1 /* Copyright (C) 1996, 1997, 1998, 1999, 2004, 2008, 2012
2 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <[email protected]>, 1996.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef _REGEXP_H
21 #define _REGEXP_H 1
22
23 /* The contents of this header file was first standardized in X/Open
24 System Interface and Headers Issue 2, originally coming from SysV.
25 In issue 4, version 2, it is marked as TO BE WITDRAWN, and it has
26 been withdrawn in SUSv3.
27
28 This code shouldn't be used in any newly written code. It is
29 included only for compatibility reasons. Use the POSIX definition
30 in <regex.h> for portable applications and a reasonable interface. */
31
32 #include <features.h>
33 #include <alloca.h>
34 #include <regex.h>
35 #include <stdlib.h>
36 #include <string.h>
37
38 /* The implementation provided here emulates the needed functionality
39 by mapping to the POSIX regular expression matcher. The interface
40 for the here included function is weird (this really is a harmless
41 word).
42
43 The user has to provide six macros before this header file can be
44 included:
45
46 INIT Declarations vor variables which can be used by the
47 other macros.
48
49 GETC() Return the value of the next character in the regular
50 expression pattern. Successive calls should return
51 successive characters.
52
53 PEEKC() Return the value of the next character in the regular
54 expression pattern. Immediately successive calls to
55 PEEKC() should return the same character which should
56 also be the next character returned by GETC().
57
58 UNGETC(c) Cause `c' to be returned by the next call to GETC() and
59 PEEKC().
60
61 RETURN(ptr) Used for normal exit of the `compile' function. `ptr'
62 is a pointer to the character after the last character of
63 the compiled regular expression.
64
65 ERROR(val) Used for abnormal return from `compile'. `val' is the
66 error number. The error codes are:
67 11 Range endpoint too large.
68 16 Bad number.
69 25 \digit out of range.
70 36 Illegal or missing delimiter.
71 41 No remembered search string.
72 42 \( \) imbalance.
73 43 Too many \(.
74 44 More tan two numbers given in \{ \}.
75 45 } expected after \.
76 46 First number exceeds second in \{ \}.
77 49 [ ] imbalance.
78 50 Regular expression overflow.
79
80 */
81
82 __BEGIN_DECLS
83
84 /* Interface variables. They contain the results of the successful
85 calls to `setp' and `advance'. */
86 extern char *loc1;
87 extern char *loc2;
88
89 /* The use of this variable in the `advance' function is not
90 supported. */
91 extern char *locs;
92
93
94 #ifndef __DO_NOT_DEFINE_COMPILE
95 /* Get and compile the user supplied pattern up to end of line or
96 string or until EOF is seen, whatever happens first. The result is
97 placed in the buffer starting at EXPBUF and delimited by ENDBUF.
98
99 This function cannot be defined in the libc itself since it depends
100 on the macros. */
101 char *
compile(char * __restrict instring,char * __restrict expbuf,const char * __restrict endbuf,int eof)102 compile (char *__restrict instring, char *__restrict expbuf,
103 const char *__restrict endbuf, int eof)
104 {
105 char *__input_buffer = NULL;
106 size_t __input_size = 0;
107 size_t __current_size = 0;
108 int __ch;
109 int __error;
110 INIT
111
112 /* Align the expression buffer according to the needs for an object
113 of type `regex_t'. Then check for minimum size of the buffer for
114 the compiled regular expression. */
115 regex_t *__expr_ptr;
116 # if defined __GNUC__ && __GNUC__ >= 2
117 const size_t __req = __alignof__ (regex_t *);
118 # else
119 /* How shall we find out? We simply guess it and can change it is
120 this really proofs to be wrong. */
121 const size_t __req = 8;
122 # endif
123 expbuf += __req;
124 expbuf -= (expbuf - ((char *) 0)) % __req;
125 if (endbuf < expbuf + sizeof (regex_t))
126 {
127 ERROR (50);
128 }
129 __expr_ptr = (regex_t *) expbuf;
130 /* The remaining space in the buffer can be used for the compiled
131 pattern. */
132 __expr_ptr->__REPB_PREFIX (buffer) = expbuf + sizeof (regex_t);
133 __expr_ptr->__REPB_PREFIX (allocated)
134 = endbuf - (char *) __expr_ptr->__REPB_PREFIX (buffer);
135
136 while ((__ch = (GETC ())) != eof)
137 {
138 if (__ch == '\0' || __ch == '\n')
139 {
140 UNGETC (__ch);
141 break;
142 }
143
144 if (__current_size + 1 >= __input_size)
145 {
146 size_t __new_size = __input_size ? 2 * __input_size : 128;
147 char *__new_room = (char *) alloca (__new_size);
148 /* See whether we can use the old buffer. */
149 if (__new_room + __new_size == __input_buffer)
150 {
151 __input_size += __new_size;
152 __input_buffer = (char *) memcpy (__new_room, __input_buffer,
153 __current_size);
154 }
155 else if (__input_buffer + __input_size == __new_room)
156 __input_size += __new_size;
157 else
158 {
159 __input_size = __new_size;
160 __input_buffer = (char *) memcpy (__new_room, __input_buffer,
161 __current_size);
162 }
163 }
164 __input_buffer[__current_size++] = __ch;
165 }
166 if (__current_size)
167 __input_buffer[__current_size++] = '\0';
168 else
169 __input_buffer = "";
170
171 /* Now compile the pattern. */
172 __error = regcomp (__expr_ptr, __input_buffer, REG_NEWLINE);
173 if (__error != 0)
174 /* Oh well, we have to translate POSIX error codes. */
175 switch (__error)
176 {
177 case REG_BADPAT:
178 case REG_ECOLLATE:
179 case REG_ECTYPE:
180 case REG_EESCAPE:
181 case REG_BADRPT:
182 case REG_EEND:
183 case REG_ERPAREN:
184 default:
185 /* There is no matching error code. */
186 RETURN (36);
187 case REG_ESUBREG:
188 RETURN (25);
189 case REG_EBRACK:
190 RETURN (49);
191 case REG_EPAREN:
192 RETURN (42);
193 case REG_EBRACE:
194 RETURN (44);
195 case REG_BADBR:
196 RETURN (46);
197 case REG_ERANGE:
198 RETURN (11);
199 case REG_ESPACE:
200 case REG_ESIZE:
201 ERROR (50);
202 }
203
204 /* Everything is ok. */
205 RETURN ((char *) (__expr_ptr->__REPB_PREFIX (buffer)
206 + __expr_ptr->__REPB_PREFIX (used)));
207 }
208 #endif
209
210
211 /* Find the next match in STRING. The compiled regular expression is
212 found in the buffer starting at EXPBUF. `loc1' will return the
213 first character matched and `loc2' points to the next unmatched
214 character. */
215 extern int step (const char *__restrict __string,
216 const char *__restrict __expbuf) __THROW;
217
218 /* Match the beginning of STRING with the compiled regular expression
219 in EXPBUF. If the match is successful `loc2' will contain the
220 position of the first unmatched character. */
221 extern int advance (const char *__restrict __string,
222 const char *__restrict __expbuf) __THROW;
223
224
225 __END_DECLS
226
227 #endif /* regexp.h */
228