1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/modules/font_access/font_metadata.h"
#include <memory>
#include <utility>
#include "base/metrics/histogram_functions.h"
#include "base/numerics/safe_conversions.h"
#include "build/build_config.h"
#include "third_party/blink/renderer/bindings/core/v8/script_promise_resolver.h"
#include "third_party/blink/renderer/core/fileapi/blob.h"
#include "third_party/blink/renderer/platform/bindings/script_state.h"
#include "third_party/blink/renderer/platform/fonts/font_cache.h"
#include "third_party/blink/renderer/platform/fonts/font_global_context.h"
#include "third_party/blink/renderer/platform/fonts/font_unique_name_lookup.h"
#include "third_party/blink/renderer/platform/scheduler/public/thread.h"
#include "third_party/skia/include/core/SkStream.h"
#include "third_party/skia/include/core/SkTypes.h"
namespace blink {
namespace {
// Sets up internal FontUniqueLookup data that will allow matching unique names,
// on platforms that apply.
void SetUpFontUniqueLookupIfNecessary() {
FontUniqueNameLookup* unique_name_lookup =
FontGlobalContext::Get().GetFontUniqueNameLookup();
if (!unique_name_lookup)
return;
// Contrary to what the method name might imply, this is not an idempotent
// method. It also initializes state in the FontUniqueNameLookup object.
unique_name_lookup->IsFontUniqueNameLookupReadyForSyncLookup();
}
} // namespace
FontMetadata::FontMetadata(const FontEnumerationEntry& entry)
: postscriptName_(entry.postscript_name),
fullName_(entry.full_name),
family_(entry.family),
style_(entry.style) {}
FontMetadata* FontMetadata::Create(const FontEnumerationEntry& entry) {
return MakeGarbageCollected<FontMetadata>(entry);
}
ScriptPromise<Blob> FontMetadata::blob(ScriptState* script_state) {
auto* resolver =
MakeGarbageCollected<ScriptPromiseResolver<Blob>>(script_state);
auto promise = resolver->Promise();
ExecutionContext::From(script_state)
->GetTaskRunner(TaskType::kFontLoading)
->PostTask(FROM_HERE,
WTF::BindOnce(&FontMetadata::BlobImpl,
WrapPersistent(resolver), postscriptName_));
return promise;
}
void FontMetadata::Trace(blink::Visitor* visitor) const {
ScriptWrappable::Trace(visitor);
}
// static
void FontMetadata::BlobImpl(ScriptPromiseResolver<Blob>* resolver,
const String& postscriptName) {
if (!resolver->GetScriptState()->ContextIsValid())
return;
SetUpFontUniqueLookupIfNecessary();
FontDescription description;
const SimpleFontData* font_data =
FontCache::Get().GetFontData(description, AtomicString(postscriptName),
AlternateFontName::kLocalUniqueFace);
if (!font_data) {
auto message = String::Format("The font %s could not be accessed.",
postscriptName.Latin1().c_str());
ScriptState::Scope scope(resolver->GetScriptState());
resolver->Reject(V8ThrowException::CreateTypeError(
resolver->GetScriptState()->GetIsolate(), message));
return;
}
const SkTypeface* typeface = font_data->PlatformData().Typeface();
// On Mac, this will not be as efficient as on other platforms: data from
// tables will be copied and assembled into valid SNFT font data. This is
// because Mac system APIs only return per-table data.
int ttc_index = 0;
std::unique_ptr<SkStreamAsset> stream = typeface->openStream(&ttc_index);
if (!(stream && stream->getMemoryBase())) {
// TODO(https://crbug.com/1086840): openStream rarely fails, but it happens
// sometimes. A potential remediation is to synthesize a font from tables
// at the cost of memory and throughput.
auto message = String::Format("Font data for %s could not be accessed.",
postscriptName.Latin1().c_str());
ScriptState::Scope scope(resolver->GetScriptState());
resolver->Reject(V8ThrowException::CreateTypeError(
resolver->GetScriptState()->GetIsolate(), message));
return;
}
wtf_size_t font_byte_size =
base::checked_cast<wtf_size_t>(stream->getLength());
// TODO(https://crbug.com/1069900): This copies the font bytes. Lazy load and
// stream the data instead.
Vector<char> bytes(font_byte_size);
size_t returned_size = stream->read(bytes.data(), font_byte_size);
DCHECK_EQ(returned_size, font_byte_size);
scoped_refptr<RawData> raw_data = RawData::Create();
bytes.swap(*raw_data->MutableData());
auto blob_data = std::make_unique<BlobData>();
blob_data->AppendData(std::move(raw_data));
blob_data->SetContentType("application/octet-stream");
auto* blob = MakeGarbageCollected<Blob>(
BlobDataHandle::Create(std::move(blob_data), font_byte_size));
resolver->Resolve(blob);
}
} // namespace blink
|
