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.cape...@linaro.org>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Joe Perches <j...@perches.com>
Cc: Mikulas Patocka <mpato...@redhat.com>
Cc: David Rientjes <rient...@google.com>
Cc: Rik van Riel <r...@redhat.com> (commit_signer:5/10=50%)
Cc: Michel Lespinasse <wal...@google.com>
Cc: Shaohua Li <s...@kernel.org>
Cc: Jerome Marchand <jmarc...@redhat.com>
Cc: Mikulas Patocka <mpato...@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo....@lge.com>
---
include/linux/string.h | 1 +
mm/util.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index ac889c5..f29f9a0 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -114,6 +114,7 @@ void *memchr_inv(const void *s, int c, size_t n);
extern char *kstrdup(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 808f375..a8b731c 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -1,6 +1,7 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/ctype.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/sched.h>
@@ -63,6 +64,35 @@ 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
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
