3 files changed, 44 insertions, 0 deletions
diff --git a/src/user/app/shell/builtins.c b/src/user/app/shell/builtins.c
index 1a46003..d4de354 100644
--- a/src/user/app/shell/builtins.c
+++ b/src/user/app/shell/builtins.c
@@ -117,6 +117,14 @@ static void cmd_ls(int argc, char **argv) {
 	}
 }
 
+static void cmd_sleep(int argc, char **argv) {
+	if (argc < 2) {
+		eprintf("no arguments");
+		return;
+	}
+	_syscall_sleep(strtol(argv[1], NULL, 0) * 1000);
+}
+
 static void cmd_touch(int argc, char **argv) {
 	if (argc <= 1) {
 		eprintf("no arguments");
@@ -135,6 +143,7 @@ struct builtin builtins[] = {
 	{"echo", cmd_echo},
 	{"hexdump", cmd_hexdump},
 	{"ls", cmd_ls},
+	{"sleep", cmd_sleep},
 	{"touch", cmd_touch},
 	{NULL, NULL},
 };
diff --git a/src/user/app/tests/tests.c b/src/user/app/tests/tests.c
index d655ab9..5c40bcd 100644
--- a/src/user/app/tests/tests.c
+++ b/src/user/app/tests/tests.c
@@ -254,7 +254,37 @@ static void test_strtol(void) {
 	assert(!strcmp("hello", end));
 	assert(01234 == strtol("   01234hello", &end, 0));
 	assert(!strcmp("hello", end));
+}
+
+static void test_sleep(void) {
+	// TODO yet another of those fake tests that you have to verify by hand
+	if (!fork()) {
+		if (!fork()) {
+			_syscall_sleep(100);
+			printf("1\n");
+			_syscall_sleep(200);
+			printf("3\n");
+			_syscall_sleep(200);
+			printf("5\n");
+			_syscall_exit(0);
+		}
+		if (!fork()) {
+			printf("0\n");
+			_syscall_sleep(200);
+			printf("2\n");
+			_syscall_sleep(200);
+			printf("4\n");
+			/* get killed while asleep
+			* a peaceful death, i suppose. */
+			for (;;) _syscall_sleep(1000000000);
+		}
+		_syscall_await();
+		_syscall_exit(0);
+	}
 
+	/* this part checks if, after killing an asleep process, other processes can still wake up */
+	_syscall_sleep(600);
+	printf("6\n");
 }
 
 static void test_misc(void) {
@@ -276,6 +306,7 @@ int main(void) {
 	run_forked(test_execbuf);
 	run_forked(test_printf);
 	run_forked(test_strtol);
+	run_forked(test_sleep);
 	run_forked(test_misc);
 	return 1;
 }
diff --git a/src/user/lib/syscall.c b/src/user/lib/syscall.c
index 842b7b9..ffda454 100644
--- a/src/user/lib/syscall.c
+++ b/src/user/lib/syscall.c
@@ -58,6 +58,10 @@ long _syscall_pipe(handle_t __user user_ends[2], int flags) {
 	return _syscall(_SYSCALL_PIPE, (long)user_ends, (long)flags, 0, 0, 0);
 }
 
+void _syscall_sleep(long ms) {
+	return (void)_syscall(_SYSCALL_SLEEP, ms, 0, 0, 0, 0);
+}
+
 long _syscall_execbuf(void __user *buf, size_t len) {
 	return _syscall(_SYSCALL_EXECBUF, (long)buf, (long)len, 0, 0, 0);
 }