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-rw-r--r--third_party/git/hashmap.c307
1 files changed, 0 insertions, 307 deletions
diff --git a/third_party/git/hashmap.c b/third_party/git/hashmap.c
deleted file mode 100644
index d42f01ff5a..0000000000
--- a/third_party/git/hashmap.c
+++ /dev/null
@@ -1,307 +0,0 @@
-/*
- * Generic implementation of hash-based key value mappings.
- */
-#include "cache.h"
-#include "hashmap.h"
-
-#define FNV32_BASE ((unsigned int) 0x811c9dc5)
-#define FNV32_PRIME ((unsigned int) 0x01000193)
-
-unsigned int strhash(const char *str)
-{
-	unsigned int c, hash = FNV32_BASE;
-	while ((c = (unsigned char) *str++))
-		hash = (hash * FNV32_PRIME) ^ c;
-	return hash;
-}
-
-unsigned int strihash(const char *str)
-{
-	unsigned int c, hash = FNV32_BASE;
-	while ((c = (unsigned char) *str++)) {
-		if (c >= 'a' && c <= 'z')
-			c -= 'a' - 'A';
-		hash = (hash * FNV32_PRIME) ^ c;
-	}
-	return hash;
-}
-
-unsigned int memhash(const void *buf, size_t len)
-{
-	unsigned int hash = FNV32_BASE;
-	unsigned char *ucbuf = (unsigned char *) buf;
-	while (len--) {
-		unsigned int c = *ucbuf++;
-		hash = (hash * FNV32_PRIME) ^ c;
-	}
-	return hash;
-}
-
-unsigned int memihash(const void *buf, size_t len)
-{
-	unsigned int hash = FNV32_BASE;
-	unsigned char *ucbuf = (unsigned char *) buf;
-	while (len--) {
-		unsigned int c = *ucbuf++;
-		if (c >= 'a' && c <= 'z')
-			c -= 'a' - 'A';
-		hash = (hash * FNV32_PRIME) ^ c;
-	}
-	return hash;
-}
-
-/*
- * Incoporate another chunk of data into a memihash
- * computation.
- */
-unsigned int memihash_cont(unsigned int hash_seed, const void *buf, size_t len)
-{
-	unsigned int hash = hash_seed;
-	unsigned char *ucbuf = (unsigned char *) buf;
-	while (len--) {
-		unsigned int c = *ucbuf++;
-		if (c >= 'a' && c <= 'z')
-			c -= 'a' - 'A';
-		hash = (hash * FNV32_PRIME) ^ c;
-	}
-	return hash;
-}
-
-#define HASHMAP_INITIAL_SIZE 64
-/* grow / shrink by 2^2 */
-#define HASHMAP_RESIZE_BITS 2
-/* load factor in percent */
-#define HASHMAP_LOAD_FACTOR 80
-
-static void alloc_table(struct hashmap *map, unsigned int size)
-{
-	map->tablesize = size;
-	map->table = xcalloc(size, sizeof(struct hashmap_entry *));
-
-	/* calculate resize thresholds for new size */
-	map->grow_at = (unsigned int) ((uint64_t) size * HASHMAP_LOAD_FACTOR / 100);
-	if (size <= HASHMAP_INITIAL_SIZE)
-		map->shrink_at = 0;
-	else
-		/*
-		 * The shrink-threshold must be slightly smaller than
-		 * (grow-threshold / resize-factor) to prevent erratic resizing,
-		 * thus we divide by (resize-factor + 1).
-		 */
-		map->shrink_at = map->grow_at / ((1 << HASHMAP_RESIZE_BITS) + 1);
-}
-
-static inline int entry_equals(const struct hashmap *map,
-		const struct hashmap_entry *e1, const struct hashmap_entry *e2,
-		const void *keydata)
-{
-	return (e1 == e2) ||
-	       (e1->hash == e2->hash &&
-		!map->cmpfn(map->cmpfn_data, e1, e2, keydata));
-}
-
-static inline unsigned int bucket(const struct hashmap *map,
-		const struct hashmap_entry *key)
-{
-	return key->hash & (map->tablesize - 1);
-}
-
-int hashmap_bucket(const struct hashmap *map, unsigned int hash)
-{
-	return hash & (map->tablesize - 1);
-}
-
-static void rehash(struct hashmap *map, unsigned int newsize)
-{
-	unsigned int i, oldsize = map->tablesize;
-	struct hashmap_entry **oldtable = map->table;
-
-	alloc_table(map, newsize);
-	for (i = 0; i < oldsize; i++) {
-		struct hashmap_entry *e = oldtable[i];
-		while (e) {
-			struct hashmap_entry *next = e->next;
-			unsigned int b = bucket(map, e);
-			e->next = map->table[b];
-			map->table[b] = e;
-			e = next;
-		}
-	}
-	free(oldtable);
-}
-
-static inline struct hashmap_entry **find_entry_ptr(const struct hashmap *map,
-		const struct hashmap_entry *key, const void *keydata)
-{
-	struct hashmap_entry **e = &map->table[bucket(map, key)];
-	while (*e && !entry_equals(map, *e, key, keydata))
-		e = &(*e)->next;
-	return e;
-}
-
-static int always_equal(const void *unused_cmp_data,
-			const void *unused1,
-			const void *unused2,
-			const void *unused_keydata)
-{
-	return 0;
-}
-
-void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function,
-		const void *cmpfn_data, size_t initial_size)
-{
-	unsigned int size = HASHMAP_INITIAL_SIZE;
-
-	memset(map, 0, sizeof(*map));
-
-	map->cmpfn = equals_function ? equals_function : always_equal;
-	map->cmpfn_data = cmpfn_data;
-
-	/* calculate initial table size and allocate the table */
-	initial_size = (unsigned int) ((uint64_t) initial_size * 100
-			/ HASHMAP_LOAD_FACTOR);
-	while (initial_size > size)
-		size <<= HASHMAP_RESIZE_BITS;
-	alloc_table(map, size);
-
-	/*
-	 * Keep track of the number of items in the map and
-	 * allow the map to automatically grow as necessary.
-	 */
-	map->do_count_items = 1;
-}
-
-void hashmap_free(struct hashmap *map, int free_entries)
-{
-	if (!map || !map->table)
-		return;
-	if (free_entries) {
-		struct hashmap_iter iter;
-		struct hashmap_entry *e;
-		hashmap_iter_init(map, &iter);
-		while ((e = hashmap_iter_next(&iter)))
-			free(e);
-	}
-	free(map->table);
-	memset(map, 0, sizeof(*map));
-}
-
-void *hashmap_get(const struct hashmap *map, const void *key, const void *keydata)
-{
-	return *find_entry_ptr(map, key, keydata);
-}
-
-void *hashmap_get_next(const struct hashmap *map, const void *entry)
-{
-	struct hashmap_entry *e = ((struct hashmap_entry *) entry)->next;
-	for (; e; e = e->next)
-		if (entry_equals(map, entry, e, NULL))
-			return e;
-	return NULL;
-}
-
-void hashmap_add(struct hashmap *map, void *entry)
-{
-	unsigned int b = bucket(map, entry);
-
-	/* add entry */
-	((struct hashmap_entry *) entry)->next = map->table[b];
-	map->table[b] = entry;
-
-	/* fix size and rehash if appropriate */
-	if (map->do_count_items) {
-		map->private_size++;
-		if (map->private_size > map->grow_at)
-			rehash(map, map->tablesize << HASHMAP_RESIZE_BITS);
-	}
-}
-
-void *hashmap_remove(struct hashmap *map, const void *key, const void *keydata)
-{
-	struct hashmap_entry *old;
-	struct hashmap_entry **e = find_entry_ptr(map, key, keydata);
-	if (!*e)
-		return NULL;
-
-	/* remove existing entry */
-	old = *e;
-	*e = old->next;
-	old->next = NULL;
-
-	/* fix size and rehash if appropriate */
-	if (map->do_count_items) {
-		map->private_size--;
-		if (map->private_size < map->shrink_at)
-			rehash(map, map->tablesize >> HASHMAP_RESIZE_BITS);
-	}
-
-	return old;
-}
-
-void *hashmap_put(struct hashmap *map, void *entry)
-{
-	struct hashmap_entry *old = hashmap_remove(map, entry, NULL);
-	hashmap_add(map, entry);
-	return old;
-}
-
-void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter)
-{
-	iter->map = map;
-	iter->tablepos = 0;
-	iter->next = NULL;
-}
-
-void *hashmap_iter_next(struct hashmap_iter *iter)
-{
-	struct hashmap_entry *current = iter->next;
-	for (;;) {
-		if (current) {
-			iter->next = current->next;
-			return current;
-		}
-
-		if (iter->tablepos >= iter->map->tablesize)
-			return NULL;
-
-		current = iter->map->table[iter->tablepos++];
-	}
-}
-
-struct pool_entry {
-	struct hashmap_entry ent;
-	size_t len;
-	unsigned char data[FLEX_ARRAY];
-};
-
-static int pool_entry_cmp(const void *unused_cmp_data,
-			  const struct pool_entry *e1,
-			  const struct pool_entry *e2,
-			  const unsigned char *keydata)
-{
-	return e1->data != keydata &&
-	       (e1->len != e2->len || memcmp(e1->data, keydata, e1->len));
-}
-
-const void *memintern(const void *data, size_t len)
-{
-	static struct hashmap map;
-	struct pool_entry key, *e;
-
-	/* initialize string pool hashmap */
-	if (!map.tablesize)
-		hashmap_init(&map, (hashmap_cmp_fn) pool_entry_cmp, NULL, 0);
-
-	/* lookup interned string in pool */
-	hashmap_entry_init(&key, memhash(data, len));
-	key.len = len;
-	e = hashmap_get(&map, &key, data);
-	if (!e) {
-		/* not found: create it */
-		FLEX_ALLOC_MEM(e, data, data, len);
-		hashmap_entry_init(e, key.ent.hash);
-		e->len = len;
-		hashmap_add(&map, e);
-	}
-	return e->data;
-}