@matheusbsbs / matheus-bagliano / commits / e8a32e766f

string-list: replace negative index encoding with "exact_match" parameter

The "string_list_find_insert_index()" function is used to determine the correct insertion index for a new string within the string list. The function also doubles up to convey if the string is already existing in the list, this is done by returning a negative index "-1 -index". Users are expected to decode this information. This approach has several limitations: 1. It requires the callers to look into the detail of the function to understand how to decode the negative index encoding. 2. Using int for indices can cause overflow issues when dealing with large string lists. To address these limitations, change the function to return size_t for the index value and use a separate bool parameter to indicate whether the index refers to an existing entry or an insertion point. In some cases, the callers of "string_list_find_insert_index" only need the index position and don't care whether an exact match is found. However, "get_entry_index" currently requires a non-NULL "exact_match" parameter, forcing these callers to declare unnecessary variables. Let's allow callers to pass NULL for the "exact_match" parameter when they don't need this information, reducing unnecessary variable declarations in calling code. Signed-off-by: shejialuo <shejialuo@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

shejialuo committed Oct 6, 2025 at 14:32 UTC e8a32e766fe3f5e40fb8918a4d825e6d0b9aa272

5 files changed +15 -17

add-interactive.c

+4 -3

@@ -221,7 +221,8 @@ static void find_unique_prefixes(struct prefix_item_list *list)

221

222 static ssize_t find_unique(const char *string, struct prefix_item_list *list)

223 {

224 - int index = string_list_find_insert_index(&list->sorted, string, 1);

224 + bool exact_match;

225 + int index = string_list_find_insert_index(&list->sorted, string, &exact_match);

226 struct string_list_item *item;

227

228 if (list->items.nr != list->sorted.nr)

@@ -229,8 +230,8 @@ static ssize_t find_unique(const char *string, struct prefix_item_list *list)

230 " vs %"PRIuMAX")",

231 (uintmax_t)list->items.nr, (uintmax_t)list->sorted.nr);

232

232 - if (index < 0)

233 - item = list->sorted.items[-1 - index].util;

233 + if (exact_match)

234 + item = list->sorted.items[index].util;

235 else if (index > 0 &&

236 starts_with(list->sorted.items[index - 1].string, string))

237 return -1;

mailmap.c

+3 -4

@@ -243,10 +243,9 @@ void clear_mailmap(struct string_list *map)

243 static struct string_list_item *lookup_prefix(struct string_list *map,

244 const char *string, size_t len)

245 {

246 - int i = string_list_find_insert_index(map, string, 1);

247 - if (i < 0) {

248 - /* exact match */

249 - i = -1 - i;

246 + bool exact_match;

247 + int i = string_list_find_insert_index(map, string, &exact_match);

248 + if (exact_match) {

249 if (!string[len])

250 return &map->items[i];

251 /*

refs.c

+1 -1

@@ -1699,7 +1699,7 @@ const char *find_descendant_ref(const char *dirname,

1699 * with dirname (remember, dirname includes the trailing

1700 * slash) and is not in skip, then we have a conflict.

1701 */

1702 - for (pos = string_list_find_insert_index(extras, dirname, 0);

1702 + for (pos = string_list_find_insert_index(extras, dirname, NULL);

1703 pos < extras->nr; pos++) {

1704 const char *extra_refname = extras->items[pos].string;

1705

string-list.c

+6 -8

@@ -29,12 +29,14 @@ static size_t get_entry_index(const struct string_list *list, const char *string

29 else if (compare > 0)

30 left = middle + 1;

31 else {

32 - *exact_match = true;

32 + if (exact_match)

33 + *exact_match = true;

34 return middle;

35 }

36 }

37 - *exact_match = false;

38 + if (exact_match)

39 + *exact_match = false;

40 return right;

41 }

@@ -90,13 +92,9 @@ bool string_list_has_string(const struct string_list *list, const char *string)

92 }

94 int string_list_find_insert_index(const struct string_list *list, const char *string,

93 - int negative_existing_index)

95 + bool *exact_match)

96 {

95 - bool exact_match;

96 - int index = get_entry_index(list, string, &exact_match);

97 - if (exact_match)

98 - index = -1 - (negative_existing_index ? index : 0);

99 - return index;

97 + return get_entry_index(list, string, exact_match);

98 }

100 struct string_list_item *string_list_lookup(struct string_list *list, const char *string)

string-list.h

+1 -1

@@ -174,7 +174,7 @@ void string_list_remove_empty_items(struct string_list *list, int free_util);

174 /** Determine if the string_list has a given string or not. */

175 bool string_list_has_string(const struct string_list *list, const char *string);

176 int string_list_find_insert_index(const struct string_list *list, const char *string,

177 - int negative_existing_index);

177 + bool *exact_match);

178

179 /**

180 * Insert a new element to the string_list. The returned pointer can