test/piggie: add tests for zombie/dead processes

Signed-off-by: Radostin Stoyanov <rstoyanov@fedoraproject.org>

Author: rst0git

test/Makefile

@@ -12,7 +12,7 @@ test-junit: test-imgs
 	bats -F junit checkpointctl.bats > junit.xml
 
 test-imgs: piggie/piggie
-	$(eval PID := $(shell export TEST_ENV=BAR TEST_ENV_EMPTY=; piggie/piggie --tcp-socket))
+	$(eval PID := $(shell export TEST_ENV=BAR TEST_ENV_EMPTY=; piggie/piggie --tcp-socket --zombie))
 	mkdir -p $@
 	$(CRIU) dump --tcp-established -v4 -o dump.log -D $@ -t $(PID) || cat $@/dump.log
 

test/checkpointctl.bats

@@ -386,9 +386,15 @@ function teardown() {
 	( cd "$TEST_TMP_DIR1" && tar cf "$TEST_TMP_DIR2"/test.tar . )
 	checkpointctl inspect "$TEST_TMP_DIR2"/test.tar --files
 	[ "$status" -eq 0 ]
+
 	[[ ${lines[11]} == *"[REG 0]"* ]]
 	[[ ${lines[25]} == *"[cwd]"* ]]
 	[[ ${lines[26]} == *"[root]"* ]]
+
+	[[ ${lines[27]} == *"[5 (Dead)]  piggie-zombie"* ]]
+	[[ ${lines[28]} == *"[6 (Stopped)]  stopped-child"* ]]
+	[[ ${lines[29]} == *"Open files"* ]]
+	[[ ${lines[33]} == *"[7]  alive-child"* ]]
 }
 
 @test "Run checkpointctl inspect with tar file and --files and missing files.img" {

test/piggie/piggie.c

@@ -26,8 +26,54 @@
 typedef struct {
 	char *log_file;
 	bool use_tcp_socket;
+	bool create_zombie;
 } opts_t;
 
+static void create_zombie(void)
+{
+	pid_t zombie_pid = fork();
+
+	if (zombie_pid < 0) {
+		perror("zombie: fork failed");
+		return;
+	}
+
+	if (zombie_pid == 0) {
+		/* This process will become the zombie */
+
+		prctl(PR_SET_NAME, "piggie-zombie");
+
+		/* First alive child */
+		pid_t c1 = fork();
+		if (c1 == 0) {
+			prctl(PR_SET_NAME, "stopped-child");
+			raise(SIGSTOP);   /* enters stopped task state */
+			while (1)
+				sleep(1);
+		}
+
+		/* Second alive child */
+		pid_t c2 = fork();
+		if (c2 == 0) {
+			prctl(PR_SET_NAME, "alive-child");
+			while (1)
+				sleep(1);
+		}
+
+		/*
+		 * Parent of the two children exits immediately.
+		 * Since *its* parent does not wait(), this
+		 * process becomes a zombie.
+		 */
+		_exit(0);
+	}
+
+	/*
+	 * Original parent intentionally does NOT wait()
+	 * zombie_pid stays as a zombie.
+	 */
+}
+
 void run_tcp_server(void)
 {
 	int server_socket, client_socket, ret;
@@ -192,6 +238,10 @@ static int do_test(void *opts_ptr)
 		run_tcp_client();
 	}
 
+	if (opts->create_zombie) {
+		create_zombie();
+	}
+
 	while (1) {
 		sleep(1);
 		printf("%d\n", i++);
@@ -223,6 +273,12 @@ static int parse_options(int argc, char **argv, bool *usage_error, opts_t *opts)
 			continue;
 		}
 
+		if (!strcmp(argv[i], "--zombie") || !strcmp(argv[i], "-z")) {
+			opts->create_zombie = true;
+			i++;
+			continue;
+		}
+
 		printf("Unknown option: %s\n", argv[i]);
 		*usage_error = true;
 		goto out;
@@ -242,7 +298,7 @@ int main(int argc, char **argv) {
 
 	ret = parse_options(argc, argv, &usage_error, &opts);
 	if (ret) {
-		fprintf(stderr, "Usage: %s -o/--log-file <log_file> [-t/--tcp-socket]\n", argv[0]);
+		fprintf(stderr, "Usage: %s -o/--log-file <log_file> [-t/--tcp-socket] [-z|--zombie]\n", argv[0]);
 		return (usage_error != false);
 	}