/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2014 David Herrmann <dh.herrmann@gmail.com> systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include <errno.h> #include <locale.h> #include <string.h> #include <sys/wait.h> #include <unistd.h> #include "pty.h" #include "util.h" #include "signal-util.h" static const char sndmsg[] = "message\n"; static const char rcvmsg[] = "message\r\n"; static char rcvbuf[128]; static size_t rcvsiz = 0; static sd_event *event; static void run_child(Pty *pty) { ssize_t r, l; char buf[512]; r = read(0, buf, sizeof(buf)); assert_se((size_t)r == strlen(sndmsg)); assert_se(!strncmp(buf, sndmsg, r)); l = write(1, buf, r); assert_se(l == r); } static int pty_fn(Pty *pty, void *userdata, unsigned int ev, const void *ptr, size_t size) { switch (ev) { case PTY_DATA: assert_se(rcvsiz < strlen(rcvmsg) * 2); assert_se(rcvsiz + size < sizeof(rcvbuf)); memcpy(&rcvbuf[rcvsiz], ptr, size); rcvsiz += size; if (rcvsiz >= strlen(rcvmsg) * 2) { assert_se(rcvsiz == strlen(rcvmsg) * 2); assert_se(!memcmp(rcvbuf, rcvmsg, strlen(rcvmsg))); assert_se(!memcmp(&rcvbuf[strlen(rcvmsg)], rcvmsg, strlen(rcvmsg))); } break; case PTY_HUP: /* This is guaranteed to appear _after_ the input queues are * drained! */ assert_se(rcvsiz == strlen(rcvmsg) * 2); break; case PTY_CHILD: /* this may appear at any time */ break; default: assert_se(0); break; } /* if we got HUP _and_ CHILD, exit */ if (pty_get_fd(pty) < 0 && pty_get_child(pty) < 0) sd_event_exit(event, 0); return 0; } static void run_parent(Pty *pty) { int r; /* write message to pty, ECHO mode guarantees that we get it back * twice: once via ECHO, once from the run_child() fn */ assert_se(pty_write(pty, sndmsg, strlen(sndmsg)) >= 0); r = sd_event_loop(event); assert_se(r >= 0); } static void test_pty(void) { pid_t pid; Pty *pty = NULL; rcvsiz = 0; zero(rcvbuf); assert_se(sd_event_default(&event) >= 0); pid = pty_fork(&pty, event, pty_fn, NULL, 80, 25); assert_se(pid >= 0); if (pid == 0) { /* child */ run_child(pty); exit(0); } /* parent */ run_parent(pty); /* Make sure the PTY recycled the child; yeah, this is racy if the * PID was already reused; but that seems fine for a test. */ assert_se(waitpid(pid, NULL, WNOHANG) < 0 && errno == ECHILD); pty_unref(pty); sd_event_unref(event); } int main(int argc, char *argv[]) { unsigned int i; log_parse_environment(); log_open(); assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, -1) >= 0); /* Oh, there're ugly races in the TTY layer regarding HUP vs IN. Turns * out they appear only 10% of the time. I fixed all of them and * don't see them, anymore. But let's be safe and run this 1000 times * so we catch any new ones, in case they appear again. */ for (i = 0; i < 1000; ++i) test_pty(); return 0; }