iconvdata/iso-2022-cn.c

   1 /* Conversion module for ISO-2022-CN.
   2    Copyright (C) 1999-2021 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    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <dlfcn.h>
  21 #include <gconv.h>
  22 #include <stdint.h>
  23 #include <string.h>
  24 #include "gb2312.h"
  25 #include "cns11643l1.h"
  26 #include "cns11643l2.h"
  27
  28 #include <assert.h>
  29
  30 /* This makes obvious what everybody knows: 0x1b is the Esc character.  */
  31 #define ESC     0x1b
  32
  33 /* We have single-byte shift-in and shift-out sequences, and the single
  34    shift sequence SS2 which replaces the SS2 designation for the next
  35    two bytes.  */
  36 #define SI      0x0f
  37 #define SO      0x0e
  38 #define SS2_0   ESC
  39 #define SS2_1   0x4e
  40
  41 /* Definitions used in the body of the `gconv' function.  */
  42 #define CHARSET_NAME            "ISO-2022-CN//"
  43 #define DEFINE_INIT             1
  44 #define DEFINE_FINI             1
  45 #define FROM_LOOP               from_iso2022cn_loop
  46 #define TO_LOOP                 to_iso2022cn_loop
  47 #define ONE_DIRECTION                   0
  48 #define FROM_LOOP_MIN_NEEDED_FROM       1
  49 #define FROM_LOOP_MAX_NEEDED_FROM       4
  50 #define FROM_LOOP_MIN_NEEDED_TO         4
  51 #define FROM_LOOP_MAX_NEEDED_TO         4
  52 #define TO_LOOP_MIN_NEEDED_FROM         4
  53 #define TO_LOOP_MAX_NEEDED_FROM         4
  54 #define TO_LOOP_MIN_NEEDED_TO           1
  55 #define TO_LOOP_MAX_NEEDED_TO           6
  56 #define PREPARE_LOOP \
  57   int save_set;                                                               \
  58   int *setp = &data->__statep->__count;
  59 #define EXTRA_LOOP_ARGS         , setp
  60
  61
  62 /* The COUNT element of the state keeps track of the currently selected
  63    character set.  The possible values are:  */
  64 enum
  65 {
  66   ASCII_set = 0,
  67   GB2312_set = 8,
  68   CNS11643_1_set = 16,
  69   CNS11643_2_set = 24,
  70   CURRENT_SEL_MASK = 24,
  71   GB2312_ann = 32,
  72   CNS11643_1_ann = 64,
  73   CNS11643_2_ann = 128,
  74   CURRENT_ANN_MASK = 224
  75 };
  76
  77
  78 /* Since this is a stateful encoding we have to provide code which resets
  79    the output state to the initial state.  This has to be done during the
  80    flushing.  */
  81 #define EMIT_SHIFT_TO_INIT \
  82   if (data->__statep->__count != ASCII_set)                                   \
  83     {                                                                         \
  84       if (FROM_DIRECTION)                                                     \
  85         /* It's easy, we don't have to emit anything, we just reset the       \
  86            state for the input.  */                                           \
  87         data->__statep->__count = ASCII_set;                                  \
  88       else                                                                    \
  89         {                                                                     \
  90           /* We are not in the initial state.  To switch back we have         \
  91              to emit `SI'.  */                                                \
  92           if (__glibc_unlikely (outbuf == outend))                            \
  93             /* We don't have enough room in the output buffer.  */            \
  94             status = __GCONV_FULL_OUTPUT;                                     \
  95           else                                                                \
  96             {                                                                 \
  97               /* Write out the shift sequence.  */                            \
  98               *outbuf++ = SI;                                                 \
  99               data->__statep->__count = ASCII_set;                            \
 100             }                                                                 \
 101         }                                                                     \
 102     }
 103
 104
 105 /* Since we might have to reset input pointer we must be able to save
 106    and retore the state.  */
 107 #define SAVE_RESET_STATE(Save) \
 108   if (Save)                                                                   \
 109     save_set = *setp;                                                         \
 110   else                                                                        \
 111     *setp = save_set
 112
 113
 114 /* First define the conversion function from ISO-2022-CN to UCS4.  */
 115 #define MIN_NEEDED_INPUT        FROM_LOOP_MIN_NEEDED_FROM
 116 #define MAX_NEEDED_INPUT        FROM_LOOP_MAX_NEEDED_FROM
 117 #define MIN_NEEDED_OUTPUT       FROM_LOOP_MIN_NEEDED_TO
 118 #define MAX_NEEDED_OUTPUT       FROM_LOOP_MAX_NEEDED_TO
 119 #define LOOPFCT                 FROM_LOOP
 120 #define BODY \
 121   {                                                                           \
 122     uint32_t ch = *inptr;                                                     \
 123                                                                               \
 124     /* This is a 7bit character set, disallow all 8bit characters.  */        \
 125     if (__glibc_unlikely (ch >= 0x7f))                                        \
 126       STANDARD_FROM_LOOP_ERR_HANDLER (1);                                     \
 127                                                                               \
 128     /* Recognize escape sequences.  */                                        \
 129     if (__builtin_expect (ch, 0) == ESC)                                      \
 130       {                                                                       \
 131         /* There are two kinds of escape sequences we have to handle:         \
 132            - those announcing the use of GB and CNS characters on the         \
 133              line; we can simply ignore them                                  \
 134            - the initial byte of the SS2 sequence.                            \
 135         */                                                                    \
 136         if (__builtin_expect (inptr + 2 > inend, 0)                           \
 137             || (inptr[1] == '$'                                               \
 138                 && (__builtin_expect (inptr + 3 > inend, 0)                   \
 139                     || (inptr[2] == ')'                                       \
 140                         && __builtin_expect (inptr + 4 > inend, 0))           \
 141                     || (inptr[2] == '*'                                       \
 142                         && __builtin_expect (inptr + 4 > inend, 0))))         \
 143             || (inptr[1] == SS2_1                                             \
 144                 && __builtin_expect (inptr + 4 > inend, 0)))                  \
 145           {                                                                   \
 146             result = __GCONV_INCOMPLETE_INPUT;                                \
 147             break;                                                            \
 148           }                                                                   \
 149         if (inptr[1] == '$'                                                   \
 150             && ((inptr[2] == ')' && (inptr[3] == 'A' || inptr[3] == 'G'))     \
 151                 || (inptr[2] == '*' && inptr[3] == 'H')))                     \
 152           {                                                                   \
 153             /* OK, we accept those character sets.  */                        \
 154             if (inptr[3] == 'A')                                              \
 155               ann = GB2312_ann;                                               \
 156             else if (inptr[3] == 'G')                                         \
 157               ann = CNS11643_1_ann;                                           \
 158             inptr += 4;                                                       \
 159             continue;                                                         \
 160           }                                                                   \
 161       }                                                                       \
 162     else if (__builtin_expect (ch, 0) == SO)                                  \
 163       {                                                                       \
 164         /* Switch to use GB2312 or CNS 11643 plane 1, depending on which      \
 165            S0 designation came last.  The only problem is what to do with     \
 166            faulty input files where no designator came.                       \
 167            XXX For now I'll default to use GB2312.  If this is not the        \
 168            best behaviour (e.g., we should flag an error) let me know.  */    \
 169         ++inptr;                                                              \
 170         set = ann == CNS11643_1_ann ? CNS11643_1_set : GB2312_set;            \
 171         continue;                                                             \
 172       }                                                                       \
 173     else if (__builtin_expect (ch, 0) == SI)                                  \
 174       {                                                                       \
 175         /* Switch to use ASCII.  */                                           \
 176         ++inptr;                                                              \
 177         set = ASCII_set;                                                      \
 178         continue;                                                             \
 179       }                                                                       \
 180                                                                               \
 181     if (__builtin_expect (ch, 0) == ESC && inptr[1] == SS2_1)                 \
 182       {                                                                       \
 183         /* This is a character from CNS 11643 plane 2.                        \
 184            XXX We could test here whether the use of this character           \
 185            set was announced.  */                                             \
 186         inptr += 2;                                                           \
 187         ch = cns11643l2_to_ucs4 (&inptr, 2, 0);                               \
 188         if (__builtin_expect (ch, 0) == __UNKNOWN_10646_CHAR)                 \
 189           {                                                                   \
 190             inptr -= 2;                                                       \
 191             STANDARD_FROM_LOOP_ERR_HANDLER (2);                               \
 192           }                                                                   \
 193       }                                                                       \
 194     else if (set == ASCII_set)                                                \
 195       {                                                                       \
 196         /* Almost done, just advance the input pointer.  */                   \
 197         ++inptr;                                                              \
 198       }                                                                       \
 199     else                                                                      \
 200       {                                                                       \
 201         /* That's pretty easy, we have a dedicated functions for this.  */    \
 202         if (set == GB2312_set)                                                \
 203           ch = gb2312_to_ucs4 (&inptr, inend - inptr, 0);                     \
 204         else                                                                  \
 205           {                                                                   \
 206             assert (set == CNS11643_1_set);                                   \
 207             ch = cns11643l1_to_ucs4 (&inptr, inend - inptr, 0);               \
 208           }                                                                   \
 209                                                                               \
 210         if (__builtin_expect (ch, 1) == 0)                                    \
 211           {                                                                   \
 212             result = __GCONV_INCOMPLETE_INPUT;                                \
 213             break;                                                            \
 214           }                                                                   \
 215         else if (__builtin_expect (ch, 1) == __UNKNOWN_10646_CHAR)            \
 216           {                                                                   \
 217             STANDARD_FROM_LOOP_ERR_HANDLER (1);                               \
 218           }                                                                   \
 219       }                                                                       \
 220                                                                               \
 221     put32 (outptr, ch);                                                       \
 222     outptr += 4;                                                              \
 223   }
 224 #define LOOP_NEED_FLAGS
 225 #define EXTRA_LOOP_DECLS        , int *setp
 226 #define INIT_PARAMS             int set = *setp & CURRENT_SEL_MASK; \
 227                                 int ann = *setp & CURRENT_ANN_MASK
 228 #define UPDATE_PARAMS           *setp = set | ann
 229 #include <iconv/loop.c>
 230
 231
 232 /* Next, define the other direction.  */
 233 #define MIN_NEEDED_INPUT        TO_LOOP_MIN_NEEDED_FROM
 234 #define MAX_NEEDED_INPUT        TO_LOOP_MAX_NEEDED_FROM
 235 #define MIN_NEEDED_OUTPUT       TO_LOOP_MIN_NEEDED_TO
 236 #define MAX_NEEDED_OUTPUT       TO_LOOP_MAX_NEEDED_TO
 237 #define LOOPFCT                 TO_LOOP
 238 #define BODY \
 239   {                                                                           \
 240     uint32_t ch = get32 (inptr);                                              \
 241                                                                               \
 242     /* First see whether we can write the character using the currently       \
 243        selected character set.  */                                            \
 244     if (ch < 0x80)                                                            \
 245       {                                                                       \
 246         if (set != ASCII_set)                                                 \
 247           {                                                                   \
 248             *outptr++ = SI;                                                   \
 249             set = ASCII_set;                                                  \
 250             if (__glibc_unlikely (outptr == outend))                          \
 251               {                                                               \
 252                 result = __GCONV_FULL_OUTPUT;                                 \
 253                 break;                                                        \
 254               }                                                               \
 255           }                                                                   \
 256                                                                               \
 257         *outptr++ = ch;                                                       \
 258                                                                               \
 259         /* At the end of the line we have to clear the `ann' flags since      \
 260            every line must contain this information again.  */                \
 261         if (ch == L'\n')                                                      \
 262           ann = 0;                                                            \
 263       }                                                                       \
 264     else                                                                      \
 265       {                                                                       \
 266         unsigned char buf[2];                                                 \
 267         /* Fake initialization to keep gcc quiet.  */                         \
 268         asm ("" : "=m" (buf));                                                \
 269                                                                               \
 270         int used;                                                             \
 271         size_t written = 0;                                                   \
 272                                                                               \
 273         if (set == GB2312_set || (ann & CNS11643_1_ann) == 0)                 \
 274           {                                                                   \
 275             written = ucs4_to_gb2312 (ch, buf, 2);                            \
 276             used = GB2312_set;                                                \
 277           }                                                                   \
 278         else                                                                  \
 279           {                                                                   \
 280             written = ucs4_to_cns11643l1 (ch, buf, 2);                        \
 281             used = CNS11643_1_set;                                            \
 282           }                                                                   \
 283                                                                               \
 284         if (written == __UNKNOWN_10646_CHAR)                                  \
 285           {                                                                   \
 286             /* Cannot convert it using the currently selected SO set.         \
 287                Next try the SS2 set.  */                                      \
 288             written = ucs4_to_cns11643l2 (ch, buf, 2);                        \
 289             if (written != __UNKNOWN_10646_CHAR)                              \
 290               /* Yep, that worked.  */                                        \
 291               used = CNS11643_2_set;                                          \
 292             else                                                              \
 293               {                                                               \
 294                 /* Well, see whether we have to change the SO set.  */        \
 295                 if (used == GB2312_set)                                       \
 296                   written = ucs4_to_cns11643l1 (ch, buf, 2);                  \
 297                 else                                                          \
 298                   written = ucs4_to_gb2312 (ch, buf, 2);                      \
 299                                                                               \
 300                 if (__builtin_expect (written, 0) != __UNKNOWN_10646_CHAR)    \
 301                   /* Oh well, then switch SO.  */                             \
 302                   used = GB2312_set + CNS11643_1_set - used;                  \
 303                 else                                                          \
 304                   {                                                           \
 305                     UNICODE_TAG_HANDLER (ch, 4);                              \
 306                                                                               \
 307                     /* Even this does not work.  Error.  */                   \
 308                     STANDARD_TO_LOOP_ERR_HANDLER (4);                         \
 309                   }                                                           \
 310               }                                                               \
 311           }                                                                   \
 312         assert (written == 2);                                                \
 313                                                                               \
 314         /* See whether we have to emit an escape sequence.  */                \
 315         if (set != used)                                                      \
 316           {                                                                   \
 317             /* First see whether we announced that we use this                \
 318                character set.  */                                             \
 319             if ((ann & (16 << (used >> 3))) == 0)                             \
 320               {                                                               \
 321                 const char *escseq;                                           \
 322                                                                               \
 323                 if (__glibc_unlikely (outptr + 4 > outend))                   \
 324                   {                                                           \
 325                     result = __GCONV_FULL_OUTPUT;                             \
 326                     break;                                                    \
 327                   }                                                           \
 328                                                                               \
 329                 assert ((used >> 3) >= 1 && (used >> 3) <= 3);                \
 330                 escseq = ")A)G*H" + ((used >> 3) - 1) * 2;                    \
 331                 *outptr++ = ESC;                                              \
 332                 *outptr++ = '$';                                              \
 333                 *outptr++ = *escseq++;                                        \
 334                 *outptr++ = *escseq++;                                        \
 335                                                                               \
 336                 if (used == GB2312_set)                                       \
 337                   ann = (ann & CNS11643_2_ann) | GB2312_ann;                  \
 338                 else if (used == CNS11643_1_set)                              \
 339                   ann = (ann & CNS11643_2_ann) | CNS11643_1_ann;              \
 340                 else                                                          \
 341                   ann |= CNS11643_2_ann;                                      \
 342               }                                                               \
 343                                                                               \
 344             if (used == CNS11643_2_set)                                       \
 345               {                                                               \
 346                 if (__glibc_unlikely (outptr + 2 > outend))                   \
 347                   {                                                           \
 348                     result = __GCONV_FULL_OUTPUT;                             \
 349                     break;                                                    \
 350                   }                                                           \
 351                 *outptr++ = SS2_0;                                            \
 352                 *outptr++ = SS2_1;                                            \
 353               }                                                               \
 354             else                                                              \
 355               {                                                               \
 356                 /* We only have to emit something is currently ASCII is       \
 357                    selected.  Otherwise we are switching within the           \
 358                    SO charset.  */                                            \
 359                 if (set == ASCII_set)                                         \
 360                   {                                                           \
 361                     if (__glibc_unlikely (outptr + 1 > outend))               \
 362                       {                                                       \
 363                         result = __GCONV_FULL_OUTPUT;                         \
 364                         break;                                                \
 365                       }                                                       \
 366                     *outptr++ = SO;                                           \
 367                   }                                                           \
 368               }                                                               \
 369                                                                               \
 370             /* Always test the length here since we have used up all the      \
 371                guaranteed output buffer slots.  */                            \
 372             if (__glibc_unlikely (outptr + 2 > outend))                       \
 373               {                                                               \
 374                 result = __GCONV_FULL_OUTPUT;                                 \
 375                 break;                                                        \
 376               }                                                               \
 377           }                                                                   \
 378         else if (__glibc_unlikely (outptr + 2 > outend))                      \
 379           {                                                                   \
 380             result = __GCONV_FULL_OUTPUT;                                     \
 381             break;                                                            \
 382           }                                                                   \
 383                                                                               \
 384         *outptr++ = buf[0];                                                   \
 385         *outptr++ = buf[1];                                                   \
 386         set = used;                                                           \
 387       }                                                                       \
 388                                                                               \
 389     /* Now that we wrote the output increment the input pointer.  */          \
 390     inptr += 4;                                                               \
 391   }
 392 #define LOOP_NEED_FLAGS
 393 #define EXTRA_LOOP_DECLS        , int *setp
 394 #define INIT_PARAMS             int set = *setp & CURRENT_SEL_MASK; \
 395                                 int ann = *setp & CURRENT_ANN_MASK
 396 #define REINIT_PARAMS           do                                            \
 397                                   {                                           \
 398                                     set = *setp & CURRENT_SEL_MASK;           \
 399                                     ann = *setp & CURRENT_ANN_MASK;           \
 400                                   }                                           \
 401                                 while (0)
 402 #define UPDATE_PARAMS           *setp = set | ann
 403 #include <iconv/loop.c>
 404
 405
 406 /* Now define the toplevel functions.  */
 407 #include <iconv/skeleton.c>