| /* |
| * 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 SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| #define SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| |
| #include "sfntly/data/font_data.h" |
| #include "sfntly/port/lock.h" |
| |
| namespace sfntly { |
| |
| class OutputStream; |
| class WritableFontData; |
| |
| // Writable font data wrapper. Supports reading of data primitives in the |
| // TrueType / OpenType spec. |
| // The data types used are as listed: |
| // BYTE 8-bit unsigned integer. |
| // CHAR 8-bit signed integer. |
| // USHORT 16-bit unsigned integer. |
| // SHORT 16-bit signed integer. |
| // UINT24 24-bit unsigned integer. |
| // ULONG 32-bit unsigned integer. |
| // LONG 32-bit signed integer. |
| // Fixed 32-bit signed fixed-point number (16.16) |
| // FUNIT Smallest measurable distance in the em space. |
| // FWORD 16-bit signed integer (SHORT) that describes a quantity in FUnits. |
| // UFWORD 16-bit unsigned integer (USHORT) that describes a quantity in |
| // FUnits. |
| // F2DOT14 16-bit signed fixed number with the low 14 bits of fraction (2.14) |
| // LONGDATETIME Date represented in number of seconds since 12:00 midnight, |
| // January 1, 1904. The value is represented as a signed 64-bit |
| // integer. |
| |
| class ReadableFontData : public FontData, |
| public RefCounted<ReadableFontData> { |
| public: |
| explicit ReadableFontData(ByteArray* array); |
| virtual ~ReadableFontData(); |
| |
| static const int32_t kInvalidByte = 128; |
| static const int32_t kInvalidShort = 32768; |
| static const int32_t kInvalidLong = 0xffffffff; |
| static const int32_t kInvalidUnsigned = -1; |
| static const int64_t kInvalidLongDateTime = -1; |
| |
| static CALLER_ATTACH ReadableFontData* CreateReadableFontData(ByteVector* b); |
| |
| // Gets 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); |
| |
| // Read the UBYTE at the given index. |
| // @param index index into the font data |
| // @return the UBYTE; -1 if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadUByte(int32_t index); |
| |
| // Read the BYTE at the given index. |
| // @param index index into the font data |
| // @return the BYTE; |kInvalidByte| if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadByte(int32_t index); |
| |
| // Read the bytes at the given index into the array. |
| // @param index index into the font data |
| // @param b the destination for the bytes read |
| // @param offset offset in the byte array to place the bytes |
| // @param length the length of bytes to read |
| // @return the number of bytes actually read; -1 if the index is outside the |
| // bounds of the font data |
| virtual int32_t ReadBytes(int32_t index, |
| byte_t* b, |
| int32_t offset, |
| int32_t length); |
| |
| // Read the CHAR at the given index. |
| // @param index index into the font data |
| // @return the CHAR; -1 if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadChar(int32_t index); |
| |
| // Read the USHORT at the given index. |
| // @param index index into the font data |
| // @return the USHORT; -1 if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadUShort(int32_t index); |
| |
| // Read the SHORT at the given index. |
| // @param index index into the font data |
| // @return the SHORT; |kInvalidShort| if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadShort(int32_t index); |
| |
| // Read the UINT24 at the given index. |
| // @param index index into the font data |
| // @return the UINT24; -1 if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadUInt24(int32_t index); |
| |
| // Read the ULONG at the given index. |
| // @param index index into the font data |
| // @return the ULONG; kInvalidUnsigned if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int64_t ReadULong(int32_t index); |
| |
| // Read the ULONG at the given index as int32_t. |
| // @param index index into the font data |
| // @return the ULONG |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadULongAsInt(int32_t index); |
| |
| // Read the ULONG at the given index, little-endian variant |
| // @param index index into the font data |
| // @return the ULONG |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int64_t ReadULongLE(int32_t index); |
| |
| // Read the LONG at the given index. |
| // @param index index into the font data |
| // @return the LONG; kInvalidLong if outside the bounds of the font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadLong(int32_t index); |
| |
| // Read the Fixed at the given index. |
| // @param index index into the font data |
| // @return the Fixed |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadFixed(int32_t index); |
| |
| // Read the LONGDATETIME at the given index. |
| // @param index index into the font data |
| // @return the LONGDATETIME; kInvalidLongDateTime if outside the bounds of the |
| // font data |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int64_t ReadDateTimeAsLong(int32_t index); |
| |
| // Read the FWORD at the given index. |
| // @param index index into the font data |
| // @return the FWORD |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadFWord(int32_t index); |
| |
| // Read the UFWORD at the given index. |
| // @param index index into the font data |
| // @return the UFWORD |
| // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| virtual int32_t ReadFUFWord(int32_t index); |
| |
| // Note: Not ported because they just throw UnsupportedOperationException() |
| // in Java. |
| /* |
| virtual int32_t ReadFUnit(int32_t index); |
| virtual int64_t ReadF2Dot14(int32_t index); |
| */ |
| |
| // Copy the FontData to an OutputStream. |
| // @param os the destination |
| // @return number of bytes copied |
| // @throws IOException |
| virtual int32_t CopyTo(OutputStream* os); |
| |
| // Copy the FontData to a WritableFontData. |
| // @param wfd the destination |
| // @return number of bytes copied |
| // @throws IOException |
| virtual int32_t CopyTo(WritableFontData* wfd); |
| |
| // Make gcc -Woverloaded-virtual happy. |
| virtual int32_t CopyTo(ByteArray* ba); |
| |
| // Search for the key value in the range tables provided. |
| // The search looks through the start-end pairs looking for the key value. It |
| // is assumed that the start-end pairs are both represented by UShort values, |
| // ranges do not overlap, and are monotonically increasing. |
| // @param startIndex the position to read the first start value from |
| // @param startOffset the offset between subsequent start values |
| // @param endIndex the position to read the first end value from |
| // @param endOffset the offset between subsequent end values |
| // @param length the number of start-end pairs |
| // @param key the value to search for |
| // @return the index of the start-end pairs in which the key was found; -1 |
| // otherwise |
| int32_t SearchUShort(int32_t start_index, |
| int32_t start_offset, |
| int32_t end_index, |
| int32_t end_offset, |
| int32_t length, |
| int32_t key); |
| |
| // Search for the key value in the table provided. |
| // The search looks through the values looking for the key value. It is |
| // assumed that the are represented by UShort values and are monotonically |
| // increasing. |
| // @param startIndex the position to read the first start value from |
| // @param startOffset the offset between subsequent start values |
| // @param length the number of start-end pairs |
| // @param key the value to search for |
| // @return the index of the start-end pairs in which the key was found; -1 |
| // otherwise |
| int32_t SearchUShort(int32_t start_index, |
| int32_t start_offset, |
| int32_t length, |
| int32_t key); |
| |
| // Search for the key value in the range tables provided. |
| // The search looks through the start-end pairs looking for the key value. It |
| // is assumed that the start-end pairs are both represented by ULong values |
| // that can be represented within 31 bits, ranges do not overlap, and are |
| // monotonically increasing. |
| // @param startIndex the position to read the first start value from |
| // @param startOffset the offset between subsequent start values |
| // @param endIndex the position to read the first end value from |
| // @param endOffset the offset between subsequent end values |
| // @param length the number of start-end pairs |
| // @param key the value to search for |
| // @return the index of the start-end pairs in which the key was found; -1 |
| // otherwise |
| 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); |
| |
| |
| // TODO(arthurhsu): IMPLEMENT |
| /* |
| virtual int32_t ReadFUnit(int32_t index); |
| virtual int64_t ReadF2Dot14(int32_t index); |
| virtual int64_t ReadLongDateTime(int32_t index); |
| */ |
| |
| // 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 |
| // Note: C++ polymorphism requires return type to be consistent |
| 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 |
| // Note: C++ polymorphism requires return type to be consistent |
| virtual CALLER_ATTACH FontData* Slice(int32_t offset); |
| |
| // Not Ported: toString() |
| |
| 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 |
| // @param length the length of the other FontData to use |
| ReadableFontData(ReadableFontData* data, int32_t offset, int32_t length); |
| |
| private: |
| // Compute the checksum for the font data using any ranges set for the |
| // calculation. |
| void ComputeChecksum(); |
| |
| // Do the actual computation of the checksum for a range using the |
| // TrueType/OpenType checksum algorithm. The range used is from the low bound |
| // to the high bound in steps of four bytes. If any of the bytes within that 4 |
| // byte segment are not readable then it will considered a zero for |
| // calculation. |
| // Only called from within a synchronized method so it does not need to be |
| // synchronized itself. |
| // @param lowBound first position to start a 4 byte segment on |
| // @param highBound last possible position to start a 4 byte segment on |
| // @return the checksum for the total range |
| int64_t ComputeCheckSum(int32_t low_bound, int32_t high_bound); |
| |
| Lock checksum_lock_; |
| bool checksum_set_; |
| int64_t checksum_; |
| IntegerList checksum_range_; |
| }; |
| typedef Ptr<ReadableFontData> ReadableFontDataPtr; |
| |
| } // namespace sfntly |
| |
| #endif // SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |