1 /*
2  * Copyright (C) 2005 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_PROCESS_STATE_H
18 #define ANDROID_PROCESS_STATE_H
19 
20 #include <binder/IBinder.h>
21 #include <utils/KeyedVector.h>
22 #include <utils/String8.h>
23 #include <utils/String16.h>
24 
25 #include <utils/threads.h>
26 
27 #include <pthread.h>
28 
29 // ---------------------------------------------------------------------------
30 namespace android {
31 
32 class IPCThreadState;
33 
34 class ProcessState : public virtual RefBase
35 {
36 public:
37     static  sp<ProcessState>    self();
38     static  sp<ProcessState>    selfOrNull();
39 
40     /* initWithDriver() can be used to configure libbinder to use
41      * a different binder driver dev node. It must be called *before*
42      * any call to ProcessState::self(). The default is /dev/vndbinder
43      * for processes built with the VNDK and /dev/binder for those
44      * which are not.
45      *
46      * If this is called with nullptr, the behavior is the same as selfOrNull.
47      */
48     static  sp<ProcessState>    initWithDriver(const char *driver);
49 
50             sp<IBinder>         getContextObject(const sp<IBinder>& caller);
51 
52             void                startThreadPool();
53 
54     typedef bool (*context_check_func)(const String16& name,
55                                        const sp<IBinder>& caller,
56                                        void* userData);
57 
58             bool                becomeContextManager(
59                                     context_check_func checkFunc,
60                                     void* userData);
61 
62             sp<IBinder>         getStrongProxyForHandle(int32_t handle);
63             void                expungeHandle(int32_t handle, IBinder* binder);
64 
65             void                spawnPooledThread(bool isMain);
66 
67             status_t            setThreadPoolMaxThreadCount(size_t maxThreads);
68             void                giveThreadPoolName();
69 
70             String8             getDriverName();
71 
72             ssize_t             getKernelReferences(size_t count, uintptr_t* buf);
73 
74                                 // Only usable by the context manager.
75                                 // This refcount includes:
76                                 // 1. Strong references to the node by this and other processes
77                                 // 2. Temporary strong references held by the kernel during a
78                                 //    transaction on the node.
79                                 // It does NOT include local strong references to the node
80             ssize_t             getStrongRefCountForNodeByHandle(int32_t handle);
81 
82             enum class CallRestriction {
83                 // all calls okay
84                 NONE,
85                 // log when calls are blocking
86                 ERROR_IF_NOT_ONEWAY,
87                 // abort process on blocking calls
88                 FATAL_IF_NOT_ONEWAY,
89             };
90             // Sets calling restrictions for all transactions in this process. This must be called
91             // before any threads are spawned.
92             void setCallRestriction(CallRestriction restriction);
93 
94 private:
95     static  sp<ProcessState>    init(const char *defaultDriver, bool requireDefault);
96 
97     friend class IPCThreadState;
98 
99             explicit            ProcessState(const char* driver);
100                                 ~ProcessState();
101 
102                                 ProcessState(const ProcessState& o);
103             ProcessState&       operator=(const ProcessState& o);
104             String8             makeBinderThreadName();
105 
106             struct handle_entry {
107                 IBinder* binder;
108                 RefBase::weakref_type* refs;
109             };
110 
111             handle_entry*       lookupHandleLocked(int32_t handle);
112 
113             String8             mDriverName;
114             int                 mDriverFD;
115             void*               mVMStart;
116 
117             // Protects thread count variable below.
118             pthread_mutex_t     mThreadCountLock;
119             pthread_cond_t      mThreadCountDecrement;
120             // Number of binder threads current executing a command.
121             size_t              mExecutingThreadsCount;
122             // Maximum number for binder threads allowed for this process.
123             size_t              mMaxThreads;
124             // Time when thread pool was emptied
125             int64_t             mStarvationStartTimeMs;
126 
127     mutable Mutex               mLock;  // protects everything below.
128 
129             Vector<handle_entry>mHandleToObject;
130 
131             context_check_func  mBinderContextCheckFunc;
132             void*               mBinderContextUserData;
133 
134             String8             mRootDir;
135             bool                mThreadPoolStarted;
136     volatile int32_t            mThreadPoolSeq;
137 
138             CallRestriction     mCallRestriction;
139 };
140 
141 } // namespace android
142 
143 // ---------------------------------------------------------------------------
144 
145 #endif // ANDROID_PROCESS_STATE_H
146