glib/pcre/pcre_byte_order.c

   1 /*************************************************
   2 *      Perl-Compatible Regular Expressions       *
   3 *************************************************/
   4
   5 /* PCRE is a library of functions to support regular expressions whose syntax
   6 and semantics are as close as possible to those of the Perl 5 language.
   7
   8                        Written by Philip Hazel
   9            Copyright (c) 1997-2012 University of Cambridge
  10
  11 -----------------------------------------------------------------------------
  12 Redistribution and use in source and binary forms, with or without
  13 modification, are permitted provided that the following conditions are met:
  14
  15     * Redistributions of source code must retain the above copyright notice,
  16       this list of conditions and the following disclaimer.
  17
  18     * Redistributions in binary form must reproduce the above copyright
  19       notice, this list of conditions and the following disclaimer in the
  20       documentation and/or other materials provided with the distribution.
  21
  22     * Neither the name of the University of Cambridge nor the names of its
  23       contributors may be used to endorse or promote products derived from
  24       this software without specific prior written permission.
  25
  26 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  27 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  30 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  31 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  32 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  33 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  34 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36 POSSIBILITY OF SUCH DAMAGE.
  37 -----------------------------------------------------------------------------
  38 */
  39
  40
  41 /* This module contains an internal function that tests a compiled pattern to
  42 see if it was compiled with the opposite endianness. If so, it uses an
  43 auxiliary local function to flip the appropriate bytes. */
  44
  45
  46 #ifdef HAVE_CONFIG_H
  47 #include "config.h"
  48 #endif
  49
  50 #include "pcre_internal.h"
  51
  52
  53 /*************************************************
  54 *             Swap byte functions                *
  55 *************************************************/
  56
  57 /* The following functions swap the bytes of a pcre_uint16
  58 and pcre_uint32 value.
  59
  60 Arguments:
  61   value        any number
  62
  63 Returns:       the byte swapped value
  64 */
  65
  66 static pcre_uint32
  67 swap_uint32(pcre_uint32 value)
  68 {
  69 return ((value & 0x000000ff) << 24) |
  70        ((value & 0x0000ff00) <<  8) |
  71        ((value & 0x00ff0000) >>  8) |
  72        (value >> 24);
  73 }
  74
  75 static pcre_uint16
  76 swap_uint16(pcre_uint16 value)
  77 {
  78 return (value >> 8) | (value << 8);
  79 }
  80
  81
  82 /*************************************************
  83 *       Test for a byte-flipped compiled regex   *
  84 *************************************************/
  85
  86 /* This function swaps the bytes of a compiled pattern usually
  87 loaded form the disk. It also sets the tables pointer, which
  88 is likely an invalid pointer after reload.
  89
  90 Arguments:
  91   argument_re     points to the compiled expression
  92   extra_data      points to extra data or is NULL
  93   tables          points to the character tables or NULL
  94
  95 Returns:          0 if the swap is successful, negative on error
  96 */
  97
  98 #ifdef COMPILE_PCRE8
  99 PCRE_EXP_DECL int pcre_pattern_to_host_byte_order(pcre *argument_re,
 100   pcre_extra *extra_data, const unsigned char *tables)
 101 #else
 102 PCRE_EXP_DECL int pcre16_pattern_to_host_byte_order(pcre16 *argument_re,
 103   pcre16_extra *extra_data, const unsigned char *tables)
 104 #endif
 105 {
 106 REAL_PCRE *re = (REAL_PCRE *)argument_re;
 107 pcre_study_data *study;
 108 #ifndef COMPILE_PCRE8
 109 pcre_uchar *ptr;
 110 int length;
 111 #ifdef SUPPORT_UTF
 112 BOOL utf;
 113 BOOL utf16_char;
 114 #endif /* SUPPORT_UTF */
 115 #endif /* !COMPILE_PCRE8 */
 116
 117 if (re == NULL) return PCRE_ERROR_NULL;
 118 if (re->magic_number == MAGIC_NUMBER)
 119   {
 120   if ((re->flags & PCRE_MODE) == 0) return PCRE_ERROR_BADMODE;
 121   re->tables = tables;
 122   return 0;
 123   }
 124
 125 if (re->magic_number != REVERSED_MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC;
 126 if ((swap_uint16(re->flags) & PCRE_MODE) == 0) return PCRE_ERROR_BADMODE;
 127
 128 re->magic_number = MAGIC_NUMBER;
 129 re->size = swap_uint32(re->size);
 130 re->options = swap_uint32(re->options);
 131 re->flags = swap_uint16(re->flags);
 132 re->top_bracket = swap_uint16(re->top_bracket);
 133 re->top_backref = swap_uint16(re->top_backref);
 134 re->first_char = swap_uint16(re->first_char);
 135 re->req_char = swap_uint16(re->req_char);
 136 re->name_table_offset = swap_uint16(re->name_table_offset);
 137 re->name_entry_size = swap_uint16(re->name_entry_size);
 138 re->name_count = swap_uint16(re->name_count);
 139 re->ref_count = swap_uint16(re->ref_count);
 140 re->tables = tables;
 141
 142 if (extra_data != NULL && (extra_data->flags & PCRE_EXTRA_STUDY_DATA) != 0)
 143   {
 144   study = (pcre_study_data *)extra_data->study_data;
 145   study->size = swap_uint32(study->size);
 146   study->flags = swap_uint32(study->flags);
 147   study->minlength = swap_uint32(study->minlength);
 148   }
 149
 150 #ifndef COMPILE_PCRE8
 151 ptr = (pcre_uchar *)re + re->name_table_offset;
 152 length = re->name_count * re->name_entry_size;
 153 #ifdef SUPPORT_UTF
 154 utf = (re->options & PCRE_UTF16) != 0;
 155 utf16_char = FALSE;
 156 #endif
 157
 158 while(TRUE)
 159   {
 160   /* Swap previous characters. */
 161   while (length-- > 0)
 162     {
 163     *ptr = swap_uint16(*ptr);
 164     ptr++;
 165     }
 166 #ifdef SUPPORT_UTF
 167   if (utf16_char)
 168     {
 169     if (HAS_EXTRALEN(ptr[-1]))
 170       {
 171       /* We know that there is only one extra character in UTF-16. */
 172       *ptr = swap_uint16(*ptr);
 173       ptr++;
 174       }
 175     }
 176   utf16_char = FALSE;
 177 #endif /* SUPPORT_UTF */
 178
 179   /* Get next opcode. */
 180   length = 0;
 181   *ptr = swap_uint16(*ptr);
 182   switch (*ptr)
 183     {
 184     case OP_END:
 185     return 0;
 186
 187 #ifdef SUPPORT_UTF
 188     case OP_CHAR:
 189     case OP_CHARI:
 190     case OP_NOT:
 191     case OP_NOTI:
 192     case OP_STAR:
 193     case OP_MINSTAR:
 194     case OP_PLUS:
 195     case OP_MINPLUS:
 196     case OP_QUERY:
 197     case OP_MINQUERY:
 198     case OP_UPTO:
 199     case OP_MINUPTO:
 200     case OP_EXACT:
 201     case OP_POSSTAR:
 202     case OP_POSPLUS:
 203     case OP_POSQUERY:
 204     case OP_POSUPTO:
 205     case OP_STARI:
 206     case OP_MINSTARI:
 207     case OP_PLUSI:
 208     case OP_MINPLUSI:
 209     case OP_QUERYI:
 210     case OP_MINQUERYI:
 211     case OP_UPTOI:
 212     case OP_MINUPTOI:
 213     case OP_EXACTI:
 214     case OP_POSSTARI:
 215     case OP_POSPLUSI:
 216     case OP_POSQUERYI:
 217     case OP_POSUPTOI:
 218     case OP_NOTSTAR:
 219     case OP_NOTMINSTAR:
 220     case OP_NOTPLUS:
 221     case OP_NOTMINPLUS:
 222     case OP_NOTQUERY:
 223     case OP_NOTMINQUERY:
 224     case OP_NOTUPTO:
 225     case OP_NOTMINUPTO:
 226     case OP_NOTEXACT:
 227     case OP_NOTPOSSTAR:
 228     case OP_NOTPOSPLUS:
 229     case OP_NOTPOSQUERY:
 230     case OP_NOTPOSUPTO:
 231     case OP_NOTSTARI:
 232     case OP_NOTMINSTARI:
 233     case OP_NOTPLUSI:
 234     case OP_NOTMINPLUSI:
 235     case OP_NOTQUERYI:
 236     case OP_NOTMINQUERYI:
 237     case OP_NOTUPTOI:
 238     case OP_NOTMINUPTOI:
 239     case OP_NOTEXACTI:
 240     case OP_NOTPOSSTARI:
 241     case OP_NOTPOSPLUSI:
 242     case OP_NOTPOSQUERYI:
 243     case OP_NOTPOSUPTOI:
 244     if (utf) utf16_char = TRUE;
 245 #endif
 246     /* Fall through. */
 247
 248     default:
 249     length = PRIV(OP_lengths)[*ptr] - 1;
 250     break;
 251
 252     case OP_CLASS:
 253     case OP_NCLASS:
 254     /* Skip the character bit map. */
 255     ptr += 32/sizeof(pcre_uchar);
 256     length = 0;
 257     break;
 258
 259     case OP_XCLASS:
 260     /* Reverse the size of the XCLASS instance. */
 261     ptr++;
 262     *ptr = swap_uint16(*ptr);
 263     if (LINK_SIZE > 1)
 264       {
 265       /* LINK_SIZE can be 1 or 2 in 16 bit mode. */
 266       ptr++;
 267       *ptr = swap_uint16(*ptr);
 268       }
 269     ptr++;
 270     length = (GET(ptr, -LINK_SIZE)) - (1 + LINK_SIZE + 1);
 271     *ptr = swap_uint16(*ptr);
 272     if ((*ptr & XCL_MAP) != 0)
 273       {
 274       /* Skip the character bit map. */
 275       ptr += 32/sizeof(pcre_uchar);
 276       length -= 32/sizeof(pcre_uchar);
 277       }
 278     break;
 279     }
 280   ptr++;
 281   }
 282 /* Control should never reach here in 16 bit mode. */
 283 #endif /* !COMPILE_PCRE8 */
 284
 285 return 0;
 286 }
 287
 288 /* End of pcre_byte_order.c */