From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Capella Subject: [PATCH v7 1/3] mm: add kstrdup_trimnl function Date: Tue, 4 Feb 2014 12:43:49 -0800 Message-ID: <1391546631-7715-2-git-send-email-sebastian.capella@linaro.org> References: <1391546631-7715-1-git-send-email-sebastian.capella@linaro.org> Return-path: In-Reply-To: <1391546631-7715-1-git-send-email-sebastian.capella@linaro.org> Sender: owner-linux-mm@kvack.org To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-pm@vger.kernel.org, linaro-kernel@lists.linaro.org, patches@linaro.org Cc: Sebastian Capella , Andrew Morton , Michel Lespinasse , Shaohua Li , Jerome Marchand , Mikulas Patocka , Joonsoo Kim , Joe Perches , David Rientjes , Alexey Dobriyan List-Id: linux-pm@vger.kernel.org kstrdup_trimnl creates a duplicate of the passed in null-terminated string. If a trailing newline is found, it is removed before duplicating. This is useful for strings coming from sysfs that often include trailing whitespace due to user input. Signed-off-by: Sebastian Capella Cc: Andrew Morton Cc: Rik van Riel (commit_signer:5/10=50%) Cc: Michel Lespinasse Cc: Shaohua Li Cc: Jerome Marchand Cc: Mikulas Patocka Cc: Joonsoo Kim Cc: Joe Perches Cc: David Rientjes Cc: Alexey Dobriyan --- include/linux/string.h | 1 + mm/util.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/include/linux/string.h b/include/linux/string.h index ac889c5..e7ec8c0 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 *kstrdup_trimnl(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..0bab867 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1,6 +1,7 @@ #include #include #include +#include #include #include #include @@ -63,6 +64,34 @@ char *kstrndup(const char *s, size_t max, gfp_t gfp) EXPORT_SYMBOL(kstrndup); /** + * kstrdup_trimnl - Copy a %NUL terminated string, removing one trailing + * newline if present. + * @s: the string to 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 a single trailing newline + * removed if present. + */ +char *kstrdup_trimnl(const char *s, gfp_t gfp) +{ + char *buf; + size_t len = strlen(s); + if (len >= 1 && s[len - 1] == '\n') + len--; + + buf = kmalloc_track_caller(len + 1, gfp); + if (!buf) + return NULL; + + memcpy(buf, s, len); + buf[len] = '\0'; + + return buf; +} +EXPORT_SYMBOL(kstrdup_trimnl); + +/** * kmemdup - duplicate region of memory * * @src: memory region to duplicate -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org