/* +----------------------------------------------------------------------+ | Copyright (c) The PHP Group | +----------------------------------------------------------------------+ | This source file is subject to version 2.00 of the Zend 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.zend.com/license/2_00.txt. | | If you did not receive a copy of the Zend license and are unable to | | obtain it through the world-wide-web, please send a note to | | license@zend.com so we can mail you a copy immediately. | +----------------------------------------------------------------------+ | Authors: krakjoe@php.net | +----------------------------------------------------------------------+ */ #ifndef ZEND_WEAKREFS_H #define ZEND_WEAKREFS_H #include "zend_alloc.h" BEGIN_EXTERN_C() extern ZEND_API zend_class_entry *zend_ce_weakref; void zend_register_weakref_ce(void); void zend_weakrefs_init(void); void zend_weakrefs_shutdown(void); ZEND_API void zend_weakrefs_notify(zend_object *object); ZEND_API zval *zend_weakrefs_hash_add(HashTable *ht, zend_object *key, zval *pData); ZEND_API zend_result zend_weakrefs_hash_del(HashTable *ht, zend_object *key); static zend_always_inline void *zend_weakrefs_hash_add_ptr(HashTable *ht, zend_object *key, void *ptr) { zval tmp, *zv; ZVAL_PTR(&tmp, ptr); if ((zv = zend_weakrefs_hash_add(ht, key, &tmp))) { return Z_PTR_P(zv); } else { return NULL; } } /* Because php uses the raw numbers as a hash function, raw pointers will lead to hash collisions. * We have a guarantee that the lowest ZEND_MM_ALIGNED_OFFSET_LOG2 bits of a pointer are zero. * * E.g. On most 64-bit platforms, pointers are aligned to 8 bytes, so the least significant 3 bits are always 0 and can be discarded. * * NOTE: This function is only used for EG(weakrefs) and zend_weakmap->ht. * It is not used for the HashTable instances associated with ZEND_WEAKREF_TAG_HT tags (created in zend_weakref_register, which uses ZEND_WEAKREF_ENCODE instead). * The ZEND_WEAKREF_TAG_HT instances are used to disambiguate between multiple weak references to the same zend_object. */ static zend_always_inline zend_ulong zend_object_to_weakref_key(const zend_object *object) { ZEND_ASSERT(((uintptr_t)object) % ZEND_MM_ALIGNMENT == 0); return ((uintptr_t) object) >> ZEND_MM_ALIGNMENT_LOG2; } static zend_always_inline zend_object *zend_weakref_key_to_object(zend_ulong key) { return (zend_object *) (((uintptr_t) key) << ZEND_MM_ALIGNMENT_LOG2); } END_EXTERN_C() #endif