gl/iconv_open.c

   1 /* Character set conversion.
   2    Copyright (C) 2007 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License along
  15    with this program; if not, write to the Free Software Foundation,
  16    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  17
  18 #include <config.h>
  19
  20 /* Specification.  */
  21 #include <iconv.h>
  22
  23 #include <errno.h>
  24 #include <string.h>
  25 #include "c-ctype.h"
  26
  27 #define SIZEOF(a) (sizeof(a) / sizeof(a[0]))
  28
  29 /* Namespace cleanliness.  */
  30 #define mapping_lookup rpl_iconv_open_mapping_lookup
  31
  32 /* The macro ICONV_FLAVOR is defined to one of these.  */
  33
  34 #define ICONV_FLAVOR_AIX "iconv_open-aix.h"
  35 #define ICONV_FLAVOR_HPUX "iconv_open-hpux.h"
  36 #define ICONV_FLAVOR_IRIX "iconv_open-irix.h"
  37 #define ICONV_FLAVOR_OSF "iconv_open-osf.h"
  38
  39 #include ICONV_FLAVOR
  40
  41 iconv_t
  42 rpl_iconv_open (const char *tocode, const char *fromcode)
  43 #undef iconv_open
  44 {
  45   char fromcode_upper[32];
  46   char tocode_upper[32];
  47   char *fromcode_upper_end;
  48   char *tocode_upper_end;
  49
  50   /* Try with the original names first.
  51      This covers the case when fromcode or tocode is a lowercase encoding name
  52      that is understood by the system's iconv_open but not listed in our
  53      mappings table.  */
  54   {
  55     iconv_t cd = iconv_open (tocode, fromcode);
  56     if (cd != (iconv_t)(-1))
  57       return cd;
  58   }
  59
  60   /* Convert the encodings to upper case, because
  61        1. in the arguments of iconv_open() on AIX, HP-UX, and OSF/1 the case
  62           matters,
  63        2. it makes searching in the table faster.  */
  64   {
  65     const char *p = fromcode;
  66     char *q = fromcode_upper;
  67     while ((*q = c_toupper (*p)) != '\0')
  68       {
  69         p++;
  70         q++;
  71         if (q == &fromcode_upper[SIZEOF (fromcode_upper)])
  72           {
  73             errno = EINVAL;
  74             return (iconv_t)(-1);
  75           }
  76       }
  77     fromcode_upper_end = q;
  78   }
  79
  80   {
  81     const char *p = tocode;
  82     char *q = tocode_upper;
  83     while ((*q = c_toupper (*p)) != '\0')
  84       {
  85         p++;
  86         q++;
  87         if (q == &tocode_upper[SIZEOF (tocode_upper)])
  88           {
  89             errno = EINVAL;
  90             return (iconv_t)(-1);
  91           }
  92       }
  93     tocode_upper_end = q;
  94   }
  95
  96   /* Apply the mappings.  */
  97   {
  98     const struct mapping *m =
  99       mapping_lookup (fromcode_upper, fromcode_upper_end - fromcode_upper);
 100
 101     fromcode = (m != NULL ? m->vendor_name : fromcode_upper);
 102   }
 103   {
 104     const struct mapping *m =
 105       mapping_lookup (tocode_upper, tocode_upper_end - tocode_upper);
 106
 107     tocode = (m != NULL ? m->vendor_name : tocode_upper);
 108   }
 109
 110   return iconv_open (tocode, fromcode);
 111 }