jehanne/sys/src/lib/jehanne/port/cistrstr.c

33 lines
819 B
C

/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <libc.h>
char*
jehanne_cistrstr(const char *s, const char *sub)
{
int c, csub, n;
csub = *sub;
if(csub == '\0')
return (char*)s;
if(csub >= 'A' && csub <= 'Z')
csub -= 'A' - 'a';
sub++;
n = jehanne_strlen(sub);
for(; c = *s; s++){
if(c >= 'A' && c <= 'Z')
c -= 'A' - 'a';
if(c == csub && jehanne_cistrncmp(s+1, sub, n) == 0)
return (char*)s;
}
return nil;
}