src/iconv_decode_danmarc.c

   1 /* This file is part of the YAZ toolkit.
   2  * Copyright (C) 1995-2012 Index Data
   3  * See the file LICENSE for details.
   4  */
   5 /**
   6  * \file
   7  * \brief Danmarc2 character set decoding
   8  *
   9  */
  10
  11 #if HAVE_CONFIG_H
  12 #include <config.h>
  13 #endif
  14
  15 #include <assert.h>
  16 #include <errno.h>
  17 #include <string.h>
  18 #include <stdio.h>
  19 #include <yaz/log.h>
  20 #include <yaz/xmalloc.h>
  21 #include "iconv-p.h"
  22
  23 struct decoder_data {
  24     unsigned long x_back;
  25 };
  26
  27 static unsigned long read_danmarc(yaz_iconv_t cd,
  28                                   yaz_iconv_decoder_t d,
  29                                   unsigned char *inp,
  30                                   size_t inbytesleft, size_t *no_read)
  31 {
  32     struct decoder_data *data = (struct decoder_data *) d->data;
  33     unsigned long x = inp[0];
  34
  35     if (data->x_back)
  36     {
  37         *no_read = 1;
  38         x = data->x_back;
  39         data->x_back = 0;
  40         return x;
  41     }
  42
  43     if (x == '@')
  44     {
  45         if (inbytesleft < 2)
  46         {
  47             yaz_iconv_set_errno(cd, YAZ_ICONV_EINVAL);
  48             *no_read = 0;
  49             return 0;
  50         }
  51         switch(inp[1])
  52         {
  53         case '@':
  54         case '*':
  55         case 0xa4: /* CURRENCY SIGN */
  56             x = inp[1];
  57             *no_read = 2;
  58             break;
  59         case 0xe5: /* LATIN SMALL LETTER A WITH RING ABOVE */
  60             x = 'a';
  61             data->x_back = 'a';
  62             *no_read = 1;
  63             break;
  64         case 0xc5: /* LATIN CAPITAL LETTER A WITH RING ABOVE */
  65             x = 'A';
  66             data->x_back = 'a';
  67             *no_read = 1;
  68             break;
  69         default:
  70             if (inbytesleft < 5)
  71             {
  72                 yaz_iconv_set_errno(cd, YAZ_ICONV_EINVAL);
  73                 *no_read = 0;
  74                 return 0;
  75             }
  76             else
  77             {
  78                 unsigned long v;
  79                 sscanf((const char *) inp+1, "%4lx", &v);
  80                 *no_read = 5;
  81                 x = v;
  82             }
  83         }
  84     }
  85     else
  86         *no_read = 1;
  87     return x;
  88 }
  89
  90
  91 static size_t init_danmarc(yaz_iconv_t cd, yaz_iconv_decoder_t d,
  92                            unsigned char *inp,
  93                            size_t inbytesleft, size_t *no_read)
  94 {
  95     struct decoder_data *data = (struct decoder_data *) d->data;
  96     data->x_back = 0;
  97     return 0;
  98 }
  99
 100 void destroy_danmarc(yaz_iconv_decoder_t d)
 101 {
 102     struct decoder_data *data = (struct decoder_data *) d->data;
 103     xfree(data);
 104 }
 105
 106 yaz_iconv_decoder_t yaz_danmarc_decoder(const char *fromcode,
 107                                         yaz_iconv_decoder_t d)
 108
 109 {
 110     if (!yaz_matchstr(fromcode, "danmarc"))
 111     {
 112         struct decoder_data *data = (struct decoder_data *)
 113             xmalloc(sizeof(*data));
 114         d->data = data;
 115         data->x_back = 0;
 116         d->read_handle = read_danmarc;
 117         d->init_handle = init_danmarc;
 118         d->destroy_handle = destroy_danmarc;
 119         return d;
 120     }
 121     return 0;
 122 }
 123
 124
 125 /*
 126  * Local variables:
 127  * c-basic-offset: 4
 128  * c-file-style: "Stroustrup"
 129  * indent-tabs-mode: nil
 130  * End:
 131  * vim: shiftwidth=4 tabstop=8 expandtab
 132  */
 133