From 1e66df3ee301209f4a38df097d7cc5cb9b367a3f Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Jul 2007 18:37:02 -0700 Subject: add kstrndup Add a kstrndup function, modelled on strndup. Like strndup this returns a string copied into its own allocated memory, but it copies no more than the specified number of bytes from the source. Remove private strndup() from irda code. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Chris Wright Cc: Andrew Morton Cc: Randy Dunlap Cc: YOSHIFUJI Hideaki Cc: Akinobu Mita Cc: Arnaldo Carvalho de Melo Cc: Al Viro Cc: Panagiotis Issaris Cc: Rene Scharfe --- mm/util.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) (limited to 'mm') diff --git a/mm/util.c b/mm/util.c index 78f3783bdcc8..bf340d806868 100644 --- a/mm/util.c +++ b/mm/util.c @@ -6,7 +6,6 @@ /** * kstrdup - allocate space for and copy an existing string - * * @s: the string to duplicate * @gfp: the GFP mask used in the kmalloc() call when allocating memory */ @@ -26,6 +25,30 @@ char *kstrdup(const char *s, gfp_t gfp) } EXPORT_SYMBOL(kstrdup); +/** + * kstrndup - allocate space for and copy an existing string + * @s: the string to duplicate + * @max: read at most @max chars from @s + * @gfp: the GFP mask used in the kmalloc() call when allocating memory + */ +char *kstrndup(const char *s, size_t max, gfp_t gfp) +{ + size_t len; + char *buf; + + if (!s) + return NULL; + + len = strnlen(s, max); + buf = kmalloc_track_caller(len+1, gfp); + if (buf) { + memcpy(buf, s, len); + buf[len] = '\0'; + } + return buf; +} +EXPORT_SYMBOL(kstrndup); + /** * kmemdup - duplicate region of memory * @@ -80,7 +103,6 @@ EXPORT_SYMBOL(krealloc); /* * strndup_user - duplicate an existing string from user space - * * @s: The string to duplicate * @n: Maximum number of bytes to copy, including the trailing NUL. */ -- cgit v1.2.2