/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkAdvancedTypefaceMetrics.h"
#include "SkDataTable.h"
#include "SkFixed.h"
#include "SkFontDescriptor.h"
#include "SkFontHost_FreeType_common.h"
#include "SkFontMgr.h"
#include "SkFontStyle.h"
#include "SkMakeUnique.h"
#include "SkMath.h"
#include "SkMutex.h"
#include "SkOSFile.h"
#include "SkRefCnt.h"
#include "SkStream.h"
#include "SkString.h"
#include "SkTDArray.h"
#include "SkTemplates.h"
#include "SkTypeface.h"
#include "SkTypefaceCache.h"
#include "SkTypes.h"
#include <fontconfig/fontconfig.h>
#include <string.h>
class SkData;
// FC_POSTSCRIPT_NAME was added with b561ff20 which ended up in 2.10.92
// Ubuntu 12.04 is on 2.8.0, 13.10 is on 2.10.93
// Debian 7 is on 2.9.0, 8 is on 2.11
// OpenSUSE 12.2 is on 2.9.0, 12.3 is on 2.10.2, 13.1 2.11.0
// Fedora 19 is on 2.10.93
#ifndef FC_POSTSCRIPT_NAME
# define FC_POSTSCRIPT_NAME "postscriptname"
#endif
#ifdef SK_DEBUG
# include "SkTLS.h"
#endif
/** Since FontConfig is poorly documented, this gives a high level overview:
*
* FcConfig is a handle to a FontConfig configuration instance. Each 'configuration' is independent
* from any others which may exist. There exists a default global configuration which is created
* and destroyed by FcInit and FcFini, but this default should not normally be used.
* Instead, one should use FcConfigCreate and FcInit* to have a named local state.
*
* FcPatterns are {objectName -> [element]} (maps from object names to a list of elements).
* Each element is some internal data plus an FcValue which is a variant (a union with a type tag).
* Lists of elements are not typed, except by convention. Any collection of FcValues must be
* assumed to be heterogeneous by the code, but the code need not do anything particularly
* interesting if the values go against convention.
*
* Somewhat like DirectWrite, FontConfig supports synthetics through FC_EMBOLDEN and FC_MATRIX.
* Like all synthetic information, such information must be passed with the font data.
*/
namespace {
// Fontconfig is not threadsafe before 2.10.91. Before that, we lock with a global mutex.
// See https://bug.skia.org/1497 for background.
SK_DECLARE_STATIC_MUTEX(gFCMutex);
#ifdef SK_DEBUG
void* CreateThreadFcLocked() { return new bool(false); }
void DeleteThreadFcLocked(void* v) { delete static_cast<bool*>(v); }
# define THREAD_FC_LOCKED \
static_cast<bool*>(SkTLS::Get(CreateThreadFcLocked, DeleteThreadFcLocked))
#endif
class FCLocker {
// Assume FcGetVersion() has always been thread safe.
static void lock() {
if (FcGetVersion() < 21091) {
gFCMutex.acquire();
} else {
SkDEBUGCODE(bool* threadLocked = THREAD_FC_LOCKED);
SkASSERT(false == *threadLocked);
SkDEBUGCODE(*threadLocked = true);
}
}
static void unlock() {
AssertHeld();
if (FcGetVersion() < 21091) {
gFCMutex.release();
} else {
SkDEBUGCODE(*THREAD_FC_LOCKED = false);
}
}
public:
FCLocker() { lock(); }
~FCLocker() { unlock(); }
/** If acquire and release were free, FCLocker would be used around each call into FontConfig.
* Instead a much more granular approach is taken, but this means there are times when the
* mutex is held when it should not be. A Suspend will drop the lock until it is destroyed.
* While a Suspend exists, FontConfig should not be used without re-taking the lock.
*/
struct Suspend {
Suspend() { unlock(); }
~Suspend() { lock(); }
};
static void AssertHeld() { SkDEBUGCODE(
if (FcGetVersion() < 21091) {
gFCMutex.assertHeld();
} else {
SkASSERT(true == *THREAD_FC_LOCKED);
}
) }
};
} // namespace
template<typename T, void (*D)(T*)> void FcTDestroy(T* t) {
FCLocker::AssertHeld();
D(t);
}
template <typename T, T* (*C)(), void (*D)(T*)> class SkAutoFc
: public SkAutoTCallVProc<T, FcTDestroy<T, D> > {
public:
SkAutoFc() : SkAutoTCallVProc<T, FcTDestroy<T, D> >(C()) {
T* obj = this->operator T*();
SkASSERT_RELEASE(nullptr != obj);
}
explicit SkAutoFc(T* obj) : SkAutoTCallVProc<T, FcTDestroy<T, D> >(obj) {}
};
typedef SkAutoFc<FcCharSet, FcCharSetCreate, FcCharSetDestroy> SkAutoFcCharSet;
typedef SkAutoFc<FcConfig, FcConfigCreate, FcConfigDestroy> SkAutoFcConfig;
typedef SkAutoFc<FcFontSet, FcFontSetCreate, FcFontSetDestroy> SkAutoFcFontSet;
typedef SkAutoFc<FcLangSet, FcLangSetCreate, FcLangSetDestroy> SkAutoFcLangSet;
typedef SkAutoFc<FcObjectSet, FcObjectSetCreate, FcObjectSetDestroy> SkAutoFcObjectSet;
typedef SkAutoFc<FcPattern, FcPatternCreate, FcPatternDestroy> SkAutoFcPattern;
static bool get_bool(FcPattern* pattern, const char object[], bool missing = false) {
FcBool value;
if (FcPatternGetBool(pattern, object, 0, &value) != FcResultMatch) {
return missing;
}
return value;
}
static int get_int(FcPattern* pattern, const char object[], int missing) {
int value;
if (FcPatternGetInteger(pattern, object, 0, &value) != FcResultMatch) {
return missing;
}
return value;
}
static const char* get_string(FcPattern* pattern, const char object[], const char* missing = "") {
FcChar8* value;
if (FcPatternGetString(pattern, object, 0, &value) != FcResultMatch) {
return missing;
}
return (const char*)value;
}
static const FcMatrix* get_matrix(FcPattern* pattern, const char object[]) {
FcMatrix* matrix;
if (FcPatternGetMatrix(pattern, object, 0, &matrix) != FcResultMatch) {
return nullptr;
}
return matrix;
}
enum SkWeakReturn {
kIsWeak_WeakReturn,
kIsStrong_WeakReturn,
kNoId_WeakReturn
};
/** Ideally there would exist a call like
* FcResult FcPatternIsWeak(pattern, object, id, FcBool* isWeak);
*
* However, there is no such call and as of Fc 2.11.0 even FcPatternEquals ignores the weak bit.
* Currently, the only reliable way of finding the weak bit is by its effect on matching.
* The weak bit only affects the matching of FC_FAMILY and FC_POSTSCRIPT_NAME object values.
* A element with the weak bit is scored after FC_LANG, without the weak bit is scored before.
* Note that the weak bit is stored on the element, not on the value it holds.
*/
static SkWeakReturn is_weak(FcPattern* pattern, const char object[], int id) {
FCLocker::AssertHeld();
FcResult result;
// Create a copy of the pattern with only the value 'pattern'['object'['id']] in it.
// Internally, FontConfig pattern objects are linked lists, so faster to remove from head.
SkAutoFcObjectSet requestedObjectOnly(FcObjectSetBuild(object, nullptr));
SkAutoFcPattern minimal(FcPatternFilter(pattern, requestedObjectOnly));
FcBool hasId = true;
for (int i = 0; hasId && i < id; ++i) {
hasId = FcPatternRemove(minimal, object, 0);
}
if (!hasId) {
return kNoId_WeakReturn;
}
FcValue value;
result = FcPatternGet(minimal, object, 0, &value);
if (result != FcResultMatch) {
return kNoId_WeakReturn;
}
while (hasId) {
hasId = FcPatternRemove(minimal, object, 1);
}
// Create a font set with two patterns.
// 1. the same 'object' as minimal and a lang object with only 'nomatchlang'.
// 2. a different 'object' from minimal and a lang object with only 'matchlang'.
SkAutoFcFontSet fontSet;
SkAutoFcLangSet strongLangSet;
FcLangSetAdd(strongLangSet, (const FcChar8*)"nomatchlang");
SkAutoFcPattern strong(FcPatternDuplicate(minimal));
FcPatternAddLangSet(strong, FC_LANG, strongLangSet);
SkAutoFcLangSet weakLangSet;
FcLangSetAdd(weakLangSet, (const FcChar8*)"matchlang");
SkAutoFcPattern weak;
FcPatternAddString(weak, object, (const FcChar8*)"nomatchstring");
FcPatternAddLangSet(weak, FC_LANG, weakLangSet);
FcFontSetAdd(fontSet, strong.release());
FcFontSetAdd(fontSet, weak.release());
// Add 'matchlang' to the copy of the pattern.
FcPatternAddLangSet(minimal, FC_LANG, weakLangSet);
// Run a match against the copy of the pattern.
// If the 'id' was weak, then we should match the pattern with 'matchlang'.
// If the 'id' was strong, then we should match the pattern with 'nomatchlang'.
// Note that this config is only used for FcFontRenderPrepare, which we don't even want.
// However, there appears to be no way to match/sort without it.
SkAutoFcConfig config;
FcFontSet* fontSets[1] = { fontSet };
SkAutoFcPattern match(FcFontSetMatch(config, fontSets, SK_ARRAY_COUNT(fontSets),
minimal, &result));
FcLangSet* matchLangSet;
FcPatternGetLangSet(match, FC_LANG, 0, &matchLangSet);
return FcLangEqual == FcLangSetHasLang(matchLangSet, (const FcChar8*)"matchlang")
? kIsWeak_WeakReturn : kIsStrong_WeakReturn;
}
/** Removes weak elements from either FC_FAMILY or FC_POSTSCRIPT_NAME objects in the property.
* This can be quite expensive, and should not be used more than once per font lookup.
* This removes all of the weak elements after the last strong element.
*/
static void remove_weak(FcPattern* pattern, const char object[]) {
FCLocker::AssertHeld();
SkAutoFcObjectSet requestedObjectOnly(FcObjectSetBuild(object, nullptr));
SkAutoFcPattern minimal(FcPatternFilter(pattern, requestedObjectOnly));
int lastStrongId = -1;
int numIds;
SkWeakReturn result;
for (int id = 0; ; ++id) {
result = is_weak(minimal, object, 0);
if (kNoId_WeakReturn == result) {
numIds = id;
break;
}
if (kIsStrong_WeakReturn == result) {
lastStrongId = id;
}
SkAssertResult(FcPatternRemove(minimal, object, 0));
}
// If they were all weak, then leave the pattern alone.
if (lastStrongId < 0) {
return;
}
// Remove everything after the last strong.
for (int id = lastStrongId + 1; id < numIds; ++id) {
SkAssertResult(FcPatternRemove(pattern, object, lastStrongId + 1));
}
}
static int map_range(SkFixed value,
SkFixed old_min, SkFixed old_max,
SkFixed new_min, SkFixed new_max)
{
SkASSERT(old_min < old_max);
SkASSERT(new_min <= new_max);
return new_min + SkMulDiv(value - old_min, new_max - new_min, old_max - old_min);
}
struct MapRanges {
SkFixed old_val;
SkFixed new_val;
};
static SkFixed map_ranges_fixed(SkFixed val, MapRanges const ranges[], int rangesCount) {
// -Inf to [0]
if (val < ranges[0].old_val) {
return ranges[0].new_val;
}
// Linear from [i] to [i+1]
for (int i = 0; i < rangesCount - 1; ++i) {
if (val < ranges[i+1].old_val) {
return map_range(val, ranges[i].old_val, ranges[i+1].old_val,
ranges[i].new_val, ranges[i+1].new_val);
}
}
// From [n] to +Inf
// if (fcweight < Inf)
return ranges[rangesCount-1].new_val;
}
static int map_ranges(int val, MapRanges const ranges[], int rangesCount) {
return SkFixedRoundToInt(map_ranges_fixed(SkIntToFixed(val), ranges, rangesCount));
}
template<int n> struct SkTFixed {
static_assert(-32768 <= n && n <= 32767, "SkTFixed_n_not_in_range");
static const SkFixed value = static_cast<SkFixed>(n << 16);
};
static SkFontStyle skfontstyle_from_fcpattern(FcPattern* pattern) {
typedef SkFontStyle SkFS;
static const MapRanges weightRanges[] = {
{ SkTFixed<FC_WEIGHT_THIN>::value, SkTFixed<SkFS::kThin_Weight>::value },
{ SkTFixed<FC_WEIGHT_EXTRALIGHT>::value, SkTFixed<SkFS::kExtraLight_Weight>::value },
{ SkTFixed<FC_WEIGHT_LIGHT>::value, SkTFixed<SkFS::kLight_Weight>::value },
{ SkTFixed<FC_WEIGHT_REGULAR>::value, SkTFixed<SkFS::kNormal_Weight>::value },
{ SkTFixed<FC_WEIGHT_MEDIUM>::value, SkTFixed<SkFS::kMedium_Weight>::value },
{ SkTFixed<FC_WEIGHT_DEMIBOLD>::value, SkTFixed<SkFS::kSemiBold_Weight>::value },
{ SkTFixed<FC_WEIGHT_BOLD>::value, SkTFixed<SkFS::kBold_Weight>::value },
{ SkTFixed<FC_WEIGHT_EXTRABOLD>::value, SkTFixed<SkFS::kExtraBold_Weight>::value },
{ SkTFixed<FC_WEIGHT_BLACK>::value, SkTFixed<SkFS::kBlack_Weight>::value },
{ SkTFixed<FC_WEIGHT_EXTRABLACK>::value, SkTFixed<SkFS::kExtraBlack_Weight>::value },
};
int weight = map_ranges(get_int(pattern, FC_WEIGHT, FC_WEIGHT_REGULAR),
weightRanges, SK_ARRAY_COUNT(weightRanges));
static const MapRanges widthRanges[] = {
{ SkTFixed<FC_WIDTH_ULTRACONDENSED>::value, SkTFixed<SkFS::kUltraCondensed_Width>::value },
{ SkTFixed<FC_WIDTH_EXTRACONDENSED>::value, SkTFixed<SkFS::kExtraCondensed_Width>::value },
{ SkTFixed<FC_WIDTH_CONDENSED>::value, SkTFixed<SkFS::kCondensed_Width>::value },
{ SkTFixed<FC_WIDTH_SEMICONDENSED>::value, SkTFixed<SkFS::kSemiCondensed_Width>::value },
{ SkTFixed<FC_WIDTH_NORMAL>::value, SkTFixed<SkFS::kNormal_Width>::value },
{ SkTFixed<FC_WIDTH_SEMIEXPANDED>::value, SkTFixed<SkFS::kSemiExpanded_Width>::value },
{ SkTFixed<FC_WIDTH_EXPANDED>::value, SkTFixed<SkFS::kExpanded_Width>::value },
{ SkTFixed<FC_WIDTH_EXTRAEXPANDED>::value, SkTFixed<SkFS::kExtraExpanded_Width>::value },
{ SkTFixed<FC_WIDTH_ULTRAEXPANDED>::value, SkTFixed<SkFS::kUltraExpanded_Width>::value },
};
int width = map_ranges(get_int(pattern, FC_WIDTH, FC_WIDTH_NORMAL),
widthRanges, SK_ARRAY_COUNT(widthRanges));
SkFS::Slant slant = SkFS::kUpright_Slant;
switch (get_int(pattern, FC_SLANT, FC_SLANT_ROMAN)) {
case FC_SLANT_ROMAN: slant = SkFS::kUpright_Slant; break;
case FC_SLANT_ITALIC : slant = SkFS::kItalic_Slant ; break;
case FC_SLANT_OBLIQUE: slant = SkFS::kOblique_Slant; break;
default: SkASSERT(false); break;
}
return SkFontStyle(weight, width, slant);
}
static void fcpattern_from_skfontstyle(SkFontStyle style, FcPattern* pattern) {
FCLocker::AssertHeld();
typedef SkFontStyle SkFS;
static const MapRanges weightRanges[] = {
{ SkTFixed<SkFS::kThin_Weight>::value, SkTFixed<FC_WEIGHT_THIN>::value },
{ SkTFixed<SkFS::kExtraLight_Weight>::value, SkTFixed<FC_WEIGHT_EXTRALIGHT>::value },
{ SkTFixed<SkFS::kLight_Weight>::value, SkTFixed<FC_WEIGHT_LIGHT>::value },
{ SkTFixed<SkFS::kNormal_Weight>::value, SkTFixed<FC_WEIGHT_REGULAR>::value },
{ SkTFixed<SkFS::kMedium_Weight>::value, SkTFixed<FC_WEIGHT_MEDIUM>::value },
{ SkTFixed<SkFS::kSemiBold_Weight>::value, SkTFixed<FC_WEIGHT_DEMIBOLD>::value },
{ SkTFixed<SkFS::kBold_Weight>::value, SkTFixed<FC_WEIGHT_BOLD>::value },
{ SkTFixed<SkFS::kExtraBold_Weight>::value, SkTFixed<FC_WEIGHT_EXTRABOLD>::value },
{ SkTFixed<SkFS::kBlack_Weight>::value, SkTFixed<FC_WEIGHT_BLACK>::value },
{ SkTFixed<SkFS::kExtraBlack_Weight>::value, SkTFixed<FC_WEIGHT_EXTRABLACK>::value },
};
int weight = map_ranges(style.weight(), weightRanges, SK_ARRAY_COUNT(weightRanges));
static const MapRanges widthRanges[] = {
{ SkTFixed<SkFS::kUltraCondensed_Width>::value, SkTFixed<FC_WIDTH_ULTRACONDENSED>::value },
{ SkTFixed<SkFS::kExtraCondensed_Width>::value, SkTFixed<FC_WIDTH_EXTRACONDENSED>::value },
{ SkTFixed<SkFS::kCondensed_Width>::value, SkTFixed<FC_WIDTH_CONDENSED>::value },
{ SkTFixed<SkFS::kSemiCondensed_Width>::value, SkTFixed<FC_WIDTH_SEMICONDENSED>::value },
{ SkTFixed<SkFS::kNormal_Width>::value, SkTFixed<FC_WIDTH_NORMAL>::value },
{ SkTFixed<SkFS::kSemiExpanded_Width>::value, SkTFixed<FC_WIDTH_SEMIEXPANDED>::value },
{ SkTFixed<SkFS::kExpanded_Width>::value, SkTFixed<FC_WIDTH_EXPANDED>::value },
{ SkTFixed<SkFS::kExtraExpanded_Width>::value, SkTFixed<FC_WIDTH_EXTRAEXPANDED>::value },
{ SkTFixed<SkFS::kUltraExpanded_Width>::value, SkTFixed<FC_WIDTH_ULTRAEXPANDED>::value },
};
int width = map_ranges(style.width(), widthRanges, SK_ARRAY_COUNT(widthRanges));
int slant = FC_SLANT_ROMAN;
switch (style.slant()) {
case SkFS::kUpright_Slant: slant = FC_SLANT_ROMAN ; break;
case SkFS::kItalic_Slant : slant = FC_SLANT_ITALIC ; break;
case SkFS::kOblique_Slant: slant = FC_SLANT_OBLIQUE; break;
default: SkASSERT(false); break;
}
FcPatternAddInteger(pattern, FC_WEIGHT, weight);
FcPatternAddInteger(pattern, FC_WIDTH , width);
FcPatternAddInteger(pattern, FC_SLANT , slant);
}
class SkTypeface_stream : public SkTypeface_FreeType {
public:
/** @param data takes ownership of the font data.*/
SkTypeface_stream(std::unique_ptr<SkFontData> data,
SkString familyName, const SkFontStyle& style, bool fixedWidth)
: INHERITED(style, fixedWidth)
, fFamilyName(std::move(familyName))
, fData(std::move(data))
{ }
void onGetFamilyName(SkString* familyName) const override {
*familyName = fFamilyName;
}
void onGetFontDescriptor(SkFontDescriptor* desc, bool* serialize) const override {
*serialize = true;
}
SkStreamAsset* onOpenStream(int* ttcIndex) const override {
*ttcIndex = fData->getIndex();
return fData->getStream()->duplicate().release();
}
std::unique_ptr<SkFontData> onMakeFontData() const override {
return skstd::make_unique<SkFontData>(*fData);
}
private:
SkString fFamilyName;
const std::unique_ptr<const SkFontData> fData;
typedef SkTypeface_FreeType INHERITED;
};
class SkTypeface_fontconfig : public SkTypeface_FreeType {
public:
/** @param pattern takes ownership of the reference. */
static SkTypeface_fontconfig* Create(FcPattern* pattern) {
return new SkTypeface_fontconfig(pattern);
}
mutable SkAutoFcPattern fPattern;
void onGetFamilyName(SkString* familyName) const override {
*familyName = get_string(fPattern, FC_FAMILY);
}
void onGetFontDescriptor(SkFontDescriptor* desc, bool* serialize) const override {
FCLocker lock;
desc->setFamilyName(get_string(fPattern, FC_FAMILY));
desc->setFullName(get_string(fPattern, FC_FULLNAME));
desc->setPostscriptName(get_string(fPattern, FC_POSTSCRIPT_NAME));
desc->setStyle(this->fontStyle());
*serialize = false;
}
SkStreamAsset* onOpenStream(int* ttcIndex) const override {
FCLocker lock;
*ttcIndex = get_int(fPattern, FC_INDEX, 0);
return SkStream::MakeFromFile(get_string(fPattern, FC_FILE)).release();
}
void onFilterRec(SkScalerContextRec* rec) const override {
const FcMatrix* fcMatrix = get_matrix(fPattern, FC_MATRIX);
if (fcMatrix) {
// fPost2x2 is column-major, left handed (y down).
// FcMatrix is column-major, right handed (y up).
SkMatrix fm;
fm.setAll(fcMatrix->xx,-fcMatrix->xy, 0,
-fcMatrix->yx, fcMatrix->yy, 0,
0 , 0 , 1);
SkMatrix sm;
rec->getMatrixFrom2x2(&sm);
sm.preConcat(fm);
rec->fPost2x2[0][0] = sm.getScaleX();
rec->fPost2x2[0][1] = sm.getSkewX();
rec->fPost2x2[1][0] = sm.getSkewY();
rec->fPost2x2[1][1] = sm.getScaleY();
}
if (get_bool(fPattern, FC_EMBOLDEN)) {
rec->fFlags |= SkScalerContext::kEmbolden_Flag;
}
this->INHERITED::onFilterRec(rec);
}
std::unique_ptr<SkAdvancedTypefaceMetrics> onGetAdvancedMetrics() const override {
std::unique_ptr<SkAdvancedTypefaceMetrics> info =
this->INHERITED::onGetAdvancedMetrics();
// Simulated fonts shouldn't be considered to be of the type of their data.
if (get_matrix(fPattern, FC_MATRIX) || get_bool(fPattern, FC_EMBOLDEN)) {
info->fType = SkAdvancedTypefaceMetrics::kOther_Font;
}
return info;
}
~SkTypeface_fontconfig() override {
// Hold the lock while unrefing the pattern.
FCLocker lock;
fPattern.reset();
}
private:
/** @param pattern takes ownership of the reference. */
SkTypeface_fontconfig(FcPattern* pattern)
: INHERITED(skfontstyle_from_fcpattern(pattern),
FC_PROPORTIONAL != get_int(pattern, FC_SPACING, FC_PROPORTIONAL))
, fPattern(pattern)
{ }
typedef SkTypeface_FreeType INHERITED;
};
class SkFontMgr_fontconfig : public SkFontMgr {
mutable SkAutoFcConfig fFC;
sk_sp<SkDataTable> fFamilyNames;
SkTypeface_FreeType::Scanner fScanner;
class StyleSet : public SkFontStyleSet {
public:
/** @param parent does not take ownership of the reference.
* @param fontSet takes ownership of the reference.
*/
StyleSet(const SkFontMgr_fontconfig* parent, FcFontSet* fontSet)
: fFontMgr(SkRef(parent)), fFontSet(fontSet)
{ }
~StyleSet() override {
// Hold the lock while unrefing the font set.
FCLocker lock;
fFontSet.reset();
}
int count() override { return fFontSet->nfont; }
void getStyle(int index, SkFontStyle* style, SkString* styleName) override {
if (index < 0 || fFontSet->nfont <= index) {
return;
}
FCLocker lock;
if (style) {
*style = skfontstyle_from_fcpattern(fFontSet->fonts[index]);
}
if (styleName) {
*styleName = get_string(fFontSet->fonts[index], FC_STYLE);
}
}
SkTypeface* createTypeface(int index) override {
FCLocker lock;
FcPattern* match = fFontSet->fonts[index];
return fFontMgr->createTypefaceFromFcPattern(match);
}
SkTypeface* matchStyle(const SkFontStyle& style) override {
FCLocker lock;
SkAutoFcPattern pattern;
fcpattern_from_skfontstyle(style, pattern);
FcConfigSubstitute(fFontMgr->fFC, pattern, FcMatchPattern);
FcDefaultSubstitute(pattern);
FcResult result;
FcFontSet* fontSets[1] = { fFontSet };
SkAutoFcPattern match(FcFontSetMatch(fFontMgr->fFC,
fontSets, SK_ARRAY_COUNT(fontSets),
pattern, &result));
if (nullptr == match) {
return nullptr;
}
return fFontMgr->createTypefaceFromFcPattern(match);
}
private:
sk_sp<const SkFontMgr_fontconfig> fFontMgr;
SkAutoFcFontSet fFontSet;
};
static bool FindName(const SkTDArray<const char*>& list, const char* str) {
int count = list.count();
for (int i = 0; i < count; ++i) {
if (!strcmp(list[i], str)) {
return true;
}
}
return false;
}
static sk_sp<SkDataTable> GetFamilyNames(FcConfig* fcconfig) {
FCLocker lock;
SkTDArray<const char*> names;
SkTDArray<size_t> sizes;
static const FcSetName fcNameSet[] = { FcSetSystem, FcSetApplication };
for (int setIndex = 0; setIndex < (int)SK_ARRAY_COUNT(fcNameSet); ++setIndex) {
// Return value of FcConfigGetFonts must not be destroyed.
FcFontSet* allFonts(FcConfigGetFonts(fcconfig, fcNameSet[setIndex]));
if (nullptr == allFonts) {
continue;
}
for (int fontIndex = 0; fontIndex < allFonts->nfont; ++fontIndex) {
FcPattern* current = allFonts->fonts[fontIndex];
for (int id = 0; ; ++id) {
FcChar8* fcFamilyName;
FcResult result = FcPatternGetString(current, FC_FAMILY, id, &fcFamilyName);
if (FcResultNoId == result) {
break;
}
if (FcResultMatch != result) {
continue;
}
const char* familyName = reinterpret_cast<const char*>(fcFamilyName);
if (familyName && !FindName(names, familyName)) {
*names.append() = familyName;
*sizes.append() = strlen(familyName) + 1;
}
}
}
}
return SkDataTable::MakeCopyArrays((void const *const *)names.begin(),
sizes.begin(), names.count());
}
static bool FindByFcPattern(SkTypeface* cached, void* ctx) {
SkTypeface_fontconfig* cshFace = static_cast<SkTypeface_fontconfig*>(cached);
FcPattern* ctxPattern = static_cast<FcPattern*>(ctx);
return FcTrue == FcPatternEqual(cshFace->fPattern, ctxPattern);
}
mutable SkMutex fTFCacheMutex;
mutable SkTypefaceCache fTFCache;
/** Creates a typeface using a typeface cache.
* @param pattern a complete pattern from FcFontRenderPrepare.
*/
SkTypeface* createTypefaceFromFcPattern(FcPattern* pattern) const {
FCLocker::AssertHeld();
SkAutoMutexAcquire ama(fTFCacheMutex);
SkTypeface* face = fTFCache.findByProcAndRef(FindByFcPattern, pattern);
if (nullptr == face) {
FcPatternReference(pattern);
face = SkTypeface_fontconfig::Create(pattern);
if (face) {
// Cannot hold the lock when calling add; an evicted typeface may need to lock.
FCLocker::Suspend suspend;
fTFCache.add(face);
}
}
return face;
}
public:
/** Takes control of the reference to 'config'. */
explicit SkFontMgr_fontconfig(FcConfig* config)
: fFC(config ? config : FcInitLoadConfigAndFonts())
, fFamilyNames(GetFamilyNames(fFC)) { }
~SkFontMgr_fontconfig() override {
// Hold the lock while unrefing the config.
FCLocker lock;
fFC.reset();
}
protected:
int onCountFamilies() const override {
return fFamilyNames->count();
}
void onGetFamilyName(int index, SkString* familyName) const override {
familyName->set(fFamilyNames->atStr(index));
}
SkFontStyleSet* onCreateStyleSet(int index) const override {
return this->onMatchFamily(fFamilyNames->atStr(index));
}
/** True if any string object value in the font is the same
* as a string object value in the pattern.
*/
static bool AnyMatching(FcPattern* font, FcPattern* pattern, const char* object) {
FcChar8* fontString;
FcChar8* patternString;
FcResult result;
// Set an arbitrary limit on the number of pattern object values to consider.
// TODO: re-write this to avoid N*M
static const int maxId = 16;
for (int patternId = 0; patternId < maxId; ++patternId) {
result = FcPatternGetString(pattern, object, patternId, &patternString);
if (FcResultNoId == result) {
break;
}
if (FcResultMatch != result) {
continue;
}
for (int fontId = 0; fontId < maxId; ++fontId) {
result = FcPatternGetString(font, object, fontId, &fontString);
if (FcResultNoId == result) {
break;
}
if (FcResultMatch != result) {
continue;
}
if (0 == FcStrCmpIgnoreCase(patternString, fontString)) {
return true;
}
}
}
return false;
}
static bool FontAccessible(FcPattern* font) {
// FontConfig can return fonts which are unreadable.
const char* filename = get_string(font, FC_FILE, nullptr);
if (nullptr == filename) {
return false;
}
return sk_exists(filename, kRead_SkFILE_Flag);
}
static bool FontFamilyNameMatches(FcPattern* font, FcPattern* pattern) {
return AnyMatching(font, pattern, FC_FAMILY);
}
static bool FontContainsCharacter(FcPattern* font, uint32_t character) {
FcResult result;
FcCharSet* matchCharSet;
for (int charSetId = 0; ; ++charSetId) {
result = FcPatternGetCharSet(font, FC_CHARSET, charSetId, &matchCharSet);
if (FcResultNoId == result) {
break;
}
if (FcResultMatch != result) {
continue;
}
if (FcCharSetHasChar(matchCharSet, character)) {
return true;
}
}
return false;
}
SkFontStyleSet* onMatchFamily(const char familyName[]) const override {
if (!familyName) {
return nullptr;
}
FCLocker lock;
SkAutoFcPattern pattern;
FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
FcConfigSubstitute(fFC, pattern, FcMatchPattern);
FcDefaultSubstitute(pattern);
FcPattern* matchPattern;
SkAutoFcPattern strongPattern(nullptr);
if (familyName) {
strongPattern.reset(FcPatternDuplicate(pattern));
remove_weak(strongPattern, FC_FAMILY);
matchPattern = strongPattern;
} else {
matchPattern = pattern;
}
SkAutoFcFontSet matches;
// TODO: Some families have 'duplicates' due to symbolic links.
// The patterns are exactly the same except for the FC_FILE.
// It should be possible to collapse these patterns by normalizing.
static const FcSetName fcNameSet[] = { FcSetSystem, FcSetApplication };
for (int setIndex = 0; setIndex < (int)SK_ARRAY_COUNT(fcNameSet); ++setIndex) {
// Return value of FcConfigGetFonts must not be destroyed.
FcFontSet* allFonts(FcConfigGetFonts(fFC, fcNameSet[setIndex]));
if (nullptr == allFonts) {
continue;
}
for (int fontIndex = 0; fontIndex < allFonts->nfont; ++fontIndex) {
FcPattern* font = allFonts->fonts[fontIndex];
if (FontAccessible(font) && FontFamilyNameMatches(font, matchPattern)) {
FcFontSetAdd(matches, FcFontRenderPrepare(fFC, pattern, font));
}
}
}
return new StyleSet(this, matches.release());
}
virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
const SkFontStyle& style) const override
{
FCLocker lock;
SkAutoFcPattern pattern;
FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
fcpattern_from_skfontstyle(style, pattern);
FcConfigSubstitute(fFC, pattern, FcMatchPattern);
FcDefaultSubstitute(pattern);
// We really want to match strong (prefered) and same (acceptable) only here.
// If a family name was specified, assume that any weak matches after the last strong match
// are weak (default) and ignore them.
// The reason for is that after substitution the pattern for 'sans-serif' looks like
// "wwwwwwwwwwwwwwswww" where there are many weak but preferred names, followed by defaults.
// So it is possible to have weakly matching but preferred names.
// In aliases, bindings are weak by default, so this is easy and common.
// If no family name was specified, we'll probably only get weak matches, but that's ok.
FcPattern* matchPattern;
SkAutoFcPattern strongPattern(nullptr);
if (familyName) {
strongPattern.reset(FcPatternDuplicate(pattern));
remove_weak(strongPattern, FC_FAMILY);
matchPattern = strongPattern;
} else {
matchPattern = pattern;
}
FcResult result;
SkAutoFcPattern font(FcFontMatch(fFC, pattern, &result));
if (nullptr == font || !FontAccessible(font) || !FontFamilyNameMatches(font, matchPattern)) {
return nullptr;
}
return createTypefaceFromFcPattern(font);
}
virtual SkTypeface* onMatchFamilyStyleCharacter(const char familyName[],
const SkFontStyle& style,
const char* bcp47[],
int bcp47Count,
SkUnichar character) const override
{
FCLocker lock;
SkAutoFcPattern pattern;
if (familyName) {
FcValue familyNameValue;
familyNameValue.type = FcTypeString;
familyNameValue.u.s = reinterpret_cast<const FcChar8*>(familyName);
FcPatternAddWeak(pattern, FC_FAMILY, familyNameValue, FcFalse);
}
fcpattern_from_skfontstyle(style, pattern);
SkAutoFcCharSet charSet;
FcCharSetAddChar(charSet, character);
FcPatternAddCharSet(pattern, FC_CHARSET, charSet);
if (bcp47Count > 0) {
SkASSERT(bcp47);
SkAutoFcLangSet langSet;
for (int i = bcp47Count; i --> 0;) {
FcLangSetAdd(langSet, (const FcChar8*)bcp47[i]);
}
FcPatternAddLangSet(pattern, FC_LANG, langSet);
}
FcConfigSubstitute(fFC, pattern, FcMatchPattern);
FcDefaultSubstitute(pattern);
FcResult result;
SkAutoFcPattern font(FcFontMatch(fFC, pattern, &result));
if (nullptr == font || !FontAccessible(font) || !FontContainsCharacter(font, character)) {
return nullptr;
}
return createTypefaceFromFcPattern(font);
}
virtual SkTypeface* onMatchFaceStyle(const SkTypeface* typeface,
const SkFontStyle& style) const override
{
//TODO: should the SkTypeface_fontconfig know its family?
const SkTypeface_fontconfig* fcTypeface =
static_cast<const SkTypeface_fontconfig*>(typeface);
return this->matchFamilyStyle(get_string(fcTypeface->fPattern, FC_FAMILY), style);
}
sk_sp<SkTypeface> onMakeFromStreamIndex(std::unique_ptr<SkStreamAsset> stream,
int ttcIndex) const override {
const size_t length = stream->getLength();
if (length <= 0 || (1u << 30) < length) {
return nullptr;
}
SkString name;
SkFontStyle style;
bool isFixedWidth = false;
if (!fScanner.scanFont(stream.get(), ttcIndex, &name, &style, &isFixedWidth, nullptr)) {
return nullptr;
}
auto data = skstd::make_unique<SkFontData>(std::move(stream), ttcIndex, nullptr, 0);
return sk_sp<SkTypeface>(new SkTypeface_stream(std::move(data), std::move(name),
style, isFixedWidth));
}
sk_sp<SkTypeface> onMakeFromStreamArgs(std::unique_ptr<SkStreamAsset> stream,
const SkFontArguments& args) const override {
using Scanner = SkTypeface_FreeType::Scanner;
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 data = skstd::make_unique<SkFontData>(std::move(stream), args.getCollectionIndex(),
axisValues.get(), axisDefinitions.count());
return sk_sp<SkTypeface>(new SkTypeface_stream(std::move(data), std::move(name),
style, isFixedPitch));
}
sk_sp<SkTypeface> onMakeFromData(sk_sp<SkData> data, int ttcIndex) const override {
return this->makeFromStream(skstd::make_unique<SkMemoryStream>(std::move(data)), ttcIndex);
}
sk_sp<SkTypeface> onMakeFromFile(const char path[], int ttcIndex) const override {
return this->makeFromStream(SkStream::MakeFromFile(path), ttcIndex);
}
sk_sp<SkTypeface> onMakeFromFontData(std::unique_ptr<SkFontData> fontData) const override {
SkStreamAsset* stream(fontData->getStream());
const size_t length = stream->getLength();
if (length <= 0 || (1u << 30) < length) {
return nullptr;
}
const int ttcIndex = fontData->getIndex();
SkString name;
SkFontStyle style;
bool isFixedWidth = false;
if (!fScanner.scanFont(stream, ttcIndex, &name, &style, &isFixedWidth, nullptr)) {
return nullptr;
}
return sk_sp<SkTypeface>(new SkTypeface_stream(std::move(fontData), std::move(name),
style, isFixedWidth));
}
sk_sp<SkTypeface> onLegacyMakeTypeface(const char familyName[], SkFontStyle style) const override {
sk_sp<SkTypeface> typeface(this->matchFamilyStyle(familyName, style));
if (typeface) {
return typeface;
}
return sk_sp<SkTypeface>(this->matchFamilyStyle(nullptr, style));
}
};
SK_API sk_sp<SkFontMgr> SkFontMgr_New_FontConfig(FcConfig* fc) {
return sk_make_sp<SkFontMgr_fontconfig>(fc);
}