| /* |
| * Copyright 2011 Google Inc. All Rights Reserved. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef TYPOGRAPHY_FONT_SFNTLY_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| #define TYPOGRAPHY_FONT_SFNTLY_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| |
| #include "sfntly/port/refcount.h" |
| #include "sfntly/data/font_data.h" |
| |
| namespace sfntly { |
| |
| class WritableFontData; |
| class OutputStream; |
| class ReadableFontData : public FontData, |
| public RefCounted<ReadableFontData> { |
| public: |
| explicit ReadableFontData(ByteArray* array); |
| virtual ~ReadableFontData(); |
| |
| // Get a computed checksum for the data. This checksum uses the OpenType spec |
| // calculation. Every ULong value (32 bit unsigned) in the data is summed and |
| // the resulting value is truncated to 32 bits. If the data length in bytes is |
| // not an integral multiple of 4 then any remaining bytes are treated as the |
| // start of a 4 byte sequence whose remaining bytes are zero. |
| // @return the checksum |
| int64_t Checksum(); |
| |
| // Sets the bounds to use for computing the checksum. These bounds are in |
| // begin and end pairs. If an odd number is given then the final range is |
| // assumed to extend to the end of the data. The lengths of each range must be |
| // a multiple of 4. |
| // @param ranges the range bounds to use for the checksum |
| void SetCheckSumRanges(const IntegerList& ranges); |
| |
| virtual int32_t ReadUByte(int32_t index); |
| virtual int32_t ReadByte(int32_t index); |
| virtual int32_t ReadBytes(int32_t index, ByteVector* b, int32_t offset, |
| int32_t length); |
| virtual int32_t ReadChar(int32_t index); |
| virtual int32_t ReadUShort(int32_t index); |
| virtual int32_t ReadShort(int32_t index); |
| virtual int32_t ReadUInt24(int32_t index); |
| virtual int64_t ReadULong(int32_t index); |
| virtual int32_t ReadULongAsInt(int32_t index); |
| virtual int32_t ReadLong(int32_t index); |
| virtual int32_t ReadFixed(int32_t index); |
| virtual int64_t ReadDateTimeAsLong(int32_t index); |
| |
| virtual int32_t ReadFWord(int32_t index); |
| virtual int32_t ReadFUFWord(int32_t index); |
| |
| virtual int32_t CopyTo(OutputStream* os); |
| virtual int32_t CopyTo(WritableFontData* wfd); |
| virtual int32_t CopyTo(ByteArray* ba); |
| |
| // TODO(arthurhsu): IMPLEMENT |
| /* |
| virtual int32_t ReadFUnit(int32_t index); |
| virtual int64_t ReadF2Dot14(int32_t index); |
| virtual int64_t ReadLongDateTime(int32_t index); |
| virtual int32_t SearchUShort(int32_t start, int32_t length, int32_t key); |
| virtual int32_t SearchUShort(int32_t start_index, int32_t start_offset, |
| int32_t count_index, int32_t count_offset, |
| int32_t length, int32_t key); |
| virtual int32_t SearchULong(int32_t start_index, int32_t start_offset, |
| int32_t end_index, int32_t end_offset, |
| int32_t length, int32_t key); |
| */ |
| |
| // Makes a slice of this FontData. The returned slice will share the data with |
| // the original FontData. |
| // @param offset the start of the slice |
| // @param length the number of bytes in the slice |
| // @return a slice of the original FontData |
| virtual CALLER_ATTACH FontData* Slice(int32_t offset, int32_t length); |
| |
| // Makes a bottom bound only slice of this array. The returned slice will |
| // share the data with the original FontData. |
| // @param offset the start of the slice |
| // @return a slice of the original FontData |
| virtual CALLER_ATTACH FontData* Slice(int32_t offset); |
| |
| protected: |
| // Constructor. Creates a bounded wrapper of another ReadableFontData from the |
| // given offset until the end of the original ReadableFontData. |
| // @param data data to wrap |
| // @param offset the start of this data's view of the original data |
| ReadableFontData(ReadableFontData* data, int32_t offset); |
| |
| // Constructor. Creates a bounded wrapper of another ReadableFontData from the |
| // given offset until the end of the original ReadableFontData. |
| // @param data data to wrap |
| // @param offset the start of this data's view of the original data |
| ReadableFontData(ReadableFontData* data, int32_t offset, int32_t length); |
| |
| private: |
| void ComputeChecksum(); |
| int64_t ComputeCheckSum(int32_t low_bound, int32_t high_bound); |
| |
| bool checksum_set_; // TODO(arthurhsu): IMPLEMENT: must be set atomically. |
| int64_t checksum_; |
| IntegerList checksum_range_; |
| }; |
| typedef Ptr<ReadableFontData> ReadableFontDataPtr; |
| |
| } // namespace sfntly |
| |
| #endif // TYPOGRAPHY_FONT_SFNTLY_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |