xref: /freebsd/contrib/bmake/stresep.c (revision 3078531de10dcae44b253a35125c949ff4235284)
1 /*	$NetBSD: stresep.c,v 1.4 2017/08/23 10:27:41 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifdef HAVE_CONFIG_H
33 # include <config.h>
34 #endif
35 
36 #include <sys/cdefs.h>
37 
38 #include <assert.h>
39 #include <string.h>
40 
41 #if !defined(HAVE_STRESEP)
42 char * stresep(char **stringp, const char *delim, int esc);
43 /*
44  * Get next token from string *stringp, where tokens are possibly-empty
45  * strings separated by characters from delim. If esc is not NUL, then
46  * the characters followed by esc are ignored and are not taken into account
47  * when splitting the string.
48  *
49  * Writes NULs into the string at *stringp to end tokens.
50  * delim need not remain constant from call to call.
51  * On return, *stringp points past the last NUL written (if there might
52  * be further tokens), or is NULL (if there are definitely no more tokens).
53  *
54  * If *stringp is NULL, stresep returns NULL.
55  */
56 char *
57 stresep(char **stringp, const char *delim, int esc)
58 {
59 	char *s;
60 	const char *spanp;
61 	int c, sc;
62 	size_t l;
63 	char *tok;
64 
65 	if (stringp == NULL || delim == NULL)
66 		return NULL;
67 
68 	if ((s = *stringp) == NULL)
69 		return NULL;
70 	l = strlen(s) + 1;
71 	for (tok = s;;) {
72 		c = *s++;
73 		l--;
74 		while (esc != '\0' && c == esc) {
75 			memmove(s - 1, s, l);
76 			c = *s++;
77 			l--;
78 		}
79 		spanp = delim;
80 		do {
81 			if ((sc = *spanp++) == c) {
82 				if (c == '\0')
83 					s = NULL;
84 				else
85 					s[-1] = '\0';
86 				*stringp = s;
87 				return tok;
88 			}
89 		} while (sc != '\0');
90 	}
91 }
92 #endif
93 
94