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
12 enum {
13 kInvalid = 0x00,
14
15 // these must match the sfnt 'name' enums
16 kFontFamilyName = 0x01,
17 kFullName = 0x04,
18 kPostscriptName = 0x06,
19
20 // These count backwards from 0xFF, so as not to collide with the SFNT
21 // defines for names in its 'name' table.
22 kFontVariation = 0xFA,
23 kFontIndex = 0xFD,
24 kSentinel = 0xFF,
25 };
26
SkFontDescriptor()27 SkFontDescriptor::SkFontDescriptor() { }
28
read_string(SkStream * stream,SkString * string)29 static bool SK_WARN_UNUSED_RESULT read_string(SkStream* stream, SkString* string) {
30 size_t length;
31 if (!stream->readPackedUInt(&length)) { return false; }
32 if (length > 0) {
33 string->resize(length);
34 if (stream->read(string->writable_str(), length) != length) { return false; }
35 }
36 return true;
37 }
38
write_string(SkWStream * stream,const SkString & string,uint32_t id)39 static bool write_string(SkWStream* stream, const SkString& string, uint32_t id) {
40 if (string.isEmpty()) { return true; }
41 return stream->writePackedUInt(id) &&
42 stream->writePackedUInt(string.size()) &&
43 stream->write(string.c_str(), string.size());
44 }
45
write_uint(SkWStream * stream,size_t n,uint32_t id)46 static bool write_uint(SkWStream* stream, size_t n, uint32_t id) {
47 return stream->writePackedUInt(id) &&
48 stream->writePackedUInt(n);
49 }
50
read_id(SkStream * stream)51 static size_t SK_WARN_UNUSED_RESULT read_id(SkStream* stream) {
52 size_t i;
53 if (!stream->readPackedUInt(&i)) { return kInvalid; }
54 return i;
55 }
56
Deserialize(SkStream * stream,SkFontDescriptor * result)57 bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
58 size_t styleBits;
59 if (!stream->readPackedUInt(&styleBits)) { return false; }
60 result->fStyle = SkFontStyle((styleBits >> 16) & 0xFFFF,
61 (styleBits >> 8 ) & 0xFF,
62 static_cast<SkFontStyle::Slant>(styleBits & 0xFF));
63
64 size_t coordinateCount;
65 using CoordinateCountType = decltype(result->fCoordinateCount);
66
67 size_t index;
68 using CollectionIndexType = decltype(result->fCollectionIndex);
69
70 for (size_t id; (id = read_id(stream)) != kSentinel;) {
71 switch (id) {
72 case kFontFamilyName:
73 if (!read_string(stream, &result->fFamilyName)) { return false; }
74 break;
75 case kFullName:
76 if (!read_string(stream, &result->fFullName)) { return false; }
77 break;
78 case kPostscriptName:
79 if (!read_string(stream, &result->fPostscriptName)) { return false; }
80 break;
81 case kFontVariation:
82 if (!stream->readPackedUInt(&coordinateCount)) { return false; }
83 if (!SkTFitsIn<CoordinateCountType>(coordinateCount)) { return false; }
84 result->fCoordinateCount = SkTo<CoordinateCountType>(coordinateCount);
85
86 result->fVariation.reset(coordinateCount);
87 for (size_t i = 0; i < coordinateCount; ++i) {
88 if (!stream->readU32(&result->fVariation[i].axis)) { return false; }
89 if (!stream->readScalar(&result->fVariation[i].value)) { return false; }
90 }
91 break;
92 case kFontIndex:
93 if (!stream->readPackedUInt(&index)) { return false; }
94 if (!SkTFitsIn<CollectionIndexType>(index)) { return false; }
95 result->fCollectionIndex = SkTo<CollectionIndexType>(index);
96 break;
97 default:
98 SkDEBUGFAIL("Unknown id used by a font descriptor");
99 return false;
100 }
101 }
102
103 size_t length;
104 if (!stream->readPackedUInt(&length)) { return false; }
105 if (length > 0) {
106 sk_sp<SkData> data(SkData::MakeUninitialized(length));
107 if (stream->read(data->writable_data(), length) != length) {
108 SkDEBUGFAIL("Could not read font data");
109 return false;
110 }
111 result->fStream = SkMemoryStream::Make(std::move(data));
112 }
113 return true;
114 }
115
serialize(SkWStream * stream) const116 void SkFontDescriptor::serialize(SkWStream* stream) const {
117 uint32_t styleBits = (fStyle.weight() << 16) | (fStyle.width() << 8) | (fStyle.slant());
118 stream->writePackedUInt(styleBits);
119
120 write_string(stream, fFamilyName, kFontFamilyName);
121 write_string(stream, fFullName, kFullName);
122 write_string(stream, fPostscriptName, kPostscriptName);
123
124 if (fCollectionIndex) {
125 write_uint(stream, fCollectionIndex, kFontIndex);
126 }
127 if (fCoordinateCount) {
128 write_uint(stream, fCoordinateCount, kFontVariation);
129 for (int i = 0; i < fCoordinateCount; ++i) {
130 stream->write32(fVariation[i].axis);
131 stream->writeScalar(fVariation[i].value);
132 }
133 }
134
135 stream->writePackedUInt(kSentinel);
136
137 if (fStream) {
138 std::unique_ptr<SkStreamAsset> fontStream = fStream->duplicate();
139 size_t length = fontStream->getLength();
140 stream->writePackedUInt(length);
141 stream->writeStream(fontStream.get(), length);
142 } else {
143 stream->writePackedUInt(0);
144 }
145 }
146