iconvdata/utf-16.c

   1 /* Conversion module for UTF-16.
   2    Copyright (C) 1999, 2000 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <byteswap.h>
  22 #include <gconv.h>
  23 #include <stddef.h>
  24 #include <stdint.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 /* This is the Byte Order Mark character (BOM).  */
  29 #define BOM     0xfeff
  30
  31
  32 /* Definitions used in the body of the `gconv' function.  */
  33 #define FROM_LOOP               from_utf16_loop
  34 #define TO_LOOP                 to_utf16_loop
  35 #define DEFINE_INIT             0
  36 #define DEFINE_FINI             0
  37 #define MIN_NEEDED_FROM         2
  38 #define MAX_NEEDED_FROM         4
  39 #define MIN_NEEDED_TO           4
  40 #define FROM_DIRECTION          (dir == from_utf16)
  41 #define PREPARE_LOOP \
  42   enum direction dir = ((struct utf16_data *) step->__data)->dir;             \
  43   enum variant var = ((struct utf16_data *) step->__data)->var;               \
  44   if (!FROM_DIRECTION && var == UTF_16 && !data->__internal_use               \
  45       && data->__invocation_counter == 0)                                     \
  46     {                                                                         \
  47       /* Emit the Byte Order Mark.  */                                        \
  48       if (outbuf + 2 > outend)                                                \
  49         return __GCONV_FULL_OUTPUT;                                           \
  50                                                                               \
  51       *(uint16_t *) outbuf = BOM;                                             \
  52       outbuf += 2;                                                            \
  53     }
  54 #define EXTRA_LOOP_ARGS         , var, data
  55
  56
  57 /* Direction of the transformation.  */
  58 enum direction
  59 {
  60   illegal_dir,
  61   to_utf16,
  62   from_utf16
  63 };
  64
  65 enum variant
  66 {
  67   illegal_var,
  68   UTF_16,
  69   UTF_16LE,
  70   UTF_16BE
  71 };
  72
  73 struct utf16_data
  74 {
  75   enum direction dir;
  76   enum variant var;
  77 };
  78
  79
  80 int
  81 gconv_init (struct __gconv_step *step)
  82 {
  83   /* Determine which direction.  */
  84   struct utf16_data *new_data;
  85   enum direction dir = illegal_dir;
  86   enum variant var = illegal_var;
  87   int result;
  88
  89   if (__strcasecmp (step->__from_name, "UTF-16") == 0)
  90     {
  91       dir = from_utf16;
  92       var = UTF_16;
  93     }
  94   else if (__strcasecmp (step->__to_name, "UTF-16") == 0)
  95     {
  96       dir = to_utf16;
  97       var = UTF_16;
  98     }
  99   else if (__strcasecmp (step->__from_name, "UTF-16BE") == 0)
 100     {
 101       dir = from_utf16;
 102       var = UTF_16BE;
 103     }
 104   else if (__strcasecmp (step->__to_name, "UTF-16BE") == 0)
 105     {
 106       dir = to_utf16;
 107       var = UTF_16BE;
 108     }
 109   else if (__strcasecmp (step->__from_name, "UTF-16LE") == 0)
 110     {
 111       dir = from_utf16;
 112       var = UTF_16LE;
 113     }
 114   else if (__strcasecmp (step->__to_name, "UTF-16LE") == 0)
 115     {
 116       dir = to_utf16;
 117       var = UTF_16LE;
 118     }
 119
 120   result = __GCONV_NOCONV;
 121   if (dir != illegal_dir)
 122     {
 123       new_data = (struct utf16_data *) malloc (sizeof (struct utf16_data));
 124
 125       result = __GCONV_NOMEM;
 126       if (new_data != NULL)
 127         {
 128           new_data->dir = dir;
 129           new_data->var = var;
 130           step->__data = new_data;
 131
 132           if (dir == from_utf16)
 133             {
 134               step->__min_needed_from = MIN_NEEDED_FROM;
 135               step->__max_needed_from = MIN_NEEDED_FROM;
 136               step->__min_needed_to = MIN_NEEDED_TO;
 137               step->__max_needed_to = MIN_NEEDED_TO;
 138             }
 139           else
 140             {
 141               step->__min_needed_from = MIN_NEEDED_TO;
 142               step->__max_needed_from = MIN_NEEDED_TO;
 143               step->__min_needed_to = MIN_NEEDED_FROM;
 144               step->__max_needed_to = MIN_NEEDED_FROM;
 145             }
 146
 147           step->__stateful = 0;
 148
 149           result = __GCONV_OK;
 150         }
 151     }
 152
 153   return result;
 154 }
 155
 156
 157 void
 158 gconv_end (struct __gconv_step *data)
 159 {
 160   free (data->__data);
 161 }
 162
 163
 164 /* Convert from the internal (UCS4-like) format to UTF-16.  */
 165 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 166 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 167 #define MAX_NEEDED_OUTPUT       MAX_NEEDED_FROM
 168 #define LOOPFCT                 TO_LOOP
 169 #define BODY \
 170   {                                                                           \
 171     uint32_t c = *((uint32_t *) inptr);                                       \
 172                                                                               \
 173     if ((__BYTE_ORDER == __LITTLE_ENDIAN && var == UTF_16BE)                  \
 174         || (__BYTE_ORDER == __BIG_ENDIAN && var == UTF_16LE))                 \
 175       {                                                                       \
 176         if (c >= 0x10000)                                                     \
 177           {                                                                   \
 178             if (c >= 0x110000)                                                \
 179               {                                                               \
 180                 result = __GCONV_ILLEGAL_INPUT;                               \
 181                 break;                                                        \
 182               }                                                               \
 183                                                                               \
 184             /* Generate a surrogate character.  */                            \
 185             if (NEED_LENGTH_TEST && outptr + 4 > outend)                      \
 186               {                                                               \
 187                 /* Overflow in the output buffer.  */                         \
 188                 result = __GCONV_FULL_OUTPUT;                                 \
 189                 break;                                                        \
 190               }                                                               \
 191                                                                               \
 192             *((uint16_t *) outptr) = bswap_16 (0xd7c0 + (c >> 10));           \
 193             outptr += 2;                                                      \
 194             *((uint16_t *) outptr) = bswap_16 (0xdc00 + (c & 0x3ff));         \
 195           }                                                                   \
 196         else                                                                  \
 197           *((uint16_t *) outptr) = bswap_16 (c);                              \
 198       }                                                                       \
 199     else                                                                      \
 200       {                                                                       \
 201         if (c >= 0x10000)                                                     \
 202           {                                                                   \
 203             if (c >= 0x110000)                                                \
 204               {                                                               \
 205                 result = __GCONV_ILLEGAL_INPUT;                               \
 206                 break;                                                        \
 207               }                                                               \
 208                                                                               \
 209             /* Generate a surrogate character.  */                            \
 210             if (NEED_LENGTH_TEST && outptr + 4 > outend)                      \
 211               {                                                               \
 212                 /* Overflow in the output buffer.  */                         \
 213                 result = __GCONV_FULL_OUTPUT;                                 \
 214                 break;                                                        \
 215               }                                                               \
 216                                                                               \
 217             *((uint16_t *) outptr) = 0xd7c0 + (c >> 10);                      \
 218             outptr += 2;                                                      \
 219             *((uint16_t *) outptr) = 0xdc00 + (c & 0x3ff);                    \
 220           }                                                                   \
 221         else                                                                  \
 222           *((uint16_t *) outptr) = c;                                         \
 223       }                                                                       \
 224     outptr += 2;                                                              \
 225     inptr += 4;                                                               \
 226   }
 227 #define EXTRA_LOOP_DECLS \
 228         , enum variant var, struct __gconv_step_data *step_data
 229 #include <iconv/loop.c>
 230
 231
 232 /* Convert from UTF-16 to the internal (UCS4-like) format.  */
 233 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 234 #define MAX_NEEDED_INPUT        MAX_NEEDED_FROM
 235 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 236 #define LOOPFCT                 FROM_LOOP
 237 #define BODY \
 238   {                                                                           \
 239     uint16_t u1 = *(uint16_t *) inptr;                                        \
 240                                                                               \
 241     if ((__BYTE_ORDER == __LITTLE_ENDIAN && var == UTF_16BE)                  \
 242         || (__BYTE_ORDER == __BIG_ENDIAN && var == UTF_16LE))                 \
 243       {                                                                       \
 244         u1 = bswap_16 (u1);                                                   \
 245                                                                               \
 246         if (u1 < 0xd800 || u1 > 0xdfff)                                       \
 247           {                                                                   \
 248             /* No surrogate.  */                                              \
 249             *((uint32_t *) outptr) = u1;                                      \
 250             inptr += 2;                                                       \
 251           }                                                                   \
 252         else                                                                  \
 253           {                                                                   \
 254             uint16_t u2;                                                      \
 255                                                                               \
 256             /* It's a surrogate character.  At least the first word says      \
 257                it is.  */                                                     \
 258             if (NEED_LENGTH_TEST && inptr + 4 > inend)                        \
 259               {                                                               \
 260                 /* We don't have enough input for another complete input      \
 261                    character.  */                                             \
 262                 result = __GCONV_INCOMPLETE_INPUT;                            \
 263                 break;                                                        \
 264               }                                                               \
 265                                                                               \
 266             u2 = bswap_16 (((uint16_t *) inptr)[1]);                          \
 267             if (u2 < 0xdc00 || u2 >= 0xdfff)                                  \
 268               {                                                               \
 269                 /* This is no valid second word for a surrogate.  */          \
 270                 result = __GCONV_ILLEGAL_INPUT;                               \
 271                 break;                                                        \
 272               }                                                               \
 273                                                                               \
 274             *((uint32_t *) outptr) = ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00);   \
 275             inptr += 4;                                                       \
 276           }                                                                   \
 277       }                                                                       \
 278     else                                                                      \
 279       {                                                                       \
 280         if (u1 == BOM && var == UTF_16 && !step_data->__internal_use          \
 281             && step_data->__invocation_counter == 0 && inptr == *inptrp)      \
 282           {                                                                   \
 283             /* This is the first word in the file and it is the BOM and       \
 284                we are converting a file without specified byte order.         \
 285                Simply sack the BOM.  */                                       \
 286             inptr += 2;                                                       \
 287             continue;                                                         \
 288           }                                                                   \
 289                                                                               \
 290         if (u1 < 0xd800 || u1 > 0xdfff)                                       \
 291           {                                                                   \
 292             /* No surrogate.  */                                              \
 293             *((uint32_t *) outptr) = u1;                                      \
 294             inptr += 2;                                                       \
 295           }                                                                   \
 296         else                                                                  \
 297           {                                                                   \
 298             uint16_t u2;                                                      \
 299                                                                               \
 300             /* It's a surrogate character.  At least the first word says      \
 301                it is.  */                                                     \
 302             if (NEED_LENGTH_TEST && inptr + 4 > inend)                        \
 303               {                                                               \
 304                 /* We don't have enough input for another complete input      \
 305                    character.  */                                             \
 306                 result = __GCONV_INCOMPLETE_INPUT;                            \
 307                 break;                                                        \
 308               }                                                               \
 309                                                                               \
 310             u2 = ((uint16_t *) inptr)[1];                                     \
 311             if (u2 < 0xdc00 || u2 >= 0xdfff)                                  \
 312               {                                                               \
 313                 /* This is no valid second word for a surrogate.  */          \
 314                 result = __GCONV_ILLEGAL_INPUT;                               \
 315                 break;                                                        \
 316               }                                                               \
 317                                                                               \
 318             *((uint32_t *) outptr) = ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00);   \
 319             inptr += 4;                                                       \
 320           }                                                                   \
 321       }                                                                       \
 322     outptr += 4;                                                              \
 323   }
 324 #define EXTRA_LOOP_DECLS \
 325         , enum variant var, struct __gconv_step_data *step_data
 326 #include <iconv/loop.c>
 327
 328
 329 /* Now define the toplevel functions.  */
 330 #include <iconv/skeleton.c>