| /* |
| * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com> |
| * |
| * Permission to use, copy, modify, and distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| */ |
| /* Test that /proc/loadavg correctly reports last pid in pid namespace. */ |
| #define _GNU_SOURCE |
| #include <errno.h> |
| #include <sched.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <sys/wait.h> |
| |
| int main(void) |
| { |
| pid_t pid; |
| int wstatus; |
| |
| if (unshare(CLONE_NEWPID) == -1) { |
| if (errno == ENOSYS || errno == EPERM) |
| return 2; |
| return 1; |
| } |
| |
| pid = fork(); |
| if (pid == -1) |
| return 1; |
| if (pid == 0) { |
| char buf[128], *p; |
| int fd; |
| ssize_t rv; |
| |
| fd = open("/proc/loadavg" , O_RDONLY); |
| if (fd == -1) |
| return 1; |
| rv = read(fd, buf, sizeof(buf)); |
| if (rv < 3) |
| return 1; |
| p = buf + rv; |
| |
| /* pid 1 */ |
| if (!(p[-3] == ' ' && p[-2] == '1' && p[-1] == '\n')) |
| return 1; |
| |
| pid = fork(); |
| if (pid == -1) |
| return 1; |
| if (pid == 0) |
| return 0; |
| if (waitpid(pid, NULL, 0) == -1) |
| return 1; |
| |
| lseek(fd, 0, SEEK_SET); |
| rv = read(fd, buf, sizeof(buf)); |
| if (rv < 3) |
| return 1; |
| p = buf + rv; |
| |
| /* pid 2 */ |
| if (!(p[-3] == ' ' && p[-2] == '2' && p[-1] == '\n')) |
| return 1; |
| |
| return 0; |
| } |
| |
| if (waitpid(pid, &wstatus, 0) == -1) |
| return 1; |
| if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) |
| return 0; |
| return 1; |
| } |
