diff options
Diffstat (limited to 'lib/libutils/isoc/newlib/strcmp.c')
| -rw-r--r-- | lib/libutils/isoc/newlib/strcmp.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/lib/libutils/isoc/newlib/strcmp.c b/lib/libutils/isoc/newlib/strcmp.c new file mode 100644 index 0000000..0867f54 --- /dev/null +++ b/lib/libutils/isoc/newlib/strcmp.c @@ -0,0 +1,140 @@ +/* + * Copyright (c) 1994-2009 Red Hat, Inc. + * 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 notice, + * this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * 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 copyright holder 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 THE COPYRIGHT HOLDERS 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 THE COPYRIGHT HOLDER 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. + */ + +/* This file is copied from newlib-1.19 */ + +/* +FUNCTION + <<strcmp>>---character string compare + +INDEX + strcmp + +ANSI_SYNOPSIS + #include <string.h> + int strcmp(const char *<[a]>, const char *<[b]>); + +TRAD_SYNOPSIS + #include <string.h> + int strcmp(<[a]>, <[b]>) + char *<[a]>; + char *<[b]>; + +DESCRIPTION + <<strcmp>> compares the string at <[a]> to + the string at <[b]>. + +RETURNS + If <<*<[a]>>> sorts lexicographically after <<*<[b]>>>, + <<strcmp>> returns a number greater than zero. If the two + strings match, <<strcmp>> returns zero. If <<*<[a]>>> + sorts lexicographically before <<*<[b]>>>, <<strcmp>> returns a + number less than zero. + +PORTABILITY +<<strcmp>> is ANSI C. + +<<strcmp>> requires no supporting OS subroutines. + +QUICKREF + strcmp ansi pure +*/ + +#include "_ansi.h" +#include <string.h> +#include <limits.h> + +/* Nonzero if either X or Y is not aligned on a "long" boundary. */ +#define UNALIGNED(X, Y) \ + (((long)X & (sizeof(long) - 1)) | ((long)Y & (sizeof(long) - 1))) + +/* DETECTNULL returns nonzero if (long)X contains a NULL byte. */ +#if LONG_MAX == 2147483647L +#define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080) +#else +#if LONG_MAX == 9223372036854775807L +#define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080) +#else +#error long int is not a 32bit or 64bit type. +#endif +#endif + +#ifndef DETECTNULL +#error long int is not a 32bit or 64bit byte +#endif + +int _DEFUN(strcmp, (s1, s2), _CONST char *s1 _AND _CONST char *s2) +{ +#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__) + while (*s1 != '\0' && *s1 == *s2) { + s1++; + s2++; + } + + return (*(unsigned char *)s1) - (*(unsigned char *)s2); +#else + unsigned long *a1; + unsigned long *a2; + + /* If s1 or s2 are unaligned, then compare bytes. */ + if (!UNALIGNED(s1, s2)) { + /* + * If s1 and s2 are word-aligned, compare them a word at a time. + */ + a1 = (unsigned long *)s1; + a2 = (unsigned long *)s2; + while (*a1 == *a2) { + /* + * To get here, *a1 == *a2, thus if we find a null in + * *a1, then the strings must be equal, so return zero. + */ + if (DETECTNULL(*a1)) + return 0; + + a1++; + a2++; + } + + /* + * A difference was detected in last few bytes of s1, so search + * bytewise. + */ + s1 = (char *)a1; + s2 = (char *)a2; + } + + while (*s1 != '\0' && *s1 == *s2) { + s1++; + s2++; + } + return (*(unsigned char *)s1) - (*(unsigned char *)s2); +#endif /* not PREFER_SIZE_OVER_SPEED */ +} |