From c626d61db05ff31afd55834d69fa9b7df5365dad Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Tue, 1 Sep 2015 02:57:30 +0200 Subject: add strchr and variants MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- include/string.h | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 102 insertions(+), 2 deletions(-) (limited to 'include/string.h') diff --git a/include/string.h b/include/string.h index 604fe1a..f1cc0c1 100644 --- a/include/string.h +++ b/include/string.h @@ -744,8 +744,108 @@ int strncmp(const char*, const char*, size_t) #if defined(_GNU_SOURCE) && !defined(__PORTABLE) int strverscmp(const char*, const char*) - __GCC_ONLY(__attribute__((warn_unused_result, nonnull))); /* TODO document and implement strverscmp */ -#end if + __GCC_ONLY(__attribute__((warn_unused_result, nonnull))); +/* TODO document and implement strverscmp */ +#endif + + +/** + * Find the first occurrence of a byte in a memory segment. + * + * @param segment The memory segment to search. + * @param c The sought after character. + * @param size The size of the memory segment. + * @return Pointer to the first occurrence of `c`, + * `NULL` if none were found. + */ +void* memchr(const void*, int, size_t) + __GCC_ONLY(__attribute__((warn_unused_result))); + +#if (defined(_GNU_SOURCE) || defined(_SLIBC_SOURCE)) && !defined(__PORTABLE) +/** + * Find the first occurrence of a byte in a memory segment. + * The memory segment must be known to contain the sought after byte. + * + * This is a GNU-compliant slibc extension. + * + * @param segment The memory segment to search. + * @param c The sought after character. + * @return Pointer to the first occurrence of `c`. + */ +void* rawmemchr(const void*, int) + __GCC_ONLY(__attribute__((warn_unused_result, returns_nonnull, nonnull))); +#endif + +/** + * Find the last occurrence of a byte in a memory segment. + * + * For improved performace, use this function instead + * of `strrchr` if you already know the length of the + * string. + * + * @param segment The memory segment to search. + * @param c The sought after character. + * @param size The size of the memory segment. + * @return Pointer to the last occurrence of `c`, + * `NULL` if none were found. + */ +void* memrchr(const void*, int, size_t) + __GCC_ONLY(__attribute__((warn_unused_result))); + +/** + * Find the first occurrence of a byte in a string. + * + * `s = strchr(s, 0)` is a faster alternative to + * `s = s + strlen(s)`. + * + * @param string The string to search. + * The terminating NUL character is + * considered a part of the string. + * @param c The sought after character. + * @return Pointer to the first occurrence of `c`, + * `NULL` if none were found. + */ +char* strchr(const char*, int) + __GCC_ONLY(__attribute__((warn_unused_result, nonnull))); + +#if (defined(_GNU_SOURCE) || defined(_SLIBC_SOURCE)) && !defined(__PORTABLE) +/** + * Find the first occurrence of a byte in a string, or + * if there is no such byte, the end of the string. + * + * This is a GNU-compliant slibc extension. + * + * @param string The string to search. + * The terminating NUL character is + * considered a part of the string. + * @param c The sought after character. + * @return Pointer to the first occurrence of `c`, + * Pointer to the terminating NUL character + * if none were found. + */ +char* strchrnul(const char*, int) + __GCC_ONLY(__attribute__((warn_unused_result, returns_nonnull, nonnull))); +#endif + +/** + * Find the last occurrence of a byte in a string. + * + * For improved performace, use `memrchr` instead of + * this function if you already know the length of the + * string. + * + * @param string The string to search. + * The terminating NUL character is + * considered a part of the string. + * @param c The sought after character. + * @return Pointer to the last occurrence of `c`, + * `NULL` if none were found. + */ +char* strrchr(const char*, int) + __GCC_ONLY(__attribute__((warn_unused_result, nonnull))); + + +/* TODO Add case insensitive character searching functions. */ -- cgit v1.2.3-70-g09d2