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/*
* Adapted from strchr.c code
*
* Copyright (C) 2008 Denys Vlasenko <vda.linux@googlemail.com>
*
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
#include <string.h>
#undef strchrnul
/*#define strchrnul TESTING*/
char *strchrnul(const char *s, int c)
{
int esi;
char *eax;
__asm__ __volatile__(
" movb %%al, %%ah\n"
"1: lodsb\n"
" cmpb %%ah, %%al\n"
" je 2f\n"
" testb %%al, %%al\n"
" jnz 1b\n"
/* with this, we'd get strchr(): */
/* " movl $1, %%esi\n" */
"2: leal -1(%%esi), %%eax\n"
: "=a" (eax), "=&S" (esi)
: "0" (c), "1" (s)
/* no clobbers */
);
return eax;
}
#ifndef strchrnul
libc_hidden_def(strchrnul)
#else
/* Uncomment TESTING, gcc -D_GNU_SOURCE -m32 -Os strchrnul.c -o strchrnul
* and run ./strchrnul
*/
int main()
{
static const char str[] = "abc.def";
printf((char*)strchrnul(str, '.') - str == 3 ? "ok\n" : "BAD!\n");
printf((char*)strchrnul(str, '*') - str == 7 ? "ok\n" : "BAD!\n");
printf((char*)strchrnul(str, 0) - str == 7 ? "ok\n" : "BAD!\n");
printf((char*)strchrnul(str+3, '.') - str == 3 ? "ok\n" : "BAD!\n");
}
#endif
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