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    kFontFileName   = 0xFE,  // Remove when MIN_PICTURE_VERSION > 41
24    kSentinel       = 0xFF,
25};
26
27SkFontDescriptor::SkFontDescriptor() { }
28
29static void read_string(SkStream* stream, SkString* string) {
30    const uint32_t length = SkToU32(stream->readPackedUInt());
31    if (length > 0) {
32        string->resize(length);
33        stream->read(string->writable_str(), length);
34    }
35}
36
37// Remove when MIN_PICTURE_VERSION > 41
38static void skip_string(SkStream* stream) {
39    const uint32_t length = SkToU32(stream->readPackedUInt());
40    if (length > 0) {
41        stream->skip(length);
42    }
43}
44
45static void write_string(SkWStream* stream, const SkString& string, uint32_t id) {
46    if (!string.isEmpty()) {
47        stream->writePackedUInt(id);
48        stream->writePackedUInt(string.size());
49        stream->write(string.c_str(), string.size());
50    }
51}
52
53static size_t read_uint(SkStream* stream) {
54    return stream->readPackedUInt();
55}
56
57static void write_uint(SkWStream* stream, size_t n, uint32_t id) {
58    stream->writePackedUInt(id);
59    stream->writePackedUInt(n);
60}
61
62bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
63    size_t styleBits = stream->readPackedUInt();
64    if (styleBits <= 2) {
65        // Remove this branch when MIN_PICTURE_VERSION > 45
66        result->fStyle = SkFontStyle::FromOldStyle(styleBits);
67    } else {
68        result->fStyle = SkFontStyle((styleBits >> 16) & 0xFFFF,
69                                     (styleBits >> 8 ) & 0xFF,
70                                     static_cast<SkFontStyle::Slant>(styleBits & 0xFF));
71    }
72
73    SkAutoSTMalloc<4, SkFixed> axis;
74    size_t axisCount = 0;
75    size_t index = 0;
76    for (size_t id; (id = stream->readPackedUInt()) != kSentinel;) {
77        switch (id) {
78            case kFontFamilyName:
79                read_string(stream, &result->fFamilyName);
80                break;
81            case kFullName:
82                read_string(stream, &result->fFullName);
83                break;
84            case kPostscriptName:
85                read_string(stream, &result->fPostscriptName);
86                break;
87            case kFontAxes:
88                axisCount = read_uint(stream);
89                axis.reset(axisCount);
90                for (size_t i = 0; i < axisCount; ++i) {
91                    axis[i] = read_uint(stream);
92                }
93                break;
94            case kFontIndex:
95                index = read_uint(stream);
96                break;
97            case kFontFileName:  // Remove when MIN_PICTURE_VERSION > 41
98                skip_string(stream);
99                break;
100            default:
101                SkDEBUGFAIL("Unknown id used by a font descriptor");
102                return false;
103        }
104    }
105
106    size_t length = stream->readPackedUInt();
107    if (length > 0) {
108        sk_sp<SkData> data(SkData::MakeUninitialized(length));
109        if (stream->read(data->writable_data(), length) == length) {
110            result->fFontData = skstd::make_unique<SkFontData>(
111                skstd::make_unique<SkMemoryStream>(data), index, axis, axisCount);
112        } else {
113            SkDEBUGFAIL("Could not read font data");
114            return false;
115        }
116    }
117    return true;
118}
119
120void SkFontDescriptor::serialize(SkWStream* stream) {
121    uint32_t styleBits = (fStyle.weight() << 16) | (fStyle.width() << 8) | (fStyle.slant());
122    stream->writePackedUInt(styleBits);
123
124    write_string(stream, fFamilyName, kFontFamilyName);
125    write_string(stream, fFullName, kFullName);
126    write_string(stream, fPostscriptName, kPostscriptName);
127    if (fFontData.get()) {
128        if (fFontData->getIndex()) {
129            write_uint(stream, fFontData->getIndex(), kFontIndex);
130        }
131        if (fFontData->getAxisCount()) {
132            write_uint(stream, fFontData->getAxisCount(), kFontAxes);
133            for (int i = 0; i < fFontData->getAxisCount(); ++i) {
134                stream->writePackedUInt(fFontData->getAxis()[i]);
135            }
136        }
137    }
138
139    stream->writePackedUInt(kSentinel);
140
141    if (fFontData.get() && fFontData->hasStream()) {
142        std::unique_ptr<SkStreamAsset> fontStream = fFontData->detachStream();
143        size_t length = fontStream->getLength();
144        stream->writePackedUInt(length);
145        stream->writeStream(fontStream.get(), length);
146    } else {
147        stream->writePackedUInt(0);
148    }
149}
150