1 /*
2  * Copyright 2017, 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 <debuggerd/client.h>
18 
19 #include <fcntl.h>
20 #include <stdio.h>
21 #include <unistd.h>
22 
23 #include <chrono>
24 #include <thread>
25 #include <vector>
26 
27 #include <gtest/gtest.h>
28 
29 #include <android-base/file.h>
30 #include <android-base/properties.h>
31 #include <android-base/stringprintf.h>
32 #include <android-base/strings.h>
33 #include <android-base/unique_fd.h>
34 
35 #include "util.h"
36 
37 using namespace std::chrono_literals;
38 using android::base::unique_fd;
39 
getThreadCount()40 static int getThreadCount() {
41   int threadCount = 1024;
42   std::vector<std::string> characteristics =
43       android::base::Split(android::base::GetProperty("ro.build.characteristics", ""), ",");
44   if (std::find(characteristics.begin(), characteristics.end(), "embedded")
45       != characteristics.end()) {
46     // 128 is the realistic number for iot devices.
47     threadCount = 128;
48   }
49   return threadCount;
50 }
51 
TEST(debuggerd_client,race)52 TEST(debuggerd_client, race) {
53   static int THREAD_COUNT = getThreadCount();
54   pid_t forkpid = fork();
55 
56   ASSERT_NE(-1, forkpid);
57 
58   if (forkpid == 0) {
59     // Spawn a bunch of threads, to make crash_dump take longer.
60     std::vector<std::thread> threads;
61     for (int i = 0; i < THREAD_COUNT; ++i) {
62       threads.emplace_back([]() {
63         while (true) {
64           std::this_thread::sleep_for(60s);
65         }
66       });
67     }
68 
69     std::this_thread::sleep_for(60s);
70     exit(0);
71   }
72 
73   unique_fd pipe_read, pipe_write;
74   ASSERT_TRUE(Pipe(&pipe_read, &pipe_write));
75 
76   // 16 MiB should be enough for everyone.
77   constexpr int PIPE_SIZE = 16 * 1024 * 1024;
78   ASSERT_EQ(PIPE_SIZE, fcntl(pipe_read.get(), F_SETPIPE_SZ, PIPE_SIZE));
79 
80   // Wait for a bit to let the child spawn all of its threads.
81   std::this_thread::sleep_for(1s);
82 
83   ASSERT_TRUE(
84       debuggerd_trigger_dump(forkpid, kDebuggerdNativeBacktrace, 60000, std::move(pipe_write)));
85   // Immediately kill the forked child, to make sure that the dump didn't return early.
86   ASSERT_EQ(0, kill(forkpid, SIGKILL)) << strerror(errno);
87 
88   // Check the output.
89   std::string result;
90   ASSERT_TRUE(android::base::ReadFdToString(pipe_read.get(), &result));
91 
92   // Look for "----- end <PID> -----"
93   int found_end = 0;
94 
95   std::string expected_end = android::base::StringPrintf("----- end %d -----", forkpid);
96 
97   std::vector<std::string> lines = android::base::Split(result, "\n");
98   for (const std::string& line : lines) {
99     if (line == expected_end) {
100       ++found_end;
101     }
102   }
103 
104   EXPECT_EQ(1, found_end) << "\nOutput: \n" << result;
105 }
106 
TEST(debuggerd_client,no_timeout)107 TEST(debuggerd_client, no_timeout) {
108   unique_fd pipe_read, pipe_write;
109   ASSERT_TRUE(Pipe(&pipe_read, &pipe_write));
110 
111   pid_t forkpid = fork();
112   ASSERT_NE(-1, forkpid);
113   if (forkpid == 0) {
114     pipe_write.reset();
115     char dummy;
116     TEMP_FAILURE_RETRY(read(pipe_read.get(), &dummy, sizeof(dummy)));
117     exit(0);
118   }
119 
120   pipe_read.reset();
121 
122   unique_fd output_read, output_write;
123   ASSERT_TRUE(Pipe(&output_read, &output_write));
124   ASSERT_TRUE(
125       debuggerd_trigger_dump(forkpid, kDebuggerdNativeBacktrace, 0, std::move(output_write)));
126 }
127