diff options
author | Sebastian Capella <sebastian.capella@linaro.org> | 2015-07-20 08:57:14 +1000 |
---|---|---|
committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2015-07-22 14:31:51 +1000 |
commit | abeb8ed306151ed5aa6675f986249c1bc73fa80d (patch) | |
tree | 45ecdc8b484037de9d7e4294e7c2abb022d9ec9e | |
parent | 660a997140c3aa0eafd76f234a85ea5641255aef (diff) |
mm/util.c: add kstrimdup()
kstrimdup() creates a whitespace-trimmed duplicate of the passed in
null-terminated string. This is useful for strings coming from sysfs that
often include trailing whitespace due to user input.
Thanks to Joe Perches for this implementation.
Signed-off-by: Sebastian Capella <sebastian.capella@linaro.org>
Cc: Joe Perches <joe@perches.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r-- | include/linux/string.h | 1 | ||||
-rw-r--r-- | mm/util.c | 30 |
2 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/string.h b/include/linux/string.h index a8d90db9c4b0..d5dfe3e75572 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -118,6 +118,7 @@ extern void kfree_const(const void *x); extern char *kstrdup(const char *s, gfp_t gfp); extern const char *kstrdup_const(const char *s, gfp_t gfp); extern char *kstrndup(const char *s, size_t len, gfp_t gfp); +extern char *kstrimdup(const char *s, gfp_t gfp); extern void *kmemdup(const void *src, size_t len, gfp_t gfp); extern char **argv_split(gfp_t gfp, const char *str, int *argcp); diff --git a/mm/util.c b/mm/util.c index 0c7f65e7ef5e..c7434060039b 100644 --- a/mm/util.c +++ b/mm/util.c @@ -3,6 +3,7 @@ #include <linux/string.h> #include <linux/compiler.h> #include <linux/export.h> +#include <linux/ctype.h> #include <linux/err.h> #include <linux/sched.h> #include <linux/security.h> @@ -100,6 +101,35 @@ char *kstrndup(const char *s, size_t max, gfp_t gfp) EXPORT_SYMBOL(kstrndup); /** + * kstrimdup - Trim and copy a %NUL terminated string. + * @s: the string to trim and duplicate + * @gfp: the GFP mask used in the kmalloc() call when allocating memory + * + * Returns an address, which the caller must kfree, containing + * a duplicate of the passed string with leading and/or trailing + * whitespace (as defined by isspace) removed. + */ +char *kstrimdup(const char *s, gfp_t gfp) +{ + char *buf; + char *begin = skip_spaces(s); + size_t len = strlen(begin); + + while (len && isspace(begin[len - 1])) + len--; + + buf = kmalloc_track_caller(len + 1, gfp); + if (!buf) + return NULL; + + memcpy(buf, begin, len); + buf[len] = '\0'; + + return buf; +} +EXPORT_SYMBOL(kstrimdup); + +/** * kmemdup - duplicate region of memory * * @src: memory region to duplicate |