Stop remembering the drm fd in child.

include/session/direct-ipc.h

@@ -4,8 +4,8 @@
 #include <sys/types.h>
 
 int direct_ipc_open(int sock, const char *path);
-void direct_ipc_setmaster(int sock);
-void direct_ipc_dropmaster(int sock);
+void direct_ipc_setmaster(int sock, int fd);
+void direct_ipc_dropmaster(int sock, int fd);
 void direct_ipc_finish(int sock, pid_t pid);
 int direct_ipc_start(pid_t *pid_out);
 

session/direct-ipc.c

@@ -116,7 +116,7 @@ static void communicate(int sock) {
 	int drm_fd = -1;
 	bool running = true;
 
-	while (running && recv_msg(sock, NULL, &msg, sizeof(msg)) >= 0) {
+	while (running && recv_msg(sock, &drm_fd, &msg, sizeof(msg)) >= 0) {
 		switch (msg.type) {
 		case MSG_OPEN:
 			errno = 0;
@@ -140,29 +140,24 @@ static void communicate(int sock) {
 				goto error;
 			}
 
-			if (maj == DRM_MAJOR) {
-				if (drmSetMaster(fd)) {
-					ret = errno;
-				} else {
-					drm_fd = fd;
-				}
+			if (maj == DRM_MAJOR && drmSetMaster(fd)) {
+				ret = errno;
 			}
 error:
 			send_msg(sock, ret ? -1 : fd, &ret, sizeof(ret));
-
-			if (fd != drm_fd) {
-				close(fd);
-			}
+			close(fd);
 
 			break;
 
 		case MSG_SETMASTER:
 			drmSetMaster(drm_fd);
+			close(drm_fd);
 			send_msg(sock, -1, NULL, 0);
 			break;
 
 		case MSG_DROPMASTER:
 			drmDropMaster(drm_fd);
+			close(drm_fd);
 			send_msg(sock, -1, NULL, 0);
 			break;
 
@@ -173,7 +168,6 @@ error:
 		}
 	}
 
-	close(drm_fd);
 	close(sock);
 }
 
@@ -189,17 +183,17 @@ int direct_ipc_open(int sock, const char *path) {
 	return err ? -err : fd;
 }
 
-void direct_ipc_setmaster(int sock) {
+void direct_ipc_setmaster(int sock, int fd) {
 	struct msg msg = { .type = MSG_SETMASTER };
 
-	send_msg(sock, -1, &msg, sizeof(msg));
+	send_msg(sock, fd, &msg, sizeof(msg));
 	recv_msg(sock, NULL, NULL, 0);
 }
 
-void direct_ipc_dropmaster(int sock) {
+void direct_ipc_dropmaster(int sock, int fd) {
 	struct msg msg = { .type = MSG_DROPMASTER };
 
-	send_msg(sock, -1, &msg, sizeof(msg));
+	send_msg(sock, fd, &msg, sizeof(msg));
 	recv_msg(sock, NULL, NULL, 0);
 }
 

session/direct.c

@@ -65,7 +65,7 @@ static void direct_session_close(struct wlr_session *base, int fd) {
 	}
 
 	if (major(st.st_rdev) == DRM_MAJOR) {
-		direct_ipc_dropmaster(session->sock);
+		direct_ipc_dropmaster(session->sock, session->base.drm_fd);
 		session->base.drm_fd = -1;
 	} else if (major(st.st_rdev) == INPUT_MAJOR) {
 		ioctl(fd, EVIOCREVOKE, 0);
@@ -109,11 +109,11 @@ static int vt_handler(int signo, void *data) {
 	if (session->base.active) {
 		session->base.active = false;
 		wl_signal_emit(&session->base.session_signal, session);
-		direct_ipc_dropmaster(session->sock);
+		direct_ipc_dropmaster(session->sock, session->base.drm_fd);
 		ioctl(session->tty_fd, VT_RELDISP, 1);
 	} else {
 		ioctl(session->tty_fd, VT_RELDISP, VT_ACKACQ);
-		direct_ipc_setmaster(session->sock);
+		direct_ipc_setmaster(session->sock, session->base.drm_fd);
 		session->base.active = true;
 		wl_signal_emit(&session->base.session_signal, session);
 	}