1 /*
2  * Copyright (C) 2013 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 <gtest/gtest.h>
18 
19 #include <errno.h>
20 #include <signal.h>
21 #include <stdlib.h>
22 #include <sys/select.h>
23 #include <sys/types.h>
24 #include <sys/wait.h>
25 
TEST(sys_select,fd_set_smoke)26 TEST(sys_select, fd_set_smoke) {
27   fd_set fds;
28   FD_ZERO(&fds);
29 
30   for (size_t i = 0; i < 1024; ++i) {
31     EXPECT_FALSE(FD_ISSET(i, &fds));
32   }
33 
34   FD_SET(0, &fds);
35   EXPECT_TRUE(FD_ISSET(0, &fds));
36   EXPECT_FALSE(FD_ISSET(1, &fds));
37   FD_SET(1, &fds);
38   EXPECT_TRUE(FD_ISSET(0, &fds));
39   EXPECT_TRUE(FD_ISSET(1, &fds));
40   FD_CLR(0, &fds);
41   EXPECT_FALSE(FD_ISSET(0, &fds));
42   EXPECT_TRUE(FD_ISSET(1, &fds));
43   FD_CLR(1, &fds);
44   EXPECT_FALSE(FD_ISSET(0, &fds));
45   EXPECT_FALSE(FD_ISSET(1, &fds));
46 }
47 
48 #define DELAY_MSG "1234"
49 
DelayedWrite(int * pid,int * fd)50 static void DelayedWrite(int* pid, int* fd) {
51   int fds[2];
52   ASSERT_EQ(0, pipe(fds));
53 
54   if ((*pid = fork()) == 0) {
55     close(fds[0]);
56     usleep(5000);
57     EXPECT_EQ(5, write(fds[1], DELAY_MSG, sizeof(DELAY_MSG)));
58     close(fds[1]);
59     exit(0);
60   }
61   ASSERT_LT(0, *pid);
62   close(fds[1]);
63 
64   *fd = fds[0];
65 }
66 
DelayedWriteCleanup(int pid,int fd)67 static void DelayedWriteCleanup(int pid, int fd) {
68   char buf[sizeof(DELAY_MSG)];
69   ASSERT_EQ(static_cast<ssize_t>(sizeof(DELAY_MSG)), read(fd, buf, sizeof(DELAY_MSG)));
70   ASSERT_STREQ(DELAY_MSG, buf);
71   ASSERT_EQ(pid, waitpid(pid, NULL, 0));
72 }
73 
TEST(sys_select,select_smoke)74 TEST(sys_select, select_smoke) {
75   fd_set r;
76   FD_ZERO(&r);
77   fd_set w;
78   FD_ZERO(&w);
79   fd_set e;
80   FD_ZERO(&e);
81 
82   FD_SET(STDIN_FILENO, &r);
83   FD_SET(STDOUT_FILENO, &w);
84   FD_SET(STDERR_FILENO, &w);
85 
86   int max = STDERR_FILENO + 1;
87 
88   // Invalid max fd.
89   ASSERT_EQ(-1, select(-1, &r, &w, &e, NULL));
90   ASSERT_EQ(EINVAL, errno);
91 
92   ASSERT_EQ(2, select(max, &r, &w, &e, NULL));
93 
94   // Invalid timeout.
95   timeval tv;
96   tv.tv_sec = -1;
97   tv.tv_usec = 0;
98   ASSERT_EQ(-1, select(max, &r, &w, &e, &tv));
99   ASSERT_EQ(EINVAL, errno);
100 
101   // Valid timeout...
102   tv.tv_sec = 1;
103   int pid, fd;
104   DelayedWrite(&pid, &fd);
105 
106   FD_ZERO(&r);
107   FD_SET(fd, &r);
108   ASSERT_EQ(1, select(fd+1, &r, NULL, NULL, &tv));
109   // Both tv_sec and tv_nsec should have been updated.
110   ASSERT_EQ(0, tv.tv_sec);
111   ASSERT_NE(0, tv.tv_usec);
112 
113   DelayedWriteCleanup(pid, fd);
114 }
115 
TEST(sys_select,pselect_smoke)116 TEST(sys_select, pselect_smoke) {
117   sigset_t ss;
118   sigemptyset(&ss);
119   sigaddset(&ss, SIGPIPE);
120 
121   fd_set r;
122   FD_ZERO(&r);
123   fd_set w;
124   FD_ZERO(&w);
125   fd_set e;
126   FD_ZERO(&e);
127 
128   FD_SET(STDIN_FILENO, &r);
129   FD_SET(STDOUT_FILENO, &w);
130   FD_SET(STDERR_FILENO, &w);
131 
132   int max = STDERR_FILENO + 1;
133 
134   // Invalid max fd.
135   ASSERT_EQ(-1, pselect(-1, &r, &w, &e, NULL, &ss));
136   ASSERT_EQ(EINVAL, errno);
137 
138   ASSERT_EQ(2, pselect(max, &r, &w, &e, NULL, &ss));
139 
140   // Invalid timeout.
141   timespec tv;
142   tv.tv_sec = -1;
143   tv.tv_nsec = 0;
144   ASSERT_EQ(-1, pselect(max, &r, &w, &e, &tv, &ss));
145   ASSERT_EQ(EINVAL, errno);
146 
147   // Valid timeout...
148   tv.tv_sec = 1;
149   int pid, fd;
150   DelayedWrite(&pid, &fd);
151 
152   FD_ZERO(&r);
153   FD_SET(fd, &r);
154   ASSERT_EQ(1, pselect(fd+1, &r, NULL, NULL, &tv, NULL));
155   // Neither tv_sec nor tv_nsec should have been updated.
156   ASSERT_EQ(1, tv.tv_sec);
157   ASSERT_EQ(0, tv.tv_nsec);
158 
159   DelayedWriteCleanup(pid, fd);
160 }
161