[PATCH 3/3] wayland-cursor: Adapt to new shm pool helper functions

[Ander Conselvan de Oliveira]

On 08/04/2012 04:22 PM, Andre Heider wrote:
> ---
>   cursor/wayland-cursor.c |  115 ++++++++++-------------------------------------
>   1 file changed, 24 insertions(+), 91 deletions(-)
>
> diff --git a/cursor/wayland-cursor.c b/cursor/wayland-cursor.c
> index 10e8f62..8e467f6 100644
> --- a/cursor/wayland-cursor.c
> +++ b/cursor/wayland-cursor.c

[...]

> @@ -220,9 +142,21 @@ wl_cursor_create_from_xcursor_images(XcursorImages *images,
>
>   		/* copy pixels to shm pool */
>   		size = image->image.width * image->image.height * 4;
> -		image->offset = shm_pool_allocate(theme->pool, size);
> -		memcpy(theme->pool->data + image->offset,
> -		       images->images[i]->pixels, size);
> +		p = wl_shm_pool_helper_allocate(theme->pool, size, &offset);
> +		if (!p) {
> +			resize = 2 * wl_shm_pool_helper_get_size(theme->pool) +
> +				 size;
> +			if (!wl_shm_pool_helper_resize(theme->pool, resize)) {
> +				free(cursor);
> +				return NULL;
> +			}

I like to have the allocate function try to resize the pool if needed. 
All users except wayland-cursor allocate a pool large enough, so they 
should never reach and on the other hand its convenient not to have to 
write the resize logic every time one needs it.

I would go for having the resize by default, and if there is a use case 
where we really don't want to resize, we could have something like:

enum wl_shm_mapping_resize_behavior {
	/* never try to resize */
	WL_SHM_MAPPING_RESIZE_NEVER,

	/* try to resize to current size + new allocation size */
	WL_SHM_MAPPING_RESIZE_ADD_SIZE,

	/* double the allocation size until it is large enough */
	WL_SHM_MAPPING_RESIZE_DOUBLE,

	...
};

void
wl_shm_mapping_set_resize_behavior(struct wl_shm_mapping *mapping,
				   enum wl_shm_mapping_resize_behavior behavior);

Or maybe have that as flags for wl_shm_mapping_create(). But the former 
is a change that can be done in the future without breaking the API.


Ander


> +
> +			p = wl_shm_pool_helper_allocate(theme->pool, size,
> +							&offset);
> +		}
> +
> +		image->offset = offset;
> +		memcpy(p, images->images[i]->pixels, size);
>   	}
>
>   	return &cursor->cursor;
> @@ -280,8 +214,7 @@ wl_cursor_theme_load(const char *name, int size, struct wl_shm *shm)
>   	theme->cursor_count = 0;
>   	theme->cursors = NULL;
>
> -	theme->pool =
> -		shm_pool_create(shm, size * size * 4);
> +	theme->pool = wl_shm_pool_helper_create(shm, size * size * 4);
>   	if (!theme->pool) {
>   		free(theme->name);
>   		free(theme);
> @@ -305,7 +238,7 @@ wl_cursor_theme_destroy(struct wl_cursor_theme *theme)
>   	for (i = 0; i < theme->cursor_count; i++)
>   		wl_cursor_destroy(theme->cursors[i]);
>
> -	shm_pool_destroy(theme->pool);
> +	wl_shm_pool_helper_destroy(theme->pool, 1);
>
>   	free(theme->cursors);
>   	free(theme);
>