From d5f1fb53353edc38da326445267c1df0c9676df2 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Thu, 14 Jan 2010 10:53:55 +0800 Subject: lib: Introduce strnstr() It differs strstr() in that it limits the length to be searched in the first string. Signed-off-by: Li Zefan LKML-Reference: <4B4E8743.6030805@cn.fujitsu.com> Acked-by: Frederic Weisbecker Signed-off-by: Steven Rostedt --- lib/string.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) (limited to 'lib/string.c') diff --git a/lib/string.c b/lib/string.c index 9f75b4ec50b8..a1cdcfcc42d0 100644 --- a/lib/string.c +++ b/lib/string.c @@ -667,7 +667,7 @@ EXPORT_SYMBOL(memscan); */ char *strstr(const char *s1, const char *s2) { - int l1, l2; + size_t l1, l2; l2 = strlen(s2); if (!l2) @@ -684,6 +684,31 @@ char *strstr(const char *s1, const char *s2) EXPORT_SYMBOL(strstr); #endif +#ifndef __HAVE_ARCH_STRNSTR +/** + * strnstr - Find the first substring in a length-limited string + * @s1: The string to be searched + * @s2: The string to search for + * @len: the maximum number of characters to search + */ +char *strnstr(const char *s1, const char *s2, size_t len) +{ + size_t l1 = len, l2; + + l2 = strlen(s2); + if (!l2) + return (char *)s1; + while (l1 >= l2) { + l1--; + if (!memcmp(s1, s2, l2)) + return (char *)s1; + s1++; + } + return NULL; +} +EXPORT_SYMBOL(strnstr); +#endif + #ifndef __HAVE_ARCH_MEMCHR /** * memchr - Find a character in an area of memory. -- cgit v1.2.2 From a11d2b64e1f2556953120d516241243ea365f0ae Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Goddard=20Rosa?= Date: Fri, 5 Mar 2010 13:43:11 -0800 Subject: lib/string.c: simplify stricmp() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Removes 32 bytes on core2 with gcc 4.4.1: text data bss dec hex filename 3196 0 0 3196 c7c lib/string-BEFORE.o 3164 0 0 3164 c5c lib/string-AFTER.o Signed-off-by: André Goddard Rosa Cc: Joe Perches Cc: Frederic Weisbecker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/string.c | 34 +++++++++++++++------------------- 1 file changed, 15 insertions(+), 19 deletions(-) (limited to 'lib/string.c') diff --git a/lib/string.c b/lib/string.c index a1cdcfcc42d0..0f8624532082 100644 --- a/lib/string.c +++ b/lib/string.c @@ -36,25 +36,21 @@ int strnicmp(const char *s1, const char *s2, size_t len) /* Yes, Virginia, it had better be unsigned */ unsigned char c1, c2; - c1 = c2 = 0; - if (len) { - do { - c1 = *s1; - c2 = *s2; - s1++; - s2++; - if (!c1) - break; - if (!c2) - break; - if (c1 == c2) - continue; - c1 = tolower(c1); - c2 = tolower(c2); - if (c1 != c2) - break; - } while (--len); - } + if (!len) + return 0; + + do { + c1 = *s1++; + c2 = *s2++; + if (!c1 || !c2) + break; + if (c1 == c2) + continue; + c1 = tolower(c1); + c2 = tolower(c2); + if (c1 != c2) + break; + } while (--len); return (int)c1 - (int)c2; } EXPORT_SYMBOL(strnicmp); -- cgit v1.2.2 From d6a2eedfddcded92c8f9b0ac022a99c4134696b0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Goddard=20Rosa?= Date: Fri, 5 Mar 2010 13:43:12 -0800 Subject: lib/string.c: simplify strnstr() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: André Goddard Rosa Cc: Li Zefan Cc: Joe Perches Cc: Frederic Weisbecker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/string.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib/string.c') diff --git a/lib/string.c b/lib/string.c index 0f8624532082..f71bead1be3e 100644 --- a/lib/string.c +++ b/lib/string.c @@ -689,13 +689,13 @@ EXPORT_SYMBOL(strstr); */ char *strnstr(const char *s1, const char *s2, size_t len) { - size_t l1 = len, l2; + size_t l2; l2 = strlen(s2); if (!l2) return (char *)s1; - while (l1 >= l2) { - l1--; + while (len >= l2) { + len--; if (!memcmp(s1, s2, l2)) return (char *)s1; s1++; -- cgit v1.2.2