lib/charconv.c

   1 /* Dia -- an diagram creation/manipulation program
   2  * Copyright (C) 1998 Alexander Larsson
   3  *
   4  * charconv.c: simple wrapper around unicode_iconv until we get dia to use
   5  * utf8 internally.
   6  * Copyright (C) 2001 Cyrille Chepelov <chepelov@calixo.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include <config.h>
  24
  25 #include <glib.h>
  26 #include "charconv.h"
  27
  28 #ifdef HAVE_UNICODE
  29 #include <string.h>
  30 #include <unicode.h>
  31 #include <errno.h>
  32
  33 #ifdef HAVE_LANGINFO_CODESET
  34 #include <langinfo.h>
  35 #else /* HAVE_LANGINFO_CODESET */
  36 #ifndef EFAULT_8BIT_CHARSET /* this is a hack until dia talks utf8 internally. */
  37 #define EFAULT_8BIT_CHARSET "ISO-8859-1"
  38 #endif /* !EFAULT_8BIT_CHARSET */
  39 #define CODESET
  40 static const char *nl_langinfo(void) {
  41   return EFAULT_8BIT_CHARSET;
  42 }
  43
  44 #endif /* HAVE_LANGINFO_CODESET */
  45
  46 static unicode_iconv_t conv_u2l = (unicode_iconv_t)0;
  47 static unicode_iconv_t conv_l2u = (unicode_iconv_t)0;
  48
  49 static void
  50 check_conv_l2u(void){
  51   if (conv_u2l==(unicode_iconv_t)0) {
  52     conv_u2l = unicode_iconv_open(nl_langinfo(CODESET),"UTF-8");
  53   }
  54   if (conv_l2u==(unicode_iconv_t)0) {
  55     conv_l2u = unicode_iconv_open("UTF-8",nl_langinfo(CODESET));
  56   }
  57 }
  58
  59 static void
  60 check_conv_u2l(void){
  61   if (conv_u2l==(unicode_iconv_t)0) {
  62     conv_u2l = unicode_iconv_open(nl_langinfo(CODESET),"UTF-8");
  63   }
  64 }
  65
  66
  67 extern gchar *
  68 charconv_local8_to_utf8(const gchar *local)
  69 {
  70   const gchar *l = local;
  71   int lleft = strlen(local);
  72   gchar *utf,*u,*ures;
  73   int uleft;
  74   int lost = 0;
  75
  76   check_conv_l2u();
  77   uleft = 6*lleft + 1;
  78   u = utf = g_malloc(uleft);
  79   *u = 0;
  80   unicode_iconv(conv_l2u,NULL,NULL,NULL,NULL); /* reset the state machines */
  81   while ((uleft) && (lleft)) {
  82     ssize_t res = unicode_iconv(conv_l2u,
  83                                 &l,&lleft,
  84                                 &u,&uleft);
  85     *u = 0;
  86     if (res==(ssize_t)-1) {
  87       g_warning("unicode_iconv(l2u,...) failed, because '%s'",
  88                 strerror(errno));
  89       break;
  90     } else {
  91       lost += (int)res; /* lost chars in the process. */
  92     }
  93   }
  94   ures = g_strdup(utf); /* get the actual size. */
  95   g_free(utf);
  96   return ures;
  97 }
  98
  99 extern gchar *
 100 charconv_utf8_to_local8(const gchar *utf)
 101 {
 102   const gchar *u = utf;
 103   int uleft = strlen(utf);
 104   gchar *local,*l,*lres;
 105   int lleft;
 106   int lost = 0;
 107
 108   check_conv_u2l();
 109   lleft = uleft;
 110   l = local = g_malloc(lleft);
 111   *l = 0;
 112   unicode_iconv(conv_u2l,NULL,NULL,NULL,NULL); /* reset the state machines */
 113   while ((uleft) && (lleft)) {
 114     ssize_t res = unicode_iconv(conv_u2l,
 115                                 &u,&uleft,
 116                                 &l,&lleft);
 117     *l = 0;
 118     if (res==(ssize_t)-1) {
 119       g_warning("unicode_iconv(u2l,...) failed, because '%s'",
 120                 strerror(errno));
 121       break;
 122     } else {
 123       lost += (int)res; /* lost chars in the process. */
 124     }
 125   }
 126   lres = g_strdup(local); /* get the actual size. */
 127   g_free(local);
 128   return lres;
 129 }
 130
 131
 132 #else /* !HAVE_UNICODE */
 133
 134 extern gchar *
 135 charconv_local8_to_utf8(const gchar *local)
 136 {
 137   return g_strdup(local);
 138 }
 139
 140 extern gchar *
 141 charconv_utf8_to_local8(const gchar *utf)
 142 {
 143   return g_strdup(utf);
 144 }
 145
 146 #endif
 147