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 "include/core/SkData.h"
9 #include "include/core/SkStream.h"
10 #include "src/core/SkFontDescriptor.h"
11 #include "src/core/SkStreamPriv.h"
12
13 enum {
14 kInvalid = 0x00,
15
16 // Related to a font request.
17 kFontFamilyName = 0x01, // int length, data[length]
18 kFullName = 0x04, // int length, data[length]
19 kPostscriptName = 0x06, // int length, data[length]
20 kWeight = 0x10, // scalar (1 - 1000)
21 kWidth = 0x11, // scalar (percentage, 100 is 'normal')
22 kSlant = 0x12, // scalar (cw angle, 14 is a normal right leaning oblique)
23 kItalic = 0x13, // scalar (0 is Roman, 1 is fully Italic)
24
25 // Related to font data. Can also be used with a requested font.
26 kPaletteIndex = 0xF8, // int
27 kPaletteEntryOverrides = 0xF9, // int count, (int, u32)[count]
28 kFontVariation = 0xFA, // int count, (u32, scalar)[count]
29
30 // Related to font data.
31 kFactoryId = 0xFC, // int
32 kFontIndex = 0xFD, // int
33 kSentinel = 0xFF, // no data
34 };
35
SkFontDescriptor()36 SkFontDescriptor::SkFontDescriptor() { }
37
read_string(SkStream * stream,SkString * string)38 static bool SK_WARN_UNUSED_RESULT read_string(SkStream* stream, SkString* string) {
39 size_t length;
40 if (!stream->readPackedUInt(&length)) { return false; }
41 if (length > 0) {
42 if (StreamRemainingLengthIsBelow(stream, length)) {
43 return false;
44 }
45 string->resize(length);
46 if (stream->read(string->data(), length) != length) { return false; }
47 }
48 return true;
49 }
50
write_string(SkWStream * stream,const SkString & string,uint32_t id)51 static bool write_string(SkWStream* stream, const SkString& string, uint32_t id) {
52 if (string.isEmpty()) { return true; }
53 return stream->writePackedUInt(id) &&
54 stream->writePackedUInt(string.size()) &&
55 stream->write(string.c_str(), string.size());
56 }
57
write_uint(SkWStream * stream,size_t n,uint32_t id)58 static bool write_uint(SkWStream* stream, size_t n, uint32_t id) {
59 return stream->writePackedUInt(id) &&
60 stream->writePackedUInt(n);
61 }
62
write_scalar(SkWStream * stream,SkScalar n,uint32_t id)63 static bool write_scalar(SkWStream* stream, SkScalar n, uint32_t id) {
64 return stream->writePackedUInt(id) &&
65 stream->writeScalar(n);
66 }
67
read_id(SkStream * stream)68 static size_t SK_WARN_UNUSED_RESULT read_id(SkStream* stream) {
69 size_t i;
70 if (!stream->readPackedUInt(&i)) { return kInvalid; }
71 return i;
72 }
73
74 static constexpr SkScalar usWidths[9] {
75 1, 2, 3, 4, 5, 6, 7, 8, 9
76 };
77 static constexpr SkScalar width_for_usWidth[0x10] = {
78 50,
79 50, 62.5, 75, 87.5, 100, 112.5, 125, 150, 200,
80 200, 200, 200, 200, 200, 200
81 };
82
Deserialize(SkStream * stream,SkFontDescriptor * result)83 bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
84 size_t factoryId;
85 using FactoryIdType = decltype(result->fFactoryId);
86
87 size_t coordinateCount;
88 using CoordinateCountType = decltype(result->fCoordinateCount);
89
90 size_t index;
91 using CollectionIndexType = decltype(result->fCollectionIndex);
92
93 size_t paletteIndex;
94 using PaletteIndexType = decltype(result->fPaletteIndex);
95
96 size_t paletteEntryOverrideCount;
97 using PaletteEntryOverrideCountType = decltype(result->fPaletteEntryOverrideCount);
98
99 size_t paletteEntryOverrideIndex;
100 using PaletteEntryOverrideIndexType = decltype(result->fPaletteEntryOverrides[0].index);
101
102 SkScalar weight = SkFontStyle::kNormal_Weight;
103 SkScalar width = SkFontStyle::kNormal_Width;
104 SkScalar slant = 0;
105 SkScalar italic = 0;
106
107 size_t styleBits;
108 if (!stream->readPackedUInt(&styleBits)) { return false; }
109 weight = ((styleBits >> 16) & 0xFFFF);
110 width = ((styleBits >> 8) & 0x000F)[width_for_usWidth];
111 slant = ((styleBits >> 0) & 0x000F) != SkFontStyle::kUpright_Slant ? 14 : 0;
112 italic = ((styleBits >> 0) & 0x000F) == SkFontStyle::kItalic_Slant ? 1 : 0;
113
114 for (size_t id; (id = read_id(stream)) != kSentinel;) {
115 switch (id) {
116 case kFontFamilyName:
117 if (!read_string(stream, &result->fFamilyName)) { return false; }
118 break;
119 case kFullName:
120 if (!read_string(stream, &result->fFullName)) { return false; }
121 break;
122 case kPostscriptName:
123 if (!read_string(stream, &result->fPostscriptName)) { return false; }
124 break;
125 case kWeight:
126 if (!stream->readScalar(&weight)) { return false; }
127 break;
128 case kWidth:
129 if (!stream->readScalar(&width)) { return false; }
130 break;
131 case kSlant:
132 if (!stream->readScalar(&slant)) { return false; }
133 break;
134 case kItalic:
135 if (!stream->readScalar(&italic)) { return false; }
136 break;
137 case kFontVariation:
138 if (!stream->readPackedUInt(&coordinateCount)) { return false; }
139 if (!SkTFitsIn<CoordinateCountType>(coordinateCount)) { return false; }
140 if (StreamRemainingLengthIsBelow(stream, coordinateCount)) {
141 return false;
142 }
143 result->fCoordinateCount = SkTo<CoordinateCountType>(coordinateCount);
144
145 result->fVariation.reset(coordinateCount);
146 for (size_t i = 0; i < coordinateCount; ++i) {
147 if (!stream->readU32(&result->fVariation[i].axis)) { return false; }
148 if (!stream->readScalar(&result->fVariation[i].value)) { return false; }
149 }
150 break;
151 case kFontIndex:
152 if (!stream->readPackedUInt(&index)) { return false; }
153 if (!SkTFitsIn<CollectionIndexType>(index)) { return false; }
154 result->fCollectionIndex = SkTo<CollectionIndexType>(index);
155 break;
156 case kPaletteIndex:
157 if (!stream->readPackedUInt(&paletteIndex)) { return false; }
158 if (!SkTFitsIn<PaletteIndexType>(paletteIndex)) { return false; }
159 result->fPaletteIndex = SkTo<PaletteIndexType>(paletteIndex);
160 break;
161 case kPaletteEntryOverrides:
162 if (!stream->readPackedUInt(&paletteEntryOverrideCount)) { return false; }
163 if (!SkTFitsIn<PaletteEntryOverrideCountType>(paletteEntryOverrideCount)) {
164 return false;
165 }
166 if (StreamRemainingLengthIsBelow(stream, paletteEntryOverrideCount)) {
167 return false;
168 }
169 result->fPaletteEntryOverrideCount =
170 SkTo<PaletteEntryOverrideCountType>(paletteEntryOverrideCount);
171
172 result->fPaletteEntryOverrides.reset(paletteEntryOverrideCount);
173 for (size_t i = 0; i < paletteEntryOverrideCount; ++i) {
174 if (!stream->readPackedUInt(&paletteEntryOverrideIndex)) { return false; }
175 if (!SkTFitsIn<PaletteEntryOverrideIndexType>(paletteEntryOverrideIndex)) {
176 return false;
177 }
178 result->fPaletteEntryOverrides[i].index =
179 SkTo<PaletteEntryOverrideIndexType>(paletteEntryOverrideIndex);
180 if (!stream->readU32(&result->fPaletteEntryOverrides[i].color)) {
181 return false;
182 }
183 }
184 break;
185 case kFactoryId:
186 if (!stream->readPackedUInt(&factoryId)) { return false; }
187 if (!SkTFitsIn<FactoryIdType>(factoryId)) { return false; }
188 result->fFactoryId = SkTo<FactoryIdType>(factoryId);
189 break;
190 default:
191 SkDEBUGFAIL("Unknown id used by a font descriptor");
192 return false;
193 }
194 }
195
196 SkFontStyle::Slant slantEnum = SkFontStyle::kUpright_Slant;
197 if (slant != 0) { slantEnum = SkFontStyle::kOblique_Slant; }
198 if (0 < italic) { slantEnum = SkFontStyle::kItalic_Slant; }
199 SkFontStyle::Width widthEnum = SkFontStyleWidthForWidthAxisValue(width);
200 result->fStyle = SkFontStyle(SkScalarRoundToInt(weight), widthEnum, slantEnum);
201
202 size_t length;
203 if (!stream->readPackedUInt(&length)) { return false; }
204 if (length > 0) {
205 if (StreamRemainingLengthIsBelow(stream, length)) {
206 return false;
207 }
208 sk_sp<SkData> data(SkData::MakeUninitialized(length));
209 if (stream->read(data->writable_data(), length) != length) {
210 SkDEBUGFAIL("Could not read font data");
211 return false;
212 }
213 result->fStream = SkMemoryStream::Make(std::move(data));
214 }
215 return true;
216 }
217
serialize(SkWStream * stream) const218 void SkFontDescriptor::serialize(SkWStream* stream) const {
219 uint32_t styleBits = (fStyle.weight() << 16) | (fStyle.width() << 8) | (fStyle.slant());
220 stream->writePackedUInt(styleBits);
221
222 write_string(stream, fFamilyName, kFontFamilyName);
223 write_string(stream, fFullName, kFullName);
224 write_string(stream, fPostscriptName, kPostscriptName);
225
226 write_scalar(stream, fStyle.weight(), kWeight);
227 write_scalar(stream, fStyle.width()[width_for_usWidth], kWidth);
228 write_scalar(stream, fStyle.slant() == SkFontStyle::kUpright_Slant ? 0 : 14, kSlant);
229 write_scalar(stream, fStyle.slant() == SkFontStyle::kItalic_Slant ? 1 : 0, kItalic);
230
231 if (fCollectionIndex > 0) {
232 write_uint(stream, fCollectionIndex, kFontIndex);
233 }
234 if (fPaletteIndex > 0) {
235 write_uint(stream, fPaletteIndex, kPaletteIndex);
236 }
237 if (fCoordinateCount > 0) {
238 write_uint(stream, fCoordinateCount, kFontVariation);
239 for (int i = 0; i < fCoordinateCount; ++i) {
240 stream->write32(fVariation[i].axis);
241 stream->writeScalar(fVariation[i].value);
242 }
243 }
244 if (fPaletteEntryOverrideCount > 0) {
245 int nonNegativePaletteOverrideIndexes = 0;
246 for (int i = 0; i < fPaletteEntryOverrideCount; ++i) {
247 if (0 <= fPaletteEntryOverrides[i].index) {
248 ++nonNegativePaletteOverrideIndexes;
249 }
250 }
251 write_uint(stream, nonNegativePaletteOverrideIndexes, kPaletteEntryOverrides);
252 for (int i = 0; i < fPaletteEntryOverrideCount; ++i) {
253 if (0 <= fPaletteEntryOverrides[i].index) {
254 stream->writePackedUInt(fPaletteEntryOverrides[i].index);
255 stream->write32(fPaletteEntryOverrides[i].color);
256 }
257 }
258 }
259
260 write_uint(stream, fFactoryId, kFactoryId);
261
262 stream->writePackedUInt(kSentinel);
263
264 if (fStream) {
265 std::unique_ptr<SkStreamAsset> fontStream = fStream->duplicate();
266 size_t length = fontStream->getLength();
267 stream->writePackedUInt(length);
268 stream->writeStream(fontStream.get(), length);
269 } else {
270 stream->writePackedUInt(0);
271 }
272 }
273
SkFontStyleWidthForWidthAxisValue(SkScalar width)274 SkFontStyle::Width SkFontDescriptor::SkFontStyleWidthForWidthAxisValue(SkScalar width) {
275 int usWidth = SkScalarRoundToInt(SkScalarInterpFunc(width, &width_for_usWidth[1], usWidths, 9));
276 return static_cast<SkFontStyle::Width>(usWidth);
277 }
278