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/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//#define LOG_NDEBUG 0
#define LOG_TAG "HTTPBase"
#include <utils/Log.h>
#include <datasource/HTTPBase.h>
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/ALooper.h>
#include <cutils/properties.h>
#include <cutils/qtaguid.h>
namespace android {
HTTPBase::HTTPBase()
: mNumBandwidthHistoryItems(0),
mTotalTransferTimeUs(0),
mTotalTransferBytes(0),
mMaxBandwidthHistoryItems(100),
mPrevBandwidthMeasureTimeUs(0),
mPrevEstimatedBandWidthKbps(0),
mBandWidthCollectFreqMs(5000) {
mName = String8("HTTPBase(<disconnected>)");
}
void HTTPBase::addBandwidthMeasurement(
size_t numBytes, int64_t delayUs) {
Mutex::Autolock autoLock(mLock);
BandwidthEntry entry;
entry.mDelayUs = delayUs;
entry.mNumBytes = numBytes;
mTotalTransferTimeUs += delayUs;
mTotalTransferBytes += numBytes;
mBandwidthHistory.push_back(entry);
if (++mNumBandwidthHistoryItems > mMaxBandwidthHistoryItems) {
BandwidthEntry *entry = &*mBandwidthHistory.begin();
mTotalTransferTimeUs -= entry->mDelayUs;
mTotalTransferBytes -= entry->mNumBytes;
mBandwidthHistory.erase(mBandwidthHistory.begin());
--mNumBandwidthHistoryItems;
int64_t timeNowUs = ALooper::GetNowUs();
if (timeNowUs - mPrevBandwidthMeasureTimeUs >=
mBandWidthCollectFreqMs * 1000LL) {
if (mPrevBandwidthMeasureTimeUs != 0) {
mPrevEstimatedBandWidthKbps =
(mTotalTransferBytes * 8E3 / mTotalTransferTimeUs);
}
mPrevBandwidthMeasureTimeUs = timeNowUs;
}
}
}
bool HTTPBase::estimateBandwidth(int32_t *bandwidth_bps) {
Mutex::Autolock autoLock(mLock);
// Do not do bandwidth estimation if we don't have enough samples, or
// total bytes download are too small (<64K).
// Bandwidth estimation from these samples can often shoot up and cause
// unwanted bw adaption behaviors.
if (mNumBandwidthHistoryItems < 2 || mTotalTransferBytes < 65536) {
return false;
}
*bandwidth_bps = ((double)mTotalTransferBytes * 8E6 / mTotalTransferTimeUs);
return true;
}
status_t HTTPBase::getEstimatedBandwidthKbps(int32_t *kbps) {
Mutex::Autolock autoLock(mLock);
*kbps = mPrevEstimatedBandWidthKbps;
return OK;
}
status_t HTTPBase::setBandwidthStatCollectFreq(int32_t freqMs) {
Mutex::Autolock autoLock(mLock);
if (freqMs < kMinBandwidthCollectFreqMs
|| freqMs > kMaxBandwidthCollectFreqMs) {
ALOGE("frequency (%d ms) is out of range [1000, 60000]", freqMs);
return BAD_VALUE;
}
ALOGI("frequency set to %d ms", freqMs);
mBandWidthCollectFreqMs = freqMs;
return OK;
}
void HTTPBase::setBandwidthHistorySize(size_t numHistoryItems) {
mMaxBandwidthHistoryItems = numHistoryItems;
}
} // namespace android
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