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#include <utils/String8.h>
21
22#include "ALooperRoster.h"
23
24#include "ADebug.h"
25#include "AHandler.h"
26#include "AMessage.h"
27
28namespace android {
29
30static bool verboseStats = false;
31
32ALooperRoster::ALooperRoster()
33    : mNextHandlerID(1) {
34}
35
36ALooper::handler_id ALooperRoster::registerHandler(
37        const sp<ALooper> &looper, const sp<AHandler> &handler) {
38    Mutex::Autolock autoLock(mLock);
39
40    if (handler->id() != 0) {
41        CHECK(!"A handler must only be registered once.");
42        return INVALID_OPERATION;
43    }
44
45    HandlerInfo info;
46    info.mLooper = looper;
47    info.mHandler = handler;
48    ALooper::handler_id handlerID = mNextHandlerID++;
49    mHandlers.add(handlerID, info);
50
51    handler->setID(handlerID, looper);
52
53    return handlerID;
54}
55
56void ALooperRoster::unregisterHandler(ALooper::handler_id handlerID) {
57    Mutex::Autolock autoLock(mLock);
58
59    ssize_t index = mHandlers.indexOfKey(handlerID);
60
61    if (index < 0) {
62        return;
63    }
64
65    const HandlerInfo &info = mHandlers.valueAt(index);
66
67    sp<AHandler> handler = info.mHandler.promote();
68
69    if (handler != NULL) {
70        handler->setID(0, NULL);
71    }
72
73    mHandlers.removeItemsAt(index);
74}
75
76void ALooperRoster::unregisterStaleHandlers() {
77
78    Vector<sp<ALooper> > activeLoopers;
79    {
80        Mutex::Autolock autoLock(mLock);
81
82        for (size_t i = mHandlers.size(); i > 0;) {
83            i--;
84            const HandlerInfo &info = mHandlers.valueAt(i);
85
86            sp<ALooper> looper = info.mLooper.promote();
87            if (looper == NULL) {
88                ALOGV("Unregistering stale handler %d", mHandlers.keyAt(i));
89                mHandlers.removeItemsAt(i);
90            } else {
91                // At this point 'looper' might be the only sp<> keeping
92                // the object alive. To prevent it from going out of scope
93                // and having ~ALooper call this method again recursively
94                // and then deadlocking because of the Autolock above, add
95                // it to a Vector which will go out of scope after the lock
96                // has been released.
97                activeLoopers.add(looper);
98            }
99        }
100    }
101}
102
103static void makeFourCC(uint32_t fourcc, char *s, size_t bufsz) {
104    s[0] = (fourcc >> 24) & 0xff;
105    if (s[0]) {
106        s[1] = (fourcc >> 16) & 0xff;
107        s[2] = (fourcc >> 8) & 0xff;
108        s[3] = fourcc & 0xff;
109        s[4] = 0;
110    } else {
111        snprintf(s, bufsz, "%u", fourcc);
112    }
113}
114
115void ALooperRoster::dump(int fd, const Vector<String16>& args) {
116    bool clear = false;
117    bool oldVerbose = verboseStats;
118    for (size_t i = 0; i < args.size(); i++) {
119        if (args[i] == String16("-c")) {
120            clear = true;
121        } else if (args[i] == String16("-von")) {
122            verboseStats = true;
123        } else if (args[i] == String16("-voff")) {
124            verboseStats = false;
125        }
126    }
127    String8 s;
128    if (verboseStats && !oldVerbose) {
129        s.append("(verbose stats collection enabled, stats will be cleared)\n");
130    }
131
132    Mutex::Autolock autoLock(mLock);
133    size_t n = mHandlers.size();
134    s.appendFormat(" %zu registered handlers:\n", n);
135
136    for (size_t i = 0; i < n; i++) {
137        s.appendFormat("  %d: ", mHandlers.keyAt(i));
138        HandlerInfo &info = mHandlers.editValueAt(i);
139        sp<ALooper> looper = info.mLooper.promote();
140        if (looper != NULL) {
141            s.append(looper->getName());
142            sp<AHandler> handler = info.mHandler.promote();
143            if (handler != NULL) {
144                handler->mVerboseStats = verboseStats;
145                s.appendFormat(": %u messages processed", handler->mMessageCounter);
146                if (verboseStats) {
147                    for (size_t j = 0; j < handler->mMessages.size(); j++) {
148                        char fourcc[15];
149                        makeFourCC(handler->mMessages.keyAt(j), fourcc, sizeof(fourcc));
150                        s.appendFormat("\n    %s: %u",
151                                fourcc,
152                                handler->mMessages.valueAt(j));
153                    }
154                } else {
155                    handler->mMessages.clear();
156                }
157                if (clear || (verboseStats && !oldVerbose)) {
158                    handler->mMessageCounter = 0;
159                    handler->mMessages.clear();
160                }
161            } else {
162                s.append(": <stale handler>");
163            }
164        } else {
165            s.append("<stale>");
166        }
167        s.append("\n");
168    }
169    write(fd, s.string(), s.size());
170}
171
172}  // namespace android
173