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/*-*- 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"
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;
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, 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 lets 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;
}
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