From 52acddf36c8cb3778ab2098a0d95cc2e375a4069 Mon Sep 17 00:00:00 2001 From: Taylor Blau Date: Mon, 24 Apr 2023 18:20:10 -0400 Subject: string-list: multi-delimiter `string_list_split_in_place()` Enhance `string_list_split_in_place()` to accept multiple characters as delimiters instead of a single character. Instead of using `strchr(2)` to locate the first occurrence of the given delimiter character, `string_list_split_in_place_multi()` uses `strcspn(2)` to move past the initial segment of characters comprised of any characters in the delimiting set. When only a single delimiting character is provided, `strpbrk(2)` (which is implemented with `strcspn(2)`) has equivalent performance to `strchr(2)`. Modern `strcspn(2)` implementations treat an empty delimiter or the singleton delimiter as a special case and fall back to calling strchrnul(). Both glibc[1] and musl[2] implement `strcspn(2)` this way. This change is one step to removing `strtok(2)` from the tree. Note that `string_list_split_in_place()` is not a strict replacement for `strtok()`, since it will happily turn sequential delimiter characters into empty entries in the resulting string_list. For example: string_list_split_in_place(&xs, "foo:;:bar:;:baz", ":;", -1) would yield a string list of: ["foo", "", "", "bar", "", "", "baz"] Callers that wish to emulate the behavior of strtok(2) more directly should call `string_list_remove_empty_items()` after splitting. To avoid regressions for the new multi-character delimter cases, update t0063 in this patch as well. [1]: https://sourceware.org/git/?p=glibc.git;a=blob;f=string/strcspn.c;hb=glibc-2.37#l35 [2]: https://git.musl-libc.org/cgit/musl/tree/src/string/strcspn.c?h=v1.2.3#n11 Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- string-list.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'string-list.h') diff --git a/string-list.h b/string-list.h index c7b0d5d000..77854840f7 100644 --- a/string-list.h +++ b/string-list.h @@ -270,5 +270,5 @@ int string_list_split(struct string_list *list, const char *string, * list->strdup_strings must *not* be set. */ int string_list_split_in_place(struct string_list *list, char *string, - int delim, int maxsplit); + const char *delim, int maxsplit); #endif /* STRING_LIST_H */ -- cgit v1.2.3