gdata: Change permissions of cache persistent directory.

chrome/browser/chromeos/gdata/gdata_file_system.cc

 // Copyright (c) 2012 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 "chrome/browser/chromeos/gdata/gdata_file_system.h"
 
 #include <errno.h>
+#include <sys/stat.h>
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/chromeos/chromeos_version.h"
 #include "base/eintr_wrapper.h"
 #include "base/file_util.h"
 #include "base/json/json_file_value_serializer.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
@@ skipping 182 matching lines @@
                  << ": \"" << strerror(errno)
                  << "\", " << error;
     } else {
       DVLOG(1) << "Created dir " << paths_to_create[i].value();
     }
   }
 
   return error;
 }
 
+// Changes the permissions of |file_path| to |permissions|.
+// Returns the platform error code of the operation.
+base::PlatformFileError ChangeFilePermissions(const FilePath& file_path,
+                                              mode_t permissions) {
+  base::PlatformFileError error = base::PLATFORM_FILE_OK;
+
+  if (chmod(file_path.value().c_str(), permissions) != 0) {
+    error = SystemToPlatformError(errno);
+    PLOG(ERROR) << "Error changing permissions of " << file_path.value();

[kuan, 2012/04/13 02:12:13]

if u want more informative log, u can append strerror(errno).

[Ben Chan, 2012/04/13 03:05:21]

PLOG() actually does that but is preferred because it calls
safe_strerror(errno), which is multi-thread safe:

http://code.google.com/codesearch#OAMlx_jo-ck/src/base/logging.cc&type=cs&l=797

I notice that other code in gdata uses strerror(errno). we should consider
converting those to PLOG().

[kuan, 2012/04/13 03:30:59]

i didn't know that, gd to know, thanks :)

+  } else {
+    DVLOG(1) << "Changed permissions of " << file_path.value();
+  }
+
+  return error;
+}
+
 // Modifies cache state of file on IO thread pool, which involves:
 // - moving or copying file (per |file_operation_type|) from |source_path| to
 //  |dest_path| if they're different
 // - deleting symlink if |symlink_path| is not empty
 // - creating symlink if |symlink_path| is not empty and |create_symlink| is
 //   true.
 base::PlatformFileError ModifyCacheState(
     const FilePath& source_path,
     const FilePath& dest_path,
     GDataFileSystem::FileOperationType file_operation_type,
@@ skipping 3025 matching lines @@
 void GDataFileSystem::InitializeCacheIfNecessary() {
   // Lock to access cache_initialization_started_;
   base::AutoLock lock(lock_);
   UnsafeInitializeCacheIfNecessary();
 }
 
 //========= GDataFileSystem: Cache tasks that ran on io thread pool ============
 
 void GDataFileSystem::InitializeCacheOnIOThreadPool() {
   base::PlatformFileError error = CreateCacheDirectories(cache_paths_);
-
   if (error != base::PLATFORM_FILE_OK)
     return;
 
+  // Change permissions of cache persistent directory to u+rwx,og+x in order to
+  // allow archive files in that directory to be mounted by cros-disks.
+  error = ChangeFilePermissions(
+      gdata_cache_path_.Append(kGDataCachePersistentDir),

[kuan, 2012/04/13 02:12:13]

u can use cache_paths_[GDataRootDirectory::CACHE_TYPE_PERSISTENT].

[Ben Chan, 2012/04/13 03:05:21]

Done.

+      S_IRWXU | S_IXGRP | S_IXOTH);
+  if (error != base::PLATFORM_FILE_OK)
+    return;
+
   // Scan cache persistent and tmp directories to enumerate all files and create
   // corresponding entries for cache map.
   GDataRootDirectory::CacheMap cache_map;
   ScanCacheDirectory(GDataRootDirectory::CACHE_TYPE_PERSISTENT, &cache_map);
   ScanCacheDirectory(GDataRootDirectory::CACHE_TYPE_TMP, &cache_map);
 
   // Then scan pinned and outgoing directories to update existing entries in
   // cache map, or create new ones for pinned symlinks to /dev/null which target
   // nothing.
   // Pinned and outgoing directories should be scanned after the persistent
@@ skipping 874 matching lines @@
   pref_registrar_->Init(profile_->GetPrefs());
   pref_registrar_->Add(prefs::kDisableGDataHostedFiles, this);
 }
 
 void SetFreeDiskSpaceGetterForTesting(FreeDiskSpaceGetterInterface* getter) {
   delete global_free_disk_getter_for_testing;  // Safe to delete NULL;
   global_free_disk_getter_for_testing = getter;
 }
 
 }  // namespace gdata