Permalink
Cannot retrieve contributors at this time
273 lines (242 sloc)
10.1 KB
| #ifndef STRING_LIST_H | |
| #define STRING_LIST_H | |
| /** | |
| * The string_list API offers a data structure and functions to handle | |
| * sorted and unsorted arrays of strings. A "sorted" list is one whose | |
| * entries are sorted by string value in the order specified by the `cmp` | |
| * member (`strcmp()` by default). | |
| * | |
| * The caller: | |
| * | |
| * . Allocates and clears a `struct string_list` variable. | |
| * | |
| * . Initializes the members. You might want to set the flag `strdup_strings` | |
| * if the strings should be strdup()ed. For example, this is necessary | |
| * when you add something like git_path("..."), since that function returns | |
| * a static buffer that will change with the next call to git_path(). | |
| * | |
| * If you need something advanced, you can manually malloc() the `items` | |
| * member (you need this if you add things later) and you should set the | |
| * `nr` and `alloc` members in that case, too. | |
| * | |
| * . Adds new items to the list, using `string_list_append`, | |
| * `string_list_append_nodup`, `string_list_insert`, | |
| * `string_list_split`, and/or `string_list_split_in_place`. | |
| * | |
| * . Can check if a string is in the list using `string_list_has_string` or | |
| * `unsorted_string_list_has_string` and get it from the list using | |
| * `string_list_lookup` for sorted lists. | |
| * | |
| * . Can sort an unsorted list using `string_list_sort`. | |
| * | |
| * . Can remove duplicate items from a sorted list using | |
| * `string_list_remove_duplicates`. | |
| * | |
| * . Can remove individual items of an unsorted list using | |
| * `unsorted_string_list_delete_item`. | |
| * | |
| * . Can remove items not matching a criterion from a sorted or unsorted | |
| * list using `filter_string_list`, or remove empty strings using | |
| * `string_list_remove_empty_items`. | |
| * | |
| * . Finally it should free the list using `string_list_clear`. | |
| * | |
| * Example: | |
| * | |
| * struct string_list list = STRING_LIST_INIT_NODUP; | |
| * int i; | |
| * | |
| * string_list_append(&list, "foo"); | |
| * string_list_append(&list, "bar"); | |
| * for (i = 0; i < list.nr; i++) | |
| * printf("%s\n", list.items[i].string) | |
| * | |
| * NOTE: It is more efficient to build an unsorted list and sort it | |
| * afterwards, instead of building a sorted list (`O(n log n)` instead of | |
| * `O(n^2)`). | |
| * | |
| * However, if you use the list to check if a certain string was added | |
| * already, you should not do that (using unsorted_string_list_has_string()), | |
| * because the complexity would be quadratic again (but with a worse factor). | |
| */ | |
| /** | |
| * Represents an item of the list. The `string` member is a pointer to the | |
| * string, and you may use the `util` member for any purpose, if you want. | |
| */ | |
| struct string_list_item { | |
| char *string; | |
| void *util; | |
| }; | |
| typedef int (*compare_strings_fn)(const char *, const char *); | |
| /** | |
| * Represents the list itself. | |
| * | |
| * . The array of items are available via the `items` member. | |
| * . The `nr` member contains the number of items stored in the list. | |
| * . The `alloc` member is used to avoid reallocating at every insertion. | |
| * You should not tamper with it. | |
| * . Setting the `strdup_strings` member to 1 will strdup() the strings | |
| * before adding them, see above. | |
| * . The `compare_strings_fn` member is used to specify a custom compare | |
| * function, otherwise `strcmp()` is used as the default function. | |
| */ | |
| struct string_list { | |
| struct string_list_item *items; | |
| unsigned int nr, alloc; | |
| unsigned int strdup_strings:1; | |
| compare_strings_fn cmp; /* NULL uses strcmp() */ | |
| }; | |
| #define STRING_LIST_INIT_NODUP { 0 } | |
| #define STRING_LIST_INIT_DUP { .strdup_strings = 1 } | |
| /* General functions which work with both sorted and unsorted lists. */ | |
| /** | |
| * Initialize the members of a string_list pointer in the same way as | |
| * the corresponding `STRING_LIST_INIT_NODUP` and | |
| * `STRING_LIST_INIT_DUP` macros. | |
| */ | |
| void string_list_init_nodup(struct string_list *list); | |
| void string_list_init_dup(struct string_list *list); | |
| /** | |
| * TODO remove: For compatibility with any in-flight older API users | |
| */ | |
| void string_list_init(struct string_list *list, int strdup_strings); | |
| /** Callback function type for for_each_string_list */ | |
| typedef int (*string_list_each_func_t)(struct string_list_item *, void *); | |
| /** | |
| * Apply `want` to each item in `list`, retaining only the ones for which | |
| * the function returns true. If `free_util` is true, call free() on | |
| * the util members of any items that have to be deleted. Preserve | |
| * the order of the items that are retained. | |
| */ | |
| void filter_string_list(struct string_list *list, int free_util, | |
| string_list_each_func_t want, void *cb_data); | |
| /** | |
| * Free a string_list. The `string` pointer of the items will be freed | |
| * in case the `strdup_strings` member of the string_list is set. The | |
| * second parameter controls if the `util` pointer of the items should | |
| * be freed or not. | |
| */ | |
| void string_list_clear(struct string_list *list, int free_util); | |
| /** | |
| * Callback type for `string_list_clear_func`. The string associated | |
| * with the util pointer is passed as the second argument | |
| */ | |
| typedef void (*string_list_clear_func_t)(void *p, const char *str); | |
| /** Call a custom clear function on each util pointer */ | |
| void string_list_clear_func(struct string_list *list, string_list_clear_func_t clearfunc); | |
| /** | |
| * Apply `func` to each item. If `func` returns nonzero, the | |
| * iteration aborts and the return value is propagated. | |
| */ | |
| int for_each_string_list(struct string_list *list, | |
| string_list_each_func_t func, void *cb_data); | |
| /** Iterate over each item, as a macro. */ | |
| #define for_each_string_list_item(item,list) \ | |
| for (item = (list)->items; \ | |
| item && item < (list)->items + (list)->nr; \ | |
| ++item) | |
| /** | |
| * Remove any empty strings from the list. If free_util is true, call | |
| * free() on the util members of any items that have to be deleted. | |
| * Preserve the order of the items that are retained. | |
| */ | |
| void string_list_remove_empty_items(struct string_list *list, int free_util); | |
| /* Use these functions only on sorted lists: */ | |
| /** Determine if the string_list has a given string or not. */ | |
| int string_list_has_string(const struct string_list *list, const char *string); | |
| int string_list_find_insert_index(const struct string_list *list, const char *string, | |
| int negative_existing_index); | |
| /** | |
| * Insert a new element to the string_list. The returned pointer can | |
| * be handy if you want to write something to the `util` pointer of | |
| * the string_list_item containing the just added string. If the given | |
| * string already exists the insertion will be skipped and the pointer | |
| * to the existing item returned. | |
| * | |
| * Since this function uses xrealloc() (which die()s if it fails) if the | |
| * list needs to grow, it is safe not to check the pointer. I.e. you may | |
| * write `string_list_insert(...)->util = ...;`. | |
| */ | |
| struct string_list_item *string_list_insert(struct string_list *list, const char *string); | |
| /** | |
| * Remove the given string from the sorted list. If the string | |
| * doesn't exist, the list is not altered. | |
| */ | |
| void string_list_remove(struct string_list *list, const char *string, | |
| int free_util); | |
| /** | |
| * Check if the given string is part of a sorted list. If it is part of the list, | |
| * return the corresponding string_list_item, NULL otherwise. | |
| */ | |
| struct string_list_item *string_list_lookup(struct string_list *list, const char *string); | |
| /* | |
| * Remove all but the first of consecutive entries with the same | |
| * string value. If free_util is true, call free() on the util | |
| * members of any items that have to be deleted. | |
| */ | |
| void string_list_remove_duplicates(struct string_list *sorted_list, int free_util); | |
| /* Use these functions only on unsorted lists: */ | |
| /** | |
| * Add string to the end of list. If list->strdup_string is set, then | |
| * string is copied; otherwise the new string_list_entry refers to the | |
| * input string. | |
| */ | |
| struct string_list_item *string_list_append(struct string_list *list, const char *string); | |
| /** | |
| * Like string_list_append(), except string is never copied. When | |
| * list->strdup_strings is set, this function can be used to hand | |
| * ownership of a malloc()ed string to list without making an extra | |
| * copy. | |
| */ | |
| struct string_list_item *string_list_append_nodup(struct string_list *list, char *string); | |
| /** | |
| * Sort the list's entries by string value in order specified by list->cmp | |
| * (strcmp() if list->cmp is NULL). | |
| */ | |
| void string_list_sort(struct string_list *list); | |
| /** | |
| * Like `string_list_has_string()` but for unsorted lists. Linear in | |
| * size of the list. | |
| */ | |
| int unsorted_string_list_has_string(struct string_list *list, const char *string); | |
| /** | |
| * Like `string_list_lookup()` but for unsorted lists. Linear in size | |
| * of the list. | |
| */ | |
| struct string_list_item *unsorted_string_list_lookup(struct string_list *list, | |
| const char *string); | |
| /** | |
| * Remove an item from a string_list. The `string` pointer of the | |
| * items will be freed in case the `strdup_strings` member of the | |
| * string_list is set. The third parameter controls if the `util` | |
| * pointer of the items should be freed or not. | |
| */ | |
| void unsorted_string_list_delete_item(struct string_list *list, int i, int free_util); | |
| /** | |
| * Split string into substrings on character `delim` and append the | |
| * substrings to `list`. The input string is not modified. | |
| * list->strdup_strings must be set, as new memory needs to be | |
| * allocated to hold the substrings. If maxsplit is non-negative, | |
| * then split at most maxsplit times. Return the number of substrings | |
| * appended to list. | |
| * | |
| * Examples: | |
| * string_list_split(l, "foo:bar:baz", ':', -1) -> ["foo", "bar", "baz"] | |
| * string_list_split(l, "foo:bar:baz", ':', 0) -> ["foo:bar:baz"] | |
| * string_list_split(l, "foo:bar:baz", ':', 1) -> ["foo", "bar:baz"] | |
| * string_list_split(l, "foo:bar:", ':', -1) -> ["foo", "bar", ""] | |
| * string_list_split(l, "", ':', -1) -> [""] | |
| * string_list_split(l, ":", ':', -1) -> ["", ""] | |
| */ | |
| int string_list_split(struct string_list *list, const char *string, | |
| int delim, int maxsplit); | |
| /* | |
| * Like string_list_split(), except that string is split in-place: the | |
| * delimiter characters in string are overwritten with NULs, and the | |
| * new string_list_items point into string (which therefore must not | |
| * be modified or freed while the string_list is in use). | |
| * list->strdup_strings must *not* be set. | |
| */ | |
| int string_list_split_in_place(struct string_list *list, char *string, | |
| int delim, int maxsplit); | |
| #endif /* STRING_LIST_H */ |