1 /*
2 * Copyright (C) 2014 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 <pty.h>
18
19 #include <gtest/gtest.h>
20
21 #include <pthread.h>
22 #include <sys/ioctl.h>
23
24 #include <atomic>
25
26 #include <android-base/file.h>
27
28 #include "utils.h"
29
TEST(pty,openpty)30 TEST(pty, openpty) {
31 int master, slave;
32 char name[32];
33 struct winsize w = { 123, 456, 9999, 999 };
34 ASSERT_EQ(0, openpty(&master, &slave, name, NULL, &w));
35 ASSERT_NE(-1, master);
36 ASSERT_NE(-1, slave);
37 ASSERT_NE(master, slave);
38
39 char tty_name[32];
40 ASSERT_EQ(0, ttyname_r(slave, tty_name, sizeof(tty_name)));
41 ASSERT_STREQ(tty_name, name);
42
43 struct winsize w_actual;
44 ASSERT_EQ(0, ioctl(slave, TIOCGWINSZ, &w_actual));
45 ASSERT_EQ(w_actual.ws_row, w.ws_row);
46 ASSERT_EQ(w_actual.ws_col, w.ws_col);
47 ASSERT_EQ(w_actual.ws_xpixel, w.ws_xpixel);
48 ASSERT_EQ(w_actual.ws_ypixel, w.ws_ypixel);
49
50 close(master);
51 close(slave);
52 }
53
TEST(pty,forkpty)54 TEST(pty, forkpty) {
55 pid_t sid = getsid(0);
56
57 int master;
58 pid_t pid = forkpty(&master, NULL, NULL, NULL);
59 ASSERT_NE(-1, pid);
60
61 if (pid == 0) {
62 // We're the child.
63 ASSERT_NE(sid, getsid(0));
64 _exit(0);
65 }
66
67 ASSERT_EQ(sid, getsid(0));
68
69 AssertChildExited(pid, 0);
70
71 close(master);
72 }
73
74 struct PtyReader_28979140_Arg {
75 int slave_fd;
76 uint32_t data_count;
77 bool finished;
78 std::atomic<bool> matched;
79 };
80
PtyReader_28979140(PtyReader_28979140_Arg * arg)81 static void PtyReader_28979140(PtyReader_28979140_Arg* arg) {
82 arg->finished = false;
83 cpu_set_t cpus;
84 ASSERT_EQ(0, sched_getaffinity(0, sizeof(cpu_set_t), &cpus));
85 CPU_CLR(0, &cpus);
86 ASSERT_EQ(0, sched_setaffinity(0, sizeof(cpu_set_t), &cpus));
87
88 uint32_t counter = 0;
89 while (counter <= arg->data_count) {
90 char buf[4096]; // Use big buffer to read to hit the bug more easily.
91 size_t to_read = std::min(sizeof(buf), (arg->data_count + 1 - counter) * sizeof(uint32_t));
92 ASSERT_TRUE(android::base::ReadFully(arg->slave_fd, buf, to_read));
93 size_t num_of_value = to_read / sizeof(uint32_t);
94 uint32_t* p = reinterpret_cast<uint32_t*>(buf);
95 while (num_of_value-- > 0) {
96 if (*p++ != counter++) {
97 arg->matched = false;
98 }
99 }
100 }
101 close(arg->slave_fd);
102 arg->finished = true;
103 }
104
TEST(pty,bug_28979140)105 TEST(pty, bug_28979140) {
106 // This test is to test a kernel bug, which uses a lock free ring-buffer to
107 // pass data through a raw pty, but missing necessary memory barriers.
108 if (sysconf(_SC_NPROCESSORS_ONLN) == 1) {
109 GTEST_LOG_(INFO) << "This test tests bug happens only on multiprocessors.";
110 return;
111 }
112 constexpr uint32_t TEST_DATA_COUNT = 200000;
113
114 // 1. Open raw pty.
115 int master;
116 int slave;
117 ASSERT_EQ(0, openpty(&master, &slave, nullptr, nullptr, nullptr));
118 termios tattr;
119 ASSERT_EQ(0, tcgetattr(slave, &tattr));
120 cfmakeraw(&tattr);
121 ASSERT_EQ(0, tcsetattr(slave, TCSADRAIN, &tattr));
122
123 // 2. Create thread for slave reader.
124 pthread_t thread;
125 PtyReader_28979140_Arg arg;
126 arg.slave_fd = slave;
127 arg.data_count = TEST_DATA_COUNT;
128 arg.matched = true;
129 ASSERT_EQ(0, pthread_create(&thread, nullptr,
130 reinterpret_cast<void*(*)(void*)>(PtyReader_28979140),
131 &arg));
132
133 // 3. Make master thread and slave thread running on different cpus:
134 // master thread uses cpu 0, and slave thread uses other cpus.
135 cpu_set_t cpus;
136 CPU_ZERO(&cpus);
137 CPU_SET(0, &cpus);
138 ASSERT_EQ(0, sched_setaffinity(0, sizeof(cpu_set_t), &cpus));
139
140 // 4. Send data to slave.
141 uint32_t counter = 0;
142 while (counter <= TEST_DATA_COUNT) {
143 ASSERT_TRUE(android::base::WriteFully(master, &counter, sizeof(counter)));
144 ASSERT_TRUE(arg.matched) << "failed at count = " << counter;
145 counter++;
146 }
147 ASSERT_EQ(0, pthread_join(thread, nullptr));
148 ASSERT_TRUE(arg.finished);
149 ASSERT_TRUE(arg.matched);
150 close(master);
151 }
152