xref: /freebsd/lib/libc/regex/regerror.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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 
36 #include <sys/types.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <limits.h>
40 #include <stdlib.h>
41 #include <regex.h>
42 
43 #include "utils.h"
44 
45 /* ========= begin header generated by ./mkh ========= */
46 #ifdef __cplusplus
47 extern "C" {
48 #endif
49 
50 /* === regerror.c === */
51 static const char *regatoi(const regex_t *preg, char *localbuf);
52 
53 #ifdef __cplusplus
54 }
55 #endif
56 /* ========= end header generated by ./mkh ========= */
57 /*
58  = #define	REG_NOMATCH	 1
59  = #define	REG_BADPAT	 2
60  = #define	REG_ECOLLATE	 3
61  = #define	REG_ECTYPE	 4
62  = #define	REG_EESCAPE	 5
63  = #define	REG_ESUBREG	 6
64  = #define	REG_EBRACK	 7
65  = #define	REG_EPAREN	 8
66  = #define	REG_EBRACE	 9
67  = #define	REG_BADBR	10
68  = #define	REG_ERANGE	11
69  = #define	REG_ESPACE	12
70  = #define	REG_BADRPT	13
71  = #define	REG_EMPTY	14
72  = #define	REG_ASSERT	15
73  = #define	REG_INVARG	16
74  = #define	REG_ILLSEQ	17
75  = #define	REG_ATOI	255	// convert name to number (!)
76  = #define	REG_ITOA	0400	// convert number to name (!)
77  */
78 static struct rerr {
79 	int code;
80 	const char *name;
81 	const char *explain;
82 } rerrs[] = {
83 	{REG_NOMATCH,	"REG_NOMATCH",	"regexec() failed to match"},
84 	{REG_BADPAT,	"REG_BADPAT",	"invalid regular expression"},
85 	{REG_ECOLLATE,	"REG_ECOLLATE",	"invalid collating element"},
86 	{REG_ECTYPE,	"REG_ECTYPE",	"invalid character class"},
87 	{REG_EESCAPE,	"REG_EESCAPE",	"trailing backslash (\\)"},
88 	{REG_ESUBREG,	"REG_ESUBREG",	"invalid backreference number"},
89 	{REG_EBRACK,	"REG_EBRACK",	"brackets ([ ]) not balanced"},
90 	{REG_EPAREN,	"REG_EPAREN",	"parentheses not balanced"},
91 	{REG_EBRACE,	"REG_EBRACE",	"braces not balanced"},
92 	{REG_BADBR,	"REG_BADBR",	"invalid repetition count(s)"},
93 	{REG_ERANGE,	"REG_ERANGE",	"invalid character range"},
94 	{REG_ESPACE,	"REG_ESPACE",	"out of memory"},
95 	{REG_BADRPT,	"REG_BADRPT",	"repetition-operator operand invalid"},
96 	{REG_EMPTY,	"REG_EMPTY",	"empty (sub)expression"},
97 	{REG_ASSERT,	"REG_ASSERT",	"\"can't happen\" -- you found a bug"},
98 	{REG_INVARG,	"REG_INVARG",	"invalid argument to regex routine"},
99 	{REG_ILLSEQ,	"REG_ILLSEQ",	"illegal byte sequence"},
100 	{0,		"",		"*** unknown regexp error code ***"}
101 };
102 
103 /*
104  - regerror - the interface to error numbers
105  = extern size_t regerror(int, const regex_t *, char *, size_t);
106  */
107 /* ARGSUSED */
108 size_t
109 regerror(int errcode,
110 	 const regex_t * __restrict preg,
111 	 char * __restrict errbuf,
112 	 size_t errbuf_size)
113 {
114 	struct rerr *r;
115 	size_t len;
116 	int target = errcode &~ REG_ITOA;
117 	const char *s;
118 	char convbuf[50];
119 
120 	if (errcode == REG_ATOI)
121 		s = regatoi(preg, convbuf);
122 	else {
123 		for (r = rerrs; r->code != 0; r++)
124 			if (r->code == target)
125 				break;
126 
127 		if (errcode&REG_ITOA) {
128 			if (r->code != 0)
129 				(void) strcpy(convbuf, r->name);
130 			else
131 				sprintf(convbuf, "REG_0x%x", target);
132 			assert(strlen(convbuf) < sizeof(convbuf));
133 			s = convbuf;
134 		} else
135 			s = r->explain;
136 	}
137 
138 	len = strlen(s) + 1;
139 	if (errbuf_size > 0) {
140 		if (errbuf_size > len)
141 			(void) strcpy(errbuf, s);
142 		else {
143 			(void) strncpy(errbuf, s, errbuf_size-1);
144 			errbuf[errbuf_size-1] = '\0';
145 		}
146 	}
147 
148 	return(len);
149 }
150 
151 /*
152  - regatoi - internal routine to implement REG_ATOI
153  == static char *regatoi(const regex_t *preg, char *localbuf);
154  */
155 static const char *
156 regatoi(const regex_t *preg, char *localbuf)
157 {
158 	struct rerr *r;
159 
160 	for (r = rerrs; r->code != 0; r++)
161 		if (strcmp(r->name, preg->re_endp) == 0)
162 			break;
163 	if (r->code == 0)
164 		return("0");
165 
166 	sprintf(localbuf, "%d", r->code);
167 	return(localbuf);
168 }
169