tenfourfox/dom/media/StreamBuffer.cpp

118 lines
2.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "StreamBuffer.h"
#include "mozilla/Logging.h"
#include <algorithm>
namespace mozilla {
extern LazyLogModule gMediaStreamGraphLog;
#define STREAM_LOG(type, msg) MOZ_LOG(gMediaStreamGraphLog, type, msg)
#ifdef DEBUG
void
StreamBuffer::DumpTrackInfo() const
{
STREAM_LOG(LogLevel::Info, ("DumpTracks: mTracksKnownTime %lld", mTracksKnownTime));
for (uint32_t i = 0; i < mTracks.Length(); ++i) {
Track* track = mTracks[i];
if (track->IsEnded()) {
STREAM_LOG(LogLevel::Info, ("Track[%d] %d: ended", i, track->GetID()));
} else {
STREAM_LOG(LogLevel::Info, ("Track[%d] %d: %lld", i, track->GetID(),
track->GetEnd()));
}
}
}
#endif
StreamTime
StreamBuffer::GetEnd() const
{
StreamTime t = mTracksKnownTime;
for (uint32_t i = 0; i < mTracks.Length(); ++i) {
Track* track = mTracks[i];
if (!track->IsEnded()) {
t = std::min(t, track->GetEnd());
}
}
return t;
}
StreamTime
StreamBuffer::GetAllTracksEnd() const
{
if (mTracksKnownTime < STREAM_TIME_MAX) {
// A track might be added.
return STREAM_TIME_MAX;
}
StreamTime t = 0;
for (uint32_t i = 0; i < mTracks.Length(); ++i) {
Track* track = mTracks[i];
if (!track->IsEnded()) {
return STREAM_TIME_MAX;
}
t = std::max(t, track->GetEnd());
}
return t;
}
StreamBuffer::Track*
StreamBuffer::FindTrack(TrackID aID)
{
if (aID == TRACK_NONE || mTracks.IsEmpty()) {
return nullptr;
}
// The tracks are sorted by ID. We can use a binary search.
uint32_t left = 0, right = mTracks.Length() - 1;
while (left <= right) {
uint32_t middle = (left + right) / 2;
if (mTracks[middle]->GetID() == aID) {
return mTracks[middle];
}
if (mTracks[middle]->GetID() > aID) {
if (middle == 0) {
break;
}
right = middle - 1;
} else {
left = middle + 1;
}
}
return nullptr;
}
void
StreamBuffer::ForgetUpTo(StreamTime aTime)
{
// Only prune if there is a reasonable chunk (50ms @ 48kHz) to forget, so we
// don't spend too much time pruning segments.
const StreamTime minChunkSize = 2400;
if (aTime < mForgottenTime + minChunkSize) {
return;
}
mForgottenTime = aTime;
for (uint32_t i = 0; i < mTracks.Length(); ++i) {
Track* track = mTracks[i];
if (track->IsEnded() && track->GetEnd() <= aTime) {
mTracks.RemoveElementAt(i);
mTracksDirty = true;
--i;
continue;
}
StreamTime forgetTo = std::min(track->GetEnd() - 1, aTime);
track->ForgetUpTo(forgetTo);
}
}
} // namespace mozilla