#ifndef lint
static	char sccsid[] = "@(#)pr_open.c 9.2 88/01/19 SMI";
#endif

/*
 * Copyright 1986 by Sun Microsystems, Inc.
 *
 * pr_open() function from libpixrect.
 */

/*
 * Pixrect device opening routine.
 */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <sun/fbio.h>
#include <pixrect/pixrect.h>
#include <stdio.h>

/*
 * pixrect create function vector
 * (defined in pr_makefun.c)
 */
extern Pixrect *(*(pr_makefun[FBTYPE_LASTPLUSONE]))();

#define	IS_VALID_FBTYPE(type) \
	((unsigned) (type) < FBTYPE_LASTPLUSONE && pr_makefun[(type)] != 0)

#define	CAN_SATTR(attr) \
	((attr).owner == 0)

Pixrect *
pr_open(fbname)
	char	*fbname;
{
	register int fd;
	register char *errstr;
	struct pr_size fbsize;
	Pixrect *pr;
	struct fbgattr attr;

	if ((fd = open(fbname, O_RDWR, 0)) < 0) {
		errstr = "open failed for";
		goto bad;
	}

	/* force FBIOGTYPE if FBIOGATTR fails */
	attr.fbtype.fb_type = -1;

	/* get frame buffer attributes */
	if (ioctl(fd, FBIOGATTR, &attr) != -1 && CAN_SATTR(attr)) {

		/*
		 * If we can't use the native mode, pick a suitable
		 * emulation mode and turn auto-initialization on.
		 */
		if (!IS_VALID_FBTYPE(attr.fbtype.fb_type)) {
			register int bestemu, *ep;

			fprintf(stderr, "!IS_VALID_FBTYPE %d\n", attr.fbtype.fb_type);

			bestemu = -1;
			for (ep = attr.emu_types; 
				ep < &attr.emu_types[FB_ATTR_NEMUTYPES]; 
				ep++) {
				if (*ep == -1) 
					break;
				if (IS_VALID_FBTYPE(*ep) && *ep > bestemu)
					bestemu = *ep;
			}

			/* skip the ioctl if it wouldn't change anything */
			if (bestemu > 0 
				&& (bestemu != attr.sattr.emu_type ||
				!(attr.sattr.flags & FB_ATTR_AUTOINIT))) {

				attr.sattr.flags |= FB_ATTR_AUTOINIT;
				attr.sattr.emu_type = bestemu;
				(void) ioctl(fd, FBIOSATTR, &attr.sattr);
			}
		}
	}

	/*
	 * If using an emulation mode, get the type information for it.
	 */
	if (!IS_VALID_FBTYPE(attr.fbtype.fb_type) &&
		ioctl(fd, FBIOGTYPE, &attr.fbtype) == -1) {
		errstr = "FBIOGTYPE ioctl failed for";
		goto bad;
	}

	if (!IS_VALID_FBTYPE(attr.fbtype.fb_type)) {
		errstr = "no pixrect implemented for";
		goto bad;
	}

	fbsize.x = attr.fbtype.fb_width;
	fbsize.y = attr.fbtype.fb_height;
	if ((pr = (*pr_makefun[attr.fbtype.fb_type])(fd, fbsize, 
		attr.fbtype.fb_depth)) == 0) {
		errstr = "pixrect create failed for";
		goto bad;
	}
	close(fd);
	return pr;

bad:
	if (fd >= 0)
		close(fd);
	fprintf(stderr, "pr_open: %s %s\n", errstr, fbname);
	return (Pixrect *) 0;
}

#ifdef REF
struct pixrect *
osi_create_screen_device(name_str)
    char *name_str;
{
    register struct pixrect *pr;

    /* Always open a screen pixrect */
    if ((pr = pr_open(name_str)) == 0)
        return (struct pixrect *)0;
    return pr;
}
#endif