tags/pcre-2.06/get.c

/*************************************************
*      Perl-Compatible Regular Expressions       *
*************************************************/

/*
This is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language. See
the file Tech.Notes for some information on the internals.

Written by: Philip Hazel <ph10@cam.ac.uk>

           Copyright (c) 1997-1999 University of Cambridge

-----------------------------------------------------------------------------
Permission is granted to anyone to use this software for any purpose on any
computer system, and to redistribute it freely, subject to the following
restrictions:

1. This software is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

2. The origin of this software must not be misrepresented, either by
   explicit claim or by omission.

3. Altered versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

4. If PCRE is embedded in any software that is released under the GNU
   General Purpose Licence (GPL), then the terms of that licence shall
   supersede any condition above with which it is incompatible.
-----------------------------------------------------------------------------
*/

/* This module contains some convenience functions for extracting substrings
from the subject string after a regex match has succeeded. The original idea
for these functions came from Scott Wimer <scottw@cgibuilder.com>. */


/* Include the internals header, which itself includes Standard C headers plus
the external pcre header. */

#include "internal.h"


/*************************************************
*      Copy captured string to given buffer      *
*************************************************/

/* This function copies a single captured substring into a given buffer.
Note that we use memcpy() rather than strncpy() in case there are binary zeros
in the string.

Arguments:
  subject        the subject string that was matched
  ovector        pointer to the offsets table
  stringcount    the number of substrings that were captured
                   (i.e. the yield of the pcre_exec call, unless
                   that was zero, in which case it should be 1/3
                   of the offset table size)
  stringnumber   the number of the required substring
  buffer         where to put the substring
  size           the size of the buffer

Returns:         if successful:
                   the length of the copied string, not including the zero
                   that is put on the end; can be zero
                 if not successful:
                   PCRE_ERROR_NOMEMORY (-6) buffer too small
                   PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
*/

int
pcre_copy_substring(const char *subject, int *ovector, int stringcount,
  int stringnumber, char *buffer, int size)
{
int yield;
if (stringnumber < 0 || stringnumber >= stringcount)
  return PCRE_ERROR_NOSUBSTRING;
stringnumber *= 2;
yield = ovector[stringnumber+1] - ovector[stringnumber];
if (size < yield + 1) return PCRE_ERROR_NOMEMORY;
memcpy(buffer, subject + ovector[stringnumber], yield);
buffer[yield] = 0;
return yield;
}


/*************************************************
*      Copy all captured strings to new store    *
*************************************************/

/* This function gets one chunk of store and builds a list of pointers and all
of the captured substrings in it. A NULL pointer is put on the end of the list.

Arguments:
  subject        the subject string that was matched
  ovector        pointer to the offsets table
  stringcount    the number of substrings that were captured
                   (i.e. the yield of the pcre_exec call, unless
                   that was zero, in which case it should be 1/3
                   of the offset table size)
  listptr        set to point to the list of pointers

Returns:         if successful: 0
                 if not successful:
                   PCRE_ERROR_NOMEMORY (-6) failed to get store
*/

int
pcre_get_substring_list(const char *subject, int *ovector, int stringcount,
  const char ***listptr)
{
int i;
int size = sizeof(char *);
int double_count = stringcount * 2;
char **stringlist;
char *p;

for (i = 0; i < double_count; i += 2)
  size += sizeof(char *) + ovector[i+1] - ovector[i] + 1;

stringlist = (char **)(pcre_malloc)(size);
if (stringlist == NULL) return PCRE_ERROR_NOMEMORY;

*listptr = (const char **)stringlist;
p = (char *)(stringlist + stringcount + 1);

for (i = 0; i < double_count; i += 2)
  {
  int len = ovector[i+1] - ovector[i];
  memcpy(p, subject + ovector[i], len);
  *stringlist++ = p;
  p += len;
  *p++ = 0;
  }

*stringlist = NULL;
return 0;
}


/*************************************************
*      Copy captured string to new store         *
*************************************************/

/* This function copies a single captured substring into a piece of new
store

Arguments:
  subject        the subject string that was matched
  ovector        pointer to the offsets table
  stringcount    the number of substrings that were captured
                   (i.e. the yield of the pcre_exec call, unless
                   that was zero, in which case it should be 1/3
                   of the offset table size)
  stringnumber   the number of the required substring
  stringptr      where to put a pointer to the substring

Returns:         if successful:
                   the length of the string, not including the zero that
                   is put on the end; can be zero
                 if not successful:
                   PCRE_ERROR_NOMEMORY (-6) failed to get store
                   PCRE_ERROR_NOSUBSTRING (-7) substring not present
*/

int
pcre_get_substring(const char *subject, int *ovector, int stringcount,
  int stringnumber, const char **stringptr)
{
int yield;
char *substring;
if (stringnumber < 0 || stringnumber >= stringcount)
  return PCRE_ERROR_NOSUBSTRING;
stringnumber *= 2;
yield = ovector[stringnumber+1] - ovector[stringnumber];
substring = (char *)(pcre_malloc)(yield + 1);
if (substring == NULL) return PCRE_ERROR_NOMEMORY;
memcpy(substring, subject + ovector[stringnumber], yield);
substring[yield] = 0;
*stringptr = substring;
return yield;
}

/* End of get.c */
1	nigel	29	/*************************************************
2			* Perl-Compatible Regular Expressions *
3			*************************************************/
4
5			/*
6			This is a library of functions to support regular expressions whose syntax
7			and semantics are as close as possible to those of the Perl 5 language. See
8			the file Tech.Notes for some information on the internals.
9
10			Written by: Philip Hazel <ph10@cam.ac.uk>
11
12			Copyright (c) 1997-1999 University of Cambridge
13
14			-----------------------------------------------------------------------------
15			Permission is granted to anyone to use this software for any purpose on any
16			computer system, and to redistribute it freely, subject to the following
17			restrictions:
18
19			1. This software is distributed in the hope that it will be useful,
20			but WITHOUT ANY WARRANTY; without even the implied warranty of
21			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22
23			2. The origin of this software must not be misrepresented, either by
24			explicit claim or by omission.
25
26			3. Altered versions must be plainly marked as such, and must not be
27			misrepresented as being the original software.
28
29			4. If PCRE is embedded in any software that is released under the GNU
30			General Purpose Licence (GPL), then the terms of that licence shall
31			supersede any condition above with which it is incompatible.
32			-----------------------------------------------------------------------------
33			*/
34
35			/* This module contains some convenience functions for extracting substrings
36			from the subject string after a regex match has succeeded. The original idea
37			for these functions came from Scott Wimer <scottw@cgibuilder.com>. */
38
39
40			/* Include the internals header, which itself includes Standard C headers plus
41			the external pcre header. */
42
43			#include "internal.h"
44
45
46
47			/*************************************************
48			* Copy captured string to given buffer *
49			*************************************************/
50
51			/* This function copies a single captured substring into a given buffer.
52			Note that we use memcpy() rather than strncpy() in case there are binary zeros
53			in the string.
54
55			Arguments:
56			subject the subject string that was matched
57			ovector pointer to the offsets table
58			stringcount the number of substrings that were captured
59			(i.e. the yield of the pcre_exec call, unless
60			that was zero, in which case it should be 1/3
61			of the offset table size)
62			stringnumber the number of the required substring
63			buffer where to put the substring
64			size the size of the buffer
65
66			Returns: if successful:
67			the length of the copied string, not including the zero
68			that is put on the end; can be zero
69			if not successful:
70			PCRE_ERROR_NOMEMORY (-6) buffer too small
71			PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
72			*/
73
74			int
75			pcre_copy_substring(const char subject, int ovector, int stringcount,
76			int stringnumber, char *buffer, int size)
77			{
78			int yield;
79			if (stringnumber < 0 \|\| stringnumber >= stringcount)
80			return PCRE_ERROR_NOSUBSTRING;
81			stringnumber *= 2;
82			yield = ovector[stringnumber+1] - ovector[stringnumber];
83			if (size < yield + 1) return PCRE_ERROR_NOMEMORY;
84			memcpy(buffer, subject + ovector[stringnumber], yield);
85			buffer[yield] = 0;
86			return yield;
87			}
88
89
90
91			/*************************************************
92			* Copy all captured strings to new store *
93			*************************************************/
94
95			/* This function gets one chunk of store and builds a list of pointers and all
96			of the captured substrings in it. A NULL pointer is put on the end of the list.
97
98			Arguments:
99			subject the subject string that was matched
100			ovector pointer to the offsets table
101			stringcount the number of substrings that were captured
102			(i.e. the yield of the pcre_exec call, unless
103			that was zero, in which case it should be 1/3
104			of the offset table size)
105			listptr set to point to the list of pointers
106
107			Returns: if successful: 0
108			if not successful:
109			PCRE_ERROR_NOMEMORY (-6) failed to get store
110			*/
111
112			int
113			pcre_get_substring_list(const char subject, int ovector, int stringcount,
114			const char ***listptr)
115			{
116			int i;
117			int size = sizeof(char *);
118			int double_count = stringcount * 2;
119			char **stringlist;
120			char *p;
121
122			for (i = 0; i < double_count; i += 2)
123			size += sizeof(char *) + ovector[i+1] - ovector[i] + 1;
124
125			stringlist = (char **)(pcre_malloc)(size);
126			if (stringlist == NULL) return PCRE_ERROR_NOMEMORY;
127
128			listptr = (const char *)stringlist;
129			p = (char *)(stringlist + stringcount + 1);
130
131			for (i = 0; i < double_count; i += 2)
132			{
133			int len = ovector[i+1] - ovector[i];
134			memcpy(p, subject + ovector[i], len);
135			*stringlist++ = p;
136			p += len;
137			*p++ = 0;
138			}
139
140			*stringlist = NULL;
141			return 0;
142			}
143
144
145
146			/*************************************************
147			* Copy captured string to new store *
148			*************************************************/
149
150			/* This function copies a single captured substring into a piece of new
151			store
152
153			Arguments:
154			subject the subject string that was matched
155			ovector pointer to the offsets table
156			stringcount the number of substrings that were captured
157			(i.e. the yield of the pcre_exec call, unless
158			that was zero, in which case it should be 1/3
159			of the offset table size)
160			stringnumber the number of the required substring
161			stringptr where to put a pointer to the substring
162
163			Returns: if successful:
164			the length of the string, not including the zero that
165			is put on the end; can be zero
166			if not successful:
167			PCRE_ERROR_NOMEMORY (-6) failed to get store
168			PCRE_ERROR_NOSUBSTRING (-7) substring not present
169			*/
170
171			int
172			pcre_get_substring(const char subject, int ovector, int stringcount,
173			int stringnumber, const char **stringptr)
174			{
175			int yield;
176			char *substring;
177			if (stringnumber < 0 \|\| stringnumber >= stringcount)
178			return PCRE_ERROR_NOSUBSTRING;
179			stringnumber *= 2;
180			yield = ovector[stringnumber+1] - ovector[stringnumber];
181			substring = (char *)(pcre_malloc)(yield + 1);
182			if (substring == NULL) return PCRE_ERROR_NOMEMORY;
183			memcpy(substring, subject + ovector[stringnumber], yield);
184			substring[yield] = 0;
185			*stringptr = substring;
186			return yield;
187			}
188
189			/* End of get.c */