diff options
| author | Grant Likely <grant.likely@linaro.org> | 2014-03-14 17:00:14 +0000 |
|---|---|---|
| committer | Grant Likely <grant.likely@linaro.org> | 2014-05-23 11:23:27 +0900 |
| commit | 11d200e95f3e84c1102e4cc9863a3614fd41f3ad (patch) | |
| tree | 2d10860071a5c0d9a39754562ed33e1014faa91e | |
| parent | b44aa25d20e2ef6b824901cbc50a281791f3b421 (diff) | |
lib: add glibc style strchrnul() variant
The strchrnul() variant helpfully returns a the end of the string
instead of a NULL if the requested character is not found. This can
simplify string parsing code since it doesn't need to expicitly check
for a NULL return. If a valid string pointer is passed in, then a valid
null terminated string will always come back out.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
| -rw-r--r-- | include/linux/string.h | 3 | ||||
| -rw-r--r-- | lib/string.c | 18 |
2 files changed, 21 insertions, 0 deletions
diff --git a/include/linux/string.h b/include/linux/string.h index ac889c5ea11b..d36977e029af 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -52,6 +52,9 @@ extern int strncasecmp(const char *s1, const char *s2, size_t n); #ifndef __HAVE_ARCH_STRCHR extern char * strchr(const char *,int); #endif +#ifndef __HAVE_ARCH_STRCHRNUL +extern char * strchrnul(const char *,int); +#endif #ifndef __HAVE_ARCH_STRNCHR extern char * strnchr(const char *, size_t, int); #endif diff --git a/lib/string.c b/lib/string.c index 9b1f9062a202..e0c20eb362f0 100644 --- a/lib/string.c +++ b/lib/string.c @@ -301,6 +301,24 @@ char *strchr(const char *s, int c) EXPORT_SYMBOL(strchr); #endif +#ifndef __HAVE_ARCH_STRCHRNUL +/** + * strchrnul - Find and return a character in a string, or end of string + * @s: The string to be searched + * @c: The character to search for + * + * Returns pointer to first occurrence of 'c' in s. If c is not found, then + * return a pointer to the null byte at the end of s. + */ +char *strchrnul(const char *s, int c) +{ + while (*s && *s != (char)c) + s++; + return (char *)s; +} +EXPORT_SYMBOL(strchrnul); +#endif + #ifndef __HAVE_ARCH_STRRCHR /** * strrchr - Find the last occurrence of a character in a string |