| Alexey Dobriyan | 5de3d40 | 2018-04-10 16:42:23 -0700 | [diff] [blame] | 1 | /* |
| Alexey Dobriyan | ee9294d | 2018-04-12 23:31:17 +0300 | [diff] [blame^] | 2 | * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com> |
| Alexey Dobriyan | 5de3d40 | 2018-04-10 16:42:23 -0700 | [diff] [blame] | 3 | * |
| 4 | * Permission to use, copy, modify, and distribute this software for any |
| 5 | * purpose with or without fee is hereby granted, provided that the above |
| 6 | * copyright notice and this permission notice appear in all copies. |
| 7 | * |
| 8 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 9 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 10 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 11 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 12 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 13 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 14 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 15 | */ |
| 16 | /* Test that /proc/loadavg correctly reports last pid in pid namespace. */ |
| 17 | #define _GNU_SOURCE |
| 18 | #include <errno.h> |
| 19 | #include <sched.h> |
| 20 | #include <sys/types.h> |
| 21 | #include <sys/stat.h> |
| 22 | #include <fcntl.h> |
| 23 | #include <unistd.h> |
| 24 | #include <sys/wait.h> |
| 25 | |
| 26 | int main(void) |
| 27 | { |
| 28 | pid_t pid; |
| 29 | int wstatus; |
| 30 | |
| 31 | if (unshare(CLONE_NEWPID) == -1) { |
| 32 | if (errno == ENOSYS || errno == EPERM) |
| 33 | return 2; |
| 34 | return 1; |
| 35 | } |
| 36 | |
| 37 | pid = fork(); |
| 38 | if (pid == -1) |
| 39 | return 1; |
| 40 | if (pid == 0) { |
| 41 | char buf[128], *p; |
| 42 | int fd; |
| 43 | ssize_t rv; |
| 44 | |
| 45 | fd = open("/proc/loadavg" , O_RDONLY); |
| 46 | if (fd == -1) |
| 47 | return 1; |
| 48 | rv = read(fd, buf, sizeof(buf)); |
| 49 | if (rv < 3) |
| 50 | return 1; |
| 51 | p = buf + rv; |
| 52 | |
| 53 | /* pid 1 */ |
| 54 | if (!(p[-3] == ' ' && p[-2] == '1' && p[-1] == '\n')) |
| 55 | return 1; |
| 56 | |
| 57 | pid = fork(); |
| 58 | if (pid == -1) |
| 59 | return 1; |
| 60 | if (pid == 0) |
| 61 | return 0; |
| 62 | if (waitpid(pid, NULL, 0) == -1) |
| 63 | return 1; |
| 64 | |
| 65 | lseek(fd, 0, SEEK_SET); |
| 66 | rv = read(fd, buf, sizeof(buf)); |
| 67 | if (rv < 3) |
| 68 | return 1; |
| 69 | p = buf + rv; |
| 70 | |
| 71 | /* pid 2 */ |
| 72 | if (!(p[-3] == ' ' && p[-2] == '2' && p[-1] == '\n')) |
| 73 | return 1; |
| 74 | |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | if (waitpid(pid, &wstatus, 0) == -1) |
| 79 | return 1; |
| 80 | if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) |
| 81 | return 0; |
| 82 | return 1; |
| 83 | } |