLABLE(left)))
        entry->info |= XML_EXP_NILABLE;
    if (max < 0)
        entry->c_max = -1;
    else
        entry->c_max = max * entry->exp_left->c_max;
    } else {
    entry->exp_left = left;
    entry->exp_right = right;
    if (type == XML_EXP_OR) {
        if ((IS_NILLABLE(left)) || (IS_NILLABLE(right)))
        entry->info |= XML_EXP_NILABLE;
        if ((entry->exp_left->c_max == -1) ||
            (entry->exp_right->c_max == -1))
        entry->c_max = -1;
        else if (entry->exp_left->c_max > entry->exp_right->c_max)
            entry->c_max = entry->exp_left->c_max;
        else
            entry->c_max = entry->exp_right->c_max;
    } else {
        if ((IS_NILLABLE(left)) && (IS_NILLABLE(right)))
        entry->info |= XML_EXP_NILABLE;
        if ((entry->exp_left->c_max == -1) ||
            (entry->exp_right->c_max == -1))
        entry->c_max = -1;
        else
            entry->c_max = entry->exp_left->c_max + entry->exp_right->c_max;
    }
    }
    entry->ref = 1;
    if (ctxt->table[key] != NULL)
        entry->next = ctxt->table[key];

    ctxt->table[key] = entry;
    ctxt->nbElems++;

    return(entry);
}

void
xmlExpFree(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp) {
    if ((exp == NULL) || (exp == forbiddenExp) || (exp == emptyExp))
        return;
    exp->ref--;
    if (exp->ref == 0) {
        unsigned short key;

        /* Unlink it first from the hash table */
    key = exp->key % ctxt->size;
    if (ctxt->table[key] == exp) {
        ctxt->table[key] = exp->next;
    } else {
        xmlExpNodePtr tmp;

        tmp = ctxt->table[key];
        while (tmp != NULL) {
            if (tmp->next == exp) {
            tmp->next = exp->next;
            break;
        }
            tmp = tmp->next;
        }
    }

        if ((exp->type == XML_EXP_SEQ) || (exp->type == XML_EXP_OR)) {
        xmlExpFree(ctxt, exp->exp_left);
        xmlExpFree(ctxt, exp->exp_right);
    } else if (exp->type == XML_EXP_COUNT) {
        xmlExpFree(ctxt, exp->exp_left);
    }
        xmlFree(exp);
    ctxt->nb_nodes--;
    }
}

void
xmlExpRef(xmlExpNodePtr exp) {
    if (exp != NULL)
        exp->ref++;
}

xmlExpNodePtr
xmlExpNewAtom(xmlExpCtxtPtr ctxt, const xmlChar *name, int len) {
    if ((ctxt == NULL) || (name == NULL))
        return(NULL);
    name = xmlDictLookup(ctxt->dict, name, len);
    if (name == NULL)
        return(NULL);
    return(xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, name, 0, 0));
}

xmlExpNodePtr
xmlExpNewOr(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) {
    if (ctxt == NULL)
        return(NULL);
    if ((left == NULL) || (right == NULL)) {
        xmlExpFree(ctxt, left);
        xmlExpFree(ctxt, right);
        return(NULL);
    }
    return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, left, right, NULL, 0, 0));
}

xmlExpNodePtr
xmlExpNewSeq(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) {
    if (ctxt == NULL)
        return(NULL);
    if ((left == NULL) || (right == NULL)) {
        xmlExpFree(ctxt, left);
        xmlExpFree(ctxt, right);
        return(NULL);
    }
    return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, left, right, NULL, 0, 0));
}

xmlExpNodePtr
xmlExpNewRange(xmlExpCtxtPtr ctxt, xmlExpNodePtr subset, int min, int max) {
    if (ctxt == NULL)
        return(NULL);
    if ((subset == NULL) || (min < 0) || (max < -1) ||
        ((max >= 0) && (min > max))) {
    xmlExpFree(ctxt, subset);
        return(NULL);
    }
    return(xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, subset,
                              NULL, NULL, min, max));
}

/************************************************************************
 *                                  *
 *      Public API for operations on expressions        *
 *                                  *
 ************************************************************************/

static int
xmlExpGetLanguageInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, 
                     const xmlChar**list, int len, int nb) {
    int tmp, tmp2;
tail:
    switch (exp->type) {
        case XML_EXP_EMPTY:
        return(0);
        case XML_EXP_ATOM:
        for (tmp = 0;tmp < nb;tmp++)
            if (list[tmp] == exp->exp_str)
            return(0);
            if (nb >= len)
            return(-2);
        list[nb] = exp->exp_str;
        return(1);
        case XML_EXP_COUNT:
        exp = exp->exp_left;
        goto tail;
        case XML_EXP_SEQ:
        case XML_EXP_OR:
        tmp = xmlExpGetLanguageInt(ctxt, exp->exp_left, list, len, nb);
        if (tmp < 0)
            return(tmp);
        tmp2 = xmlExpGetLanguageInt(ctxt, exp->exp_right, list, len,
                                    nb + tmp);
        if (tmp2 < 0)
            return(tmp2);
            return(tmp + tmp2);
    }
    return(-1);
}

int
xmlExpGetLanguage(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, 
                  const xmlChar**langList, int len) {
    if ((ctxt == NULL) || (exp == NULL) || (langList == NULL) || (len <= 0))
        return(-1);
    return(xmlExpGetLanguageInt(ctxt, exp, langList, len, 0));
}

static int
xmlExpGetStartInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, 
                  const xmlChar**list, int len, int nb) {
    int tmp, tmp2;
tail:
    switch (exp->type) {
        case XML_EXP_FORBID:
        return(0);
        case XML_EXP_EMPTY:
        return(0);
        case XML_EXP_ATOM:
        for (tmp = 0;tmp < nb;tmp++)
            if (list[tmp] == exp->exp_str)
            return(0);
            if (nb >= len)
            return(-2);
        list[nb] = exp->exp_str;
        return(1);
        case XML_EXP_COUNT:
        exp = exp->exp_left;
        goto tail;
        case XML_EXP_SEQ:
        tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb);
        if (tmp < 0)
            return(tmp);
        if (IS_NILLABLE(exp->exp_left)) {
        tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len,
                        nb + tmp);
        if (tmp2 < 0)
            return(tmp2);
        tmp += tmp2;
        }
            return(tmp);
        case XML_EXP_OR:
        tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb);
        if (tmp < 0)
            return(tmp);
        tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len,
                                    nb + tmp);
        if (tmp2 < 0)
            return(tmp2);
            return(tmp + tmp2);
    }
    return(-1);
}

int
xmlExpGetStart(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, 
               const xmlChar**tokList, int len) {
    if ((ctxt == NULL) || (exp == NULL) || (tokList == NULL) || (len <= 0))
        return(-1);
    return(xmlExpGetStartInt(ctxt, exp, tokList, len, 0));
}

int
xmlExpIsNillable(xmlExpNodePtr exp) {
    if (exp == NULL)
        return(-1);
    return(IS_NILLABLE(exp) != 0);
}

static xmlExpNodePtr
xmlExpStringDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar *str)
{
    xmlExpNodePtr ret;

    switch (exp->type) {
    case XML_EXP_EMPTY:
        return(forbiddenExp);
    case XML_EXP_FORBID:
        return(forbiddenExp);
    case XML_EXP_ATOM:
        if (exp->exp_str == str) {
#ifdef DEBUG_DERIV
        printf("deriv atom: equal => Empty\n");
#endif
            ret = emptyExp;
        } else {
#ifdef DEBUG_DERIV
        printf("deriv atom: mismatch => forbid\n");
#endif
            /* TODO wildcards here */
        ret = forbiddenExp;
        }
        return(ret);
    case XML_EXP_OR: {
        xmlExpNodePtr tmp;

#ifdef DEBUG_DERIV
        printf("deriv or: => or(derivs)\n");
#endif
        tmp = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
        if (tmp == NULL) {
        return(NULL);
        }
        ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str);
        if (ret == NULL) {
            xmlExpFree(ctxt, tmp);
        return(NULL);
        }
            ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret,
                 NULL, 0, 0);
        return(ret);
    }
    case XML_EXP_SEQ:
#ifdef DEBUG_DERIV
        printf("deriv seq: starting with left\n");
#endif
        ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
        if (ret == NULL) {
            return(NULL);
        } else if (ret == forbiddenExp) {
            if (IS_NILLABLE(exp->exp_left)) {
#ifdef DEBUG_DERIV
            printf("deriv seq: left failed but nillable\n");
#endif
            ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str);
        }
        } else {
#ifdef DEBUG_DERIV
        printf("deriv seq: left match => sequence\n");
#endif
            exp->exp_right->ref++;
            ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, exp->exp_right,
                                 NULL, 0, 0);
        }
        return(ret);
    case XML_EXP_COUNT: {
        int min, max;
        xmlExpNodePtr tmp;

        if (exp->exp_max == 0)
        return(forbiddenExp);
        ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
        if (ret == NULL)
            return(NULL);
        if (ret == forbiddenExp) {
#ifdef DEBUG_DERIV
        printf("deriv count: pattern mismatch => forbid\n");
#endif
            return(ret);
        }
        if (exp->exp_max == 1)
        return(ret);
        if (exp->exp_max < 0) /* unbounded */
        max = -1;
        else
        max = exp->exp_max - 1;
        if (exp->exp_min > 0)
        min = exp->exp_min - 1;
        else
        min = 0;
        exp->exp_left->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left, NULL,
                     NULL, min, max);
        if (ret == emptyExp) {
#ifdef DEBUG_DERIV
        printf("deriv count: match to empty => new count\n");
#endif
            return(tmp);
        }
#ifdef DEBUG_DERIV
        printf("deriv count: match => sequence with new count\n");
#endif
        return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, tmp,
                                  NULL, 0, 0));
    }
    }
    return(NULL);
}

xmlExpNodePtr
xmlExpStringDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
                   const xmlChar *str, int len) {
    const xmlChar *input;

    if ((exp == NULL) || (ctxt == NULL) || (str == NULL)) {
        return(NULL);
    }
    /*
     * check the string is in the dictionnary, if yes use an interned
     * copy, otherwise we know it's not an acceptable input
     */
    input = xmlDictExists(ctxt->dict, str, len);
    if (input == NULL) {
        return(forbiddenExp);
    }
    return(xmlExpStringDeriveInt(ctxt, exp, input));
}

static int
xmlExpCheckCard(xmlExpNodePtr exp, xmlExpNodePtr sub) {
    int ret = 1;

    if (sub->c_max == -1) {
        if (exp->c_max != -1)
        ret = 0;
    } else if ((exp->c_max >= 0) && (exp->c_max < sub->c_max)) {
        ret = 0;
    }
#if 0
    if ((IS_NILLABLE(sub)) && (!IS_NILLABLE(exp)))
        ret = 0;
#endif
    return(ret);
}

static xmlExpNodePtr xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
                                        xmlExpNodePtr sub);
static int
xmlExpDivide(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub,
             xmlExpNodePtr *mult, xmlExpNodePtr *remain) {
    int i;
    xmlExpNodePtr tmp, tmp2;

    if (mult != NULL) *mult = NULL;
    if (remain != NULL) *remain = NULL;
    if (exp->c_max == -1) return(0);
    if (IS_NILLABLE(exp) && (!IS_NILLABLE(sub))) return(0);

    for (i = 1;i <= exp->c_max;i++) {
        sub->ref++;
        tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT,
                 sub, NULL, NULL, i, i);
    if (tmp == NULL) {
        return(-1);
    }
    if (!xmlExpCheckCard(tmp, exp)) {
        xmlExpFree(ctxt, tmp);
        continue;
    }
    tmp2 = xmlExpExpDeriveInt(ctxt, tmp, exp);
    if (tmp2 == NULL) {
        xmlExpFree(ctxt, tmp);
        return(-1);
    }
    if ((tmp2 != forbiddenExp) && (IS_NILLABLE(tmp2))) {
        if (remain != NULL)
            *remain = tmp2;
        else
            xmlExpFree(ctxt, tmp2);
        if (mult != NULL)
            *mult = tmp;
        else
            xmlExpFree(ctxt, tmp);
#ifdef DEBUG_DERIV
        printf("Divide succeeded %d\n", i);
#endif
        return(i);
    }
    xmlExpFree(ctxt, tmp);
    xmlExpFree(ctxt, tmp2);
    }
#ifdef DEBUG_DERIV
    printf("Divide failed\n");
#endif
    return(0);
}

static xmlExpNodePtr
xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
    xmlExpNodePtr ret, tmp, tmp2, tmp3;
    const xmlChar **tab;
    int len, i;

    /*
     * In case of equality and if the expression can only consume a finite
     * amount, then the derivation is empty
     */
    if ((exp == sub) && (exp->c_max >= 0)) {
#ifdef DEBUG_DERIV
        printf("Equal(exp, sub) and finite -> Empty\n");
#endif
        return(emptyExp);
    }
    /*
     * decompose sub sequence first
     */
    if (sub->type == XML_EXP_EMPTY) {
#ifdef DEBUG_DERIV
        printf("Empty(sub) -> Empty\n");
#endif
    exp->ref++;
        return(exp);
    }
    if (sub->type == XML_EXP_SEQ) {
#ifdef DEBUG_DERIV
        printf("Seq(sub) -> decompose\n");
#endif
        tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left);
    if (tmp == NULL)
        return(NULL);
    if (tmp == forbiddenExp)
        return(tmp);
    ret = xmlExpExpDeriveInt(ctxt, tmp, sub->exp_right);
    xmlExpFree(ctxt, tmp);
    return(ret);
    }
    if (sub->type == XML_EXP_OR) {
#ifdef DEBUG_DERIV
        printf("Or(sub) -> decompose\n");
#endif
        tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left);
    if (tmp == forbiddenExp)
        return(tmp);
    if (tmp == NULL)
        return(NULL);
    ret = xmlExpExpDeriveInt(ctxt, exp, sub->exp_right);
    if ((ret == NULL) || (ret == forbiddenExp)) {
        xmlExpFree(ctxt, tmp);
        return(ret);
    }
    return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret, NULL, 0, 0));
    }
    if (!xmlExpCheckCard(exp, sub)) {
#ifdef DEBUG_DERIV
        printf("CheckCard(exp, sub) failed -> Forbid\n");
#endif
        return(forbiddenExp);
    }
    switch (exp->type) {
        case XML_EXP_EMPTY:
        if (sub == emptyExp)
            return(emptyExp);
#ifdef DEBUG_DERIV
        printf("Empty(exp) -> Forbid\n");
#endif
        return(forbiddenExp);
        case XML_EXP_FORBID:
#ifdef DEBUG_DERIV
        printf("Forbid(exp) -> Forbid\n");
#endif
        return(forbiddenExp);
        case XML_EXP_ATOM:
        if (sub->type == XML_EXP_ATOM) {
            /* TODO: handle wildcards */
            if (exp->exp_str == sub->exp_str) {
#ifdef DEBUG_DERIV
            printf("Atom match -> Empty\n");
#endif
            return(emptyExp);
                }
#ifdef DEBUG_DERIV
        printf("Atom mismatch -> Forbid\n");
#endif
            return(forbiddenExp);
        }
        if ((sub->type == XML_EXP_COUNT) &&
            (sub->exp_max == 1) &&
            (sub->exp_left->type == XML_EXP_ATOM)) {
            /* TODO: handle wildcards */
            if (exp->exp_str == sub->exp_left->exp_str) {
#ifdef DEBUG_DERIV
            printf("Atom match -> Empty\n");
#endif
            return(emptyExp);
        }
#ifdef DEBUG_DERIV
        printf("Atom mismatch -> Forbid\n");
#endif
            return(forbiddenExp);
        }
#ifdef DEBUG_DERIV
        printf("Compex exp vs Atom -> Forbid\n");
#endif
        return(forbiddenExp);
        case XML_EXP_SEQ:
        /* try to get the sequence consumed only if possible */
        if (xmlExpCheckCard(exp->exp_left, sub)) {
        /* See if the sequence can be consumed directly */
#ifdef DEBUG_DERIV
        printf("Seq trying left only\n");
#endif
        ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
        if ((ret != forbiddenExp) && (ret != NULL)) {
#ifdef DEBUG_DERIV
            printf("Seq trying left only worked\n");
#endif
            /*
             * TODO: assumption here that we are determinist
             *       i.e. we won't get to a nillable exp left
             *       subset which could be matched by the right
             *       part too.
             * e.g.: (a | b)+,(a | c) and 'a+,a'
             */
            exp->exp_right->ref++;
            return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret,
                          exp->exp_right, NULL, 0, 0));
        }
#ifdef DEBUG_DERIV
        } else {
        printf("Seq: left too short\n");
#endif
        }
        /* Try instead to decompose */
        if (sub->type == XML_EXP_COUNT) {
        int min, max;

#ifdef DEBUG_DERIV
        printf("Seq: sub is a count\n");
#endif
            ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left);
        if (ret == NULL)
            return(NULL);
        if (ret != forbiddenExp) {
#ifdef DEBUG_DERIV
            printf("Seq , Count match on left\n");
#endif
            if (sub->exp_max < 0)
                max = -1;
                else
                max = sub->exp_max -1;
            if (sub->exp_min > 0)
                min = sub->exp_min -1;
            else
                min = 0;
            exp->exp_right->ref++;
            tmp = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret,
                                     exp->exp_right, NULL, 0, 0);
            if (tmp == NULL)
                return(NULL);

            sub->exp_left->ref++;
            tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT,
                      sub->exp_left, NULL, NULL, min, max);
            if (tmp2 == NULL) {
                xmlExpFree(ctxt, tmp);
            return(NULL);
            }
            ret = xmlExpExpDeriveInt(ctxt, tmp, tmp2);
            xmlExpFree(ctxt, tmp);
            xmlExpFree(ctxt, tmp2);
            return(ret);
        }
        }
        /* we made no progress on structured operations */
        break;
        case XML_EXP_OR:
#ifdef DEBUG_DERIV
        printf("Or , trying both side\n");
#endif
        ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
        if (ret == NULL)
            return(NULL);
        tmp = xmlExpExpDeriveInt(ctxt, exp->exp_right, sub);
        if (tmp == NULL) {
        xmlExpFree(ctxt, ret);
            return(NULL);
        }
        return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp, NULL, 0, 0));
        case XML_EXP_COUNT: {
        int min, max;

        if (sub->type == XML_EXP_COUNT) {
            /*
         * Try to see if the loop is completely subsumed
         */
            tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left);
        if (tmp == NULL)
            return(NULL);
        if (tmp == forbiddenExp) {
            int mult;

#ifdef DEBUG_DERIV
            printf("Count, Count inner don't subsume\n");
#endif
            mult = xmlExpDivide(ctxt, sub->exp_left, exp->exp_left,
                                NULL, &tmp);
            if (mult <= 0) {
#ifdef DEBUG_DERIV
            printf("Count, Count not multiple => forbidden\n");
#endif
                        return(forbiddenExp);
            }
            if (sub->exp_max == -1) {
                max = -1;
            if (exp->exp_max == -1) {
                if (exp->exp_min <= sub->exp_min * mult)
                    min = 0;
                else
                    min = exp->exp_min - sub->exp_min * mult;
            } else {
#ifdef DEBUG_DERIV
                printf("Count, Count finite can't subsume infinite\n");
#endif
                            xmlExpFree(ctxt, tmp);
                return(forbiddenExp);
            }
            } else {
            if (exp->exp_max == -1) {
#ifdef DEBUG_DERIV
                printf("Infinite loop consume mult finite loop\n");
#endif
                if (exp->exp_min > sub->exp_min * mult) {
                max = -1;
                min = exp->exp_min - sub->exp_min * mult;
                } else {
                max = -1;
                min = 0;
                }
            } else {
                if (exp->exp_max < sub->exp_max * mult) {
#ifdef DEBUG_DERIV
                printf("loops max mult mismatch => forbidden\n");
#endif
                xmlExpFree(ctxt, tmp);
                return(forbiddenExp);
                }
                if (sub->exp_max * mult > exp->exp_min)
                min = 0;
                else
                min = exp->exp_min - sub->exp_max * mult;
                max = exp->exp_max - sub->exp_max * mult;
            }
            }
        } else if (!IS_NILLABLE(tmp)) {
            /*
             * TODO: loop here to try to grow if working on finite
             *       blocks.
             */
#ifdef DEBUG_DERIV
            printf("Count, Count remain not nillable => forbidden\n");
#endif
            xmlExpFree(ctxt, tmp);
            return(forbiddenExp);
        } else if (sub->exp_max == -1) {
            if (exp->exp_max == -1) {
                if (exp->exp_min <= sub->exp_min) {
#ifdef DEBUG_DERIV
                printf("Infinite loops Okay => COUNT(0,Inf)\n");
#endif
                            max = -1;
                min = 0;
            } else {
#ifdef DEBUG_DERIV
                printf("Infinite loops min => Count(X,Inf)\n");
#endif
                            max = -1;
                min = exp->exp_min - sub->exp_min;
            }
            } else if (exp->exp_min > sub->exp_min) {
#ifdef DEBUG_DERIV
            printf("loops min mismatch 1 => forbidden ???\n");
#endif
                xmlExpFree(ctxt, tmp);
                return(forbiddenExp);
            } else {
            max = -1;
            min = 0;
            }
        } else {
            if (exp->exp_max == -1) {
#ifdef DEBUG_DERIV
            printf("Infinite loop consume finite loop\n");
#endif
                if (exp->exp_min > sub->exp_min) {
                max = -1;
                min = exp->exp_min - sub->exp_min;
            } else {
                max = -1;
                min = 0;
            }
            } else {
                if (exp->exp_max < sub->exp_max) {
#ifdef DEBUG_DERIV
                printf("loops max mismatch => forbidden\n");
#endif
                xmlExpFree(ctxt, tmp);
                return(forbiddenExp);
            }
            if (sub->exp_max > exp->exp_min)
                min = 0;
            else
                min = exp->exp_min - sub->exp_max;
            max = exp->exp_max - sub->exp_max;
            }
        }
#ifdef DEBUG_DERIV
        printf("loops match => SEQ(COUNT())\n");
#endif
        exp->exp_left->ref++;
        tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left,
                                  NULL, NULL, min, max);
        if (tmp2 == NULL) {
            return(NULL);
        }
                ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2,
                                 NULL, 0, 0);
        return(ret);
        }
        tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
        if (tmp == NULL)
        return(NULL);
        if (tmp == forbiddenExp) {
#ifdef DEBUG_DERIV
        printf("loop mismatch => forbidden\n");
#endif
        return(forbiddenExp);
        }
        if (exp->exp_min > 0)
        min = exp->exp_min - 1;
        else
        min = 0;
        if (exp->exp_max < 0)
        max = -1;
        else
        max = exp->exp_max - 1;

#ifdef DEBUG_DERIV
        printf("loop match => SEQ(COUNT())\n");
#endif
        exp->exp_left->ref++;
        tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left,
                      NULL, NULL, min, max);
        if (tmp2 == NULL)
        return(NULL);
        ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2,
                     NULL, 0, 0);
        return(ret);
    }
    }

#ifdef DEBUG_DERIV
    printf("Fallback to derivative\n");
#endif
    if (IS_NILLABLE(sub)) {
        if (!(IS_NILLABLE(exp)))
        return(forbiddenExp);
    else
        ret = emptyExp;
    } else
    ret = NULL;
    /*
     * here the structured derivation made no progress so
     * we use the default token based derivation to force one more step
     */
    if (ctxt->tabSize == 0)
        ctxt->tabSize = 40;

    tab = (const xmlChar **) xmlMalloc(ctxt->tabSize *
                                   sizeof(const xmlChar *));
    if (tab == NULL) {
    return(NULL);
    }

    /*
     * collect all the strings accepted by the subexpression on input
     */
    len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0);
    while (len < 0) {
        const xmlChar **temp;
    temp = (const xmlChar **) xmlRealloc((xmlChar **) tab, ctxt->tabSize * 2 *
                                         sizeof(const xmlChar *));
    if (temp == NULL) {
        xmlFree((xmlChar **) tab);
        return(NULL);
    }
    tab = temp;
    ctxt->tabSize *= 2;
    len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0);
    }
    for (i = 0;i < len;i++) {
        tmp = xmlExpStringDeriveInt(ctxt, exp, tab[i]);
    if ((tmp == NULL) || (tmp == forbiddenExp)) {
        xmlExpFree(ctxt, ret);
        xmlFree((xmlChar **) tab);
        return(tmp);
    }
    tmp2 = xmlExpStringDeriveInt(ctxt, sub, tab[i]);
    if ((tmp2 == NULL) || (tmp2 == forbiddenExp)) {
        xmlExpFree(ctxt, tmp);
        xmlExpFree(ctxt, ret);
        xmlFree((xmlChar **) tab);
        return(tmp);
    }
    tmp3 = xmlExpExpDeriveInt(ctxt, tmp, tmp2);
    xmlExpFree(ctxt, tmp);
    xmlExpFree(ctxt, tmp2);

    if ((tmp3 == NULL) || (tmp3 == forbiddenExp)) {
        xmlExpFree(ctxt, ret);
        xmlFree((xmlChar **) tab);
        return(tmp3);
    }

    if (ret == NULL)
        ret = tmp3;
    else {
        ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp3, NULL, 0, 0);
        if (ret == NULL) {
        xmlFree((xmlChar **) tab);
            return(NULL);
        }
    }
    }
    xmlFree((xmlChar **) tab);
    return(ret);
}
    
xmlExpNodePtr
xmlExpExpDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
    if ((exp == NULL) || (ctxt == NULL) || (sub == NULL))
        return(NULL);

    /*
     * O(1) speedups
     */
    if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) {
#ifdef DEBUG_DERIV
    printf("Sub nillable and not exp : can't subsume\n");
#endif
        return(forbiddenExp);
    }
    if (xmlExpCheckCard(exp, sub) == 0) {
#ifdef DEBUG_DERIV
    printf("sub generate longuer sequances than exp : can't subsume\n");
#endif
        return(forbiddenExp);
    }
    return(xmlExpExpDeriveInt(ctxt, exp, sub));
}

int
xmlExpSubsume(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
    xmlExpNodePtr tmp;
    
    if ((exp == NULL) || (ctxt == NULL) || (sub == NULL))
        return(-1);

    /*
     * TODO: speedup by checking the language of sub is a subset of the
     *       language of exp
     */
    /*
     * O(1) speedups
     */
    if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) {
#ifdef DEBUG_DERIV
    printf("Sub nillable and not exp : can't subsume\n");
#endif
        return(0);
    }
    if (xmlExpCheckCard(exp, sub) == 0) {
#ifdef DEBUG_DERIV
    printf("sub generate longuer sequances than exp : can't subsume\n");
#endif
        return(0);
    }
    tmp = xmlExpExpDeriveInt(ctxt, exp, sub);
#ifdef DEBUG_DERIV
    printf("Result derivation :\n");
    PRINT_EXP(tmp);
#endif
    if (tmp == NULL)
        return(-1);
    if (tmp == forbiddenExp)
    return(0);
    if (tmp == emptyExp)
    return(1);
    if ((tmp != NULL) && (IS_NILLABLE(tmp))) {
        xmlExpFree(ctxt, tmp);
        return(1);
    }
    xmlExpFree(ctxt, tmp);
    return(0);
}

/************************************************************************
 *                                  *
 *          Parsing expression              *
 *                                  *
 ************************************************************************/

static xmlExpNodePtr xmlExpParseExpr(xmlExpCtxtPtr ctxt);

#undef CUR
#define CUR (*ctxt->cur)
#undef NEXT
#define NEXT ctxt->cur++;
#undef IS_BLANK
#define IS_BLANK(c) ((c == ' ') || (c == '\n') || (c == '\r') || (c == '\t'))
#define SKIP_BLANKS while (IS_BLANK(*ctxt->cur)) ctxt->cur++;

static int
xmlExpParseNumber(xmlExpCtxtPtr ctxt) {
    int ret = 0;

    SKIP_BLANKS
    if (CUR == '*') {
    NEXT
    return(-1);
    }
    if ((CUR < '0') || (CUR > '9'))
        return(-1);
    while ((CUR >= '0') && (CUR <= '9')) {
        ret = ret * 10 + (CUR - '0');
    NEXT
    }
    return(ret);
}

static xmlExpNodePtr
xmlExpParseOr(xmlExpCtxtPtr ctxt) {
    const char *base;
    xmlExpNodePtr ret;
    const xmlChar *val;

    SKIP_BLANKS
    base = ctxt->cur;
    if (*ctxt->cur == '(') {
        NEXT
    ret = xmlExpParseExpr(ctxt);
    SKIP_BLANKS
    if (*ctxt->cur != ')') {
        fprintf(stderr, "unbalanced '(' : %s\n", base);
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
    NEXT;
    SKIP_BLANKS
    goto parse_quantifier;
    }
    while ((CUR != 0) && (!(IS_BLANK(CUR))) && (CUR != '(') &&
           (CUR != ')') && (CUR != '|') && (CUR != ',') && (CUR != '{') &&
       (CUR != '*') && (CUR != '+') && (CUR != '?') && (CUR != '}'))
    NEXT;
    val = xmlDictLookup(ctxt->dict, BAD_CAST base, ctxt->cur - base);
    if (val == NULL)
        return(NULL);
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, val, 0, 0);
    if (ret == NULL)
        return(NULL);
    SKIP_BLANKS
parse_quantifier:
    if (CUR == '{') {
        int min, max;

        NEXT
    min = xmlExpParseNumber(ctxt);
    if (min < 0) {
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
    SKIP_BLANKS
    if (CUR == ',') {
        NEXT
        max = xmlExpParseNumber(ctxt);
        SKIP_BLANKS
    } else
        max = min;
    if (CUR != '}') {
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
        NEXT
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
                             min, max);
    SKIP_BLANKS
    } else if (CUR == '?') {
        NEXT
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
                             0, 1);
    SKIP_BLANKS
    } else if (CUR == '+') {
        NEXT
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
                             1, -1);
    SKIP_BLANKS
    } else if (CUR == '*') {
        NEXT
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
                             0, -1);
    SKIP_BLANKS
    } 
    return(ret);
}


static xmlExpNodePtr
xmlExpParseSeq(xmlExpCtxtPtr ctxt) {
    xmlExpNodePtr ret, right;

    ret = xmlExpParseOr(ctxt);
    SKIP_BLANKS
    while (CUR == '|') {
        NEXT
    right = xmlExpParseOr(ctxt);
    if (right == NULL) {
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, right, NULL, 0, 0);
    if (ret == NULL)
        return(NULL);
    }
    return(ret);
}

static xmlExpNodePtr
xmlExpParseExpr(xmlExpCtxtPtr ctxt) {
    xmlExpNodePtr ret, right;

    ret = xmlExpParseSeq(ctxt);
    SKIP_BLANKS
    while (CUR == ',') {
        NEXT
    right = xmlExpParseSeq(ctxt);
    if (right == NULL) {
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
    ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, right, NULL, 0, 0);
    if (ret == NULL)
        return(NULL);
    }
    return(ret);
}

xmlExpNodePtr
xmlExpParse(xmlExpCtxtPtr ctxt, const char *expr) {
    xmlExpNodePtr ret;

    ctxt->expr = expr;
    ctxt->cur = expr;

    ret = xmlExpParseExpr(ctxt);
    SKIP_BLANKS
    if (*ctxt->cur != 0) {
        xmlExpFree(ctxt, ret);
        return(NULL);
    }
    return(ret);
}

static void
xmlExpDumpInt(xmlBufferPtr buf, xmlExpNodePtr expr, int glob) {
    xmlExpNodePtr c;

    if (expr == NULL) return;
    if (glob) xmlBufferWriteChar(buf, "(");
    switch (expr->type) {
        case XML_EXP_EMPTY:
        xmlBufferWriteChar(buf, "empty");
        break;
        case XML_EXP_FORBID:
        xmlBufferWriteChar(buf, "forbidden");
        break;
        case XML_EXP_ATOM:
        xmlBufferWriteCHAR(buf, expr->exp_str);
        break;
        case XML_EXP_SEQ:
        c = expr->exp_left;
        if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
            xmlExpDumpInt(buf, c, 1);
        else
            xmlExpDumpInt(buf, c, 0);
        xmlBufferWriteChar(buf, " , ");
        c = expr->exp_right;
        if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
            xmlExpDumpInt(buf, c, 1);
        else
            xmlExpDumpInt(buf, c, 0);
            break;
        case XML_EXP_OR:
        c = expr->exp_left;
        if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
            xmlExpDumpInt(buf, c, 1);
        else
            xmlExpDumpInt(buf, c, 0);
        xmlBufferWriteChar(buf, " | ");
        c = expr->exp_right;
        if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
            xmlExpDumpInt(buf, c, 1);
        else
            xmlExpDumpInt(buf, c, 0);
            break;
        case XML_EXP_COUNT: {
        char rep[40];
        
        c = expr->exp_left;
        if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
            xmlExpDumpInt(buf, c, 1);
        else
            xmlExpDumpInt(buf, c, 0);
        if ((expr->exp_min == 0) && (expr->exp_max == 1)) {
        rep[0] = '?';
        rep[1] = 0;
        } else if ((expr->exp_min == 0) && (expr->exp_max == -1)) {
        rep[0] = '*';
        rep[1] = 0;
        } else if ((expr->exp_min == 1) && (expr->exp_max == -1)) {
        rep[0] = '+';
        rep[1] = 0;
        } else if (expr->exp_max == expr->exp_min) {
            snprintf(rep, 39, "{%d}", expr->exp_min);
        } else if (expr->exp_max < 0) {
            snprintf(rep, 39, "{%d,inf}", expr->exp_min);
        } else {
            snprintf(rep, 39, "{%d,%d}", expr->exp_min, expr->exp_max);
        }
        rep[39] = 0;
        xmlBufferWriteChar(buf, rep);
        break;
    }
    default:
        fprintf(stderr, "Error in tree\n");
    }
    if (glob)
        xmlBufferWriteChar(buf, ")");
}
void
xmlExpDump(xmlBufferPtr buf, xmlExpNodePtr expr) {
    if ((buf == NULL) || (expr == NULL))
        return;
    xmlExpDumpInt(buf, expr, 0);
}

int
xmlExpMaxToken(xmlExpNodePtr expr) {
    if (expr == NULL)
        return(-1);
    return(expr->c_max);
}

int
xmlExpCtxtNbNodes(xmlExpCtxtPtr ctxt) {
    if (ctxt == NULL)
        return(-1);
    return(ctxt->nb_nodes);
}

int
xmlExpCtxtNbCons(xmlExpCtxtPtr ctxt) {
    if (ctxt == NULL)
        return(-1);
    return(ctxt->nb_cons);
}

#endif /* LIBXML_EXPR_ENABLED */
#define bottom_xmlregexp
#include "elfgcchack.h"
#endif /* LIBXML_REGEXP_ENABLED */