Avoid SOCK_CLOEXEC on Darwin

Signed-off-by: Torrekie Gen <me@torrekie.dev>

src/wayland-os.c

@@ -74,18 +74,20 @@ int
 wl_os_socket_cloexec(int domain, int type, int protocol)
 {
 	int fd;
-
+#if !defined(__APPLE__)
+	/* It is ok to bypass this logic on Darwin,
+	   FD_CLOEXEC will be set by set_cloexec_or_close() */
 	fd = wl_socket(domain, type | SOCK_CLOEXEC, protocol);
 	if (fd >= 0)
 		return fd;
 	if (errno != EINVAL)
 		return -1;
-
+#endif
 	fd = wl_socket(domain, type, protocol);
 	return set_cloexec_or_close(fd);
 }
 
-#if defined(__FreeBSD__)
+#if defined(LOCAL_PEERCRED)
 int
 wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
 {
@@ -101,6 +103,14 @@ wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
 #if HAVE_XUCRED_CR_PID
 	/* Since https://cgit.freebsd.org/src/commit/?id=c5afec6e895a */
 	*pid = ucred.cr_pid;
+#elif defined(LOCAL_PEERPID)
+	/* Try LOCAL_PEERPID if no cr_pid in xucred */
+	size_t pid_size;
+	pid_t peerpid;
+	if (getsockopt(sockfd, SOL_LOCAL, LOCAL_PEERPID, &peerpid, &pid_size))
+		*pid = peerpid;
+	else
+		*pid = 0;
 #else
 	*pid = 0;
 #endif
@@ -178,13 +188,16 @@ recvmsg_cloexec_fallback(int sockfd, struct msghdr *msg, int flags)
 ssize_t
 wl_os_recvmsg_cloexec(int sockfd, struct msghdr *msg, int flags)
 {
-#if HAVE_BROKEN_MSG_CMSG_CLOEXEC
+#if HAVE_BROKEN_MSG_CMSG_CLOEXEC || defined(__APPLE__)
 	/*
 	 * FreeBSD had a broken implementation of MSG_CMSG_CLOEXEC between 2015
 	 * and 2021, so we have to use the non-MSG_CMSG_CLOEXEC fallback
 	 * directly when compiling against a version that does not include the
 	 * fix (https://cgit.freebsd.org/src/commit/?id=6ceacebdf52211).
 	 */
+	/*
+	 * Darwin has no MSG_CMSG_CLOEXEC, so use fallback too.
+	 */
 #pragma message("Using fallback directly since MSG_CMSG_CLOEXEC is broken.")
 #else
 	ssize_t len;
@@ -220,7 +233,7 @@ wl_os_accept_cloexec(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
 {
 	int fd;
 
-#ifdef HAVE_ACCEPT4
+#if defined(HAVE_ACCEPT4) && !defined(__APPLE__)
 	fd = accept4(sockfd, addr, addrlen, SOCK_CLOEXEC);
 	if (fd >= 0)
 		return fd;

tests/client-test.c

@@ -97,7 +97,13 @@ TEST(client_destroy_listener)
 	bool user_data_destroyed = false;
 	int s[2];
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);
@@ -184,7 +190,13 @@ TEST(client_destroy_removes_link)
 	struct client_destroy_listener destroy_listener;
 	int s[2];
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);

tests/connection-test.c

@@ -48,7 +48,13 @@ setup(int *s)
 {
 	struct wl_connection *connection;
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 
 	connection = wl_connection_create(s[0], WL_BUFFER_DEFAULT_MAX_SIZE);
 	assert(connection);
@@ -181,8 +187,14 @@ struct marshal_data {
 static void
 setup_marshal_data(struct marshal_data *data)
 {
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX,
 			  SOCK_STREAM | SOCK_CLOEXEC, 0, data->s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM , 0, data->s) == 0);
+	assert(set_cloexec_or_close(data->s[0]) != -1);
+	assert(set_cloexec_or_close(data->s[1]) != -1);
+#endif
 	data->read_connection = wl_connection_create(data->s[0],
 						     WL_BUFFER_DEFAULT_MAX_SIZE);
 	assert(data->read_connection);
@@ -885,7 +897,13 @@ TEST(request_bogus_size)
 	for (bogus_size = 11; bogus_size >= 0; bogus_size--) {
 		fprintf(stderr, "* bogus size %d\n", bogus_size);
 
+#ifdef SOCK_CLOEXEC
 		assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+		assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+		assert(set_cloexec_or_close(s[0]) != -1);
+		assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 		display = wl_display_create();
 		assert(display);
 		client = wl_client_create(display, s[0]);

tests/os-wrappers-test.c

@@ -23,6 +23,8 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
+ /* This test should be skipped on Darwin (as of 2024) */
+#ifndef __APPLE__
 #include "../config.h"
 
 #define _GNU_SOURCE
@@ -387,5 +389,5 @@ TEST(os_wrappers_epoll_create_cloexec_fallback)
 	init_fallbacks(1);
 	do_os_wrappers_epoll_create_cloexec(2);
 }
-
+#endif /* __APPLE__ */
 /* FIXME: add tests for wl_os_accept_cloexec() */

tests/resources-test.c

@@ -40,7 +40,14 @@ TEST(create_resource_tst)
 	int s[2];
 	uint32_t id;
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
+
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);
@@ -111,7 +118,13 @@ TEST(destroy_res_tst)
 		.notify = &destroy_notify
 	};
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);
@@ -159,7 +172,13 @@ TEST(create_resource_with_same_id)
 	int s[2];
 	uint32_t id;
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);
@@ -243,7 +262,13 @@ TEST(resource_destroy_iteration)
 		.notify = &resource_destroy_notify
 	};
 
+#ifdef SOCK_CLOEXEC
 	assert(socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, s) == 0);
+#else
+	assert(socketpair(AF_UNIX, SOCK_STREAM, 0, s) == 0);
+	assert(set_cloexec_or_close(s[0]) != -1);
+	assert(set_cloexec_or_close(s[1]) != -1);
+#endif
 	display = wl_display_create();
 	assert(display);
 	client = wl_client_create(display, s[0]);

tests/test-helpers.c

@@ -88,6 +88,30 @@ count_open_fds(void)
 	/* return the current number of entries */
 	return size / sizeof(struct kinfo_file);
 }
+#elif defined(__APPLE__)
+#include <libproc.h>
+
+/* 
+ * On Darwin, use libproc API to get fds of a PID
+ */
+int
+count_open_fds(void)
+{
+	int buffer_size, buffer_used;
+	pid_t pid = getpid();
+	int nfds;
+	struct proc_fdinfo *fdinfo;
+
+	buffer_size = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, 0, 0);
+	fdinfo = malloc(buffer_size);
+
+	buffer_used = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, fdinfo, buffer_size);
+	assert(buffer_used > 0 && "proc_pidinfo PROC_PIDLISTFDS failed.");
+
+	nfds = buffer_used / PROC_PIDLISTFD_SIZE;
+	free(fdinfo);
+	return nfds;
+}
 #else
 int
 count_open_fds(void)

tests/test-runner.c

@@ -63,7 +63,12 @@ static int timeouts_enabled = 1;
 /* set to one if the output goes to the terminal */
 static int is_atty = 0;
 
+#if __APPLE__
+extern const struct test __start_test_section __asm("section$start$__DATA$test_section");
+extern const struct test __stop_test_section __asm("section$end$__DATA$test_section");
+#else
 extern const struct test __start_test_section, __stop_test_section;
+#endif
 
 static const struct test *
 find_test(const char *name)
@@ -308,6 +313,23 @@ is_debugger_attached(void)
 
 	return rc;
 }
+#elif defined(__APPLE__)
+#include <sys/sysctl.h>
+/* https://stackoverflow.com/a/2200786 */
+static int
+is_debugger_attached(void)
+{
+	int ret;
+	int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, getpid() };
+	struct kinfo_proc info;
+	size_t size;
+
+	info.kp_proc.p_flag = 0;
+	ret = sysctl(mib, sizeof(mib) / sizeof(*mib), &info, &size, NULL, 0);
+	assert(ret == 0);
+
+	return ( (info.kp_proc.p_flag & P_TRACED) != 0 );
+}
 #else
 static int
 is_debugger_attached(void)

tests/test-runner.h

@@ -37,11 +37,17 @@ struct test {
 	int must_fail;
 } __attribute__ ((aligned (16)));
 
+#if __APPLE__
+#define TEST_SECTION "__DATA,test_section"
+#else
+#define TEST_SECTION "test_section"
+#endif
+
 #define TEST(name)							\
 	static void name(void);						\
 									\
 	const struct test test##name					\
-		 __attribute__ ((used, section ("test_section"))) = {	\
+		 __attribute__ ((used, section (TEST_SECTION))) = {	\
 		#name, name, 0						\
 	};								\
 									\
@@ -51,7 +57,7 @@ struct test {
 	static void name(void);						\
 									\
 	const struct test test##name					\
-		 __attribute__ ((used, section ("test_section"))) = {	\
+		 __attribute__ ((used, section (TEST_SECTION))) = {	\
 		#name, name, 1						\
 	};								\
 									\
@@ -93,3 +99,28 @@ test_disable_coredumps(void);
 	} while (0);
 
 #endif
+
+/* For systems without SOCK_CLOEXEC */
+#include <fcntl.h>
+__attribute__((used))
+static int
+set_cloexec_or_close(int fd)
+{
+	long flags;
+
+	if (fd == -1)
+		return -1;
+
+	flags = fcntl(fd, F_GETFD);
+	if (flags == -1)
+		goto err;
+
+	if (fcntl(fd, F_SETFD, flags | FD_CLOEXEC) == -1)
+		goto err;
+
+	return fd;
+
+err:
+	close(fd);
+	return -1;
+}