render/gbm_allocator: duplicate drm fd during creation process

include/render/gbm_allocator.h

@@ -26,7 +26,7 @@ struct wlr_gbm_allocator {
 /**
  * Creates a new GBM allocator from a DRM FD.
  *
- * Takes ownership over the FD.
+ * Does not take ownership over the FD.
  */
 struct wlr_allocator *wlr_gbm_allocator_create(int drm_fd);
 

render/allocator.c

@@ -1,6 +1,5 @@
 #define _POSIX_C_SOURCE 200809L
 #include <assert.h>
-#include <fcntl.h>
 #include <stdlib.h>
 #include <wlr/util/log.h>
 #include <xf86drm.h>
@@ -29,10 +28,7 @@ struct wlr_allocator *allocator_autocreate_with_drm_fd(
 	if ((backend_caps & gbm_caps) && (renderer_caps & gbm_caps)
 			&& drm_fd != -1) {
 		wlr_log(WLR_DEBUG, "Trying to create gbm allocator");
-		int fd = fcntl(drm_fd, F_DUPFD_CLOEXEC, 0);
-		if (fd < 0) {
-			wlr_log(WLR_ERROR, "fcntl(F_DUPFD_CLOEXEC) failed");
-		} else if ((alloc = wlr_gbm_allocator_create(fd)) != NULL) {
+		if ((alloc = wlr_gbm_allocator_create(drm_fd)) != NULL) {
 			return alloc;
 		}
 		wlr_log(WLR_DEBUG, "Failed to create gbm allocator");

render/gbm_allocator.c

@@ -159,7 +159,13 @@ static struct wlr_gbm_allocator *get_gbm_alloc_from_alloc(
 	return (struct wlr_gbm_allocator *)alloc;
 }
 
-struct wlr_allocator *wlr_gbm_allocator_create(int fd) {
+struct wlr_allocator *wlr_gbm_allocator_create(int drm_fd) {
+	int fd = fcntl(drm_fd, F_DUPFD_CLOEXEC, 0);
+	if (fd < 0) {
+		wlr_log(WLR_ERROR, "fcntl(F_DUPFD_CLOEXEC) failed");
+		return NULL;
+	}
+
 	uint64_t cap;
 	if (drmGetCap(fd, DRM_CAP_PRIME, &cap) ||
 			!(cap & DRM_PRIME_CAP_EXPORT)) {