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 "ProcPidDir.h"
18
19 #include <android-base/file.h>
20 #include <android-base/result.h>
21 #include <errno.h>
22
23 #include "ProcPidStat.h"
24
25 namespace android {
26 namespace automotive {
27 namespace watchdog {
28 namespace testing {
29
30 using android::base::Error;
31 using android::base::Result;
32 using android::base::WriteStringToFile;
33
34 namespace {
35
makeDir(std::string path)36 Result<void> makeDir(std::string path) {
37 if (mkdir(path.c_str(), 0700) && errno != EEXIST) {
38 return Error() << "Could not mkdir " << path << ": " << strerror(errno);
39 }
40 return {};
41 }
42
43 } // namespace
44
populateProcPidDir(const std::string & procDirPath,const std::unordered_map<uint32_t,std::vector<uint32_t>> & pidToTids,const std::unordered_map<uint32_t,std::string> & processStat,const std::unordered_map<uint32_t,std::string> & processStatus,const std::unordered_map<uint32_t,std::string> & threadStat)45 Result<void> populateProcPidDir(
46 const std::string& procDirPath,
47 const std::unordered_map<uint32_t, std::vector<uint32_t>>& pidToTids,
48 const std::unordered_map<uint32_t, std::string>& processStat,
49 const std::unordered_map<uint32_t, std::string>& processStatus,
50 const std::unordered_map<uint32_t, std::string>& threadStat) {
51 for (const auto& it : pidToTids) {
52 // 1. Create /proc/PID dir.
53 const auto& pidDirRes = makeDir(StringPrintf("%s/%" PRIu32, procDirPath.c_str(), it.first));
54 if (!pidDirRes) {
55 return Error() << "Failed to create top-level per-process directory: "
56 << pidDirRes.error();
57 }
58
59 // 2. Create /proc/PID/stat file.
60 uint32_t pid = it.first;
61 if (processStat.find(pid) != processStat.end()) {
62 std::string path = StringPrintf((procDirPath + kStatFileFormat).c_str(), pid);
63 if (!WriteStringToFile(processStat.at(pid), path)) {
64 return Error() << "Failed to write pid stat file " << path;
65 }
66 }
67
68 // 3. Create /proc/PID/status file.
69 if (processStatus.find(pid) != processStatus.end()) {
70 std::string path = StringPrintf((procDirPath + kStatusFileFormat).c_str(), pid);
71 if (!WriteStringToFile(processStatus.at(pid), path)) {
72 return Error() << "Failed to write pid status file " << path;
73 }
74 }
75
76 // 4. Create /proc/PID/task dir.
77 const auto& taskDirRes = makeDir(StringPrintf((procDirPath + kTaskDirFormat).c_str(), pid));
78 if (!taskDirRes) {
79 return Error() << "Failed to create task directory: " << taskDirRes.error();
80 }
81
82 // 5. Create /proc/PID/task/TID dirs and /proc/PID/task/TID/stat files.
83 for (const auto& tid : it.second) {
84 const auto& tidDirRes = makeDir(
85 StringPrintf((procDirPath + kTaskDirFormat + "/%" PRIu32).c_str(), pid, tid));
86 if (!tidDirRes) {
87 return Error() << "Failed to create per-thread directory: " << tidDirRes.error();
88 }
89 if (threadStat.find(tid) != threadStat.end()) {
90 std::string path =
91 StringPrintf((procDirPath + kTaskDirFormat + kStatFileFormat).c_str(), pid,
92 tid);
93 if (!WriteStringToFile(threadStat.at(tid), path)) {
94 return Error() << "Failed to write thread stat file " << path;
95 }
96 }
97 }
98 }
99
100 return {};
101 }
102
103 } // namespace testing
104 } // namespace watchdog
105 } // namespace automotive
106 } // namespace android
107