git/string-list.c
Michael Haggerty f103f95b11 string_list: add a function string_list_longest_prefix()
Add a function that finds the longest string from a string_list that
is a prefix of a given string.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12 11:43:25 -07:00

314 lines
7.2 KiB
C

#include "cache.h"
#include "string-list.h"
/* 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)
{
int left = -1, right = list->nr;
while (left + 1 < right) {
int middle = (left + right) / 2;
int compare = strcmp(string, list->items[middle].string);
if (compare < 0)
right = middle;
else if (compare > 0)
left = middle;
else {
*exact_match = 1;
return middle;
}
}
*exact_match = 0;
return right;
}
/* returns -1-index if already exists */
static int add_entry(int insert_at, 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);
if (exact_match)
return -1 - index;
if (list->nr + 1 >= list->alloc) {
list->alloc += 32;
list->items = xrealloc(list->items, list->alloc
* sizeof(struct string_list_item));
}
if (index < list->nr)
memmove(list->items + index + 1, list->items + index,
(list->nr - index)
* sizeof(struct string_list_item));
list->items[index].string = list->strdup_strings ?
xstrdup(string) : (char *)string;
list->items[index].util = NULL;
list->nr++;
return index;
}
struct string_list_item *string_list_insert(struct string_list *list, const char *string)
{
return string_list_insert_at_index(list, -1, string);
}
struct string_list_item *string_list_insert_at_index(struct string_list *list,
int insert_at, const char *string)
{
int index = add_entry(insert_at, list, string);
if (index < 0)
index = -1 - index;
return list->items + index;
}
int string_list_has_string(const struct string_list *list, const char *string)
{
int exact_match;
get_entry_index(list, string, &exact_match);
return exact_match;
}
int string_list_find_insert_index(const struct string_list *list, const char *string,
int negative_existing_index)
{
int exact_match;
int index = get_entry_index(list, string, &exact_match);
if (exact_match)
index = -1 - (negative_existing_index ? index : 0);
return index;
}
struct string_list_item *string_list_lookup(struct string_list *list, const char *string)
{
int exact_match, i = get_entry_index(list, string, &exact_match);
if (!exact_match)
return NULL;
return list->items + i;
}
void string_list_remove_duplicates(struct string_list *list, int free_util)
{
if (list->nr > 1) {
int src, dst;
for (src = dst = 1; src < list->nr; src++) {
if (!strcmp(list->items[dst - 1].string, list->items[src].string)) {
if (list->strdup_strings)
free(list->items[src].string);
if (free_util)
free(list->items[src].util);
} else
list->items[dst++] = list->items[src];
}
list->nr = dst;
}
}
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++)
if ((ret = fn(&list->items[i], cb_data)))
break;
return ret;
}
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++) {
if (want(&list->items[src], cb_data)) {
list->items[dst++] = list->items[src];
} else {
if (list->strdup_strings)
free(list->items[src].string);
if (free_util)
free(list->items[src].util);
}
}
list->nr = dst;
}
char *string_list_longest_prefix(const struct string_list *prefixes,
const char *string)
{
int i, max_len = -1;
char *retval = NULL;
for (i = 0; i < prefixes->nr; i++) {
char *prefix = prefixes->items[i].string;
if (!prefixcmp(string, prefix)) {
int len = strlen(prefix);
if (len > max_len) {
retval = prefix;
max_len = len;
}
}
}
return retval;
}
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++)
free(list->items[i].string);
}
if (free_util) {
for (i = 0; i < list->nr; i++)
free(list->items[i].util);
}
free(list->items);
}
list->items = NULL;
list->nr = list->alloc = 0;
}
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++)
clearfunc(list->items[i].util, list->items[i].string);
}
if (list->strdup_strings) {
for (i = 0; i < list->nr; i++)
free(list->items[i].string);
}
free(list->items);
}
list->items = NULL;
list->nr = list->alloc = 0;
}
void print_string_list(const struct string_list *p, const char *text)
{
int i;
if ( text )
printf("%s\n", text);
for (i = 0; i < p->nr; i++)
printf("%s:%p\n", p->items[i].string, p->items[i].util);
}
struct string_list_item *string_list_append_nodup(struct string_list *list,
char *string)
{
struct string_list_item *retval;
ALLOC_GROW(list->items, list->nr + 1, list->alloc);
retval = &list->items[list->nr++];
retval->string = string;
retval->util = NULL;
return retval;
}
struct string_list_item *string_list_append(struct string_list *list,
const char *string)
{
return string_list_append_nodup(
list,
list->strdup_strings ? xstrdup(string) : (char *)string);
}
static int cmp_items(const void *a, const void *b)
{
const struct string_list_item *one = a;
const struct string_list_item *two = b;
return strcmp(one->string, two->string);
}
void sort_string_list(struct string_list *list)
{
qsort(list->items, list->nr, sizeof(*list->items), cmp_items);
}
struct string_list_item *unsorted_string_list_lookup(struct string_list *list,
const char *string)
{
int i;
for (i = 0; i < list->nr; i++)
if (!strcmp(string, list->items[i].string))
return list->items + i;
return NULL;
}
int unsorted_string_list_has_string(struct string_list *list,
const char *string)
{
return unsorted_string_list_lookup(list, string) != NULL;
}
void unsorted_string_list_delete_item(struct string_list *list, int i, int free_util)
{
if (list->strdup_strings)
free(list->items[i].string);
if (free_util)
free(list->items[i].util);
list->items[i] = list->items[list->nr-1];
list->nr--;
}
int string_list_split(struct string_list *list, const char *string,
int delim, int maxsplit)
{
int count = 0;
const char *p = string, *end;
if (!list->strdup_strings)
die("internal error in string_list_split(): "
"list->strdup_strings must be set");
for (;;) {
count++;
if (maxsplit >= 0 && count > maxsplit) {
string_list_append(list, p);
return count;
}
end = strchr(p, delim);
if (end) {
string_list_append_nodup(list, xmemdupz(p, end - p));
p = end + 1;
} else {
string_list_append(list, p);
return count;
}
}
}
int string_list_split_in_place(struct string_list *list, char *string,
int delim, int maxsplit)
{
int count = 0;
char *p = string, *end;
if (list->strdup_strings)
die("internal error in string_list_split_in_place(): "
"list->strdup_strings must not be set");
for (;;) {
count++;
if (maxsplit >= 0 && count > maxsplit) {
string_list_append(list, p);
return count;
}
end = strchr(p, delim);
if (end) {
*end = '\0';
string_list_append(list, p);
p = end + 1;
} else {
string_list_append(list, p);
return count;
}
}
}