Fixed file/directory url resolution for external mount point provider.

webkit/chromeos/fileapi/cros_mount_point_provider.cc

   // Copyright (c) 2011 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 "webkit/chromeos/fileapi/cros_mount_point_provider.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_callback_factory.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
 #include "base/stringprintf.h"
+#include "base/synchronization/lock.h"
 #include "base/utf_string_conversions.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCString.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFileSystem.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
 #include "webkit/chromeos/fileapi/file_access_permissions.h"
 #include "webkit/fileapi/file_system_path_manager.h"
 #include "webkit/fileapi/file_system_util.h"
 #include "webkit/glue/webkit_glue.h"
 
 namespace chromeos {
 
 typedef struct {
   const char* local_root_path;
   const char* web_root_path;
 } FixedExposedPaths;
 
+const char kChromeUIScheme[] = "chrome";
+
 // Top level file system elements exposed in FileAPI in ChromeOS:
 FixedExposedPaths fixed_exposed_paths[] = {
     {"/home/chronos/user/", "Downloads"},
     {"/",                   "media"},
-    {"/",                   "tmp"},
 };
 
 CrosMountPointProvider::CrosMountPointProvider(
     scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy)
     : special_storage_policy_(special_storage_policy),
       file_access_permissions_(new FileAccessPermissions()) {
   for (size_t i = 0; i < arraysize(fixed_exposed_paths); i++) {
     mount_point_map_.insert(std::pair<std::string, FilePath>(
         std::string(fixed_exposed_paths[i].web_root_path),
         FilePath(std::string(fixed_exposed_paths[i].local_root_path))));
   }
 }
 
 CrosMountPointProvider::~CrosMountPointProvider() {
 }
 
 // TODO(zelidrag) share with SandboxMountPointProvider impl.
 std::string GetOriginIdentifierFromURL(
     const GURL& url) {
   WebKit::WebSecurityOrigin web_security_origin =
       WebKit::WebSecurityOrigin::createFromString(UTF8ToUTF16(url.spec()));
   return web_security_origin.databaseIdentifier().utf8();
 }
 
-void CrosMountPointProvider::GetFileSystemRootPath(
+bool CrosMountPointProvider::GetRootForVirtualPath(
+    const FilePath& virtual_path, FilePath* root_path) {
+  std::vector<FilePath::StringType> components;
+  virtual_path.GetComponents(&components);
+  if (components.size() < 1) {
+    return false;
+  }
+
+  base::AutoLock locker(lock_);
+  // Check if this root mount point is exposed by this provider.
+  MountPointMap::iterator iter = mount_point_map_.find(components[0]);
+  if (iter == mount_point_map_.end()) {
+    return false;
+  }
+  *root_path = iter->second;
+  return true;
+}
+
+void CrosMountPointProvider::ValidateFileSystemRootAndGetURL(

[kinuko, 2011/04/20 14:44:18]

I'm afraid this new method name may confuse the readers of
SandboxMountPointProvider, where it actually returns a path but not URL.

Actually the url returned by this method is right now not used at the callsite. 
If we do not have a plan to use the returned URL could we simply name this
ValidateFileSystemRoot() and make it only return boolean value?  It shouldn't
contradict to the remaining TODO in the FileSystemOperation (i.e. we shouldn't
call this method when !create cases).
The FileThread version could probably be named
ValidateAndGetFilesystemRootPathOnFileThread then.

Wdyt?  I guess Eric may have some other future plan, but if it makes sense we
can make the followup patch.

     const GURL& origin_url,
     fileapi::FileSystemType type,
     bool create,
     fileapi::FileSystemPathManager::GetRootPathCallback* callback_ptr) {
   DCHECK(type == fileapi::kFileSystemTypeExternal);
-
   std::string name(GetOriginIdentifierFromURL(origin_url));
   name += ':';
   name += fileapi::kExternalName;
-
-  FilePath root_path = FilePath(fileapi::kExternalDir);
-  callback_ptr->Run(!root_path.empty(), root_path, name);
+  FilePath root_path;
+  root_path = FilePath(fileapi::kExternalDir);
+  callback_ptr->Run(true, root_path, name);
 }
 
-// Like GetFileSystemRootPath, but synchronous, and can be called only while
-// running on the file thread.
-FilePath CrosMountPointProvider::GetFileSystemRootPathOnFileThread(
+FilePath CrosMountPointProvider::ValidateFileSystemRootAndGetPathOnFileThread(
     const GURL& origin_url,
     fileapi::FileSystemType type,
     const FilePath& virtual_path,
     bool create) {
   DCHECK(type == fileapi::kFileSystemTypeExternal);
+  FilePath root_path;
+  if (!GetRootForVirtualPath(virtual_path, &root_path))
+    return FilePath();
 
-  std::vector<FilePath::StringType> components;
-  virtual_path.GetComponents(&components);
-  if (components.size() < 1) {
-    return FilePath();
-  }
-
-  // Check if this root directory is exposed by this provider.
-  MountPointMap::iterator iter = mount_point_map_.find(components[0]);
-  if (iter == mount_point_map_.end()) {
-    return FilePath();
-  }
-
-  return iter->second;
+  return root_path;
 }
 
 // TODO(zelidrag): Share this code with SandboxMountPointProvider impl.
 bool CrosMountPointProvider::IsRestrictedFileName(const FilePath& path) const {
   return false;
 }
 
 bool CrosMountPointProvider::IsAccessAllowed(const GURL& origin_url,
                                              fileapi::FileSystemType type,
                                              const FilePath& virtual_path) {
   if (type != fileapi::kFileSystemTypeExternal)
     return false;
+
+  // Permit access to mount points from internal WebUI.
+  if (origin_url.SchemeIs(kChromeUIScheme))
+    return true;
+
   std::string extension_id = origin_url.host();
   // Check first to make sure this extension has fileBrowserHander permissions.
   if (!special_storage_policy_->IsFileHandler(extension_id))
     return false;
+
   return file_access_permissions_->HasAccessPermission(extension_id,
                                                        virtual_path);
 }
 
+void CrosMountPointProvider::AddMountPoint(FilePath mount_point) {
+  base::AutoLock locker(lock_);
+  mount_point_map_.insert(std::pair<std::string, FilePath>(
+      mount_point.BaseName().value(), mount_point.DirName()));
+}
+
+void CrosMountPointProvider::RemoveMountPoint(FilePath mount_point) {
+  base::AutoLock locker(lock_);
+  mount_point_map_.erase(mount_point.BaseName().value());
+}
+
 void CrosMountPointProvider::GrantFullAccessToExtension(
     const std::string& extension_id) {
   DCHECK(special_storage_policy_->IsFileHandler(extension_id));
   if (!special_storage_policy_->IsFileHandler(extension_id))
     return;
   for (MountPointMap::const_iterator iter = mount_point_map_.begin();
        iter != mount_point_map_.end();
        ++iter) {
     GrantFileAccessToExtension(extension_id, FilePath(iter->first));
   }
@@ skipping 18 matching lines @@
   for (MountPointMap::const_iterator iter = mount_point_map_.begin();
        iter != mount_point_map_.end();
        ++iter) {
     root_dirs.push_back(iter->second.Append(iter->first));
   }
   return root_dirs;
 }
 
 }  // namespace chromeos