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 <me@xxxxxxxxxxxx>
---
builtin/gc.c | 4 +--
diff.c | 2 +-
notes.c | 2 +-
refs/packed-backend.c | 2 +-
string-list.c | 4 +--
string-list.h | 2 +-
t/helper/test-string-list.c | 4 +--
t/t0063-string-list.sh | 51 +++++++++++++++++++++++++++++++++++++
8 files changed, 61 insertions(+), 10 deletions(-)
diff --git a/builtin/gc.c b/builtin/gc.c
index edd98d35a5..f68e976704 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -1687,11 +1687,11 @@ static int get_schedule_cmd(const char **cmd, int *is_available)
if (is_available)
*is_available = 0;
- string_list_split_in_place(&list, testing, ',', -1);
+ string_list_split_in_place(&list, testing, ",", -1);
for_each_string_list_item(item, &list) {
struct string_list pair = STRING_LIST_INIT_NODUP;
- if (string_list_split_in_place(&pair, item->string, ':', 2) != 2)
+ if (string_list_split_in_place(&pair, item->string, ":", 2) != 2)
continue;
if (!strcmp(*cmd, pair.items[0].string)) {
diff --git a/diff.c b/diff.c
index 78b0fdd8ca..378a0248e1 100644
--- a/diff.c
+++ b/diff.c
@@ -134,7 +134,7 @@ static int parse_dirstat_params(struct diff_options *options, const char *params
int i;
if (*params_copy)
- string_list_split_in_place(¶ms, params_copy, ',', -1);
+ string_list_split_in_place(¶ms, params_copy, ",", -1);
for (i = 0; i < params.nr; i++) {
const char *p = params.items[i].string;
if (!strcmp(p, "changes")) {
diff --git a/notes.c b/notes.c
index 45fb7f22d1..eee806f626 100644
--- a/notes.c
+++ b/notes.c
@@ -963,7 +963,7 @@ void string_list_add_refs_from_colon_sep(struct string_list *list,
char *globs_copy = xstrdup(globs);
int i;
- string_list_split_in_place(&split, globs_copy, ':', -1);
+ string_list_split_in_place(&split, globs_copy, ":", -1);
string_list_remove_empty_items(&split, 0);
for (i = 0; i < split.nr; i++)
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;
diff --git a/string-list.c b/string-list.c
index db473f273e..5f5b60fe1c 100644
--- a/string-list.c
+++ b/string-list.c
@@ -301,7 +301,7 @@ int string_list_split(struct string_list *list, const char *string,
}
int string_list_split_in_place(struct string_list *list, char *string,
- int delim, int maxsplit)
+ const char *delim, int maxsplit)
{
int count = 0;
char *p = string, *end;
@@ -315,7 +315,7 @@ int string_list_split_in_place(struct string_list *list, char *string,
string_list_append(list, p);
return count;
}
- end = strchr(p, delim);
+ end = strpbrk(p, delim);
if (end) {
*end = '\0';
string_list_append(list, p);
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 */
diff --git a/t/helper/test-string-list.c b/t/helper/test-string-list.c
index 2123dda85b..63df88575c 100644
--- a/t/helper/test-string-list.c
+++ b/t/helper/test-string-list.c
@@ -62,7 +62,7 @@ int cmd__string_list(int argc, const char **argv)
struct string_list list = STRING_LIST_INIT_NODUP;
int i;
char *s = xstrdup(argv[2]);
- int delim = *argv[3];
+ const char *delim = argv[3];
int maxsplit = atoi(argv[4]);
i = string_list_split_in_place(&list, s, delim, maxsplit);
@@ -111,7 +111,7 @@ int cmd__string_list(int argc, const char **argv)
*/
if (sb.len && sb.buf[sb.len - 1] == '\n')
strbuf_setlen(&sb, sb.len - 1);
- string_list_split_in_place(&list, sb.buf, '\n', -1);
+ string_list_split_in_place(&list, sb.buf, "\n", -1);
string_list_sort(&list);
diff --git a/t/t0063-string-list.sh b/t/t0063-string-list.sh
index 46d4839194..1fee6d9010 100755
--- a/t/t0063-string-list.sh
+++ b/t/t0063-string-list.sh
@@ -18,6 +18,14 @@ test_split () {
"
}
+test_split_in_place() {
+ cat >expected &&
+ test_expect_success "split (in place) $1 at $2, max $3" "
+ test-tool string-list split_in_place '$1' '$2' '$3' >actual &&
+ test_cmp expected actual
+ "
+}
+
test_split "foo:bar:baz" ":" "-1" <<EOF
3
[0]: "foo"
@@ -61,6 +69,49 @@ test_split ":" ":" "-1" <<EOF
[1]: ""
EOF
+test_split_in_place "foo:;:bar:;:baz:;:" ":;" "-1" <<EOF
+10
+[0]: "foo"
+[1]: ""
+[2]: ""
+[3]: "bar"
+[4]: ""
+[5]: ""
+[6]: "baz"
+[7]: ""
+[8]: ""
+[9]: ""
+EOF
+
+test_split_in_place "foo:;:bar:;:baz" ":;" "0" <<EOF
+1
+[0]: "foo:;:bar:;:baz"
+EOF
+
+test_split_in_place "foo:;:bar:;:baz" ":;" "1" <<EOF
+2
+[0]: "foo"
+[1]: ";:bar:;:baz"
+EOF
+
+test_split_in_place "foo:;:bar:;:baz" ":;" "2" <<EOF
+3
+[0]: "foo"
+[1]: ""
+[2]: ":bar:;:baz"
+EOF
+
+test_split_in_place "foo:;:bar:;:" ":;" "-1" <<EOF
+7
+[0]: "foo"
+[1]: ""
+[2]: ""
+[3]: "bar"
+[4]: ""
+[5]: ""
+[6]: ""
+EOF
+
test_expect_success "test filter_string_list" '
test "x-" = "x$(test-tool string-list filter - y)" &&
test "x-" = "x$(test-tool string-list filter no y)" &&
--
2.40.0.380.gd2df7d2365
