#define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> #include <signal.h> #include <limits.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <fcntl.h> #include <linux/unistd.h> #include <linux/kcmp.h> #include <sys/syscall.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/wait.h> static long sys_kcmp(int pid1, int pid2, int type, int fd1, int fd2) { return syscall(__NR_kcmp, pid1, pid2, type, fd1, fd2); } int main(int argc, char **argv) { const char kpath[] = "kcmp-test-file"; int pid1, pid2; int fd1, fd2; int status; fd1 = open(kpath, O_RDWR | O_CREAT | O_TRUNC, 0644); pid1 = getpid(); if (fd1 < 0) { perror("Can't create file"); exit(1); } pid2 = fork(); if (pid2 < 0) { perror("fork failed"); exit(1); } if (!pid2) { int pid2 = getpid(); int ret; fd2 = open(kpath, O_RDWR, 0644); if (fd2 < 0) { perror("Can't open file"); exit(1); } /* An example of output and arguments */ printf("pid1: %6d pid2: %6d FD: %2ld FILES: %2ld VM: %2ld " "FS: %2ld SIGHAND: %2ld IO: %2ld SYSVSEM: %2ld " "INV: %2ld\n", pid1, pid2, sys_kcmp(pid1, pid2, KCMP_FILE, fd1, fd2), sys_kcmp(pid1, pid2, KCMP_FILES, 0, 0), sys_kcmp(pid1, pid2, KCMP_VM, 0, 0), sys_kcmp(pid1, pid2, KCMP_FS, 0, 0), sys_kcmp(pid1, pid2, KCMP_SIGHAND, 0, 0), sys_kcmp(pid1, pid2, KCMP_IO, 0, 0), sys_kcmp(pid1, pid2, KCMP_SYSVSEM, 0, 0), /* This one should fail */ sys_kcmp(pid1, pid2, KCMP_TYPES + 1, 0, 0)); /* This one should return same fd */ ret = sys_kcmp(pid1, pid2, KCMP_FILE, fd1, fd1); if (ret) { printf("FAIL: 0 expected but %d returned (%s)\n", ret, strerror(errno)); ret = -1; } else printf("PASS: 0 returned as expected\n"); /* Compare with self */ ret = sys_kcmp(pid1, pid1, KCMP_VM, 0, 0); if (ret) { printf("FAIL: 0 expected but %d returned (%s)\n", ret, strerror(errno)); ret = -1; } else printf("PASS: 0 returned as expected\n"); exit(ret); } waitpid(pid2, &status, P_ALL); return 0; }