Add job control regression tests

test/apps/process/job_control.c

@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: MPL-2.0
+
+#include "../network/test.h"
+
+#include <unistd.h>
+#include <pty.h>
+#include <sys/wait.h>
+
+static pid_t sid, child;
+static int master, slave;
+
+FN_SETUP(openpty)
+{
+	CHECK(openpty(&master, &slave, NULL, NULL, NULL));
+}
+END_SETUP()
+
+FN_SETUP(run_in_new_session)
+{
+	int status;
+
+	if (CHECK(fork()) != 0) {
+		CHECK_WITH(wait(&status),
+			   WIFEXITED(status) && WEXITSTATUS(status) == 0);
+		exit(EXIT_SUCCESS);
+	}
+
+	sid = CHECK(setsid());
+
+	if ((child = CHECK(fork())) == 0) {
+		child = getpid();
+
+		// TODO: Linux allows to specify PIDs (instead of PGIDs) as
+		// parameters to `TIOCSPGRP`. We may want to support this as
+		// well. For more details, see:
+		// <https://elixir.bootlin.com/linux/v6.14.5/source/drivers/tty/tty_jobctrl.c#L434-L453>.
+		CHECK(setpgrp());
+	}
+
+	signal(SIGHUP, SIG_IGN);
+	signal(SIGTTIN, SIG_IGN);
+
+	// TODO: We should forbid some TTY operations (e.g., `TIOCSPGRP`) if
+	// the `SIGTTOU` signal is not blocked or ignored and the current
+	// process is not in the foreground process group. However, this is
+	// not currently implemented in Asterinas yet.
+	signal(SIGTTOU, SIG_IGN);
+}
+END_SETUP()
+
+// From now on, we'll run all the tests twice, once as a session leader
+// and once not as a session leader. Most tests will only work in one of
+// the two cases, so check at the beginning and skip the test if it's
+// not the expected case.
+static int is_leader(void)
+{
+	return getpid() == sid;
+}
+
+// TODO: Find a better way to synchronize between the two processes.
+#define __NAMED_BARRIER(name)              \
+	FN_SETUP(name)                     \
+	{                                  \
+		CHECK(usleep(100 * 1000)); \
+	}                                  \
+	END_SETUP()
+#define NAMED_BARRIER(name) __NAMED_BARRIER(__CONCAT(barrier, name))
+#define BARRIER(name) NAMED_BARRIER(__LINE__)
+
+FN_TEST(not_our_tty)
+{
+	pid_t arg;
+
+	// Operate on the controlling session
+
+	TEST_ERRNO(ioctl(master, TIOCNOTTY), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCNOTTY), ENOTTY);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCNOTTY), ENOTTY);
+
+	TEST_ERRNO(ioctl(master, TIOCGSID, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCGSID, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCGSID, &arg), ENOTTY);
+
+	// Operate on the foreground process group
+
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(master, TIOCGPGRP, &arg), arg == 0);
+	TEST_ERRNO(ioctl(slave, TIOCGPGRP, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCGPGRP, &arg), ENOTTY);
+
+	TEST_ERRNO(ioctl(master, TIOCSPGRP, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCSPGRP, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCSPGRP, &arg), ENOTTY);
+}
+END_TEST()
+
+FN_TEST(nonleader_set_tty)
+{
+	if (is_leader())
+		return;
+
+	// Only session leaders can use `TIOCSCTTY`, but we're not the leader
+	TEST_ERRNO(ioctl(master, TIOCSCTTY, 0), EPERM);
+	TEST_ERRNO(ioctl(slave, TIOCSCTTY, 0), EPERM);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCSCTTY, 0), EPERM);
+}
+END_TEST()
+
+BARRIER()
+
+FN_TEST(leader_set_unset_tty)
+{
+	pid_t arg;
+
+	if (!is_leader())
+		return;
+
+	// We can use `TIOCSCTTY` on the master PTY
+	TEST_SUCC(ioctl(master, TIOCSCTTY, 0));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(master, TIOCGSID, &arg), arg == sid);
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(slave, TIOCGSID, &arg), arg == sid);
+
+	// `TIOCSCTTY` on the same TTY will succeed
+	TEST_SUCC(ioctl(master, TIOCSCTTY, 0));
+	TEST_SUCC(ioctl(slave, TIOCSCTTY, 0));
+
+	// `TIOCSCTTY` on a different TTY will fail
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCSCTTY, 0), EPERM);
+
+	// `TIOCNOTTY` to clear the associated TTY
+	TEST_ERRNO(ioctl(master, TIOCNOTTY), ENOTTY);
+	TEST_SUCC(ioctl(slave, TIOCNOTTY));
+	TEST_ERRNO(ioctl(master, TIOCGSID, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCGSID, &arg), ENOTTY);
+
+	// We can also use `TIOCSCTTY` on the slave PTY
+	TEST_SUCC(ioctl(slave, TIOCSCTTY, 0));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(master, TIOCGSID, &arg), arg == sid);
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(slave, TIOCGSID, &arg), arg == sid);
+}
+END_TEST()
+
+BARRIER()
+
+FN_TEST(nonleader_unset_tty)
+{
+	if (is_leader())
+		return;
+
+	// Only session leaders can use `TIOCNOTTY`, but we're not the leader
+	TEST_ERRNO(ioctl(master, TIOCNOTTY), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCNOTTY), ENOTTY);
+	TEST_ERRNO(ioctl(STDIN_FILENO, TIOCNOTTY), ENOTTY);
+}
+END_TEST()
+
+FN_TEST(query_foreground)
+{
+	pid_t arg;
+
+	// All processes can use `TIOCGPGRP` on the master PTY
+	TEST_RES(ioctl(master, TIOCGPGRP, &arg), arg == sid);
+
+	// Only session leaders can use `TIOCGPGRP` on the slave PTY
+	if (is_leader())
+		TEST_RES(ioctl(slave, TIOCGPGRP, &arg), arg == sid);
+	else
+		TEST_ERRNO(ioctl(slave, TIOCGPGRP, &arg), ENOTTY);
+}
+END_TEST()
+
+BARRIER()
+
+FN_TEST(leader_set_foreground)
+{
+	pid_t arg;
+
+	if (!is_leader())
+		return;
+
+	// Only session leaders can use `TIOCSPGRP`, and we're the leader
+
+	arg = child;
+	TEST_SUCC(ioctl(master, TIOCSPGRP, &arg));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(slave, TIOCGPGRP, &arg), arg == child);
+
+	arg = sid;
+	TEST_SUCC(ioctl(master, TIOCSPGRP, &arg));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(slave, TIOCGPGRP, &arg), arg == sid);
+
+	arg = child;
+	TEST_SUCC(ioctl(slave, TIOCSPGRP, &arg));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(master, TIOCGPGRP, &arg), arg == child);
+
+	arg = sid;
+	TEST_SUCC(ioctl(slave, TIOCSPGRP, &arg));
+	arg = 0xdeadbeef;
+	TEST_RES(ioctl(master, TIOCGPGRP, &arg), arg == sid);
+}
+END_TEST()
+
+BARRIER()
+
+FN_TEST(nonleader_set_foreground)
+{
+	pid_t arg = child;
+
+	if (is_leader())
+		return;
+
+	// Only session leaders can use `TIOCSPGRP`, but we're not the leader
+
+	TEST_ERRNO(ioctl(master, TIOCSPGRP, &arg), ENOTTY);
+	TEST_ERRNO(ioctl(slave, TIOCSPGRP, &arg), ENOTTY);
+}
+END_TEST()
+
+FN_SETUP(cleanup)
+{
+	int status;
+
+	if (!is_leader())
+		return;
+
+	CHECK_WITH(wait(&status),
+		   WIFEXITED(status) && WEXITSTATUS(status) == 0);
+}
+END_SETUP()

test/apps/scripts/process.sh

@@ -30,6 +30,7 @@ mmap/mmap_and_fork
 mmap/mmap_shared_filebacked
 mmap/mmap_readahead
 process/group_session
+process/job_control
 pthread/pthread_test
 pty/open_pty
 sched/sched_attr