[PATCH 1/5] string-list: fix sign compare warnings
- From
shejialuo <shejialuo@gmail.com>
- Date
- Apr 22, 2025, 14:54 UTC
- Message-ID
- <aAett8cJuDJ_FSdw@ArchLinux>
- In-Reply-To
- <aAetW0dan8S3Fljq@ArchLinux>
In "string-list.c", there are six warnings which are emitted by "Wsign-compare". And five warnings are caused by the loop iterator type mismatch, which could be simply fixed by changing the `int` type to `size_t` type.
However, for "string-list.c::add_entry" function, we compare the `index` of the `int` type with the `list->nr` of unsigned type. It seems that we could just simply convert the type of `index` from `int` to `size_t`. But actually this is a correct behavior.
We would set the `index` value by checking whether `insert_at` is -1. If not, we would set `index` to be `insert_at`, otherwise we would use "get_entry_index` to find the inserted position.
What if the caller passes a negative value except "-1", the compiler would convert the `index` to be a positive value which would make the `if` statement be false to avoid moving array. However, we would definitely encounter trouble when setting the inserted item.
And we only call "add_entry" in "string_list_insert" function, and we simply pass "-1" for "insert_at" parameter. So, we never use this parameter to insert element in a user specified position. Let's delete this parameter. If there is any requirement later, we may use a better way to do this. And then we could safely convert the index to be `size_t` when comparing.
Signed-off-by: shejialuo <shejialuo@gmail.com> --- string-list.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-)
diff --git a/string-list.c b/string-list.c index bf061fec56..a967421b60 100644 --- a/string-list.c +++ b/string-list.c @@ -1,5 +1,3 @@ -#define DISABLE_SIGN_COMPARE_WARNINGS - #include "git-compat-util.h" #include "string-list.h" @@ -41,16 +39,16 @@ static int get_entry_index(const struct string_list *list, const char *string, } /* returns -1-index if already exists */ -static int add_entry(int insert_at, struct string_list *list, const char *string) +static int add_entry(struct string_list *list, const char *string) { int exact_match = 0; - int index = insert_at != -1 ? insert_at : get_entry_index(list, string, &exact_match); + int index = get_entry_index(list, string, &exact_match); if (exact_match) return -1 - index; ALLOC_GROW(list->items, list->nr+1, list->alloc); - if (index < list->nr) + if ((size_t)index < list->nr) MOVE_ARRAY(list->items + index + 1, list->items + index, list->nr - index); list->items[index].string = list->strdup_strings ? @@ -63,7 +61,7 @@ static int add_entry(int insert_at, struct string_list *list, const char *string struct string_list_item *string_list_insert(struct string_list *list, const char *string) { - int index = add_entry(-1, list, string); + int index = add_entry(list, string); if (index < 0) index = -1 - index; @@ -116,7 +114,7 @@ struct string_list_item *string_list_lookup(struct string_list *list, const char void string_list_remove_duplicates(struct string_list *list, int free_util) { if (list->nr > 1) { - int src, dst; + size_t src, dst; compare_strings_fn cmp = list->cmp ? list->cmp : strcmp; for (src = dst = 1; src < list->nr; src++) { if (!cmp(list->items[dst - 1].string, list->items[src].string)) { @@ -134,8 +132,8 @@ void string_list_remove_duplicates(struct string_list *list, int free_util) int for_each_string_list(struct string_list *list, string_list_each_func_t fn, void *cb_data) { - int i, ret = 0; - for (i = 0; i < list->nr; i++) + int ret = 0; + for (size_t i = 0; i < list->nr; i++) if ((ret = fn(&list->items[i], cb_data))) break; return ret; @@ -144,8 +142,8 @@ int for_each_string_list(struct string_list *list, void filter_string_list(struct string_list *list, int free_util, string_list_each_func_t want, void *cb_data) { - int src, dst = 0; - for (src = 0; src < list->nr; src++) { + size_t dst = 0; + for (size_t src = 0; src < list->nr; src++) { if (want(&list->items[src], cb_data)) { list->items[dst++] = list->items[src]; } else { @@ -171,13 +169,12 @@ void string_list_remove_empty_items(struct string_list *list, int free_util) void string_list_clear(struct string_list *list, int free_util) { if (list->items) { - int i; if (list->strdup_strings) { - for (i = 0; i < list->nr; i++) + for (size_t i = 0; i < list->nr; i++) free(list->items[i].string); } if (free_util) { - for (i = 0; i < list->nr; i++) + for (size_t i = 0; i < list->nr; i++) free(list->items[i].util); } free(list->items); @@ -189,13 +186,12 @@ void string_list_clear(struct string_list *list, int free_util) void string_list_clear_func(struct string_list *list, string_list_clear_func_t clearfunc) { if (list->items) { - int i; if (clearfunc) { - for (i = 0; i < list->nr; i++) + for (size_t i = 0; i < list->nr; i++) clearfunc(list->items[i].util, list->items[i].string); } if (list->strdup_strings) { - for (i = 0; i < list->nr; i++) + for (size_t i = 0; i < list->nr; i++) free(list->items[i].string); } free(list->items);
-- 2.49.0