Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 1 | // Copyright 2014 Google Inc. All Rights Reserved. |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | // |
Kenichi Ishibashi | c75ed76 | 2014-06-04 08:29:53 +0900 | [diff] [blame^] | 15 | // Library for converting WOFF2 format font files to their TTF versions. |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 16 | |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 17 | #include "./woff2_dec.h" |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 18 | |
| 19 | #include <stdlib.h> |
| 20 | #include <complex> |
| 21 | #include <cstring> |
| 22 | #include <limits> |
| 23 | #include <string> |
| 24 | #include <vector> |
| 25 | |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 26 | #include "./buffer.h" |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 27 | #include "./decode.h" |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 28 | #include "./round.h" |
| 29 | #include "./store_bytes.h" |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 30 | #include "./table_tags.h" |
| 31 | #include "./woff2_common.h" |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 32 | |
| 33 | namespace woff2 { |
| 34 | |
| 35 | namespace { |
| 36 | |
| 37 | using std::string; |
| 38 | using std::vector; |
| 39 | |
| 40 | |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 41 | // simple glyph flags |
| 42 | const int kGlyfOnCurve = 1 << 0; |
| 43 | const int kGlyfXShort = 1 << 1; |
| 44 | const int kGlyfYShort = 1 << 2; |
| 45 | const int kGlyfRepeat = 1 << 3; |
| 46 | const int kGlyfThisXIsSame = 1 << 4; |
| 47 | const int kGlyfThisYIsSame = 1 << 5; |
| 48 | |
| 49 | // composite glyph flags |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 50 | // See CompositeGlyph.java in sfntly for full definitions |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 51 | const int FLAG_ARG_1_AND_2_ARE_WORDS = 1 << 0; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 52 | const int FLAG_WE_HAVE_A_SCALE = 1 << 3; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 53 | const int FLAG_MORE_COMPONENTS = 1 << 5; |
| 54 | const int FLAG_WE_HAVE_AN_X_AND_Y_SCALE = 1 << 6; |
| 55 | const int FLAG_WE_HAVE_A_TWO_BY_TWO = 1 << 7; |
| 56 | const int FLAG_WE_HAVE_INSTRUCTIONS = 1 << 8; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 57 | |
| 58 | const size_t kSfntHeaderSize = 12; |
| 59 | const size_t kSfntEntrySize = 16; |
| 60 | const size_t kCheckSumAdjustmentOffset = 8; |
| 61 | |
| 62 | const size_t kEndPtsOfContoursOffset = 10; |
| 63 | const size_t kCompositeGlyphBegin = 10; |
| 64 | |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 65 | // Based on section 6.1.1 of MicroType Express draft spec |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 66 | bool Read255UShort(Buffer* buf, unsigned int* value) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 67 | static const int kWordCode = 253; |
| 68 | static const int kOneMoreByteCode2 = 254; |
| 69 | static const int kOneMoreByteCode1 = 255; |
| 70 | static const int kLowestUCode = 253; |
| 71 | uint8_t code = 0; |
| 72 | if (!buf->ReadU8(&code)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 73 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 74 | } |
| 75 | if (code == kWordCode) { |
| 76 | uint16_t result = 0; |
| 77 | if (!buf->ReadU16(&result)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 78 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 79 | } |
| 80 | *value = result; |
| 81 | return true; |
| 82 | } else if (code == kOneMoreByteCode1) { |
| 83 | uint8_t result = 0; |
| 84 | if (!buf->ReadU8(&result)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 85 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 86 | } |
| 87 | *value = result + kLowestUCode; |
| 88 | return true; |
| 89 | } else if (code == kOneMoreByteCode2) { |
| 90 | uint8_t result = 0; |
| 91 | if (!buf->ReadU8(&result)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 92 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 93 | } |
| 94 | *value = result + kLowestUCode * 2; |
| 95 | return true; |
| 96 | } else { |
| 97 | *value = code; |
| 98 | return true; |
| 99 | } |
| 100 | } |
| 101 | |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 102 | bool ReadBase128(Buffer* buf, uint32_t* value) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 103 | uint32_t result = 0; |
| 104 | for (size_t i = 0; i < 5; ++i) { |
| 105 | uint8_t code = 0; |
| 106 | if (!buf->ReadU8(&code)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 107 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 108 | } |
| 109 | // If any of the top seven bits are set then we're about to overflow. |
| 110 | if (result & 0xe0000000) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 111 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 112 | } |
| 113 | result = (result << 7) | (code & 0x7f); |
| 114 | if ((code & 0x80) == 0) { |
| 115 | *value = result; |
| 116 | return true; |
| 117 | } |
| 118 | } |
| 119 | // Make sure not to exceed the size bound |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 120 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 121 | } |
| 122 | |
| 123 | int WithSign(int flag, int baseval) { |
| 124 | // Precondition: 0 <= baseval < 65536 (to avoid integer overflow) |
| 125 | return (flag & 1) ? baseval : -baseval; |
| 126 | } |
| 127 | |
| 128 | bool TripletDecode(const uint8_t* flags_in, const uint8_t* in, size_t in_size, |
| 129 | unsigned int n_points, std::vector<Point>* result, |
| 130 | size_t* in_bytes_consumed) { |
| 131 | int x = 0; |
| 132 | int y = 0; |
| 133 | |
| 134 | if (n_points > in_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 135 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 136 | } |
| 137 | unsigned int triplet_index = 0; |
| 138 | |
| 139 | for (unsigned int i = 0; i < n_points; ++i) { |
| 140 | uint8_t flag = flags_in[i]; |
| 141 | bool on_curve = !(flag >> 7); |
| 142 | flag &= 0x7f; |
| 143 | unsigned int n_data_bytes; |
| 144 | if (flag < 84) { |
| 145 | n_data_bytes = 1; |
| 146 | } else if (flag < 120) { |
| 147 | n_data_bytes = 2; |
| 148 | } else if (flag < 124) { |
| 149 | n_data_bytes = 3; |
| 150 | } else { |
| 151 | n_data_bytes = 4; |
| 152 | } |
| 153 | if (triplet_index + n_data_bytes > in_size || |
| 154 | triplet_index + n_data_bytes < triplet_index) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 155 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 156 | } |
| 157 | int dx, dy; |
| 158 | if (flag < 10) { |
| 159 | dx = 0; |
| 160 | dy = WithSign(flag, ((flag & 14) << 7) + in[triplet_index]); |
| 161 | } else if (flag < 20) { |
| 162 | dx = WithSign(flag, (((flag - 10) & 14) << 7) + in[triplet_index]); |
| 163 | dy = 0; |
| 164 | } else if (flag < 84) { |
| 165 | int b0 = flag - 20; |
| 166 | int b1 = in[triplet_index]; |
| 167 | dx = WithSign(flag, 1 + (b0 & 0x30) + (b1 >> 4)); |
| 168 | dy = WithSign(flag >> 1, 1 + ((b0 & 0x0c) << 2) + (b1 & 0x0f)); |
| 169 | } else if (flag < 120) { |
| 170 | int b0 = flag - 84; |
| 171 | dx = WithSign(flag, 1 + ((b0 / 12) << 8) + in[triplet_index]); |
| 172 | dy = WithSign(flag >> 1, |
| 173 | 1 + (((b0 % 12) >> 2) << 8) + in[triplet_index + 1]); |
| 174 | } else if (flag < 124) { |
| 175 | int b2 = in[triplet_index + 1]; |
| 176 | dx = WithSign(flag, (in[triplet_index] << 4) + (b2 >> 4)); |
| 177 | dy = WithSign(flag >> 1, ((b2 & 0x0f) << 8) + in[triplet_index + 2]); |
| 178 | } else { |
| 179 | dx = WithSign(flag, (in[triplet_index] << 8) + in[triplet_index + 1]); |
| 180 | dy = WithSign(flag >> 1, |
| 181 | (in[triplet_index + 2] << 8) + in[triplet_index + 3]); |
| 182 | } |
| 183 | triplet_index += n_data_bytes; |
| 184 | // Possible overflow but coordinate values are not security sensitive |
| 185 | x += dx; |
| 186 | y += dy; |
| 187 | result->push_back(Point()); |
| 188 | Point& back = result->back(); |
| 189 | back.x = x; |
| 190 | back.y = y; |
| 191 | back.on_curve = on_curve; |
| 192 | } |
| 193 | *in_bytes_consumed = triplet_index; |
| 194 | return true; |
| 195 | } |
| 196 | |
| 197 | // This function stores just the point data. On entry, dst points to the |
| 198 | // beginning of a simple glyph. Returns true on success. |
| 199 | bool StorePoints(const std::vector<Point>& points, |
| 200 | unsigned int n_contours, unsigned int instruction_length, |
| 201 | uint8_t* dst, size_t dst_size, size_t* glyph_size) { |
| 202 | // I believe that n_contours < 65536, in which case this is safe. However, a |
| 203 | // comment and/or an assert would be good. |
| 204 | unsigned int flag_offset = kEndPtsOfContoursOffset + 2 * n_contours + 2 + |
| 205 | instruction_length; |
| 206 | int last_flag = -1; |
| 207 | int repeat_count = 0; |
| 208 | int last_x = 0; |
| 209 | int last_y = 0; |
| 210 | unsigned int x_bytes = 0; |
| 211 | unsigned int y_bytes = 0; |
| 212 | |
| 213 | for (unsigned int i = 0; i < points.size(); ++i) { |
| 214 | const Point& point = points[i]; |
| 215 | int flag = point.on_curve ? kGlyfOnCurve : 0; |
| 216 | int dx = point.x - last_x; |
| 217 | int dy = point.y - last_y; |
| 218 | if (dx == 0) { |
| 219 | flag |= kGlyfThisXIsSame; |
| 220 | } else if (dx > -256 && dx < 256) { |
| 221 | flag |= kGlyfXShort | (dx > 0 ? kGlyfThisXIsSame : 0); |
| 222 | x_bytes += 1; |
| 223 | } else { |
| 224 | x_bytes += 2; |
| 225 | } |
| 226 | if (dy == 0) { |
| 227 | flag |= kGlyfThisYIsSame; |
| 228 | } else if (dy > -256 && dy < 256) { |
| 229 | flag |= kGlyfYShort | (dy > 0 ? kGlyfThisYIsSame : 0); |
| 230 | y_bytes += 1; |
| 231 | } else { |
| 232 | y_bytes += 2; |
| 233 | } |
| 234 | |
| 235 | if (flag == last_flag && repeat_count != 255) { |
| 236 | dst[flag_offset - 1] |= kGlyfRepeat; |
| 237 | repeat_count++; |
| 238 | } else { |
| 239 | if (repeat_count != 0) { |
| 240 | if (flag_offset >= dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 241 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 242 | } |
| 243 | dst[flag_offset++] = repeat_count; |
| 244 | } |
| 245 | if (flag_offset >= dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 246 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 247 | } |
| 248 | dst[flag_offset++] = flag; |
| 249 | repeat_count = 0; |
| 250 | } |
| 251 | last_x = point.x; |
| 252 | last_y = point.y; |
| 253 | last_flag = flag; |
| 254 | } |
| 255 | |
| 256 | if (repeat_count != 0) { |
| 257 | if (flag_offset >= dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 258 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 259 | } |
| 260 | dst[flag_offset++] = repeat_count; |
| 261 | } |
| 262 | unsigned int xy_bytes = x_bytes + y_bytes; |
| 263 | if (xy_bytes < x_bytes || |
| 264 | flag_offset + xy_bytes < flag_offset || |
| 265 | flag_offset + xy_bytes > dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 266 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 267 | } |
| 268 | |
| 269 | int x_offset = flag_offset; |
| 270 | int y_offset = flag_offset + x_bytes; |
| 271 | last_x = 0; |
| 272 | last_y = 0; |
| 273 | for (unsigned int i = 0; i < points.size(); ++i) { |
| 274 | int dx = points[i].x - last_x; |
| 275 | if (dx == 0) { |
| 276 | // pass |
| 277 | } else if (dx > -256 && dx < 256) { |
| 278 | dst[x_offset++] = std::abs(dx); |
| 279 | } else { |
| 280 | // will always fit for valid input, but overflow is harmless |
| 281 | x_offset = Store16(dst, x_offset, dx); |
| 282 | } |
| 283 | last_x += dx; |
| 284 | int dy = points[i].y - last_y; |
| 285 | if (dy == 0) { |
| 286 | // pass |
| 287 | } else if (dy > -256 && dy < 256) { |
| 288 | dst[y_offset++] = std::abs(dy); |
| 289 | } else { |
| 290 | y_offset = Store16(dst, y_offset, dy); |
| 291 | } |
| 292 | last_y += dy; |
| 293 | } |
| 294 | *glyph_size = y_offset; |
| 295 | return true; |
| 296 | } |
| 297 | |
| 298 | // Compute the bounding box of the coordinates, and store into a glyf buffer. |
| 299 | // A precondition is that there are at least 10 bytes available. |
| 300 | void ComputeBbox(const std::vector<Point>& points, uint8_t* dst) { |
| 301 | int x_min = 0; |
| 302 | int y_min = 0; |
| 303 | int x_max = 0; |
| 304 | int y_max = 0; |
| 305 | |
| 306 | for (unsigned int i = 0; i < points.size(); ++i) { |
| 307 | int x = points[i].x; |
| 308 | int y = points[i].y; |
| 309 | if (i == 0 || x < x_min) x_min = x; |
| 310 | if (i == 0 || x > x_max) x_max = x; |
| 311 | if (i == 0 || y < y_min) y_min = y; |
| 312 | if (i == 0 || y > y_max) y_max = y; |
| 313 | } |
| 314 | size_t offset = 2; |
| 315 | offset = Store16(dst, offset, x_min); |
| 316 | offset = Store16(dst, offset, y_min); |
| 317 | offset = Store16(dst, offset, x_max); |
| 318 | offset = Store16(dst, offset, y_max); |
| 319 | } |
| 320 | |
| 321 | // Process entire bbox stream. This is done as a separate pass to allow for |
| 322 | // composite bbox computations (an optional more aggressive transform). |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 323 | bool ProcessBboxStream(Buffer* bbox_stream, unsigned int n_glyphs, |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 324 | const std::vector<uint32_t>& loca_values, uint8_t* glyf_buf, |
| 325 | size_t glyf_buf_length) { |
| 326 | const uint8_t* buf = bbox_stream->buffer(); |
| 327 | if (n_glyphs >= 65536 || loca_values.size() != n_glyphs + 1) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 328 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 329 | } |
| 330 | // Safe because n_glyphs is bounded |
| 331 | unsigned int bitmap_length = ((n_glyphs + 31) >> 5) << 2; |
| 332 | if (!bbox_stream->Skip(bitmap_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 333 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 334 | } |
| 335 | for (unsigned int i = 0; i < n_glyphs; ++i) { |
| 336 | if (buf[i >> 3] & (0x80 >> (i & 7))) { |
| 337 | uint32_t loca_offset = loca_values[i]; |
| 338 | if (loca_values[i + 1] - loca_offset < kEndPtsOfContoursOffset) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 339 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 340 | } |
| 341 | if (glyf_buf_length < 2 + 10 || |
| 342 | loca_offset > glyf_buf_length - 2 - 10) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 343 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 344 | } |
| 345 | if (!bbox_stream->Read(glyf_buf + loca_offset + 2, 8)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 346 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 347 | } |
| 348 | } |
| 349 | } |
| 350 | return true; |
| 351 | } |
| 352 | |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 353 | bool ProcessComposite(Buffer* composite_stream, uint8_t* dst, |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 354 | size_t dst_size, size_t* glyph_size, bool* have_instructions) { |
| 355 | size_t start_offset = composite_stream->offset(); |
| 356 | bool we_have_instructions = false; |
| 357 | |
| 358 | uint16_t flags = FLAG_MORE_COMPONENTS; |
| 359 | while (flags & FLAG_MORE_COMPONENTS) { |
| 360 | if (!composite_stream->ReadU16(&flags)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 361 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 362 | } |
| 363 | we_have_instructions |= (flags & FLAG_WE_HAVE_INSTRUCTIONS) != 0; |
| 364 | size_t arg_size = 2; // glyph index |
| 365 | if (flags & FLAG_ARG_1_AND_2_ARE_WORDS) { |
| 366 | arg_size += 4; |
| 367 | } else { |
| 368 | arg_size += 2; |
| 369 | } |
| 370 | if (flags & FLAG_WE_HAVE_A_SCALE) { |
| 371 | arg_size += 2; |
| 372 | } else if (flags & FLAG_WE_HAVE_AN_X_AND_Y_SCALE) { |
| 373 | arg_size += 4; |
| 374 | } else if (flags & FLAG_WE_HAVE_A_TWO_BY_TWO) { |
| 375 | arg_size += 8; |
| 376 | } |
| 377 | if (!composite_stream->Skip(arg_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 378 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 379 | } |
| 380 | } |
| 381 | size_t composite_glyph_size = composite_stream->offset() - start_offset; |
| 382 | if (composite_glyph_size + kCompositeGlyphBegin > dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 383 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 384 | } |
| 385 | Store16(dst, 0, 0xffff); // nContours = -1 for composite glyph |
| 386 | std::memcpy(dst + kCompositeGlyphBegin, |
| 387 | composite_stream->buffer() + start_offset, |
| 388 | composite_glyph_size); |
| 389 | *glyph_size = kCompositeGlyphBegin + composite_glyph_size; |
| 390 | *have_instructions = we_have_instructions; |
| 391 | return true; |
| 392 | } |
| 393 | |
| 394 | // Build TrueType loca table |
| 395 | bool StoreLoca(const std::vector<uint32_t>& loca_values, int index_format, |
| 396 | uint8_t* dst, size_t dst_size) { |
| 397 | const uint64_t loca_size = loca_values.size(); |
| 398 | const uint64_t offset_size = index_format ? 4 : 2; |
| 399 | if ((loca_size << 2) >> 2 != loca_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 400 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 401 | } |
| 402 | if (offset_size * loca_size > dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 403 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 404 | } |
| 405 | size_t offset = 0; |
| 406 | for (size_t i = 0; i < loca_values.size(); ++i) { |
| 407 | uint32_t value = loca_values[i]; |
| 408 | if (index_format) { |
| 409 | offset = StoreU32(dst, offset, value); |
| 410 | } else { |
| 411 | offset = Store16(dst, offset, value >> 1); |
| 412 | } |
| 413 | } |
| 414 | return true; |
| 415 | } |
| 416 | |
| 417 | // Reconstruct entire glyf table based on transformed original |
| 418 | bool ReconstructGlyf(const uint8_t* data, size_t data_size, |
| 419 | uint8_t* dst, size_t dst_size, |
| 420 | uint8_t* loca_buf, size_t loca_size) { |
| 421 | static const int kNumSubStreams = 7; |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 422 | Buffer file(data, data_size); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 423 | uint32_t version; |
| 424 | std::vector<std::pair<const uint8_t*, size_t> > substreams(kNumSubStreams); |
| 425 | |
| 426 | if (!file.ReadU32(&version)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 427 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 428 | } |
| 429 | uint16_t num_glyphs; |
| 430 | uint16_t index_format; |
| 431 | if (!file.ReadU16(&num_glyphs) || |
| 432 | !file.ReadU16(&index_format)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 433 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 434 | } |
| 435 | unsigned int offset = (2 + kNumSubStreams) * 4; |
| 436 | if (offset > data_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 437 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 438 | } |
| 439 | // Invariant from here on: data_size >= offset |
| 440 | for (int i = 0; i < kNumSubStreams; ++i) { |
| 441 | uint32_t substream_size; |
| 442 | if (!file.ReadU32(&substream_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 443 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 444 | } |
| 445 | if (substream_size > data_size - offset) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 446 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 447 | } |
| 448 | substreams[i] = std::make_pair(data + offset, substream_size); |
| 449 | offset += substream_size; |
| 450 | } |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 451 | Buffer n_contour_stream(substreams[0].first, substreams[0].second); |
| 452 | Buffer n_points_stream(substreams[1].first, substreams[1].second); |
| 453 | Buffer flag_stream(substreams[2].first, substreams[2].second); |
| 454 | Buffer glyph_stream(substreams[3].first, substreams[3].second); |
| 455 | Buffer composite_stream(substreams[4].first, substreams[4].second); |
| 456 | Buffer bbox_stream(substreams[5].first, substreams[5].second); |
| 457 | Buffer instruction_stream(substreams[6].first, substreams[6].second); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 458 | |
| 459 | std::vector<uint32_t> loca_values(num_glyphs + 1); |
| 460 | std::vector<unsigned int> n_points_vec; |
| 461 | std::vector<Point> points; |
| 462 | uint32_t loca_offset = 0; |
| 463 | for (unsigned int i = 0; i < num_glyphs; ++i) { |
| 464 | size_t glyph_size = 0; |
| 465 | uint16_t n_contours = 0; |
| 466 | if (!n_contour_stream.ReadU16(&n_contours)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 467 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 468 | } |
| 469 | uint8_t* glyf_dst = dst + loca_offset; |
| 470 | size_t glyf_dst_size = dst_size - loca_offset; |
| 471 | if (n_contours == 0xffff) { |
| 472 | // composite glyph |
| 473 | bool have_instructions = false; |
| 474 | unsigned int instruction_size = 0; |
| 475 | if (!ProcessComposite(&composite_stream, glyf_dst, glyf_dst_size, |
| 476 | &glyph_size, &have_instructions)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 477 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 478 | } |
| 479 | if (have_instructions) { |
| 480 | if (!Read255UShort(&glyph_stream, &instruction_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 481 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 482 | } |
| 483 | if (instruction_size + 2 > glyf_dst_size - glyph_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 484 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 485 | } |
| 486 | Store16(glyf_dst, glyph_size, instruction_size); |
| 487 | if (!instruction_stream.Read(glyf_dst + glyph_size + 2, |
| 488 | instruction_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 489 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 490 | } |
| 491 | glyph_size += instruction_size + 2; |
| 492 | } |
| 493 | } else if (n_contours > 0) { |
| 494 | // simple glyph |
| 495 | n_points_vec.clear(); |
| 496 | points.clear(); |
| 497 | unsigned int total_n_points = 0; |
| 498 | unsigned int n_points_contour; |
| 499 | for (unsigned int j = 0; j < n_contours; ++j) { |
| 500 | if (!Read255UShort(&n_points_stream, &n_points_contour)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 501 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 502 | } |
| 503 | n_points_vec.push_back(n_points_contour); |
| 504 | if (total_n_points + n_points_contour < total_n_points) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 505 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 506 | } |
| 507 | total_n_points += n_points_contour; |
| 508 | } |
| 509 | unsigned int flag_size = total_n_points; |
| 510 | if (flag_size > flag_stream.length() - flag_stream.offset()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 511 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 512 | } |
| 513 | const uint8_t* flags_buf = flag_stream.buffer() + flag_stream.offset(); |
| 514 | const uint8_t* triplet_buf = glyph_stream.buffer() + |
| 515 | glyph_stream.offset(); |
| 516 | size_t triplet_size = glyph_stream.length() - glyph_stream.offset(); |
| 517 | size_t triplet_bytes_consumed = 0; |
| 518 | if (!TripletDecode(flags_buf, triplet_buf, triplet_size, total_n_points, |
| 519 | &points, &triplet_bytes_consumed)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 520 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 521 | } |
| 522 | const uint32_t header_and_endpts_contours_size = |
| 523 | kEndPtsOfContoursOffset + 2 * n_contours; |
| 524 | if (glyf_dst_size < header_and_endpts_contours_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 525 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 526 | } |
| 527 | Store16(glyf_dst, 0, n_contours); |
| 528 | ComputeBbox(points, glyf_dst); |
| 529 | size_t offset = kEndPtsOfContoursOffset; |
| 530 | int end_point = -1; |
| 531 | for (unsigned int contour_ix = 0; contour_ix < n_contours; ++contour_ix) { |
| 532 | end_point += n_points_vec[contour_ix]; |
| 533 | if (end_point >= 65536) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 534 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 535 | } |
| 536 | offset = Store16(glyf_dst, offset, end_point); |
| 537 | } |
| 538 | if (!flag_stream.Skip(flag_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 539 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 540 | } |
| 541 | if (!glyph_stream.Skip(triplet_bytes_consumed)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 542 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 543 | } |
| 544 | unsigned int instruction_size; |
| 545 | if (!Read255UShort(&glyph_stream, &instruction_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 546 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 547 | } |
| 548 | if (glyf_dst_size - header_and_endpts_contours_size < |
| 549 | instruction_size + 2) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 550 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 551 | } |
| 552 | uint8_t* instruction_dst = glyf_dst + header_and_endpts_contours_size; |
| 553 | Store16(instruction_dst, 0, instruction_size); |
| 554 | if (!instruction_stream.Read(instruction_dst + 2, instruction_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 555 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 556 | } |
| 557 | if (!StorePoints(points, n_contours, instruction_size, |
| 558 | glyf_dst, glyf_dst_size, &glyph_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 559 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 560 | } |
| 561 | } else { |
| 562 | glyph_size = 0; |
| 563 | } |
| 564 | loca_values[i] = loca_offset; |
| 565 | if (glyph_size + 3 < glyph_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 566 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 567 | } |
| 568 | glyph_size = Round4(glyph_size); |
| 569 | if (glyph_size > dst_size - loca_offset) { |
| 570 | // This shouldn't happen, but this test defensively maintains the |
| 571 | // invariant that loca_offset <= dst_size. |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 572 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 573 | } |
| 574 | loca_offset += glyph_size; |
| 575 | } |
| 576 | loca_values[num_glyphs] = loca_offset; |
| 577 | if (!ProcessBboxStream(&bbox_stream, num_glyphs, loca_values, |
| 578 | dst, dst_size)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 579 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 580 | } |
| 581 | return StoreLoca(loca_values, index_format, loca_buf, loca_size); |
| 582 | } |
| 583 | |
| 584 | // This is linear search, but could be changed to binary because we |
| 585 | // do have a guarantee that the tables are sorted by tag. But the total |
| 586 | // cpu time is expected to be very small in any case. |
| 587 | const Table* FindTable(const std::vector<Table>& tables, uint32_t tag) { |
| 588 | size_t n_tables = tables.size(); |
| 589 | for (size_t i = 0; i < n_tables; ++i) { |
| 590 | if (tables[i].tag == tag) { |
| 591 | return &tables[i]; |
| 592 | } |
| 593 | } |
| 594 | return NULL; |
| 595 | } |
| 596 | |
| 597 | bool ReconstructTransformed(const std::vector<Table>& tables, uint32_t tag, |
| 598 | const uint8_t* transformed_buf, size_t transformed_size, |
| 599 | uint8_t* dst, size_t dst_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 600 | if (tag == kGlyfTableTag) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 601 | const Table* glyf_table = FindTable(tables, tag); |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 602 | const Table* loca_table = FindTable(tables, kLocaTableTag); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 603 | if (glyf_table == NULL || loca_table == NULL) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 604 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 605 | } |
| 606 | if (static_cast<uint64_t>(glyf_table->dst_offset + glyf_table->dst_length) > |
| 607 | dst_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 608 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 609 | } |
| 610 | if (static_cast<uint64_t>(loca_table->dst_offset + loca_table->dst_length) > |
| 611 | dst_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 612 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 613 | } |
| 614 | return ReconstructGlyf(transformed_buf, transformed_size, |
| 615 | dst + glyf_table->dst_offset, glyf_table->dst_length, |
| 616 | dst + loca_table->dst_offset, loca_table->dst_length); |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 617 | } else if (tag == kLocaTableTag) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 618 | // processing was already done by glyf table, but validate |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 619 | if (!FindTable(tables, kGlyfTableTag)) { |
| 620 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 621 | } |
| 622 | } else { |
| 623 | // transform for the tag is not known |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 624 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 625 | } |
| 626 | return true; |
| 627 | } |
| 628 | |
| 629 | uint32_t ComputeChecksum(const uint8_t* buf, size_t size) { |
| 630 | uint32_t checksum = 0; |
| 631 | for (size_t i = 0; i < size; i += 4) { |
| 632 | // We assume the addition is mod 2^32, which is valid because unsigned |
| 633 | checksum += (buf[i] << 24) | (buf[i + 1] << 16) | |
| 634 | (buf[i + 2] << 8) | buf[i + 3]; |
| 635 | } |
| 636 | return checksum; |
| 637 | } |
| 638 | |
| 639 | bool FixChecksums(const std::vector<Table>& tables, uint8_t* dst) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 640 | const Table* head_table = FindTable(tables, kHeadTableTag); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 641 | if (head_table == NULL || |
| 642 | head_table->dst_length < kCheckSumAdjustmentOffset + 4) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 643 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 644 | } |
| 645 | size_t adjustment_offset = head_table->dst_offset + kCheckSumAdjustmentOffset; |
| 646 | StoreU32(dst, adjustment_offset, 0); |
| 647 | size_t n_tables = tables.size(); |
| 648 | uint32_t file_checksum = 0; |
| 649 | for (size_t i = 0; i < n_tables; ++i) { |
| 650 | const Table* table = &tables[i]; |
| 651 | size_t table_length = table->dst_length; |
| 652 | uint8_t* table_data = dst + table->dst_offset; |
| 653 | uint32_t checksum = ComputeChecksum(table_data, table_length); |
| 654 | StoreU32(dst, kSfntHeaderSize + i * kSfntEntrySize + 4, checksum); |
| 655 | file_checksum += checksum; |
| 656 | } |
| 657 | file_checksum += ComputeChecksum(dst, |
| 658 | kSfntHeaderSize + kSfntEntrySize * n_tables); |
| 659 | uint32_t checksum_adjustment = 0xb1b0afba - file_checksum; |
| 660 | StoreU32(dst, adjustment_offset, checksum_adjustment); |
| 661 | return true; |
| 662 | } |
| 663 | |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 664 | bool Woff2Uncompress(uint8_t* dst_buf, size_t dst_size, |
Roderick Sheeter | 2ec0cb8 | 2014-05-07 11:01:07 -0700 | [diff] [blame] | 665 | const uint8_t* src_buf, size_t src_size) { |
| 666 | size_t uncompressed_size = dst_size; |
| 667 | int ok = BrotliDecompressBuffer(src_size, src_buf, |
| 668 | &uncompressed_size, dst_buf); |
| 669 | if (!ok || uncompressed_size != dst_size) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 670 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 671 | } |
Roderick Sheeter | 2ec0cb8 | 2014-05-07 11:01:07 -0700 | [diff] [blame] | 672 | return true; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 673 | } |
| 674 | |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 675 | bool ReadShortDirectory(Buffer* file, std::vector<Table>* tables, |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 676 | size_t num_tables) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 677 | for (size_t i = 0; i < num_tables; ++i) { |
| 678 | Table* table = &(*tables)[i]; |
| 679 | uint8_t flag_byte; |
| 680 | if (!file->ReadU8(&flag_byte)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 681 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 682 | } |
| 683 | uint32_t tag; |
David Kuettel | 47c5016 | 2014-04-29 17:47:03 -0700 | [diff] [blame] | 684 | if ((flag_byte & 0x3f) == 0x3f) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 685 | if (!file->ReadU32(&tag)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 686 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 687 | } |
| 688 | } else { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 689 | tag = kKnownTags[flag_byte & 0x3f]; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 690 | } |
David Kuettel | 47c5016 | 2014-04-29 17:47:03 -0700 | [diff] [blame] | 691 | // Bits 6 and 7 are reserved and must be 0. |
| 692 | if ((flag_byte & 0xC0) != 0) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 693 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 694 | } |
Roderick Sheeter | 2ec0cb8 | 2014-05-07 11:01:07 -0700 | [diff] [blame] | 695 | uint32_t flags = 0; |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 696 | if (i > 0) { |
| 697 | flags |= kWoff2FlagsContinueStream; |
| 698 | } |
David Kuettel | 47c5016 | 2014-04-29 17:47:03 -0700 | [diff] [blame] | 699 | // Always transform the glyf and loca tables |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 700 | if (tag == kGlyfTableTag || tag == kLocaTableTag) { |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 701 | flags |= kWoff2FlagsTransform; |
| 702 | } |
| 703 | uint32_t dst_length; |
| 704 | if (!ReadBase128(file, &dst_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 705 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 706 | } |
| 707 | uint32_t transform_length = dst_length; |
| 708 | if ((flags & kWoff2FlagsTransform) != 0) { |
| 709 | if (!ReadBase128(file, &transform_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 710 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 711 | } |
| 712 | } |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 713 | table->tag = tag; |
| 714 | table->flags = flags; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 715 | table->transform_length = transform_length; |
| 716 | table->dst_length = dst_length; |
| 717 | } |
| 718 | return true; |
| 719 | } |
| 720 | |
| 721 | } // namespace |
| 722 | |
| 723 | size_t ComputeWOFF2FinalSize(const uint8_t* data, size_t length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 724 | Buffer file(data, length); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 725 | uint32_t total_length; |
| 726 | |
| 727 | if (!file.Skip(16) || |
| 728 | !file.ReadU32(&total_length)) { |
| 729 | return 0; |
| 730 | } |
| 731 | return total_length; |
| 732 | } |
| 733 | |
| 734 | bool ConvertWOFF2ToTTF(uint8_t* result, size_t result_length, |
| 735 | const uint8_t* data, size_t length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 736 | Buffer file(data, length); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 737 | |
| 738 | uint32_t signature; |
| 739 | uint32_t flavor; |
| 740 | if (!file.ReadU32(&signature) || signature != kWoff2Signature || |
| 741 | !file.ReadU32(&flavor)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 742 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 743 | } |
| 744 | |
| 745 | // TODO(user): Should call IsValidVersionTag() here. |
| 746 | |
| 747 | uint32_t reported_length; |
| 748 | if (!file.ReadU32(&reported_length) || length != reported_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 749 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 750 | } |
| 751 | uint16_t num_tables; |
| 752 | if (!file.ReadU16(&num_tables) || !num_tables) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 753 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 754 | } |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 755 | // We don't care about these fields of the header: |
Zoltan Szabadka | 494c85c | 2014-03-20 14:35:41 +0100 | [diff] [blame] | 756 | // uint16_t reserved |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 757 | // uint32_t total_sfnt_size |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 758 | if (!file.Skip(6)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 759 | return FONT_COMPRESSION_FAILURE(); |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 760 | } |
| 761 | uint32_t compressed_length; |
| 762 | if (!file.ReadU32(&compressed_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 763 | return FONT_COMPRESSION_FAILURE(); |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 764 | } |
| 765 | // We don't care about these fields of the header: |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 766 | // uint16_t major_version, minor_version |
| 767 | // uint32_t meta_offset, meta_length, meta_orig_length |
| 768 | // uint32_t priv_offset, priv_length |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 769 | if (!file.Skip(24)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 770 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 771 | } |
| 772 | std::vector<Table> tables(num_tables); |
| 773 | // Note: change below to ReadLongDirectory to enable long format. |
| 774 | if (!ReadShortDirectory(&file, &tables, num_tables)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 775 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 776 | } |
| 777 | uint64_t src_offset = file.offset(); |
| 778 | uint64_t dst_offset = kSfntHeaderSize + |
| 779 | kSfntEntrySize * static_cast<uint64_t>(num_tables); |
| 780 | uint64_t uncompressed_sum = 0; |
| 781 | for (uint16_t i = 0; i < num_tables; ++i) { |
| 782 | Table* table = &tables[i]; |
| 783 | table->src_offset = src_offset; |
Zoltan Szabadka | 22e2c32 | 2014-03-27 16:13:13 +0100 | [diff] [blame] | 784 | table->src_length = (i == 0 ? compressed_length : 0); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 785 | src_offset += table->src_length; |
| 786 | if (src_offset > std::numeric_limits<uint32_t>::max()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 787 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 788 | } |
| 789 | src_offset = Round4(src_offset); // TODO: reconsider |
| 790 | table->dst_offset = dst_offset; |
| 791 | dst_offset += table->dst_length; |
| 792 | if (dst_offset > std::numeric_limits<uint32_t>::max()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 793 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 794 | } |
| 795 | dst_offset = Round4(dst_offset); |
Roderick Sheeter | 2ec0cb8 | 2014-05-07 11:01:07 -0700 | [diff] [blame] | 796 | |
| 797 | uncompressed_sum += table->src_length; |
| 798 | if (uncompressed_sum > std::numeric_limits<uint32_t>::max()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 799 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 800 | } |
| 801 | } |
| 802 | // Enforce same 30M limit on uncompressed tables as OTS |
| 803 | if (uncompressed_sum > 30 * 1024 * 1024) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 804 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 805 | } |
| 806 | if (src_offset > length || dst_offset > result_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 807 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 808 | } |
| 809 | |
| 810 | const uint32_t sfnt_header_and_table_directory_size = 12 + 16 * num_tables; |
| 811 | if (sfnt_header_and_table_directory_size > result_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 812 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 813 | } |
| 814 | |
| 815 | // Start building the font |
| 816 | size_t offset = 0; |
| 817 | offset = StoreU32(result, offset, flavor); |
| 818 | offset = Store16(result, offset, num_tables); |
| 819 | unsigned max_pow2 = 0; |
| 820 | while (1u << (max_pow2 + 1) <= num_tables) { |
| 821 | max_pow2++; |
| 822 | } |
| 823 | const uint16_t output_search_range = (1u << max_pow2) << 4; |
| 824 | offset = Store16(result, offset, output_search_range); |
| 825 | offset = Store16(result, offset, max_pow2); |
| 826 | offset = Store16(result, offset, (num_tables << 4) - output_search_range); |
| 827 | for (uint16_t i = 0; i < num_tables; ++i) { |
| 828 | const Table* table = &tables[i]; |
| 829 | offset = StoreU32(result, offset, table->tag); |
| 830 | offset = StoreU32(result, offset, 0); // checksum, to fill in later |
| 831 | offset = StoreU32(result, offset, table->dst_offset); |
| 832 | offset = StoreU32(result, offset, table->dst_length); |
| 833 | } |
| 834 | std::vector<uint8_t> uncompressed_buf; |
| 835 | bool continue_valid = false; |
| 836 | const uint8_t* transform_buf = NULL; |
| 837 | for (uint16_t i = 0; i < num_tables; ++i) { |
| 838 | const Table* table = &tables[i]; |
| 839 | uint32_t flags = table->flags; |
| 840 | const uint8_t* src_buf = data + table->src_offset; |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 841 | size_t transform_length = table->transform_length; |
| 842 | if ((flags & kWoff2FlagsContinueStream) != 0) { |
| 843 | if (!continue_valid) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 844 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 845 | } |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 846 | } else if ((flags & kWoff2FlagsContinueStream) == 0) { |
| 847 | uint64_t total_size = transform_length; |
| 848 | for (uint16_t j = i + 1; j < num_tables; ++j) { |
| 849 | if ((tables[j].flags & kWoff2FlagsContinueStream) == 0) { |
| 850 | break; |
| 851 | } |
| 852 | total_size += tables[j].transform_length; |
| 853 | if (total_size > std::numeric_limits<uint32_t>::max()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 854 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 855 | } |
| 856 | } |
| 857 | uncompressed_buf.resize(total_size); |
| 858 | if (!Woff2Uncompress(&uncompressed_buf[0], total_size, |
Roderick Sheeter | 2ec0cb8 | 2014-05-07 11:01:07 -0700 | [diff] [blame] | 859 | src_buf, compressed_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 860 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 861 | } |
| 862 | transform_buf = &uncompressed_buf[0]; |
| 863 | continue_valid = true; |
| 864 | } else { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 865 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 866 | } |
| 867 | |
| 868 | if ((flags & kWoff2FlagsTransform) == 0) { |
| 869 | if (transform_length != table->dst_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 870 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 871 | } |
| 872 | if (static_cast<uint64_t>(table->dst_offset + transform_length) > |
| 873 | result_length) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 874 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 875 | } |
| 876 | std::memcpy(result + table->dst_offset, transform_buf, |
| 877 | transform_length); |
| 878 | } else { |
| 879 | if (!ReconstructTransformed(tables, table->tag, |
| 880 | transform_buf, transform_length, result, result_length)) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 881 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 882 | } |
| 883 | } |
| 884 | if (continue_valid) { |
| 885 | transform_buf += transform_length; |
Kenichi Ishibashi | c75ed76 | 2014-06-04 08:29:53 +0900 | [diff] [blame^] | 886 | if (transform_buf > &uncompressed_buf[0] + uncompressed_buf.size()) { |
Kenichi Ishibashi | 142d888 | 2014-05-30 09:06:32 +0900 | [diff] [blame] | 887 | return FONT_COMPRESSION_FAILURE(); |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 888 | } |
| 889 | } |
| 890 | } |
| 891 | |
| 892 | return FixChecksums(tables, result); |
| 893 | } |
| 894 | |
Roderick Sheeter | 437bbad | 2013-11-19 14:32:56 -0800 | [diff] [blame] | 895 | } // namespace woff2 |