On Mon, 22 Jan 2024 15:40:09 +0800 Ye Bin <yebi...@huawei.com> wrote:
> str_has_suffix() is test string if ends with specify string. > > Signed-off-by: Ye Bin <yebi...@huawei.com> > --- > include/linux/string.h | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/include/linux/string.h b/include/linux/string.h > index 433c207a01da..e47e9597af27 100644 > --- a/include/linux/string.h > +++ b/include/linux/string.h > @@ -405,4 +405,24 @@ static __always_inline size_t str_has_prefix(const char > *str, const char *prefix > return strncmp(str, prefix, len) == 0 ? len : 0; > } > > +/** > + * str_has_suffix - Test if a string has a given suffix > + * @str: The string to test > + * @suffix: The string to see if @str ends with > + * > + * Returns: > + * * strlen(@suffix) if @str ends with @suffix > + * * 0 if @str does not end with @suffix > + */ > +static __always_inline size_t str_has_suffix(const char *str, const char > *suffix) > +{ > + size_t len = strlen(suffix); > + size_t str_len = strlen(str); > + > + if (len > str_len) > + return 0; > + > + return strncmp(str + str_len - len, suffix, len) == 0 ? len : 0; > +} I understand why you are returning the length of the suffix, as it matches str_has_prefix(). But as the user of this will likely need the length of the "str" too, we should either return the length of the string, or the index of where the suffix was found. /** [..] @index: The index into @str of where @suffix is if found (NULL to ignore) [..] */ static __always_inline size_t str_has_suffix(const char *str, const char *suffix, size_t *index) { size_t len = strlen(suffix); size_t str_len = strlen(str); if (len > str_len) return 0; if (index) *index = str_len - len; return strncmp(str + str_len - len, suffix, len) == 0 ? len : 0; } -- Steve > + > #endif /* _LINUX_STRING_H_ */