- signal(SIGHUP, fatal_sig_handler);
- signal(SIGINT, fatal_sig_handler);
- signal(SIGQUIT, fatal_sig_handler);
- signal(SIGILL, fatal_sig_handler);
- signal(SIGABRT, fatal_sig_handler);
- signal(SIGFPE, fatal_sig_handler);
- signal(SIGPIPE, fatal_sig_handler);
- signal(SIGALRM, fatal_sig_handler);
- signal(SIGTERM, fatal_sig_handler);
- signal(SIGSEGV, fatal_sig_handler);
- signal(SIGUSR1, fatal_sig_handler);
- signal(SIGUSR2, fatal_sig_handler);
+ if (pipe(pipefd) < 0) {
+ perror("pterm: pipe");
+ exit(1);
+ }
+ pid = fork();
+ if (pid < 0) {
+ perror("pterm: fork");
+ exit(1);
+ } else if (pid == 0) {
+ char display[128], buffer[128];
+ int dlen, ret;
+
+ close(pipefd[1]);
+ /*
+ * Now sit here until we receive a display name from the
+ * other end of the pipe, and then stamp utmp. Unstamp utmp
+ * again, and exit, when the pipe closes.
+ */
+
+ dlen = 0;
+ while (1) {
+
+ ret = read(pipefd[0], buffer, lenof(buffer));
+ if (ret <= 0) {
+ cleanup_utmp();
+ exit(0);
+ } else if (!pty_stamped_utmp) {
+ if (dlen < lenof(display))
+ memcpy(display+dlen, buffer,
+ min(ret, lenof(display)-dlen));
+ if (buffer[ret-1] == '\0') {
+ /*
+ * Now we have a display name. NUL-terminate
+ * it, and stamp utmp.
+ */
+ display[lenof(display)-1] = '\0';
+ /*
+ * Trap as many fatal signals as we can in the
+ * hope of having the best possible chance to
+ * clean up utmp before termination. We are
+ * unfortunately unprotected against SIGKILL,
+ * but that's life.
+ */
+ signal(SIGHUP, fatal_sig_handler);
+ signal(SIGINT, fatal_sig_handler);
+ signal(SIGQUIT, fatal_sig_handler);
+ signal(SIGILL, fatal_sig_handler);
+ signal(SIGABRT, fatal_sig_handler);
+ signal(SIGFPE, fatal_sig_handler);
+ signal(SIGPIPE, fatal_sig_handler);
+ signal(SIGALRM, fatal_sig_handler);
+ signal(SIGTERM, fatal_sig_handler);
+ signal(SIGSEGV, fatal_sig_handler);
+ signal(SIGUSR1, fatal_sig_handler);
+ signal(SIGUSR2, fatal_sig_handler);