Move PPB_TrueTypeFont_Dev host from renderer to browser.

content/browser/renderer_host/font_utils_linux.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <fcntl.h>
+#include <fontconfig/fontconfig.h>
+#include <sys/poll.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+
+#include "content/common/sandbox_linux/sandbox_linux.h"
+#include "content/common/set_process_title.h"
+#include "ppapi/c/trusted/ppb_browser_font_trusted.h"
+#include "third_party/npapi/bindings/npapi_extensions.h"
+
+namespace {
+
+// MSCharSetToFontconfig translates a Microsoft charset identifier to a
+// fontconfig language set by appending to |langset|.
+// Returns true if |langset| is Latin/Greek/Cyrillic.
+bool MSCharSetToFontconfig(FcLangSet* langset, unsigned fdwCharSet) {
+  // We have need to translate raw fdwCharSet values into terms that
+  // fontconfig can understand. (See the description of fdwCharSet in the MSDN
+  // documentation for CreateFont:
+  // http://msdn.microsoft.com/en-us/library/dd183499(VS.85).aspx )
+  //
+  // Although the argument is /called/ 'charset', the actual values conflate
+  // character sets (which are sets of Unicode code points) and character
+  // encodings (which are algorithms for turning a series of bits into a
+  // series of code points.) Sometimes the values will name a language,
+  // sometimes they'll name an encoding. In the latter case I'm assuming that
+  // they mean the set of code points in the domain of that encoding.
+  //
+  // fontconfig deals with ISO 639-1 language codes:
+  //   http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes
+  //
+  // So, for each of the documented fdwCharSet values I've had to take a
+  // guess at the set of ISO 639-1 languages intended.
+
+  bool is_lgc = false;
+  switch (fdwCharSet) {
+    case NPCharsetAnsi:
+    // These values I don't really know what to do with, so I'm going to map
+    // them to English also.
+    case NPCharsetDefault:
+    case NPCharsetMac:
+    case NPCharsetOEM:
+    case NPCharsetSymbol:
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("en"));
+      break;
+    case NPCharsetBaltic:
+      // The three baltic languages.
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("et"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("lv"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("lt"));
+      break;
+    case NPCharsetChineseBIG5:
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("zh-tw"));
+      break;
+    case NPCharsetGB2312:
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("zh-cn"));
+      break;
+    case NPCharsetEastEurope:
+      // A scattering of eastern European languages.
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("pl"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("cs"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("sk"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("hu"));
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("hr"));
+      break;
+    case NPCharsetGreek:
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("el"));
+      break;
+    case NPCharsetHangul:
+    case NPCharsetJohab:
+      // Korean
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("ko"));
+      break;
+    case NPCharsetRussian:
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("ru"));
+      break;
+    case NPCharsetShiftJIS:
+      // Japanese
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("ja"));
+      break;
+    case NPCharsetTurkish:
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("tr"));
+      break;
+    case NPCharsetVietnamese:
+      is_lgc = true;
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("vi"));
+      break;
+    case NPCharsetArabic:
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("ar"));
+      break;
+    case NPCharsetHebrew:
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("he"));
+      break;
+    case NPCharsetThai:
+      FcLangSetAdd(langset, reinterpret_cast<const FcChar8*>("th"));
+      break;
+      // default:
+      // Don't add any languages in that case that we don't recognise the
+      // constant.
+  }
+  return is_lgc;
+}
+
+}  // namespace
+
+namespace content {
+
+int MatchFontFaceWithFallback(const std::string& face,
+                              bool is_bold,
+                              bool is_italic,
+                              uint32 charset,
+                              uint32 fallback_family) {
+  FcLangSet* langset = FcLangSetCreate();
+  bool is_lgc = MSCharSetToFontconfig(langset, charset);
+  FcPattern* pattern = FcPatternCreate();
+  FcPatternAddString(
+      pattern, FC_FAMILY, reinterpret_cast<const FcChar8*>(face.c_str()));
+
+  // TODO(thestig) Check if we can access Chrome's per-script font preference
+  // here and select better default fonts for non-LGC case.
+  std::string generic_font_name;
+  if (is_lgc) {
+    switch (fallback_family) {
+      case PP_BROWSERFONT_TRUSTED_FAMILY_SERIF:
+        generic_font_name = "Times New Roman";
+        break;
+      case PP_BROWSERFONT_TRUSTED_FAMILY_SANSSERIF:
+        generic_font_name = "Arial";
+        break;
+      case PP_BROWSERFONT_TRUSTED_FAMILY_MONOSPACE:
+        generic_font_name = "Courier New";
+        break;
+    }
+  }
+  if (!generic_font_name.empty()) {
+    const FcChar8* fc_generic_font_name =
+        reinterpret_cast<const FcChar8*>(generic_font_name.c_str());
+    FcPatternAddString(pattern, FC_FAMILY, fc_generic_font_name);
+  }
+
+  if (is_bold)
+    FcPatternAddInteger(pattern, FC_WEIGHT, FC_WEIGHT_BOLD);
+  if (is_italic)
+    FcPatternAddInteger(pattern, FC_SLANT, FC_SLANT_ITALIC);
+  FcPatternAddLangSet(pattern, FC_LANG, langset);
+  FcPatternAddBool(pattern, FC_SCALABLE, FcTrue);
+  FcConfigSubstitute(NULL, pattern, FcMatchPattern);
+  FcDefaultSubstitute(pattern);
+
+  FcResult result;
+  FcFontSet* font_set = FcFontSort(0, pattern, 0, 0, &result);
+  int font_fd = -1;
+  int good_enough_index = -1;
+  bool good_enough_index_set = false;
+
+  if (font_set) {
+    for (int i = 0; i < font_set->nfont; ++i) {
+      FcPattern* current = font_set->fonts[i];
+
+      // Older versions of fontconfig have a bug where they cannot select
+      // only scalable fonts so we have to manually filter the results.
+      FcBool is_scalable;
+      if (FcPatternGetBool(current, FC_SCALABLE, 0, &is_scalable) !=
+              FcResultMatch ||
+          !is_scalable) {
+        continue;
+      }
+
+      FcChar8* c_filename;
+      if (FcPatternGetString(current, FC_FILE, 0, &c_filename) !=
+          FcResultMatch) {
+        continue;
+      }
+
+      // We only want to return sfnt (TrueType) based fonts. We don't have a
+      // very good way of detecting this so we'll filter based on the
+      // filename.
+      bool is_sfnt = false;
+      static const char kSFNTExtensions[][5] = {".ttf", ".otc", ".TTF", ".ttc",
+                                                ""};
+      const size_t filename_len = strlen(reinterpret_cast<char*>(c_filename));
+      for (unsigned j = 0;; j++) {
+        if (kSFNTExtensions[j][0] == 0) {
+          // None of the extensions matched.
+          break;
+        }
+        const size_t ext_len = strlen(kSFNTExtensions[j]);
+        if (filename_len > ext_len &&
+            memcmp(c_filename + filename_len - ext_len,
+                   kSFNTExtensions[j],
+                   ext_len) == 0) {
+          is_sfnt = true;
+          break;
+        }
+      }
+
+      if (!is_sfnt)
+        continue;
+
+      // This font is good enough to pass muster, but we might be able to do
+      // better with subsequent ones.
+      if (!good_enough_index_set) {
+        good_enough_index = i;
+        good_enough_index_set = true;
+      }
+
+      FcValue matrix;
+      bool have_matrix = FcPatternGet(current, FC_MATRIX, 0, &matrix) == 0;
+
+      if (is_italic && have_matrix) {
+        // we asked for an italic font, but fontconfig is giving us a
+        // non-italic font with a transformation matrix.
+        continue;
+      }
+
+      FcValue embolden;
+      const bool have_embolden =
+          FcPatternGet(current, FC_EMBOLDEN, 0, &embolden) == 0;
+
+      if (is_bold && have_embolden) {
+        // we asked for a bold font, but fontconfig gave us a non-bold font
+        // and asked us to apply fake bolding.
+        continue;
+      }
+
+      font_fd = open(reinterpret_cast<char*>(c_filename), O_RDONLY);

[piman, 2014/06/19 20:03:42]

Do we need to HANDLE_EINTR?

[bbudge, 2014/06/21 14:12:49]

Probably. Done.

+      if (font_fd >= 0)
+        break;
+    }
+  }
+
+  if (font_fd == -1 && good_enough_index_set) {
+    // We didn't find a font that we liked, so we fallback to something
+    // acceptable.
+    FcPattern* current = font_set->fonts[good_enough_index];
+    FcChar8* c_filename;
+    FcPatternGetString(current, FC_FILE, 0, &c_filename);
+    font_fd = open(reinterpret_cast<char*>(c_filename), O_RDONLY);

[piman, 2014/06/19 20:03:42]

Do we need to HANDLE_EINTR?

[bbudge, 2014/06/21 14:12:49]

Probably. Done.

+  }
+
+  if (font_set)
+    FcFontSetDestroy(font_set);
+  FcPatternDestroy(pattern);
+
+  return font_fd;
+}
+
+}  // namespace content