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 "UidProcStatsCollector.h"
20
21 #include <android-base/file.h>
22 #include <android-base/result.h>
23
24 #include <errno.h>
25
26 namespace android {
27 namespace automotive {
28 namespace watchdog {
29 namespace testing {
30
31 using ::android::base::Error;
32 using ::android::base::Result;
33 using ::android::base::WriteStringToFile;
34
35 namespace {
36
makeDir(std::string path)37 Result<void> makeDir(std::string path) {
38 if (mkdir(path.c_str(), 0700) && errno != EEXIST) {
39 return Error() << "Could not mkdir " << path << ": " << strerror(errno);
40 }
41 return {};
42 }
43
44 } // namespace
45
populateProcPidDir(const std::string & procDirPath,const std::unordered_map<pid_t,std::vector<pid_t>> & pidToTids,const std::unordered_map<pid_t,std::string> & processStat,const std::unordered_map<pid_t,std::string> & processStatus,const std::unordered_map<pid_t,std::string> & threadStat,const std::unordered_map<pid_t,std::string> & threadTimeInState)46 Result<void> populateProcPidDir(const std::string& procDirPath,
47 const std::unordered_map<pid_t, std::vector<pid_t>>& pidToTids,
48 const std::unordered_map<pid_t, std::string>& processStat,
49 const std::unordered_map<pid_t, std::string>& processStatus,
50 const std::unordered_map<pid_t, std::string>& threadStat,
51 const std::unordered_map<pid_t, std::string>& threadTimeInState) {
52 for (const auto& it : pidToTids) {
53 // 1. Create /proc/PID dir.
54 const auto& pidDirRes = makeDir(StringPrintf("%s/%" PRIu32, procDirPath.c_str(), it.first));
55 if (!pidDirRes.ok()) {
56 return Error() << "Failed to create top-level per-process directory: "
57 << pidDirRes.error();
58 }
59
60 // 2. Create /proc/PID/stat file.
61 uint32_t pid = it.first;
62 if (processStat.find(pid) != processStat.end()) {
63 std::string path = StringPrintf((procDirPath + kStatFileFormat).c_str(), pid);
64 if (!WriteStringToFile(processStat.at(pid), path)) {
65 return Error() << "Failed to write pid stat file " << path;
66 }
67 }
68
69 // 3. Create /proc/PID/status file.
70 if (processStatus.find(pid) != processStatus.end()) {
71 std::string path = StringPrintf((procDirPath + kStatusFileFormat).c_str(), pid);
72 if (!WriteStringToFile(processStatus.at(pid), path)) {
73 return Error() << "Failed to write pid status file " << path;
74 }
75 }
76
77 // 4. Create /proc/PID/task dir.
78 const auto& taskDirRes = makeDir(StringPrintf((procDirPath + kTaskDirFormat).c_str(), pid));
79 if (!taskDirRes.ok()) {
80 return Error() << "Failed to create task directory: " << taskDirRes.error();
81 }
82
83 // 5. Create /proc/PID/task/TID dirs, /proc/PID/task/TID/stat and
84 // /proc/PID/task/TID/time_in_state files.
85 for (const auto& tid : it.second) {
86 const auto& tidDirRes = makeDir(
87 StringPrintf((procDirPath + kTaskDirFormat + "/%" PRIu32).c_str(), pid, tid));
88 if (!tidDirRes.ok()) {
89 return Error() << "Failed to create per-thread directory: " << tidDirRes.error();
90 }
91 if (threadStat.find(tid) != threadStat.end()) {
92 std::string path =
93 StringPrintf((procDirPath + kTaskDirFormat + kStatFileFormat).c_str(), pid,
94 tid);
95 if (!WriteStringToFile(threadStat.at(tid), path)) {
96 return Error() << "Failed to write thread stat file " << path;
97 }
98 }
99 if (threadTimeInState.find(tid) != threadTimeInState.end()) {
100 std::string path =
101 StringPrintf((procDirPath + kTaskDirFormat + kTimeInStateFormat).c_str(),
102 pid, tid);
103 if (!WriteStringToFile(threadTimeInState.at(tid), path)) {
104 return Error() << "Failed to write thread time_in_state file " << path;
105 }
106 }
107 }
108 }
109
110 return {};
111 }
112
113 } // namespace testing
114 } // namespace watchdog
115 } // namespace automotive
116 } // namespace android
117