From ba472ab2f1b1af8ccb9768859fa56e2d136a759e Mon Sep 17 00:00:00 2001 From: shejialuo Date: Sun, 29 Jun 2025 12:27:41 +0800 Subject: string-list: fix sign compare warnings for loop iterator There are a couple of "-Wsign-compare" warnings in "string-list.c". Fix trivial ones that result from a mismatched loop iterator type. There is a single warning left after these fixes. This warning needs a bit more care and is thus handled in subsequent commits. Signed-off-by: shejialuo Signed-off-by: Junio C Hamano --- string-list.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) (limited to 'string-list.c') diff --git a/string-list.c b/string-list.c index bf061fec56..801ece0cba 100644 --- a/string-list.c +++ b/string-list.c @@ -116,9 +116,9 @@ 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 dst = 1; compare_strings_fn cmp = list->cmp ? list->cmp : strcmp; - for (src = dst = 1; src < list->nr; src++) { + for (size_t src = 1; src < list->nr; src++) { if (!cmp(list->items[dst - 1].string, list->items[src].string)) { if (list->strdup_strings) free(list->items[src].string); @@ -134,8 +134,8 @@ 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 +144,8 @@ 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 +171,12 @@ 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 +188,12 @@ 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); -- cgit v1.3 From 394e063bf9ab88f2117fe8bb8115809420ecfeda Mon Sep 17 00:00:00 2001 From: shejialuo Date: Sun, 29 Jun 2025 12:27:49 +0800 Subject: string-list: remove unused "insert_at" parameter from add_entry In "add_entry", we accept "insert_at" parameter which must be either -1 (auto) or between 0 and `list->nr` inclusive. Any other value is invalid. When caller specify any invalid "insert_at" value, we won't check the range and move the element, which would definitely cause the trouble. However, we only use "add_entry" in "string_list_insert" function and we always pass the "-1" for "insert_at" parameter. So, we never use this parameter to insert element in a user specified position. And we should know why there is such code path in the first place. We used to have another function "string_list_insert_at_index()", which uses the extra "insert_at" parameter. And in f8c4ab611a (string_list: remove string_list_insert_at_index() from its API, 2014-11-24), we remove this function but we don't clean all the code path. Let's simply delete this parameter as we'd better use "strmap" for such functionality. Signed-off-by: shejialuo Signed-off-by: Junio C Hamano --- string-list.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'string-list.c') diff --git a/string-list.c b/string-list.c index 801ece0cba..8540c29bc9 100644 --- a/string-list.c +++ b/string-list.c @@ -41,10 +41,10 @@ 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; @@ -63,7 +63,7 @@ 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; -- cgit v1.3 From 885becd9c4aec6c3764b4c701baf41853b49899e Mon Sep 17 00:00:00 2001 From: shejialuo Date: Sun, 29 Jun 2025 12:27:57 +0800 Subject: string-list: return index directly when inserting an existing element When inserting an existing element, "add_entry" would convert "index" value to "-1-index" to indicate the caller that this element is in the list already. However, in "string_list_insert", we would simply convert this to the original positive index without any further action. In 8fd2cb4069 (Extract helper bits from c-merge-recursive work, 2006-07-25), we create "path-list.c" and then introduce above code path. Let's directly return the index as we don't care about whether the element is in the list by using "add_entry". In the future, if we want to let "add_entry" tell the caller, we may add "int *exact_match" parameter to "add_entry" instead of converting the index to negative to indicate. Signed-off-by: shejialuo Signed-off-by: Junio C Hamano --- string-list.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'string-list.c') diff --git a/string-list.c b/string-list.c index 8540c29bc9..171cef5dbb 100644 --- a/string-list.c +++ b/string-list.c @@ -40,14 +40,13 @@ static int get_entry_index(const struct string_list *list, const char *string, return right; } -/* returns -1-index if already exists */ static int add_entry(struct string_list *list, const char *string) { int exact_match = 0; int index = get_entry_index(list, string, &exact_match); if (exact_match) - return -1 - index; + return index; ALLOC_GROW(list->items, list->nr+1, list->alloc); if (index < list->nr) @@ -65,9 +64,6 @@ struct string_list_item *string_list_insert(struct string_list *list, const char { int index = add_entry(list, string); - if (index < 0) - index = -1 - index; - return list->items + index; } -- cgit v1.3 From 67cfd2924d099b3316ddf579ba7c11fdc29ad2b6 Mon Sep 17 00:00:00 2001 From: shejialuo Date: Sun, 29 Jun 2025 12:28:06 +0800 Subject: string-list: enable sign compare warnings check In "add_entry", we call "get_entry_index" function to get the inserted position. However, as the return type of "get_entry_index" function is `int`, there is a sign compare warning when comparing the `index` with the `list-nr` of unsigned type. "get_entry_index" would always return unsigned index. However, the current binary search algorithm initializes "left" to be "-1", which necessitates the use of signed `int` return type. The reason why we need to assign "left" to be "-1" is that in the `while` loop, we increment "left" by 1 to determine whether the loop should end. This design choice, while functional, forces us to use signed arithmetic throughout the function. To resolve this sign comparison issue, let's modify the binary search algorithm with the following approach: 1. Initialize "left" to 0 instead of -1 2. Use `left < right` as the loop termination condition instead of `left + 1 < right` 3. When searching the right part, set `left = middle + 1` instead of `middle` Then, we could delete "#define DISABLE_SIGN_COMPARE_WARNING" to enable sign warnings check for "string-list". Signed-off-by: shejialuo Signed-off-by: Junio C Hamano --- string-list.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) (limited to 'string-list.c') diff --git a/string-list.c b/string-list.c index 171cef5dbb..53faaa8420 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" @@ -17,19 +15,19 @@ void string_list_init_dup(struct string_list *list) /* if there is no exact match, point to the index where the entry could be * inserted */ -static int get_entry_index(const struct string_list *list, const char *string, - int *exact_match) +static size_t get_entry_index(const struct string_list *list, const char *string, + int *exact_match) { - int left = -1, right = list->nr; + size_t left = 0, right = list->nr; compare_strings_fn cmp = list->cmp ? list->cmp : strcmp; - while (left + 1 < right) { - int middle = left + (right - left) / 2; + while (left < right) { + size_t middle = left + (right - left) / 2; int compare = cmp(string, list->items[middle].string); if (compare < 0) right = middle; else if (compare > 0) - left = middle; + left = middle + 1; else { *exact_match = 1; return middle; @@ -40,10 +38,10 @@ static int get_entry_index(const struct string_list *list, const char *string, return right; } -static int add_entry(struct string_list *list, const char *string) +static size_t add_entry(struct string_list *list, const char *string) { int exact_match = 0; - int index = get_entry_index(list, string, &exact_match); + size_t index = get_entry_index(list, string, &exact_match); if (exact_match) return index; @@ -62,7 +60,7 @@ static int add_entry(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(list, string); + size_t index = add_entry(list, string); return list->items + index; } -- cgit v1.3