1 //
2 // Copyright (C) 2016 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 
17 #include "update_engine/utils_android.h"
18 
19 #include <cutils/properties.h>
20 #include <fs_mgr.h>
21 
22 using std::string;
23 
24 namespace chromeos_update_engine {
25 
26 namespace {
27 
28 // Open the appropriate fstab file and fallback to /fstab.device if
29 // that's what's being used.
OpenFSTab()30 static struct fstab* OpenFSTab() {
31   struct fstab* fstab = fs_mgr_read_fstab_default();
32   if (fstab != nullptr)
33     return fstab;
34 
35   fstab = fs_mgr_read_fstab("/fstab.device");
36   return fstab;
37 }
38 
39 }  // namespace
40 
41 namespace utils {
42 
DeviceForMountPoint(const string & mount_point,base::FilePath * device)43 bool DeviceForMountPoint(const string& mount_point, base::FilePath* device) {
44   struct fstab* fstab;
45   struct fstab_rec* record;
46 
47   fstab = OpenFSTab();
48   if (fstab == nullptr) {
49     LOG(ERROR) << "Error opening fstab file.";
50     return false;
51   }
52   record = fs_mgr_get_entry_for_mount_point(fstab, mount_point.c_str());
53   if (record == nullptr) {
54     LOG(ERROR) << "Error finding " << mount_point << " entry in fstab file.";
55     fs_mgr_free_fstab(fstab);
56     return false;
57   }
58 
59   *device = base::FilePath(record->blk_device);
60   fs_mgr_free_fstab(fstab);
61   return true;
62 }
63 
64 }  // namespace utils
65 
66 }  // namespace chromeos_update_engine
67