labwc/include/common/array.h

44 lines
1.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef LABWC_ARRAY_H
#define LABWC_ARRAY_H
#include <wayland-server-core.h>
/*
* Wayland's wl_array API is a bit sparse consisting only of
* - init
* - release
* - add
* - copy
* - for_each
*
* The purpose of this header is the gather any generic wl_array helpers we
* create.
*
* We take the liberty of using the wl_ suffix here to make it look a bit
* prettier. If Wayland extend the API in future, we will sort the clash then.
*/
/**
* wl_array_len() - return length of wl_array
* @array: wl_array for which to calculate length
* Note: The pointer type might not be 'char' but this is the approach that
* wl_array_for_each() takes, so we align with their style.
*/
static inline size_t
wl_array_len(struct wl_array *array)
{
return array->size / sizeof(const char *);
}
/**
* Iterates in reverse over an array.
* @pos: pointer that each array element will be assigned to
* @array: wl_array to iterate over
*/
#define wl_array_for_each_reverse(pos, array) \
for (pos = !(array)->data ? NULL \
: (void *)((const char *)(array)->data + (array)->size - sizeof(pos)); \
pos && (const char *)pos >= (const char *)(array)->data; \
(pos)--)
#endif /* LABWC_ARRAY_H */