encoding.h

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/*
 * Summary: interface for the encoding conversion functions
 * Description: interface for the encoding conversion functions needed for
 *              XML basic encoding and iconv() support.
 *
 * Related specs are
 * rfc2044        (UTF-8 and UTF-16) F. Yergeau Alis Technologies
 * [ISO-10646]    UTF-8 and UTF-16 in Annexes
 * [ISO-8859-1]   ISO Latin-1 characters codes.
 * [UNICODE]      The Unicode Consortium, "The Unicode Standard --
 *                Worldwide Character Encoding -- Version 1.0", Addison-
 *                Wesley, Volume 1, 1991, Volume 2, 1992.  UTF-8 is
 *                described in Unicode Technical Report #4.
 * [US-ASCII]     Coded Character Set--7-bit American Standard Code for
 *                Information Interchange, ANSI X3.4-1986.
 *
 * Copy: See Copyright for the status of this software.
 *
 * Author: Daniel Veillard
 */

#ifndef __XML_CHAR_ENCODING_H__
#define __XML_CHAR_ENCODING_H__

#include <libxml/xmlversion.h>

#ifdef LIBXML_ICONV_ENABLED
#include <iconv.h>
#endif
#ifdef LIBXML_ICU_ENABLED
#include <unicode/ucnv.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif

/*
 * xmlCharEncoding:
 *
 * Predefined values for some standard encodings.
 * Libxml does not do beforehand translation on UTF8 and ISOLatinX.
 * It also supports ASCII, ISO-8859-1, and UTF16 (LE and BE) by default.
 *
 * Anything else would have to be translated to UTF8 before being
 * given to the parser itself. The BOM for UTF16 and the encoding
 * declaration are looked at and a converter is looked for at that
 * point. If not found the parser stops here as asked by the XML REC. A
 * converter can be registered by the user using xmlRegisterCharEncodingHandler
 * but the current form doesn't allow stateful transcoding (a serious
 * problem agreed !). If iconv has been found it will be used
 * automatically and allow stateful transcoding, the simplest is then
 * to be sure to enable iconv and to provide iconv libs for the encoding
 * support needed.
 *
 * Note that the generic "UTF-16" is not a predefined value.  Instead, only
 * the specific UTF-16LE and UTF-16BE are present.
 */
typedef enum {
    XML_CHAR_ENCODING_ERROR=   -1, /* No char encoding detected */
    XML_CHAR_ENCODING_NONE= 0, /* No char encoding detected */
    XML_CHAR_ENCODING_UTF8= 1, /* UTF-8 */
    XML_CHAR_ENCODING_UTF16LE=  2, /* UTF-16 little endian */
    XML_CHAR_ENCODING_UTF16BE=  3, /* UTF-16 big endian */
    XML_CHAR_ENCODING_UCS4LE=   4, /* UCS-4 little endian */
    XML_CHAR_ENCODING_UCS4BE=   5, /* UCS-4 big endian */
    XML_CHAR_ENCODING_EBCDIC=   6, /* EBCDIC uh! */
    XML_CHAR_ENCODING_UCS4_2143=7, /* UCS-4 unusual ordering */
    XML_CHAR_ENCODING_UCS4_3412=8, /* UCS-4 unusual ordering */
    XML_CHAR_ENCODING_UCS2= 9, /* UCS-2 */
    XML_CHAR_ENCODING_8859_1=   10,/* ISO-8859-1 ISO Latin 1 */
    XML_CHAR_ENCODING_8859_2=   11,/* ISO-8859-2 ISO Latin 2 */
    XML_CHAR_ENCODING_8859_3=   12,/* ISO-8859-3 */
    XML_CHAR_ENCODING_8859_4=   13,/* ISO-8859-4 */
    XML_CHAR_ENCODING_8859_5=   14,/* ISO-8859-5 */
    XML_CHAR_ENCODING_8859_6=   15,/* ISO-8859-6 */
    XML_CHAR_ENCODING_8859_7=   16,/* ISO-8859-7 */
    XML_CHAR_ENCODING_8859_8=   17,/* ISO-8859-8 */
    XML_CHAR_ENCODING_8859_9=   18,/* ISO-8859-9 */
    XML_CHAR_ENCODING_2022_JP=  19,/* ISO-2022-JP */
    XML_CHAR_ENCODING_SHIFT_JIS=20,/* Shift_JIS */
    XML_CHAR_ENCODING_EUC_JP=   21,/* EUC-JP */
    XML_CHAR_ENCODING_ASCII=    22 /* pure ASCII */
} xmlCharEncoding;

typedef int (* xmlCharEncodingInputFunc)(unsigned char *out, int *outlen,
                                         const unsigned char *in, int *inlen);


typedef int (* xmlCharEncodingOutputFunc)(unsigned char *out, int *outlen,
                                          const unsigned char *in, int *inlen);


/*
 * Block defining the handlers for non UTF-8 encodings.
 * If iconv is supported, there are two extra fields.
 */
#ifdef LIBXML_ICU_ENABLED
/* Size of pivot buffer, same as icu/source/common/ucnv.cpp CHUNK_SIZE */
#define ICU_PIVOT_BUF_SIZE 1024
struct _uconv_t {
  UConverter *uconv; /* for conversion between an encoding and UTF-16 */
  UConverter *utf8; /* for conversion between UTF-8 and UTF-16 */
  UChar      pivot_buf[ICU_PIVOT_BUF_SIZE];
  UChar      *pivot_source;
  UChar      *pivot_target;
};
typedef struct _uconv_t uconv_t;
#endif

typedef struct _xmlCharEncodingHandler xmlCharEncodingHandler;
typedef xmlCharEncodingHandler *xmlCharEncodingHandlerPtr;
struct _xmlCharEncodingHandler {
    char                       *name;
    xmlCharEncodingInputFunc   input;
    xmlCharEncodingOutputFunc  output;
#ifdef LIBXML_ICONV_ENABLED
    iconv_t                    iconv_in;
    iconv_t                    iconv_out;
#endif /* LIBXML_ICONV_ENABLED */
#ifdef LIBXML_ICU_ENABLED
    uconv_t                    *uconv_in;
    uconv_t                    *uconv_out;
#endif /* LIBXML_ICU_ENABLED */
};

#ifdef __cplusplus
}
#endif
#include <libxml/tree.h>
#ifdef __cplusplus
extern "C" {
#endif

/*
 * Interfaces for encoding handlers.
 */
XMLPUBFUN void XMLCALL
    xmlInitCharEncodingHandlers (void);
XMLPUBFUN void XMLCALL
    xmlCleanupCharEncodingHandlers  (void);
XMLPUBFUN void XMLCALL
    xmlRegisterCharEncodingHandler  (xmlCharEncodingHandlerPtr handler);
XMLPUBFUN xmlCharEncodingHandlerPtr XMLCALL
    xmlGetCharEncodingHandler   (xmlCharEncoding enc);
XMLPUBFUN xmlCharEncodingHandlerPtr XMLCALL
    xmlFindCharEncodingHandler  (const char *name);
XMLPUBFUN xmlCharEncodingHandlerPtr XMLCALL
    xmlNewCharEncodingHandler   (const char *name,
                     xmlCharEncodingInputFunc input,
                     xmlCharEncodingOutputFunc output);

/*
 * Interfaces for encoding names and aliases.
 */
XMLPUBFUN int XMLCALL
    xmlAddEncodingAlias     (const char *name,
                     const char *alias);
XMLPUBFUN int XMLCALL
    xmlDelEncodingAlias     (const char *alias);
XMLPUBFUN const char * XMLCALL
    xmlGetEncodingAlias     (const char *alias);
XMLPUBFUN void XMLCALL
    xmlCleanupEncodingAliases   (void);
XMLPUBFUN xmlCharEncoding XMLCALL
    xmlParseCharEncoding        (const char *name);
XMLPUBFUN const char * XMLCALL
    xmlGetCharEncodingName      (xmlCharEncoding enc);

/*
 * Interfaces directly used by the parsers.
 */
XMLPUBFUN xmlCharEncoding XMLCALL
    xmlDetectCharEncoding       (const unsigned char *in,
                     int len);

XMLPUBFUN int XMLCALL
    xmlCharEncOutFunc       (xmlCharEncodingHandler *handler,
                     xmlBufferPtr out,
                     xmlBufferPtr in);

XMLPUBFUN int XMLCALL
    xmlCharEncInFunc        (xmlCharEncodingHandler *handler,
                     xmlBufferPtr out,
                     xmlBufferPtr in);
XMLPUBFUN int XMLCALL
    xmlCharEncFirstLine     (xmlCharEncodingHandler *handler,
                     xmlBufferPtr out,
                     xmlBufferPtr in);
XMLPUBFUN int XMLCALL
    xmlCharEncCloseFunc     (xmlCharEncodingHandler *handler);

/*
 * Export a few useful functions
 */
#ifdef LIBXML_OUTPUT_ENABLED
XMLPUBFUN int XMLCALL
    UTF8Toisolat1           (unsigned char *out,
                     int *outlen,
                     const unsigned char *in,
                     int *inlen);
#endif /* LIBXML_OUTPUT_ENABLED */
XMLPUBFUN int XMLCALL
    isolat1ToUTF8           (unsigned char *out,
                     int *outlen,
                     const unsigned char *in,
                     int *inlen);
#ifdef __cplusplus
}
#endif

#endif /* __XML_CHAR_ENCODING_H__ */