1 /*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "src/core/SkFontDescriptor.h"
9
10 #include "include/core/SkData.h"
11 #include "include/core/SkRefCnt.h"
12 #include "include/core/SkStream.h"
13 #include "include/private/base/SkAssert.h"
14 #include "include/private/base/SkTFitsIn.h"
15 #include "include/private/base/SkTo.h"
16 #include "src/core/SkStreamPriv.h"
17
18 #include <cstddef>
19 #include <cstdint>
20 enum {
21 kInvalid = 0x00,
22
23 // Related to a font request.
24 kFontFamilyName = 0x01, // int length, data[length]
25 kFullName = 0x04, // int length, data[length]
26 kPostscriptName = 0x06, // int length, data[length]
27 kWeight = 0x10, // scalar (1 - 1000)
28 kWidth = 0x11, // scalar (percentage, 100 is 'normal')
29 kSlant = 0x12, // scalar (cw angle, 14 is a normal right leaning oblique)
30 kItalic = 0x13, // scalar (0 is Roman, 1 is fully Italic)
31
32 // Related to font data. Can also be used with a requested font.
33 kPaletteIndex = 0xF8, // int
34 kPaletteEntryOverrides = 0xF9, // int count, (int, u32)[count]
35 kFontVariation = 0xFA, // int count, (u32, scalar)[count]
36
37 // Related to font data.
38 kFactoryId = 0xFC, // int
39 kFontIndex = 0xFD, // int
40 kSentinel = 0xFF, // no data
41 };
42
SkFontDescriptor()43 SkFontDescriptor::SkFontDescriptor() { }
44
read_string(SkStream * stream,SkString * string)45 [[nodiscard]] static bool read_string(SkStream* stream, SkString* string) {
46 size_t length;
47 if (!stream->readPackedUInt(&length)) { return false; }
48 if (length > 0) {
49 if (StreamRemainingLengthIsBelow(stream, length)) {
50 return false;
51 }
52 string->resize(length);
53 if (stream->read(string->data(), length) != length) { return false; }
54 }
55 return true;
56 }
57
write_string(SkWStream * stream,const SkString & string,uint32_t id)58 static bool write_string(SkWStream* stream, const SkString& string, uint32_t id) {
59 if (string.isEmpty()) { return true; }
60 return stream->writePackedUInt(id) &&
61 stream->writePackedUInt(string.size()) &&
62 stream->write(string.c_str(), string.size());
63 }
64
write_uint(SkWStream * stream,size_t n,uint32_t id)65 static bool write_uint(SkWStream* stream, size_t n, uint32_t id) {
66 return stream->writePackedUInt(id) &&
67 stream->writePackedUInt(n);
68 }
69
write_scalar(SkWStream * stream,SkScalar n,uint32_t id)70 static bool write_scalar(SkWStream* stream, SkScalar n, uint32_t id) {
71 return stream->writePackedUInt(id) &&
72 stream->writeScalar(n);
73 }
74
read_id(SkStream * stream)75 [[nodiscard]] static size_t read_id(SkStream* stream) {
76 size_t i;
77 if (!stream->readPackedUInt(&i)) { return kInvalid; }
78 return i;
79 }
80
81 static constexpr SkScalar usWidths[9] {
82 1, 2, 3, 4, 5, 6, 7, 8, 9
83 };
84 static constexpr SkScalar width_for_usWidth[0x10] = {
85 50,
86 50, 62.5, 75, 87.5, 100, 112.5, 125, 150, 200,
87 200, 200, 200, 200, 200, 200
88 };
89
Deserialize(SkStream * stream,SkFontDescriptor * result)90 bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
91 size_t factoryId;
92 using FactoryIdType = decltype(result->fFactoryId);
93
94 size_t coordinateCount;
95 using CoordinateCountType = decltype(result->fCoordinateCount);
96
97 size_t index;
98 using CollectionIndexType = decltype(result->fCollectionIndex);
99
100 size_t paletteIndex;
101 using PaletteIndexType = decltype(result->fPaletteIndex);
102
103 size_t paletteEntryOverrideCount;
104 using PaletteEntryOverrideCountType = decltype(result->fPaletteEntryOverrideCount);
105
106 size_t paletteEntryOverrideIndex;
107 using PaletteEntryOverrideIndexType = decltype(result->fPaletteEntryOverrides[0].index);
108
109 SkScalar weight = SkFontStyle::kNormal_Weight;
110 SkScalar width = SkFontStyle::kNormal_Width;
111 SkScalar slant = 0;
112 SkScalar italic = 0;
113
114 size_t styleBits;
115 if (!stream->readPackedUInt(&styleBits)) { return false; }
116 weight = ((styleBits >> 16) & 0xFFFF);
117 width = ((styleBits >> 8) & 0x000F)[width_for_usWidth];
118 slant = ((styleBits >> 0) & 0x000F) != SkFontStyle::kUpright_Slant ? 14 : 0;
119 italic = ((styleBits >> 0) & 0x000F) == SkFontStyle::kItalic_Slant ? 1 : 0;
120
121 for (size_t id; (id = read_id(stream)) != kSentinel;) {
122 switch (id) {
123 case kFontFamilyName:
124 if (!read_string(stream, &result->fFamilyName)) { return false; }
125 break;
126 case kFullName:
127 if (!read_string(stream, &result->fFullName)) { return false; }
128 break;
129 case kPostscriptName:
130 if (!read_string(stream, &result->fPostscriptName)) { return false; }
131 break;
132 case kWeight:
133 if (!stream->readScalar(&weight)) { return false; }
134 break;
135 case kWidth:
136 if (!stream->readScalar(&width)) { return false; }
137 break;
138 case kSlant:
139 if (!stream->readScalar(&slant)) { return false; }
140 break;
141 case kItalic:
142 if (!stream->readScalar(&italic)) { return false; }
143 break;
144 case kFontVariation:
145 if (!stream->readPackedUInt(&coordinateCount)) { return false; }
146 if (!SkTFitsIn<CoordinateCountType>(coordinateCount)) { return false; }
147 if (StreamRemainingLengthIsBelow(stream, coordinateCount)) {
148 return false;
149 }
150 result->fCoordinateCount = SkTo<CoordinateCountType>(coordinateCount);
151
152 result->fVariation.reset(coordinateCount);
153 for (size_t i = 0; i < coordinateCount; ++i) {
154 if (!stream->readU32(&result->fVariation[i].axis)) { return false; }
155 if (!stream->readScalar(&result->fVariation[i].value)) { return false; }
156 }
157 break;
158 case kFontIndex:
159 if (!stream->readPackedUInt(&index)) { return false; }
160 if (!SkTFitsIn<CollectionIndexType>(index)) { return false; }
161 result->fCollectionIndex = SkTo<CollectionIndexType>(index);
162 break;
163 case kPaletteIndex:
164 if (!stream->readPackedUInt(&paletteIndex)) { return false; }
165 if (!SkTFitsIn<PaletteIndexType>(paletteIndex)) { return false; }
166 result->fPaletteIndex = SkTo<PaletteIndexType>(paletteIndex);
167 break;
168 case kPaletteEntryOverrides:
169 if (!stream->readPackedUInt(&paletteEntryOverrideCount)) { return false; }
170 if (!SkTFitsIn<PaletteEntryOverrideCountType>(paletteEntryOverrideCount)) {
171 return false;
172 }
173 if (StreamRemainingLengthIsBelow(stream, paletteEntryOverrideCount)) {
174 return false;
175 }
176 result->fPaletteEntryOverrideCount =
177 SkTo<PaletteEntryOverrideCountType>(paletteEntryOverrideCount);
178
179 result->fPaletteEntryOverrides.reset(paletteEntryOverrideCount);
180 for (size_t i = 0; i < paletteEntryOverrideCount; ++i) {
181 if (!stream->readPackedUInt(&paletteEntryOverrideIndex)) { return false; }
182 if (!SkTFitsIn<PaletteEntryOverrideIndexType>(paletteEntryOverrideIndex)) {
183 return false;
184 }
185 result->fPaletteEntryOverrides[i].index =
186 SkTo<PaletteEntryOverrideIndexType>(paletteEntryOverrideIndex);
187 if (!stream->readU32(&result->fPaletteEntryOverrides[i].color)) {
188 return false;
189 }
190 }
191 break;
192 case kFactoryId:
193 if (!stream->readPackedUInt(&factoryId)) { return false; }
194 if (!SkTFitsIn<FactoryIdType>(factoryId)) { return false; }
195 result->fFactoryId = SkTo<FactoryIdType>(factoryId);
196 break;
197 default:
198 SkDEBUGFAIL("Unknown id used by a font descriptor");
199 return false;
200 }
201 }
202
203 SkFontStyle::Slant slantEnum = SkFontStyle::kUpright_Slant;
204 if (slant != 0) { slantEnum = SkFontStyle::kOblique_Slant; }
205 if (0 < italic) { slantEnum = SkFontStyle::kItalic_Slant; }
206 SkFontStyle::Width widthEnum = SkFontStyleWidthForWidthAxisValue(width);
207 result->fStyle = SkFontStyle(SkScalarRoundToInt(weight), widthEnum, slantEnum);
208
209 size_t length;
210 if (!stream->readPackedUInt(&length)) { return false; }
211 if (length > 0) {
212 if (StreamRemainingLengthIsBelow(stream, length)) {
213 return false;
214 }
215 sk_sp<SkData> data(SkData::MakeUninitialized(length));
216 if (stream->read(data->writable_data(), length) != length) {
217 SkDEBUGFAIL("Could not read font data");
218 return false;
219 }
220 result->fStream = SkMemoryStream::Make(std::move(data));
221 }
222 return true;
223 }
224
serialize(SkWStream * stream) const225 void SkFontDescriptor::serialize(SkWStream* stream) const {
226 uint32_t styleBits = (fStyle.weight() << 16) | (fStyle.width() << 8) | (fStyle.slant());
227 stream->writePackedUInt(styleBits);
228
229 write_string(stream, fFamilyName, kFontFamilyName);
230 write_string(stream, fFullName, kFullName);
231 write_string(stream, fPostscriptName, kPostscriptName);
232
233 write_scalar(stream, fStyle.weight(), kWeight);
234 write_scalar(stream, fStyle.width()[width_for_usWidth], kWidth);
235 write_scalar(stream, fStyle.slant() == SkFontStyle::kUpright_Slant ? 0 : 14, kSlant);
236 write_scalar(stream, fStyle.slant() == SkFontStyle::kItalic_Slant ? 1 : 0, kItalic);
237
238 if (fCollectionIndex > 0) {
239 write_uint(stream, fCollectionIndex, kFontIndex);
240 }
241 if (fPaletteIndex > 0) {
242 write_uint(stream, fPaletteIndex, kPaletteIndex);
243 }
244 if (fCoordinateCount > 0) {
245 write_uint(stream, fCoordinateCount, kFontVariation);
246 for (int i = 0; i < fCoordinateCount; ++i) {
247 stream->write32(fVariation[i].axis);
248 stream->writeScalar(fVariation[i].value);
249 }
250 }
251 if (fPaletteEntryOverrideCount > 0) {
252 write_uint(stream, fPaletteEntryOverrideCount, kPaletteEntryOverrides);
253 for (int i = 0; i < fPaletteEntryOverrideCount; ++i) {
254 stream->writePackedUInt(fPaletteEntryOverrides[i].index);
255 stream->write32(fPaletteEntryOverrides[i].color);
256 }
257 }
258
259 write_uint(stream, fFactoryId, kFactoryId);
260
261 stream->writePackedUInt(kSentinel);
262
263 if (fStream) {
264 std::unique_ptr<SkStreamAsset> fontStream = fStream->duplicate();
265 size_t length = fontStream->getLength();
266 stream->writePackedUInt(length);
267 stream->writeStream(fontStream.get(), length);
268 } else {
269 stream->writePackedUInt(0);
270 }
271 }
272
SkFontStyleWidthForWidthAxisValue(SkScalar width)273 SkFontStyle::Width SkFontDescriptor::SkFontStyleWidthForWidthAxisValue(SkScalar width) {
274 int usWidth = SkScalarRoundToInt(SkScalarInterpFunc(width, &width_for_usWidth[1], usWidths, 9));
275 return static_cast<SkFontStyle::Width>(usWidth);
276 }
277