xref: /dragonfly/lib/libc/string/strtok.c (revision 19fe1c42)
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  *
14  * 1. Redistributions of source code must retain the above copyright
15  *    notices, this list of conditions and the following disclaimer.
16  *
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notices, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *
24  *	This product includes software developed by Softweyr LLC, the
25  *      University of California, Berkeley, and its contributors.
26  *
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND CONTRIBUTORS
32  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
34  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL SOFTWEYR LLC, THE
35  * REGENTS, OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
37  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
38  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
39  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
40  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
41  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42  *
43  * $FreeBSD: src/lib/libc/string/strtok.c,v 1.2.6.1 2001/07/09 23:30:07 obrien Exp $
44  * $DragonFly: src/lib/libc/string/strtok.c,v 1.3 2005/04/28 13:25:12 joerg Exp $
45  */
46 
47 #include <stddef.h>
48 #include <string.h>
49 
50 char *
51 strtok_r(char *s, const char *delim, char **last)
52 {
53     const char *spanp;
54     int c, sc;
55     char *tok;
56 
57     if (s == NULL && (s = *last) == NULL)
58     {
59 	return NULL;
60     }
61 
62     /*
63      * Skip (span) leading delimiters (s += strspn(s, delim), sort of).
64      */
65 cont:
66     c = *s++;
67     for (spanp = delim; (sc = *spanp++) != 0; )
68     {
69 	if (c == sc)
70 	{
71 	    goto cont;
72 	}
73     }
74 
75     if (c == 0)		/* no non-delimiter characters */
76     {
77 	*last = NULL;
78 	return NULL;
79     }
80     tok = s - 1;
81 
82     /*
83      * Scan token (scan for delimiters: s += strcspn(s, delim), sort of).
84      * Note that delim must have one NUL; we stop if we see that, too.
85      */
86     for (;;)
87     {
88 	c = *s++;
89 	spanp = delim;
90 	do
91 	{
92 	    if ((sc = *spanp++) == c)
93 	    {
94 		if (c == 0)
95 		{
96 		    s = NULL;
97 		}
98 		else
99 		{
100 		    char *w = s - 1;
101 		    *w = '\0';
102 		}
103 		*last = s;
104 		return tok;
105 	    }
106 	}
107 	while (sc != 0);
108     }
109     /* NOTREACHED */
110 }
111 
112 
113 char *
114 strtok(char *s, const char *delim)
115 {
116     static char *last;
117 
118     return strtok_r(s, delim, &last);
119 }
120 
121 
122 #if defined(DEBUG_STRTOK)
123 
124 /*
125  * Test the tokenizer.
126  */
127 int
128 main()
129 {
130     char test[80], blah[80];
131     char *sep = "\\/:;=-";
132     char *word, *phrase, *brkt, *brkb;
133 
134     printf("String tokenizer test:\n");
135 
136     strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");
137 
138     for (word = strtok(test, sep);
139 	 word;
140 	 word = strtok(NULL, sep))
141     {
142 	printf("Next word is \"%s\".\n", word);
143     }
144 
145     phrase = "foo";
146 
147     strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");
148 
149     for (word = strtok_r(test, sep, &brkt);
150 	 word;
151 	 word = strtok_r(NULL, sep, &brkt))
152     {
153 	strcpy(blah, "blah:blat:blab:blag");
154 
155 	for (phrase = strtok_r(blah, sep, &brkb);
156 	     phrase;
157 	     phrase = strtok_r(NULL, sep, &brkb))
158 	{
159 	    printf("So far we're at %s:%s\n", word, phrase);
160 	}
161     }
162 
163     return 0;
164 }
165 
166 #endif /* DEBUG_STRTOK */
167