C++ nsACString::EqualsASCII方法代码示例

/* static */
bool MP3Decoder::CanHandleMediaType(const nsACString& aType,
                                    const nsAString& aCodecs)
{
  if (aType.EqualsASCII("audio/mp3") || aType.EqualsASCII("audio/mpeg")) {
    return IsEnabled() &&
      (aCodecs.IsEmpty() || aCodecs.EqualsASCII("mp3"));
  }
  return false;
}

bool
WMFDecoder::GetSupportedCodecs(const nsACString& aType,
                               char const *const ** aCodecList)
{
  if (!MediaDecoder::IsWMFEnabled() ||
      NS_FAILED(LoadDLLs()))
    return false;

  // MP3 is specified to have no codecs in its "type" param:
  // http://wiki.whatwg.org/wiki/Video_type_parameters#MPEG
  // So specify an empty codecs list, so that if script specifies 
  // a "type" param with codecs, it will be reported as not supported
  // as per the spec.
  static char const *const mp3AudioCodecs[] = {
    nullptr
  };
  if (aType.EqualsASCII("audio/mpeg")) {
    if (aCodecList) {
      *aCodecList = mp3AudioCodecs;
    }
    // Assume that if LoadDLLs() didn't fail, we can decode MP3.
    return true;
  }

  // AAC in M4A.
  static char const *const aacAudioCodecs[] = {
    "mp4a.40.2",    // AAC-LC
    nullptr
  };
  if (aType.EqualsASCII("audio/mp4")) {
    if (aCodecList) {
      *aCodecList = aacAudioCodecs;
    }
    return true;
  }

  // H.264 + AAC in MP4.
  static char const *const H264Codecs[] = {
    "avc1.42E01E",  // H.264 Constrained Baseline Profile Level 3.0
    "avc1.42001E",  // H.264 Baseline Profile Level 3.0
    "avc1.58A01E",  // H.264 Extended Profile Level 3.0
    "avc1.4D401E",  // H.264 Main Profile Level 3.0
    "avc1.64001E",  // H.264 High Profile Level 3.0
    "avc1.64001F",  // H.264 High Profile Level 3.1
    "mp4a.40.2",    // AAC-LC
    nullptr
  };
  if (aType.EqualsASCII("video/mp4")) {
    if (aCodecList) {
      *aCodecList = H264Codecs;
    }
    return true;
  }

  return false;
}

/* static */ bool
ADTSDecoder::CanHandleMediaType(const nsACString& aType,
                                const nsAString& aCodecs)
{
  if (aType.EqualsASCII("audio/aac") || aType.EqualsASCII("audio/aacp")) {
    return IsEnabled() && (aCodecs.IsEmpty() || aCodecs.EqualsASCII("aac"));
  }

  return false;
}

bool
WMFDecoder::GetSupportedCodecs(const nsACString& aType,
                               char const *const ** aCodecList)
{
  if (!MediaDecoder::IsWMFEnabled() ||
      NS_FAILED(LoadDLLs()))
    return false;

  // Assume that if LoadDLLs() didn't fail, we can playback the types that
  // we know should be supported on Windows 7+ using WMF.
  static char const *const mp3AudioCodecs[] = {
    "mp3",
    nullptr
  };
  if (aType.EqualsASCII("audio/mpeg") ||
      aType.EqualsASCII("audio/mp3")) {
    if (aCodecList) {
      *aCodecList = mp3AudioCodecs;
    }
    return true;
  }

  // AAC in M4A.
  static char const *const aacAudioCodecs[] = {
    "mp4a.40.2",    // AAC-LC
    nullptr
  };
  if (aType.EqualsASCII("audio/mp4") ||
      aType.EqualsASCII("audio/x-m4a")) {
    if (aCodecList) {
      *aCodecList = aacAudioCodecs;
    }
    return true;
  }

  // H.264 + AAC in MP4.
  static char const *const H264Codecs[] = {
    "avc1.42E01E",  // H.264 Constrained Baseline Profile Level 3.0
    "avc1.42001E",  // H.264 Baseline Profile Level 3.0
    "avc1.58A01E",  // H.264 Extended Profile Level 3.0
    "avc1.4D401E",  // H.264 Main Profile Level 3.0
    "avc1.64001E",  // H.264 High Profile Level 3.0
    "avc1.64001F",  // H.264 High Profile Level 3.1
    "mp4a.40.2",    // AAC-LC
    nullptr
  };
  if (aType.EqualsASCII("video/mp4")) {
    if (aCodecList) {
      *aCodecList = H264Codecs;
    }
    return true;
  }

  return false;
}

/* static */
bool
WaveDecoder::CanHandleMediaType(const nsACString& aType,
                               const nsAString& aCodecs)
{
  if (aType.EqualsASCII("audio/wave") || aType.EqualsASCII("audio/x-wav") ||
      aType.EqualsASCII("audio/wav")  || aType.EqualsASCII("audio/x-pn-wav")) {
    return IsEnabled() && (aCodecs.IsEmpty() || aCodecs.EqualsASCII("1"));
  }

  return false;
}

/* static */
bool
MP4Decoder::CanHandleMediaType(const nsACString& aType,
                               const nsAString& aCodecs,
                               bool& aOutContainsAAC,
                               bool& aOutContainsH264,
                               bool& aOutContainsMP3)
{
  if (!IsEnabled()) {
    return false;
  }

  if (aType.EqualsASCII("audio/mp4") || aType.EqualsASCII("audio/x-m4a")) {
    return MP4Decoder::CanCreateAACDecoder() &&
           (aCodecs.IsEmpty() ||
            IsSupportedAudioCodec(aCodecs,
                                  aOutContainsAAC,
                                  aOutContainsMP3));
  }

#ifdef MOZ_GONK_MEDIACODEC
  if (aType.EqualsASCII(VIDEO_3GPP)) {
    return Preferences::GetBool("media.fragmented-mp4.gonk.enabled", false);
  }
#endif
  if ((!aType.EqualsASCII("video/mp4") && !aType.EqualsASCII("video/x-m4v")) ||
      !MP4Decoder::CanCreateH264Decoder()) {
    return false;
  }

  // Verify that all the codecs specifed are ones that we expect that
  // we can play.
  nsCharSeparatedTokenizer tokenizer(aCodecs, ',');
  bool expectMoreTokens = false;
  while (tokenizer.hasMoreTokens()) {
    const nsSubstring& token = tokenizer.nextToken();
    expectMoreTokens = tokenizer.separatorAfterCurrentToken();
    if (IsSupportedAudioCodec(token,
                              aOutContainsAAC,
                              aOutContainsMP3)) {
      continue;
    }
    if (IsSupportedH264Codec(token)) {
      aOutContainsH264 = true;
      continue;
    }
    return false;
  }
  if (expectMoreTokens) {
    // Last codec name was empty
    return false;
  }

  return true;
}

bool
WMFDecoder::CanPlayType(const nsACString& aType,
                        const nsAString& aCodecs)
{
  if (!MediaDecoder::IsWMFEnabled() ||
      NS_FAILED(LoadDLLs())) {
    return false;
  }

  // Assume that if LoadDLLs() didn't fail, we can playback the types that
  // we know should be supported by Windows Media Foundation.
  if ((aType.EqualsASCII("audio/mpeg") || aType.EqualsASCII("audio/mp3")) &&
      IsMP3Supported()) {
    // Note: We block MP3 playback on Window 7 SP0 since it seems to crash
    // in some circumstances.
    return !aCodecs.Length() || aCodecs.EqualsASCII("mp3");
  }

  // AAC-LC or MP3 in M4A.
  if (aType.EqualsASCII("audio/mp4") || aType.EqualsASCII("audio/x-m4a")) {
    return !aCodecs.Length() ||
           aCodecs.EqualsASCII("mp4a.40.2") ||
           aCodecs.EqualsASCII("mp3");
  }

  if (!aType.EqualsASCII("video/mp4")) {
    return false;
  }

  // H.264 + AAC in MP4. Verify that all the codecs specifed are ones that
  // we expect that we can play.
  nsCharSeparatedTokenizer tokenizer(aCodecs, ',');
  bool expectMoreTokens = false;
  while (tokenizer.hasMoreTokens()) {
    const nsSubstring& token = tokenizer.nextToken();
    expectMoreTokens = tokenizer.separatorAfterCurrentToken();
    if (token.EqualsASCII("mp4a.40.2") || // AAC-LC
        token.EqualsASCII("mp3") ||
        IsSupportedH264Codec(token)) {
      continue;
    }
    return false;
  }
  if (expectMoreTokens) {
    // Last codec name was empty
    return false;
  }
  return true;
}

/* static */
bool DecoderTraits::IsSupportedInVideoDocument(const nsACString& aType)
{
  return
#ifdef MOZ_OGG
    IsOggType(aType) ||
#endif
#ifdef MOZ_OMX_DECODER
    // We support amr inside WebApps on firefoxOS but not in general web content.
    // Ensure we dont create a VideoDocument when accessing amr URLs directly.
    (IsOmxSupportedType(aType) && !aType.EqualsASCII("audio/amr")) ||
#endif
#ifdef MOZ_WEBM
    IsWebMType(aType) ||
#endif
#ifdef MOZ_DASH
    IsDASHMPDType(aType) ||
#endif
#ifdef MOZ_GSTREAMER
    IsGStreamerSupportedType(aType) ||
#endif
#ifdef MOZ_MEDIA_PLUGINS
    (MediaDecoder::IsMediaPluginsEnabled() && IsMediaPluginsType(aType)) ||
#endif
#ifdef MOZ_WMF
    (IsWMFSupportedType(aType) &&
     Preferences::GetBool("media.windows-media-foundation.play-stand-alone", true)) ||
#endif
#ifdef MOZ_DIRECTSHOW
    IsDirectShowSupportedType(aType) ||
#endif
#ifdef MOZ_APPLEMEDIA
    IsAppleMediaSupportedType(aType) ||
#endif
    false;
}

/* static */
bool
MP4Decoder::CanHandleMediaType(const nsACString& aType,
                               const nsAString& aCodecs,
                               bool& aOutContainsAAC,
                               bool& aOutContainsH264,
                               bool& aOutContainsMP3)
{
  if (!IsEnabled()) {
    return false;
  }

  if (aType.EqualsASCII("audio/mp4") || aType.EqualsASCII("audio/x-m4a")) {
    return aCodecs.IsEmpty() ||
           IsSupportedAudioCodec(aCodecs,
                                 aOutContainsAAC,
                                 aOutContainsMP3);
  }

  if (!aType.EqualsASCII("video/mp4")) {
    return false;
  }

  // Verify that all the codecs specifed are ones that we expect that
  // we can play.
  nsCharSeparatedTokenizer tokenizer(aCodecs, ',');
  bool expectMoreTokens = false;
  while (tokenizer.hasMoreTokens()) {
    const nsSubstring& token = tokenizer.nextToken();
    expectMoreTokens = tokenizer.separatorAfterCurrentToken();
    if (IsSupportedAudioCodec(token,
                              aOutContainsAAC,
                              aOutContainsMP3)) {
      continue;
    }
    if (IsSupportedH264Codec(token)) {
      aOutContainsH264 = true;
      continue;
    }
    return false;
  }
  if (expectMoreTokens) {
    // Last codec name was empty
    return false;
  }

  return true;
}

/* static */
bool
OggDecoder::CanHandleMediaType(const nsACString& aMIMETypeExcludingCodecs,
                               const nsAString& aCodecs)
{
  if (!IsEnabled()) {
    return false;
  }

  const bool isOggAudio = aMIMETypeExcludingCodecs.EqualsASCII("audio/ogg");
  const bool isOggVideo =
    aMIMETypeExcludingCodecs.EqualsASCII("video/ogg") ||
    aMIMETypeExcludingCodecs.EqualsASCII("application/ogg");

  if (!isOggAudio && !isOggVideo) {
    return false;
  }

  nsTArray<nsCString> codecMimes;
  if (aCodecs.IsEmpty()) {
    // WebM guarantees that the only codecs it contained are vp8, vp9, opus or vorbis.
    return true;
  }
  // Verify that all the codecs specified are ones that we expect that
  // we can play.
  nsTArray<nsString> codecs;
  if (!ParseCodecsString(aCodecs, codecs)) {
    return false;
  }
  for (const nsString& codec : codecs) {
    if ((IsOpusEnabled() && codec.EqualsLiteral("opus")) ||
        codec.EqualsLiteral("vorbis") ||
        (MediaPrefs::FlacInOgg() && codec.EqualsLiteral("flac"))) {
      continue;
    }
    // Note: Only accept Theora in a video content type, not in an audio
    // content type.
    if (isOggVideo && codec.EqualsLiteral("theora")) {
      continue;
    }
    // Some unsupported codec.
    return false;
  }
  return true;
}

bool
ServiceWorkerRegistrar::IsSupportedVersion(const nsACString& aVersion) const
{
    uint32_t numVersions = ArrayLength(gSupportedRegistrarVersions);
    for (uint32_t i = 0; i < numVersions; i++) {
        if (aVersion.EqualsASCII(gSupportedRegistrarVersions[i])) {
            return true;
        }
    }
    return false;
}

/* static */
bool
WebMDecoder::CanHandleMediaType(const nsACString& aMIMETypeExcludingCodecs,
                                const nsAString& aCodecs)
{
  if (!IsEnabled()) {
    return false;
  }

  const bool isWebMAudio = aMIMETypeExcludingCodecs.EqualsASCII("audio/webm");
  const bool isWebMVideo = aMIMETypeExcludingCodecs.EqualsASCII("video/webm");
  if (!isWebMAudio && !isWebMVideo) {
    return false;
  }

  nsTArray<nsCString> codecMimes;
  if (aCodecs.IsEmpty()) {
    // WebM guarantees that the only codecs it contained are vp8, vp9, opus or vorbis.
    return true;
  }
  // Verify that all the codecs specified are ones that we expect that
  // we can play.
  nsTArray<nsString> codecs;
  if (!ParseCodecsString(aCodecs, codecs)) {
    return false;
  }
  for (const nsString& codec : codecs) {
    if (codec.EqualsLiteral("opus") || codec.EqualsLiteral("vorbis")) {
      continue;
    }
    // Note: Only accept VP8/VP9 in a video content type, not in an audio
    // content type.
    if (isWebMVideo &&
        (codec.EqualsLiteral("vp8") || codec.EqualsLiteral("vp8.0") ||
         codec.EqualsLiteral("vp9") || codec.EqualsLiteral("vp9.0"))) {

      continue;
    }
    // Some unsupported codec.
    return false;
  }
  return true;
}

/* static */ bool
DecoderTraits::IsWebMAudioType(const nsACString& aType)
{
  return aType.EqualsASCII("audio/webm");
}

/* static */
bool
MP4Decoder::CanHandleMediaType(const nsACString& aMIMETypeExcludingCodecs,
                               const nsAString& aCodecs,
                               DecoderDoctorDiagnostics* aDiagnostics)
{
  if (!IsEnabled()) {
    return false;
  }

  // Whitelist MP4 types, so they explicitly match what we encounter on
  // the web, as opposed to what we use internally (i.e. what our demuxers
  // etc output).
  const bool isMP4Audio = aMIMETypeExcludingCodecs.EqualsASCII("audio/mp4") ||
                          aMIMETypeExcludingCodecs.EqualsASCII("audio/x-m4a") ||
                          aMIMETypeExcludingCodecs.EqualsASCII("audio/opus");
  const bool isMP4Video =
  // On B2G, treat 3GPP as MP4 when Gonk PDM is available.
#ifdef MOZ_GONK_MEDIACODEC
    aMIMETypeExcludingCodecs.EqualsASCII(VIDEO_3GPP) ||
#endif
    aMIMETypeExcludingCodecs.EqualsASCII("video/mp4") ||
    aMIMETypeExcludingCodecs.EqualsASCII("video/quicktime") ||
    aMIMETypeExcludingCodecs.EqualsASCII("video/x-m4v");
  if (!isMP4Audio && !isMP4Video) {
    return false;
  }

  nsTArray<nsCString> codecMimes;
  if (aCodecs.IsEmpty()) {
    // No codecs specified. Assume AAC/H.264
    if (isMP4Audio) {
      codecMimes.AppendElement(NS_LITERAL_CSTRING("audio/mp4a-latm"));
    } else {
      MOZ_ASSERT(isMP4Video);
      codecMimes.AppendElement(NS_LITERAL_CSTRING("video/avc"));
    }
  } else {
    // Verify that all the codecs specified are ones that we expect that
    // we can play.
    nsTArray<nsString> codecs;
    if (!ParseCodecsString(aCodecs, codecs)) {
      return false;
    }
    for (const nsString& codec : codecs) {
      if (IsAACCodecString(codec)) {
        codecMimes.AppendElement(NS_LITERAL_CSTRING("audio/mp4a-latm"));
        continue;
      }
      if (codec.EqualsLiteral("mp3")) {
        codecMimes.AppendElement(NS_LITERAL_CSTRING("audio/mpeg"));
        continue;
      }
      // Note: Only accept H.264 in a video content type, not in an audio
      // content type.
      if (IsWhitelistedH264Codec(codec) && isMP4Video) {
        codecMimes.AppendElement(NS_LITERAL_CSTRING("video/avc"));
        continue;
      }
      // Some unsupported codec.
      return false;
    }
  }

  // Verify that we have a PDM that supports the whitelisted types.
  RefPtr<PDMFactory> platform = new PDMFactory();
  for (const nsCString& codecMime : codecMimes) {
    if (!platform->SupportsMimeType(codecMime, aDiagnostics)) {
      return false;
    }
  }

  return true;
}

 bool Contains(const nsACString& key) const {
   for (int i = 0; i < mLen; ++i)
     if (key.EqualsASCII(mItems[i]))
       return true;
   return false;
 }