iconvdata/jis0208.h

   1 /* Access functions for JISX0208 conversion.
   2    Copyright (C) 1997-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _JIS0208_H
  20 #define _JIS0208_H      1
  21
  22 #include <gconv.h>
  23 #include <stdint.h>
  24
  25 /* Struct for table with indices in UCS mapping table.  */
  26 struct jisx0208_ucs_idx
  27 {
  28   uint16_t start;
  29   uint16_t end;
  30   uint16_t idx;
  31 };
  32
  33
  34 /* Conversion table.  */
  35 extern const uint16_t __jis0208_to_ucs[];
  36
  37 #define JIS0208_LAT1_MIN 0xa2
  38 #define JIS0208_LAT1_MAX 0xf7
  39 extern const char __jisx0208_from_ucs4_lat1[JIS0208_LAT1_MAX + 1
  40                                             - JIS0208_LAT1_MIN][2];
  41 extern const char __jisx0208_from_ucs4_greek[0xc1][2];
  42 extern const struct jisx0208_ucs_idx __jisx0208_from_ucs_idx[];
  43 extern const char __jisx0208_from_ucs_tab[][2];
  44
  45
  46 static inline uint32_t
  47 __attribute ((always_inline))
  48 jisx0208_to_ucs4 (const unsigned char **s, size_t avail, unsigned char offset)
  49 {
  50   unsigned char ch = *(*s);
  51   unsigned char ch2;
  52   int idx;
  53
  54   if (ch < offset || (ch - offset) <= 0x20)
  55     return __UNKNOWN_10646_CHAR;
  56
  57   if (avail < 2)
  58     return 0;
  59
  60   ch2 = (*s)[1];
  61   if (ch2 < offset || (ch2 - offset) <= 0x20 || (ch2 - offset) >= 0x7f)
  62     return __UNKNOWN_10646_CHAR;
  63
  64   idx = (ch - 0x21 - offset) * 94 + (ch2 - 0x21 - offset);
  65   if (idx >= 0x1e80)
  66     return __UNKNOWN_10646_CHAR;
  67
  68   (*s) += 2;
  69
  70   return __jis0208_to_ucs[idx] ?: ((*s) -= 2, __UNKNOWN_10646_CHAR);
  71 }
  72
  73
  74 static inline size_t
  75 __attribute ((always_inline))
  76 ucs4_to_jisx0208 (uint32_t wch, unsigned char *s, size_t avail)
  77 {
  78   unsigned int ch = (unsigned int) wch;
  79   const char *cp;
  80
  81   if (avail < 2)
  82     return 0;
  83
  84   if (ch >= JIS0208_LAT1_MIN && ch <= JIS0208_LAT1_MAX)
  85     cp = __jisx0208_from_ucs4_lat1[ch - JIS0208_LAT1_MIN];
  86   else if (ch >= 0x391 && ch <= 0x451)
  87     cp = __jisx0208_from_ucs4_greek[ch - 0x391];
  88   else
  89     {
  90       const struct jisx0208_ucs_idx *rp = __jisx0208_from_ucs_idx;
  91
  92       if (ch >= 0xffff)
  93         return __UNKNOWN_10646_CHAR;
  94       while (ch > rp->end)
  95         ++rp;
  96       if (ch >= rp->start)
  97         cp = __jisx0208_from_ucs_tab[rp->idx + ch - rp->start];
  98       else
  99         return __UNKNOWN_10646_CHAR;
 100     }
 101
 102   if (cp[0] == '\0')
 103     return __UNKNOWN_10646_CHAR;
 104
 105   s[0] = cp[0];
 106   s[1] = cp[1];
 107
 108   return 2;
 109 }
 110
 111 #endif /* jis0208.h */