strtok.c

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/*-
 * Copyright (c) 1998 Softweyr LLC.  All rights reserved.
 *
 * strtok_r, from Berkeley strtok
 * Oct 13, 1998 by Wes Peters <wes@softweyr.com>
 *
 * Copyright (c) 1988, 1993
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notices, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notices, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL SOFTWEYR LLC, THE
 * REGENTS, OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stddef.h>
#ifdef DEBUG_STRTOK
#include <stdio.h>
#endif
#include <string.h>

char* __strtok_r(char* /*s*/ /*s*/, const char* /*delim*/ /*delim*/, char** /*last*/ /*last*/);

char* __strtok_r(char* s, const char* delim, char** last)
{
    char *spanp, *tok;
    int c, sc;

    if(s == NULL && (s = *last) == NULL)
    {
        {
            return (NULL);
        }
    }

/*
 * Skip (span) leading delimiters (s += strspn(s, delim), sort of).
 */
cont:
    c = *s++;
    for(spanp = (char*)(uintptr_t)delim; (sc = *spanp++) != 0;)
    {
        if(c == sc)
        {
            {
                goto cont;
            }
        }
    }

    if(c == 0)
    { /* no non-delimiter characters */
        *last = NULL;
        return (NULL);
    }
    tok = s - 1;

    /*
     * Scan token (scan for delimiters: s += strcspn(s, delim), sort of).
     * Note that delim must have one NUL; we stop if we see that, too.
     */
    for(;;)
    {
        c = *s++;
        spanp = (char*)(uintptr_t)delim;
        do
        {
            if((sc = *spanp++) == c)
            {
                if(c == 0)
                {
                    {
                        s = NULL;
                    }
                }
                else
                {
                    {
                        s[-1] = '\0';
                    }
                }
                *last = s;
                return (tok);
            }
        } while(sc != 0);
    }
    /* NOTREACHED */
}

char* strtok(char* s, const char* delim)
{
    static char* last;

    return (__strtok_r(s, delim, &last));
}

#ifdef DEBUG_STRTOK
/*
 * Test the tokenizer.
 */
int main(void)
{
    char blah[80], test[80];
    char *brkb, *brkt, *phrase, *sep, *word;

    sep = "\\/:;=-";
    phrase = "foo";

    printf("String tokenizer test:\n");
    strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");
    for(word = strtok(test, sep); word; word = strtok(NULL, sep))
        printf("Next word is \"%s\".\n", word);
    strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");

    for(word = strtok_r(test, sep, &brkt); word; word = strtok_r(NULL, sep, &brkt))
    {
        strcpy(blah, "blah:blat:blab:blag");

        for(phrase = strtok_r(blah, sep, &brkb); phrase; phrase = strtok_r(NULL, sep, &brkb))
            printf("So far we're at %s:%s\n", word, phrase);
    }

    return (0);
}

#endif /* DEBUG_STRTOK */