re-land 187283 -- switch to skia's version of SkFontHost_fontconfig

skia/ext/SkFontHost_fontconfig_direct.cpp

Index: skia/ext/SkFontHost_fontconfig_direct.cpp
===================================================================
--- skia/ext/SkFontHost_fontconfig_direct.cpp	(revision 187566)
+++ skia/ext/SkFontHost_fontconfig_direct.cpp	(working copy)
@@ -1,504 +0,0 @@
-/* libs/graphics/ports/SkFontHost_fontconfig_direct.cpp
-**
-** Copyright 2009, Google Inc.
-**
-** Licensed under the Apache License, Version 2.0 (the "License");
-** you may not use this file except in compliance with the License.
-** You may obtain a copy of the License at
-**
-**     http://www.apache.org/licenses/LICENSE-2.0
-**
-** Unless required by applicable law or agreed to in writing, software
-** distributed under the License is distributed on an "AS IS" BASIS,
-** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-** See the License for the specific language governing permissions and
-** limitations under the License.
-*/
-
-#include "skia/ext/SkFontHost_fontconfig_direct.h"
-
-#include <unistd.h>
-#include <fcntl.h>
-
-#include <fontconfig/fontconfig.h>
-
-#include "third_party/skia/include/core/SkTypeface.h"
-#include "third_party/skia/include/core/SkUtils.h"
-
-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,
-};
-
-// 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"},
-    };
-
-    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;
-}
-
-inline unsigned FileFaceIdToFileId(unsigned filefaceid)
-{
-  return filefaceid >> 4;
-}
-
-inline unsigned FileIdAndFaceIndexToFileFaceId(unsigned fileid, int face_index)
-{
-  SkASSERT((face_index & 0xfu) == face_index);
-  return (fileid << 4) | face_index;
-}
-
-// 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|.
-bool GetFontProperties(FcPattern* font,
-                       std::string* font_family,
-                       bool* is_bold,
-                       bool* is_italic) {
-  FcChar8* c_family;
-  if (FcPatternGetString(font, FC_FAMILY, 0, &c_family))
-    return false;
- 
-  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;
-
-  *is_bold = resulting_bold > FC_WEIGHT_MEDIUM && !have_embolden;
-  *is_italic = resulting_italic > FC_SLANT_ROMAN && !have_matrix;
-  *font_family = reinterpret_cast<char*>(c_family);
-
-  return true;
-}
-
-}  // anonymous namespace
-
-FontConfigDirect::FontConfigDirect()
-    : next_file_id_(0) {
-  FcInit();
-}
-
-FontConfigDirect::~FontConfigDirect() {
-}
-
-bool FontConfigDirect::Match(std::string* result_family,
-                             unsigned* result_filefaceid,
-                             bool filefaceid_valid, unsigned filefaceid,
-                             const std::string& family,
-                             const void* data, size_t characters_bytes,
-                             bool* is_bold, bool* is_italic) {
-    if (family.length() > kMaxFontFamilyLength)
-        return false;
-
-    SkAutoMutexAcquire ac(mutex_);
-
-    // Given |family|, |is_bold| and |is_italic| but not |data|, the result will
-    // be a function of these three parameters, and thus eligible for caching.
-    // This is the fast path for |SkTypeface::CreateFromName()|.
-    bool eligible_for_cache = !family.empty() && is_bold && is_italic && !data;
-    if (eligible_for_cache) {
-        int style = (*is_bold ? SkTypeface::kBold : 0 ) |
-                    (*is_italic ? SkTypeface::kItalic : 0);
-        FontMatchKey key = FontMatchKey(family, style);
-        const std::map<FontMatchKey, FontMatch>::const_iterator i =
-            font_match_cache_.find(key);
-        if (i != font_match_cache_.end()) {
-            *is_bold = i->second.is_bold;
-            *is_italic = i->second.is_italic;
-            if (result_family)
-                *result_family = i->second.family;
-            if (result_filefaceid)
-                *result_filefaceid = i->second.filefaceid;
-            return true;
-        }
-    }
-
-    FcPattern* pattern = FcPatternCreate();
-
-    if (filefaceid_valid) {
-        const std::map<unsigned, std::string>::const_iterator
-            i = fileid_to_filename_.find(FileFaceIdToFileId(filefaceid));
-        if (i == fileid_to_filename_.end()) {
-            FcPatternDestroy(pattern);
-            return false;
-        }
-        int face_index = filefaceid & 0xfu;
-        FcPatternAddString(pattern, FC_FILE,
-            reinterpret_cast<const FcChar8*>(i->second.c_str()));
-        // face_index is added only when family is empty because it is not
-        // necessary to uniquiely identify a font if both file and
-        // family are given.
-        if (family.empty())
-            FcPatternAddInteger(pattern, FC_INDEX, face_index);
-    }
-    if (!family.empty()) {
-        FcPatternAddString(pattern, FC_FAMILY, (FcChar8*) family.c_str());
-    }
-
-    FcCharSet* charset = NULL;
-    if (data) {
-        charset = FcCharSetCreate();
-        const uint16_t* chars = (const uint16_t*)data;
-        const uint16_t* stop = chars + characters_bytes/2;
-        while (chars < stop) {
-            FcCharSetAddChar(charset, SkUTF16_NextUnichar(&chars));
-        }
-        FcPatternAddCharSet(pattern, FC_CHARSET, charset);
-        FcCharSetDestroy(charset);  // pattern now owns it.
-    }
-
-    FcPatternAddInteger(pattern, FC_WEIGHT,
-                        is_bold && *is_bold ? FC_WEIGHT_BOLD
-                                            : FC_WEIGHT_NORMAL);
-    FcPatternAddInteger(pattern, FC_SLANT,
-                        is_italic && *is_italic ? 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, family);
-    if (!match) {
-        FcPatternDestroy(pattern);
-        FcFontSetDestroy(font_set);
-        return false;
-    }
-
-    FcPatternDestroy(pattern);
-
-    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;
-    }
-
-    FontMatch font_match;
-    if (filefaceid_valid) {
-        font_match.filefaceid = filefaceid;
-    } else {
-        unsigned out_fileid;
-        const std::string filename(reinterpret_cast<char*>(c_filename));
-        const std::map<std::string, unsigned>::const_iterator
-            i = filename_to_fileid_.find(filename);
-        if (i == filename_to_fileid_.end()) {
-            out_fileid = next_file_id_++;
-            filename_to_fileid_[filename] = out_fileid;
-            fileid_to_filename_[out_fileid] = filename;
-        } else {
-            out_fileid = i->second;
-        }
-        // fileid stored in filename_to_fileid_ and fileid_to_filename_ is
-        // unique only up to the font file. We have to encode face_index for
-        // the out param.
-        font_match.filefaceid =
-            FileIdAndFaceIndexToFileFaceId(out_fileid, face_index);
-    }
-
-    bool success = GetFontProperties(match,
-                                     &font_match.family,
-                                     &font_match.is_bold,
-                                     &font_match.is_italic);
-    FcFontSetDestroy(font_set);
-
-    if (success) {
-        // If eligible, cache the result of the matching.
-        if (eligible_for_cache) {
-            int style = (*is_bold ? SkTypeface::kBold : 0 ) |
-                        (*is_italic ? SkTypeface::kItalic : 0);
-            font_match_cache_[FontMatchKey(family, style)] = font_match;
-        }
-
-        if (result_family)
-            *result_family = font_match.family;
-        if (result_filefaceid)
-            *result_filefaceid = font_match.filefaceid;
-        if (is_bold)
-            *is_bold = font_match.is_bold;
-        if (is_italic)
-            *is_italic = font_match.is_italic;
-    }
-
-    return success;
-}
-
-int FontConfigDirect::Open(unsigned filefaceid) {
-    SkAutoMutexAcquire ac(mutex_);
-    const std::map<unsigned, std::string>::const_iterator
-        i = fileid_to_filename_.find(FileFaceIdToFileId(filefaceid));
-    if (i == fileid_to_filename_.end())
-        return -1;
-
-    return open(i->second.c_str(), O_RDONLY);
-}