iconvdata/utf-16.c

   1 /* Conversion module for UTF-16.
   2    Copyright (C) 1999, 2000-2002, 2003, 2005 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 Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the 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    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <byteswap.h>
  22 #include <dlfcn.h>
  23 #include <gconv.h>
  24 #include <stddef.h>
  25 #include <stdint.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /* This is the Byte Order Mark character (BOM).  */
  30 #define BOM     0xfeff
  31 /* And in the other byte order.  */
  32 #define BOM_OE  0xfffe
  33
  34
  35 /* Definitions used in the body of the `gconv' function.  */
  36 #define FROM_LOOP               from_utf16_loop
  37 #define TO_LOOP                 to_utf16_loop
  38 #define DEFINE_INIT             0
  39 #define DEFINE_FINI             0
  40 #define MIN_NEEDED_FROM         2
  41 #define MAX_NEEDED_FROM         4
  42 #define MIN_NEEDED_TO           4
  43 #define FROM_DIRECTION          (dir == from_utf16)
  44 #define PREPARE_LOOP \
  45   enum direction dir = ((struct utf16_data *) step->__data)->dir;             \
  46   enum variant var = ((struct utf16_data *) step->__data)->var;               \
  47   if (__builtin_expect (data->__invocation_counter == 0, 0) && var == UTF_16) \
  48     {                                                                         \
  49       if (FROM_DIRECTION)                                                     \
  50         {                                                                     \
  51           /* We have to find out which byte order the file is encoded in.  */ \
  52           if (inptr + 2 > inend)                                              \
  53             return (inptr == inend                                            \
  54                     ? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);        \
  55                                                                               \
  56           if (get16u (inptr) == BOM)                                          \
  57             /* Simply ignore the BOM character.  */                           \
  58             *inptrp = inptr += 2;                                             \
  59           else if (get16u (inptr) == BOM_OE)                                  \
  60             {                                                                 \
  61               ((struct utf16_data *) step->__data)->swap = 1;                 \
  62               *inptrp = inptr += 2;                                           \
  63             }                                                                 \
  64         }                                                                     \
  65       else if (!FROM_DIRECTION && !data->__internal_use)                      \
  66         {                                                                     \
  67           /* Emit the Byte Order Mark.  */                                    \
  68           if (__builtin_expect (outbuf + 2 > outend, 0))                      \
  69             return __GCONV_FULL_OUTPUT;                                       \
  70                                                                               \
  71           put16u (outbuf, BOM);                                               \
  72           outbuf += 2;                                                        \
  73         }                                                                     \
  74     }                                                                         \
  75   int swap = ((struct utf16_data *) step->__data)->swap;
  76 #define EXTRA_LOOP_ARGS         , swap
  77
  78
  79 /* Direction of the transformation.  */
  80 enum direction
  81 {
  82   illegal_dir,
  83   to_utf16,
  84   from_utf16
  85 };
  86
  87 enum variant
  88 {
  89   illegal_var,
  90   UTF_16,
  91   UTF_16LE,
  92   UTF_16BE
  93 };
  94
  95 struct utf16_data
  96 {
  97   enum direction dir;
  98   enum variant var;
  99   int swap;
 100 };
 101
 102
 103 extern int gconv_init (struct __gconv_step *step);
 104 int
 105 gconv_init (struct __gconv_step *step)
 106 {
 107   /* Determine which direction.  */
 108   struct utf16_data *new_data;
 109   enum direction dir = illegal_dir;
 110   enum variant var = illegal_var;
 111   int result;
 112
 113   if (__strcasecmp (step->__from_name, "UTF-16//") == 0)
 114     {
 115       dir = from_utf16;
 116       var = UTF_16;
 117     }
 118   else if (__strcasecmp (step->__to_name, "UTF-16//") == 0)
 119     {
 120       dir = to_utf16;
 121       var = UTF_16;
 122     }
 123   else if (__strcasecmp (step->__from_name, "UTF-16BE//") == 0)
 124     {
 125       dir = from_utf16;
 126       var = UTF_16BE;
 127     }
 128   else if (__strcasecmp (step->__to_name, "UTF-16BE//") == 0)
 129     {
 130       dir = to_utf16;
 131       var = UTF_16BE;
 132     }
 133   else if (__strcasecmp (step->__from_name, "UTF-16LE//") == 0)
 134     {
 135       dir = from_utf16;
 136       var = UTF_16LE;
 137     }
 138   else if (__strcasecmp (step->__to_name, "UTF-16LE//") == 0)
 139     {
 140       dir = to_utf16;
 141       var = UTF_16LE;
 142     }
 143
 144   result = __GCONV_NOCONV;
 145   if (__builtin_expect (dir, to_utf16) != illegal_dir)
 146     {
 147       new_data = (struct utf16_data *) malloc (sizeof (struct utf16_data));
 148
 149       result = __GCONV_NOMEM;
 150       if (new_data != NULL)
 151         {
 152           new_data->dir = dir;
 153           new_data->var = var;
 154           new_data->swap = ((var == UTF_16LE && BYTE_ORDER == BIG_ENDIAN)
 155                             || (var == UTF_16BE
 156                                 && BYTE_ORDER == LITTLE_ENDIAN));
 157           step->__data = new_data;
 158
 159           if (dir == from_utf16)
 160             {
 161               step->__min_needed_from = MIN_NEEDED_FROM;
 162               step->__max_needed_from = MAX_NEEDED_FROM;
 163               step->__min_needed_to = MIN_NEEDED_TO;
 164               step->__max_needed_to = MIN_NEEDED_TO;
 165             }
 166           else
 167             {
 168               step->__min_needed_from = MIN_NEEDED_TO;
 169               step->__max_needed_from = MIN_NEEDED_TO;
 170               step->__min_needed_to = MIN_NEEDED_FROM;
 171               step->__max_needed_to = MAX_NEEDED_FROM;
 172             }
 173
 174           step->__stateful = 0;
 175
 176           result = __GCONV_OK;
 177         }
 178     }
 179
 180   return result;
 181 }
 182
 183
 184 extern void gconv_end (struct __gconv_step *data);
 185 void
 186 gconv_end (struct __gconv_step *data)
 187 {
 188   free (data->__data);
 189 }
 190
 191
 192 /* Convert from the internal (UCS4-like) format to UTF-16.  */
 193 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 194 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 195 #define MAX_NEEDED_OUTPUT       MAX_NEEDED_FROM
 196 #define LOOPFCT                 TO_LOOP
 197 #define BODY \
 198   {                                                                           \
 199     uint32_t c = get32 (inptr);                                               \
 200                                                                               \
 201     if (__builtin_expect (c >= 0xd800 && c < 0xe000, 0))                      \
 202       {                                                                       \
 203         /* Surrogate characters in UCS-4 input are not valid.                 \
 204            We must catch this.  If we let surrogates pass through,            \
 205            attackers could make a security hole exploit by                    \
 206            synthesizing any desired plane 1-16 character.  */                 \
 207         result = __GCONV_ILLEGAL_INPUT;                                       \
 208         if (! ignore_errors_p ())                                             \
 209           break;                                                              \
 210         inptr += 4;                                                           \
 211         ++*irreversible;                                                      \
 212         continue;                                                             \
 213       }                                                                       \
 214                                                                               \
 215     if (swap)                                                                 \
 216       {                                                                       \
 217         if (__builtin_expect (c >= 0x10000, 0))                               \
 218           {                                                                   \
 219             if (__builtin_expect (c >= 0x110000, 0))                          \
 220               {                                                               \
 221                 STANDARD_TO_LOOP_ERR_HANDLER (4);                             \
 222               }                                                               \
 223                                                                               \
 224             /* Generate a surrogate character.  */                            \
 225             if (__builtin_expect (outptr + 4 > outend, 0))                    \
 226               {                                                               \
 227                 /* Overflow in the output buffer.  */                         \
 228                 result = __GCONV_FULL_OUTPUT;                                 \
 229                 break;                                                        \
 230               }                                                               \
 231                                                                               \
 232             put16 (outptr, bswap_16 (0xd7c0 + (c >> 10)));                    \
 233             outptr += 2;                                                      \
 234             put16 (outptr, bswap_16 (0xdc00 + (c & 0x3ff)));                  \
 235           }                                                                   \
 236         else                                                                  \
 237           put16 (outptr, bswap_16 (c));                                       \
 238       }                                                                       \
 239     else                                                                      \
 240       {                                                                       \
 241         if (__builtin_expect (c >= 0x10000, 0))                               \
 242           {                                                                   \
 243             if (__builtin_expect (c >= 0x110000, 0))                          \
 244               {                                                               \
 245                 STANDARD_TO_LOOP_ERR_HANDLER (4);                             \
 246               }                                                               \
 247                                                                               \
 248             /* Generate a surrogate character.  */                            \
 249             if (__builtin_expect (outptr + 4 > outend, 0))                    \
 250               {                                                               \
 251                 /* Overflow in the output buffer.  */                         \
 252                 result = __GCONV_FULL_OUTPUT;                                 \
 253                 break;                                                        \
 254               }                                                               \
 255                                                                               \
 256             put16 (outptr, 0xd7c0 + (c >> 10));                               \
 257             outptr += 2;                                                      \
 258             put16 (outptr, 0xdc00 + (c & 0x3ff));                             \
 259           }                                                                   \
 260         else                                                                  \
 261           put16 (outptr, c);                                                  \
 262       }                                                                       \
 263     outptr += 2;                                                              \
 264     inptr += 4;                                                               \
 265   }
 266 #define LOOP_NEED_FLAGS
 267 #define EXTRA_LOOP_DECLS \
 268         , int swap
 269 #include <iconv/loop.c>
 270
 271
 272 /* Convert from UTF-16 to the internal (UCS4-like) format.  */
 273 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 274 #define MAX_NEEDED_INPUT        MAX_NEEDED_FROM
 275 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 276 #define LOOPFCT                 FROM_LOOP
 277 #define BODY \
 278   {                                                                           \
 279     uint16_t u1 = get16 (inptr);                                              \
 280                                                                               \
 281     if (swap)                                                                 \
 282       {                                                                       \
 283         u1 = bswap_16 (u1);                                                   \
 284                                                                               \
 285         if (__builtin_expect (u1 < 0xd800, 1) || u1 > 0xdfff)                 \
 286           {                                                                   \
 287             /* No surrogate.  */                                              \
 288             put32 (outptr, u1);                                               \
 289             inptr += 2;                                                       \
 290           }                                                                   \
 291         else                                                                  \
 292           {                                                                   \
 293             uint16_t u2;                                                      \
 294                                                                               \
 295             /* It's a surrogate character.  At least the first word says      \
 296                it is.  */                                                     \
 297             if (__builtin_expect (inptr + 4 > inend, 0))                      \
 298               {                                                               \
 299                 /* We don't have enough input for another complete input      \
 300                    character.  */                                             \
 301                 result = __GCONV_INCOMPLETE_INPUT;                            \
 302                 break;                                                        \
 303               }                                                               \
 304                                                                               \
 305             inptr += 2;                                                       \
 306             u2 = bswap_16 (get16 (inptr));                                    \
 307             if (__builtin_expect (u2 < 0xdc00, 0)                             \
 308                 || __builtin_expect (u2 > 0xdfff, 0))                         \
 309               {                                                               \
 310                 /* This is no valid second word for a surrogate.  */          \
 311                 inptr -= 2;                                                   \
 312                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 313               }                                                               \
 314                                                                               \
 315             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
 316             inptr += 2;                                                       \
 317           }                                                                   \
 318       }                                                                       \
 319     else                                                                      \
 320       {                                                                       \
 321         if (__builtin_expect (u1 < 0xd800, 1) || u1 > 0xdfff)                 \
 322           {                                                                   \
 323             /* No surrogate.  */                                              \
 324             put32 (outptr, u1);                                               \
 325             inptr += 2;                                                       \
 326           }                                                                   \
 327         else                                                                  \
 328           {                                                                   \
 329             /* It's a surrogate character.  At least the first word says      \
 330                it is.  */                                                     \
 331             if (__builtin_expect (inptr + 4 > inend, 0))                      \
 332               {                                                               \
 333                 /* We don't have enough input for another complete input      \
 334                    character.  */                                             \
 335                 result = __GCONV_INCOMPLETE_INPUT;                            \
 336                 break;                                                        \
 337               }                                                               \
 338                                                                               \
 339             inptr += 2;                                                       \
 340             uint16_t u2 = get16 (inptr);                                      \
 341             if (__builtin_expect (u2 < 0xdc00, 0)                             \
 342                 || __builtin_expect (u2 > 0xdfff, 0))                         \
 343               {                                                               \
 344                 /* This is no valid second word for a surrogate.  */          \
 345                 inptr -= 2;                                                   \
 346                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 347               }                                                               \
 348                                                                               \
 349             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
 350             inptr += 2;                                                       \
 351           }                                                                   \
 352       }                                                                       \
 353     outptr += 4;                                                              \
 354   }
 355 #define LOOP_NEED_FLAGS
 356 #define EXTRA_LOOP_DECLS \
 357         , int swap
 358 #include <iconv/loop.c>
 359
 360
 361 /* Now define the toplevel functions.  */
 362 #include <iconv/skeleton.c>