1 // Copyright 2016 The SwiftShader Authors. All Rights Reserved.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //    http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 // Object.hpp: Defines the Object base class that provides
16 // lifecycle support for GL objects using the traditional BindObject scheme, but
17 // that need to be reference counted for correct cross-context deletion.
18 
19 #ifndef gl_Object_hpp
20 #define gl_Object_hpp
21 
22 #include "common/debug.h"
23 
24 #include <set>
25 
26 typedef unsigned int GLuint;
27 
28 namespace gl
29 {
30 
31 class Object
32 {
33 public:
34 	Object();
35 
36 	virtual void addRef();
37 	virtual void release();
38 
hasSingleReference() const39 	inline bool hasSingleReference() const
40 	{
41 		return referenceCount == 1;
42 	}
43 
44 protected:
45 	virtual ~Object();
46 
47 	int dereference();
48 	void destroy();
49 
50 	volatile int referenceCount;
51 
52 #ifndef NDEBUG
53 public:
54 	static std::set<Object*> instances;   // For leak checking
55 #endif
56 };
57 
58 class NamedObject : public Object
59 {
60 public:
61 	explicit NamedObject(GLuint name);
62 	virtual ~NamedObject();
63 
64 	const GLuint name;
65 };
66 
67 template<class ObjectType>
68 class BindingPointer
69 {
70 public:
BindingPointer()71 	BindingPointer() : object(nullptr) { }
72 
BindingPointer(const BindingPointer<ObjectType> & other)73 	BindingPointer(const BindingPointer<ObjectType> &other) : object(nullptr)
74 	{
75 		operator=(other.object);
76 	}
77 
~BindingPointer()78 	~BindingPointer()
79 	{
80 		ASSERT(!object);   // Objects have to be released before the resource manager is destroyed, so they must be explicitly cleaned up. Assign null to all binding pointers to make the reference count go to zero.
81 	}
82 
operator =(ObjectType * newObject)83 	ObjectType *operator=(ObjectType *newObject)
84 	{
85 		if(newObject) newObject->addRef();
86 		if(object) object->release();
87 
88 		object = newObject;
89 
90 		return object;
91 	}
92 
operator =(const BindingPointer<ObjectType> & other)93 	ObjectType *operator=(const BindingPointer<ObjectType> &other)
94 	{
95 		return operator=(other.object);
96 	}
97 
operator ObjectType*() const98 	operator ObjectType*() const { return object; }
operator ->() const99 	ObjectType *operator->() const { return object; }
name() const100 	GLuint name() const { return object ? object->name : 0; }
operator !() const101 	bool operator!() const { return !object; }
102 
103 private:
104 	ObjectType *object;
105 };
106 
107 }
108 
109 #endif   // gl_Object_hpp
110