| #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 `strcmp()` order. |
| * |
| * 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 { NULL, 0, 0, 0, NULL } |
| #define STRING_LIST_INIT_DUP { NULL, 0, 0, 1, NULL } |
| |
| /* General functions which work with both sorted and unsorted lists. */ |
| |
| /** |
| * Initialize the members of the string_list, set `strdup_strings` |
| * member according to the value of the second parameter. |
| */ |
| 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); |
| |
| /** |
| * Dump a string_list to stdout, useful mainly for debugging |
| * purposes. It can take an optional header argument and it writes out |
| * the string-pointer pairs of the string_list, each one in its own |
| * line. |
| */ |
| void print_string_list(const struct string_list *p, const char *text); |
| |
| /** |
| * 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. |
| */ |
| extern 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 coresponding 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 `strcmp()` order. |
| */ |
| 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 */ |