1 | /* Tests for POSIX timer implementation using another process's CPU clock. */ |
2 | |
3 | #include <unistd.h> |
4 | |
5 | #if _POSIX_THREADS && defined _POSIX_CPUTIME |
6 | |
7 | #include <errno.h> |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <string.h> |
11 | #include <fcntl.h> |
12 | #include <time.h> |
13 | #include <signal.h> |
14 | #include <sys/wait.h> |
15 | |
16 | static clockid_t child_clock; |
17 | |
18 | #define TEST_CLOCK child_clock |
19 | #define TEST_CLOCK_MISSING(clock) \ |
20 | (setup_test () ? "other-process CPU clock timer support" : NULL) |
21 | |
22 | /* This function is intended to rack up both user and system time. */ |
23 | static void |
24 | chew_cpu (void) |
25 | { |
26 | while (1) |
27 | { |
28 | static volatile char buf[4096]; |
29 | for (int i = 0; i < 100; ++i) |
30 | for (size_t j = 0; j < sizeof buf; ++j) |
31 | buf[j] = 0xaa; |
32 | int nullfd = open (file: "/dev/null" , O_WRONLY); |
33 | for (int i = 0; i < 100; ++i) |
34 | for (size_t j = 0; j < sizeof buf; ++j) |
35 | buf[j] = 0xbb; |
36 | write (nullfd, (char *) buf, sizeof buf); |
37 | close (fd: nullfd); |
38 | if (getppid () == 1) |
39 | _exit (2); |
40 | } |
41 | } |
42 | |
43 | static pid_t child; |
44 | static void |
45 | cleanup_child (void) |
46 | { |
47 | if (child <= 0) |
48 | return; |
49 | if (kill (pid: child, SIGKILL) < 0 && errno != ESRCH) |
50 | printf (format: "cannot kill child %d: %m\n" , child); |
51 | else |
52 | { |
53 | int status; |
54 | errno = 0; |
55 | if (waitpid (pid: child, stat_loc: &status, options: 0) != child) |
56 | printf (format: "waitpid %d: %m\n" , child); |
57 | } |
58 | } |
59 | #define CLEANUP_HANDLER cleanup_child () |
60 | |
61 | static int |
62 | setup_test (void) |
63 | { |
64 | /* Test timers on a process CPU clock by having a child process eating |
65 | CPU. First make sure we can make such timers at all. */ |
66 | |
67 | int pipefd[2]; |
68 | if (pipe (pipedes: pipefd) < 0) |
69 | { |
70 | printf (format: "pipe: %m\n" ); |
71 | exit (1); |
72 | } |
73 | |
74 | child = fork (); |
75 | |
76 | if (child == 0) |
77 | { |
78 | char c; |
79 | close (fd: pipefd[1]); |
80 | if (read (pipefd[0], &c, 1) == 1) |
81 | chew_cpu (); |
82 | _exit (1); |
83 | } |
84 | |
85 | if (child < 0) |
86 | { |
87 | printf (format: "fork: %m\n" ); |
88 | exit (1); |
89 | } |
90 | |
91 | atexit (func: &cleanup_child); |
92 | |
93 | close (fd: pipefd[0]); |
94 | |
95 | int e = clock_getcpuclockid (pid: child, clock_id: &child_clock); |
96 | if (e == EPERM) |
97 | { |
98 | puts (s: "clock_getcpuclockid does not support other processes" ); |
99 | return 1; |
100 | } |
101 | if (e != 0) |
102 | { |
103 | printf (format: "clock_getcpuclockid: %s\n" , strerror (errnum: e)); |
104 | exit (1); |
105 | } |
106 | |
107 | timer_t t; |
108 | if (timer_create (TEST_CLOCK, NULL, timerid: &t) != 0) |
109 | { |
110 | printf (format: "timer_create: %m\n" ); |
111 | return 1; |
112 | } |
113 | timer_delete (timerid: t); |
114 | |
115 | /* Get the child started chewing. */ |
116 | if (write (pipefd[1], "x" , 1) != 1) |
117 | { |
118 | printf (format: "write to pipe: %m\n" ); |
119 | return 1; |
120 | } |
121 | close (fd: pipefd[1]); |
122 | |
123 | return 0; |
124 | } |
125 | |
126 | #else |
127 | # define TEST_CLOCK_MISSING(clock) "process clocks" |
128 | #endif |
129 | |
130 | #include "tst-timer4.c" |
131 | |