From bec90733b9de6e7d75b8bda19b3f0a7117e6b78d Mon Sep 17 00:00:00 2001 From: Manuel Novoa III Date: Thu, 2 Sep 2004 14:39:38 +0000 Subject: Add a couple of mips-specific string funcs. Port the generic optimized string funcs from glibc, with some tweaks to cut their size a little. The main change is making memmove call memcpy for forward copying to trim redundant code. Make use of both the generic and arch-specific speed-optimized string funcs configurable. Arch-specific take precedence over generic, and generic takes precedence over basic size-optimized uClibc funcs. --- libc/string/generic/memmem.c | 50 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 libc/string/generic/memmem.c (limited to 'libc/string/generic/memmem.c') diff --git a/libc/string/generic/memmem.c b/libc/string/generic/memmem.c new file mode 100644 index 000000000..c0f2bd192 --- /dev/null +++ b/libc/string/generic/memmem.c @@ -0,0 +1,50 @@ +/* Copyright (C) 1991,92,93,94,96,97,98,2000 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include + +#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; +} -- cgit v1.2.3