Add a few functions to allow a string-list to be used as a stack: - string_list_last() lets a caller peek the string_list_item at the end of the string list. The caller needs to be aware that it is borrowing a pointer, which can become invalid if/when the string_list is resized. - string_list_pop() removes the string_list_item at the end of the string list. - there is no string_list_push(); string_list_append() can be used in its place. You can use them in this pattern: while (list.nr) { struct string_list_item *item = string_list_last(&list); work_on(item); string_list_pop(&list, free_util); } Helped-by: Junio C Hamano <gitster@xxxxxxxxx> Signed-off-by: Stefan Beller <sbeller@xxxxxxxxxx> --- I will be resending this series shortly, but it will not contain this patch, as I will have no need for these any longer. For the record, this is the final state of this patch. It may be useful on its own. Thanks, Stefan string-list.c | 14 ++++++++++++++ string-list.h | 15 +++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/string-list.c b/string-list.c index 771c4550980..04db2b537c0 100644 --- a/string-list.c +++ b/string-list.c @@ -80,6 +80,20 @@ void string_list_remove(struct string_list *list, const char *string, } } +void string_list_pop(struct string_list *list, int free_util) +{ + if (list->nr == 0) + BUG("tried to remove an item from empty string list"); + + if (list->strdup_strings) + free(list->items[list->nr - 1].string); + + if (free_util) + free(list->items[list->nr - 1].util); + + list->nr--; +} + int string_list_has_string(const struct string_list *list, const char *string) { int exact_match; diff --git a/string-list.h b/string-list.h index ff8f6094a33..15f2936e337 100644 --- a/string-list.h +++ b/string-list.h @@ -191,6 +191,21 @@ extern void string_list_remove(struct string_list *list, const char *string, */ struct string_list_item *string_list_lookup(struct string_list *list, const char *string); +/** + * Removes the last item from the list. + * The caller must ensure that the list is not empty. + */ +void string_list_pop(struct string_list *list, int free_util); + +/* + * Returns the last item of the list. As it returns the raw access, do not + * modify the list while holding onto the returned pointer. + */ +static inline struct string_list_item *string_list_last(struct string_list *list) +{ + return &list->items[list->nr - 1]; +} + /* * Remove all but the first of consecutive entries with the same * string value. If free_util is true, call free() on the util -- 2.19.0.444.g18242da7ef-goog