blob: cda46a71a9a39d2081a08930d0f146a37739a6d3 [file] [log] [blame]
/*
* Copyright 2009 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* migrated from chrome/src/skia/ext/SkFontHost_fontconfig_direct.cpp */
#include <string>
#include <unistd.h>
#include <fcntl.h>
#include <fontconfig/fontconfig.h>
#include "SkFontConfigInterface.h"
#include "SkStream.h"
class SkFontConfigInterfaceDirect : public SkFontConfigInterface {
public:
SkFontConfigInterfaceDirect();
virtual ~SkFontConfigInterfaceDirect();
virtual bool matchFamilyName(const char familyName[],
SkTypeface::Style requested,
FontIdentity* outFontIdentifier,
SkString* outFamilyName,
SkTypeface::Style* outStyle) SK_OVERRIDE;
virtual SkStream* openStream(const FontIdentity&) SK_OVERRIDE;
private:
SkMutex mutex_;
};
SkFontConfigInterface* SkFontConfigInterface::GetSingletonDirectInterface() {
static SkFontConfigInterface* gDirect;
if (NULL == gDirect) {
gDirect = new SkFontConfigInterfaceDirect;
}
return gDirect;
}
int SkFontConfigInterface::countFamilies() { return 0; }
int SkFontConfigInterface::getFamilySet(int index, SkString* outFamilyName,
FontIdentity outIdentities[],
int maxCount) {
return 0;
}
int SkFontConfigInterface::matchFamilySet(const char familyName[],
SkString* outFamilyName,
FontIdentity outIdentities[],
int maxCount) {
return 0;
}
///////////////////////////////////////////////////////////////////////////////
namespace {
// Equivalence classes, used to match the Liberation and other fonts
// with their metric-compatible replacements. See the discussion in
// GetFontEquivClass().
enum FontEquivClass
{
OTHER,
SANS,
SERIF,
MONO,
SYMBOL,
PGOTHIC,
GOTHIC,
PMINCHO,
MINCHO,
SIMSUN,
NSIMSUN,
SIMHEI,
PMINGLIU,
MINGLIU,
PMINGLIUHK,
MINGLIUHK,
CAMBRIA,
};
// Match the font name against a whilelist of fonts, returning the equivalence
// class.
FontEquivClass GetFontEquivClass(const char* fontname)
{
// It would be nice for fontconfig to tell us whether a given suggested
// replacement is a "strong" match (that is, an equivalent font) or
// a "weak" match (that is, fontconfig's next-best attempt at finding a
// substitute). However, I played around with the fontconfig API for
// a good few hours and could not make it reveal this information.
//
// So instead, we hardcode. Initially this function emulated
// /etc/fonts/conf.d/30-metric-aliases.conf
// from my Ubuntu system, but we're better off being very conservative.
// Arimo, Tinos and Cousine are a set of fonts metric-compatible with
// Arial, Times New Roman and Courier New with a character repertoire
// much larger than Liberation. Note that Cousine is metrically
// compatible with Courier New, but the former is sans-serif while
// the latter is serif.
struct FontEquivMap {
FontEquivClass clazz;
const char name[40];
};
static const FontEquivMap kFontEquivMap[] = {
{ SANS, "Arial" },
{ SANS, "Arimo" },
{ SANS, "Liberation Sans" },
{ SERIF, "Times New Roman" },
{ SERIF, "Tinos" },
{ SERIF, "Liberation Serif" },
{ MONO, "Courier New" },
{ MONO, "Cousine" },
{ MONO, "Liberation Mono" },
{ SYMBOL, "Symbol" },
{ SYMBOL, "Symbol Neu" },
// MS Pゴシック
{ PGOTHIC, "MS PGothic" },
{ PGOTHIC, "\xef\xbc\xad\xef\xbc\xb3 \xef\xbc\xb0"
"\xe3\x82\xb4\xe3\x82\xb7\xe3\x83\x83\xe3\x82\xaf" },
{ PGOTHIC, "IPAPGothic" },
{ PGOTHIC, "MotoyaG04Gothic" },
// MS ゴシック
{ GOTHIC, "MS Gothic" },
{ GOTHIC, "\xef\xbc\xad\xef\xbc\xb3 "
"\xe3\x82\xb4\xe3\x82\xb7\xe3\x83\x83\xe3\x82\xaf" },
{ GOTHIC, "IPAGothic" },
{ GOTHIC, "MotoyaG04GothicMono" },
// MS P明朝
{ PMINCHO, "MS PMincho" },
{ PMINCHO, "\xef\xbc\xad\xef\xbc\xb3 \xef\xbc\xb0"
"\xe6\x98\x8e\xe6\x9c\x9d"},
{ PMINCHO, "IPAPMincho" },
{ PMINCHO, "MotoyaG04Mincho" },
// MS 明朝
{ MINCHO, "MS Mincho" },
{ MINCHO, "\xef\xbc\xad\xef\xbc\xb3 \xe6\x98\x8e\xe6\x9c\x9d" },
{ MINCHO, "IPAMincho" },
{ MINCHO, "MotoyaG04MinchoMono" },
// 宋体
{ SIMSUN, "Simsun" },
{ SIMSUN, "\xe5\xae\x8b\xe4\xbd\x93" },
{ SIMSUN, "MSung GB18030" },
{ SIMSUN, "Song ASC" },
// 新宋体
{ NSIMSUN, "NSimsun" },
{ NSIMSUN, "\xe6\x96\xb0\xe5\xae\x8b\xe4\xbd\x93" },
{ NSIMSUN, "MSung GB18030" },
{ NSIMSUN, "N Song ASC" },
// 黑体
{ SIMHEI, "Simhei" },
{ SIMHEI, "\xe9\xbb\x91\xe4\xbd\x93" },
{ SIMHEI, "MYingHeiGB18030" },
{ SIMHEI, "MYingHeiB5HK" },
// 新細明體
{ PMINGLIU, "PMingLiU"},
{ PMINGLIU, "\xe6\x96\xb0\xe7\xb4\xb0\xe6\x98\x8e\xe9\xab\x94" },
{ PMINGLIU, "MSung B5HK"},
// 細明體
{ MINGLIU, "MingLiU"},
{ MINGLIU, "\xe7\xb4\xb0\xe6\x98\x8e\xe9\xab\x94" },
{ MINGLIU, "MSung B5HK"},
// 新細明體
{ PMINGLIUHK, "PMingLiU_HKSCS"},
{ PMINGLIUHK, "\xe6\x96\xb0\xe7\xb4\xb0\xe6\x98\x8e\xe9\xab\x94_HKSCS" },
{ PMINGLIUHK, "MSung B5HK"},
// 細明體
{ MINGLIUHK, "MingLiU_HKSCS"},
{ MINGLIUHK, "\xe7\xb4\xb0\xe6\x98\x8e\xe9\xab\x94_HKSCS" },
{ MINGLIUHK, "MSung B5HK"},
// Cambria
{ CAMBRIA, "Cambria" },
{ CAMBRIA, "Caladea" },
};
static const size_t kFontCount =
sizeof(kFontEquivMap)/sizeof(kFontEquivMap[0]);
// TODO(jungshik): If this loop turns out to be hot, turn
// the array to a static (hash)map to speed it up.
for (size_t i = 0; i < kFontCount; ++i) {
if (strcasecmp(kFontEquivMap[i].name, fontname) == 0)
return kFontEquivMap[i].clazz;
}
return OTHER;
}
// Return true if |font_a| and |font_b| are visually and at the metrics
// level interchangeable.
bool IsMetricCompatibleReplacement(const char* font_a, const char* font_b)
{
FontEquivClass class_a = GetFontEquivClass(font_a);
FontEquivClass class_b = GetFontEquivClass(font_b);
return class_a != OTHER && class_a == class_b;
}
// Normally we only return exactly the font asked for. In last-resort
// cases, the request either doesn't specify a font or is one of the
// basic font names like "Sans", "Serif" or "Monospace". This function
// tells you whether a given request is for such a fallback.
bool IsFallbackFontAllowed(const std::string& family) {
const char* family_cstr = family.c_str();
return family.empty() ||
strcasecmp(family_cstr, "sans") == 0 ||
strcasecmp(family_cstr, "serif") == 0 ||
strcasecmp(family_cstr, "monospace") == 0;
}
// Find matching font from |font_set| for the given font family.
FcPattern* MatchFont(FcFontSet* font_set,
FcChar8* post_config_family,
const std::string& family) {
// Older versions of fontconfig have a bug where they cannot select
// only scalable fonts so we have to manually filter the results.
FcPattern* match = NULL;
for (int i = 0; i < font_set->nfont; ++i) {
FcPattern* current = font_set->fonts[i];
FcBool is_scalable;
if (FcPatternGetBool(current, FC_SCALABLE, 0,
&is_scalable) != FcResultMatch ||
!is_scalable) {
continue;
}
// fontconfig can also return fonts which are unreadable
FcChar8* c_filename;
if (FcPatternGetString(current, FC_FILE, 0, &c_filename) != FcResultMatch)
continue;
if (access(reinterpret_cast<char*>(c_filename), R_OK) != 0)
continue;
match = current;
break;
}
if (match && !IsFallbackFontAllowed(family)) {
bool acceptable_substitute = false;
for (int id = 0; id < 255; ++id) {
FcChar8* post_match_family;
if (FcPatternGetString(match, FC_FAMILY, id, &post_match_family) !=
FcResultMatch)
break;
acceptable_substitute =
(strcasecmp(reinterpret_cast<char*>(post_config_family),
reinterpret_cast<char*>(post_match_family)) == 0 ||
// Workaround for Issue 12530:
// requested family: "Bitstream Vera Sans"
// post_config_family: "Arial"
// post_match_family: "Bitstream Vera Sans"
// -> We should treat this case as a good match.
strcasecmp(family.c_str(),
reinterpret_cast<char*>(post_match_family)) == 0) ||
IsMetricCompatibleReplacement(family.c_str(),
reinterpret_cast<char*>(post_match_family));
if (acceptable_substitute)
break;
}
if (!acceptable_substitute)
return NULL;
}
return match;
}
// Retrieves |is_bold|, |is_italic| and |font_family| properties from |font|.
SkTypeface::Style GetFontStyle(FcPattern* font) {
int resulting_bold;
if (FcPatternGetInteger(font, FC_WEIGHT, 0, &resulting_bold))
resulting_bold = FC_WEIGHT_NORMAL;
int resulting_italic;
if (FcPatternGetInteger(font, FC_SLANT, 0, &resulting_italic))
resulting_italic = FC_SLANT_ROMAN;
// If we ask for an italic font, fontconfig might take a roman font and set
// the undocumented property FC_MATRIX to a skew matrix. It'll then say
// that the font is italic or oblique. So, if we see a matrix, we don't
// believe that it's italic.
FcValue matrix;
const bool have_matrix = FcPatternGet(font, FC_MATRIX, 0, &matrix) == 0;
// If we ask for an italic font, fontconfig might take a roman font and set
// FC_EMBOLDEN.
FcValue embolden;
const bool have_embolden = FcPatternGet(font, FC_EMBOLDEN, 0, &embolden) == 0;
int styleBits = 0;
if (resulting_bold > FC_WEIGHT_MEDIUM && !have_embolden) {
styleBits |= SkTypeface::kBold;
}
if (resulting_italic > FC_SLANT_ROMAN && !have_matrix) {
styleBits |= SkTypeface::kItalic;
}
return (SkTypeface::Style)styleBits;
}
} // anonymous namespace
///////////////////////////////////////////////////////////////////////////////
#define kMaxFontFamilyLength 2048
SkFontConfigInterfaceDirect::SkFontConfigInterfaceDirect() {
FcInit();
}
SkFontConfigInterfaceDirect::~SkFontConfigInterfaceDirect() {
}
bool SkFontConfigInterfaceDirect::matchFamilyName(const char familyName[],
SkTypeface::Style style,
FontIdentity* outIdentity,
SkString* outFamilyName,
SkTypeface::Style* outStyle) {
std::string familyStr(familyName ? familyName : "");
if (familyStr.length() > kMaxFontFamilyLength) {
return false;
}
SkAutoMutexAcquire ac(mutex_);
FcPattern* pattern = FcPatternCreate();
if (familyName) {
FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
}
FcPatternAddInteger(pattern, FC_WEIGHT,
(style & SkTypeface::kBold) ? FC_WEIGHT_BOLD
: FC_WEIGHT_NORMAL);
FcPatternAddInteger(pattern, FC_SLANT,
(style & SkTypeface::kItalic) ? FC_SLANT_ITALIC
: FC_SLANT_ROMAN);
FcPatternAddBool(pattern, FC_SCALABLE, FcTrue);
FcConfigSubstitute(NULL, pattern, FcMatchPattern);
FcDefaultSubstitute(pattern);
// Font matching:
// CSS often specifies a fallback list of families:
// font-family: a, b, c, serif;
// However, fontconfig will always do its best to find *a* font when asked
// for something so we need a way to tell if the match which it has found is
// "good enough" for us. Otherwise, we can return NULL which gets piped up
// and lets WebKit know to try the next CSS family name. However, fontconfig
// configs allow substitutions (mapping "Arial -> Helvetica" etc) and we
// wish to support that.
//
// Thus, if a specific family is requested we set @family_requested. Then we
// record two strings: the family name after config processing and the
// family name after resolving. If the two are equal, it's a good match.
//
// So consider the case where a user has mapped Arial to Helvetica in their
// config.
// requested family: "Arial"
// post_config_family: "Helvetica"
// post_match_family: "Helvetica"
// -> good match
//
// and for a missing font:
// requested family: "Monaco"
// post_config_family: "Monaco"
// post_match_family: "Times New Roman"
// -> BAD match
//
// However, we special-case fallback fonts; see IsFallbackFontAllowed().
FcChar8* post_config_family;
FcPatternGetString(pattern, FC_FAMILY, 0, &post_config_family);
FcResult result;
FcFontSet* font_set = FcFontSort(0, pattern, 0, 0, &result);
if (!font_set) {
FcPatternDestroy(pattern);
return false;
}
FcPattern* match = MatchFont(font_set, post_config_family, familyStr);
if (!match) {
FcPatternDestroy(pattern);
FcFontSetDestroy(font_set);
return false;
}
FcPatternDestroy(pattern);
// From here out we just extract our results from 'match'
if (FcPatternGetString(match, FC_FAMILY, 0, &post_config_family) != FcResultMatch) {
FcFontSetDestroy(font_set);
return false;
}
FcChar8* c_filename;
if (FcPatternGetString(match, FC_FILE, 0, &c_filename) != FcResultMatch) {
FcFontSetDestroy(font_set);
return false;
}
int face_index;
if (FcPatternGetInteger(match, FC_INDEX, 0, &face_index) != FcResultMatch) {
FcFontSetDestroy(font_set);
return false;
}
FcFontSetDestroy(font_set);
if (outIdentity) {
outIdentity->fTTCIndex = face_index;
outIdentity->fString.set((const char*)c_filename);
}
if (outFamilyName) {
outFamilyName->set((const char*)post_config_family);
}
if (outStyle) {
*outStyle = GetFontStyle(match);
}
return true;
}
SkStream* SkFontConfigInterfaceDirect::openStream(const FontIdentity& identity) {
return SkStream::NewFromFile(identity.fString.c_str());
}