Add regression tests for exit()

test/apps/Makefile

@@ -18,6 +18,7 @@ TEST_APPS := \
 	epoll \
 	eventfd2 \
 	execve \
+	exit \
 	fdatasync \
 	file_io \
 	fork \

test/apps/exit/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: MPL-2.0
+
+include ../test_common.mk
+
+EXTRA_C_FLAGS := -static -lpthread

test/apps/exit/exit_code.c

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: MPL-2.0
+
+#include "../network/test.h"
+
+#include <pthread.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+
+struct exit_info {
+	int should_use_exit_group;
+	int should_exit_master_first;
+};
+
+static void *thread_slave(void *info_)
+{
+	struct exit_info *info = info_;
+
+	if (info->should_exit_master_first) {
+		if (info->should_use_exit_group)
+			sleep(3600);
+		usleep(200 * 1000);
+	}
+
+	if (info->should_use_exit_group)
+		syscall(SYS_exit_group, 55);
+	else
+		syscall(SYS_exit, 66);
+
+	exit(-1);
+}
+
+static void *thread_master(void *info_)
+{
+	struct exit_info *info = info_;
+	pthread_t tid;
+
+	CHECK(pthread_create(&tid, NULL, &thread_slave, info));
+
+	if (!info->should_exit_master_first) {
+		if (info->should_use_exit_group)
+			sleep(3600);
+		usleep(200 * 1000);
+	}
+
+	if (info->should_use_exit_group)
+		syscall(SYS_exit_group, 77);
+	else
+		syscall(SYS_exit, 88);
+
+	exit(-1);
+}
+
+FN_TEST(exit_two_threads)
+{
+	struct exit_info info;
+	int stat;
+
+	info.should_use_exit_group = 1;
+	info.should_exit_master_first = 1;
+	if (CHECK(fork()) == 0) {
+		thread_master(&info);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 77);
+
+	info.should_use_exit_group = 1;
+	info.should_exit_master_first = 0;
+	if (CHECK(fork()) == 0) {
+		thread_master(&info);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 55);
+
+	info.should_use_exit_group = 0;
+	info.should_exit_master_first = 1;
+	if (CHECK(fork()) == 0) {
+		thread_master(&info);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 66);
+
+	info.should_use_exit_group = 0;
+	info.should_exit_master_first = 0;
+	if (CHECK(fork()) == 0) {
+		thread_master(&info);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 88);
+}
+END_TEST()

test/apps/exit/exit_procfs.c

@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: MPL-2.0
+
+#include "../network/test.h"
+
+#include <unistd.h>
+#include <pthread.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+
+#define EXIT_PARENT_FIRST ((void *)1)
+#define EXIT_CHILD_FIRST ((void *)2)
+
+// TODO: Use `system` directly after we implement `vfork`.
+static int mini_system(const char *cmd)
+{
+	int pid;
+	int stat;
+
+	pid = CHECK(fork());
+
+	if (pid == 0) {
+		CHECK(execlp("sh", "sh", "-c", cmd, NULL));
+		exit(-1);
+	}
+
+	CHECK_WITH(waitpid(pid, &stat, 0), _ret == pid && WIFEXITED(stat));
+
+	return WEXITSTATUS(stat);
+}
+
+static void *thread_slave(void *arg)
+{
+	if (arg == EXIT_CHILD_FIRST) {
+		CHECK_WITH(
+			mini_system(
+				"cat /proc/$PPID/status | grep '^Threads:\t2$'"),
+			_ret == 0);
+
+		syscall(SYS_exit, 0);
+	} else {
+		// When the main thread exits, it becomes a zombie, so we still
+		// have two threads.
+		usleep(200 * 1000);
+		CHECK_WITH(
+			mini_system(
+				"cat /proc/$PPID/status | grep '^Threads:\t2$'"),
+			_ret == 0);
+
+		syscall(SYS_exit, 0);
+	}
+
+	exit(-1);
+}
+
+static void thread_master(void *arg)
+{
+	pthread_t tid;
+
+	CHECK(pthread_create(&tid, NULL, &thread_slave, arg));
+
+	if (arg == EXIT_PARENT_FIRST) {
+		CHECK_WITH(
+			mini_system(
+				"cat /proc/$PPID/status | grep '^Threads:\t2$'"),
+			_ret == 0);
+
+		syscall(SYS_exit, 0);
+	} else {
+		// When a non-main thread exits, its resource is automatically
+		// freed, so we only have one thread.
+		usleep(200 * 1000);
+		CHECK_WITH(
+			mini_system(
+				"cat /proc/$PPID/status | grep '^Threads:\t1$'"),
+			_ret == 0);
+
+		syscall(SYS_exit, 0);
+	}
+
+	exit(-1);
+}
+
+FN_TEST(exit_procfs)
+{
+	int stat;
+
+	if (CHECK(fork()) == 0) {
+		thread_master(EXIT_CHILD_FIRST);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 0);
+
+	if (CHECK(fork()) == 0) {
+		thread_master(EXIT_PARENT_FIRST);
+	}
+	TEST_RES(wait(&stat), WIFEXITED(stat) && WEXITSTATUS(stat) == 0);
+}
+END_TEST()

test/apps/scripts/process.sh

@@ -15,6 +15,8 @@ clone3/clone_no_exit_signal
 clone3/clone_process
 cpu_affinity/cpu_affinity
 execve/execve
+exit/exit_code
+exit/exit_procfs
 eventfd2/eventfd2
 fork/fork
 fork_c/fork