/**
* Rezerwuje ciągły obszar w danym segmencie.
* @param vseg deskryptor segmentu.
* @param size rozmiar ciągłego obszaru.
* @param _res adres zmiennej, do uzupełnienia przydzielonym adresem.
*/
int
vm_seg_reserve(vm_seg_t *vseg, vm_size_t size, void *_res)
{
int expand = EXPAND_UP;
vm_addr_t *res = _res;
size = PAGE_ROUND(size);
vm_region_t *region = list_head(&vseg->regions);
if (region == NULL) {
if (do_first_region(vseg, ®ion)) return -1;
}
// sprawdzamy czy istnieje dziura pomiędzy początkiem segmentu
// a pierwszym regionem
if (size < region->begin - vseg->base) {
*res = region->begin - size;
return expand_region(vseg, region, size, EXPAND_DOWN, _res);
}
// Ok, no to szukamy dziury za regionem
region = list_find(&vseg->regions, has_hole_after_reg, size);
if (region == NULL) {
if (vseg->flags & VM_SEG_EXPDOWN) {
expand = EXPAND_DOWN;
region = list_head(&vseg->regions);
*res = region->begin - size;
} else {
region = list_tail(&vseg->regions);
*res = region->end;
}
} else {
*res = region->end;
}
return expand_region(vseg, region, size, expand, _res);
}
/**
* meta_make_border_region:
* @region: a #cairo_region_t
* @x_amount: distance from the border to extend horizontally
* @y_amount: distance from the border to extend vertically
* @flip: if true, the result is computed with x and y interchanged
*
* Computes the "border region" of a given region, which is roughly
* speaking the set of points near the boundary of the region. If we
* define the operation of growing a region as computing the set of
* points within a given manhattan distance of the region, then the
* border is 'grow(region) intersect grow(inverse(region))'.
*
* If we create an image by filling the region with a solid color,
* the border is the region affected by blurring the region.
*
* Return value: a new region which is the border of the given region
*/
cairo_region_t *
meta_make_border_region (cairo_region_t *region,
int x_amount,
int y_amount,
gboolean flip)
{
cairo_region_t *border_region;
cairo_region_t *inverse_region;
border_region = expand_region (region, x_amount, y_amount, flip);
inverse_region = expand_region_inverse (region, x_amount, y_amount, flip);
cairo_region_intersect (border_region, inverse_region);
cairo_region_destroy (inverse_region);
return border_region;
}
