1/*
2 * Copyright (C) 2013 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_TAG "MediaLog"
18//#define LOG_NDEBUG 0
19
20#include <sys/mman.h>
21#include <utils/Log.h>
22#include <binder/PermissionCache.h>
23#include <media/nbaio/NBLog.h>
24#include <private/android_filesystem_config.h>
25#include "MediaLogService.h"
26
27namespace android {
28
29// static const char kDeadlockedString[] = "MediaLogService may be deadlocked\n";
30MediaLogService::MediaLogService() :
31    BnMediaLogService(),
32    mMergerShared((NBLog::Shared*) malloc(NBLog::Timeline::sharedSize(kMergeBufferSize))),
33    mMerger(mMergerShared, kMergeBufferSize),
34    mMergeReader(mMergerShared, kMergeBufferSize, mMerger),
35    mMergeThread(new NBLog::MergeThread(mMerger))
36{
37    mMergeThread->run("MergeThread");
38}
39
40MediaLogService::~MediaLogService()
41{
42    mMergeThread->requestExit();
43    mMergeThread->setTimeoutUs(0);
44    mMergeThread->join();
45    free(mMergerShared);
46}
47
48void MediaLogService::registerWriter(const sp<IMemory>& shared, size_t size, const char *name)
49{
50    if (IPCThreadState::self()->getCallingUid() != AID_AUDIOSERVER || shared == 0 ||
51            size < kMinSize || size > kMaxSize || name == NULL ||
52            shared->size() < NBLog::Timeline::sharedSize(size)) {
53        return;
54    }
55    sp<NBLog::Reader> reader(new NBLog::Reader(shared, size));
56    NBLog::NamedReader namedReader(reader, name);
57    Mutex::Autolock _l(mLock);
58    mNamedReaders.add(namedReader);
59    mMerger.addReader(namedReader);
60}
61
62void MediaLogService::unregisterWriter(const sp<IMemory>& shared)
63{
64    if (IPCThreadState::self()->getCallingUid() != AID_AUDIOSERVER || shared == 0) {
65        return;
66    }
67    Mutex::Autolock _l(mLock);
68    for (size_t i = 0; i < mNamedReaders.size(); ) {
69        if (mNamedReaders[i].reader()->isIMemory(shared)) {
70            mNamedReaders.removeAt(i);
71        } else {
72            i++;
73        }
74    }
75}
76
77bool MediaLogService::dumpTryLock(Mutex& mutex)
78{
79    bool locked = false;
80    for (int i = 0; i < kDumpLockRetries; ++i) {
81        if (mutex.tryLock() == NO_ERROR) {
82            locked = true;
83            break;
84        }
85        usleep(kDumpLockSleepUs);
86    }
87    return locked;
88}
89
90status_t MediaLogService::dump(int fd, const Vector<String16>& args __unused)
91{
92    // FIXME merge with similar but not identical code at services/audioflinger/ServiceUtilities.cpp
93    static const String16 sDump("android.permission.DUMP");
94    if (!(IPCThreadState::self()->getCallingUid() == AID_AUDIOSERVER ||
95            PermissionCache::checkCallingPermission(sDump))) {
96        dprintf(fd, "Permission Denial: can't dump media.log from pid=%d, uid=%d\n",
97                IPCThreadState::self()->getCallingPid(),
98                IPCThreadState::self()->getCallingUid());
99        return NO_ERROR;
100    }
101
102#if 0
103    Vector<NBLog::NamedReader> namedReaders;
104    {
105        bool locked = dumpTryLock(mLock);
106
107        // failed to lock - MediaLogService is probably deadlocked
108        if (!locked) {
109            String8 result(kDeadlockedString);
110            if (fd >= 0) {
111                write(fd, result.string(), result.size());
112            } else {
113                ALOGW("%s:", result.string());
114            }
115            return NO_ERROR;
116        }
117            // namedReaders = mNamedReaders;
118            // for (size_t i = 0; i < namedReaders.size(); i++) {
119            //     const NBLog::NamedReader& namedReader = namedReaders[i];
120            //     if (fd >= 0) {
121            //         dprintf(fd, "\n%s:\n", namedReader.name());
122            //     } else {
123            //         ALOGI("%s:", namedReader.name());
124            //     }
125            //     namedReader.reader()->dump(fd, 0 /*indent*/);
126            // }
127
128        mLock.unlock();
129    }
130#endif
131    // FIXME request merge to make sure log is up to date
132    mMergeReader.dump(fd);
133    return NO_ERROR;
134}
135
136status_t MediaLogService::onTransact(uint32_t code, const Parcel& data, Parcel* reply,
137        uint32_t flags)
138{
139    return BnMediaLogService::onTransact(code, data, reply, flags);
140}
141
142void MediaLogService::requestMergeWakeup() {
143    mMergeThread->wakeup();
144}
145
146}   // namespace android
147