iconvdata/utf-16.c

   1 /* Conversion module for UTF-16.
   2    Copyright (C) 1999-2018 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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <byteswap.h>
  21 #include <dlfcn.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 /* And in the other byte order.  */
  31 #define BOM_OE  0xfffe
  32
  33
  34 /* Definitions used in the body of the `gconv' function.  */
  35 #define FROM_LOOP               from_utf16_loop
  36 #define TO_LOOP                 to_utf16_loop
  37 #define DEFINE_INIT             0
  38 #define DEFINE_FINI             0
  39 #define MIN_NEEDED_FROM         2
  40 #define MAX_NEEDED_FROM         4
  41 #define MIN_NEEDED_TO           4
  42 #define ONE_DIRECTION           0
  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 (__glibc_unlikely (data->__invocation_counter == 0))                     \
  48     {                                                                         \
  49       if (var == UTF_16)                                                      \
  50         {                                                                     \
  51           if (FROM_DIRECTION)                                                 \
  52             {                                                                 \
  53               /* We have to find out which byte order the file is             \
  54                  encoded in.  */                                              \
  55               if (inptr + 2 > inend)                                          \
  56                 return (inptr == inend                                        \
  57                         ? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);    \
  58                                                                               \
  59               if (get16u (inptr) == BOM)                                      \
  60                 /* Simply ignore the BOM character.  */                       \
  61                 *inptrp = inptr += 2;                                         \
  62               else if (get16u (inptr) == BOM_OE)                              \
  63                 {                                                             \
  64                   data->__flags |= __GCONV_SWAP;                              \
  65                   *inptrp = inptr += 2;                                       \
  66                 }                                                             \
  67             }                                                                 \
  68           else if (!FROM_DIRECTION && !data->__internal_use)                  \
  69             {                                                                 \
  70               /* Emit the Byte Order Mark.  */                                \
  71               if (__glibc_unlikely (outbuf + 2 > outend))                     \
  72                 return __GCONV_FULL_OUTPUT;                                   \
  73                                                                               \
  74               put16u (outbuf, BOM);                                           \
  75               outbuf += 2;                                                    \
  76             }                                                                 \
  77         }                                                                     \
  78       else if ((var == UTF_16LE && BYTE_ORDER == BIG_ENDIAN)                  \
  79                || (var == UTF_16BE && BYTE_ORDER == LITTLE_ENDIAN))           \
  80         data->__flags |= __GCONV_SWAP;                                        \
  81     }                                                                         \
  82   const int swap = data->__flags & __GCONV_SWAP;
  83 #define EXTRA_LOOP_ARGS         , swap
  84
  85
  86 /* Direction of the transformation.  */
  87 enum direction
  88 {
  89   illegal_dir,
  90   to_utf16,
  91   from_utf16
  92 };
  93
  94 enum variant
  95 {
  96   illegal_var,
  97   UTF_16,
  98   UTF_16LE,
  99   UTF_16BE
 100 };
 101
 102 struct utf16_data
 103 {
 104   enum direction dir;
 105   enum variant var;
 106 };
 107
 108
 109 extern int gconv_init (struct __gconv_step *step);
 110 int
 111 gconv_init (struct __gconv_step *step)
 112 {
 113   /* Determine which direction.  */
 114   struct utf16_data *new_data;
 115   enum direction dir = illegal_dir;
 116   enum variant var = illegal_var;
 117   int result;
 118
 119   if (__strcasecmp (step->__from_name, "UTF-16//") == 0)
 120     {
 121       dir = from_utf16;
 122       var = UTF_16;
 123     }
 124   else if (__strcasecmp (step->__to_name, "UTF-16//") == 0)
 125     {
 126       dir = to_utf16;
 127       var = UTF_16;
 128     }
 129   else if (__strcasecmp (step->__from_name, "UTF-16BE//") == 0)
 130     {
 131       dir = from_utf16;
 132       var = UTF_16BE;
 133     }
 134   else if (__strcasecmp (step->__to_name, "UTF-16BE//") == 0)
 135     {
 136       dir = to_utf16;
 137       var = UTF_16BE;
 138     }
 139   else if (__strcasecmp (step->__from_name, "UTF-16LE//") == 0)
 140     {
 141       dir = from_utf16;
 142       var = UTF_16LE;
 143     }
 144   else if (__strcasecmp (step->__to_name, "UTF-16LE//") == 0)
 145     {
 146       dir = to_utf16;
 147       var = UTF_16LE;
 148     }
 149
 150   result = __GCONV_NOCONV;
 151   if (__builtin_expect (dir, to_utf16) != illegal_dir)
 152     {
 153       new_data = (struct utf16_data *) malloc (sizeof (struct utf16_data));
 154
 155       result = __GCONV_NOMEM;
 156       if (new_data != NULL)
 157         {
 158           new_data->dir = dir;
 159           new_data->var = var;
 160           step->__data = new_data;
 161
 162           if (dir == from_utf16)
 163             {
 164               step->__min_needed_from = MIN_NEEDED_FROM;
 165               step->__max_needed_from = MAX_NEEDED_FROM;
 166               step->__min_needed_to = MIN_NEEDED_TO;
 167               step->__max_needed_to = MIN_NEEDED_TO;
 168             }
 169           else
 170             {
 171               step->__min_needed_from = MIN_NEEDED_TO;
 172               step->__max_needed_from = MIN_NEEDED_TO;
 173               step->__min_needed_to = MIN_NEEDED_FROM;
 174               step->__max_needed_to = MAX_NEEDED_FROM;
 175             }
 176
 177           step->__stateful = 0;
 178
 179           result = __GCONV_OK;
 180         }
 181     }
 182
 183   return result;
 184 }
 185
 186
 187 extern void gconv_end (struct __gconv_step *data);
 188 void
 189 gconv_end (struct __gconv_step *data)
 190 {
 191   free (data->__data);
 192 }
 193
 194
 195 /* Convert from the internal (UCS4-like) format to UTF-16.  */
 196 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 197 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 198 #define MAX_NEEDED_OUTPUT       MAX_NEEDED_FROM
 199 #define LOOPFCT                 TO_LOOP
 200 #define BODY \
 201   {                                                                           \
 202     uint32_t c = get32 (inptr);                                               \
 203                                                                               \
 204     if (__glibc_unlikely (c >= 0xd800 && c < 0xe000))                         \
 205       {                                                                       \
 206         /* Surrogate characters in UCS-4 input are not valid.                 \
 207            We must catch this.  If we let surrogates pass through,            \
 208            attackers could make a security hole exploit by                    \
 209            synthesizing any desired plane 1-16 character.  */                 \
 210         result = __GCONV_ILLEGAL_INPUT;                                       \
 211         if (! ignore_errors_p ())                                             \
 212           break;                                                              \
 213         inptr += 4;                                                           \
 214         ++*irreversible;                                                      \
 215         continue;                                                             \
 216       }                                                                       \
 217                                                                               \
 218     if (swap)                                                                 \
 219       {                                                                       \
 220         if (__glibc_unlikely (c >= 0x10000))                                  \
 221           {                                                                   \
 222             if (__glibc_unlikely (c >= 0x110000))                             \
 223               {                                                               \
 224                 STANDARD_TO_LOOP_ERR_HANDLER (4);                             \
 225               }                                                               \
 226                                                                               \
 227             /* Generate a surrogate character.  */                            \
 228             if (__glibc_unlikely (outptr + 4 > outend))                       \
 229               {                                                               \
 230                 /* Overflow in the output buffer.  */                         \
 231                 result = __GCONV_FULL_OUTPUT;                                 \
 232                 break;                                                        \
 233               }                                                               \
 234                                                                               \
 235             put16 (outptr, bswap_16 (0xd7c0 + (c >> 10)));                    \
 236             outptr += 2;                                                      \
 237             put16 (outptr, bswap_16 (0xdc00 + (c & 0x3ff)));                  \
 238           }                                                                   \
 239         else                                                                  \
 240           put16 (outptr, bswap_16 (c));                                       \
 241       }                                                                       \
 242     else                                                                      \
 243       {                                                                       \
 244         if (__glibc_unlikely (c >= 0x10000))                                  \
 245           {                                                                   \
 246             if (__glibc_unlikely (c >= 0x110000))                             \
 247               {                                                               \
 248                 STANDARD_TO_LOOP_ERR_HANDLER (4);                             \
 249               }                                                               \
 250                                                                               \
 251             /* Generate a surrogate character.  */                            \
 252             if (__glibc_unlikely (outptr + 4 > outend))                       \
 253               {                                                               \
 254                 /* Overflow in the output buffer.  */                         \
 255                 result = __GCONV_FULL_OUTPUT;                                 \
 256                 break;                                                        \
 257               }                                                               \
 258                                                                               \
 259             put16 (outptr, 0xd7c0 + (c >> 10));                               \
 260             outptr += 2;                                                      \
 261             put16 (outptr, 0xdc00 + (c & 0x3ff));                             \
 262           }                                                                   \
 263         else                                                                  \
 264           put16 (outptr, c);                                                  \
 265       }                                                                       \
 266     outptr += 2;                                                              \
 267     inptr += 4;                                                               \
 268   }
 269 #define LOOP_NEED_FLAGS
 270 #define EXTRA_LOOP_DECLS \
 271         , int swap
 272 #include <iconv/loop.c>
 273
 274
 275 /* Convert from UTF-16 to the internal (UCS4-like) format.  */
 276 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 277 #define MAX_NEEDED_INPUT        MAX_NEEDED_FROM
 278 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 279 #define LOOPFCT                 FROM_LOOP
 280 #define BODY \
 281   {                                                                           \
 282     uint16_t u1 = get16 (inptr);                                              \
 283                                                                               \
 284     if (swap)                                                                 \
 285       {                                                                       \
 286         u1 = bswap_16 (u1);                                                   \
 287                                                                               \
 288         if (__builtin_expect (u1 < 0xd800, 1) || u1 > 0xdfff)                 \
 289           {                                                                   \
 290             /* No surrogate.  */                                              \
 291             put32 (outptr, u1);                                               \
 292             inptr += 2;                                                       \
 293           }                                                                   \
 294         else                                                                  \
 295           {                                                                   \
 296             uint16_t u2;                                                      \
 297                                                                               \
 298             if (__glibc_unlikely (u1 >= 0xdc00))                              \
 299               {                                                               \
 300                 /* This is no valid first word for a surrogate.  */           \
 301                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 302               }                                                               \
 303                                                                               \
 304             /* It's a surrogate character.  At least the first word says      \
 305                it is.  */                                                     \
 306             if (__glibc_unlikely (inptr + 4 > inend))                         \
 307               {                                                               \
 308                 /* We don't have enough input for another complete input      \
 309                    character.  */                                             \
 310                 result = __GCONV_INCOMPLETE_INPUT;                            \
 311                 break;                                                        \
 312               }                                                               \
 313                                                                               \
 314             inptr += 2;                                                       \
 315             u2 = bswap_16 (get16 (inptr));                                    \
 316             if (__builtin_expect (u2 < 0xdc00, 0)                             \
 317                 || __builtin_expect (u2 > 0xdfff, 0))                         \
 318               {                                                               \
 319                 /* This is no valid second word for a surrogate.  */          \
 320                 inptr -= 2;                                                   \
 321                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 322               }                                                               \
 323                                                                               \
 324             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
 325             inptr += 2;                                                       \
 326           }                                                                   \
 327       }                                                                       \
 328     else                                                                      \
 329       {                                                                       \
 330         if (__builtin_expect (u1 < 0xd800, 1) || u1 > 0xdfff)                 \
 331           {                                                                   \
 332             /* No surrogate.  */                                              \
 333             put32 (outptr, u1);                                               \
 334             inptr += 2;                                                       \
 335           }                                                                   \
 336         else                                                                  \
 337           {                                                                   \
 338             if (__glibc_unlikely (u1 >= 0xdc00))                              \
 339               {                                                               \
 340                 /* This is no valid first word for a surrogate.  */           \
 341                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 342               }                                                               \
 343                                                                               \
 344             /* It's a surrogate character.  At least the first word says      \
 345                it is.  */                                                     \
 346             if (__glibc_unlikely (inptr + 4 > inend))                         \
 347               {                                                               \
 348                 /* We don't have enough input for another complete input      \
 349                    character.  */                                             \
 350                 result = __GCONV_INCOMPLETE_INPUT;                            \
 351                 break;                                                        \
 352               }                                                               \
 353                                                                               \
 354             inptr += 2;                                                       \
 355             uint16_t u2 = get16 (inptr);                                      \
 356             if (__builtin_expect (u2 < 0xdc00, 0)                             \
 357                 || __builtin_expect (u2 > 0xdfff, 0))                         \
 358               {                                                               \
 359                 /* This is no valid second word for a surrogate.  */          \
 360                 inptr -= 2;                                                   \
 361                 STANDARD_FROM_LOOP_ERR_HANDLER (2);                           \
 362               }                                                               \
 363                                                                               \
 364             put32 (outptr, ((u1 - 0xd7c0) << 10) + (u2 - 0xdc00));            \
 365             inptr += 2;                                                       \
 366           }                                                                   \
 367       }                                                                       \
 368     outptr += 4;                                                              \
 369   }
 370 #define LOOP_NEED_FLAGS
 371 #define EXTRA_LOOP_DECLS \
 372         , int swap
 373 #include <iconv/loop.c>
 374
 375
 376 /* Now define the toplevel functions.  */
 377 #include <iconv/skeleton.c>