buffer: re-use wlr_shm_client_buffer

The first time wlr_buffer_from_resource is called with a wl_buffer
resource that originates from wl_shm, create a new
wlr_shm_client_buffer as usual. If wlr_buffer_from_resource is called
multiple times, re-use the existing wlr_shm_client_buffer.

This commit changes how the wlr_shm_client_buffer lifetime is managed:
previously it was destroyed as soon as the wlr_buffer was released.
With this commit it's destroyed when the wl_buffer resource is.

Apart from de-duplicating wlr_shm_client_buffer creations, this allows
to easily track when a wlr_shm_client_buffer is re-used. This is useful
for the renderer and the backends, e.g. the Pixman renderer can keep
using the same Pixman image if the buffer is re-used. In the future,
this will also allow to re-use resources in the Wayland and X11 backends
(remote wl_buffer objects for Wayland, pixmaps for X11).
This commit is contained in:
Simon Ser 2021-07-19 19:04:38 +02:00 committed by Simon Zeni
parent f94eb174c7
commit 8afb4d8bf0
2 changed files with 16 additions and 8 deletions

View file

@ -22,9 +22,6 @@ struct wlr_shm_client_buffer {
struct wl_listener release;
};
struct wlr_shm_client_buffer *shm_client_buffer_create(
struct wl_resource *resource);
/**
* A read-only buffer that holds a data pointer.
*

View file

@ -153,6 +153,8 @@ static void client_buffer_handle_source_destroy(struct wl_listener *listener,
client_buffer->source = NULL;
}
static struct wlr_shm_client_buffer *shm_client_buffer_get_or_create(
struct wl_resource *resource);
static bool buffer_is_shm_client_buffer(struct wlr_buffer *buffer);
static struct wlr_shm_client_buffer *shm_client_buffer_from_buffer(
struct wlr_buffer *buffer);
@ -164,15 +166,12 @@ struct wlr_buffer *wlr_buffer_from_resource(struct wlr_renderer *renderer,
struct wlr_buffer *buffer;
if (wl_shm_buffer_get(resource) != NULL) {
struct wlr_shm_client_buffer *shm_client_buffer =
shm_client_buffer_create(resource);
shm_client_buffer_get_or_create(resource);
if (shm_client_buffer == NULL) {
wlr_log(WLR_ERROR, "Failed to create shm client buffer");
return NULL;
}
// Ensure the buffer will be released before being destroyed
buffer = wlr_buffer_lock(&shm_client_buffer->base);
wlr_buffer_drop(&shm_client_buffer->base);
} else if (wlr_dmabuf_v1_resource_is_buffer(resource)) {
struct wlr_dmabuf_v1_buffer *dmabuf =
wlr_dmabuf_v1_buffer_from_buffer_resource(resource);
@ -347,6 +346,9 @@ static void shm_client_buffer_resource_handle_destroy(
buffer->shm_buffer = NULL;
wl_list_remove(&buffer->resource_destroy.link);
wl_list_init(&buffer->resource_destroy.link);
// This might destroy the buffer
wlr_buffer_drop(&buffer->base);
}
static void shm_client_buffer_handle_release(struct wl_listener *listener,
@ -358,11 +360,20 @@ static void shm_client_buffer_handle_release(struct wl_listener *listener,
}
}
struct wlr_shm_client_buffer *shm_client_buffer_create(
static struct wlr_shm_client_buffer *shm_client_buffer_get_or_create(
struct wl_resource *resource) {
struct wl_shm_buffer *shm_buffer = wl_shm_buffer_get(resource);
assert(shm_buffer != NULL);
struct wl_listener *resource_destroy_listener =
wl_resource_get_destroy_listener(resource,
shm_client_buffer_resource_handle_destroy);
if (resource_destroy_listener != NULL) {
struct wlr_shm_client_buffer *buffer =
wl_container_of(resource_destroy_listener, buffer, resource_destroy);
return buffer;
}
int32_t width = wl_shm_buffer_get_width(shm_buffer);
int32_t height = wl_shm_buffer_get_height(shm_buffer);