chrome/common/extensions/extension_resource.h

   1 // Copyright (c) 2012 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 #ifndef CHROME_COMMON_EXTENSIONS_EXTENSION_RESOURCE_H_
   6 #define CHROME_COMMON_EXTENSIONS_EXTENSION_RESOURCE_H_
   7
   8 #include <string>
   9
  10 #include "base/file_path.h"
  11
  12 // Represents a resource inside an extension. For example, an image, or a
  13 // JavaScript file. This is more complicated than just a simple FilePath
  14 // because extension resources can come from multiple physical file locations
  15 // depending on locale.
  16 class ExtensionResource {
  17  public:
  18   // SymlinkPolicy decides whether we'll allow resources to be a symlink to
  19   // anywhere, or whether they must end up within the extension root.
  20   enum SymlinkPolicy {
  21     SYMLINKS_MUST_RESOLVE_WITHIN_ROOT,
  22     FOLLOW_SYMLINKS_ANYWHERE,
  23   };
  24
  25   ExtensionResource();
  26
  27   ExtensionResource(const std::string& extension_id,
  28                     const FilePath& extension_root,
  29                     const FilePath& relative_path);
  30
  31   ~ExtensionResource();
  32
  33   // set_follow_symlinks_anywhere allows the resource to be a symlink to
  34   // anywhere in the filesystem. By default, resources have to be within
  35   // |extension_root| after resolving symlinks.
  36   void set_follow_symlinks_anywhere();
  37
  38   // Returns actual path to the resource (default or locale specific). In the
  39   // browser process, this will DCHECK if not called on the file thread. To
  40   // easily load extension images on the UI thread, see ImageLoadingTracker.
  41   const FilePath& GetFilePath() const;
  42
  43   // Gets the physical file path for the extension resource, taking into account
  44   // localization. In the browser process, this will DCHECK if not called on the
  45   // file thread. To easily load extension images on the UI thread, see
  46   // ImageLoadingTracker.
  47   //
  48   // The relative path must not resolve to a location outside of
  49   // |extension_root|. Iff |file_can_symlink_outside_root| is true, then the
  50   // file can be a symlink that links outside of |extension_root|.
  51   static FilePath GetFilePath(const FilePath& extension_root,
  52                               const FilePath& relative_path,
  53                               SymlinkPolicy symlink_policy);
  54
  55   // Getters
  56   const std::string& extension_id() const { return extension_id_; }
  57   const FilePath& extension_root() const { return extension_root_; }
  58   const FilePath& relative_path() const { return relative_path_; }
  59
  60   bool empty() const { return extension_root().empty(); }
  61
  62   // Unit test helpers.
  63   FilePath::StringType NormalizeSeperators(
  64       const FilePath::StringType& path) const;
  65   bool ComparePathWithDefault(const FilePath& path) const;
  66
  67  private:
  68   // The id of the extension that this resource is associated with.
  69   std::string extension_id_;
  70
  71   // Extension root.
  72   FilePath extension_root_;
  73
  74   // Relative path to resource.
  75   FilePath relative_path_;
  76
  77   // If |follow_symlinks_anywhere_| is true then the resource itself must be
  78   // within |extension_root|, but it can be a symlink to a file that is not.
  79   bool follow_symlinks_anywhere_;
  80
  81   // Full path to extension resource. Starts empty.
  82   mutable FilePath full_resource_path_;
  83 };
  84
  85 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_RESOURCE_H_