gecko-dev/dom/media/MediaMIMETypes.h

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/* -*- 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/. */
#ifndef MediaMIMETypes_h_
#define MediaMIMETypes_h_
#include "VideoUtils.h"
#include "mozilla/Maybe.h"
#include "nsString.h"
namespace mozilla {
namespace dom {
struct AudioConfiguration;
struct VideoConfiguration;
} // namespace dom
// Class containing pointing at a media MIME "type/subtype" string literal.
// See IsMediaMIMEType for restrictions.
// Mainly used to help construct a MediaMIMEType through the statically-checked
// MEDIAMIMETYPE macro, or to compare a MediaMIMEType to a literal.
class DependentMediaMIMEType {
public:
// Construction from a literal. Checked in debug builds.
// Use MEDIAMIMETYPE macro instead, for static checking.
template <size_t N>
explicit DependentMediaMIMEType(const char (&aType)[N])
: mMIMEType(aType, N - 1) {
MOZ_ASSERT(IsMediaMIMEType(aType, N - 1), "Invalid media MIME type");
}
// MIME "type/subtype".
const nsDependentCString& AsDependentString() const { return mMIMEType; }
private:
nsDependentCString mMIMEType;
};
// Instantiate a DependentMediaMIMEType from a literal. Statically checked.
#define MEDIAMIMETYPE(LIT) \
static_cast<const DependentMediaMIMEType&>([]() { \
static_assert(IsMediaMIMEType(LIT), "Invalid media MIME type"); \
return DependentMediaMIMEType(LIT); \
}())
// Class containing only pre-parsed lowercase media MIME type/subtype.
class MediaMIMEType {
public:
// Construction from a DependentMediaMIMEType, with its inherent checks.
// Implicit so MEDIAMIMETYPE can be used wherever a MediaMIMEType is expected.
MOZ_IMPLICIT MediaMIMEType(const DependentMediaMIMEType& aType)
: mMIMEType(aType.AsDependentString()) {}
// MIME "type/subtype", always lowercase.
const nsCString& AsString() const { return mMIMEType; }
// Comparison with DependentMediaMIMEType.
// Useful to compare to MEDIAMIMETYPE literals.
bool operator==(const DependentMediaMIMEType& aOther) const {
return mMIMEType.Equals(aOther.AsDependentString());
}
bool operator!=(const DependentMediaMIMEType& aOther) const {
return !mMIMEType.Equals(aOther.AsDependentString());
}
bool operator==(const MediaMIMEType& aOther) const {
return mMIMEType.Equals(aOther.mMIMEType);
}
bool operator!=(const MediaMIMEType& aOther) const {
return !mMIMEType.Equals(aOther.mMIMEType);
}
// True if type starts with "application/".
bool HasApplicationMajorType() const;
// True if type starts with "audio/".
// Note that some audio content could be stored in a "video/..." container!
bool HasAudioMajorType() const;
// True if type starts with "video/".
// Note that this does not guarantee 100% that the content is actually video!
// (e.g., "video/webm" could contain a vorbis audio track.)
bool HasVideoMajorType() const;
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
private:
friend Maybe<MediaMIMEType> MakeMediaMIMEType(const nsAString& aType);
friend class MediaExtendedMIMEType;
explicit MediaMIMEType(const nsACString& aType);
nsCString mMIMEType; // UTF8 MIME "type/subtype".
};
Maybe<MediaMIMEType> MakeMediaMIMEType(const nsAString& aType);
Maybe<MediaMIMEType> MakeMediaMIMEType(const nsACString& aType);
Maybe<MediaMIMEType> MakeMediaMIMEType(const char* aType);
// A list of case-sensitive codecs attached to a MediaExtendedMIMEType.
class MediaCodecs {
public:
MediaCodecs() {}
// Construction from a comma-separated list of codecs. Unchecked.
explicit MediaCodecs(const nsAString& aCodecs) : mCodecs(aCodecs) {}
// Construction from a literal comma-separated list of codecs. Unchecked.
template <size_t N>
explicit MediaCodecs(const char (&aCodecs)[N])
: mCodecs(NS_ConvertUTF8toUTF16(aCodecs, N - 1)) {}
bool IsEmpty() const { return mCodecs.IsEmpty(); }
const nsString& AsString() const { return mCodecs; }
using RangeType =
const StringListRange<nsString,
StringListRangeEmptyItems::ProcessEmptyItems>;
// Produces a range object with begin()&end(), can be used in range-for loops.
// This will iterate through all codecs, even empty ones (except if the
// original list was an empty string). Iterators dereference to
// 'const nsDependentString', valid for as long as this MediaCodecs object.
RangeType Range() const { return RangeType(mCodecs); };
// Does this list of codecs contain the given aCodec?
bool Contains(const nsAString& aCodec) const;
// Does this list of codecs contain *all* the codecs in the given list?
bool ContainsAll(const MediaCodecs& aCodecs) const;
// Does this list of codecs contain a codec starting with the given prefix?
bool ContainsPrefix(const nsAString& aCodecPrefix) const;
template <size_t N>
bool operator==(const char (&aType)[N]) const {
return mCodecs.EqualsASCII(aType, N - 1);
}
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
private:
// UTF16 comma-separated list of codecs.
// See http://www.rfc-editor.org/rfc/rfc4281.txt for the description
// of the 'codecs' parameter.
nsString mCodecs;
};
// Class containing pre-parsed media MIME type parameters, e.g.:
// MIME type/subtype, optional codecs, etc.
class MediaExtendedMIMEType {
public:
explicit MediaExtendedMIMEType(const MediaMIMEType& aType);
explicit MediaExtendedMIMEType(MediaMIMEType&& aType);
// MIME "type/subtype".
const MediaMIMEType& Type() const { return mMIMEType; }
// Was there an explicit 'codecs' parameter provided?
bool HaveCodecs() const { return mHaveCodecs; }
// Codecs. May be empty if not provided or explicitly provided as empty.
const MediaCodecs& Codecs() const { return mCodecs; }
// Sizes and rates.
Maybe<int32_t> GetWidth() const { return GetMaybeNumber(mWidth); }
Maybe<int32_t> GetHeight() const { return GetMaybeNumber(mHeight); }
Maybe<double> GetFramerate() const { return GetMaybeNumber(mFramerate); }
Maybe<int32_t> GetBitrate() const { return GetMaybeNumber(mBitrate); }
Maybe<int32_t> GetChannels() const { return GetMaybeNumber(mChannels); }
Maybe<int32_t> GetSamplerate() const { return GetMaybeNumber(mSamplerate); }
// Original string. Note that "type/subtype" may not be lowercase,
// use Type().AsString() instead to get the normalized "type/subtype".
const nsCString& OriginalString() const { return mOriginalString; }
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
// aFrac is either a floating-point number or a fraction made of two
// floating-point numbers.
static Maybe<double> ComputeFractionalString(const nsAString& aFrac);
private:
friend Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(
const nsAString& aType);
friend Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(
const dom::VideoConfiguration& aConfig);
friend Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(
const dom::AudioConfiguration& aConfig);
MediaExtendedMIMEType(const nsACString& aOriginalString,
const nsACString& aMIMEType, bool aHaveCodecs,
const nsAString& aCodecs, int32_t aWidth,
int32_t aHeight, double aFramerate, int32_t aBitrate);
MediaExtendedMIMEType(const nsACString& aOriginalString,
const nsACString& aMIMEType, bool aHaveCodecs,
const nsAString& aCodecs, int32_t aChannels,
int32_t aSamplerate, int32_t aBitrate);
template <typename T>
Maybe<T> GetMaybeNumber(T aNumber) const {
return (aNumber < 0) ? Maybe<T>(Nothing()) : Some(T(aNumber));
}
nsCString mOriginalString; // Original full string.
MediaMIMEType mMIMEType; // MIME type/subtype.
bool mHaveCodecs = false; // If false, mCodecs must be empty.
MediaCodecs mCodecs;
// For video
int32_t mWidth = -1; // -1 if not provided.
int32_t mHeight = -1; // -1 if not provided.
double mFramerate = -1; // -1 if not provided.
// For audio
int32_t mChannels = -1; // -1 if not provided.
int32_t mSamplerate = -1; // -1 if not provided.
// For both audio and video.
int32_t mBitrate = -1; // -1 if not provided.
};
Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(const nsAString& aType);
Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(const nsACString& aType);
Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(const char* aType);
Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(
const dom::VideoConfiguration& aConfig);
Maybe<MediaExtendedMIMEType> MakeMediaExtendedMIMEType(
const dom::AudioConfiguration& aConfig);
} // namespace mozilla
#endif // MediaMIMETypes_h_