diff options
Diffstat (limited to 'libc/string/memchr.c')
-rw-r--r-- | libc/string/memchr.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/libc/string/memchr.c b/libc/string/memchr.c new file mode 100644 index 0000000..b14167a --- /dev/null +++ b/libc/string/memchr.c @@ -0,0 +1,46 @@ +/* + * Copyright (C) 2008 The Android Open Source Project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * 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. + * + * 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 OWNER 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. + */ +#include <stddef.h> +#include <string.h> + +void *memchr(const void *s, int c, size_t n) +{ + const unsigned char* p = s; + const unsigned char* end = p + n; + + for (;;) { + if (p >= end || p[0] == c) break; p++; + if (p >= end || p[0] == c) break; p++; + if (p >= end || p[0] == c) break; p++; + if (p >= end || p[0] == c) break; p++; + } + if (p >= end) + return NULL; + else + return (void*) p; +} |