1 /*
2 * Copyright (C) 2009 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 #include <stdint.h>
18 #include <errno.h>
19 #include <sys/types.h>
20
21 #include <utils/threads.h>
22 #include <utils/Timers.h>
23 #include <utils/Log.h>
24 #include <binder/IPCThreadState.h>
25
26 #include "MessageQueue.h"
27
28 namespace android {
29
30 // ---------------------------------------------------------------------------
31
insert(const sp<MessageBase> & node)32 void MessageList::insert(const sp<MessageBase>& node)
33 {
34 LIST::iterator cur(mList.begin());
35 LIST::iterator end(mList.end());
36 while (cur != end) {
37 if (*node < **cur) {
38 mList.insert(cur, node);
39 return;
40 }
41 ++cur;
42 }
43 mList.insert(++end, node);
44 }
45
remove(MessageList::LIST::iterator pos)46 void MessageList::remove(MessageList::LIST::iterator pos)
47 {
48 mList.erase(pos);
49 }
50
51 // ---------------------------------------------------------------------------
52
MessageQueue()53 MessageQueue::MessageQueue()
54 : mInvalidate(false)
55 {
56 mInvalidateMessage = new MessageBase(INVALIDATE);
57 }
58
~MessageQueue()59 MessageQueue::~MessageQueue()
60 {
61 }
62
waitMessage(nsecs_t timeout)63 sp<MessageBase> MessageQueue::waitMessage(nsecs_t timeout)
64 {
65 sp<MessageBase> result;
66
67 bool again;
68 do {
69 const nsecs_t timeoutTime = systemTime() + timeout;
70 while (true) {
71 Mutex::Autolock _l(mLock);
72 nsecs_t now = systemTime();
73 nsecs_t nextEventTime = -1;
74
75 LIST::iterator cur(mMessages.begin());
76 if (cur != mMessages.end()) {
77 result = *cur;
78 }
79
80 if (result != 0) {
81 if (result->when <= now) {
82 // there is a message to deliver
83 mMessages.remove(cur);
84 break;
85 }
86 nextEventTime = result->when;
87 result = 0;
88 }
89
90 // see if we have an invalidate message
91 if (mInvalidate) {
92 mInvalidate = false;
93 mInvalidateMessage->when = now;
94 result = mInvalidateMessage;
95 break;
96 }
97
98 if (timeout >= 0) {
99 if (timeoutTime < now) {
100 // we timed-out, return a NULL message
101 result = 0;
102 break;
103 }
104 if (nextEventTime > 0) {
105 if (nextEventTime > timeoutTime) {
106 nextEventTime = timeoutTime;
107 }
108 } else {
109 nextEventTime = timeoutTime;
110 }
111 }
112
113 if (nextEventTime >= 0) {
114 //LOGD("nextEventTime = %lld ms", nextEventTime);
115 if (nextEventTime > 0) {
116 // we're about to wait, flush the binder command buffer
117 IPCThreadState::self()->flushCommands();
118 const nsecs_t reltime = nextEventTime - systemTime();
119 if (reltime > 0) {
120 mCondition.waitRelative(mLock, reltime);
121 }
122 }
123 } else {
124 //LOGD("going to wait");
125 // we're about to wait, flush the binder command buffer
126 IPCThreadState::self()->flushCommands();
127 mCondition.wait(mLock);
128 }
129 }
130 // here we're not holding the lock anymore
131
132 if (result == 0)
133 break;
134
135 again = result->handler();
136 if (again) {
137 // the message has been processed. release our reference to it
138 // without holding the lock.
139 result->notify();
140 result = 0;
141 }
142
143 } while (again);
144
145 return result;
146 }
147
postMessage(const sp<MessageBase> & message,nsecs_t relTime,uint32_t flags)148 status_t MessageQueue::postMessage(
149 const sp<MessageBase>& message, nsecs_t relTime, uint32_t flags)
150 {
151 return queueMessage(message, relTime, flags);
152 }
153
invalidate()154 status_t MessageQueue::invalidate() {
155 Mutex::Autolock _l(mLock);
156 mInvalidate = true;
157 mCondition.signal();
158 return NO_ERROR;
159 }
160
queueMessage(const sp<MessageBase> & message,nsecs_t relTime,uint32_t flags)161 status_t MessageQueue::queueMessage(
162 const sp<MessageBase>& message, nsecs_t relTime, uint32_t flags)
163 {
164 Mutex::Autolock _l(mLock);
165 message->when = systemTime() + relTime;
166 mMessages.insert(message);
167
168 //LOGD("MessageQueue::queueMessage time = %lld ms", message->when);
169 //dumpLocked(message);
170
171 mCondition.signal();
172 return NO_ERROR;
173 }
174
dump(const sp<MessageBase> & message)175 void MessageQueue::dump(const sp<MessageBase>& message)
176 {
177 Mutex::Autolock _l(mLock);
178 dumpLocked(message);
179 }
180
dumpLocked(const sp<MessageBase> & message)181 void MessageQueue::dumpLocked(const sp<MessageBase>& message)
182 {
183 LIST::const_iterator cur(mMessages.begin());
184 LIST::const_iterator end(mMessages.end());
185 int c = 0;
186 while (cur != end) {
187 const char tick = (*cur == message) ? '>' : ' ';
188 LOGD("%c %d: msg{.what=%08x, when=%lld}",
189 tick, c, (*cur)->what, (*cur)->when);
190 ++cur;
191 c++;
192 }
193 }
194
195 // ---------------------------------------------------------------------------
196
197 }; // namespace android
198