xref: /freebsd/lib/libc/regex/regerror.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 1993, 1994 Henry Spencer.
5  * Copyright (c) 1992, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Henry Spencer.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)regerror.c	8.4 (Berkeley) 3/20/94
36  */
37 
38 #if defined(LIBC_SCCS) && !defined(lint)
39 static char sccsid[] = "@(#)regerror.c	8.4 (Berkeley) 3/20/94";
40 #endif /* LIBC_SCCS and not lint */
41 #include <sys/types.h>
42 #include <stdio.h>
43 #include <string.h>
44 #include <limits.h>
45 #include <stdlib.h>
46 #include <regex.h>
47 
48 #include "utils.h"
49 
50 /* ========= begin header generated by ./mkh ========= */
51 #ifdef __cplusplus
52 extern "C" {
53 #endif
54 
55 /* === regerror.c === */
56 static const char *regatoi(const regex_t *preg, char *localbuf);
57 
58 #ifdef __cplusplus
59 }
60 #endif
61 /* ========= end header generated by ./mkh ========= */
62 /*
63  = #define	REG_NOMATCH	 1
64  = #define	REG_BADPAT	 2
65  = #define	REG_ECOLLATE	 3
66  = #define	REG_ECTYPE	 4
67  = #define	REG_EESCAPE	 5
68  = #define	REG_ESUBREG	 6
69  = #define	REG_EBRACK	 7
70  = #define	REG_EPAREN	 8
71  = #define	REG_EBRACE	 9
72  = #define	REG_BADBR	10
73  = #define	REG_ERANGE	11
74  = #define	REG_ESPACE	12
75  = #define	REG_BADRPT	13
76  = #define	REG_EMPTY	14
77  = #define	REG_ASSERT	15
78  = #define	REG_INVARG	16
79  = #define	REG_ILLSEQ	17
80  = #define	REG_ATOI	255	// convert name to number (!)
81  = #define	REG_ITOA	0400	// convert number to name (!)
82  */
83 static struct rerr {
84 	int code;
85 	const char *name;
86 	const char *explain;
87 } rerrs[] = {
88 	{REG_NOMATCH,	"REG_NOMATCH",	"regexec() failed to match"},
89 	{REG_BADPAT,	"REG_BADPAT",	"invalid regular expression"},
90 	{REG_ECOLLATE,	"REG_ECOLLATE",	"invalid collating element"},
91 	{REG_ECTYPE,	"REG_ECTYPE",	"invalid character class"},
92 	{REG_EESCAPE,	"REG_EESCAPE",	"trailing backslash (\\)"},
93 	{REG_ESUBREG,	"REG_ESUBREG",	"invalid backreference number"},
94 	{REG_EBRACK,	"REG_EBRACK",	"brackets ([ ]) not balanced"},
95 	{REG_EPAREN,	"REG_EPAREN",	"parentheses not balanced"},
96 	{REG_EBRACE,	"REG_EBRACE",	"braces not balanced"},
97 	{REG_BADBR,	"REG_BADBR",	"invalid repetition count(s)"},
98 	{REG_ERANGE,	"REG_ERANGE",	"invalid character range"},
99 	{REG_ESPACE,	"REG_ESPACE",	"out of memory"},
100 	{REG_BADRPT,	"REG_BADRPT",	"repetition-operator operand invalid"},
101 	{REG_EMPTY,	"REG_EMPTY",	"empty (sub)expression"},
102 	{REG_ASSERT,	"REG_ASSERT",	"\"can't happen\" -- you found a bug"},
103 	{REG_INVARG,	"REG_INVARG",	"invalid argument to regex routine"},
104 	{REG_ILLSEQ,	"REG_ILLSEQ",	"illegal byte sequence"},
105 	{0,		"",		"*** unknown regexp error code ***"}
106 };
107 
108 /*
109  - regerror - the interface to error numbers
110  = extern size_t regerror(int, const regex_t *, char *, size_t);
111  */
112 /* ARGSUSED */
113 size_t
114 regerror(int errcode,
115 	 const regex_t * __restrict preg,
116 	 char * __restrict errbuf,
117 	 size_t errbuf_size)
118 {
119 	struct rerr *r;
120 	size_t len;
121 	int target = errcode &~ REG_ITOA;
122 	const char *s;
123 	char convbuf[50];
124 
125 	if (errcode == REG_ATOI)
126 		s = regatoi(preg, convbuf);
127 	else {
128 		for (r = rerrs; r->code != 0; r++)
129 			if (r->code == target)
130 				break;
131 
132 		if (errcode&REG_ITOA) {
133 			if (r->code != 0)
134 				(void) strcpy(convbuf, r->name);
135 			else
136 				sprintf(convbuf, "REG_0x%x", target);
137 			assert(strlen(convbuf) < sizeof(convbuf));
138 			s = convbuf;
139 		} else
140 			s = r->explain;
141 	}
142 
143 	len = strlen(s) + 1;
144 	if (errbuf_size > 0) {
145 		if (errbuf_size > len)
146 			(void) strcpy(errbuf, s);
147 		else {
148 			(void) strncpy(errbuf, s, errbuf_size-1);
149 			errbuf[errbuf_size-1] = '\0';
150 		}
151 	}
152 
153 	return(len);
154 }
155 
156 /*
157  - regatoi - internal routine to implement REG_ATOI
158  == static char *regatoi(const regex_t *preg, char *localbuf);
159  */
160 static const char *
161 regatoi(const regex_t *preg, char *localbuf)
162 {
163 	struct rerr *r;
164 
165 	for (r = rerrs; r->code != 0; r++)
166 		if (strcmp(r->name, preg->re_endp) == 0)
167 			break;
168 	if (r->code == 0)
169 		return("0");
170 
171 	sprintf(localbuf, "%d", r->code);
172 	return(localbuf);
173 }
174