Provide bandwidth estimation support in NuHTTPDataSource (c62165b8) · Commits · e / os / android_frameworks_av

media/libstagefright/NuHTTPDataSource.cpp

+53 −0

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@
		#include "include/NuHTTPDataSource.h"

		#include <cutils/properties.h>
		#include <media/stagefright/foundation/ALooper.h>
		#include <media/stagefright/MediaDebug.h>
		#include <media/stagefright/MediaErrors.h>

		@@ -68,6 +69,9 @@ NuHTTPDataSource::NuHTTPDataSource()
		mOffset(0),
		mContentLength(0),
		mContentLengthValid(false),
		mNumBandwidthHistoryItems(0),
		mTotalTransferTimeUs(0),
		mTotalTransferBytes(0),
		mDecryptHandle(NULL),
		mDrmManagerClient(NULL) {
		}
		@@ -189,6 +193,20 @@ status_t NuHTTPDataSource::connect(
		return ERROR_IO;
		}

		{
		string value;
		if (mHTTP.find_header_value("Transfer-Encoding", &value)) {
		// We don't currently support any transfer encodings.

		mState = DISCONNECTED;
		mHTTP.disconnect();

		LOGE("We don't support '%s' transfer encoding.", value.c_str());

		return ERROR_UNSUPPORTED;
		}
		}

		applyTimeoutResponse();

		if (offset == 0) {
		@@ -254,6 +272,8 @@ ssize_t NuHTTPDataSource::readAt(off_t offset, void *data, size_t size) {

		size_t numBytesRead = 0;
		while (numBytesRead < size) {
		int64_t startTimeUs = ALooper::GetNowUs();

		ssize_t n =
		mHTTP.receive((uint8_t *)data + numBytesRead, size - numBytesRead);

		@@ -261,6 +281,9 @@ ssize_t NuHTTPDataSource::readAt(off_t offset, void *data, size_t size) {
		return n;
		}

		int64_t delayUs = ALooper::GetNowUs() - startTimeUs;
		addBandwidthMeasurement_l(n, delayUs);

		numBytesRead += (size_t)n;

		if (n == 0) {
		@@ -345,6 +368,36 @@ void NuHTTPDataSource::applyTimeoutResponse() {
		}
		}

		bool NuHTTPDataSource::estimateBandwidth(int32_t *bandwidth_bps) {
		Mutex::Autolock autoLock(mLock);

		if (mNumBandwidthHistoryItems < 10) {
		return false;
		}

		bandwidth_bps = ((double)mTotalTransferBytes 8E6 / mTotalTransferTimeUs);

		return true;
		}

		void NuHTTPDataSource::addBandwidthMeasurement_l(
		size_t numBytes, int64_t delayUs) {
		BandwidthEntry entry;
		entry.mDelayUs = delayUs;
		entry.mNumBytes = numBytes;
		mTotalTransferTimeUs += delayUs;
		mTotalTransferBytes += numBytes;

		mBandwidthHistory.push_back(entry);
		if (++mNumBandwidthHistoryItems > 100) {
		BandwidthEntry entry = &mBandwidthHistory.begin();
		mTotalTransferTimeUs -= entry->mDelayUs;
		mTotalTransferBytes -= entry->mNumBytes;
		mBandwidthHistory.erase(mBandwidthHistory.begin());
		--mNumBandwidthHistoryItems;
		}
		}

		DecryptHandle* NuHTTPDataSource::DrmInitialization(DrmManagerClient* client) {
		if (client == NULL) {
		return NULL;

media/libstagefright/include/NuHTTPDataSource.h

+16 −0

Original line number	Diff line number	Diff line
		@@ -3,6 +3,7 @@
		#define NU_HTTP_DATA_SOURCE_H_

		#include <media/stagefright/DataSource.h>
		#include <utils/List.h>
		#include <utils/String8.h>
		#include <utils/threads.h>

		@@ -26,6 +27,10 @@ struct NuHTTPDataSource : public DataSource {
		virtual status_t getSize(off_t *size);
		virtual uint32_t flags();

		// Returns true if bandwidth could successfully be estimated,
		// false otherwise.
		bool estimateBandwidth(int32_t *bandwidth_bps);

		virtual DecryptHandle* DrmInitialization(DrmManagerClient *client);
		virtual void getDrmInfo(DecryptHandle handle, DrmManagerClient client);

		@@ -39,6 +44,11 @@ private:
		CONNECTED
		};

		struct BandwidthEntry {
		int64_t mDelayUs;
		size_t mNumBytes;
		};

		Mutex mLock;

		State mState;
		@@ -54,6 +64,11 @@ private:
		off_t mContentLength;
		bool mContentLengthValid;

		List<BandwidthEntry> mBandwidthHistory;
		size_t mNumBandwidthHistoryItems;
		int64_t mTotalTransferTimeUs;
		size_t mTotalTransferBytes;

		DecryptHandle *mDecryptHandle;
		DrmManagerClient *mDrmManagerClient;

		@@ -66,6 +81,7 @@ private:
		off_t offset);

		void applyTimeoutResponse();
		void addBandwidthMeasurement_l(size_t numBytes, int64_t delayUs);

		static void MakeFullHeaders(
		const KeyedVector<String8, String8> *overrides,