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author | André Goddard Rosa <andre.goddard@gmail.com> | 2009-12-14 18:01:04 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-12-15 08:53:32 -0800 |
commit | f653398c86a1c104f0992bd788dd4bb065449be4 (patch) | |
tree | 69cd79aaca48c2e1bdf9a48b968772347dbd5df2 /lib | |
parent | 4e62b0930223fe2f61094ceb1bbb31b3fe4251c2 (diff) | |
download | linux-f653398c86a1c104f0992bd788dd4bb065449be4.tar.gz linux-f653398c86a1c104f0992bd788dd4bb065449be4.tar.xz |
string: factorize skip_spaces and export it to be generally available
On the following sentence:
while (*s && isspace(*s))
s++;
If *s == 0, isspace() evaluates to ((_ctype[*s] & 0x20) != 0), which
evaluates to ((0x08 & 0x20) != 0) which equals to 0 as well.
If *s == 1, we depend on isspace() result anyway. In other words,
"a char equals zero is never a space", so remove this check.
Also, *s != 0 is most common case (non-null string).
Fixed const return as noticed by Jan Engelhardt and James Bottomley.
Fixed unnecessary extra cast on strstrip() as noticed by Jan Engelhardt.
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/string.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/lib/string.c b/lib/string.c index e96421ab9a9a..3a912a4e9a63 100644 --- a/lib/string.c +++ b/lib/string.c @@ -338,6 +338,20 @@ EXPORT_SYMBOL(strnchr); #endif /** + * skip_spaces - Removes leading whitespace from @s. + * @s: The string to be stripped. + * + * Returns a pointer to the first non-whitespace character in @s. + */ +char *skip_spaces(const char *str) +{ + while (isspace(*str)) + ++str; + return (char *)str; +} +EXPORT_SYMBOL(skip_spaces); + +/** * strstrip - Removes leading and trailing whitespace from @s. * @s: The string to be stripped. * @@ -360,10 +374,7 @@ char *strstrip(char *s) end--; *(end + 1) = '\0'; - while (*s && isspace(*s)) - s++; - - return s; + return skip_spaces(s); } EXPORT_SYMBOL(strstrip); |