jehanne/sys/src/lib/memdraw/unload.c

35 lines
862 B
C

/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <libc.h>
#include <draw.h>
#include <memdraw.h>
int
unloadmemimage(Memimage *i, Rectangle r, uint8_t *data, int ndata)
{
int y, l;
uint8_t *q;
if(!rectinrect(r, i->r))
return -1;
l = bytesperline(r, i->depth);
if(ndata < l*Dy(r))
return -1;
ndata = l*Dy(r);
q = byteaddr(i, r.min);
for(y=r.min.y; y<r.max.y; y++){
jehanne_memmove(data, q, l);
q += i->width*sizeof(uint32_t);
data += l;
}
return ndata;
}