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/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <string.h>
#include <stdint.h>
#include <libc-pointer-arith.h>
#undef strcspn
#ifndef STRCSPN
# define STRCSPN strcspn
#endif
/* Return the length of the maximum initial segment of S
which contains no characters from REJECT. */
size_t
STRCSPN (const char *str, const char *reject)
{
if (__glibc_unlikely (reject[0] == '\0')
|| __glibc_unlikely (reject[1] == '\0'))
return __strchrnul (str, reject [0]) - str;
/* Use multiple small memsets to enable inlining on most targets. */
unsigned char table[256];
unsigned char *p = memset (table, 0, 64);
memset (p + 64, 0, 64);
memset (p + 128, 0, 64);
memset (p + 192, 0, 64);
unsigned char *s = (unsigned char*) reject;
unsigned char tmp;
do
p[tmp = *s++] = 1;
while (tmp);
s = (unsigned char*) str;
if (p[s[0]]) return 0;
if (p[s[1]]) return 1;
if (p[s[2]]) return 2;
if (p[s[3]]) return 3;
s = (unsigned char *) PTR_ALIGN_DOWN (s, 4);
unsigned int c0, c1, c2, c3;
do
{
s += 4;
c0 = p[s[0]];
c1 = p[s[1]];
c2 = p[s[2]];
c3 = p[s[3]];
}
while ((c0 | c1 | c2 | c3) == 0);
size_t count = s - (unsigned char *) str;
return (c0 | c1) != 0 ? count - c0 + 1 : count - c2 + 3;
}
libc_hidden_builtin_def (strcspn)
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