tools/pcre/pcre_maketables.c
author David Anderson <dvander@alliedmods.net>
Tue Jul 28 17:51:34 2009 -0400 (2009-07-28)
changeset 2762 d2d467bf1b5a
child 3831 babd0eee3c5e
permissions -rw-r--r--
Check-in of pcre-7.9 source code and win32 static lib (bug 3923).
     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) 1997-2008 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 the external function pcre_maketables(), which builds
    42 character tables for PCRE in the current locale. The file is compiled on its
    43 own as part of the PCRE library. However, it is also included in the
    44 compilation of dftables.c, in which case the macro DFTABLES is defined. */
    45 
    46 
    47 #ifndef DFTABLES
    48 #  ifdef HAVE_CONFIG_H
    49 #  include "config.h"
    50 #  endif
    51 #  include "pcre_internal.h"
    52 #endif
    53 
    54 
    55 /*************************************************
    56 *           Create PCRE character tables         *
    57 *************************************************/
    58 
    59 /* This function builds a set of character tables for use by PCRE and returns
    60 a pointer to them. They are build using the ctype functions, and consequently
    61 their contents will depend upon the current locale setting. When compiled as
    62 part of the library, the store is obtained via pcre_malloc(), but when compiled
    63 inside dftables, use malloc().
    64 
    65 Arguments:   none
    66 Returns:     pointer to the contiguous block of data
    67 */
    68 
    69 const unsigned char *
    70 pcre_maketables(void)
    71 {
    72 unsigned char *yield, *p;
    73 int i;
    74 
    75 #ifndef DFTABLES
    76 yield = (unsigned char*)(pcre_malloc)(tables_length);
    77 #else
    78 yield = (unsigned char*)malloc(tables_length);
    79 #endif
    80 
    81 if (yield == NULL) return NULL;
    82 p = yield;
    83 
    84 /* First comes the lower casing table */
    85 
    86 for (i = 0; i < 256; i++) *p++ = tolower(i);
    87 
    88 /* Next the case-flipping table */
    89 
    90 for (i = 0; i < 256; i++) *p++ = islower(i)? toupper(i) : tolower(i);
    91 
    92 /* Then the character class tables. Don't try to be clever and save effort on
    93 exclusive ones - in some locales things may be different. Note that the table
    94 for "space" includes everything "isspace" gives, including VT in the default
    95 locale. This makes it work for the POSIX class [:space:]. Note also that it is
    96 possible for a character to be alnum or alpha without being lower or upper,
    97 such as "male and female ordinals" (\xAA and \xBA) in the fr_FR locale (at
    98 least under Debian Linux's locales as of 12/2005). So we must test for alnum
    99 specially. */
   100 
   101 memset(p, 0, cbit_length);
   102 for (i = 0; i < 256; i++)
   103   {
   104   if (isdigit(i)) p[cbit_digit  + i/8] |= 1 << (i&7);
   105   if (isupper(i)) p[cbit_upper  + i/8] |= 1 << (i&7);
   106   if (islower(i)) p[cbit_lower  + i/8] |= 1 << (i&7);
   107   if (isalnum(i)) p[cbit_word   + i/8] |= 1 << (i&7);
   108   if (i == '_')   p[cbit_word   + i/8] |= 1 << (i&7);
   109   if (isspace(i)) p[cbit_space  + i/8] |= 1 << (i&7);
   110   if (isxdigit(i))p[cbit_xdigit + i/8] |= 1 << (i&7);
   111   if (isgraph(i)) p[cbit_graph  + i/8] |= 1 << (i&7);
   112   if (isprint(i)) p[cbit_print  + i/8] |= 1 << (i&7);
   113   if (ispunct(i)) p[cbit_punct  + i/8] |= 1 << (i&7);
   114   if (iscntrl(i)) p[cbit_cntrl  + i/8] |= 1 << (i&7);
   115   }
   116 p += cbit_length;
   117 
   118 /* Finally, the character type table. In this, we exclude VT from the white
   119 space chars, because Perl doesn't recognize it as such for \s and for comments
   120 within regexes. */
   121 
   122 for (i = 0; i < 256; i++)
   123   {
   124   int x = 0;
   125   if (i != 0x0b && isspace(i)) x += ctype_space;
   126   if (isalpha(i)) x += ctype_letter;
   127   if (isdigit(i)) x += ctype_digit;
   128   if (isxdigit(i)) x += ctype_xdigit;
   129   if (isalnum(i) || i == '_') x += ctype_word;
   130 
   131   /* Note: strchr includes the terminating zero in the characters it considers.
   132   In this instance, that is ok because we want binary zero to be flagged as a
   133   meta-character, which in this sense is any character that terminates a run
   134   of data characters. */
   135 
   136   if (strchr("\\*+?{^.$|()[", i) != 0) x += ctype_meta;
   137   *p++ = x;
   138   }
   139 
   140 return yield;
   141 }
   142 
   143 /* End of pcre_maketables.c */