X-Git-Url: https://oss.titaniummirror.com/gitweb?p=msp430-binutils.git;a=blobdiff_plain;f=libiberty%2Fmemmem.c;fp=libiberty%2Fmemmem.c;h=5d755992b76ec5f3a5d3087845ec722ea2e65a08;hp=0000000000000000000000000000000000000000;hb=d5da4f291af551c0b8b79e1d4a9b173d60e5c10e;hpb=7b5ea4fcdf2819e070665ab5610f8b48e3867c10 diff --git a/libiberty/memmem.c b/libiberty/memmem.c new file mode 100644 index 0000000..5d75599 --- /dev/null +++ b/libiberty/memmem.c @@ -0,0 +1,70 @@ +/* Copyright (C) 1991,92,93,94,96,97,98,2000,2004,2007 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* + +@deftypefn Supplemental void* memmem (const void *@var{haystack}, size_t @var{haystack_len} const void *@var{needle}, size_t @var{needle_len}) + +Returns a pointer to the first occurrence of @var{needle} (length +@var{needle_len}) in @var{haystack} (length @var{haystack_len}). +Returns @code{NULL} if not found. + +@end deftypefn + +*/ + +#ifndef _LIBC +# include +#endif + +#include +#include + +#ifndef _LIBC +# define __builtin_expect(expr, val) (expr) +#endif + +#undef memmem + +/* Return the first occurrence of NEEDLE in HAYSTACK. */ +void * +memmem (const void *haystack, size_t haystack_len, const void *needle, + size_t needle_len) +{ + const char *begin; + const char *const last_possible + = (const char *) haystack + haystack_len - needle_len; + + if (needle_len == 0) + /* The first occurrence of the empty string is deemed to occur at + the beginning of the string. */ + return (void *) haystack; + + /* Sanity check, otherwise the loop might search through the whole + memory. */ + if (__builtin_expect (haystack_len < needle_len, 0)) + return NULL; + + for (begin = (const char *) haystack; begin <= last_possible; ++begin) + if (begin[0] == ((const char *) needle)[0] && + !memcmp ((const void *) &begin[1], + (const void *) ((const char *) needle + 1), + needle_len - 1)) + return (void *) begin; + + return NULL; +}