tags/pcre-5.0/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) 1997-2003 University of Cambridge

-----------------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

    * Neither the name of the University of Cambridge nor the names of its
      contributors may be used to endorse or promote products derived from
      this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
-----------------------------------------------------------------------------
*/

/* 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. */


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

#include "internal.h"


/*************************************************
*           Find number for named string         *
*************************************************/

/* This function is used by the two extraction functions below, as well
as being generally available.

Arguments:
  code        the compiled regex
  stringname  the name whose number is required

Returns:      the number of the named parentheses, or a negative number
                (PCRE_ERROR_NOSUBSTRING) if not found
*/

int
pcre_get_stringnumber(const pcre *code, const char *stringname)
{
int rc;
int entrysize;
int top, bot;
uschar *nametable;

if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMECOUNT, &top)) != 0)
  return rc;
if (top <= 0) return PCRE_ERROR_NOSUBSTRING;

if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMEENTRYSIZE, &entrysize)) != 0)
  return rc;
if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMETABLE, &nametable)) != 0)
  return rc;

bot = 0;
while (top > bot)
  {
  int mid = (top + bot) / 2;
  uschar *entry = nametable + entrysize*mid;
  int c = strcmp(stringname, (char *)(entry + 2));
  if (c == 0) return (entry[0] << 8) + entry[1];
  if (c > 0) bot = mid + 1; else top = mid;
  }

return PCRE_ERROR_NOSUBSTRING;
}


/*************************************************
*      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 named captured string to given buffer   *
*************************************************/

/* This function copies a single captured substring into a given buffer,
identifying it by name.

Arguments:
  code           the compiled regex
  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)
  stringname     the name 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_named_substring(const pcre *code, const char *subject, int *ovector,
  int stringcount, const char *stringname, char *buffer, int size)
{
int n = pcre_get_stringnumber(code, stringname);
if (n <= 0) return n;
return pcre_copy_substring(subject, ovector, stringcount, n, buffer, size);
}


/*************************************************
*      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;
}


/*************************************************
*   Free store obtained by get_substring_list    *
*************************************************/

/* This function exists for the benefit of people calling PCRE from non-C
programs that can call its functions, but not free() or (pcre_free)() directly.

Argument:   the result of a previous pcre_get_substring_list()
Returns:    nothing
*/

void
pcre_free_substring_list(const char **pointer)
{
(pcre_free)((void *)pointer);
}


/*************************************************
*      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;
}


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

/* This function copies a single captured substring, identified by name, into
new store.

Arguments:
  code           the compiled regex
  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)
  stringname     the name of the required substring
  stringptr      where to put the pointer

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) couldn't get memory
                   PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
*/

int
pcre_get_named_substring(const pcre *code, const char *subject, int *ovector,
  int stringcount, const char *stringname, const char **stringptr)
{
int n = pcre_get_stringnumber(code, stringname);
if (n <= 0) return n;
return pcre_get_substring(subject, ovector, stringcount, n, stringptr);
}


/*************************************************
*       Free store obtained by get_substring     *
*************************************************/

/* This function exists for the benefit of people calling PCRE from non-C
programs that can call its functions, but not free() or (pcre_free)() directly.

Argument:   the result of a previous pcre_get_substring()
Returns:    nothing
*/

void
pcre_free_substring(const char *pointer)
{
(pcre_free)((void *)pointer);
}

/* End of get.c */
1	/*************************************************
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) 1997-2003 University of Cambridge
13
14	-----------------------------------------------------------------------------
15	Redistribution and use in source and binary forms, with or without
16	modification, are permitted provided that the following conditions are met:
17
18	* Redistributions of source code must retain the above copyright notice,
19	this list of conditions and the following disclaimer.
20
21	* Redistributions in binary form must reproduce the above copyright
22	notice, this list of conditions and the following disclaimer in the
23	documentation and/or other materials provided with the distribution.
24
25	* Neither the name of the University of Cambridge nor the names of its
26	contributors may be used to endorse or promote products derived from
27	this software without specific prior written permission.
28
29	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
30	AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31	IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32	ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
33	LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
34	CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
35	SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
36	INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
37	CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38	ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
39	POSSIBILITY OF SUCH DAMAGE.
40	-----------------------------------------------------------------------------
41	*/
42
43	/* This module contains some convenience functions for extracting substrings
44	from the subject string after a regex match has succeeded. The original idea
45	for these functions came from Scott Wimer. */
46
47
48	/* Include the internals header, which itself includes Standard C headers plus
49	the external pcre header. */
50
51	#include "internal.h"
52
53
54	/*************************************************
55	* Find number for named string *
56	*************************************************/
57
58	/* This function is used by the two extraction functions below, as well
59	as being generally available.
60
61	Arguments:
62	code the compiled regex
63	stringname the name whose number is required
64
65	Returns: the number of the named parentheses, or a negative number
66	(PCRE_ERROR_NOSUBSTRING) if not found
67	*/
68
69	int
70	pcre_get_stringnumber(const pcre code, const char stringname)
71	{
72	int rc;
73	int entrysize;
74	int top, bot;
75	uschar *nametable;
76
77	if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMECOUNT, &top)) != 0)
78	return rc;
79	if (top <= 0) return PCRE_ERROR_NOSUBSTRING;
80
81	if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMEENTRYSIZE, &entrysize)) != 0)
82	return rc;
83	if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMETABLE, &nametable)) != 0)
84	return rc;
85
86	bot = 0;
87	while (top > bot)
88	{
89	int mid = (top + bot) / 2;
90	uschar entry = nametable + entrysizemid;
91	int c = strcmp(stringname, (char *)(entry + 2));
92	if (c == 0) return (entry[0] << 8) + entry[1];
93	if (c > 0) bot = mid + 1; else top = mid;
94	}
95
96	return PCRE_ERROR_NOSUBSTRING;
97	}
98
99
100
101	/*************************************************
102	* Copy captured string to given buffer *
103	*************************************************/
104
105	/* This function copies a single captured substring into a given buffer.
106	Note that we use memcpy() rather than strncpy() in case there are binary zeros
107	in the string.
108
109	Arguments:
110	subject the subject string that was matched
111	ovector pointer to the offsets table
112	stringcount the number of substrings that were captured
113	(i.e. the yield of the pcre_exec call, unless
114	that was zero, in which case it should be 1/3
115	of the offset table size)
116	stringnumber the number of the required substring
117	buffer where to put the substring
118	size the size of the buffer
119
120	Returns: if successful:
121	the length of the copied string, not including the zero
122	that is put on the end; can be zero
123	if not successful:
124	PCRE_ERROR_NOMEMORY (-6) buffer too small
125	PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
126	*/
127
128	int
129	pcre_copy_substring(const char subject, int ovector, int stringcount,
130	int stringnumber, char *buffer, int size)
131	{
132	int yield;
133	if (stringnumber < 0 \|\| stringnumber >= stringcount)
134	return PCRE_ERROR_NOSUBSTRING;
135	stringnumber *= 2;
136	yield = ovector[stringnumber+1] - ovector[stringnumber];
137	if (size < yield + 1) return PCRE_ERROR_NOMEMORY;
138	memcpy(buffer, subject + ovector[stringnumber], yield);
139	buffer[yield] = 0;
140	return yield;
141	}
142
143
144
145	/*************************************************
146	* Copy named captured string to given buffer *
147	*************************************************/
148
149	/* This function copies a single captured substring into a given buffer,
150	identifying it by name.
151
152	Arguments:
153	code the compiled regex
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	stringname the name of the required substring
161	buffer where to put the substring
162	size the size of the buffer
163
164	Returns: if successful:
165	the length of the copied string, not including the zero
166	that is put on the end; can be zero
167	if not successful:
168	PCRE_ERROR_NOMEMORY (-6) buffer too small
169	PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
170	*/
171
172	int
173	pcre_copy_named_substring(const pcre code, const char subject, int *ovector,
174	int stringcount, const char stringname, char buffer, int size)
175	{
176	int n = pcre_get_stringnumber(code, stringname);
177	if (n <= 0) return n;
178	return pcre_copy_substring(subject, ovector, stringcount, n, buffer, size);
179	}
180
181
182
183	/*************************************************
184	* Copy all captured strings to new store *
185	*************************************************/
186
187	/* This function gets one chunk of store and builds a list of pointers and all
188	of the captured substrings in it. A NULL pointer is put on the end of the list.
189
190	Arguments:
191	subject the subject string that was matched
192	ovector pointer to the offsets table
193	stringcount the number of substrings that were captured
194	(i.e. the yield of the pcre_exec call, unless
195	that was zero, in which case it should be 1/3
196	of the offset table size)
197	listptr set to point to the list of pointers
198
199	Returns: if successful: 0
200	if not successful:
201	PCRE_ERROR_NOMEMORY (-6) failed to get store
202	*/
203
204	int
205	pcre_get_substring_list(const char subject, int ovector, int stringcount,
206	const char ***listptr)
207	{
208	int i;
209	int size = sizeof(char *);
210	int double_count = stringcount * 2;
211	char **stringlist;
212	char *p;
213
214	for (i = 0; i < double_count; i += 2)
215	size += sizeof(char *) + ovector[i+1] - ovector[i] + 1;
216
217	stringlist = (char **)(pcre_malloc)(size);
218	if (stringlist == NULL) return PCRE_ERROR_NOMEMORY;
219
220	listptr = (const char *)stringlist;
221	p = (char *)(stringlist + stringcount + 1);
222
223	for (i = 0; i < double_count; i += 2)
224	{
225	int len = ovector[i+1] - ovector[i];
226	memcpy(p, subject + ovector[i], len);
227	*stringlist++ = p;
228	p += len;
229	*p++ = 0;
230	}
231
232	*stringlist = NULL;
233	return 0;
234	}
235
236
237
238	/*************************************************
239	* Free store obtained by get_substring_list *
240	*************************************************/
241
242	/* This function exists for the benefit of people calling PCRE from non-C
243	programs that can call its functions, but not free() or (pcre_free)() directly.
244
245	Argument: the result of a previous pcre_get_substring_list()
246	Returns: nothing
247	*/
248
249	void
250	pcre_free_substring_list(const char **pointer)
251	{
252	(pcre_free)((void *)pointer);
253	}
254
255
256
257	/*************************************************
258	* Copy captured string to new store *
259	*************************************************/
260
261	/* This function copies a single captured substring into a piece of new
262	store
263
264	Arguments:
265	subject the subject string that was matched
266	ovector pointer to the offsets table
267	stringcount the number of substrings that were captured
268	(i.e. the yield of the pcre_exec call, unless
269	that was zero, in which case it should be 1/3
270	of the offset table size)
271	stringnumber the number of the required substring
272	stringptr where to put a pointer to the substring
273
274	Returns: if successful:
275	the length of the string, not including the zero that
276	is put on the end; can be zero
277	if not successful:
278	PCRE_ERROR_NOMEMORY (-6) failed to get store
279	PCRE_ERROR_NOSUBSTRING (-7) substring not present
280	*/
281
282	int
283	pcre_get_substring(const char subject, int ovector, int stringcount,
284	int stringnumber, const char **stringptr)
285	{
286	int yield;
287	char *substring;
288	if (stringnumber < 0 \|\| stringnumber >= stringcount)
289	return PCRE_ERROR_NOSUBSTRING;
290	stringnumber *= 2;
291	yield = ovector[stringnumber+1] - ovector[stringnumber];
292	substring = (char *)(pcre_malloc)(yield + 1);
293	if (substring == NULL) return PCRE_ERROR_NOMEMORY;
294	memcpy(substring, subject + ovector[stringnumber], yield);
295	substring[yield] = 0;
296	*stringptr = substring;
297	return yield;
298	}
299
300
301
302	/*************************************************
303	* Copy named captured string to new store *
304	*************************************************/
305
306	/* This function copies a single captured substring, identified by name, into
307	new store.
308
309	Arguments:
310	code the compiled regex
311	subject the subject string that was matched
312	ovector pointer to the offsets table
313	stringcount the number of substrings that were captured
314	(i.e. the yield of the pcre_exec call, unless
315	that was zero, in which case it should be 1/3
316	of the offset table size)
317	stringname the name of the required substring
318	stringptr where to put the pointer
319
320	Returns: if successful:
321	the length of the copied string, not including the zero
322	that is put on the end; can be zero
323	if not successful:
324	PCRE_ERROR_NOMEMORY (-6) couldn't get memory
325	PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
326	*/
327
328	int
329	pcre_get_named_substring(const pcre code, const char subject, int *ovector,
330	int stringcount, const char stringname, const char *stringptr)
331	{
332	int n = pcre_get_stringnumber(code, stringname);
333	if (n <= 0) return n;
334	return pcre_get_substring(subject, ovector, stringcount, n, stringptr);
335	}
336
337
338
339
340	/*************************************************
341	* Free store obtained by get_substring *
342	*************************************************/
343
344	/* This function exists for the benefit of people calling PCRE from non-C
345	programs that can call its functions, but not free() or (pcre_free)() directly.
346
347	Argument: the result of a previous pcre_get_substring()
348	Returns: nothing
349	*/
350
351	void
352	pcre_free_substring(const char *pointer)
353	{
354	(pcre_free)((void *)pointer);
355	}
356
357	/* End of get.c */