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 "SkStream.h"
10#include "SkData.h"
11
12enum {
13    // these must match the sfnt 'name' enums
14    kFontFamilyName = 0x01,
15    kFullName       = 0x04,
16    kPostscriptName = 0x06,
17
18    // These count backwards from 0xFF, so as not to collide with the SFNT
19    // defines for names in its 'name' table.
20    kFontAxes       = 0xFC,
21    kFontIndex      = 0xFD,
22    kFontFileName   = 0xFE,  // Remove when MIN_PICTURE_VERSION > 41
23    kSentinel       = 0xFF,
24};
25
26SkFontDescriptor::SkFontDescriptor(SkTypeface::Style style) : fStyle(style) { }
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
36// Remove when MIN_PICTURE_VERSION > 41
37static void skip_string(SkStream* stream) {
38    const uint32_t length = SkToU32(stream->readPackedUInt());
39    if (length > 0) {
40        stream->skip(length);
41    }
42}
43
44static void write_string(SkWStream* stream, const SkString& string, uint32_t id) {
45    if (!string.isEmpty()) {
46        stream->writePackedUInt(id);
47        stream->writePackedUInt(string.size());
48        stream->write(string.c_str(), string.size());
49    }
50}
51
52static size_t read_uint(SkStream* stream) {
53    return stream->readPackedUInt();
54}
55
56static void write_uint(SkWStream* stream, size_t n, uint32_t id) {
57    stream->writePackedUInt(id);
58    stream->writePackedUInt(n);
59}
60
61bool SkFontDescriptor::Deserialize(SkStream* stream, SkFontDescriptor* result) {
62    result->fStyle = (SkTypeface::Style)stream->readPackedUInt();
63
64    SkAutoSTMalloc<4, SkFixed> axis;
65    size_t axisCount = 0;
66    size_t index = 0;
67    for (size_t id; (id = stream->readPackedUInt()) != kSentinel;) {
68        switch (id) {
69            case kFontFamilyName:
70                read_string(stream, &result->fFamilyName);
71                break;
72            case kFullName:
73                read_string(stream, &result->fFullName);
74                break;
75            case kPostscriptName:
76                read_string(stream, &result->fPostscriptName);
77                break;
78            case kFontAxes:
79                axisCount = read_uint(stream);
80                axis.reset(axisCount);
81                for (size_t i = 0; i < axisCount; ++i) {
82                    axis[i] = read_uint(stream);
83                }
84                break;
85            case kFontIndex:
86                index = read_uint(stream);
87                break;
88            case kFontFileName:  // Remove when MIN_PICTURE_VERSION > 41
89                skip_string(stream);
90                break;
91            default:
92                SkDEBUGFAIL("Unknown id used by a font descriptor");
93                return false;
94        }
95    }
96
97    size_t length = stream->readPackedUInt();
98    if (length > 0) {
99        SkAutoTUnref<SkData> data(SkData::NewUninitialized(length));
100        if (stream->read(data->writable_data(), length) == length) {
101            result->fFontData.reset(new SkFontData(new SkMemoryStream(data),
102                                                   index, axis, axisCount));
103        } else {
104            SkDEBUGFAIL("Could not read font data");
105            return false;
106        }
107    }
108    return true;
109}
110
111void SkFontDescriptor::serialize(SkWStream* stream) {
112    stream->writePackedUInt(fStyle);
113
114    write_string(stream, fFamilyName, kFontFamilyName);
115    write_string(stream, fFullName, kFullName);
116    write_string(stream, fPostscriptName, kPostscriptName);
117    if (fFontData.get()) {
118        if (fFontData->getIndex()) {
119            write_uint(stream, fFontData->getIndex(), kFontIndex);
120        }
121        if (fFontData->getAxisCount()) {
122            write_uint(stream, fFontData->getAxisCount(), kFontAxes);
123            for (int i = 0; i < fFontData->getAxisCount(); ++i) {
124                stream->writePackedUInt(fFontData->getAxis()[i]);
125            }
126        }
127    }
128
129    stream->writePackedUInt(kSentinel);
130
131    if (fFontData.get() && fFontData->hasStream()) {
132        SkAutoTDelete<SkStreamAsset> fontData(fFontData->detachStream());
133        size_t length = fontData->getLength();
134        stream->writePackedUInt(length);
135        stream->writeStream(fontData, length);
136    } else {
137        stream->writePackedUInt(0);
138    }
139}
140