diff options
Diffstat (limited to 'lib/string.c')
-rw-r--r-- | lib/string.c | 57 |
1 files changed, 55 insertions, 2 deletions
diff --git a/lib/string.c b/lib/string.c index 01fad9b203e1..dc4a86341f91 100644 --- a/lib/string.c +++ b/lib/string.c @@ -360,7 +360,6 @@ char *strim(char *s) size_t size; char *end; - s = skip_spaces(s); size = strlen(s); if (!size) return s; @@ -370,7 +369,7 @@ char *strim(char *s) end--; *(end + 1) = '\0'; - return s; + return skip_spaces(s); } EXPORT_SYMBOL(strim); @@ -756,3 +755,57 @@ void *memchr(const void *s, int c, size_t n) } EXPORT_SYMBOL(memchr); #endif + +static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes) +{ + while (bytes) { + if (*start != value) + return (void *)start; + start++; + bytes--; + } + return NULL; +} + +/** + * memchr_inv - Find an unmatching character in an area of memory. + * @start: The memory area + * @c: Find a character other than c + * @bytes: The size of the area. + * + * returns the address of the first character other than @c, or %NULL + * if the whole buffer contains just @c. + */ +void *memchr_inv(const void *start, int c, size_t bytes) +{ + u8 value = c; + u64 value64; + unsigned int words, prefix; + + if (bytes <= 16) + return check_bytes8(start, value, bytes); + + value64 = value | value << 8 | value << 16 | value << 24; + value64 = (value64 & 0xffffffff) | value64 << 32; + prefix = 8 - ((unsigned long)start) % 8; + + if (prefix) { + u8 *r = check_bytes8(start, value, prefix); + if (r) + return r; + start += prefix; + bytes -= prefix; + } + + words = bytes / 8; + + while (words) { + if (*(u64 *)start != value64) + return check_bytes8(start, value, 8); + start += 8; + words--; + } + + return check_bytes8(start, value, bytes % 8); +} +EXPORT_SYMBOL(memchr_inv); |