ALooperRoster.cpp revision 0df36ec3303c2c6bf9b42c07945ac8bd234153f3 
1/*
2 * Copyright (C) 2010 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//#define LOG_NDEBUG 0
18#define LOG_TAG "ALooperRoster"
19#include <utils/Log.h>
20
21#include "ALooperRoster.h"
22
23#include "ADebug.h"
24#include "AHandler.h"
25#include "AMessage.h"
26
27namespace android {
28
29ALooperRoster::ALooperRoster()
30    : mNextHandlerID(1),
31      mNextReplyID(1) {
32}
33
34ALooper::handler_id ALooperRoster::registerHandler(
35        const sp<ALooper> looper, const sp<AHandler> &handler) {
36    Mutex::Autolock autoLock(mLock);
37
38    if (handler->id() != 0) {
39        CHECK(!"A handler must only be registered once.");
40        return INVALID_OPERATION;
41    }
42
43    HandlerInfo info;
44    info.mLooper = looper;
45    info.mHandler = handler;
46    ALooper::handler_id handlerID = mNextHandlerID++;
47    mHandlers.add(handlerID, info);
48
49    handler->setID(handlerID);
50
51    return handlerID;
52}
53
54void ALooperRoster::unregisterHandler(ALooper::handler_id handlerID) {
55    Mutex::Autolock autoLock(mLock);
56
57    ssize_t index = mHandlers.indexOfKey(handlerID);
58
59    if (index < 0) {
60        return;
61    }
62
63    const HandlerInfo &info = mHandlers.valueAt(index);
64
65    sp<AHandler> handler = info.mHandler.promote();
66
67    if (handler != NULL) {
68        handler->setID(0);
69    }
70
71    mHandlers.removeItemsAt(index);
72}
73
74status_t ALooperRoster::postMessage(
75        const sp<AMessage> &msg, int64_t delayUs) {
76    Mutex::Autolock autoLock(mLock);
77    return postMessage_l(msg, delayUs);
78}
79
80status_t ALooperRoster::postMessage_l(
81        const sp<AMessage> &msg, int64_t delayUs) {
82    ssize_t index = mHandlers.indexOfKey(msg->target());
83
84    if (index < 0) {
85        ALOGW("failed to post message '%s'. Target handler not registered.",
86              msg->debugString().c_str());
87        return -ENOENT;
88    }
89
90    const HandlerInfo &info = mHandlers.valueAt(index);
91
92    sp<ALooper> looper = info.mLooper.promote();
93
94    if (looper == NULL) {
95        ALOGW("failed to post message. "
96             "Target handler %d still registered, but object gone.",
97             msg->target());
98
99        mHandlers.removeItemsAt(index);
100        return -ENOENT;
101    }
102
103    looper->post(msg, delayUs);
104
105    return OK;
106}
107
108void ALooperRoster::deliverMessage(const sp<AMessage> &msg) {
109    sp<AHandler> handler;
110
111    {
112        Mutex::Autolock autoLock(mLock);
113
114        ssize_t index = mHandlers.indexOfKey(msg->target());
115
116        if (index < 0) {
117            ALOGW("failed to deliver message. Target handler not registered.");
118            return;
119        }
120
121        const HandlerInfo &info = mHandlers.valueAt(index);
122        handler = info.mHandler.promote();
123
124        if (handler == NULL) {
125            ALOGW("failed to deliver message. "
126                 "Target handler %d registered, but object gone.",
127                 msg->target());
128
129            mHandlers.removeItemsAt(index);
130            return;
131        }
132    }
133
134    handler->onMessageReceived(msg);
135}
136
137sp<ALooper> ALooperRoster::findLooper(ALooper::handler_id handlerID) {
138    Mutex::Autolock autoLock(mLock);
139
140    ssize_t index = mHandlers.indexOfKey(handlerID);
141
142    if (index < 0) {
143        return NULL;
144    }
145
146    sp<ALooper> looper = mHandlers.valueAt(index).mLooper.promote();
147
148    if (looper == NULL) {
149        mHandlers.removeItemsAt(index);
150        return NULL;
151    }
152
153    return looper;
154}
155
156status_t ALooperRoster::postAndAwaitResponse(
157        const sp<AMessage> &msg, sp<AMessage> *response) {
158    Mutex::Autolock autoLock(mLock);
159
160    uint32_t replyID = mNextReplyID++;
161
162    msg->setInt32("replyID", replyID);
163
164    status_t err = postMessage_l(msg, 0 /* delayUs */);
165
166    if (err != OK) {
167        response->clear();
168        return err;
169    }
170
171    ssize_t index;
172    while ((index = mReplies.indexOfKey(replyID)) < 0) {
173        mRepliesCondition.wait(mLock);
174    }
175
176    *response = mReplies.valueAt(index);
177    mReplies.removeItemsAt(index);
178
179    return OK;
180}
181
182void ALooperRoster::postReply(uint32_t replyID, const sp<AMessage> &reply) {
183    Mutex::Autolock autoLock(mLock);
184
185    CHECK(mReplies.indexOfKey(replyID) < 0);
186    mReplies.add(replyID, reply);
187    mRepliesCondition.broadcast();
188}
189
190}  // namespace android
191