1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17/* Derived from PCRE's pcreposix.h.
18
19            Copyright (c) 1997-2004 University of Cambridge
20
21-----------------------------------------------------------------------------
22Redistribution and use in source and binary forms, with or without
23modification, are permitted provided that the following conditions are met:
24
25    * Redistributions of source code must retain the above copyright notice,
26      this list of conditions and the following disclaimer.
27
28    * Redistributions in binary form must reproduce the above copyright
29      notice, this list of conditions and the following disclaimer in the
30      documentation and/or other materials provided with the distribution.
31
32    * Neither the name of the University of Cambridge nor the names of its
33      contributors may be used to endorse or promote products derived from
34      this software without specific prior written permission.
35
36THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
37AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
40LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
41CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
42SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
43INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
44CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
46POSSIBILITY OF SUCH DAMAGE.
47-----------------------------------------------------------------------------
48*/
49
50/**
51 * @file ap_regex.h
52 * @brief Apache Regex defines
53 */
54
55#ifndef AP_REGEX_H
56#define AP_REGEX_H
57
58#include "apr.h"
59
60/* Allow for C++ users */
61
62#ifdef __cplusplus
63extern "C" {
64#endif
65
66/* Options for ap_regcomp, ap_regexec, and ap_rxplus versions: */
67
68#define AP_REG_ICASE    0x01 /** use a case-insensitive match */
69#define AP_REG_NEWLINE  0x02 /** don't match newlines against '.' etc */
70#define AP_REG_NOTBOL   0x04 /** ^ will not match against start-of-string */
71#define AP_REG_NOTEOL   0x08 /** $ will not match against end-of-string */
72
73#define AP_REG_EXTENDED (0)  /** unused */
74#define AP_REG_NOSUB    (0)  /** unused */
75
76#define AP_REG_MULTI 0x10    /* perl's /g (needs fixing) */
77#define AP_REG_NOMEM 0x20    /* nomem in our code */
78#define AP_REG_DOTALL 0x40   /* perl's /s flag */
79
80#define AP_REG_MATCH "MATCH_" /** suggested prefix for ap_regname */
81
82/* Error values: */
83enum {
84  AP_REG_ASSERT = 1,  /** internal error ? */
85  AP_REG_ESPACE,      /** failed to get memory */
86  AP_REG_INVARG,      /** invalid argument */
87  AP_REG_NOMATCH      /** match failed */
88};
89
90/* The structure representing a compiled regular expression. */
91typedef struct {
92    void *re_pcre;
93    int re_nsub;
94    apr_size_t re_erroffset;
95} ap_regex_t;
96
97/* The structure in which a captured offset is returned. */
98typedef struct {
99    int rm_so;
100    int rm_eo;
101} ap_regmatch_t;
102
103/* The functions */
104
105/**
106 * Compile a regular expression.
107 * @param preg Returned compiled regex
108 * @param regex The regular expression string
109 * @param cflags Bitwise OR of AP_REG_* flags (ICASE and NEWLINE supported,
110 *                                             other flags are ignored)
111 * @return Zero on success or non-zero on error
112 */
113AP_DECLARE(int) ap_regcomp(ap_regex_t *preg, const char *regex, int cflags);
114
115/**
116 * Match a NUL-terminated string against a pre-compiled regex.
117 * @param preg The pre-compiled regex
118 * @param string The string to match
119 * @param nmatch Provide information regarding the location of any matches
120 * @param pmatch Provide information regarding the location of any matches
121 * @param eflags Bitwise OR of AP_REG_* flags (NOTBOL and NOTEOL supported,
122 *                                             other flags are ignored)
123 * @return 0 for successful match, \p AP_REG_NOMATCH otherwise
124 */
125AP_DECLARE(int) ap_regexec(const ap_regex_t *preg, const char *string,
126                           apr_size_t nmatch, ap_regmatch_t *pmatch, int eflags);
127
128/**
129 * Match a string with given length against a pre-compiled regex. The string
130 * does not need to be NUL-terminated.
131 * @param preg The pre-compiled regex
132 * @param buff The string to match
133 * @param len Length of the string to match
134 * @param nmatch Provide information regarding the location of any matches
135 * @param pmatch Provide information regarding the location of any matches
136 * @param eflags Bitwise OR of AP_REG_* flags (NOTBOL and NOTEOL supported,
137 *                                             other flags are ignored)
138 * @return 0 for successful match, AP_REG_NOMATCH otherwise
139 */
140AP_DECLARE(int) ap_regexec_len(const ap_regex_t *preg, const char *buff,
141                               apr_size_t len, apr_size_t nmatch,
142                               ap_regmatch_t *pmatch, int eflags);
143
144/**
145 * Return the error code returned by regcomp or regexec into error messages
146 * @param errcode the error code returned by regexec or regcomp
147 * @param preg The precompiled regex
148 * @param errbuf A buffer to store the error in
149 * @param errbuf_size The size of the buffer
150 */
151AP_DECLARE(apr_size_t) ap_regerror(int errcode, const ap_regex_t *preg,
152                                   char *errbuf, apr_size_t errbuf_size);
153
154/**
155 * Return an array of named regex backreferences
156 * @param preg The precompiled regex
157 * @param names The array to which the names will be added
158 * @param upper If non zero, uppercase the names
159 */
160AP_DECLARE(int) ap_regname(const ap_regex_t *preg,
161                           apr_array_header_t *names, const char *prefix,
162                           int upper);
163
164/** Destroy a pre-compiled regex.
165 * @param preg The pre-compiled regex to free.
166 */
167AP_DECLARE(void) ap_regfree(ap_regex_t *preg);
168
169/* ap_rxplus: higher-level regexps */
170
171typedef struct {
172    ap_regex_t rx;
173    apr_uint32_t flags;
174    const char *subs;
175    const char *match;
176    apr_size_t nmatch;
177    ap_regmatch_t *pmatch;
178} ap_rxplus_t;
179
180/**
181 * Compile a pattern into a regexp.
182 * supports perl-like formats
183 *    match-string
184 *    /match-string/flags
185 *    s/match-string/replacement-string/flags
186 *    Intended to support more perl-like stuff as and when round tuits happen
187 * match-string is anything supported by ap_regcomp
188 * replacement-string is a substitution string as supported in ap_pregsub
189 * flags should correspond with perl syntax: treat failure to do so as a bug
190 *                                           (documentation TBD)
191 * @param pool Pool to allocate from
192 * @param pattern Pattern to compile
193 * @return Compiled regexp, or NULL in case of compile/syntax error
194 */
195AP_DECLARE(ap_rxplus_t*) ap_rxplus_compile(apr_pool_t *pool, const char *pattern);
196/**
197 * Apply a regexp operation to a string.
198 * @param pool Pool to allocate from
199 * @param rx The regex match to apply
200 * @param pattern The string to apply it to
201 *                NOTE: This MUST be kept in scope to use regexp memory
202 * @param newpattern The modified string (ignored if the operation doesn't
203 *                                        modify the string)
204 * @return Number of times a match happens.  Normally 0 (no match) or 1
205 *         (match found), but may be greater if a transforming pattern
206 *         is applied with the 'g' flag.
207 */
208AP_DECLARE(int) ap_rxplus_exec(apr_pool_t *pool, ap_rxplus_t *rx,
209                               const char *pattern, char **newpattern);
210#ifdef DOXYGEN
211/**
212 * Number of matches in the regexp operation's memory
213 * This may be 0 if no match is in memory, or up to nmatch from compilation
214 * @param rx The regexp
215 * @return Number of matches in memory
216 */
217AP_DECLARE(int) ap_rxplus_nmatch(ap_rxplus_t *rx);
218#else
219#define ap_rxplus_nmatch(rx) (((rx)->match != NULL) ? (rx)->nmatch : 0)
220#endif
221/**
222 * Get a pointer to a match from regex memory
223 * NOTE: this relies on the match pattern from the last call to
224 *       ap_rxplus_exec still being valid (i.e. not freed or out-of-scope)
225 * @param rx The regexp
226 * @param n The match number to retrieve (must be between 0 and nmatch)
227 * @param len Returns the length of the match.
228 * @param match Returns the match pattern
229 */
230AP_DECLARE(void) ap_rxplus_match(ap_rxplus_t *rx, int n, int *len,
231                                 const char **match);
232/**
233 * Get a match from regex memory in a string copy
234 * NOTE: this relies on the match pattern from the last call to
235 *       ap_rxplus_exec still being valid (i.e. not freed or out-of-scope)
236 * @param pool Pool to allocate from
237 * @param rx The regexp
238 * @param n The match number to retrieve (must be between 0 and nmatch)
239 * @return The matched string
240 */
241AP_DECLARE(char*) ap_rxplus_pmatch(apr_pool_t *pool, ap_rxplus_t *rx, int n);
242
243#ifdef __cplusplus
244}   /* extern "C" */
245#endif
246
247#endif /* AP_REGEX_T */
248
249