1/*
2 * Copyright (C) 2011 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
19#include <common_time/cc_helper.h>
20#include <common_time/ICommonClock.h>
21#include <utils/threads.h>
22
23namespace android {
24
25Mutex CCHelper::lock_;
26sp<ICommonClock> CCHelper::common_clock_;
27sp<ICommonClockListener> CCHelper::common_clock_listener_;
28uint32_t CCHelper::ref_count_ = 0;
29
30bool CCHelper::verifyClock_l() {
31    bool ret = false;
32
33    if (common_clock_ == NULL) {
34        common_clock_ = ICommonClock::getInstance();
35        if (common_clock_ == NULL)
36            goto bailout;
37    }
38
39    if (ref_count_ > 0) {
40        if (common_clock_listener_ == NULL) {
41            common_clock_listener_ = new CommonClockListener();
42            if (common_clock_listener_ == NULL)
43                goto bailout;
44
45            if (OK != common_clock_->registerListener(common_clock_listener_))
46                goto bailout;
47        }
48    }
49
50    ret = true;
51
52bailout:
53    if (!ret) {
54        common_clock_listener_ = NULL;
55        common_clock_ = NULL;
56    }
57    return ret;
58}
59
60CCHelper::CCHelper() {
61    Mutex::Autolock lock(&lock_);
62    ref_count_++;
63    verifyClock_l();
64}
65
66CCHelper::~CCHelper() {
67    Mutex::Autolock lock(&lock_);
68
69    assert(ref_count_ > 0);
70    ref_count_--;
71
72    // If we were the last CCHelper instance in the system, and we had
73    // previously register a listener, unregister it now so that the common time
74    // service has the chance to go into auto-disabled mode.
75    if (!ref_count_ &&
76       (common_clock_ != NULL) &&
77       (common_clock_listener_ != NULL)) {
78        common_clock_->unregisterListener(common_clock_listener_);
79        common_clock_listener_ = NULL;
80    }
81}
82
83void CCHelper::CommonClockListener::onTimelineChanged(uint64_t timelineID) {
84    // do nothing; listener is only really used as a token so the server can
85    // find out when clients die.
86}
87
88// Helper methods which attempts to make calls to the common time binder
89// service.  If the first attempt fails with DEAD_OBJECT, the helpers will
90// attempt to make a connection to the service again (assuming that the process
91// hosting the service had crashed and the client proxy we are holding is dead)
92// If the second attempt fails, or no connection can be made, the we let the
93// error propagate up the stack and let the caller deal with the situation as
94// best they can.
95#define CCHELPER_METHOD(decl, call)                 \
96    status_t CCHelper::decl {                       \
97        Mutex::Autolock lock(&lock_);               \
98                                                    \
99        if (!verifyClock_l())                       \
100            return DEAD_OBJECT;                     \
101                                                    \
102        status_t status = common_clock_->call;      \
103        if (DEAD_OBJECT == status) {                \
104            if (!verifyClock_l())                   \
105                return DEAD_OBJECT;                 \
106            status = common_clock_->call;           \
107        }                                           \
108                                                    \
109        return status;                              \
110    }
111
112#define VERIFY_CLOCK()
113
114CCHELPER_METHOD(isCommonTimeValid(bool* valid, uint32_t* timelineID),
115                isCommonTimeValid(valid, timelineID))
116CCHELPER_METHOD(commonTimeToLocalTime(int64_t commonTime, int64_t* localTime),
117                commonTimeToLocalTime(commonTime, localTime))
118CCHELPER_METHOD(localTimeToCommonTime(int64_t localTime, int64_t* commonTime),
119                localTimeToCommonTime(localTime, commonTime))
120CCHELPER_METHOD(getCommonTime(int64_t* commonTime),
121                getCommonTime(commonTime))
122CCHELPER_METHOD(getCommonFreq(uint64_t* freq),
123                getCommonFreq(freq))
124CCHELPER_METHOD(getLocalTime(int64_t* localTime),
125                getLocalTime(localTime))
126CCHELPER_METHOD(getLocalFreq(uint64_t* freq),
127                getLocalFreq(freq))
128
129}  // namespace android
130