1/*
2 ** Copyright 2007, The Android Open Source Project
3 **
4 ** Licensed under the Apache License, Version 2.0 (the "License");
5 ** you may not use this file except in compliance with the License.
6 ** You may obtain a copy of the License at
7 **
8 **     http://www.apache.org/licenses/LICENSE-2.0
9 **
10 ** Unless required by applicable law or agreed to in writing, software
11 ** distributed under the License is distributed on an "AS IS" BASIS,
12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 ** See the License for the specific language governing permissions and
14 ** limitations under the License.
15 */
16
17#ifndef ANDROID_EGL_DISPLAY_H
18#define ANDROID_EGL_DISPLAY_H
19
20
21#include <ctype.h>
22#include <stdint.h>
23#include <stdlib.h>
24
25#include <EGL/egl.h>
26#include <EGL/eglext.h>
27
28#include <cutils/compiler.h>
29#include <utils/SortedVector.h>
30#include <utils/threads.h>
31#include <utils/String8.h>
32
33#include "egldefs.h"
34#include "../hooks.h"
35
36// ----------------------------------------------------------------------------
37namespace android {
38// ----------------------------------------------------------------------------
39
40class egl_object_t;
41class egl_context_t;
42class egl_connection_t;
43
44// ----------------------------------------------------------------------------
45
46class EGLAPI egl_display_t { // marked as EGLAPI for testing purposes
47    static egl_display_t sDisplay[NUM_DISPLAYS];
48    EGLDisplay getDisplay(EGLNativeDisplayType display);
49    void loseCurrentImpl(egl_context_t * cur_c);
50
51public:
52    enum {
53        NOT_INITIALIZED = 0,
54        INITIALIZED     = 1,
55        TERMINATED      = 2
56    };
57
58    egl_display_t();
59    ~egl_display_t();
60
61    EGLBoolean initialize(EGLint *major, EGLint *minor);
62    EGLBoolean terminate();
63
64    // add object to this display's list
65    void addObject(egl_object_t* object);
66    // remove object from this display's list
67    void removeObject(egl_object_t* object);
68    // add reference to this object. returns true if this is a valid object.
69    bool getObject(egl_object_t* object) const;
70
71    // These notifications allow the display to keep track of how many window
72    // surfaces exist, which it uses to decide whether to hibernate the
73    // underlying EGL implementation. They can be called by any thread without
74    // holding a lock, but must be called via egl_display_ptr to ensure
75    // proper hibernate/wakeup sequencing. If a surface destruction triggers
76    // hibernation, hibernation will be delayed at least until the calling
77    // thread's egl_display_ptr is destroyed.
78    void onWindowSurfaceCreated() {
79        mHibernation.incWakeCount(HibernationMachine::STRONG);
80    }
81    void onWindowSurfaceDestroyed() {
82        mHibernation.decWakeCount(HibernationMachine::STRONG);
83    }
84
85    static egl_display_t* get(EGLDisplay dpy);
86    static EGLDisplay getFromNativeDisplay(EGLNativeDisplayType disp);
87
88    EGLBoolean makeCurrent(egl_context_t* c, egl_context_t* cur_c,
89            EGLSurface draw, EGLSurface read, EGLContext ctx,
90            EGLSurface impl_draw, EGLSurface impl_read, EGLContext impl_ctx);
91    static void loseCurrent(egl_context_t * cur_c);
92
93    inline bool isReady() const { return (refs > 0); }
94    inline bool isValid() const { return magic == '_dpy'; }
95    inline bool isAlive() const { return isValid(); }
96
97    char const * getVendorString() const { return mVendorString.string(); }
98    char const * getVersionString() const { return mVersionString.string(); }
99    char const * getClientApiString() const { return mClientApiString.string(); }
100    char const * getExtensionString() const { return mExtensionString.string(); }
101
102    bool haveExtension(const char* name, size_t nameLen = 0) const;
103
104    inline uint32_t getRefsCount() const { return refs; }
105
106    struct strings_t {
107        char const * vendor;
108        char const * version;
109        char const * clientApi;
110        char const * extensions;
111    };
112
113    struct DisplayImpl {
114        DisplayImpl() : dpy(EGL_NO_DISPLAY), state(NOT_INITIALIZED) { }
115        EGLDisplay  dpy;
116        EGLint      state;
117        strings_t   queryString;
118    };
119
120private:
121    uint32_t        magic;
122
123public:
124    DisplayImpl     disp;
125    bool    finishOnSwap;       // property: debug.egl.finish
126    bool    traceGpuCompletion; // property: debug.egl.traceGpuCompletion
127
128private:
129    friend class egl_display_ptr;
130    bool enter() { return mHibernation.incWakeCount(HibernationMachine::WEAK); }
131    void leave() { return mHibernation.decWakeCount(HibernationMachine::WEAK); }
132
133            uint32_t                    refs;
134            bool                        eglIsInitialized;
135    mutable Mutex                       lock, refLock;
136    mutable Condition                   refCond;
137            SortedVector<egl_object_t*> objects;
138            String8 mVendorString;
139            String8 mVersionString;
140            String8 mClientApiString;
141            String8 mExtensionString;
142
143    // HibernationMachine uses its own internal mutex to protect its own data.
144    // The owning egl_display_t's lock may be but is not required to be held
145    // when calling HibernationMachine methods. As a result, nothing in this
146    // class may call back up to egl_display_t directly or indirectly.
147    class HibernationMachine {
148    public:
149        // STRONG refs cancel (inc) or initiate (dec) a hibernation attempt
150        // the next time the wakecount reaches zero. WEAK refs don't affect
151        // whether a hibernation attempt will be made. Use STRONG refs only
152        // for infrequent/heavy changes that are likely to indicate the
153        // EGLDisplay is entering or leaving a long-term idle state.
154        enum WakeRefStrength {
155            WEAK   = 0,
156            STRONG = 1,
157        };
158
159        HibernationMachine(): mWakeCount(0), mHibernating(false),
160                mAttemptHibernation(false), mDpyValid(false),
161#if BOARD_ALLOW_EGL_HIBERNATION
162                mAllowHibernation(true)
163#else
164                mAllowHibernation(false)
165#endif
166        {}
167        ~HibernationMachine() {}
168
169        bool incWakeCount(WakeRefStrength strenth);
170        void decWakeCount(WakeRefStrength strenth);
171
172        void setDisplayValid(bool valid);
173
174    private:
175        Mutex      mLock;
176        int32_t    mWakeCount;
177        bool       mHibernating;
178        bool       mAttemptHibernation;
179        bool       mDpyValid;
180        const bool mAllowHibernation;
181    };
182    HibernationMachine mHibernation;
183};
184
185// ----------------------------------------------------------------------------
186
187// An egl_display_ptr is a kind of smart pointer for egl_display_t objects.
188// It doesn't refcount the egl_display_t, but does ensure that the underlying
189// EGL implementation is "awake" (not hibernating) and ready for use as long
190// as the egl_display_ptr exists.
191class egl_display_ptr {
192public:
193    explicit egl_display_ptr(egl_display_t* dpy): mDpy(dpy) {
194        if (mDpy) {
195            if (CC_UNLIKELY(!mDpy->enter())) {
196                mDpy = NULL;
197            }
198        }
199    }
200
201    // We only really need a C++11 move constructor, not a copy constructor.
202    // A move constructor would save an enter()/leave() pair on every EGL API
203    // call. But enabling -std=c++0x causes lots of errors elsewhere, so I
204    // can't use a move constructor until those are cleaned up.
205    //
206    // egl_display_ptr(egl_display_ptr&& other) {
207    //     mDpy = other.mDpy;
208    //     other.mDpy = NULL;
209    // }
210    //
211    egl_display_ptr(const egl_display_ptr& other): mDpy(other.mDpy) {
212        if (mDpy) {
213            mDpy->enter();
214        }
215    }
216
217    ~egl_display_ptr() {
218        if (mDpy) {
219            mDpy->leave();
220        }
221    }
222
223    const egl_display_t* operator->() const { return mDpy; }
224          egl_display_t* operator->()       { return mDpy; }
225
226    const egl_display_t* get() const { return mDpy; }
227          egl_display_t* get()       { return mDpy; }
228
229    operator bool() const { return mDpy != NULL; }
230
231private:
232    egl_display_t* mDpy;
233
234    // non-assignable
235    egl_display_ptr& operator=(const egl_display_ptr&);
236};
237
238// ----------------------------------------------------------------------------
239
240inline egl_display_ptr get_display(EGLDisplay dpy) {
241    return egl_display_ptr(egl_display_t::get(dpy));
242}
243
244// Does not ensure EGL is unhibernated. Use with caution: calls into the
245// underlying EGL implementation are not safe.
246inline egl_display_t* get_display_nowake(EGLDisplay dpy) {
247    return egl_display_t::get(dpy);
248}
249
250// ----------------------------------------------------------------------------
251
252egl_display_ptr validate_display(EGLDisplay dpy);
253egl_display_ptr validate_display_connection(EGLDisplay dpy,
254        egl_connection_t*& cnx);
255EGLBoolean validate_display_context(EGLDisplay dpy, EGLContext ctx);
256EGLBoolean validate_display_surface(EGLDisplay dpy, EGLSurface surface);
257
258// ----------------------------------------------------------------------------
259}; // namespace android
260// ----------------------------------------------------------------------------
261
262#endif // ANDROID_EGL_DISPLAY_H
263