xref: /freebsd/lib/libc/string/wcstok.c (revision 9ad391340ed786640390cea55667544e006f26fd)
1 /*-
2  * Copyright (c) 1998 Softweyr LLC.  All rights reserved.
3  *
4  * strtok_r, from Berkeley strtok
5  * Oct 13, 1998 by Wes Peters <wes@softweyr.com>
6  *
7  * Copyright (c) 1988, 1993
8  *	The Regents of the University of California.  All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notices, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notices, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by Softweyr LLC, the
21  *      University of California, Berkeley, and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
29  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL SOFTWEYR LLC, THE
30  * REGENTS, OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
32  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
34  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
35  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
36  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <wchar.h>
43 
44 wchar_t *
45 wcstok(wchar_t * __restrict s, const wchar_t * __restrict delim,
46     wchar_t ** __restrict last)
47 {
48 	wchar_t *spanp, *tok;
49 	wchar_t c, sc;
50 
51 	if (s == NULL && (s = *last) == NULL)
52 		return (NULL);
53 
54 	/*
55 	 * Skip (span) leading delimiters (s += wcsspn(s, delim), sort of).
56 	 */
57 cont:
58 	c = *s++;
59 	for (spanp = (wchar_t *)delim; (sc = *spanp++) != L'\0';) {
60 		if (c == sc)
61 			goto cont;
62 	}
63 
64 	if (c == L'\0') {	/* no non-delimiter characters */
65 		*last = NULL;
66 		return (NULL);
67 	}
68 	tok = s - 1;
69 
70 	/*
71 	 * Scan token (scan for delimiters: s += wcscspn(s, delim), sort of).
72 	 * Note that delim must have one NUL; we stop if we see that, too.
73 	 */
74 	for (;;) {
75 		c = *s++;
76 		spanp = (wchar_t *)delim;
77 		do {
78 			if ((sc = *spanp++) == c) {
79 				if (c == L'\0')
80 					s = NULL;
81 				else
82 					s[-1] = L'\0';
83 				*last = s;
84 				return (tok);
85 			}
86 		} while (sc != L'\0');
87 	}
88 	/* NOTREACHED */
89 }
90