Merge "Refetch playlists according to the HLS specs, varying delay if playlists unchanged" (698a5e08) · Commits · e / os / android_frameworks_base

media/libstagefright/httplive/LiveSession.cpp

+111 −12

Original line number	Diff line number	Diff line
		@@ -36,11 +36,10 @@

		#include <ctype.h>
		#include <openssl/aes.h>
		#include <openssl/md5.h>

		namespace android {

		const int64_t LiveSession::kMaxPlaylistAgeUs = 15000000ll;

		LiveSession::LiveSession(uint32_t flags, bool uidValid, uid_t uid)
		: mFlags(flags),
		mUIDValid(uidValid),
		@@ -59,7 +58,8 @@ LiveSession::LiveSession(uint32_t flags, bool uidValid, uid_t uid)
		mDurationUs(-1),
		mSeekDone(false),
		mDisconnectPending(false),
		mMonitorQueueGeneration(0) {
		mMonitorQueueGeneration(0),
		mRefreshState(INITIAL_MINIMUM_RELOAD_DELAY) {
		if (mUIDValid) {
		mHTTPDataSource->setUID(mUID);
		}
		@@ -175,7 +175,8 @@ void LiveSession::onConnect(const sp<AMessage> &msg) {

		mMasterURL = url;

		sp<M3UParser> playlist = fetchPlaylist(url.c_str());
		bool dummy;
		sp<M3UParser> playlist = fetchPlaylist(url.c_str(), &dummy);

		if (playlist == NULL) {
		LOGE("unable to fetch master playlist '%s'.", url.c_str());
		@@ -289,7 +290,9 @@ status_t LiveSession::fetchFile(const char url, sp<ABuffer> out) {
		return OK;
		}

		sp<M3UParser> LiveSession::fetchPlaylist(const char *url) {
		sp<M3UParser> LiveSession::fetchPlaylist(const char url, bool unchanged) {
		*unchanged = false;

		sp<ABuffer> buffer;
		status_t err = fetchFile(url, &buffer);

		@@ -297,6 +300,38 @@ sp<M3UParser> LiveSession::fetchPlaylist(const char *url) {
		return NULL;
		}

		// MD5 functionality is not available on the simulator, treat all
		// playlists as changed.

		#if defined(HAVE_ANDROID_OS)
		uint8_t hash[16];

		MD5_CTX m;
		MD5_Init(&m);
		MD5_Update(&m, buffer->data(), buffer->size());

		MD5_Final(hash, &m);

		if (mPlaylist != NULL && !memcmp(hash, mPlaylistHash, 16)) {
		// playlist unchanged

		if (mRefreshState != THIRD_UNCHANGED_RELOAD_ATTEMPT) {
		mRefreshState = (RefreshState)(mRefreshState + 1);
		}

		*unchanged = true;

		LOGV("Playlist unchanged, refresh state is now %d",
		(int)mRefreshState);

		return NULL;
		}

		memcpy(mPlaylistHash, hash, sizeof(hash));

		mRefreshState = INITIAL_MINIMUM_RELOAD_DELAY;
		#endif

		sp<M3UParser> playlist =
		new M3UParser(url, buffer->data(), buffer->size());

		@@ -384,6 +419,63 @@ size_t LiveSession::getBandwidthIndex() {
		return index;
		}

		bool LiveSession::timeToRefreshPlaylist(int64_t nowUs) const {
		if (mPlaylist == NULL) {
		CHECK_EQ((int)mRefreshState, (int)INITIAL_MINIMUM_RELOAD_DELAY);
		return true;
		}

		int32_t targetDurationSecs;
		CHECK(mPlaylist->meta()->findInt32("target-duration", &targetDurationSecs));

		int64_t targetDurationUs = targetDurationSecs * 1000000ll;

		int64_t minPlaylistAgeUs;

		switch (mRefreshState) {
		case INITIAL_MINIMUM_RELOAD_DELAY:
		{
		size_t n = mPlaylist->size();
		if (n > 0) {
		sp<AMessage> itemMeta;
		CHECK(mPlaylist->itemAt(n - 1, NULL /* uri */, &itemMeta));

		int64_t itemDurationUs;
		CHECK(itemMeta->findInt64("durationUs", &itemDurationUs));

		minPlaylistAgeUs = itemDurationUs;
		break;
		}

		// fall through
		}

		case FIRST_UNCHANGED_RELOAD_ATTEMPT:
		{
		minPlaylistAgeUs = targetDurationUs / 2;
		break;
		}

		case SECOND_UNCHANGED_RELOAD_ATTEMPT:
		{
		minPlaylistAgeUs = (targetDurationUs * 3) / 2;
		break;
		}

		case THIRD_UNCHANGED_RELOAD_ATTEMPT:
		{
		minPlaylistAgeUs = targetDurationUs * 3;
		break;
		}

		default:
		TRESPASS();
		break;
		}

		return mLastPlaylistFetchTimeUs + minPlaylistAgeUs <= nowUs;
		}

		void LiveSession::onDownloadNext() {
		size_t bandwidthIndex = getBandwidthIndex();

		@@ -392,8 +484,7 @@ rinse_repeat:

		if (mLastPlaylistFetchTimeUs < 0
		\|\| (ssize_t)bandwidthIndex != mPrevBandwidthIndex
		\|\| (!mPlaylist->isComplete()
		&& mLastPlaylistFetchTimeUs + kMaxPlaylistAgeUs <= nowUs)) {
		\|\| (!mPlaylist->isComplete() && timeToRefreshPlaylist(nowUs))) {
		AString url;
		if (mBandwidthItems.size() > 0) {
		url = mBandwidthItems.editItemAt(bandwidthIndex).mURI;
		@@ -403,12 +494,20 @@ rinse_repeat:

		bool firstTime = (mPlaylist == NULL);

		mPlaylist = fetchPlaylist(url.c_str());
		if (mPlaylist == NULL) {
		bool unchanged;
		sp<M3UParser> playlist = fetchPlaylist(url.c_str(), &unchanged);
		if (playlist == NULL) {
		if (unchanged) {
		// We succeeded in fetching the playlist, but it was
		// unchanged from the last time we tried.
		} else {
		LOGE("failed to load playlist at url '%s'", url.c_str());
		mDataSource->queueEOS(ERROR_IO);
		return;
		}
		} else {
		mPlaylist = playlist;
		}

		if (firstTime) {
		Mutex::Autolock autoLock(mLock);

media/libstagefright/include/LiveSession.h

+13 −3

Original line number	Diff line number	Diff line
		@@ -62,8 +62,6 @@ private:
		kMaxNumRetries = 5,
		};

		static const int64_t kMaxPlaylistAgeUs;

		enum {
		kWhatConnect = 'conn',
		kWhatDisconnect = 'disc',
		@@ -106,6 +104,16 @@ private:

		int32_t mMonitorQueueGeneration;

		enum RefreshState {
		INITIAL_MINIMUM_RELOAD_DELAY,
		FIRST_UNCHANGED_RELOAD_ATTEMPT,
		SECOND_UNCHANGED_RELOAD_ATTEMPT,
		THIRD_UNCHANGED_RELOAD_ATTEMPT
		};
		RefreshState mRefreshState;

		uint8_t mPlaylistHash[16];

		void onConnect(const sp<AMessage> &msg);
		void onDisconnect();
		void onDownloadNext();
		@@ -113,7 +121,7 @@ private:
		void onSeek(const sp<AMessage> &msg);

		status_t fetchFile(const char url, sp<ABuffer> out);
		sp<M3UParser> fetchPlaylist(const char *url);
		sp<M3UParser> fetchPlaylist(const char url, bool unchanged);
		size_t getBandwidthIndex();

		status_t decryptBuffer(
		@@ -121,6 +129,8 @@ private:

		void postMonitorQueue(int64_t delayUs = 0);

		bool timeToRefreshPlaylist(int64_t nowUs) const;

		static int SortByBandwidth(const BandwidthItem , const BandwidthItem );

		DISALLOW_EVIL_CONSTRUCTORS(LiveSession);