xref: /PHP-7.2/Zend/zend_objects_API.c (revision bd6eabd6)
1 /*
2    +----------------------------------------------------------------------+
3    | Zend Engine                                                          |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1998-2018 Zend Technologies Ltd. (http://www.zend.com) |
6    +----------------------------------------------------------------------+
7    | This source file is subject to version 2.00 of the Zend 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    | http://www.zend.com/license/2_00.txt.                                |
11    | If you did not receive a copy of the Zend license and are unable to  |
12    | obtain it through the world-wide-web, please send a note to          |
13    | license@zend.com so we can mail you a copy immediately.              |
14    +----------------------------------------------------------------------+
15    | Authors: Andi Gutmans <andi@zend.com>                                |
16    |          Zeev Suraski <zeev@zend.com>                                |
17    |          Dmitry Stogov <dmitry@zend.com>                             |
18    +----------------------------------------------------------------------+
19 */
20 
21 /* $Id$ */
22 
23 #include "zend.h"
24 #include "zend_globals.h"
25 #include "zend_variables.h"
26 #include "zend_API.h"
27 #include "zend_objects_API.h"
28 
zend_objects_store_init(zend_objects_store * objects,uint32_t init_size)29 ZEND_API void zend_objects_store_init(zend_objects_store *objects, uint32_t init_size)
30 {
31 	objects->object_buckets = (zend_object **) emalloc(init_size * sizeof(zend_object*));
32 	objects->top = 1; /* Skip 0 so that handles are true */
33 	objects->size = init_size;
34 	objects->free_list_head = -1;
35 	memset(&objects->object_buckets[0], 0, sizeof(zend_object*));
36 }
37 
zend_objects_store_destroy(zend_objects_store * objects)38 ZEND_API void zend_objects_store_destroy(zend_objects_store *objects)
39 {
40 	efree(objects->object_buckets);
41 	objects->object_buckets = NULL;
42 }
43 
zend_objects_store_call_destructors(zend_objects_store * objects)44 ZEND_API void zend_objects_store_call_destructors(zend_objects_store *objects)
45 {
46 	EG(flags) |= EG_FLAGS_OBJECT_STORE_NO_REUSE;
47 	if (objects->top > 1) {
48 		uint32_t i;
49 		for (i = 1; i < objects->top; i++) {
50 			zend_object *obj = objects->object_buckets[i];
51 			if (IS_OBJ_VALID(obj)) {
52 				if (!(GC_FLAGS(obj) & IS_OBJ_DESTRUCTOR_CALLED)) {
53 					GC_FLAGS(obj) |= IS_OBJ_DESTRUCTOR_CALLED;
54 
55 					if (obj->handlers->dtor_obj
56 					 && (obj->handlers->dtor_obj != zend_objects_destroy_object
57 					  || obj->ce->destructor)) {
58 						GC_REFCOUNT(obj)++;
59 						obj->handlers->dtor_obj(obj);
60 						GC_REFCOUNT(obj)--;
61 					}
62 				}
63 			}
64 		}
65 	}
66 }
67 
zend_objects_store_mark_destructed(zend_objects_store * objects)68 ZEND_API void zend_objects_store_mark_destructed(zend_objects_store *objects)
69 {
70 	if (objects->object_buckets && objects->top > 1) {
71 		zend_object **obj_ptr = objects->object_buckets + 1;
72 		zend_object **end = objects->object_buckets + objects->top;
73 
74 		do {
75 			zend_object *obj = *obj_ptr;
76 
77 			if (IS_OBJ_VALID(obj)) {
78 				GC_FLAGS(obj) |= IS_OBJ_DESTRUCTOR_CALLED;
79 			}
80 			obj_ptr++;
81 		} while (obj_ptr != end);
82 	}
83 }
84 
zend_objects_store_free_object_storage(zend_objects_store * objects,zend_bool fast_shutdown)85 ZEND_API void zend_objects_store_free_object_storage(zend_objects_store *objects, zend_bool fast_shutdown)
86 {
87 	zend_object **obj_ptr, **end, *obj;
88 
89 	if (objects->top <= 1) {
90 		return;
91 	}
92 
93 	/* Free object contents, but don't free objects themselves, so they show up as leaks */
94 	end = objects->object_buckets + 1;
95 	obj_ptr = objects->object_buckets + objects->top;
96 
97 	if (fast_shutdown) {
98 		do {
99 			obj_ptr--;
100 			obj = *obj_ptr;
101 			if (IS_OBJ_VALID(obj)) {
102 				if (!(GC_FLAGS(obj) & IS_OBJ_FREE_CALLED)) {
103 					GC_FLAGS(obj) |= IS_OBJ_FREE_CALLED;
104 					if (obj->handlers->free_obj && obj->handlers->free_obj != zend_object_std_dtor) {
105 						GC_REFCOUNT(obj)++;
106 						obj->handlers->free_obj(obj);
107 						GC_REFCOUNT(obj)--;
108 					}
109 				}
110 			}
111 		} while (obj_ptr != end);
112 	} else {
113 		do {
114 			obj_ptr--;
115 			obj = *obj_ptr;
116 			if (IS_OBJ_VALID(obj)) {
117 				if (!(GC_FLAGS(obj) & IS_OBJ_FREE_CALLED)) {
118 					GC_FLAGS(obj) |= IS_OBJ_FREE_CALLED;
119 					if (obj->handlers->free_obj) {
120 						GC_REFCOUNT(obj)++;
121 						obj->handlers->free_obj(obj);
122 						GC_REFCOUNT(obj)--;
123 					}
124 				}
125 			}
126 		} while (obj_ptr != end);
127 	}
128 }
129 
130 
131 /* Store objects API */
132 
zend_objects_store_put(zend_object * object)133 ZEND_API void zend_objects_store_put(zend_object *object)
134 {
135 	int handle;
136 
137 	/* When in shutdown sequence - do not reuse previously freed handles, to make sure
138 	 * the dtors for newly created objects are called in zend_objects_store_call_destructors() loop
139 	 */
140 	if (EG(objects_store).free_list_head != -1 && EXPECTED(!(EG(flags) & EG_FLAGS_OBJECT_STORE_NO_REUSE))) {
141 		handle = EG(objects_store).free_list_head;
142 		EG(objects_store).free_list_head = GET_OBJ_BUCKET_NUMBER(EG(objects_store).object_buckets[handle]);
143 	} else {
144 		if (EG(objects_store).top == EG(objects_store).size) {
145 			uint32_t new_size = 2 * EG(objects_store).size;
146 			EG(objects_store).object_buckets = (zend_object **) erealloc(EG(objects_store).object_buckets, new_size * sizeof(zend_object*));
147 			/* Assign size after realloc, in case it fails */
148 			EG(objects_store).size = new_size;
149 		}
150 		handle = EG(objects_store).top++;
151 	}
152 	object->handle = handle;
153 	EG(objects_store).object_buckets[handle] = object;
154 }
155 
156 #define ZEND_OBJECTS_STORE_ADD_TO_FREE_LIST(handle)															\
157             SET_OBJ_BUCKET_NUMBER(EG(objects_store).object_buckets[handle], EG(objects_store).free_list_head);	\
158 			EG(objects_store).free_list_head = handle;
159 
zend_objects_store_del(zend_object * object)160 ZEND_API void zend_objects_store_del(zend_object *object) /* {{{ */
161 {
162 	/*	Make sure we hold a reference count during the destructor call
163 		otherwise, when the destructor ends the storage might be freed
164 		when the refcount reaches 0 a second time
165 	 */
166 	if (EG(objects_store).object_buckets &&
167 	    IS_OBJ_VALID(EG(objects_store).object_buckets[object->handle])) {
168 		if (GC_REFCOUNT(object) == 0) {
169 			if (!(GC_FLAGS(object) & IS_OBJ_DESTRUCTOR_CALLED)) {
170 				GC_FLAGS(object) |= IS_OBJ_DESTRUCTOR_CALLED;
171 
172 				if (object->handlers->dtor_obj
173 				 && (object->handlers->dtor_obj != zend_objects_destroy_object
174 				  || object->ce->destructor)) {
175 					GC_REFCOUNT(object)++;
176 					object->handlers->dtor_obj(object);
177 					GC_REFCOUNT(object)--;
178 				}
179 			}
180 
181 			if (GC_REFCOUNT(object) == 0) {
182 				uint32_t handle = object->handle;
183 				void *ptr;
184 
185 				EG(objects_store).object_buckets[handle] = SET_OBJ_INVALID(object);
186 				if (!(GC_FLAGS(object) & IS_OBJ_FREE_CALLED)) {
187 					GC_FLAGS(object) |= IS_OBJ_FREE_CALLED;
188 					if (object->handlers->free_obj) {
189 						GC_REFCOUNT(object)++;
190 						object->handlers->free_obj(object);
191 						GC_REFCOUNT(object)--;
192 					}
193 				}
194 				ptr = ((char*)object) - object->handlers->offset;
195 				GC_REMOVE_FROM_BUFFER(object);
196 				efree(ptr);
197 				ZEND_OBJECTS_STORE_ADD_TO_FREE_LIST(handle);
198 			}
199 		} else {
200 			GC_REFCOUNT(object)--;
201 		}
202 	}
203 }
204 /* }}} */
205 
zend_get_std_object_handlers(void)206 ZEND_API zend_object_handlers *zend_get_std_object_handlers(void)
207 {
208 	return &std_object_handlers;
209 }
210 
211 /*
212  * Local variables:
213  * tab-width: 4
214  * c-basic-offset: 4
215  * indent-tabs-mode: t
216  * End:
217  * vim600: sw=4 ts=4 fdm=marker
218  * vim<600: sw=4 ts=4
219  */
220