getopt.c

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#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <stdarg.h>
#include <stdio.h>

#define REPLACE_GETOPT

#define _DIAGASSERT(x) do {} while (0)

#ifdef REPLACE_GETOPT
#ifdef __weak_alias
__weak_alias(getopt,_getopt)
#endif
int opterr = 1;
int optind = 1;
int optopt = '?';
int optreset;
char *optarg;
#endif

#ifdef __weak_alias
__weak_alias(getopt_long,_getopt_long)
#endif

#ifndef __CYGWIN__
#define __progname __argv[0]
#else
extern char __declspec(dllimport) *__progname;
#endif

#define IGNORE_FIRST (*options == '-' || *options == '+')
#define PRINT_ERROR ((opterr) && ((*options != ':') || (IGNORE_FIRST && options[1] != ':')))

#ifndef IS_POSIXLY_CORRECT
#define IS_POSIXLY_CORRECT (getenv("POSIXLY_CORRECT") != NULL)
#endif

#define PERMUTE (!IS_POSIXLY_CORRECT && !IGNORE_FIRST)

#define IN_ORDER (!IS_POSIXLY_CORRECT && *options == '-')

#define BADCH (int)'?'
#define BADARG ((IGNORE_FIRST && options[1] == ':') || (*options == ':') ? (int)':' : (int)'?')
#define INORDER (int)1

static char EMSG[1];

static int getopt_internal (int,char * const *,const char *);
static int gcd (int,int);
static void permute_args (int,int,int,char * const *);

static char *place = EMSG;

static int nonopt_start = -1;
static int nonopt_end = -1;

static const char recargchar[] = "option requires an argument -- %c";
static const char recargstring[] = "option requires an argument -- %s";
static const char ambig[] = "ambiguous option -- %.*s";
static const char noarg[] = "option doesn't take an argument -- %.*s";
static const char illoptchar[] = "unknown option -- %c";
static const char illoptstring[] = "unknown option -- %s";

static void
_vwarnx(const char *fmt,va_list ap)
{
  (void)fprintf(stderr,"%s: ",__progname);
  if (fmt != NULL)
    (void)vfprintf(stderr,fmt,ap);
  (void)fprintf(stderr,"\n");
}

static void
warnx(const char *fmt,...)
{
  va_list ap;
  va_start(ap,fmt);
  _vwarnx(fmt,ap);
  va_end(ap);
}

static int
gcd(a,b)
    int a;
    int b;
{
    int c;

    c = a % b;
    while (c != 0) {
        a = b;
        b = c;
        c = a % b;
    }

    return b;
}

static void
permute_args(panonopt_start,panonopt_end,opt_end,nargv)
    int panonopt_start;
    int panonopt_end;
    int opt_end;
    char * const *nargv;
{
    int cstart,cyclelen,i,j,ncycle,nnonopts,nopts,pos;
    char *swap;

    _DIAGASSERT(nargv != NULL);

    nnonopts = panonopt_end - panonopt_start;
    nopts = opt_end - panonopt_end;
    ncycle = gcd(nnonopts,nopts);
    cyclelen = (opt_end - panonopt_start) / ncycle;

    for (i = 0; i < ncycle; i++) {
        cstart = panonopt_end+i;
        pos = cstart;
        for (j = 0; j < cyclelen; j++) {
            if (pos >= panonopt_end)
                pos -= nnonopts;
            else
                pos += nopts;
            swap = nargv[pos];

            ((char **) nargv)[pos] = nargv[cstart];

            ((char **)nargv)[cstart] = swap;
        }
    }
}

static int
getopt_internal(nargc,nargv,options)
    int nargc;
    char * const *nargv;
    const char *options;
{
    char *oli;
    int optchar;

    _DIAGASSERT(nargv != NULL);
    _DIAGASSERT(options != NULL);

    optarg = NULL;

    if (optind == 0)
        optind = 1;

    if (optreset)
        nonopt_start = nonopt_end = -1;
start:
    if (optreset || !*place) {
        optreset = 0;
        if (optind >= nargc) {
            place = EMSG;
            if (nonopt_end != -1) {

                permute_args(nonopt_start,nonopt_end,optind,nargv);
                optind -= nonopt_end - nonopt_start;
            }
            else if (nonopt_start != -1) {

                optind = nonopt_start;
            }
            nonopt_start = nonopt_end = -1;
            return -1;
        }
        if ((*(place = nargv[optind]) != '-')
            || (place[1] == '\0')) {
            place = EMSG;
            if (IN_ORDER) {

                optarg = nargv[optind++];
                return INORDER;
            }
            if (!PERMUTE) {

                return -1;
            }

            if (nonopt_start == -1)
                nonopt_start = optind;
            else if (nonopt_end != -1) {
                permute_args(nonopt_start,nonopt_end,optind,nargv);
                nonopt_start = optind -
                    (nonopt_end - nonopt_start);
                nonopt_end = -1;
            }
            optind++;

            goto start;
        }
        if (nonopt_start != -1 && nonopt_end == -1)
            nonopt_end = optind;
        if (place[1] && *++place == '-') {
            place++;
            return -2;
        }
    }
    if ((optchar = (int)*place++) == (int)':' ||
        (oli = strchr(options + (IGNORE_FIRST ? 1 : 0),optchar)) == NULL) {

        if (!*place)
            ++optind;
        if (PRINT_ERROR)
            warnx(illoptchar,optchar);
        optopt = optchar;
        return BADCH;
    }
    if (optchar == 'W' && oli[1] == ';') {

        if (*place)
            return -2;

        if (++optind >= nargc) {
            place = EMSG;
            if (PRINT_ERROR)
                warnx(recargchar,optchar);
            optopt = optchar;
            return BADARG;
        } else
            place = nargv[optind];

        return -2;
    }
    if (*++oli != ':') {
        if (!*place)
            ++optind;
    } else {
        optarg = NULL;
        if (*place)
            optarg = place;

        else if (oli[1] != ':') {
            if (++optind >= nargc) {
                place = EMSG;
                if (PRINT_ERROR)
                    warnx(recargchar,optchar);
                optopt = optchar;
                return BADARG;
            } else
                optarg = nargv[optind];
        }
        place = EMSG;
        ++optind;
    }

    return optchar;
}

#ifdef REPLACE_GETOPT

int
getopt(nargc,nargv,options)
    int nargc;
    char * const *nargv;
    const char *options;
{
    int retval;

    _DIAGASSERT(nargv != NULL);
    _DIAGASSERT(options != NULL);

    if ((retval = getopt_internal(nargc,nargv,options)) == -2) {
        ++optind;

        if (nonopt_end != -1) {
            permute_args(nonopt_start,nonopt_end,optind,nargv);
            optind -= nonopt_end - nonopt_start;
        }
        nonopt_start = nonopt_end = -1;
        retval = -1;
    }
    return retval;
}
#endif

int
getopt_long(nargc,nargv,options,long_options,idx)
    int nargc;
    char * const *nargv;
    const char *options;
    const struct option *long_options;
    int *idx;
{
    int retval;

    _DIAGASSERT(nargv != NULL);
    _DIAGASSERT(options != NULL);
    _DIAGASSERT(long_options != NULL);

    if ((retval = getopt_internal(nargc,nargv,options)) == -2) {
        char *current_argv,*has_equal;
        size_t current_argv_len;
        int i,match;

        current_argv = place;
        match = -1;

        optind++;
        place = EMSG;

        if (*current_argv == '\0') {

            if (nonopt_end != -1) {
                permute_args(nonopt_start,nonopt_end,optind,nargv);
                optind -= nonopt_end - nonopt_start;
            }
            nonopt_start = nonopt_end = -1;
            return -1;
        }
        if ((has_equal = strchr(current_argv,'=')) != NULL) {

            current_argv_len = has_equal - current_argv;
            has_equal++;
        } else
            current_argv_len = strlen(current_argv);

        for (i = 0; long_options[i].name; i++) {

            if (strncmp(current_argv,long_options[i].name,current_argv_len))
                continue;

            if (strlen(long_options[i].name) ==
                (unsigned)current_argv_len) {

                match = i;
                break;
            }
            if (match == -1)
                match = i;
            else {

                if (PRINT_ERROR)
                    warnx(ambig,(int)current_argv_len,current_argv);
                optopt = 0;
                return BADCH;
            }
        }
        if (match != -1) {
            if (long_options[match].has_arg == no_argument
                && has_equal) {
                if (PRINT_ERROR)
                    warnx(noarg,(int)current_argv_len,current_argv);

                if (long_options[match].flag == NULL)
                    optopt = long_options[match].val;
                else
                    optopt = 0;
                return BADARG;
            }
            if (long_options[match].has_arg == required_argument ||
                long_options[match].has_arg == optional_argument) {
                if (has_equal)
                    optarg = has_equal;
                else if (long_options[match].has_arg ==
                    required_argument) {

                    optarg = nargv[optind++];
                }
            }
            if ((long_options[match].has_arg == required_argument)
                && (optarg == NULL)) {

                if (PRINT_ERROR)
                    warnx(recargstring,current_argv);

                if (long_options[match].flag == NULL)
                    optopt = long_options[match].val;
                else
                    optopt = 0;
                --optind;
                return BADARG;
            }
        } else {
            if (PRINT_ERROR)
                warnx(illoptstring,current_argv);
            optopt = 0;
            return BADCH;
        }
        if (long_options[match].flag) {
            *long_options[match].flag = long_options[match].val;
            retval = 0;
        } else
            retval = long_options[match].val;
        if (idx)
            *idx = match;
    }
    return retval;
}