pcre  8.44
About: The PCRE library implements Perl compatible regular expression pattern matching.
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pcre_maketables.c
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1 
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 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 
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 PUBL(malloc)(), but when
63 compiled inside dftables, use malloc().
64 
65 Arguments: none
66 Returns: pointer to the contiguous block of data
67 */
68 
69 #if defined COMPILE_PCRE8
70 const unsigned char *
72 #elif defined COMPILE_PCRE16
73 const unsigned char *
74 pcre16_maketables(void)
75 #elif defined COMPILE_PCRE32
76 const unsigned char *
77 pcre32_maketables(void)
78 #endif
79 {
80 unsigned char *yield, *p;
81 int i;
82 
83 #ifndef DFTABLES
84 yield = (unsigned char*)(PUBL(malloc))(tables_length);
85 #else
86 yield = (unsigned char*)malloc(tables_length);
87 #endif
88 
89 if (yield == NULL) return NULL;
90 p = yield;
91 
92 /* First comes the lower casing table */
93 
94 for (i = 0; i < 256; i++) *p++ = tolower(i);
95 
96 /* Next the case-flipping table */
97 
98 for (i = 0; i < 256; i++) *p++ = islower(i)? toupper(i) : tolower(i);
99 
100 /* Then the character class tables. Don't try to be clever and save effort on
101 exclusive ones - in some locales things may be different.
102 
103 Note that the table for "space" includes everything "isspace" gives, including
104 VT in the default locale. This makes it work for the POSIX class [:space:].
105 From release 8.34 is is also correct for Perl space, because Perl added VT at
106 release 5.18.
107 
108 Note also that it is possible for a character to be alnum or alpha without
109 being lower or upper, such as "male and female ordinals" (\xAA and \xBA) in the
110 fr_FR locale (at least under Debian Linux's locales as of 12/2005). So we must
111 test for alnum specially. */
112 
113 memset(p, 0, cbit_length);
114 for (i = 0; i < 256; i++)
115  {
116  if (isdigit(i)) p[cbit_digit + i/8] |= 1 << (i&7);
117  if (isupper(i)) p[cbit_upper + i/8] |= 1 << (i&7);
118  if (islower(i)) p[cbit_lower + i/8] |= 1 << (i&7);
119  if (isalnum(i)) p[cbit_word + i/8] |= 1 << (i&7);
120  if (i == '_') p[cbit_word + i/8] |= 1 << (i&7);
121  if (isspace(i)) p[cbit_space + i/8] |= 1 << (i&7);
122  if (isxdigit(i))p[cbit_xdigit + i/8] |= 1 << (i&7);
123  if (isgraph(i)) p[cbit_graph + i/8] |= 1 << (i&7);
124  if (isprint(i)) p[cbit_print + i/8] |= 1 << (i&7);
125  if (ispunct(i)) p[cbit_punct + i/8] |= 1 << (i&7);
126  if (iscntrl(i)) p[cbit_cntrl + i/8] |= 1 << (i&7);
127  }
128 p += cbit_length;
129 
130 /* Finally, the character type table. In this, we used to exclude VT from the
131 white space chars, because Perl didn't recognize it as such for \s and for
132 comments within regexes. However, Perl changed at release 5.18, so PCRE changed
133 at release 8.34. */
134 
135 for (i = 0; i < 256; i++)
136  {
137  int x = 0;
138  if (isspace(i)) x += ctype_space;
139  if (isalpha(i)) x += ctype_letter;
140  if (isdigit(i)) x += ctype_digit;
141  if (isxdigit(i)) x += ctype_xdigit;
142  if (isalnum(i) || i == '_') x += ctype_word;
143 
144  /* Note: strchr includes the terminating zero in the characters it considers.
145  In this instance, that is ok because we want binary zero to be flagged as a
146  meta-character, which in this sense is any character that terminates a run
147  of data characters. */
148 
149  if (strchr("\\*+?{^.$|()[", i) != 0) x += ctype_meta;
150  *p++ = x;
151  }
152 
153 return yield;
154 }
155 
156 /* End of pcre_maketables.c */
ctype_word
#define ctype_word
Definition: pcre_internal.h:2590
ctype_meta
#define ctype_meta
Definition: pcre_internal.h:2591
ctype_space
#define ctype_space
Definition: pcre_internal.h:2586
cbit_punct
#define cbit_punct
Definition: pcre_internal.h:2604
PUBL
#define PUBL(name)
Definition: pcre_internal.h:2621
cbit_graph
#define cbit_graph
Definition: pcre_internal.h:2602
ctype_letter
#define ctype_letter
Definition: pcre_internal.h:2587
ctype_digit
#define ctype_digit
Definition: pcre_internal.h:2588
cbit_word
#define cbit_word
Definition: pcre_internal.h:2601
cbit_length
#define cbit_length
Definition: pcre_internal.h:2606
pcre_maketables
const unsigned char * pcre_maketables(void)
Definition: pcre_maketables.c:71
cbit_print
#define cbit_print
Definition: pcre_internal.h:2603
cbit_digit
#define cbit_digit
Definition: pcre_internal.h:2598
cbit_lower
#define cbit_lower
Definition: pcre_internal.h:2600
cbit_cntrl
#define cbit_cntrl
Definition: pcre_internal.h:2605
ctype_xdigit
#define ctype_xdigit
Definition: pcre_internal.h:2589
pcre_internal.h
cbit_upper
#define cbit_upper
Definition: pcre_internal.h:2599
cbit_xdigit
#define cbit_xdigit
Definition: pcre_internal.h:2597
cbit_space
#define cbit_space
Definition: pcre_internal.h:2596
tables_length
#define tables_length
Definition: pcre_internal.h:2615