1 /*
2 * Copyright (C) 2015 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 <stdio.h>
18
19 #include <string>
20
21 #include "fs_mgr.h"
22 #include "fs_mgr_priv.h"
23
24 // Returns "_a" or "_b" based on two possible values in kernel cmdline:
25 // - androidboot.slot = a or b OR
26 // - androidboot.slot_suffix = _a or _b
27 // TODO: remove slot_suffix once it's deprecated.
fs_mgr_get_slot_suffix()28 std::string fs_mgr_get_slot_suffix() {
29 std::string slot;
30 std::string ab_suffix;
31
32 if (fs_mgr_get_boot_config("slot", &slot)) {
33 ab_suffix = "_" + slot;
34 } else if (!fs_mgr_get_boot_config("slot_suffix", &ab_suffix)) {
35 ab_suffix = "";
36 }
37 return ab_suffix;
38 }
39
40 // Updates |fstab| for slot_suffix. Returns true on success, false on error.
fs_mgr_update_for_slotselect(struct fstab * fstab)41 bool fs_mgr_update_for_slotselect(struct fstab *fstab) {
42 int n;
43 std::string ab_suffix;
44
45 for (n = 0; n < fstab->num_entries; n++) {
46 if (fstab->recs[n].fs_mgr_flags & MF_SLOTSELECT) {
47 char *tmp;
48 if (ab_suffix.empty()) {
49 ab_suffix = fs_mgr_get_slot_suffix();
50 // Returns false as non A/B devices should not have MF_SLOTSELECT.
51 if (ab_suffix.empty()) return false;
52 }
53 if (asprintf(&tmp, "%s%s", fstab->recs[n].blk_device, ab_suffix.c_str()) > 0) {
54 free(fstab->recs[n].blk_device);
55 fstab->recs[n].blk_device = tmp;
56 } else {
57 return false;
58 }
59 }
60 }
61 return true;
62 }
63