xref: /titanic_50/usr/src/lib/libast/common/comp/regexp.c (revision 36e5aa2ab5c51d4747a2470e41ccb782056c90e7)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *           Copyright (c) 1985-2007 AT&T Knowledge Ventures            *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                      by AT&T Knowledge Ventures                      *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 /*
24  * <regexp.h> library support
25  */
26 
27 #define _REGEXP_DECLARE
28 
29 #include <ast.h>
30 #include <regexp.h>
31 #include <regex.h>
32 #include <align.h>
33 
34 typedef struct
35 {
36 	regex_t		re;
37 	char*		buf;
38 	char*		cur;
39 	unsigned int	size;
40 } Env_t;
41 
42 static void*
43 block(void* handle, void* data, size_t size)
44 {
45 	register Env_t*	env = (Env_t*)handle;
46 
47 	if (data || (size = roundof(size, ALIGN_BOUND2)) > (env->buf + env->size - env->cur))
48 		return 0;
49 	data = (void*)env->cur;
50 	env->cur += size;
51 	return data;
52 }
53 
54 int
55 _re_comp(regexp_t* re, const char* pattern, char* handle, unsigned int size)
56 {
57 	register Env_t*	env = (Env_t*)handle;
58 	register int	n;
59 
60 	if (size <= sizeof(Env_t))
61 		return 50;
62 	env->buf = env->cur = (char*)env + sizeof(Env_t);
63 	env->size = size - sizeof(Env_t);
64 	regalloc(env, block, REG_NOFREE);
65 	n = regcomp(&env->re, pattern, REG_LENIENT|REG_NULL);
66 	switch (n)
67 	{
68 	case 0:
69 		break;
70 	case REG_ERANGE:
71 		n = 11;
72 		break;
73 	case REG_BADBR:
74 		n = 16;
75 		break;
76 	case REG_ESUBREG:
77 		n = 25;
78 		break;
79 	case REG_EPAREN:
80 		n = 42;
81 		break;
82 	case REG_EBRACK:
83 		n = 49;
84 		break;
85 	default:
86 		n = 50;
87 		break;
88 	}
89 	re->re_nbra = env->re.re_nsub;
90 	return n;
91 }
92 
93 int
94 _re_exec(regexp_t* re, const char* subject, const char* handle, int anchor)
95 {
96 	register Env_t*	env = (Env_t*)handle;
97 	register int	n;
98 	regmatch_t	match[elementsof(re->re_braslist)+1];
99 
100 	if (regexec(&env->re, subject, elementsof(match), match, 0) || anchor && match[0].rm_so)
101 		return 0;
102 	re->re_loc1 = (char*)subject + match[0].rm_so;
103 	re->re_loc2 = (char*)subject + match[0].rm_eo;
104 	for (n = 1; n <= env->re.re_nsub; n++)
105 	{
106 		re->re_braslist[n-1] = (char*)subject + match[n].rm_so;
107 		re->re_braelist[n-1] = (char*)subject + match[n].rm_eo;
108 	}
109 	return 1;
110 }
111 
112 char*
113 _re_putc(int c)
114 {
115 	static Sfio_t*	sp;
116 
117 	if (!sp && !(sp = sfstropen()))
118 		return 0;
119 	if (!c)
120 		return sfstruse(sp);
121 	sfputc(sp, c);
122 	return 0;
123 }
124