/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkFontConfigInterface.h"
#include "SkFontConfigTypeface.h"
#include "SkFontDescriptor.h"
#include "SkFontMgr.h"
#include "SkFontMgr_FontConfigInterface.h"
#include "SkFontStyle.h"
#include "SkMakeUnique.h"
#include "SkMutex.h"
#include "SkString.h"
#include "SkTypeface.h"
#include "SkTypefaceCache.h"
#include "SkResourceCache.h"
SkStreamAsset* SkTypeface_FCI::onOpenStream(int* ttcIndex) const {
*ttcIndex = this->getIdentity().fTTCIndex;
if (fFontData) {
SkStreamAsset* stream = fFontData->getStream();
if (!stream) {
return nullptr;
}
return stream->duplicate().release();
}
return fFCI->openStream(this->getIdentity());
}
std::unique_ptr<SkFontData> SkTypeface_FCI::onMakeFontData() const {
if (fFontData) {
return skstd::make_unique<SkFontData>(*fFontData);
}
const SkFontConfigInterface::FontIdentity& id = this->getIdentity();
return skstd::make_unique<SkFontData>(std::unique_ptr<SkStreamAsset>(fFCI->openStream(id)),
id.fTTCIndex, nullptr, 0);
}
void SkTypeface_FCI::onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocalStream) const {
SkString name;
this->getFamilyName(&name);
desc->setFamilyName(name.c_str());
desc->setStyle(this->fontStyle());
*isLocalStream = SkToBool(fFontData);
}
///////////////////////////////////////////////////////////////////////////////
class SkFontStyleSet_FCI : public SkFontStyleSet {
public:
SkFontStyleSet_FCI() {}
int count() override { return 0; }
void getStyle(int index, SkFontStyle*, SkString* style) override { SkASSERT(false); }
SkTypeface* createTypeface(int index) override { SkASSERT(false); return nullptr; }
SkTypeface* matchStyle(const SkFontStyle& pattern) override { return nullptr; }
};
///////////////////////////////////////////////////////////////////////////////
class SkFontRequestCache {
public:
struct Request : public SkResourceCache::Key {
private:
Request(const char* name, size_t nameLen, const SkFontStyle& style) : fStyle(style) {
/** Pointer to just after the last field of this class. */
char* content = const_cast<char*>(SkTAfter<const char>(&this->fStyle));
// No holes.
SkASSERT(SkTAddOffset<char>(this, sizeof(SkResourceCache::Key) + keySize) == content);
// Has a size divisible by size of uint32_t.
SkASSERT((content - reinterpret_cast<char*>(this)) % sizeof(uint32_t) == 0);
size_t contentLen = SkAlign4(nameLen);
sk_careful_memcpy(content, name, nameLen);
sk_bzero(content + nameLen, contentLen - nameLen);
this->init(nullptr, 0, keySize + contentLen);
}
const SkFontStyle fStyle;
/** The sum of the sizes of the fields of this class. */
static const size_t keySize = sizeof(fStyle);
public:
static Request* Create(const char* name, const SkFontStyle& style) {
size_t nameLen = name ? strlen(name) : 0;
size_t contentLen = SkAlign4(nameLen);
char* storage = new char[sizeof(Request) + contentLen];
return new (storage) Request(name, nameLen, style);
}
void operator delete(void* storage) {
delete[] reinterpret_cast<char*>(storage);
}
};
private:
struct Result : public SkResourceCache::Rec {
Result(Request* request, SkTypeface* typeface)
: fRequest(request)
, fFace(SkSafeRef(typeface)) {}
Result(Result&&) = default;
Result& operator=(Result&&) = default;
const Key& getKey() const override { return *fRequest; }
size_t bytesUsed() const override { return fRequest->size() + sizeof(fFace); }
const char* getCategory() const override { return "request_cache"; }
SkDiscardableMemory* diagnostic_only_getDiscardable() const override { return nullptr; }
std::unique_ptr<Request> fRequest;
sk_sp<SkTypeface> fFace;
};
SkResourceCache fCachedResults;
public:
SkFontRequestCache(size_t maxSize) : fCachedResults(maxSize) {}
/** Takes ownership of request. It will be deleted when no longer needed. */
void add(SkTypeface* face, Request* request) {
fCachedResults.add(new Result(request, face));
}
/** Does not take ownership of request. */
SkTypeface* findAndRef(Request* request) {
SkTypeface* face = nullptr;
fCachedResults.find(*request, [](const SkResourceCache::Rec& rec, void* context) -> bool {
const Result& result = static_cast<const Result&>(rec);
SkTypeface** face = static_cast<SkTypeface**>(context);
*face = result.fFace.get();
return true;
}, &face);
return SkSafeRef(face);
}
};
///////////////////////////////////////////////////////////////////////////////
static bool find_by_FontIdentity(SkTypeface* cachedTypeface, void* ctx) {
typedef SkFontConfigInterface::FontIdentity FontIdentity;
SkTypeface_FCI* cachedFCTypeface = static_cast<SkTypeface_FCI*>(cachedTypeface);
FontIdentity* identity = static_cast<FontIdentity*>(ctx);
return cachedFCTypeface->getIdentity() == *identity;
}
///////////////////////////////////////////////////////////////////////////////
class SkFontMgr_FCI : public SkFontMgr {
sk_sp<SkFontConfigInterface> fFCI;
SkTypeface_FreeType::Scanner fScanner;
mutable SkMutex fMutex;
mutable SkTypefaceCache fTFCache;
// The value of maxSize here is a compromise between cache hits and cache size.
// See https://crbug.com/424082#63 for reason for current size.
static const size_t kMaxSize = 1 << 15;
mutable SkFontRequestCache fCache;
public:
SkFontMgr_FCI(sk_sp<SkFontConfigInterface> fci)
: fFCI(std::move(fci))
, fCache(kMaxSize)
{}
protected:
int onCountFamilies() const override {
return 0;
}
void onGetFamilyName(int index, SkString* familyName) const override {
SK_ABORT("Not implemented.");
}
SkFontStyleSet* onCreateStyleSet(int index) const override {
SK_ABORT("Not implemented.");
return nullptr;
}
SkFontStyleSet* onMatchFamily(const char familyName[]) const override {
return new SkFontStyleSet_FCI();
}
SkTypeface* onMatchFamilyStyle(const char familyName[],
const SkFontStyle&) const override { return nullptr; }
SkTypeface* onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
const char* bcp47[], int bcp47Count,
SkUnichar character) const override {
return nullptr;
}
SkTypeface* onMatchFaceStyle(const SkTypeface*,
const SkFontStyle&) const override { return nullptr; }
sk_sp<SkTypeface> onMakeFromData(sk_sp<SkData>, int ttcIndex) const override { return nullptr; }
sk_sp<SkTypeface> onMakeFromStreamIndex(std::unique_ptr<SkStreamAsset> stream,
int ttcIndex) const override {
const size_t length = stream->getLength();
if (!length) {
return nullptr;
}
if (length >= 1024 * 1024 * 1024) {
return nullptr; // don't accept too large fonts (>= 1GB) for safety.
}
// TODO should the caller give us the style or should we get it from freetype?
SkString name;
SkFontStyle style;
bool isFixedPitch = false;
if (!fScanner.scanFont(stream.get(), 0, &name, &style, &isFixedPitch, nullptr)) {
return nullptr;
}
auto fontData = skstd::make_unique<SkFontData>(std::move(stream), ttcIndex, nullptr, 0);
return sk_sp<SkTypeface>(SkTypeface_FCI::Create(std::move(fontData), std::move(name),
style, isFixedPitch));
}
sk_sp<SkTypeface> onMakeFromStreamArgs(std::unique_ptr<SkStreamAsset> stream,
const SkFontArguments& args) const override {
using Scanner = SkTypeface_FreeType::Scanner;
const size_t length = stream->getLength();
if (!length) {
return nullptr;
}
if (length >= 1024 * 1024 * 1024) {
return nullptr; // don't accept too large fonts (>= 1GB) for safety.
}
bool isFixedPitch;
SkFontStyle style;
SkString name;
Scanner::AxisDefinitions axisDefinitions;
if (!fScanner.scanFont(stream.get(), args.getCollectionIndex(),
&name, &style, &isFixedPitch, &axisDefinitions))
{
return nullptr;
}
SkAutoSTMalloc<4, SkFixed> axisValues(axisDefinitions.count());
Scanner::computeAxisValues(axisDefinitions, args.getVariationDesignPosition(),
axisValues, name);
auto fontData = skstd::make_unique<SkFontData>(std::move(stream),
args.getCollectionIndex(),
axisValues.get(),
axisDefinitions.count());
return sk_sp<SkTypeface>(SkTypeface_FCI::Create(std::move(fontData), std::move(name),
style, isFixedPitch));
}
sk_sp<SkTypeface> onMakeFromFile(const char path[], int ttcIndex) const override {
std::unique_ptr<SkStreamAsset> stream = SkStream::MakeFromFile(path);
return stream ? this->makeFromStream(std::move(stream), ttcIndex) : nullptr;
}
sk_sp<SkTypeface> onLegacyMakeTypeface(const char requestedFamilyName[],
SkFontStyle requestedStyle) const override
{
SkAutoMutexAcquire ama(fMutex);
// Check if this request is already in the request cache.
using Request = SkFontRequestCache::Request;
std::unique_ptr<Request> request(Request::Create(requestedFamilyName, requestedStyle));
SkTypeface* face = fCache.findAndRef(request.get());
if (face) {
return sk_sp<SkTypeface>(face);
}
SkFontConfigInterface::FontIdentity identity;
SkString outFamilyName;
SkFontStyle outStyle;
if (!fFCI->matchFamilyName(requestedFamilyName, requestedStyle,
&identity, &outFamilyName, &outStyle))
{
return nullptr;
}
// Check if a typeface with this FontIdentity is already in the FontIdentity cache.
face = fTFCache.findByProcAndRef(find_by_FontIdentity, &identity);
if (!face) {
face = SkTypeface_FCI::Create(fFCI, identity, std::move(outFamilyName), outStyle);
// Add this FontIdentity to the FontIdentity cache.
fTFCache.add(face);
}
// Add this request to the request cache.
fCache.add(face, request.release());
return sk_sp<SkTypeface>(face);
}
};
SK_API sk_sp<SkFontMgr> SkFontMgr_New_FCI(sk_sp<SkFontConfigInterface> fci) {
SkASSERT(fci);
return sk_make_sp<SkFontMgr_FCI>(std::move(fci));
}