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 --- refs/packed-backend.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'refs') diff --git a/refs/packed-backend.c b/refs/packed-backend.c index 1eba1015dd..cc903baa7e 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -650,7 +650,7 @@ static struct snapshot *create_snapshot(struct packed_ref_store *refs) snapshot->buf, snapshot->eof - snapshot->buf); - string_list_split_in_place(&traits, p, ' ', -1); + string_list_split_in_place(&traits, p, " ", -1); if (unsorted_string_list_has_string(&traits, "fully-peeled")) snapshot->peeled = PEELED_FULLY; -- cgit v1.2.3