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 "SkFontDescriptor.h"
9#include "SkMakeUnique.h"
10#include "SkStream.h"
11#include "SkData.h"
12
13enum {
14    // these must match the sfnt 'name' enums
15    kFontFamilyName = 0x01,
16    kFullName       = 0x04,
17    kPostscriptName = 0x06,
18
19    // These count backwards from 0xFF, so as not to collide with the SFNT
20    // defines for names in its 'name' table.
21    kFontAxes       = 0xFC,
22    kFontIndex      = 0xFD,
23    kSentinel       = 0xFF,
24};
25
26SkFontDescriptor::SkFontDescriptor() { }
27
28static void read_string(SkStream* stream, SkString* string) {
29    const uint32_t length = SkToU32(stream->readPackedUInt());
30    if (length > 0) {
31        string->resize(length);
32        stream->read(string->writable_str(), length);
33    }
34}
35
36static void write_string(SkWStream* stream, const SkString& string, uint32_t id) {
37    if (!string.isEmpty()) {
38        stream->writePackedUInt(id);
39        stream->writePackedUInt(string.size());
40        stream->write(string.c_str(), string.size());
41    }
42}
43
44static size_t read_uint(SkStream* stream) {
45    return stream->readPackedUInt();
46}
47
48static void write_uint(SkWStream* stream, size_t n, uint32_t id) {
49    stream->writePackedUInt(id);
50    stream->writePackedUInt(n);
51}
52
53bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
54    size_t styleBits = stream->readPackedUInt();
55    result->fStyle = SkFontStyle((styleBits >> 16) & 0xFFFF,
56                                 (styleBits >> 8 ) & 0xFF,
57                                 static_cast<SkFontStyle::Slant>(styleBits & 0xFF));
58
59    SkAutoSTMalloc<4, SkFixed> axis;
60    size_t axisCount = 0;
61    size_t index = 0;
62    for (size_t id; (id = stream->readPackedUInt()) != kSentinel;) {
63        switch (id) {
64            case kFontFamilyName:
65                read_string(stream, &result->fFamilyName);
66                break;
67            case kFullName:
68                read_string(stream, &result->fFullName);
69                break;
70            case kPostscriptName:
71                read_string(stream, &result->fPostscriptName);
72                break;
73            case kFontAxes:
74                axisCount = read_uint(stream);
75                axis.reset(axisCount);
76                for (size_t i = 0; i < axisCount; ++i) {
77                    axis[i] = read_uint(stream);
78                }
79                break;
80            case kFontIndex:
81                index = read_uint(stream);
82                break;
83            default:
84                SkDEBUGFAIL("Unknown id used by a font descriptor");
85                return false;
86        }
87    }
88
89    size_t length = stream->readPackedUInt();
90    if (length > 0) {
91        sk_sp<SkData> data(SkData::MakeUninitialized(length));
92        if (stream->read(data->writable_data(), length) == length) {
93            result->fFontData = skstd::make_unique<SkFontData>(
94                                   SkMemoryStream::Make(std::move(data)), index, axis, axisCount);
95        } else {
96            SkDEBUGFAIL("Could not read font data");
97            return false;
98        }
99    }
100    return true;
101}
102
103void SkFontDescriptor::serialize(SkWStream* stream) {
104    uint32_t styleBits = (fStyle.weight() << 16) | (fStyle.width() << 8) | (fStyle.slant());
105    stream->writePackedUInt(styleBits);
106
107    write_string(stream, fFamilyName, kFontFamilyName);
108    write_string(stream, fFullName, kFullName);
109    write_string(stream, fPostscriptName, kPostscriptName);
110    if (fFontData.get()) {
111        if (fFontData->getIndex()) {
112            write_uint(stream, fFontData->getIndex(), kFontIndex);
113        }
114        if (fFontData->getAxisCount()) {
115            write_uint(stream, fFontData->getAxisCount(), kFontAxes);
116            for (int i = 0; i < fFontData->getAxisCount(); ++i) {
117                stream->writePackedUInt(fFontData->getAxis()[i]);
118            }
119        }
120    }
121
122    stream->writePackedUInt(kSentinel);
123
124    if (fFontData.get() && fFontData->hasStream()) {
125        std::unique_ptr<SkStreamAsset> fontStream = fFontData->detachStream();
126        size_t length = fontStream->getLength();
127        stream->writePackedUInt(length);
128        stream->writeStream(fontStream.get(), length);
129    } else {
130        stream->writePackedUInt(0);
131    }
132}
133