xref: /titanic_50/usr/src/lib/libast/common/comp/regexp.c (revision 112cd14a18db3bd3fac4ff92c4117b51ddd339ab)
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