chrome/common/favicon/favicon_url_parser.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/common/favicon/favicon_url_parser.h"
   6
   7 #include "base/strings/string_number_conversions.h"
   8 #include "chrome/common/favicon/favicon_types.h"
   9 #include "net/url_request/url_request.h"
  10 #include "ui/base/layout.h"
  11 #include "ui/base/webui/web_ui_util.h"
  12 #include "ui/gfx/favicon_size.h"
  13
  14 namespace {
  15
  16 // Parameters which can be used in chrome://favicon path. See file
  17 // "chrome/browser/ui/webui/favicon_source.h" for a description of
  18 // what each does.
  19 const char kIconURLParameter[] = "iconurl/";
  20 const char kLargestParameter[] = "largest/";
  21 const char kOriginParameter[] = "origin/";
  22 const char kSizeParameter[] = "size/";
  23
  24 // Returns true if |search| is a substring of |path| which starts at
  25 // |start_index|.
  26 bool HasSubstringAt(const std::string& path,
  27                     size_t start_index,
  28                     const std::string& search) {
  29   return path.compare(start_index, search.length(), search) == 0;
  30 }
  31
  32 }  // namespace
  33
  34 namespace chrome {
  35
  36 bool ParseFaviconPath(const std::string& path,
  37                       int icon_types,
  38                       ParsedFaviconPath* parsed) {
  39   parsed->is_icon_url = false;
  40   parsed->url = "";
  41   parsed->size_in_dip = gfx::kFaviconSize;
  42   parsed->scale_factor = ui::SCALE_FACTOR_100P;
  43   parsed->path_index = -1;
  44
  45   if (path.empty())
  46     return false;
  47
  48   size_t parsed_index = 0;
  49   if (HasSubstringAt(path, parsed_index, kLargestParameter)) {
  50     parsed_index += strlen(kLargestParameter);
  51     parsed->size_in_dip = 0;
  52   } else if (HasSubstringAt(path, parsed_index, kSizeParameter)) {
  53     parsed_index += strlen(kSizeParameter);
  54
  55     size_t slash = path.find("/", parsed_index);
  56     if (slash == std::string::npos)
  57       return false;
  58
  59     size_t scale_delimiter = path.find("@", parsed_index);
  60     std::string size_str;
  61     std::string scale_str;
  62     if (scale_delimiter == std::string::npos) {
  63       // Support the legacy size format of 'size/aa/' where 'aa' is the desired
  64       // size in DIP for the sake of not regressing the extensions which use it.
  65       size_str = path.substr(parsed_index, slash - parsed_index);
  66     } else {
  67       size_str = path.substr(parsed_index, scale_delimiter - parsed_index);
  68       scale_str = path.substr(scale_delimiter + 1,
  69                               slash - scale_delimiter - 1);
  70     }
  71
  72     if (!base::StringToInt(size_str, &parsed->size_in_dip))
  73       return false;
  74
  75     if (parsed->size_in_dip != (gfx::kFaviconSize * 4) &&
  76         parsed->size_in_dip != (gfx::kFaviconSize * 2)) {
  77       // Only 64x64, 32x32 and 16x16 icons are supported.
  78       parsed->size_in_dip = gfx::kFaviconSize;
  79     }
  80
  81     if (!scale_str.empty())
  82       webui::ParseScaleFactor(scale_str, &parsed->scale_factor);
  83
  84     // Return the default favicon (as opposed to a resized favicon) for
  85     // favicon sizes which are not cached by the favicon service.
  86     // Currently the favicon service caches:
  87     // - favicons of sizes "gfx::kFaviconSize * scale factor" px of type FAVICON
  88     //   where scale factor is one of FaviconUtil::GetFaviconScaleFactors().
  89     // - the largest TOUCH_ICON / TOUCH_PRECOMPOSED_ICON
  90     if (parsed->size_in_dip != gfx::kFaviconSize &&
  91         icon_types == chrome::FAVICON)
  92       return false;
  93
  94     parsed_index = slash + 1;
  95   }
  96
  97   if (HasSubstringAt(path, parsed_index, kIconURLParameter)) {
  98     parsed_index += strlen(kIconURLParameter);
  99     parsed->is_icon_url = true;
 100     parsed->url = path.substr(parsed_index);
 101   } else {
 102     // URL requests prefixed with "origin/" are converted to a form with an
 103     // empty path and a valid scheme. (e.g., example.com -->
 104     // http://example.com/ or http://example.com/a --> http://example.com/)
 105     if (HasSubstringAt(path, parsed_index, kOriginParameter)) {
 106       parsed_index += strlen(kOriginParameter);
 107       std::string possibly_invalid_url = path.substr(parsed_index);
 108
 109       // If the URL does not specify a scheme (e.g., example.com instead of
 110       // http://example.com), add "http://" as a default.
 111       if (!GURL(possibly_invalid_url).has_scheme())
 112         possibly_invalid_url = "http://" + possibly_invalid_url;
 113
 114       // Strip the path beyond the top-level domain.
 115       parsed->url = GURL(possibly_invalid_url).GetOrigin().spec();
 116     } else {
 117       parsed->url = path.substr(parsed_index);
 118     }
 119   }
 120
 121   // The parsed index needs to be returned in order to allow Instant Extended
 122   // to translate favicon URLs using advanced parameters.
 123   // Example:
 124   //   "chrome-search://favicon/size/16@2x/<renderer-id>/<most-visited-id>"
 125   // would be translated to:
 126   //   "chrome-search://favicon/size/16@2x/<most-visited-item-with-given-id>".
 127   parsed->path_index = parsed_index;
 128   return true;
 129 }
 130
 131 }  // namespace chrome