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Diffstat (limited to 'REORG.TODO/string/strcspn.c')
-rw-r--r-- | REORG.TODO/string/strcspn.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/REORG.TODO/string/strcspn.c b/REORG.TODO/string/strcspn.c new file mode 100644 index 0000000000..1035552a8e --- /dev/null +++ b/REORG.TODO/string/strcspn.c @@ -0,0 +1,72 @@ +/* Copyright (C) 1991-2017 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 + <http://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) |