Commit 2af73182 authored by Nikias Bassen's avatar Nikias Bassen

bplist: Speed up plist_to_bin conversion for large plists

Using a better hashing algorithm and a larger hash table the conversion
is A LOT faster when processing large plists. Thanks to Xiao Deng for
reporting this issue and suggesting a fix.
parent 6ab7e301
......@@ -735,7 +735,7 @@ static unsigned int plist_data_hash(const void* key)
case PLIST_KEY:
case PLIST_STRING:
buff = data->strval;
size = strlen(buff);
size = data->length;
break;
case PLIST_DATA:
case PLIST_ARRAY:
......@@ -752,9 +752,12 @@ static unsigned int plist_data_hash(const void* key)
break;
}
//now perform hash
for (i = 0; i < size; buff++, i++)
hash = hash << 7 ^ (*buff);
// now perform hash using djb2 hashing algorithm
// see: http://www.cse.yorku.ca/~oz/hash.html
hash += 5381;
for (i = 0; i < size; buff++, i++) {
hash = ((hash << 5) + hash) + *buff;
}
return hash;
}
......
......@@ -24,7 +24,7 @@ hashtable_t* hash_table_new(hash_func_t hash_func, compare_func_t compare_func)
{
hashtable_t* ht = (hashtable_t*)malloc(sizeof(hashtable_t));
int i;
for (i = 0; i < 256; i++) {
for (i = 0; i < 4096; i++) {
ht->entries[i] = NULL;
}
ht->count = 0;
......@@ -38,7 +38,7 @@ void hash_table_destroy(hashtable_t *ht)
if (!ht) return;
int i = 0;
for (i = 0; i < 256; i++) {
for (i = 0; i < 4096; i++) {
if (ht->entries[i]) {
hashentry_t* e = ht->entries[i];
while (e) {
......@@ -58,7 +58,7 @@ void hash_table_insert(hashtable_t* ht, void *key, void *value)
unsigned int hash = ht->hash_func(key);
int idx0 = hash & 0xFF;
int idx0 = hash & 0xFFF;
// get the idx0 list
hashentry_t* e = ht->entries[idx0];
......@@ -93,7 +93,7 @@ void* hash_table_lookup(hashtable_t* ht, void *key)
if (!ht || !key) return NULL;
unsigned int hash = ht->hash_func(key);
int idx0 = hash & 0xFF;
int idx0 = hash & 0xFFF;
hashentry_t* e = ht->entries[idx0];
while (e) {
......
......@@ -32,7 +32,7 @@ typedef unsigned int(*hash_func_t)(const void* key);
typedef int (*compare_func_t)(const void *a, const void *b);
typedef struct hashtable_t {
hashentry_t *entries[256];
hashentry_t *entries[4096];
size_t count;
hash_func_t hash_func;
compare_func_t compare_func;
......
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