src/fonts/SkFontMgr_fontconfig.cpp - platform/external/skia - Gitiles

 /*
  * 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 "SkFontMgr.h"
 #include "SkFontStyle.h"
 #include "SkFontConfigInterface.h"
 #include "SkFontConfigTypeface.h"
 #include "SkMath.h"
 #include "SkString.h"
 #include "SkTDArray.h"
 #include "SkThread.h"

 // for now we pull these in directly. eventually we will solely rely on the
 // SkFontConfigInterface instance.
 #include <fontconfig/fontconfig.h>
 #include <unistd.h>

 namespace {

 // Fontconfig is not threadsafe before 2.10.91.  Before that, we lock with a global mutex.
 // See skia:1497 for background.
 SK_DECLARE_STATIC_MUTEX(gFCMutex);
 static bool gFCSafeToUse;

 struct FCLocker {
     FCLocker() {
         if (FcGetVersion() < 21091) {  // We assume FcGetVersion() has always been thread safe.
             gFCMutex.acquire();
             fUnlock = true;
         } else {
             fUnlock = false;
         }
         gFCSafeToUse = true;
     }

     ~FCLocker() {
         if (fUnlock) {
             gFCSafeToUse = false;
             gFCMutex.release();
         }
     }

 private:
     bool fUnlock;
 };

 } // namespace

 // borrow this global from SkFontHost_fontconfig. eventually that file should
 // go away, and be replaced with this one.
 extern SkFontConfigInterface* SkFontHost_fontconfig_ref_global();
 static SkFontConfigInterface* RefFCI() {
     return SkFontHost_fontconfig_ref_global();
 }

 // look for the last substring after a '/' and return that, or return null.
 static const char* find_just_name(const char* str) {
     const char* last = strrchr(str, '/');
     return last ? last + 1 : NULL;
 }

 static bool is_lower(char c) {
     return c >= 'a' && c <= 'z';
 }

 static int get_int(FcPattern* pattern, const char field[]) {
     SkASSERT(gFCSafeToUse);
     int value;
     if (FcPatternGetInteger(pattern, field, 0, &value) != FcResultMatch) {
         value = SK_MinS32;
     }
     return value;
 }

 static const char* get_name(FcPattern* pattern, const char field[]) {
     SkASSERT(gFCSafeToUse);
     const char* name;
     if (FcPatternGetString(pattern, field, 0, (FcChar8**)&name) != FcResultMatch) {
         name = "";
     }
     return name;
 }

 static bool valid_pattern(FcPattern* pattern) {
     SkASSERT(gFCSafeToUse);
     FcBool is_scalable;
     if (FcPatternGetBool(pattern, FC_SCALABLE, 0, &is_scalable) != FcResultMatch || !is_scalable) {
         return false;
     }

     // fontconfig can also return fonts which are unreadable
     const char* c_filename = get_name(pattern, FC_FILE);
     if (0 == *c_filename) {
         return false;
     }
     if (access(c_filename, R_OK) != 0) {
         return false;
     }
     return true;
 }

 static bool match_name(FcPattern* pattern, const char family_name[]) {
     return !strcasecmp(family_name, get_name(pattern, FC_FAMILY));
 }

 static FcPattern** MatchFont(FcFontSet* font_set,
                              const char post_config_family[],
                              int* count) {
   // Older versions of fontconfig have a bug where they cannot select
   // only scalable fonts so we have to manually filter the results.

     FcPattern** iter = font_set->fonts;
     FcPattern** stop = iter + font_set->nfont;
     // find the first good match
     for (; iter < stop; ++iter) {
         if (valid_pattern(*iter)) {
             break;
         }
     }

     if (iter == stop || !match_name(*iter, post_config_family)) {
         return NULL;
     }

     FcPattern** firstIter = iter++;
     for (; iter < stop; ++iter) {
         if (!valid_pattern(*iter) || !match_name(*iter, post_config_family)) {
             break;
         }
     }

     *count = iter - firstIter;
     return firstIter;
 }

 class SkFontStyleSet_FC : public SkFontStyleSet {
 public:
     SkFontStyleSet_FC(FcPattern** matches, int count);
     virtual ~SkFontStyleSet_FC();

     int count() SK_OVERRIDE { return fRecCount; }
     void getStyle(int index, SkFontStyle*, SkString* style) SK_OVERRIDE;
     SkTypeface* createTypeface(int index) SK_OVERRIDE;
     SkTypeface* matchStyle(const SkFontStyle& pattern) SK_OVERRIDE;

 private:
     struct Rec {
         SkString    fStyleName;
         SkString    fFileName;
         SkFontStyle fStyle;
     };
     Rec* fRecs;
     int  fRecCount;
 };

 static int map_range(int value,
                      int old_min, int old_max, int new_min, int 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);
 }

 static SkFontStyle make_fontconfig_style(FcPattern* match) {
     int weight = get_int(match, FC_WEIGHT);
     int width = get_int(match, FC_WIDTH);
     int slant = get_int(match, FC_SLANT);
 //    SkDebugf("old weight %d new weight %d\n", weight, map_range(weight, 0, 80, 0, 400));

     // fontconfig weight seems to be 0..200 or so, so we remap it here
     weight = map_range(weight, 0, 80, 0, 400);
     width = map_range(width, 0, 200, 0, 9);
     return SkFontStyle(weight, width, slant > 0 ? SkFontStyle::kItalic_Slant
                                                 : SkFontStyle::kUpright_Slant);
 }

 SkFontStyleSet_FC::SkFontStyleSet_FC(FcPattern** matches, int count) {
     fRecCount = count;
     fRecs = SkNEW_ARRAY(Rec, count);
     for (int i = 0; i < count; ++i) {
         fRecs[i].fStyleName.set(get_name(matches[i], FC_STYLE));
         fRecs[i].fFileName.set(get_name(matches[i], FC_FILE));
         fRecs[i].fStyle = make_fontconfig_style(matches[i]);
     }
 }

 SkFontStyleSet_FC::~SkFontStyleSet_FC() {
     SkDELETE_ARRAY(fRecs);
 }

 void SkFontStyleSet_FC::getStyle(int index, SkFontStyle* style,
                                  SkString* styleName) {
     SkASSERT((unsigned)index < (unsigned)fRecCount);
     if (style) {
         *style = fRecs[index].fStyle;
     }
     if (styleName) {
         *styleName = fRecs[index].fStyleName;
     }
 }

 SkTypeface* SkFontStyleSet_FC::createTypeface(int index) {
     return NULL;
 }

 SkTypeface* SkFontStyleSet_FC::matchStyle(const SkFontStyle& pattern) {
     return NULL;
 }

 class SkFontMgr_fontconfig : public SkFontMgr {
     SkAutoTUnref<SkFontConfigInterface> fFCI;
     SkDataTable* fFamilyNames;
     SkTypeface_FreeType::Scanner fScanner;

 public:
     SkFontMgr_fontconfig(SkFontConfigInterface* fci)
         : fFCI(fci)
         , fFamilyNames(fFCI->getFamilyNames()) {}

     virtual ~SkFontMgr_fontconfig() {
         SkSafeUnref(fFamilyNames);
     }

 protected:
     int onCountFamilies() const SK_OVERRIDE {
         return fFamilyNames->count();
     }

     void onGetFamilyName(int index, SkString* familyName) const SK_OVERRIDE {
         familyName->set(fFamilyNames->atStr(index));
     }

     SkFontStyleSet* onCreateStyleSet(int index) const SK_OVERRIDE {
         return this->onMatchFamily(fFamilyNames->atStr(index));
     }

     SkFontStyleSet* onMatchFamily(const char familyName[]) const SK_OVERRIDE {
         FCLocker lock;

         FcPattern* pattern = FcPatternCreate();

         FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
 #if 0
         FcPatternAddBool(pattern, FC_SCALABLE, FcTrue);
 #endif
         FcConfigSubstitute(NULL, pattern, FcMatchPattern);
         FcDefaultSubstitute(pattern);

         const char* post_config_family = get_name(pattern, FC_FAMILY);

         FcResult result;
         FcFontSet* font_set = FcFontSort(0, pattern, 0, 0, &result);
         if (!font_set) {
             FcPatternDestroy(pattern);
             return NULL;
         }

         int count;
         FcPattern** match = MatchFont(font_set, post_config_family, &count);
         if (!match) {
             FcPatternDestroy(pattern);
             FcFontSetDestroy(font_set);
             return NULL;
         }

         FcPatternDestroy(pattern);

         SkTDArray<FcPattern*> trimmedMatches;
         for (int i = 0; i < count; ++i) {
             const char* justName = find_just_name(get_name(match[i], FC_FILE));
             if (!is_lower(*justName)) {
                 *trimmedMatches.append() = match[i];
             }
         }

         SkFontStyleSet_FC* sset = SkNEW_ARGS(SkFontStyleSet_FC,
                                              (trimmedMatches.begin(),
                                               trimmedMatches.count()));
         return sset;
     }

     virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
                                            const SkFontStyle&) const SK_OVERRIDE { return NULL; }
     virtual SkTypeface* onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
                                                     const char* bcp47[], int bcp47Count,
                                                     SkUnichar character) const SK_OVERRIDE {
         return NULL;
     }
     virtual SkTypeface* onMatchFaceStyle(const SkTypeface*,
                                          const SkFontStyle&) const SK_OVERRIDE { return NULL; }

     SkTypeface* onCreateFromData(SkData*, int ttcIndex) const SK_OVERRIDE { return NULL; }

     SkTypeface* onCreateFromStream(SkStreamAsset* bareStream, int ttcIndex) const SK_OVERRIDE {
         SkAutoTDelete<SkStreamAsset> stream(bareStream);
         const size_t length = stream->getLength();
         if (!length) {
             return NULL;
         }
         if (length >= 1024 * 1024 * 1024) {
             return NULL;  // don't accept too large fonts (>= 1GB) for safety.
         }

         // TODO should the caller give us the style or should we get it from freetype?
         SkFontStyle style;
         bool isFixedWidth = false;
         if (!fScanner.scanFont(stream, 0, NULL, &style, &isFixedWidth)) {
             return NULL;
         }

         SkTypeface* face = FontConfigTypeface::Create(style, isFixedWidth, stream.detach());
         return face;
     }

     SkTypeface* onCreateFromFile(const char path[], int ttcIndex) const SK_OVERRIDE {
         SkAutoTDelete<SkStreamAsset> stream(SkStream::NewFromFile(path));
         return stream.get() ? this->createFromStream(stream.detach(), ttcIndex) : NULL;
     }

     virtual SkTypeface* onLegacyCreateTypeface(const char familyName[],
                                                unsigned styleBits) const SK_OVERRIDE {
         FCLocker lock;
         return FontConfigTypeface::LegacyCreateTypeface(NULL, familyName,
                                                   (SkTypeface::Style)styleBits);
     }
 };

 SkFontMgr* SkFontMgr::Factory() {
     SkFontConfigInterface* fci = RefFCI();
     return fci ? SkNEW_ARGS(SkFontMgr_fontconfig, (fci)) : NULL;
 }
	/*
	* 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 "SkFontMgr.h"
	#include "SkFontStyle.h"
	#include "SkFontConfigInterface.h"
	#include "SkFontConfigTypeface.h"
	#include "SkMath.h"
	#include "SkString.h"
	#include "SkTDArray.h"
	#include "SkThread.h"

	// for now we pull these in directly. eventually we will solely rely on the
	// SkFontConfigInterface instance.
	#include <fontconfig/fontconfig.h>
	#include <unistd.h>

	namespace {

	// Fontconfig is not threadsafe before 2.10.91. Before that, we lock with a global mutex.
	// See skia:1497 for background.
	SK_DECLARE_STATIC_MUTEX(gFCMutex);
	static bool gFCSafeToUse;

	struct FCLocker {
	FCLocker() {
	if (FcGetVersion() < 21091) { // We assume FcGetVersion() has always been thread safe.
	gFCMutex.acquire();
	fUnlock = true;
	} else {
	fUnlock = false;
	}
	gFCSafeToUse = true;
	}

	~FCLocker() {
	if (fUnlock) {
	gFCSafeToUse = false;
	gFCMutex.release();
	}
	}

	private:
	bool fUnlock;
	};

	} // namespace

	// borrow this global from SkFontHost_fontconfig. eventually that file should
	// go away, and be replaced with this one.
	extern SkFontConfigInterface* SkFontHost_fontconfig_ref_global();
	static SkFontConfigInterface* RefFCI() {
	return SkFontHost_fontconfig_ref_global();
	}

	// look for the last substring after a '/' and return that, or return null.
	static const char* find_just_name(const char* str) {
	const char* last = strrchr(str, '/');
	return last ? last + 1 : NULL;
	}

	static bool is_lower(char c) {
	return c >= 'a' && c <= 'z';
	}

	static int get_int(FcPattern* pattern, const char field[]) {
	SkASSERT(gFCSafeToUse);
	int value;
	if (FcPatternGetInteger(pattern, field, 0, &value) != FcResultMatch) {
	value = SK_MinS32;
	}
	return value;
	}

	static const char* get_name(FcPattern* pattern, const char field[]) {
	SkASSERT(gFCSafeToUse);
	const char* name;
	if (FcPatternGetString(pattern, field, 0, (FcChar8**)&name) != FcResultMatch) {
	name = "";
	}
	return name;
	}

	static bool valid_pattern(FcPattern* pattern) {
	SkASSERT(gFCSafeToUse);
	FcBool is_scalable;
	if (FcPatternGetBool(pattern, FC_SCALABLE, 0, &is_scalable) != FcResultMatch \|\| !is_scalable) {
	return false;
	}

	// fontconfig can also return fonts which are unreadable
	const char* c_filename = get_name(pattern, FC_FILE);
	if (0 == *c_filename) {
	return false;
	}
	if (access(c_filename, R_OK) != 0) {
	return false;
	}
	return true;
	}

	static bool match_name(FcPattern* pattern, const char family_name[]) {
	return !strcasecmp(family_name, get_name(pattern, FC_FAMILY));
	}

	static FcPattern** MatchFont(FcFontSet* font_set,
	const char post_config_family[],
	int* count) {
	// Older versions of fontconfig have a bug where they cannot select
	// only scalable fonts so we have to manually filter the results.

	FcPattern** iter = font_set->fonts;
	FcPattern** stop = iter + font_set->nfont;
	// find the first good match
	for (; iter < stop; ++iter) {
	if (valid_pattern(*iter)) {
	break;
	}
	}

	if (iter == stop \|\| !match_name(*iter, post_config_family)) {
	return NULL;
	}

	FcPattern** firstIter = iter++;
	for (; iter < stop; ++iter) {
	if (!valid_pattern(iter) \|\| !match_name(iter, post_config_family)) {
	break;
	}
	}

	*count = iter - firstIter;
	return firstIter;
	}

	class SkFontStyleSet_FC : public SkFontStyleSet {
	public:
	SkFontStyleSet_FC(FcPattern** matches, int count);
	virtual ~SkFontStyleSet_FC();

	int count() SK_OVERRIDE { return fRecCount; }
	void getStyle(int index, SkFontStyle, SkString style) SK_OVERRIDE;
	SkTypeface* createTypeface(int index) SK_OVERRIDE;
	SkTypeface* matchStyle(const SkFontStyle& pattern) SK_OVERRIDE;

	private:
	struct Rec {
	SkString fStyleName;
	SkString fFileName;
	SkFontStyle fStyle;
	};
	Rec* fRecs;
	int fRecCount;
	};

	static int map_range(int value,
	int old_min, int old_max, int new_min, int 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);
	}

	static SkFontStyle make_fontconfig_style(FcPattern* match) {
	int weight = get_int(match, FC_WEIGHT);
	int width = get_int(match, FC_WIDTH);
	int slant = get_int(match, FC_SLANT);
	// SkDebugf("old weight %d new weight %d\n", weight, map_range(weight, 0, 80, 0, 400));

	// fontconfig weight seems to be 0..200 or so, so we remap it here
	weight = map_range(weight, 0, 80, 0, 400);
	width = map_range(width, 0, 200, 0, 9);
	return SkFontStyle(weight, width, slant > 0 ? SkFontStyle::kItalic_Slant
	: SkFontStyle::kUpright_Slant);
	}

	SkFontStyleSet_FC::SkFontStyleSet_FC(FcPattern** matches, int count) {
	fRecCount = count;
	fRecs = SkNEW_ARRAY(Rec, count);
	for (int i = 0; i < count; ++i) {
	fRecs[i].fStyleName.set(get_name(matches[i], FC_STYLE));
	fRecs[i].fFileName.set(get_name(matches[i], FC_FILE));
	fRecs[i].fStyle = make_fontconfig_style(matches[i]);
	}
	}

	SkFontStyleSet_FC::~SkFontStyleSet_FC() {
	SkDELETE_ARRAY(fRecs);
	}

	void SkFontStyleSet_FC::getStyle(int index, SkFontStyle* style,
	SkString* styleName) {
	SkASSERT((unsigned)index < (unsigned)fRecCount);
	if (style) {
	*style = fRecs[index].fStyle;
	}
	if (styleName) {
	*styleName = fRecs[index].fStyleName;
	}
	}

	SkTypeface* SkFontStyleSet_FC::createTypeface(int index) {
	return NULL;
	}

	SkTypeface* SkFontStyleSet_FC::matchStyle(const SkFontStyle& pattern) {
	return NULL;
	}

	class SkFontMgr_fontconfig : public SkFontMgr {
	SkAutoTUnref<SkFontConfigInterface> fFCI;
	SkDataTable* fFamilyNames;
	SkTypeface_FreeType::Scanner fScanner;

	public:
	SkFontMgr_fontconfig(SkFontConfigInterface* fci)
	: fFCI(fci)
	, fFamilyNames(fFCI->getFamilyNames()) {}

	virtual ~SkFontMgr_fontconfig() {
	SkSafeUnref(fFamilyNames);
	}

	protected:
	int onCountFamilies() const SK_OVERRIDE {
	return fFamilyNames->count();
	}

	void onGetFamilyName(int index, SkString* familyName) const SK_OVERRIDE {
	familyName->set(fFamilyNames->atStr(index));
	}

	SkFontStyleSet* onCreateStyleSet(int index) const SK_OVERRIDE {
	return this->onMatchFamily(fFamilyNames->atStr(index));
	}

	SkFontStyleSet* onMatchFamily(const char familyName[]) const SK_OVERRIDE {
	FCLocker lock;

	FcPattern* pattern = FcPatternCreate();

	FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
	#if 0
	FcPatternAddBool(pattern, FC_SCALABLE, FcTrue);
	#endif
	FcConfigSubstitute(NULL, pattern, FcMatchPattern);
	FcDefaultSubstitute(pattern);

	const char* post_config_family = get_name(pattern, FC_FAMILY);

	FcResult result;
	FcFontSet* font_set = FcFontSort(0, pattern, 0, 0, &result);
	if (!font_set) {
	FcPatternDestroy(pattern);
	return NULL;
	}

	int count;
	FcPattern** match = MatchFont(font_set, post_config_family, &count);
	if (!match) {
	FcPatternDestroy(pattern);
	FcFontSetDestroy(font_set);
	return NULL;
	}

	FcPatternDestroy(pattern);

	SkTDArray<FcPattern*> trimmedMatches;
	for (int i = 0; i < count; ++i) {
	const char* justName = find_just_name(get_name(match[i], FC_FILE));
	if (!is_lower(*justName)) {
	*trimmedMatches.append() = match[i];
	}
	}

	SkFontStyleSet_FC* sset = SkNEW_ARGS(SkFontStyleSet_FC,
	(trimmedMatches.begin(),
	trimmedMatches.count()));
	return sset;
	}

	virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
	const SkFontStyle&) const SK_OVERRIDE { return NULL; }
	virtual SkTypeface* onMatchFamilyStyleCharacter(const char familyName[], const SkFontStyle&,
	const char* bcp47[], int bcp47Count,
	SkUnichar character) const SK_OVERRIDE {
	return NULL;
	}
	virtual SkTypeface* onMatchFaceStyle(const SkTypeface*,
	const SkFontStyle&) const SK_OVERRIDE { return NULL; }

	SkTypeface* onCreateFromData(SkData*, int ttcIndex) const SK_OVERRIDE { return NULL; }

	SkTypeface* onCreateFromStream(SkStreamAsset* bareStream, int ttcIndex) const SK_OVERRIDE {
	SkAutoTDelete<SkStreamAsset> stream(bareStream);
	const size_t length = stream->getLength();
	if (!length) {
	return NULL;
	}
	if (length >= 1024 * 1024 * 1024) {
	return NULL; // don't accept too large fonts (>= 1GB) for safety.
	}

	// TODO should the caller give us the style or should we get it from freetype?
	SkFontStyle style;
	bool isFixedWidth = false;
	if (!fScanner.scanFont(stream, 0, NULL, &style, &isFixedWidth)) {
	return NULL;
	}

	SkTypeface* face = FontConfigTypeface::Create(style, isFixedWidth, stream.detach());
	return face;
	}

	SkTypeface* onCreateFromFile(const char path[], int ttcIndex) const SK_OVERRIDE {
	SkAutoTDelete<SkStreamAsset> stream(SkStream::NewFromFile(path));
	return stream.get() ? this->createFromStream(stream.detach(), ttcIndex) : NULL;
	}

	virtual SkTypeface* onLegacyCreateTypeface(const char familyName[],
	unsigned styleBits) const SK_OVERRIDE {
	FCLocker lock;
	return FontConfigTypeface::LegacyCreateTypeface(NULL, familyName,
	(SkTypeface::Style)styleBits);
	}
	};

	SkFontMgr* SkFontMgr::Factory() {
	SkFontConfigInterface* fci = RefFCI();
	return fci ? SkNEW_ARGS(SkFontMgr_fontconfig, (fci)) : NULL;
	}