michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef MOZILLA_IMAGELIB_EXIF_H_
michael@0: #define MOZILLA_IMAGELIB_EXIF_H_
michael@0: 
michael@0: #include <stdint.h>
michael@0: #include "mozilla/TypedEnum.h"
michael@0: #include "nsDebug.h"
michael@0: 
michael@0: #include "Orientation.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace image {
michael@0: 
michael@0: MOZ_BEGIN_ENUM_CLASS(ByteOrder, uint8_t)
michael@0:   Unknown,
michael@0:   LittleEndian,
michael@0:   BigEndian
michael@0: MOZ_END_ENUM_CLASS(ByteOrder)
michael@0: 
michael@0: struct EXIFData
michael@0: {
michael@0:   EXIFData() { }
michael@0:   explicit EXIFData(Orientation aOrientation) : orientation(aOrientation) { }
michael@0: 
michael@0:   const Orientation orientation;
michael@0: };
michael@0: 
michael@0: class EXIFParser
michael@0: {
michael@0: public:
michael@0:   static EXIFData
michael@0:   Parse(const uint8_t* aData, const uint32_t aLength)
michael@0:   {
michael@0:     EXIFParser parser;
michael@0:     return parser.ParseEXIF(aData, aLength);
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   EXIFParser()
michael@0:     : mStart(nullptr)
michael@0:     , mCurrent(nullptr)
michael@0:     , mLength(0)
michael@0:     , mRemainingLength(0)
michael@0:     , mByteOrder(ByteOrder::Unknown)
michael@0:   { }
michael@0: 
michael@0:   EXIFData ParseEXIF(const uint8_t* aData, const uint32_t aLength);
michael@0:   bool ParseEXIFHeader();
michael@0:   bool ParseTIFFHeader(uint32_t& aIFD0OffsetOut);
michael@0:   bool ParseIFD0(Orientation& aOrientationOut);
michael@0:   bool ParseOrientation(uint16_t aType, uint32_t aCount, Orientation& aOut);
michael@0: 
michael@0:   bool Initialize(const uint8_t* aData, const uint32_t aLength);
michael@0:   void Advance(const uint32_t aDistance);
michael@0:   void JumpTo(const uint32_t aOffset);
michael@0: 
michael@0:   bool MatchString(const char* aString, const uint32_t aLength);
michael@0:   bool MatchUInt16(const uint16_t aValue);
michael@0:   bool ReadUInt16(uint16_t& aOut);
michael@0:   bool ReadUInt32(uint32_t& aOut);
michael@0: 
michael@0:   const uint8_t* mStart;
michael@0:   const uint8_t* mCurrent;
michael@0:   uint32_t       mLength;
michael@0:   uint32_t       mRemainingLength;
michael@0:   ByteOrder      mByteOrder;
michael@0: };
michael@0: 
michael@0: }
michael@0: }
michael@0: 
michael@0: #endif