The Tor Browser: content/media/ogg/OggCodecState.cpp@97036ab72558 (annotated)

content/media/ogg/OggCodecState.cpp@97036ab72558 (annotated)

content/media/ogg/OggCodecState.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim:set ts=2 sw=2 sts=2 et cindent: */
 /* 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 <string.h>
 #include "mozilla/DebugOnly.h"
 #include "mozilla/Endian.h"
 #include <stdint.h>
 #include "nsDebug.h"
 #include "MediaDecoderReader.h"
 #include "OggCodecState.h"
 #include "OggDecoder.h"
 #include "nsISupportsImpl.h"
 #include "VideoUtils.h"
 #include <algorithm>
 // On Android JellyBean, the hardware.h header redefines version_major and
 // version_minor, which breaks our build.  See:
 // https://bugzilla.mozilla.org/show_bug.cgi?id=912702#c6
 #ifdef MOZ_WIDGET_GONK
 #ifdef version_major
 #undef version_major
 #endif
 #ifdef version_minor
 #undef version_minor
 #endif
 #endif
 namespace mozilla {
 #ifdef PR_LOGGING
 extern PRLogModuleInfo* gMediaDecoderLog;
 #define LOG(type, msg) PR_LOG(gMediaDecoderLog, type, msg)
 #else
 #define LOG(type, msg)
 #endif
 /** Decoder base class for Ogg-encapsulated streams. */
 OggCodecState*
 OggCodecState::Create(ogg_page* aPage)
 {
   NS_ASSERTION(ogg_page_bos(aPage), "Only call on BOS page!");
   nsAutoPtr<OggCodecState> codecState;
   if (aPage->body_len > 6 && memcmp(aPage->body+1, "theora", 6) == 0) {
     codecState = new TheoraState(aPage);
   } else if (aPage->body_len > 6 && memcmp(aPage->body+1, "vorbis", 6) == 0) {
     codecState = new VorbisState(aPage);
 #ifdef MOZ_OPUS
   } else if (aPage->body_len > 8 && memcmp(aPage->body, "OpusHead", 8) == 0) {
     codecState = new OpusState(aPage);
 #endif
   } else if (aPage->body_len > 8 && memcmp(aPage->body, "fishead\0", 8) == 0) {
     codecState = new SkeletonState(aPage);
   } else {
     codecState = new OggCodecState(aPage, false);
   }
   return codecState->OggCodecState::Init() ? codecState.forget() : nullptr;
 }
 OggCodecState::OggCodecState(ogg_page* aBosPage, bool aActive) :
   mPacketCount(0),
   mSerial(ogg_page_serialno(aBosPage)),
   mActive(aActive),
   mDoneReadingHeaders(!aActive)
 {
   MOZ_COUNT_CTOR(OggCodecState);
   memset(&mState, 0, sizeof(ogg_stream_state));
 }
 OggCodecState::~OggCodecState() {
   MOZ_COUNT_DTOR(OggCodecState);
   Reset();
 #ifdef DEBUG
   int ret =
 #endif
   ogg_stream_clear(&mState);
   NS_ASSERTION(ret == 0, "ogg_stream_clear failed");
 }
 nsresult OggCodecState::Reset() {
   if (ogg_stream_reset(&mState) != 0) {
     return NS_ERROR_FAILURE;
   }
   mPackets.Erase();
   ClearUnstamped();
   return NS_OK;
 }
 void OggCodecState::ClearUnstamped()
 {
   for (uint32_t i = 0; i < mUnstamped.Length(); ++i) {
     OggCodecState::ReleasePacket(mUnstamped[i]);
   }
   mUnstamped.Clear();
 }
 bool OggCodecState::Init() {
   int ret = ogg_stream_init(&mState, mSerial);
   return ret == 0;
 }
 bool OggCodecState::IsValidVorbisTagName(nsCString& aName)
 {
   // Tag names must consist of ASCII 0x20 through 0x7D,
   // excluding 0x3D '=' which is the separator.
   uint32_t length = aName.Length();
   const char* data = aName.Data();
   for (uint32_t i = 0; i < length; i++) {
     if (data[i] < 0x20 || data[i] > 0x7D || data[i] == '=') {
       return false;
     }
   }
   return true;
 }
 bool OggCodecState::AddVorbisComment(MetadataTags* aTags,
                                        const char* aComment,
                                        uint32_t aLength)
 {
   const char* div = (const char*)memchr(aComment, '=', aLength);
   if (!div) {
     LOG(PR_LOG_DEBUG, ("Skipping comment: no separator"));
     return false;
   }
   nsCString key = nsCString(aComment, div-aComment);
   if (!IsValidVorbisTagName(key)) {
     LOG(PR_LOG_DEBUG, ("Skipping comment: invalid tag name"));
     return false;
   }
   uint32_t valueLength = aLength - (div-aComment);
   nsCString value = nsCString(div + 1, valueLength);
   if (!IsUTF8(value)) {
     LOG(PR_LOG_DEBUG, ("Skipping comment: invalid UTF-8 in value"));
     return false;
   }
   aTags->Put(key, value);
   return true;
 }
 void VorbisState::RecordVorbisPacketSamples(ogg_packet* aPacket,
                                               long aSamples)
 {
 #ifdef VALIDATE_VORBIS_SAMPLE_CALCULATION
   mVorbisPacketSamples[aPacket] = aSamples;
 #endif
 }
 void VorbisState::ValidateVorbisPacketSamples(ogg_packet* aPacket,
                                                 long aSamples)
 {
 #ifdef VALIDATE_VORBIS_SAMPLE_CALCULATION
   NS_ASSERTION(mVorbisPacketSamples[aPacket] == aSamples,
     "Decoded samples for Vorbis packet don't match expected!");
   mVorbisPacketSamples.erase(aPacket);
 #endif
 }
 void VorbisState::AssertHasRecordedPacketSamples(ogg_packet* aPacket)
 {
 #ifdef VALIDATE_VORBIS_SAMPLE_CALCULATION
   NS_ASSERTION(mVorbisPacketSamples.count(aPacket) == 1,
     "Must have recorded packet samples");
 #endif
 }
 static ogg_packet* Clone(ogg_packet* aPacket) {
   ogg_packet* p = new ogg_packet();
   memcpy(p, aPacket, sizeof(ogg_packet));
   p->packet = new unsigned char[p->bytes];
   memcpy(p->packet, aPacket->packet, p->bytes);
   return p;
 }
 void OggCodecState::ReleasePacket(ogg_packet* aPacket) {
   if (aPacket)
     delete [] aPacket->packet;
   delete aPacket;
 }
 void OggPacketQueue::Append(ogg_packet* aPacket) {
   nsDeque::Push(aPacket);
 }
 ogg_packet* OggCodecState::PacketOut() {
   if (mPackets.IsEmpty()) {
     return nullptr;
   }
   return mPackets.PopFront();
 }
 nsresult OggCodecState::PageIn(ogg_page* aPage) {
   if (!mActive)
     return NS_OK;
   NS_ASSERTION(static_cast<uint32_t>(ogg_page_serialno(aPage)) == mSerial,
                "Page must be for this stream!");
   if (ogg_stream_pagein(&mState, aPage) == -1)
     return NS_ERROR_FAILURE;
   int r;
   do {
     ogg_packet packet;
     r = ogg_stream_packetout(&mState, &packet);
     if (r == 1) {
       mPackets.Append(Clone(&packet));
     }
   } while (r != 0);
   if (ogg_stream_check(&mState)) {
     NS_WARNING("Unrecoverable error in ogg_stream_packetout");
     return NS_ERROR_FAILURE;
   }
   return NS_OK;
 }
 nsresult OggCodecState::PacketOutUntilGranulepos(bool& aFoundGranulepos) {
   int r;
   aFoundGranulepos = false;
   // Extract packets from the sync state until either no more packets
   // come out, or we get a data packet with non -1 granulepos.
   do {
     ogg_packet packet;
     r = ogg_stream_packetout(&mState, &packet);
     if (r == 1) {
       ogg_packet* clone = Clone(&packet);
       if (IsHeader(&packet)) {
         // Header packets go straight into the packet queue.
         mPackets.Append(clone);
       } else {
         // We buffer data packets until we encounter a granulepos. We'll
         // then use the granulepos to figure out the granulepos of the
         // preceeding packets.
         mUnstamped.AppendElement(clone);
         aFoundGranulepos = packet.granulepos > 0;
       }
     }
   } while (r != 0 && !aFoundGranulepos);
   if (ogg_stream_check(&mState)) {
     NS_WARNING("Unrecoverable error in ogg_stream_packetout");
     return NS_ERROR_FAILURE;
   }
   return NS_OK;
 }
 TheoraState::TheoraState(ogg_page* aBosPage) :
   OggCodecState(aBosPage, true),
   mSetup(0),
   mCtx(0),
   mPixelAspectRatio(0)
 {
   MOZ_COUNT_CTOR(TheoraState);
   th_info_init(&mInfo);
   th_comment_init(&mComment);
 }
 TheoraState::~TheoraState() {
   MOZ_COUNT_DTOR(TheoraState);
   th_setup_free(mSetup);
   th_decode_free(mCtx);
   th_comment_clear(&mComment);
   th_info_clear(&mInfo);
 }
 bool TheoraState::Init() {
   if (!mActive)
     return false;
   int64_t n = mInfo.aspect_numerator;
   int64_t d = mInfo.aspect_denominator;
   mPixelAspectRatio = (n == 0 || d == 0) ?
 .0f : static_cast<float>(n) / static_cast<float>(d);
   // Ensure the frame and picture regions aren't larger than our prescribed
   // maximum, or zero sized.
   nsIntSize frame(mInfo.frame_width, mInfo.frame_height);
   nsIntRect picture(mInfo.pic_x, mInfo.pic_y, mInfo.pic_width, mInfo.pic_height);
   if (!IsValidVideoRegion(frame, picture, frame)) {
     return mActive = false;
   }
   mCtx = th_decode_alloc(&mInfo, mSetup);
   if (mCtx == nullptr) {
     return mActive = false;
   }
   return true;
 }
 bool
 TheoraState::DecodeHeader(ogg_packet* aPacket)
 {
   nsAutoRef<ogg_packet> autoRelease(aPacket);
   mPacketCount++;
   int ret = th_decode_headerin(&mInfo,
                                &mComment,
                                &mSetup,
                                aPacket);
   // We must determine when we've read the last header packet.
   // th_decode_headerin() does not tell us when it's read the last header, so
   // we must keep track of the headers externally.
   //
   // There are 3 header packets, the Identification, Comment, and Setup
   // headers, which must be in that order. If they're out of order, the file
   // is invalid. If we've successfully read a header, and it's the setup
   // header, then we're done reading headers. The first byte of each packet
   // determines it's type as follows:
   //    0x80 -> Identification header
   //    0x81 -> Comment header
   //    0x82 -> Setup header
   // See http://www.theora.org/doc/Theora.pdf Chapter 6, "Bitstream Headers",
   // for more details of the Ogg/Theora containment scheme.
   bool isSetupHeader = aPacket->bytes > 0 && aPacket->packet[0] == 0x82;
   if (ret < 0 || mPacketCount > 3) {
     // We've received an error, or the first three packets weren't valid
     // header packets. Assume bad input.
     // Our caller will deactivate the bitstream.
     return false;
   } else if (ret > 0 && isSetupHeader && mPacketCount == 3) {
     // Successfully read the three header packets.
     mDoneReadingHeaders = true;
   }
   return true;
 }
 int64_t
 TheoraState::Time(int64_t granulepos) {
   if (!mActive) {
     return -1;
   }
   return TheoraState::Time(&mInfo, granulepos);
 }
 bool
 TheoraState::IsHeader(ogg_packet* aPacket) {
   return th_packet_isheader(aPacket);
 }
 # define TH_VERSION_CHECK(_info,_maj,_min,_sub) \
  (((_info)->version_major>(_maj)||(_info)->version_major==(_maj))&& \
  (((_info)->version_minor>(_min)||(_info)->version_minor==(_min))&& \
  (_info)->version_subminor>=(_sub)))
 int64_t TheoraState::Time(th_info* aInfo, int64_t aGranulepos)
 {
   if (aGranulepos < 0 || aInfo->fps_numerator == 0) {
     return -1;
   }
   // Implementation of th_granule_frame inlined here to operate
   // on the th_info structure instead of the theora_state.
   int shift = aInfo->keyframe_granule_shift;
   ogg_int64_t iframe = aGranulepos >> shift;
   ogg_int64_t pframe = aGranulepos - (iframe << shift);
   int64_t frameno = iframe + pframe - TH_VERSION_CHECK(aInfo, 3, 2, 1);
   CheckedInt64 t = ((CheckedInt64(frameno) + 1) * USECS_PER_S) * aInfo->fps_denominator;
   if (!t.isValid())
     return -1;
   t /= aInfo->fps_numerator;
   return t.isValid() ? t.value() : -1;
 }
 int64_t TheoraState::StartTime(int64_t granulepos) {
   if (granulepos < 0 || !mActive || mInfo.fps_numerator == 0) {
     return -1;
   }
   CheckedInt64 t = (CheckedInt64(th_granule_frame(mCtx, granulepos)) * USECS_PER_S) * mInfo.fps_denominator;
   if (!t.isValid())
     return -1;
   return t.value() / mInfo.fps_numerator;
 }
 int64_t
 TheoraState::MaxKeyframeOffset()
 {
   // Determine the maximum time in microseconds by which a key frame could
   // offset for the theora bitstream. Theora granulepos encode time as:
   // ((key_frame_number << granule_shift) + frame_offset).
   // Therefore the maximum possible time by which any frame could be offset
   // from a keyframe is the duration of (1 << granule_shift) - 1) frames.
   int64_t frameDuration;
   // Max number of frames keyframe could possibly be offset.
   int64_t keyframeDiff = (1 << mInfo.keyframe_granule_shift) - 1;
   // Length of frame in usecs.
   frameDuration = (mInfo.fps_denominator * USECS_PER_S) / mInfo.fps_numerator;
   // Total time in usecs keyframe can be offset from any given frame.
   return frameDuration * keyframeDiff;
 }
 nsresult
 TheoraState::PageIn(ogg_page* aPage)
 {
   if (!mActive)
     return NS_OK;
   NS_ASSERTION(static_cast<uint32_t>(ogg_page_serialno(aPage)) == mSerial,
                "Page must be for this stream!");
   if (ogg_stream_pagein(&mState, aPage) == -1)
     return NS_ERROR_FAILURE;
   bool foundGp;
   nsresult res = PacketOutUntilGranulepos(foundGp);
   if (NS_FAILED(res))
     return res;
   if (foundGp && mDoneReadingHeaders) {
     // We've found a packet with a granulepos, and we've loaded our metadata
     // and initialized our decoder. Determine granulepos of buffered packets.
     ReconstructTheoraGranulepos();
     for (uint32_t i = 0; i < mUnstamped.Length(); ++i) {
       ogg_packet* packet = mUnstamped[i];
 #ifdef DEBUG
       NS_ASSERTION(!IsHeader(packet), "Don't try to recover header packet gp");
       NS_ASSERTION(packet->granulepos != -1, "Packet must have gp by now");
 #endif
       mPackets.Append(packet);
     }
     mUnstamped.Clear();
   }
   return NS_OK;
 }
 // Returns 1 if the Theora info struct is decoding a media of Theora
 // version (maj,min,sub) or later, otherwise returns 0.
 int
 TheoraVersion(th_info* info,
               unsigned char maj,
               unsigned char min,
               unsigned char sub)
 {
   ogg_uint32_t ver = (maj << 16) + (min << 8) + sub;
   ogg_uint32_t th_ver = (info->version_major << 16) +
                         (info->version_minor << 8) +
                         info->version_subminor;
   return (th_ver >= ver) ? 1 : 0;
 }
 void TheoraState::ReconstructTheoraGranulepos()
 {
   if (mUnstamped.Length() == 0) {
     return;
   }
   ogg_int64_t lastGranulepos = mUnstamped[mUnstamped.Length() - 1]->granulepos;
   NS_ASSERTION(lastGranulepos != -1, "Must know last granulepos");
   // Reconstruct the granulepos (and thus timestamps) of the decoded
   // frames. Granulepos are stored as ((keyframe<<shift)+offset). We
   // know the granulepos of the last frame in the list, so we can infer
   // the granulepos of the intermediate frames using their frame numbers.
   ogg_int64_t shift = mInfo.keyframe_granule_shift;
   ogg_int64_t version_3_2_1 = TheoraVersion(&mInfo,3,2,1);
   ogg_int64_t lastFrame = th_granule_frame(mCtx,
                                            lastGranulepos) + version_3_2_1;
   ogg_int64_t firstFrame = lastFrame - mUnstamped.Length() + 1;
   // Until we encounter a keyframe, we'll assume that the "keyframe"
   // segment of the granulepos is the first frame, or if that causes
   // the "offset" segment to overflow, we assume the required
   // keyframe is maximumally offset. Until we encounter a keyframe
   // the granulepos will probably be wrong, but we can't decode the
   // frame anyway (since we don't have its keyframe) so it doesn't really
   // matter.
   ogg_int64_t keyframe = lastGranulepos >> shift;
   // The lastFrame, firstFrame, keyframe variables, as well as the frame
   // variable in the loop below, store the frame number for Theora
   // version >= 3.2.1 streams, and store the frame index for Theora
   // version < 3.2.1 streams.
   for (uint32_t i = 0; i < mUnstamped.Length() - 1; ++i) {
     ogg_int64_t frame = firstFrame + i;
     ogg_int64_t granulepos;
     ogg_packet* packet = mUnstamped[i];
     bool isKeyframe = th_packet_iskeyframe(packet) == 1;
     if (isKeyframe) {
       granulepos = frame << shift;
       keyframe = frame;
     } else if (frame >= keyframe &&
                 frame - keyframe < ((ogg_int64_t)1 << shift))
     {
       // (frame - keyframe) won't overflow the "offset" segment of the
       // granulepos, so it's safe to calculate the granulepos.
       granulepos = (keyframe << shift) + (frame - keyframe);
     } else {
       // (frame - keyframeno) will overflow the "offset" segment of the
       // granulepos, so we take "keyframe" to be the max possible offset
       // frame instead.
       ogg_int64_t k = std::max(frame - (((ogg_int64_t)1 << shift) - 1), version_3_2_1);
       granulepos = (k << shift) + (frame - k);
     }
     // Theora 3.2.1+ granulepos store frame number [1..N], so granulepos
     // should be > 0.
     // Theora 3.2.0 granulepos store the frame index [0..(N-1)], so
     // granulepos should be >= 0.
     NS_ASSERTION(granulepos >= version_3_2_1,
                   "Invalid granulepos for Theora version");
     // Check that the frame's granule number is one more than the
     // previous frame's.
     NS_ASSERTION(i == 0 ||
                  th_granule_frame(mCtx, granulepos) ==
                  th_granule_frame(mCtx, mUnstamped[i-1]->granulepos) + 1,
                  "Granulepos calculation is incorrect!");
     packet->granulepos = granulepos;
   }
   // Check that the second to last frame's granule number is one less than
   // the last frame's (the known granule number). If not our granulepos
   // recovery missed a beat.
   NS_ASSERTION(mUnstamped.Length() < 2 ||
     th_granule_frame(mCtx, mUnstamped[mUnstamped.Length()-2]->granulepos) + 1 ==
     th_granule_frame(mCtx, lastGranulepos),
     "Granulepos recovery should catch up with packet->granulepos!");
 }
 nsresult VorbisState::Reset()
 {
   nsresult res = NS_OK;
   if (mActive && vorbis_synthesis_restart(&mDsp) != 0) {
     res = NS_ERROR_FAILURE;
   }
   if (NS_FAILED(OggCodecState::Reset())) {
     return NS_ERROR_FAILURE;
   }
   mGranulepos = 0;
   mPrevVorbisBlockSize = 0;
   return res;
 }
 VorbisState::VorbisState(ogg_page* aBosPage) :
   OggCodecState(aBosPage, true),
   mPrevVorbisBlockSize(0),
   mGranulepos(0)
 {
   MOZ_COUNT_CTOR(VorbisState);
   vorbis_info_init(&mInfo);
   vorbis_comment_init(&mComment);
   memset(&mDsp, 0, sizeof(vorbis_dsp_state));
   memset(&mBlock, 0, sizeof(vorbis_block));
 }
 VorbisState::~VorbisState() {
   MOZ_COUNT_DTOR(VorbisState);
   Reset();
   vorbis_block_clear(&mBlock);
   vorbis_dsp_clear(&mDsp);
   vorbis_info_clear(&mInfo);
   vorbis_comment_clear(&mComment);
 }
 bool VorbisState::DecodeHeader(ogg_packet* aPacket) {
   nsAutoRef<ogg_packet> autoRelease(aPacket);
   mPacketCount++;
   int ret = vorbis_synthesis_headerin(&mInfo,
                                       &mComment,
                                       aPacket);
   // We must determine when we've read the last header packet.
   // vorbis_synthesis_headerin() does not tell us when it's read the last
   // header, so we must keep track of the headers externally.
   //
   // There are 3 header packets, the Identification, Comment, and Setup
   // headers, which must be in that order. If they're out of order, the file
   // is invalid. If we've successfully read a header, and it's the setup
   // header, then we're done reading headers. The first byte of each packet
   // determines it's type as follows:
   //    0x1 -> Identification header
   //    0x3 -> Comment header
   //    0x5 -> Setup header
   // For more details of the Vorbis/Ogg containment scheme, see the Vorbis I
   // Specification, Chapter 4, Codec Setup and Packet Decode:
   // http://www.xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-580004
   bool isSetupHeader = aPacket->bytes > 0 && aPacket->packet[0] == 0x5;
   if (ret < 0 || mPacketCount > 3) {
     // We've received an error, or the first three packets weren't valid
     // header packets. Assume bad input. Our caller will deactivate the
     // bitstream.
     return false;
   } else if (ret == 0 && isSetupHeader && mPacketCount == 3) {
     // Successfully read the three header packets.
     // The bitstream remains active.
     mDoneReadingHeaders = true;
   }
   return true;
 }
 bool VorbisState::Init()
 {
   if (!mActive)
     return false;
   int ret = vorbis_synthesis_init(&mDsp, &mInfo);
   if (ret != 0) {
     NS_WARNING("vorbis_synthesis_init() failed initializing vorbis bitstream");
     return mActive = false;
   }
   ret = vorbis_block_init(&mDsp, &mBlock);
   if (ret != 0) {
     NS_WARNING("vorbis_block_init() failed initializing vorbis bitstream");
     if (mActive) {
       vorbis_dsp_clear(&mDsp);
     }
     return mActive = false;
   }
   return true;
 }
 int64_t VorbisState::Time(int64_t granulepos)
 {
   if (!mActive) {
     return -1;
   }
   return VorbisState::Time(&mInfo, granulepos);
 }
 int64_t VorbisState::Time(vorbis_info* aInfo, int64_t aGranulepos)
 {
   if (aGranulepos == -1 || aInfo->rate == 0) {
     return -1;
   }
   CheckedInt64 t = CheckedInt64(aGranulepos) * USECS_PER_S;
   if (!t.isValid())
     t = 0;
   return t.value() / aInfo->rate;
 }
 bool
 VorbisState::IsHeader(ogg_packet* aPacket)
 {
   // The first byte in each Vorbis header packet is either 0x01, 0x03, or 0x05,
   // i.e. the first bit is odd. Audio data packets have their first bit as 0x0.
   // Any packet with its first bit set cannot be a data packet, it's a
   // (possibly invalid) header packet.
   // See: http://xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-610004.2.1
   return aPacket->bytes > 0 ? (aPacket->packet[0] & 0x1) : false;
 }
 MetadataTags*
 VorbisState::GetTags()
 {
   MetadataTags* tags;
   NS_ASSERTION(mComment.user_comments, "no vorbis comment strings!");
   NS_ASSERTION(mComment.comment_lengths, "no vorbis comment lengths!");
   tags = new MetadataTags;
   for (int i = 0; i < mComment.comments; i++) {
     AddVorbisComment(tags, mComment.user_comments[i],
                      mComment.comment_lengths[i]);
   }
   return tags;
 }
 nsresult
 VorbisState::PageIn(ogg_page* aPage)
 {
   if (!mActive)
     return NS_OK;
   NS_ASSERTION(static_cast<uint32_t>(ogg_page_serialno(aPage)) == mSerial,
                "Page must be for this stream!");
   if (ogg_stream_pagein(&mState, aPage) == -1)
     return NS_ERROR_FAILURE;
   bool foundGp;
   nsresult res = PacketOutUntilGranulepos(foundGp);
   if (NS_FAILED(res))
     return res;
   if (foundGp && mDoneReadingHeaders) {
     // We've found a packet with a granulepos, and we've loaded our metadata
     // and initialized our decoder. Determine granulepos of buffered packets.
     ReconstructVorbisGranulepos();
     for (uint32_t i = 0; i < mUnstamped.Length(); ++i) {
       ogg_packet* packet = mUnstamped[i];
       AssertHasRecordedPacketSamples(packet);
       NS_ASSERTION(!IsHeader(packet), "Don't try to recover header packet gp");
       NS_ASSERTION(packet->granulepos != -1, "Packet must have gp by now");
       mPackets.Append(packet);
     }
     mUnstamped.Clear();
   }
   return NS_OK;
 }
 nsresult VorbisState::ReconstructVorbisGranulepos()
 {
   // The number of samples in a Vorbis packet is:
   // window_blocksize(previous_packet)/4+window_blocksize(current_packet)/4
   // See: http://xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-230001.3.2
   // So we maintain mPrevVorbisBlockSize, the block size of the last packet
   // encountered. We also maintain mGranulepos, which is the granulepos of
   // the last encountered packet. This enables us to give granulepos to
   // packets when the last packet in mUnstamped doesn't have a granulepos
   // (for example if the stream was truncated).
   //
   // We validate our prediction of the number of samples decoded when
   // VALIDATE_VORBIS_SAMPLE_CALCULATION is defined by recording the predicted
   // number of samples, and verifing we extract that many when decoding
   // each packet.
   NS_ASSERTION(mUnstamped.Length() > 0, "Length must be > 0");
   ogg_packet* last = mUnstamped[mUnstamped.Length()-1];
   NS_ASSERTION(last->e_o_s || last->granulepos >= 0,
     "Must know last granulepos!");
   if (mUnstamped.Length() == 1) {
     ogg_packet* packet = mUnstamped[0];
     long blockSize = vorbis_packet_blocksize(&mInfo, packet);
     if (blockSize < 0) {
       // On failure vorbis_packet_blocksize returns < 0. If we've got
       // a bad packet, we just assume that decode will have to skip this
       // packet, i.e. assume 0 samples are decodable from this packet.
       blockSize = 0;
       mPrevVorbisBlockSize = 0;
     }
     long samples = mPrevVorbisBlockSize / 4 + blockSize / 4;
     mPrevVorbisBlockSize = blockSize;
     if (packet->granulepos == -1) {
       packet->granulepos = mGranulepos + samples;
     }
     // Account for a partial last frame
     if (packet->e_o_s && packet->granulepos >= mGranulepos) {
        samples = packet->granulepos - mGranulepos;
     }
     mGranulepos = packet->granulepos;
     RecordVorbisPacketSamples(packet, samples);
     return NS_OK;
   }
   bool unknownGranulepos = last->granulepos == -1;
   int totalSamples = 0;
   for (int32_t i = mUnstamped.Length() - 1; i > 0; i--) {
     ogg_packet* packet = mUnstamped[i];
     ogg_packet* prev = mUnstamped[i-1];
     ogg_int64_t granulepos = packet->granulepos;
     NS_ASSERTION(granulepos != -1, "Must know granulepos!");
     long prevBlockSize = vorbis_packet_blocksize(&mInfo, prev);
     long blockSize = vorbis_packet_blocksize(&mInfo, packet);
     if (blockSize < 0 || prevBlockSize < 0) {
       // On failure vorbis_packet_blocksize returns < 0. If we've got
       // a bad packet, we just assume that decode will have to skip this
       // packet, i.e. assume 0 samples are decodable from this packet.
       blockSize = 0;
       prevBlockSize = 0;
     }
     long samples = prevBlockSize / 4 + blockSize / 4;
     totalSamples += samples;
     prev->granulepos = granulepos - samples;
     RecordVorbisPacketSamples(packet, samples);
   }
   if (unknownGranulepos) {
     for (uint32_t i = 0; i < mUnstamped.Length(); i++) {
       ogg_packet* packet = mUnstamped[i];
       packet->granulepos += mGranulepos + totalSamples + 1;
     }
   }
   ogg_packet* first = mUnstamped[0];
   long blockSize = vorbis_packet_blocksize(&mInfo, first);
   if (blockSize < 0) {
     mPrevVorbisBlockSize = 0;
     blockSize = 0;
   }
   long samples = (mPrevVorbisBlockSize == 0) ? 0 :
                   mPrevVorbisBlockSize / 4 + blockSize / 4;
   int64_t start = first->granulepos - samples;
   RecordVorbisPacketSamples(first, samples);
   if (last->e_o_s && start < mGranulepos) {
     // We've calculated that there are more samples in this page than its
     // granulepos claims, and it's the last page in the stream. This is legal,
     // and we will need to prune the trailing samples when we come to decode it.
     // We must correct the timestamps so that they follow the last Vorbis page's
     // samples.
     int64_t pruned = mGranulepos - start;
     for (uint32_t i = 0; i < mUnstamped.Length() - 1; i++) {
       mUnstamped[i]->granulepos += pruned;
     }
 #ifdef VALIDATE_VORBIS_SAMPLE_CALCULATION
     mVorbisPacketSamples[last] -= pruned;
 #endif
   }
   mPrevVorbisBlockSize = vorbis_packet_blocksize(&mInfo, last);
   mPrevVorbisBlockSize = std::max(static_cast<long>(0), mPrevVorbisBlockSize);
   mGranulepos = last->granulepos;
   return NS_OK;
 }
 #ifdef MOZ_OPUS
 OpusState::OpusState(ogg_page* aBosPage) :
   OggCodecState(aBosPage, true),
   mParser(nullptr),
   mDecoder(nullptr),
   mSkip(0),
   mPrevPacketGranulepos(0),
   mPrevPageGranulepos(0)
 {
   MOZ_COUNT_CTOR(OpusState);
 }
 OpusState::~OpusState() {
   MOZ_COUNT_DTOR(OpusState);
   Reset();
   if (mDecoder) {
     opus_multistream_decoder_destroy(mDecoder);
     mDecoder = nullptr;
   }
 }
 nsresult OpusState::Reset()
 {
   return Reset(false);
 }
 nsresult OpusState::Reset(bool aStart)
 {
   nsresult res = NS_OK;
   if (mActive && mDecoder) {
     // Reset the decoder.
     opus_multistream_decoder_ctl(mDecoder, OPUS_RESET_STATE);
     // Let the seek logic handle pre-roll if we're not seeking to the start.
     mSkip = aStart ? mParser->mPreSkip : 0;
     // This lets us distinguish the first page being the last page vs. just
     // not having processed the previous page when we encounter the last page.
     mPrevPageGranulepos = aStart ? 0 : -1;
     mPrevPacketGranulepos = aStart ? 0 : -1;
   }
   // Clear queued data.
   if (NS_FAILED(OggCodecState::Reset())) {
     return NS_ERROR_FAILURE;
   }
   LOG(PR_LOG_DEBUG, ("Opus decoder reset, to skip %d", mSkip));
   return res;
 }
 bool OpusState::Init(void)
 {
   if (!mActive)
     return false;
   int error;
   NS_ASSERTION(mDecoder == nullptr, "leaking OpusDecoder");
   mDecoder = opus_multistream_decoder_create(mParser->mRate,
                                              mParser->mChannels,
                                              mParser->mStreams,
                                              mParser->mCoupledStreams,
                                              mParser->mMappingTable,
                                              &error);
   mSkip = mParser->mPreSkip;
   LOG(PR_LOG_DEBUG, ("Opus decoder init, to skip %d", mSkip));
   return error == OPUS_OK;
 }
 bool OpusState::DecodeHeader(ogg_packet* aPacket)
 {
   nsAutoRef<ogg_packet> autoRelease(aPacket);
   switch(mPacketCount++) {
     // Parse the id header.
     case 0: {
         mParser = new OpusParser;
         if(!mParser->DecodeHeader(aPacket->packet, aPacket->bytes)) {
           return false;
         }
         mRate = mParser->mRate;
         mChannels = mParser->mChannels;
         mPreSkip = mParser->mPreSkip;
 #ifdef MOZ_SAMPLE_TYPE_FLOAT32
         mGain = mParser->mGain;
 #else
         mGain_Q16 = mParser->mGain_Q16;
 #endif
     }
     break;
     // Parse the metadata header.
     case 1: {
         if(!mParser->DecodeTags(aPacket->packet, aPacket->bytes)) {
           return false;
         }
     }
     break;
     // We made it to the first data packet (which includes reconstructing
     // timestamps for it in PageIn). Success!
     default: {
       mDoneReadingHeaders = true;
       // Put it back on the queue so we can decode it.
       mPackets.PushFront(autoRelease.disown());
     }
     break;
   }
   return true;
 }
 /* Construct and return a tags hashmap from our internal array */
 MetadataTags* OpusState::GetTags()
 {
   MetadataTags* tags;
   tags = new MetadataTags;
   for (uint32_t i = 0; i < mParser->mTags.Length(); i++) {
     AddVorbisComment(tags, mParser->mTags[i].Data(), mParser->mTags[i].Length());
   }
   return tags;
 }
 /* Return the timestamp (in microseconds) equivalent to a granulepos. */
 int64_t OpusState::Time(int64_t aGranulepos)
 {
   if (!mActive)
     return -1;
   return Time(mParser->mPreSkip, aGranulepos);
 }
 int64_t OpusState::Time(int aPreSkip, int64_t aGranulepos)
 {
   if (aGranulepos < 0)
     return -1;
   // Ogg Opus always runs at a granule rate of 48 kHz.
   CheckedInt64 t = CheckedInt64(aGranulepos - aPreSkip) * USECS_PER_S;
   return t.isValid() ? t.value() / 48000 : -1;
 }
 bool OpusState::IsHeader(ogg_packet* aPacket)
 {
   return aPacket->bytes >= 16 &&
          (!memcmp(aPacket->packet, "OpusHead", 8) ||
           !memcmp(aPacket->packet, "OpusTags", 8));
 }
 nsresult OpusState::PageIn(ogg_page* aPage)
 {
   if (!mActive)
     return NS_OK;
   NS_ASSERTION(static_cast<uint32_t>(ogg_page_serialno(aPage)) == mSerial,
                "Page must be for this stream!");
   if (ogg_stream_pagein(&mState, aPage) == -1)
     return NS_ERROR_FAILURE;
   bool haveGranulepos;
   nsresult rv = PacketOutUntilGranulepos(haveGranulepos);
   if (NS_FAILED(rv) || !haveGranulepos || mPacketCount < 2)
     return rv;
   if(!ReconstructOpusGranulepos())
     return NS_ERROR_FAILURE;
   for (uint32_t i = 0; i < mUnstamped.Length(); i++) {
     ogg_packet* packet = mUnstamped[i];
     NS_ASSERTION(!IsHeader(packet), "Don't try to play a header packet");
     NS_ASSERTION(packet->granulepos != -1, "Packet should have a granulepos");
     mPackets.Append(packet);
   }
   mUnstamped.Clear();
   return NS_OK;
 }
 // Helper method to return the change in granule position due to an Opus packet
 // (as distinct from the number of samples in the packet, which depends on the
 // decoder rate). It should work with a multistream Opus file, and continue to
 // work should we ever allow the decoder to decode at a rate other than 48 kHz.
 // It even works before we've created the actual Opus decoder.
 static int GetOpusDeltaGP(ogg_packet* packet)
 {
   int nframes;
   nframes = opus_packet_get_nb_frames(packet->packet, packet->bytes);
   if (nframes > 0) {
     return nframes*opus_packet_get_samples_per_frame(packet->packet, 48000);
   }
   NS_WARNING("Invalid Opus packet.");
   return nframes;
 }
 bool OpusState::ReconstructOpusGranulepos(void)
 {
   NS_ASSERTION(mUnstamped.Length() > 0, "Must have unstamped packets");
   ogg_packet* last = mUnstamped[mUnstamped.Length()-1];
   NS_ASSERTION(last->e_o_s || last->granulepos > 0,
       "Must know last granulepos!");
   int64_t gp;
   // If this is the last page, and we've seen at least one previous page (or
   // this is the first page)...
   if (last->e_o_s) {
     if (mPrevPageGranulepos != -1) {
       // If this file only has one page and the final granule position is
       // smaller than the pre-skip amount, we MUST reject the stream.
       if (!mDoneReadingHeaders && last->granulepos < mPreSkip)
         return false;
       int64_t last_gp = last->granulepos;
       gp = mPrevPageGranulepos;
       // Loop through the packets forwards, adding the current packet's
       // duration to the previous granulepos to get the value for the
       // current packet.
       for (uint32_t i = 0; i < mUnstamped.Length() - 1; ++i) {
         ogg_packet* packet = mUnstamped[i];
         int offset = GetOpusDeltaGP(packet);
         // Check for error (negative offset) and overflow.
         if (offset >= 0 && gp <= INT64_MAX - offset) {
           gp += offset;
           if (gp >= last_gp) {
             NS_WARNING("Opus end trimming removed more than a full packet.");
             // We were asked to remove a full packet's worth of data or more.
             // Encoders SHOULD NOT produce streams like this, but we'll handle
             // it for them anyway.
             gp = last_gp;
             for (uint32_t j = i+1; j < mUnstamped.Length(); ++j) {
               OggCodecState::ReleasePacket(mUnstamped[j]);
             }
             mUnstamped.RemoveElementsAt(i+1, mUnstamped.Length() - (i+1));
             last = packet;
             last->e_o_s = 1;
           }
         }
         packet->granulepos = gp;
       }
       mPrevPageGranulepos = last_gp;
       return true;
     } else {
       NS_WARNING("No previous granule position to use for Opus end trimming.");
       // If we don't have a previous granule position, fall through.
       // We simply won't trim any samples from the end.
       // TODO: Are we guaranteed to have seen a previous page if there is one?
     }
   }
   gp = last->granulepos;
   // Loop through the packets backwards, subtracting the next
   // packet's duration from its granulepos to get the value
   // for the current packet.
   for (uint32_t i = mUnstamped.Length() - 1; i > 0; i--) {
     int offset = GetOpusDeltaGP(mUnstamped[i]);
     // Check for error (negative offset) and overflow.
     if (offset >= 0) {
       if (offset <= gp) {
         gp -= offset;
       } else {
         // If the granule position of the first data page is smaller than the
         // number of decodable audio samples on that page, then we MUST reject
         // the stream.
         if (!mDoneReadingHeaders)
           return false;
         // It's too late to reject the stream.
         // If we get here, this almost certainly means the file has screwed-up
         // timestamps somewhere after the first page.
         NS_WARNING("Clamping negative Opus granulepos to zero.");
         gp = 0;
       }
     }
     mUnstamped[i - 1]->granulepos = gp;
   }
   // Check to make sure the first granule position is at least as large as the
   // total number of samples decodable from the first page with completed
   // packets. This requires looking at the duration of the first packet, too.
   // We MUST reject such streams.
   if (!mDoneReadingHeaders && GetOpusDeltaGP(mUnstamped[0]) > gp)
     return false;
   mPrevPageGranulepos = last->granulepos;
   return true;
 }
 #endif /* MOZ_OPUS */
 SkeletonState::SkeletonState(ogg_page* aBosPage) :
   OggCodecState(aBosPage, true),
   mVersion(0),
   mPresentationTime(0),
   mLength(0)
 {
   MOZ_COUNT_CTOR(SkeletonState);
 }
 SkeletonState::~SkeletonState()
 {
   MOZ_COUNT_DTOR(SkeletonState);
 }
 // Support for Ogg Skeleton 4.0, as per specification at:
 // http://wiki.xiph.org/Ogg_Skeleton_4
 // Minimum length in bytes of a Skeleton header packet.
 static const long SKELETON_MIN_HEADER_LEN = 28;
 static const long SKELETON_4_0_MIN_HEADER_LEN = 80;
 // Minimum length in bytes of a Skeleton 4.0 index packet.
 static const long SKELETON_4_0_MIN_INDEX_LEN = 42;
 // Minimum possible size of a compressed index keypoint.
 static const size_t MIN_KEY_POINT_SIZE = 2;
 // Byte offset of the major and minor version numbers in the
 // Ogg Skeleton 4.0 header packet.
 static const size_t SKELETON_VERSION_MAJOR_OFFSET = 8;
 static const size_t SKELETON_VERSION_MINOR_OFFSET = 10;
 // Byte-offsets of the presentation time numerator and denominator
 static const size_t SKELETON_PRESENTATION_TIME_NUMERATOR_OFFSET = 12;
 static const size_t SKELETON_PRESENTATION_TIME_DENOMINATOR_OFFSET = 20;
 // Byte-offsets of the length of file field in the Skeleton 4.0 header packet.
 static const size_t SKELETON_FILE_LENGTH_OFFSET = 64;
 // Byte-offsets of the fields in the Skeleton index packet.
 static const size_t INDEX_SERIALNO_OFFSET = 6;
 static const size_t INDEX_NUM_KEYPOINTS_OFFSET = 10;
 static const size_t INDEX_TIME_DENOM_OFFSET = 18;
 static const size_t INDEX_FIRST_NUMER_OFFSET = 26;
 static const size_t INDEX_LAST_NUMER_OFFSET = 34;
 static const size_t INDEX_KEYPOINT_OFFSET = 42;
 static bool IsSkeletonBOS(ogg_packet* aPacket)
 {
   return aPacket->bytes >= SKELETON_MIN_HEADER_LEN &&
          memcmp(reinterpret_cast<char*>(aPacket->packet), "fishead", 8) == 0;
 }
 static bool IsSkeletonIndex(ogg_packet* aPacket)
 {
   return aPacket->bytes >= SKELETON_4_0_MIN_INDEX_LEN &&
          memcmp(reinterpret_cast<char*>(aPacket->packet), "index", 5) == 0;
 }
 // Reads a variable length encoded integer at p. Will not read
 // past aLimit. Returns pointer to character after end of integer.
 static const unsigned char* ReadVariableLengthInt(const unsigned char* p,
                                                   const unsigned char* aLimit,
                                                   int64_t& n)
 {
   int shift = 0;
   int64_t byte = 0;
   n = 0;
   while (p < aLimit &&
          (byte & 0x80) != 0x80 &&
          shift < 57)
   {
     byte = static_cast<int64_t>(*p);
     n |= ((byte & 0x7f) << shift);
     shift += 7;
     p++;
   }
   return p;
 }
 bool SkeletonState::DecodeIndex(ogg_packet* aPacket)
 {
   NS_ASSERTION(aPacket->bytes >= SKELETON_4_0_MIN_INDEX_LEN,
                "Index must be at least minimum size");
   if (!mActive) {
     return false;
   }
   uint32_t serialno = LittleEndian::readUint32(aPacket->packet + INDEX_SERIALNO_OFFSET);
   int64_t numKeyPoints = LittleEndian::readInt64(aPacket->packet + INDEX_NUM_KEYPOINTS_OFFSET);
   int64_t endTime = 0, startTime = 0;
   const unsigned char* p = aPacket->packet;
   int64_t timeDenom = LittleEndian::readInt64(aPacket->packet + INDEX_TIME_DENOM_OFFSET);
   if (timeDenom == 0) {
     LOG(PR_LOG_DEBUG, ("Ogg Skeleton Index packet for stream %u has 0 "
                        "timestamp denominator.", serialno));
     return (mActive = false);
   }
   // Extract the start time.
   CheckedInt64 t = CheckedInt64(LittleEndian::readInt64(p + INDEX_FIRST_NUMER_OFFSET)) * USECS_PER_S;
   if (!t.isValid()) {
     return (mActive = false);
   } else {
     startTime = t.value() / timeDenom;
   }
   // Extract the end time.
   t = LittleEndian::readInt64(p + INDEX_LAST_NUMER_OFFSET) * USECS_PER_S;
   if (!t.isValid()) {
     return (mActive = false);
   } else {
     endTime = t.value() / timeDenom;
   }
   // Check the numKeyPoints value read, ensure we're not going to run out of
   // memory while trying to decode the index packet.
   CheckedInt64 minPacketSize = (CheckedInt64(numKeyPoints) * MIN_KEY_POINT_SIZE) + INDEX_KEYPOINT_OFFSET;
   if (!minPacketSize.isValid())
   {
     return (mActive = false);
   }
   int64_t sizeofIndex = aPacket->bytes - INDEX_KEYPOINT_OFFSET;
   int64_t maxNumKeyPoints = sizeofIndex / MIN_KEY_POINT_SIZE;
   if (aPacket->bytes < minPacketSize.value() ||
       numKeyPoints > maxNumKeyPoints ||
       numKeyPoints < 0)
   {
     // Packet size is less than the theoretical minimum size, or the packet is
     // claiming to store more keypoints than it's capable of storing. This means
     // that the numKeyPoints field is too large or small for the packet to
     // possibly contain as many packets as it claims to, so the numKeyPoints
     // field is possibly malicious. Don't try decoding this index, we may run
     // out of memory.
     LOG(PR_LOG_DEBUG, ("Possibly malicious number of key points reported "
                        "(%lld) in index packet for stream %u.",
                        numKeyPoints,
                        serialno));
     return (mActive = false);
   }
   nsAutoPtr<nsKeyFrameIndex> keyPoints(new nsKeyFrameIndex(startTime, endTime));
   p = aPacket->packet + INDEX_KEYPOINT_OFFSET;
   const unsigned char* limit = aPacket->packet + aPacket->bytes;
   int64_t numKeyPointsRead = 0;
   CheckedInt64 offset = 0;
   CheckedInt64 time = 0;
   while (p < limit &&
          numKeyPointsRead < numKeyPoints)
   {
     int64_t delta = 0;
     p = ReadVariableLengthInt(p, limit, delta);
     offset += delta;
     if (p == limit ||
         !offset.isValid() ||
         offset.value() > mLength ||
         offset.value() < 0)
     {
       return (mActive = false);
     }
     p = ReadVariableLengthInt(p, limit, delta);
     time += delta;
     if (!time.isValid() ||
         time.value() > endTime ||
         time.value() < startTime)
     {
       return (mActive = false);
     }
     CheckedInt64 timeUsecs = time * USECS_PER_S;
     if (!timeUsecs.isValid())
       return mActive = false;
     timeUsecs /= timeDenom;
     keyPoints->Add(offset.value(), timeUsecs.value());
     numKeyPointsRead++;
   }
   int32_t keyPointsRead = keyPoints->Length();
   if (keyPointsRead > 0) {
     mIndex.Put(serialno, keyPoints.forget());
   }
   LOG(PR_LOG_DEBUG, ("Loaded %d keypoints for Skeleton on stream %u",
                      keyPointsRead, serialno));
   return true;
 }
 nsresult SkeletonState::IndexedSeekTargetForTrack(uint32_t aSerialno,
                                                     int64_t aTarget,
                                                     nsKeyPoint& aResult)
 {
   nsKeyFrameIndex* index = nullptr;
   mIndex.Get(aSerialno, &index);
   if (!index ||
       index->Length() == 0 ||
       aTarget < index->mStartTime ||
       aTarget > index->mEndTime)
   {
     return NS_ERROR_FAILURE;
   }
   // Binary search to find the last key point with time less than target.
   int start = 0;
   int end = index->Length() - 1;
   while (end > start) {
     int mid = start + ((end - start + 1) >> 1);
     if (index->Get(mid).mTime == aTarget) {
        start = mid;
        break;
     } else if (index->Get(mid).mTime < aTarget) {
       start = mid;
     } else {
       end = mid - 1;
     }
   }
   aResult = index->Get(start);
   NS_ASSERTION(aResult.mTime <= aTarget, "Result should have time <= target");
   return NS_OK;
 }
 nsresult SkeletonState::IndexedSeekTarget(int64_t aTarget,
                                             nsTArray<uint32_t>& aTracks,
                                             nsSeekTarget& aResult)
 {
   if (!mActive || mVersion < SKELETON_VERSION(4,0)) {
     return NS_ERROR_FAILURE;
   }
   // Loop over all requested tracks' indexes, and get the keypoint for that
   // seek target. Record the keypoint with the lowest offset, this will be
   // our seek result. User must seek to the one with lowest offset to ensure we
   // pass "keyframes" on all tracks when we decode forwards to the seek target.
   nsSeekTarget r;
   for (uint32_t i=0; i<aTracks.Length(); i++) {
     nsKeyPoint k;
     if (NS_SUCCEEDED(IndexedSeekTargetForTrack(aTracks[i], aTarget, k)) &&
         k.mOffset < r.mKeyPoint.mOffset)
     {
       r.mKeyPoint = k;
       r.mSerial = aTracks[i];
     }
   }
   if (r.IsNull()) {
     return NS_ERROR_FAILURE;
   }
   LOG(PR_LOG_DEBUG, ("Indexed seek target for time %lld is offset %lld",
                      aTarget, r.mKeyPoint.mOffset));
   aResult = r;
   return NS_OK;
 }
 nsresult SkeletonState::GetDuration(const nsTArray<uint32_t>& aTracks,
                                       int64_t& aDuration)
 {
   if (!mActive ||
       mVersion < SKELETON_VERSION(4,0) ||
       !HasIndex() ||
       aTracks.Length() == 0)
   {
     return NS_ERROR_FAILURE;
   }
   int64_t endTime = INT64_MIN;
   int64_t startTime = INT64_MAX;
   for (uint32_t i=0; i<aTracks.Length(); i++) {
     nsKeyFrameIndex* index = nullptr;
     mIndex.Get(aTracks[i], &index);
     if (!index) {
       // Can't get the timestamps for one of the required tracks, fail.
       return NS_ERROR_FAILURE;
     }
     if (index->mEndTime > endTime) {
       endTime = index->mEndTime;
     }
     if (index->mStartTime < startTime) {
       startTime = index->mStartTime;
     }
   }
   NS_ASSERTION(endTime > startTime, "Duration must be positive");
   CheckedInt64 duration = CheckedInt64(endTime) - startTime;
   aDuration = duration.isValid() ? duration.value() : 0;
   return duration.isValid() ? NS_OK : NS_ERROR_FAILURE;
 }
 bool SkeletonState::DecodeHeader(ogg_packet* aPacket)
 {
   nsAutoRef<ogg_packet> autoRelease(aPacket);
   if (IsSkeletonBOS(aPacket)) {
     uint16_t verMajor = LittleEndian::readUint16(aPacket->packet + SKELETON_VERSION_MAJOR_OFFSET);
     uint16_t verMinor = LittleEndian::readUint16(aPacket->packet + SKELETON_VERSION_MINOR_OFFSET);
     // Read the presentation time. We read this before the version check as the
     // presentation time exists in all versions.
     int64_t n = LittleEndian::readInt64(aPacket->packet + SKELETON_PRESENTATION_TIME_NUMERATOR_OFFSET);
     int64_t d = LittleEndian::readInt64(aPacket->packet + SKELETON_PRESENTATION_TIME_DENOMINATOR_OFFSET);
     mPresentationTime = d == 0 ? 0 : (static_cast<float>(n) / static_cast<float>(d)) * USECS_PER_S;
     mVersion = SKELETON_VERSION(verMajor, verMinor);
     // We can only care to parse Skeleton version 4.0+.
     if (mVersion < SKELETON_VERSION(4,0) ||
         mVersion >= SKELETON_VERSION(5,0) ||
         aPacket->bytes < SKELETON_4_0_MIN_HEADER_LEN)
       return false;
     // Extract the segment length.
     mLength = LittleEndian::readInt64(aPacket->packet + SKELETON_FILE_LENGTH_OFFSET);
     LOG(PR_LOG_DEBUG, ("Skeleton segment length: %lld", mLength));
     // Initialize the serialno-to-index map.
     return true;
   } else if (IsSkeletonIndex(aPacket) && mVersion >= SKELETON_VERSION(4,0)) {
     return DecodeIndex(aPacket);
   } else if (aPacket->e_o_s) {
     mDoneReadingHeaders = true;
     return true;
   }
   return true;
 }
 } // namespace mozilla

The Tor Browser / annotate

content/media/ogg/OggCodecState.cpp@97036ab72558 (annotated)

content/media/ogg/OggCodecState.cpp