Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2011 Google Inc. All Rights Reserved. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| 18 | #define SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |
| 19 | |
| 20 | #include "sfntly/data/font_data.h" |
| 21 | #include "sfntly/port/lock.h" |
| 22 | |
| 23 | namespace sfntly { |
| 24 | |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 25 | class OutputStream; |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 26 | class WritableFontData; |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 27 | |
| 28 | // Writable font data wrapper. Supports reading of data primitives in the |
| 29 | // TrueType / OpenType spec. |
| 30 | // The data types used are as listed: |
| 31 | // BYTE 8-bit unsigned integer. |
| 32 | // CHAR 8-bit signed integer. |
| 33 | // USHORT 16-bit unsigned integer. |
| 34 | // SHORT 16-bit signed integer. |
| 35 | // UINT24 24-bit unsigned integer. |
| 36 | // ULONG 32-bit unsigned integer. |
| 37 | // LONG 32-bit signed integer. |
| 38 | // Fixed 32-bit signed fixed-point number (16.16) |
| 39 | // FUNIT Smallest measurable distance in the em space. |
| 40 | // FWORD 16-bit signed integer (SHORT) that describes a quantity in FUnits. |
| 41 | // UFWORD 16-bit unsigned integer (USHORT) that describes a quantity in |
| 42 | // FUnits. |
| 43 | // F2DOT14 16-bit signed fixed number with the low 14 bits of fraction (2.14) |
| 44 | // LONGDATETIME Date represented in number of seconds since 12:00 midnight, |
| 45 | // January 1, 1904. The value is represented as a signed 64-bit |
| 46 | // integer. |
| 47 | |
| 48 | class ReadableFontData : public FontData, |
| 49 | public RefCounted<ReadableFontData> { |
| 50 | public: |
| 51 | explicit ReadableFontData(ByteArray* array); |
| 52 | virtual ~ReadableFontData(); |
| 53 | |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 54 | static const int32_t kInvalidByte = 128; |
| 55 | static const int32_t kInvalidShort = 32768; |
| 56 | static const int32_t kInvalidLong = 0xffffffff; |
| 57 | static const int32_t kInvalidUnsigned = -1; |
| 58 | static const int64_t kInvalidLongDateTime = -1; |
| 59 | |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 60 | static CALLER_ATTACH ReadableFontData* CreateReadableFontData(ByteVector* b); |
| 61 | |
| 62 | // Gets a computed checksum for the data. This checksum uses the OpenType spec |
| 63 | // calculation. Every ULong value (32 bit unsigned) in the data is summed and |
| 64 | // the resulting value is truncated to 32 bits. If the data length in bytes is |
| 65 | // not an integral multiple of 4 then any remaining bytes are treated as the |
| 66 | // start of a 4 byte sequence whose remaining bytes are zero. |
| 67 | // @return the checksum |
| 68 | int64_t Checksum(); |
| 69 | |
| 70 | // Sets the bounds to use for computing the checksum. These bounds are in |
| 71 | // begin and end pairs. If an odd number is given then the final range is |
| 72 | // assumed to extend to the end of the data. The lengths of each range must be |
| 73 | // a multiple of 4. |
| 74 | // @param ranges the range bounds to use for the checksum |
| 75 | void SetCheckSumRanges(const IntegerList& ranges); |
| 76 | |
| 77 | // Read the UBYTE at the given index. |
| 78 | // @param index index into the font data |
| 79 | // @return the UBYTE; -1 if outside the bounds of the font data |
| 80 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 81 | virtual int32_t ReadUByte(int32_t index); |
| 82 | |
| 83 | // Read the BYTE at the given index. |
| 84 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 85 | // @return the BYTE; |kInvalidByte| if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 86 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 87 | virtual int32_t ReadByte(int32_t index); |
| 88 | |
| 89 | // Read the bytes at the given index into the array. |
| 90 | // @param index index into the font data |
| 91 | // @param b the destination for the bytes read |
| 92 | // @param offset offset in the byte array to place the bytes |
| 93 | // @param length the length of bytes to read |
| 94 | // @return the number of bytes actually read; -1 if the index is outside the |
| 95 | // bounds of the font data |
| 96 | virtual int32_t ReadBytes(int32_t index, |
| 97 | byte_t* b, |
| 98 | int32_t offset, |
| 99 | int32_t length); |
| 100 | |
| 101 | // Read the CHAR at the given index. |
| 102 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 103 | // @return the CHAR; -1 if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 104 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 105 | virtual int32_t ReadChar(int32_t index); |
| 106 | |
| 107 | // Read the USHORT at the given index. |
| 108 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 109 | // @return the USHORT; -1 if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 110 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 111 | virtual int32_t ReadUShort(int32_t index); |
| 112 | |
| 113 | // Read the SHORT at the given index. |
| 114 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 115 | // @return the SHORT; |kInvalidShort| if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 116 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 117 | virtual int32_t ReadShort(int32_t index); |
| 118 | |
| 119 | // Read the UINT24 at the given index. |
| 120 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 121 | // @return the UINT24; -1 if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 122 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 123 | virtual int32_t ReadUInt24(int32_t index); |
| 124 | |
| 125 | // Read the ULONG at the given index. |
| 126 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 127 | // @return the ULONG; kInvalidUnsigned if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 128 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 129 | virtual int64_t ReadULong(int32_t index); |
| 130 | |
| 131 | // Read the ULONG at the given index as int32_t. |
| 132 | // @param index index into the font data |
| 133 | // @return the ULONG |
| 134 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 135 | virtual int32_t ReadULongAsInt(int32_t index); |
| 136 | |
| 137 | // Read the ULONG at the given index, little-endian variant |
| 138 | // @param index index into the font data |
| 139 | // @return the ULONG |
| 140 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 141 | virtual int64_t ReadULongLE(int32_t index); |
| 142 | |
| 143 | // Read the LONG at the given index. |
| 144 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 145 | // @return the LONG; kInvalidLong if outside the bounds of the font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 146 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 147 | virtual int32_t ReadLong(int32_t index); |
| 148 | |
| 149 | // Read the Fixed at the given index. |
| 150 | // @param index index into the font data |
| 151 | // @return the Fixed |
| 152 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 153 | virtual int32_t ReadFixed(int32_t index); |
| 154 | |
| 155 | // Read the LONGDATETIME at the given index. |
| 156 | // @param index index into the font data |
Colin Cross | 13a8243 | 2017-04-07 10:50:33 -0700 | [diff] [blame] | 157 | // @return the LONGDATETIME; kInvalidLongDateTime if outside the bounds of the |
| 158 | // font data |
Selim Gurun | 30d4e1f | 2013-08-15 12:46:15 -0700 | [diff] [blame] | 159 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 160 | virtual int64_t ReadDateTimeAsLong(int32_t index); |
| 161 | |
| 162 | // Read the FWORD at the given index. |
| 163 | // @param index index into the font data |
| 164 | // @return the FWORD |
| 165 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 166 | virtual int32_t ReadFWord(int32_t index); |
| 167 | |
| 168 | // Read the UFWORD at the given index. |
| 169 | // @param index index into the font data |
| 170 | // @return the UFWORD |
| 171 | // @throws IndexOutOfBoundsException if index is outside the FontData's range |
| 172 | virtual int32_t ReadFUFWord(int32_t index); |
| 173 | |
| 174 | // Note: Not ported because they just throw UnsupportedOperationException() |
| 175 | // in Java. |
| 176 | /* |
| 177 | virtual int32_t ReadFUnit(int32_t index); |
| 178 | virtual int64_t ReadF2Dot14(int32_t index); |
| 179 | */ |
| 180 | |
| 181 | // Copy the FontData to an OutputStream. |
| 182 | // @param os the destination |
| 183 | // @return number of bytes copied |
| 184 | // @throws IOException |
| 185 | virtual int32_t CopyTo(OutputStream* os); |
| 186 | |
| 187 | // Copy the FontData to a WritableFontData. |
| 188 | // @param wfd the destination |
| 189 | // @return number of bytes copied |
| 190 | // @throws IOException |
| 191 | virtual int32_t CopyTo(WritableFontData* wfd); |
| 192 | |
| 193 | // Make gcc -Woverloaded-virtual happy. |
| 194 | virtual int32_t CopyTo(ByteArray* ba); |
| 195 | |
| 196 | // Search for the key value in the range tables provided. |
| 197 | // The search looks through the start-end pairs looking for the key value. It |
| 198 | // is assumed that the start-end pairs are both represented by UShort values, |
| 199 | // ranges do not overlap, and are monotonically increasing. |
| 200 | // @param startIndex the position to read the first start value from |
| 201 | // @param startOffset the offset between subsequent start values |
| 202 | // @param endIndex the position to read the first end value from |
| 203 | // @param endOffset the offset between subsequent end values |
| 204 | // @param length the number of start-end pairs |
| 205 | // @param key the value to search for |
| 206 | // @return the index of the start-end pairs in which the key was found; -1 |
| 207 | // otherwise |
| 208 | int32_t SearchUShort(int32_t start_index, |
| 209 | int32_t start_offset, |
| 210 | int32_t end_index, |
| 211 | int32_t end_offset, |
| 212 | int32_t length, |
| 213 | int32_t key); |
| 214 | |
| 215 | // Search for the key value in the table provided. |
| 216 | // The search looks through the values looking for the key value. It is |
| 217 | // assumed that the are represented by UShort values and are monotonically |
| 218 | // increasing. |
| 219 | // @param startIndex the position to read the first start value from |
| 220 | // @param startOffset the offset between subsequent start values |
| 221 | // @param length the number of start-end pairs |
| 222 | // @param key the value to search for |
| 223 | // @return the index of the start-end pairs in which the key was found; -1 |
| 224 | // otherwise |
| 225 | int32_t SearchUShort(int32_t start_index, |
| 226 | int32_t start_offset, |
| 227 | int32_t length, |
| 228 | int32_t key); |
| 229 | |
| 230 | // Search for the key value in the range tables provided. |
| 231 | // The search looks through the start-end pairs looking for the key value. It |
| 232 | // is assumed that the start-end pairs are both represented by ULong values |
| 233 | // that can be represented within 31 bits, ranges do not overlap, and are |
| 234 | // monotonically increasing. |
| 235 | // @param startIndex the position to read the first start value from |
| 236 | // @param startOffset the offset between subsequent start values |
| 237 | // @param endIndex the position to read the first end value from |
| 238 | // @param endOffset the offset between subsequent end values |
| 239 | // @param length the number of start-end pairs |
| 240 | // @param key the value to search for |
| 241 | // @return the index of the start-end pairs in which the key was found; -1 |
| 242 | // otherwise |
| 243 | int32_t SearchULong(int32_t start_index, |
| 244 | int32_t start_offset, |
| 245 | int32_t end_index, |
| 246 | int32_t end_offset, |
| 247 | int32_t length, |
| 248 | int32_t key); |
| 249 | |
| 250 | |
| 251 | // TODO(arthurhsu): IMPLEMENT |
| 252 | /* |
| 253 | virtual int32_t ReadFUnit(int32_t index); |
| 254 | virtual int64_t ReadF2Dot14(int32_t index); |
| 255 | virtual int64_t ReadLongDateTime(int32_t index); |
| 256 | */ |
| 257 | |
| 258 | // Makes a slice of this FontData. The returned slice will share the data with |
| 259 | // the original FontData. |
| 260 | // @param offset the start of the slice |
| 261 | // @param length the number of bytes in the slice |
| 262 | // @return a slice of the original FontData |
| 263 | // Note: C++ polymorphism requires return type to be consistent |
| 264 | virtual CALLER_ATTACH FontData* Slice(int32_t offset, int32_t length); |
| 265 | |
| 266 | // Makes a bottom bound only slice of this array. The returned slice will |
| 267 | // share the data with the original FontData. |
| 268 | // @param offset the start of the slice |
| 269 | // @return a slice of the original FontData |
| 270 | // Note: C++ polymorphism requires return type to be consistent |
| 271 | virtual CALLER_ATTACH FontData* Slice(int32_t offset); |
| 272 | |
| 273 | // Not Ported: toString() |
| 274 | |
| 275 | protected: |
| 276 | // Constructor. Creates a bounded wrapper of another ReadableFontData from the |
| 277 | // given offset until the end of the original ReadableFontData. |
| 278 | // @param data data to wrap |
| 279 | // @param offset the start of this data's view of the original data |
| 280 | ReadableFontData(ReadableFontData* data, int32_t offset); |
| 281 | |
| 282 | // Constructor. Creates a bounded wrapper of another ReadableFontData from the |
| 283 | // given offset until the end of the original ReadableFontData. |
| 284 | // @param data data to wrap |
| 285 | // @param offset the start of this data's view of the original data |
| 286 | // @param length the length of the other FontData to use |
| 287 | ReadableFontData(ReadableFontData* data, int32_t offset, int32_t length); |
| 288 | |
| 289 | private: |
| 290 | // Compute the checksum for the font data using any ranges set for the |
| 291 | // calculation. |
| 292 | void ComputeChecksum(); |
| 293 | |
| 294 | // Do the actual computation of the checksum for a range using the |
| 295 | // TrueType/OpenType checksum algorithm. The range used is from the low bound |
| 296 | // to the high bound in steps of four bytes. If any of the bytes within that 4 |
| 297 | // byte segment are not readable then it will considered a zero for |
| 298 | // calculation. |
| 299 | // Only called from within a synchronized method so it does not need to be |
| 300 | // synchronized itself. |
| 301 | // @param lowBound first position to start a 4 byte segment on |
| 302 | // @param highBound last possible position to start a 4 byte segment on |
| 303 | // @return the checksum for the total range |
| 304 | int64_t ComputeCheckSum(int32_t low_bound, int32_t high_bound); |
| 305 | |
| 306 | Lock checksum_lock_; |
| 307 | bool checksum_set_; |
| 308 | int64_t checksum_; |
| 309 | IntegerList checksum_range_; |
| 310 | }; |
| 311 | typedef Ptr<ReadableFontData> ReadableFontDataPtr; |
| 312 | |
| 313 | } // namespace sfntly |
| 314 | |
| 315 | #endif // SFNTLY_CPP_SRC_SFNTLY_DATA_READABLE_FONT_DATA_H_ |