gnulib/lib/unicodeio.c - toolchain/make - Git at Google

 /* Unicode character output to streams with locale dependent encoding.

    Copyright (C) 2000-2003, 2006, 2008-2020 Free Software Foundation, Inc.

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

 /* Written by Bruno Haible <haible@clisp.cons.org>.  */

 #include <config.h>

 /* Specification.  */
 #include "unicodeio.h"

 #include <stdio.h>
 #include <string.h>
 #include <errno.h>

 #if HAVE_ICONV
 # include <iconv.h>
 #endif

 #include <error.h>

 #include "gettext.h"
 #define _(msgid) gettext (msgid)
 #define N_(msgid) msgid

 #include "localcharset.h"
 #include "unistr.h"

 /* When we pass a Unicode character to iconv(), we must pass it in a
    suitable encoding. The standardized Unicode encodings are
    UTF-8, UCS-2, UCS-4, UTF-16, UTF-16BE, UTF-16LE, UTF-7.
    UCS-2 supports only characters up to \U0000FFFF.
    UTF-16 and variants support only characters up to \U0010FFFF.
    UTF-7 is way too complex and not supported by glibc-2.1.
    UCS-4 specification leaves doubts about endianness and byte order
    mark. glibc currently interprets it as big endian without byte order
    mark, but this is not backed by an RFC.
    So we use UTF-8. It supports characters up to \U7FFFFFFF and is
    unambiguously defined.  */

 /* Luckily, the encoding's name is platform independent.  */
 #define UTF8_NAME "UTF-8"

 /* Converts the Unicode character CODE to its multibyte representation
    in the current locale and calls the SUCCESS callback on the resulting
    byte sequence.  If an error occurs, invokes the FAILURE callback instead,
    passing it CODE and an English error string.
    Returns whatever the callback returned.
    Assumes that the locale doesn't change between two calls.  */
 long
 unicode_to_mb (unsigned int code,
                long (*success) (const char *buf, size_t buflen,
                                 void *callback_arg),
                long (*failure) (unsigned int code, const char *msg,
                                 void *callback_arg),
                void *callback_arg)
 {
   static int initialized;
   static int is_utf8;
 #if HAVE_ICONV
   static iconv_t utf8_to_local;
 #endif

   char inbuf[6];
   int count;

   if (!initialized)
     {
       const char *charset = locale_charset ();

       is_utf8 = !strcmp (charset, UTF8_NAME);
 #if HAVE_ICONV
       if (!is_utf8)
         {
           utf8_to_local = iconv_open (charset, UTF8_NAME);
           if (utf8_to_local == (iconv_t)(-1))
             /* For an unknown encoding, assume ASCII.  */
             utf8_to_local = iconv_open ("ASCII", UTF8_NAME);
         }
 #endif
       initialized = 1;
     }

   /* Test whether the utf8_to_local converter is available at all.  */
   if (!is_utf8)
     {
 #if HAVE_ICONV
       if (utf8_to_local == (iconv_t)(-1))
         return failure (code, N_("iconv function not usable"), callback_arg);
 #else
       return failure (code, N_("iconv function not available"), callback_arg);
 #endif
     }

   /* Convert the character to UTF-8.  */
   count = u8_uctomb ((unsigned char *) inbuf, code, sizeof (inbuf));
   if (count < 0)
     return failure (code, N_("character out of range"), callback_arg);

 #if HAVE_ICONV
   if (!is_utf8)
     {
       char outbuf[25];
       const char *inptr;
       size_t inbytesleft;
       char *outptr;
       size_t outbytesleft;
       size_t res;

       inptr = inbuf;
       inbytesleft = count;
       outptr = outbuf;
       outbytesleft = sizeof (outbuf);

       /* Convert the character from UTF-8 to the locale's charset.  */
       res = iconv (utf8_to_local,
                    (ICONV_CONST char **)&inptr, &inbytesleft,
                    &outptr, &outbytesleft);
       if (inbytesleft > 0 || res == (size_t)(-1)
           /* Irix iconv() inserts a NUL byte if it cannot convert. */
 # if !defined _LIBICONV_VERSION && (defined sgi || defined __sgi)
           || (res > 0 && code != 0 && outptr - outbuf == 1 && *outbuf == '\0')
 # endif
          )
         return failure (code, NULL, callback_arg);

       /* Avoid glibc-2.1 bug and Solaris 7 bug.  */
 # if defined _LIBICONV_VERSION \
     || !(((__GLIBC__ - 0 == 2 && __GLIBC_MINOR__ - 0 <= 1) \
           && !defined __UCLIBC__) \
          || defined __sun)

       /* Get back to the initial shift state.  */
       res = iconv (utf8_to_local, NULL, NULL, &outptr, &outbytesleft);
       if (res == (size_t)(-1))
         return failure (code, NULL, callback_arg);
 # endif

       return success (outbuf, outptr - outbuf, callback_arg);
     }
 #endif

   /* At this point, is_utf8 is true, so no conversion is needed.  */
   return success (inbuf, count, callback_arg);
 }

 /* Simple success callback that outputs the converted string.
    The STREAM is passed as callback_arg.  */
 long
 fwrite_success_callback (const char *buf, size_t buflen, void *callback_arg)
 {
   FILE *stream = (FILE *) callback_arg;

   /* The return value of fwrite can be ignored here, because under normal
      conditions (STREAM is an open stream and not wide-character oriented)
      when fwrite() returns a value != buflen it also sets STREAM's error
      indicator.  */
   fwrite (buf, 1, buflen, stream);
   return 0;
 }

 /* Simple failure callback that displays an error and exits.  */
 static long
 exit_failure_callback (unsigned int code, const char *msg,
                        void *callback_arg _GL_UNUSED)
 {
   if (msg == NULL)
     error (1, 0, _("cannot convert U+%04X to local character set"), code);
   else
     error (1, 0, _("cannot convert U+%04X to local character set: %s"), code,
            gettext (msg));
   return -1;
 }

 /* Simple failure callback that displays a fallback representation in plain
    ASCII, using the same notation as ISO C99 strings.  */
 static long
 fallback_failure_callback (unsigned int code,
                            const char *msg _GL_UNUSED,
                            void *callback_arg)
 {
   FILE *stream = (FILE *) callback_arg;

   if (code < 0x10000)
     fprintf (stream, "\\u%04X", code);
   else
     fprintf (stream, "\\U%08X", code);
   return -1;
 }

 /* Outputs the Unicode character CODE to the output stream STREAM.
    Upon failure, exit if exit_on_error is true, otherwise output a fallback
    notation.  */
 void
 print_unicode_char (FILE *stream, unsigned int code, int exit_on_error)
 {
   unicode_to_mb (code, fwrite_success_callback,
                  exit_on_error
                  ? exit_failure_callback
                  : fallback_failure_callback,
                  stream);
 }
	/* Unicode character output to streams with locale dependent encoding.

	Copyright (C) 2000-2003, 2006, 2008-2020 Free Software Foundation, Inc.

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program. If not, see <https://www.gnu.org/licenses/>. */

	/* Written by Bruno Haible <haible@clisp.cons.org>. */

	#include <config.h>

	/* Specification. */
	#include "unicodeio.h"

	#include <stdio.h>
	#include <string.h>
	#include <errno.h>

	#if HAVE_ICONV
	# include <iconv.h>
	#endif

	#include <error.h>

	#include "gettext.h"
	#define _(msgid) gettext (msgid)
	#define N_(msgid) msgid

	#include "localcharset.h"
	#include "unistr.h"

	/* When we pass a Unicode character to iconv(), we must pass it in a
	suitable encoding. The standardized Unicode encodings are
	UTF-8, UCS-2, UCS-4, UTF-16, UTF-16BE, UTF-16LE, UTF-7.
	UCS-2 supports only characters up to \U0000FFFF.
	UTF-16 and variants support only characters up to \U0010FFFF.
	UTF-7 is way too complex and not supported by glibc-2.1.
	UCS-4 specification leaves doubts about endianness and byte order
	mark. glibc currently interprets it as big endian without byte order
	mark, but this is not backed by an RFC.
	So we use UTF-8. It supports characters up to \U7FFFFFFF and is
	unambiguously defined. */

	/* Luckily, the encoding's name is platform independent. */
	#define UTF8_NAME "UTF-8"

	/* Converts the Unicode character CODE to its multibyte representation
	in the current locale and calls the SUCCESS callback on the resulting
	byte sequence. If an error occurs, invokes the FAILURE callback instead,
	passing it CODE and an English error string.
	Returns whatever the callback returned.
	Assumes that the locale doesn't change between two calls. */
	long
	unicode_to_mb (unsigned int code,
	long (success) (const char buf, size_t buflen,
	void *callback_arg),
	long (failure) (unsigned int code, const char msg,
	void *callback_arg),
	void *callback_arg)
	{
	static int initialized;
	static int is_utf8;
	#if HAVE_ICONV
	static iconv_t utf8_to_local;
	#endif

	char inbuf[6];
	int count;

	if (!initialized)
	{
	const char *charset = locale_charset ();

	is_utf8 = !strcmp (charset, UTF8_NAME);
	#if HAVE_ICONV
	if (!is_utf8)
	{
	utf8_to_local = iconv_open (charset, UTF8_NAME);
	if (utf8_to_local == (iconv_t)(-1))
	/* For an unknown encoding, assume ASCII. */
	utf8_to_local = iconv_open ("ASCII", UTF8_NAME);
	}
	#endif
	initialized = 1;
	}

	/* Test whether the utf8_to_local converter is available at all. */
	if (!is_utf8)
	{
	#if HAVE_ICONV
	if (utf8_to_local == (iconv_t)(-1))
	return failure (code, N_("iconv function not usable"), callback_arg);
	#else
	return failure (code, N_("iconv function not available"), callback_arg);
	#endif
	}

	/* Convert the character to UTF-8. */
	count = u8_uctomb ((unsigned char *) inbuf, code, sizeof (inbuf));
	if (count < 0)
	return failure (code, N_("character out of range"), callback_arg);

	#if HAVE_ICONV
	if (!is_utf8)
	{
	char outbuf[25];
	const char *inptr;
	size_t inbytesleft;
	char *outptr;
	size_t outbytesleft;
	size_t res;

	inptr = inbuf;
	inbytesleft = count;
	outptr = outbuf;
	outbytesleft = sizeof (outbuf);

	/* Convert the character from UTF-8 to the locale's charset. */
	res = iconv (utf8_to_local,
	(ICONV_CONST char **)&inptr, &inbytesleft,
	&outptr, &outbytesleft);
	if (inbytesleft > 0 \|\| res == (size_t)(-1)
	/* Irix iconv() inserts a NUL byte if it cannot convert. */
	# if !defined _LIBICONV_VERSION && (defined sgi \|\| defined __sgi)
	\|\| (res > 0 && code != 0 && outptr - outbuf == 1 && *outbuf == '\0')
	# endif
	)
	return failure (code, NULL, callback_arg);

	/* Avoid glibc-2.1 bug and Solaris 7 bug. */
	# if defined _LIBICONV_VERSION \
	\|\| !(((__GLIBC__ - 0 == 2 && __GLIBC_MINOR__ - 0 <= 1) \
	&& !defined __UCLIBC__) \
	\|\| defined __sun)

	/* Get back to the initial shift state. */
	res = iconv (utf8_to_local, NULL, NULL, &outptr, &outbytesleft);
	if (res == (size_t)(-1))
	return failure (code, NULL, callback_arg);
	# endif

	return success (outbuf, outptr - outbuf, callback_arg);
	}
	#endif

	/* At this point, is_utf8 is true, so no conversion is needed. */
	return success (inbuf, count, callback_arg);
	}

	/* Simple success callback that outputs the converted string.
	The STREAM is passed as callback_arg. */
	long
	fwrite_success_callback (const char buf, size_t buflen, void callback_arg)
	{
	FILE stream = (FILE ) callback_arg;

	/* The return value of fwrite can be ignored here, because under normal
	conditions (STREAM is an open stream and not wide-character oriented)
	when fwrite() returns a value != buflen it also sets STREAM's error
	indicator. */
	fwrite (buf, 1, buflen, stream);
	return 0;
	}

	/* Simple failure callback that displays an error and exits. */
	static long
	exit_failure_callback (unsigned int code, const char *msg,
	void *callback_arg _GL_UNUSED)
	{
	if (msg == NULL)
	error (1, 0, _("cannot convert U+%04X to local character set"), code);
	else
	error (1, 0, _("cannot convert U+%04X to local character set: %s"), code,
	gettext (msg));
	return -1;
	}

	/* Simple failure callback that displays a fallback representation in plain
	ASCII, using the same notation as ISO C99 strings. */
	static long
	fallback_failure_callback (unsigned int code,
	const char *msg _GL_UNUSED,
	void *callback_arg)
	{
	FILE stream = (FILE ) callback_arg;

	if (code < 0x10000)
	fprintf (stream, "\\u%04X", code);
	else
	fprintf (stream, "\\U%08X", code);
	return -1;
	}

	/* Outputs the Unicode character CODE to the output stream STREAM.
	Upon failure, exit if exit_on_error is true, otherwise output a fallback
	notation. */
	void
	print_unicode_char (FILE *stream, unsigned int code, int exit_on_error)
	{
	unicode_to_mb (code, fwrite_success_callback,
	exit_on_error
	? exit_failure_callback
	: fallback_failure_callback,
	stream);
	}