1 /*
2 +----------------------------------------------------------------------+
3 | Zend OPcache |
4 +----------------------------------------------------------------------+
5 | Copyright (c) The PHP Group |
6 +----------------------------------------------------------------------+
7 | This source file is subject to version 3.01 of the PHP license, |
8 | that is bundled with this package in the file LICENSE, and is |
9 | available through the world-wide-web at the following url: |
10 | https://www.php.net/license/3_01.txt |
11 | If you did not receive a copy of the PHP license and are unable to |
12 | obtain it through the world-wide-web, please send a note to |
13 | license@php.net so we can mail you a copy immediately. |
14 +----------------------------------------------------------------------+
15 | Authors: Andi Gutmans <andi@php.net> |
16 | Zeev Suraski <zeev@php.net> |
17 | Stanislav Malyshev <stas@zend.com> |
18 | Dmitry Stogov <dmitry@php.net> |
19 +----------------------------------------------------------------------+
20 */
21
22 #include "ZendAccelerator.h"
23 #include "zend_accelerator_hash.h"
24 #include "zend_hash.h"
25 #include "zend_shared_alloc.h"
26
27 /* Generated on an Octa-ALPHA 300MHz CPU & 2.5GB RAM monster */
28 static const uint32_t prime_numbers[] =
29 {5, 11, 19, 53, 107, 223, 463, 983, 1979, 3907, 7963, 16229, 32531, 65407, 130987, 262237, 524521, 1048793 };
30 static const uint32_t num_prime_numbers = sizeof(prime_numbers) / sizeof(uint32_t);
31
zend_accel_hash_clean(zend_accel_hash * accel_hash)32 void zend_accel_hash_clean(zend_accel_hash *accel_hash)
33 {
34 accel_hash->num_entries = 0;
35 accel_hash->num_direct_entries = 0;
36 memset(accel_hash->hash_table, 0, sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
37 }
38
zend_accel_hash_init(zend_accel_hash * accel_hash,uint32_t hash_size)39 void zend_accel_hash_init(zend_accel_hash *accel_hash, uint32_t hash_size)
40 {
41 uint32_t i;
42
43 for (i=0; i<num_prime_numbers; i++) {
44 if (hash_size <= prime_numbers[i]) {
45 hash_size = prime_numbers[i];
46 break;
47 }
48 }
49
50 accel_hash->num_entries = 0;
51 accel_hash->num_direct_entries = 0;
52 accel_hash->max_num_entries = hash_size;
53
54 /* set up hash pointers table */
55 accel_hash->hash_table = zend_shared_alloc(sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
56 if (!accel_hash->hash_table) {
57 zend_accel_error_noreturn(ACCEL_LOG_FATAL, "Insufficient shared memory!");
58 return;
59 }
60
61 /* set up hash values table */
62 accel_hash->hash_entries = zend_shared_alloc(sizeof(zend_accel_hash_entry)*accel_hash->max_num_entries);
63 if (!accel_hash->hash_entries) {
64 zend_accel_error_noreturn(ACCEL_LOG_FATAL, "Insufficient shared memory!");
65 return;
66 }
67 memset(accel_hash->hash_table, 0, sizeof(zend_accel_hash_entry *)*accel_hash->max_num_entries);
68 }
69
70 /* Returns NULL if hash is full
71 * Returns pointer the actual hash entry on success
72 * key needs to be already allocated as it is not copied
73 */
zend_accel_hash_update(zend_accel_hash * accel_hash,zend_string * key,bool indirect,void * data)74 zend_accel_hash_entry* zend_accel_hash_update(zend_accel_hash *accel_hash, zend_string *key, bool indirect, void *data)
75 {
76 zend_ulong hash_value;
77 zend_ulong index;
78 zend_accel_hash_entry *entry;
79 zend_accel_hash_entry *indirect_bucket = NULL;
80
81 if (indirect) {
82 indirect_bucket = (zend_accel_hash_entry*)data;
83 while (indirect_bucket->indirect) {
84 indirect_bucket = (zend_accel_hash_entry*)indirect_bucket->data;
85 }
86 }
87
88 hash_value = zend_string_hash_val(key);
89 #ifndef ZEND_WIN32
90 hash_value ^= ZCG(root_hash);
91 #endif
92 index = hash_value % accel_hash->max_num_entries;
93
94 /* try to see if the element already exists in the hash */
95 entry = accel_hash->hash_table[index];
96 while (entry) {
97 if (entry->hash_value == hash_value
98 && zend_string_equals(entry->key, key)) {
99
100 if (entry->indirect) {
101 if (indirect_bucket) {
102 entry->data = indirect_bucket;
103 } else {
104 ((zend_accel_hash_entry*)entry->data)->data = data;
105 }
106 } else {
107 if (indirect_bucket) {
108 accel_hash->num_direct_entries--;
109 entry->data = indirect_bucket;
110 entry->indirect = 1;
111 } else {
112 entry->data = data;
113 }
114 }
115 return entry;
116 }
117 entry = entry->next;
118 }
119
120 /* Does not exist, add a new entry */
121 if (accel_hash->num_entries == accel_hash->max_num_entries) {
122 return NULL;
123 }
124
125 entry = &accel_hash->hash_entries[accel_hash->num_entries++];
126 if (indirect) {
127 entry->data = indirect_bucket;
128 entry->indirect = 1;
129 } else {
130 accel_hash->num_direct_entries++;
131 entry->data = data;
132 entry->indirect = 0;
133 }
134 entry->hash_value = hash_value;
135 entry->key = key;
136 entry->next = accel_hash->hash_table[index];
137 accel_hash->hash_table[index] = entry;
138 return entry;
139 }
140
zend_accel_hash_find_ex(zend_accel_hash * accel_hash,zend_string * key,int data)141 static zend_always_inline void* zend_accel_hash_find_ex(zend_accel_hash *accel_hash, zend_string *key, int data)
142 {
143 zend_ulong index;
144 zend_accel_hash_entry *entry;
145 zend_ulong hash_value;
146
147 hash_value = zend_string_hash_val(key);
148 #ifndef ZEND_WIN32
149 hash_value ^= ZCG(root_hash);
150 #endif
151 index = hash_value % accel_hash->max_num_entries;
152
153 entry = accel_hash->hash_table[index];
154 while (entry) {
155 if (entry->hash_value == hash_value
156 && zend_string_equals(entry->key, key)) {
157 if (entry->indirect) {
158 if (data) {
159 return ((zend_accel_hash_entry*)entry->data)->data;
160 } else {
161 return entry->data;
162 }
163 } else {
164 if (data) {
165 return entry->data;
166 } else {
167 return entry;
168 }
169 }
170 }
171 entry = entry->next;
172 }
173 return NULL;
174 }
175
176 /* Returns the data associated with key on success
177 * Returns NULL if data doesn't exist
178 */
zend_accel_hash_find(zend_accel_hash * accel_hash,zend_string * key)179 void* zend_accel_hash_find(zend_accel_hash *accel_hash, zend_string *key)
180 {
181 return zend_accel_hash_find_ex(accel_hash, key, 1);
182 }
183
184 /* Returns the hash entry associated with key on success
185 * Returns NULL if it doesn't exist
186 */
zend_accel_hash_find_entry(zend_accel_hash * accel_hash,zend_string * key)187 zend_accel_hash_entry* zend_accel_hash_find_entry(zend_accel_hash *accel_hash, zend_string *key)
188 {
189 return (zend_accel_hash_entry *)zend_accel_hash_find_ex(accel_hash, key, 0);
190 }
191
zend_accel_hash_unlink(zend_accel_hash * accel_hash,zend_string * key)192 int zend_accel_hash_unlink(zend_accel_hash *accel_hash, zend_string *key)
193 {
194 zend_ulong hash_value;
195 zend_ulong index;
196 zend_accel_hash_entry *entry, *last_entry=NULL;
197
198 hash_value = zend_string_hash_val(key);
199 #ifndef ZEND_WIN32
200 hash_value ^= ZCG(root_hash);
201 #endif
202 index = hash_value % accel_hash->max_num_entries;
203
204 entry = accel_hash->hash_table[index];
205 while (entry) {
206 if (entry->hash_value == hash_value
207 && zend_string_equals(entry->key, key)) {
208 if (!entry->indirect) {
209 accel_hash->num_direct_entries--;
210 }
211 if (last_entry) {
212 last_entry->next = entry->next;
213 } else {
214 accel_hash->hash_table[index] = entry->next;
215 }
216 return SUCCESS;
217 }
218 last_entry = entry;
219 entry = entry->next;
220 }
221 return FAILURE;
222 }
223