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Member "tin-2.4.1/pcre/pcre_maketables.c" (28 Aug 2013, 5462 Bytes) of archive /linux/misc/tin-2.4.1.tar.gz:


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    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) 1997-2006 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 #include "pcre_internal.h"
   49 #endif
   50 
   51 
   52 /*************************************************
   53 *           Create PCRE character tables         *
   54 *************************************************/
   55 
   56 /* This function builds a set of character tables for use by PCRE and returns
   57 a pointer to them. They are build using the ctype functions, and consequently
   58 their contents will depend upon the current locale setting. When compiled as
   59 part of the library, the store is obtained via pcre_malloc(), but when compiled
   60 inside dftables, use malloc().
   61 
   62 Arguments:   none
   63 Returns:     pointer to the contiguous block of data
   64 */
   65 
   66 const unsigned char *
   67 pcre_maketables(void)
   68 {
   69 unsigned char *yield, *p;
   70 int i;
   71 
   72 #ifndef DFTABLES
   73 yield = (unsigned char*)(pcre_malloc)(tables_length);
   74 #else
   75 yield = (unsigned char*)malloc(tables_length);
   76 #endif
   77 
   78 if (yield == NULL) return NULL;
   79 p = yield;
   80 
   81 /* First comes the lower casing table */
   82 
   83 for (i = 0; i < 256; i++) *p++ = tolower(i);
   84 
   85 /* Next the case-flipping table */
   86 
   87 for (i = 0; i < 256; i++) *p++ = islower(i)? toupper(i) : tolower(i);
   88 
   89 /* Then the character class tables. Don't try to be clever and save effort on
   90 exclusive ones - in some locales things may be different. Note that the table
   91 for "space" includes everything "isspace" gives, including VT in the default
   92 locale. This makes it work for the POSIX class [:space:]. Note also that it is
   93 possible for a character to be alnum or alpha without being lower or upper,
   94 such as "male and female ordinals" (\xAA and \xBA) in the fr_FR locale (at
   95 least under Debian Linux's locales as of 12/2005). So we must test for alnum
   96 specially. */
   97 
   98 memset(p, 0, cbit_length);
   99 for (i = 0; i < 256; i++)
  100   {
  101   if (isdigit(i)) p[cbit_digit  + i/8] |= 1 << (i&7);
  102   if (isupper(i)) p[cbit_upper  + i/8] |= 1 << (i&7);
  103   if (islower(i)) p[cbit_lower  + i/8] |= 1 << (i&7);
  104   if (isalnum(i)) p[cbit_word   + i/8] |= 1 << (i&7);
  105   if (i == '_')   p[cbit_word   + i/8] |= 1 << (i&7);
  106   if (isspace(i)) p[cbit_space  + i/8] |= 1 << (i&7);
  107   if (isxdigit(i))p[cbit_xdigit + i/8] |= 1 << (i&7);
  108   if (isgraph(i)) p[cbit_graph  + i/8] |= 1 << (i&7);
  109   if (isprint(i)) p[cbit_print  + i/8] |= 1 << (i&7);
  110   if (ispunct(i)) p[cbit_punct  + i/8] |= 1 << (i&7);
  111   if (iscntrl(i)) p[cbit_cntrl  + i/8] |= 1 << (i&7);
  112   }
  113 p += cbit_length;
  114 
  115 /* Finally, the character type table. In this, we exclude VT from the white
  116 space chars, because Perl doesn't recognize it as such for \s and for comments
  117 within regexes. */
  118 
  119 for (i = 0; i < 256; i++)
  120   {
  121   int x = 0;
  122   if (i != 0x0b && isspace(i)) x += ctype_space;
  123   if (isalpha(i)) x += ctype_letter;
  124   if (isdigit(i)) x += ctype_digit;
  125   if (isxdigit(i)) x += ctype_xdigit;
  126   if (isalnum(i) || i == '_') x += ctype_word;
  127 
  128   /* Note: strchr includes the terminating zero in the characters it considers.
  129   In this instance, that is ok because we want binary zero to be flagged as a
  130   meta-character, which in this sense is any character that terminates a run
  131   of data characters. */
  132 
  133   if (strchr("\\*+?{^.$|()[", i) != 0) x += ctype_meta;
  134   *p++ = x;
  135   }
  136 
  137 return yield;
  138 }
  139 
  140 /* End of pcre_maketables.c */