1 /*
2 * Copyright (C) 2020 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 "Utils.h"
18 #include <hwbinder/HidlSupport.h>
19
20 #include <string.h>
21 #include <android-base/logging.h>
22 #include <android-base/properties.h>
23
24 namespace android::hardware {
25
zeroMemory(uint8_t * data,size_t size)26 void zeroMemory(uint8_t* data, size_t size) {
27 memset(data, 0, size);
28 }
29
file_exists(const std::string & file)30 static bool file_exists(const std::string& file) {
31 int res = access(file.c_str(), F_OK);
32 if (res == 0 || errno == EACCES) return true;
33 return false;
34 }
35
isHwServiceManagerInstalled()36 static bool isHwServiceManagerInstalled() {
37 return file_exists("/system_ext/bin/hwservicemanager") ||
38 file_exists("/system/system_ext/bin/hwservicemanager") ||
39 file_exists("/system/bin/hwservicemanager");
40 }
41
waitForHwServiceManager()42 static bool waitForHwServiceManager() {
43 if (!isHwServiceManagerInstalled()) {
44 return false;
45 }
46 // TODO(b/31559095): need bionic host so that we can use 'prop_info' returned
47 // from WaitForProperty
48 #ifdef __ANDROID__
49 static const char* kHwServicemanagerReadyProperty = "hwservicemanager.ready";
50
51 using std::literals::chrono_literals::operator""s;
52
53 using android::base::WaitForProperty;
54 while (true) {
55 if (base::GetBoolProperty("hwservicemanager.disabled", false)) {
56 return false;
57 }
58 if (WaitForProperty(kHwServicemanagerReadyProperty, "true", 1s)) {
59 return true;
60 }
61 LOG(WARNING) << "Waited for hwservicemanager.ready for a second, waiting another...";
62 }
63 #endif // __ANDROID__
64 return true;
65 }
66
isHwbinderSupportedBlocking()67 bool isHwbinderSupportedBlocking() {
68 return waitForHwServiceManager();
69 }
70 } // namespace android::hardware
71