buffer: add format param to get_data_ptr

Allow wlr_buffer_impl.get_data_ptr to return a format.

This allows the Pixman renderer to not care about get_dmabuf/get_shm,
and only care about get_data_ptr. This will also help with [1], because
client wl_shm buffers can't implement get_shm.

[1]: https://github.com/swaywm/wlroots/pull/2892

References: https://github.com/swaywm/wlroots/issues/2864

2 files changed, 6 insertions, 15 deletions

diff --git a/render/pixman/renderer.c b/render/pixman/renderer.c
index 3aa32f15..e50b774f 100644
--- a/render/pixman/renderer.c
+++ b/render/pixman/renderer.c
@@ -83,26 +83,16 @@ static struct wlr_pixman_buffer *create_buffer(
 	buffer->buffer = wlr_buffer;
 	buffer->renderer = renderer;
 
-	uint32_t drm_format;
-	struct wlr_dmabuf_attributes dmabuf = {0};
-	struct wlr_shm_attributes shm = {0};
-	if (wlr_buffer_get_dmabuf(wlr_buffer, &dmabuf)) {
-		drm_format = dmabuf.format;
-	} else if (wlr_buffer_get_shm(wlr_buffer, &shm)) {
-		drm_format = shm.format;
-	} else {
-		goto error_buffer;
-	}
-
-	uint32_t format = get_pixman_format_from_drm(drm_format);
-
 	void *data = NULL;
+	uint32_t drm_format;
 	size_t stride;
-	if (!buffer_get_data_ptr(wlr_buffer, &data, &stride)) {
+	if (!buffer_get_data_ptr(wlr_buffer, &data, &drm_format, &stride)) {
 		wlr_log(WLR_ERROR, "Failed to get buffer data");
 		goto error_buffer;
 	}
 
+	uint32_t format = get_pixman_format_from_drm(drm_format);
+
 	buffer->image = pixman_image_create_bits(format, wlr_buffer->width,
 			wlr_buffer->height, data, stride);
 	if (!buffer->image) {
diff --git a/render/shm_allocator.c b/render/shm_allocator.c
index 3bfb62e5..8da7bea6 100644
--- a/render/shm_allocator.c
+++ b/render/shm_allocator.c
@@ -31,9 +31,10 @@ static bool buffer_get_shm(struct wlr_buffer *wlr_buffer,
 }
 
 static bool buffer_get_data_ptr(struct wlr_buffer *wlr_buffer, void **data,
-		size_t *stride) {
+		uint32_t *format, size_t *stride) {
 	struct wlr_shm_buffer *buffer = shm_buffer_from_buffer(wlr_buffer);
 	*data = buffer->data;
+	*format = buffer->shm.format;
 	*stride = buffer->shm.stride;
 	return true;
 }