zig/lib/libc/mingw/stdio/strtok_r.c

99 lines
3.1 KiB
C

/*-
* 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.
* 3. 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.
*/
#define _POSIX_SOURCE 1
#include <string.h>
/*
* strtok_r documentation:
* http://pubs.opengroup.org/onlinepubs/009695399/functions/strtok.html
*
* Implementation:
* http://svnweb.freebsd.org/base/head/lib/libc/string/strtok.c?view=co
*
* strtok_r cannot completely be implemented by strtok because of the internal state.
* It breaks when used on 2 strings where they are scanned A, B then A, B.
* Thread-safety is not the issue.
*
* Sample strtok implemenatation, note the internal state:
* char *strtok(char *s, const char *d) { static char *t; return strtok_r(s,d,t); }
*
*/
char *
strtok_r(char * __restrict s, const char * __restrict delim, char ** __restrict 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 *)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 *)delim;
do {
if ((sc = *spanp++) == c) {
if (c == 0)
s = NULL;
else
s[-1] = '\0';
*last = s;
return (tok);
}
} while (sc != 0);
}
/* NOTREACHED */
}