xrt: Make xrt_compositor::create_swapchain return xrt_result_t

src/xrt/compositor/client/comp_gl_client.c

@@ -249,11 +249,13 @@ vk_format_to_gl(int64_t format)
 	}
 }
 
-static struct xrt_swapchain *
+static xrt_result_t
 client_gl_swapchain_create(struct xrt_compositor *xc,
-                           struct xrt_swapchain_create_info *info)
+                           struct xrt_swapchain_create_info *info,
+                           struct xrt_swapchain **out_xsc)
 {
 	struct client_gl_compositor *c = client_gl_compositor(xc);
+	xrt_result_t xret = XRT_SUCCESS;
 
 	if (info->array_size > 1) {
 		const char *version_str = (const char *)glGetString(GL_VERSION);
@@ -262,25 +264,27 @@ client_gl_swapchain_create(struct xrt_compositor *xc,
 			        "%s - only one array layer is supported with "
 			        "OpenGL ES 2\n",
 			        __func__);
-			return NULL;
+			return XRT_ERROR_OPENGL;
 		}
 	}
 
 	int64_t vk_format = gl_format_to_vk(info->format);
 	if (vk_format == 0) {
 		fprintf(stderr, "%s - Invalid format!\n", __func__);
-		return NULL;
+		return XRT_ERROR_VULKAN;
 	}
 
-	struct xrt_swapchain_create_info vk_info = *info;
+	struct xrt_swapchain_create_info xinfo = *info;
-	vk_info.format = vk_format;
+	xinfo.format = vk_format;
-	struct xrt_swapchain_native *xscn =
+	struct xrt_swapchain_native *xscn = NULL;
-	    xrt_comp_native_create_swapchain(c->xcn, &vk_info);
+	xret = xrt_comp_native_create_swapchain(c->xcn, &xinfo, &xscn);
 
 
-	if (xscn == NULL) {
+	if (xret != XRT_SUCCESS) {
-		return NULL;
+		return xret;
 	}
+	assert(xscn != NULL);
+
 	struct xrt_swapchain *xsc = &xscn->base;
 
 	struct client_gl_swapchain *sc =
@@ -333,7 +337,8 @@ client_gl_swapchain_create(struct xrt_compositor *xc,
 	                                    : GL_TEXTURE_2D_ARRAY,
 	              prev_texture);
 
-	return &sc->base.base;
+	*out_xsc = &sc->base.base;
+	return XRT_SUCCESS;
 }
 
 static xrt_result_t

src/xrt/compositor/client/comp_vk_client.c

@@ -284,25 +284,29 @@ client_vk_compositor_layer_commit(struct xrt_compositor *xc, int64_t frame_id)
 	return xrt_comp_layer_commit(&c->xcn->base, frame_id);
 }
 
-static struct xrt_swapchain *
+static xrt_result_t
 client_vk_swapchain_create(struct xrt_compositor *xc,
-                           struct xrt_swapchain_create_info *info)
+                           struct xrt_swapchain_create_info *info,
+                           struct xrt_swapchain **out_xsc)
 {
 	struct client_vk_compositor *c = client_vk_compositor(xc);
 	VkCommandBuffer cmd_buffer;
 	VkResult ret;
+	xrt_result_t xret;
 
-	struct xrt_swapchain_native *xscn =
+	struct xrt_swapchain_native *xscn = NULL;
-	    xrt_comp_native_create_swapchain(c->xcn, info);
+	xret = xrt_comp_native_create_swapchain(c->xcn, info, &xscn);
 
-	if (xscn == NULL) {
+	if (xret != XRT_SUCCESS) {
-		return NULL;
+		return xret;
 	}
+	assert(xscn != NULL);
+
 	struct xrt_swapchain *xsc = &xscn->base;
 
 	ret = vk_init_cmd_buffer(&c->vk, &cmd_buffer);
 	if (ret != VK_SUCCESS) {
-		return NULL;
+		return XRT_ERROR_VULKAN;
 	}
 
 	VkImageSubresourceRange subresource_range = {
@@ -331,7 +335,7 @@ client_vk_swapchain_create(struct xrt_compositor *xc,
 
 
 		if (ret != VK_SUCCESS) {
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 
 		/*
@@ -348,7 +352,7 @@ client_vk_swapchain_create(struct xrt_compositor *xc,
 
 	ret = vk_submit_cmd_buffer(&c->vk, cmd_buffer);
 	if (ret != VK_SUCCESS) {
-		return NULL;
+		return XRT_ERROR_FAILED_TO_SUBMIT_VULKAN_COMMANDS;
 	}
 
 	// Prerecord command buffers for swapchain image ownership/layout
@@ -356,11 +360,11 @@ client_vk_swapchain_create(struct xrt_compositor *xc,
 	for (uint32_t i = 0; i < xsc->num_images; i++) {
 		ret = vk_init_cmd_buffer(&c->vk, &sc->acquire[i]);
 		if (ret != VK_SUCCESS) {
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 		ret = vk_init_cmd_buffer(&c->vk, &sc->release[i]);
 		if (ret != VK_SUCCESS) {
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 
 		VkImageSubresourceRange subresource_range = {
@@ -425,17 +429,19 @@ client_vk_swapchain_create(struct xrt_compositor *xc,
 		if (ret != VK_SUCCESS) {
 			VK_ERROR(vk, "vkEndCommandBuffer: %s",
 			         vk_result_string(ret));
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 		ret = c->vk.vkEndCommandBuffer(sc->release[i]);
 		if (ret != VK_SUCCESS) {
 			VK_ERROR(vk, "vkEndCommandBuffer: %s",
 			         vk_result_string(ret));
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 	}
 
-	return &sc->base.base;
+	*out_xsc = &sc->base.base;
+
+	return XRT_SUCCESS;
 }
 
 struct client_vk_compositor *

src/xrt/compositor/main/comp_compositor.h

@@ -271,9 +271,10 @@ comp_compositor_garbage_collect(struct comp_compositor *c);
  *
  * @public @memberof comp_compositor
  */
-struct xrt_swapchain *
+xrt_result_t
 comp_swapchain_create(struct xrt_compositor *xc,
-                      struct xrt_swapchain_create_info *info);
+                      struct xrt_swapchain_create_info *info,
+                      struct xrt_swapchain **out_xsc);
 
 /*!
  * Swapchain destruct is delayed until it is safe to destroy them, this function

src/xrt/compositor/main/comp_swapchain.c

@@ -221,9 +221,10 @@ err_image:
  *
  */
 
-struct xrt_swapchain *
+xrt_result_t
 comp_swapchain_create(struct xrt_compositor *xc,
-                      struct xrt_swapchain_create_info *info)
+                      struct xrt_swapchain_create_info *info,
+                      struct xrt_swapchain **out_xsc)
 {
 	struct comp_compositor *c = comp_compositor(xc);
 	VkCommandBuffer cmd_buffer;
@@ -259,7 +260,7 @@ comp_swapchain_create(struct xrt_compositor *xc,
 			//! @todo memory leak of image fds and swapchain
 			// see
 			// https://gitlab.freedesktop.org/monado/monado/issues/20
-			return NULL;
+			return XRT_ERROR_VULKAN;
 		}
 
 		vk_create_sampler(&c->vk, &sc->images[i].sampler);
@@ -332,7 +333,8 @@ comp_swapchain_create(struct xrt_compositor *xc,
 
 	vk_submit_cmd_buffer(&c->vk, cmd_buffer);
 
-	return &sc->base.base;
+	*out_xsc = &sc->base.base;
+	return XRT_SUCCESS;
 }
 
 static void

src/xrt/include/xrt/xrt_compositor.h

@@ -425,8 +425,9 @@ struct xrt_compositor
 	/*!
 	 * Create a swapchain with a set of images.
 	 */
-	struct xrt_swapchain *(*create_swapchain)(
+	xrt_result_t (*create_swapchain)(struct xrt_compositor *xc,
-	    struct xrt_compositor *xc, struct xrt_swapchain_create_info *info);
+	                                 struct xrt_swapchain_create_info *info,
+	                                 struct xrt_swapchain **out_xsc);
 
 	/*!
 	 * Poll events from this compositor.
@@ -548,11 +549,12 @@ struct xrt_compositor
  *
  * @public @memberof xrt_compositor
  */
-static inline struct xrt_swapchain *
+static inline xrt_result_t
 xrt_comp_create_swapchain(struct xrt_compositor *xc,
-                          struct xrt_swapchain_create_info *info)
+                          struct xrt_swapchain_create_info *info,
+                          struct xrt_swapchain **out_xsc)
 {
-	return xc->create_swapchain(xc, info);
+	return xc->create_swapchain(xc, info, out_xsc);
 }
 
 /*!
@@ -916,12 +918,17 @@ struct xrt_compositor_native
  *
  * @public @memberof xrt_compositor_native
  */
-static inline struct xrt_swapchain_native *
+static inline xrt_result_t
 xrt_comp_native_create_swapchain(struct xrt_compositor_native *xcn,
-                                 struct xrt_swapchain_create_info *info)
+                                 struct xrt_swapchain_create_info *info,
+                                 struct xrt_swapchain_native **out_xscn)
 {
-	struct xrt_swapchain *xsc = xrt_comp_create_swapchain(&xcn->base, info);
+	struct xrt_swapchain *xsc = NULL;
-	return (struct xrt_swapchain_native *)xsc;
+	xrt_result_t ret = xrt_comp_create_swapchain(&xcn->base, info, &xsc);
+	if (ret == XRT_SUCCESS) {
+		*out_xscn = (struct xrt_swapchain_native *)xsc;
+	}
+	return ret;
 }
 
 /*!

src/xrt/include/xrt/xrt_results.h

@@ -14,5 +14,7 @@ typedef enum xrt_result
 	XRT_SUCCESS = 0,
 	XRT_ERROR_IPC_FAILURE = -1,
 	XRT_ERROR_NO_IMAGE_AVAILABLE = -2,
-	XRT_ERROR_FAILED_TO_SUBMIT_VULKAN_COMMANDS = -3,
+	XRT_ERROR_VULKAN = -3,
+	XRT_ERROR_OPENGL = -4,
+	XRT_ERROR_FAILED_TO_SUBMIT_VULKAN_COMMANDS = -5,
 } xrt_result_t;

src/xrt/ipc/ipc_client_compositor.c

@@ -164,9 +164,10 @@ ipc_compositor_swapchain_release_image(struct xrt_swapchain *xsc,
  *
  */
 
-static struct xrt_swapchain *
+static xrt_result_t
 ipc_compositor_swapchain_create(struct xrt_compositor *xc,
-                                struct xrt_swapchain_create_info *info)
+                                struct xrt_swapchain_create_info *info,
+                                struct xrt_swapchain **out_xsc)
 {
 	struct ipc_client_compositor *icc = ipc_client_compositor(xc);
 
@@ -184,7 +185,7 @@ ipc_compositor_swapchain_create(struct xrt_compositor *xc,
 	                              remote_fds,             // fds
 	                              IPC_MAX_SWAPCHAIN_FDS); // fds
 	if (r != XRT_SUCCESS) {
-		return NULL;
+		return r;
 	}
 
 	struct ipc_client_swapchain *ics =
@@ -202,7 +203,8 @@ ipc_compositor_swapchain_create(struct xrt_compositor *xc,
 		ics->base.images[i].size = size;
 	}
 
-	return &ics->base.base;
+	*out_xsc = &ics->base.base;
+	return XRT_SUCCESS;
 }
 
 static xrt_result_t

src/xrt/ipc/ipc_server_client.c

@@ -280,6 +280,8 @@ ipc_handle_swapchain_create(volatile struct ipc_client_state *ics,
                             xrt_graphics_buffer_handle_t *out_handles,
                             uint32_t *out_num_handles)
 {
+	xrt_result_t xret = XRT_SUCCESS;
+
 	// Our handle is just the index for now.
 	uint32_t index = 0;
 	for (; index < IPC_MAX_CLIENT_SWAPCHAINS; index++) {
@@ -293,12 +295,16 @@ ipc_handle_swapchain_create(volatile struct ipc_client_state *ics,
 		return XRT_ERROR_IPC_FAILURE;
 	}
 
+	// create the swapchain
+	struct xrt_swapchain *xsc = NULL;
+	xret = xrt_comp_create_swapchain(ics->xc, info, &xsc);
+	if (xret != XRT_SUCCESS) {
+		return xret;
+	}
+
 	// It's now safe to increment the number of swapchains.
 	ics->num_swapchains++;
 
-	// create the swapchain
-	struct xrt_swapchain *xsc = xrt_comp_create_swapchain(ics->xc, info);
-
 	uint32_t num_images = xsc->num_images;
 
 	IPC_SPEW(ics->server, "IPC: Created swapchain %d\n", index);

src/xrt/state_trackers/oxr/oxr_swapchain.c

@@ -198,6 +198,8 @@ oxr_create_swapchain(struct oxr_logger *log,
                      const XrSwapchainCreateInfo *createInfo,
                      struct oxr_swapchain **out_swapchain)
 {
+	xrt_result_t xret = XRT_SUCCESS;
+
 	struct xrt_swapchain_create_info info;
 	info.create = convert_create_flags(createInfo->createFlags);
 	info.bits = convert_usage_bits(createInfo->usageFlags);
@@ -209,13 +211,13 @@ oxr_create_swapchain(struct oxr_logger *log,
 	info.array_size = createInfo->arraySize;
 	info.mip_count = createInfo->mipCount;
 
-	struct xrt_swapchain *xsc =
+	struct xrt_swapchain *xsc = NULL;
-	    xrt_comp_create_swapchain(sess->compositor, &info);
+	xret = xrt_comp_create_swapchain(sess->compositor, &info, &xsc);
-
+	if (xret != XRT_SUCCESS) {
-	if (xsc == NULL) {
 		return oxr_error(log, XR_ERROR_RUNTIME_FAILURE,
 		                 "Failed to create swapchain");
 	}
+	assert(xsc != NULL);
 
 	struct oxr_swapchain *sc = NULL;
 	OXR_ALLOCATE_HANDLE_OR_RETURN(log, sc, OXR_XR_DEBUG_SWAPCHAIN,