php-src/ext/opcache/zend_accelerator_hash.c
2014-08-25 19:28:33 +02:00

225 lines
6.8 KiB
C

/*
+----------------------------------------------------------------------+
| Zend OPcache |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2014 The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 3.01 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.php.net/license/3_01.txt |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Andi Gutmans <andi@zend.com> |
| Zeev Suraski <zeev@zend.com> |
| Stanislav Malyshev <stas@zend.com> |
| Dmitry Stogov <dmitry@zend.com> |
+----------------------------------------------------------------------+
*/
#include "ZendAccelerator.h"
#include "zend_accelerator_hash.h"
#include "zend_hash.h"
#include "zend_shared_alloc.h"
/* Generated on an Octa-ALPHA 300MHz CPU & 2.5GB RAM monster */
static uint prime_numbers[] =
{5, 11, 19, 53, 107, 223, 463, 983, 1979, 3907, 7963, 16229, 32531, 65407, 130987, 262237, 524521, 1048793 };
static uint num_prime_numbers = sizeof(prime_numbers) / sizeof(uint);
void zend_accel_hash_clean(zend_accel_hash *accel_hash)
{
accel_hash->num_entries = 0;
accel_hash->num_direct_entries = 0;
memset(accel_hash->hash_table, 0, sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
}
void zend_accel_hash_init(zend_accel_hash *accel_hash, uint32_t hash_size)
{
uint i;
for (i=0; i<num_prime_numbers; i++) {
if (hash_size <= prime_numbers[i]) {
hash_size = prime_numbers[i];
break;
}
}
accel_hash->num_entries = 0;
accel_hash->num_direct_entries = 0;
accel_hash->max_num_entries = hash_size;
/* set up hash pointers table */
accel_hash->hash_table = zend_shared_alloc(sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
if (!accel_hash->hash_table) {
zend_accel_error(ACCEL_LOG_FATAL, "Insufficient shared memory!");
return;
}
/* set up hash values table */
accel_hash->hash_entries = zend_shared_alloc(sizeof(zend_accel_hash_entry)*accel_hash->max_num_entries);
if (!accel_hash->hash_entries) {
zend_accel_error(ACCEL_LOG_FATAL, "Insufficient shared memory!");
return;
}
memset(accel_hash->hash_table, 0, sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
}
/* Returns NULL if hash is full
* Returns pointer the actual hash entry on success
* key needs to be already allocated as it is not copied
*/
zend_accel_hash_entry* zend_accel_hash_update(zend_accel_hash *accel_hash, char *key, uint32_t key_length, zend_bool indirect, void *data)
{
zend_ulong hash_value;
zend_ulong index;
zend_accel_hash_entry *entry;
zend_accel_hash_entry *indirect_bucket = NULL;
if (indirect) {
indirect_bucket = (zend_accel_hash_entry*)data;
while (indirect_bucket->indirect) {
indirect_bucket = (zend_accel_hash_entry*)indirect_bucket->data;
}
}
hash_value = zend_inline_hash_func(key, key_length);
index = hash_value % accel_hash->max_num_entries;
/* try to see if the element already exists in the hash */
entry = accel_hash->hash_table[index];
while (entry) {
if (entry->hash_value == hash_value
&& entry->key_length == key_length
&& !memcmp(entry->key, key, key_length)) {
if (entry->indirect) {
if (indirect_bucket) {
entry->data = indirect_bucket;
} else {
((zend_accel_hash_entry*)entry->data)->data = data;
}
} else {
if (indirect_bucket) {
accel_hash->num_direct_entries--;
entry->data = indirect_bucket;
entry->indirect = 1;
} else {
entry->data = data;
}
}
return entry;
}
entry = entry->next;
}
/* Does not exist, add a new entry */
if (accel_hash->num_entries == accel_hash->max_num_entries) {
return NULL;
}
entry = &accel_hash->hash_entries[accel_hash->num_entries++];
if (indirect) {
entry->data = indirect_bucket;
entry->indirect = 1;
} else {
accel_hash->num_direct_entries++;
entry->data = data;
entry->indirect = 0;
}
entry->hash_value = hash_value;
entry->key = key;
entry->key_length = key_length;
entry->next = accel_hash->hash_table[index];
accel_hash->hash_table[index] = entry;
return entry;
}
/* Returns the data associated with key on success
* Returns NULL if data doesn't exist
*/
void* zend_accel_hash_find(zend_accel_hash *accel_hash, char *key, uint32_t key_length)
{
zend_ulong hash_value;
zend_ulong index;
zend_accel_hash_entry *entry;
hash_value = zend_inline_hash_func(key, key_length);
index = hash_value % accel_hash->max_num_entries;
entry = accel_hash->hash_table[index];
while (entry) {
if (entry->hash_value == hash_value
&& entry->key_length == key_length
&& !memcmp(entry->key, key, key_length)) {
if (entry->indirect) {
return ((zend_accel_hash_entry *) entry->data)->data;
} else {
return entry->data;
}
}
entry = entry->next;
}
return NULL;
}
/* Returns the hash entry associated with key on success
* Returns NULL if it doesn't exist
*/
zend_accel_hash_entry* zend_accel_hash_find_entry(zend_accel_hash *accel_hash, char *key, uint32_t key_length)
{
zend_ulong hash_value;
zend_ulong index;
zend_accel_hash_entry *entry;
hash_value = zend_inline_hash_func(key, key_length);
index = hash_value % accel_hash->max_num_entries;
entry = accel_hash->hash_table[index];
while (entry) {
if (entry->hash_value == hash_value
&& entry->key_length == key_length
&& !memcmp(entry->key, key, key_length)) {
if (entry->indirect) {
return (zend_accel_hash_entry *) entry->data;
} else {
return entry;
}
}
entry = entry->next;
}
return NULL;
}
int zend_accel_hash_unlink(zend_accel_hash *accel_hash, char *key, uint32_t key_length)
{
zend_ulong hash_value;
zend_ulong index;
zend_accel_hash_entry *entry, *last_entry=NULL;
hash_value = zend_inline_hash_func(key, key_length);
index = hash_value % accel_hash->max_num_entries;
entry = accel_hash->hash_table[index];
while (entry) {
if (entry->hash_value == hash_value
&& entry->key_length == key_length
&& !memcmp(entry->key, key, key_length)) {
if (!entry->indirect) {
accel_hash->num_direct_entries--;
}
if (last_entry) {
last_entry->next = entry->next;
} else {
accel_hash->hash_table[index] = entry->next;
}
return SUCCESS;
}
last_entry = entry;
entry = entry->next;
}
return FAILURE;
}