text: /*	$NetBSD: bt_conv.c,v 1.10.2.1 2004/06/22 07:16:34 tron Exp $	*/
  
  /*-
   * Copyright (c) 1990, 1993, 1994
   *	The Regents of the University of California.  All rights reserved.
   *
   * This code is derived from software contributed to Berkeley by
   * Mike Olson.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  #if HAVE_NBTOOL_CONFIG_H
  #include "nbtool_config.h"
  #endif
  
  #include <sys/cdefs.h>
  #if defined(LIBC_SCCS) && !defined(lint)
  #if 0
  static char sccsid[] = "@(#)bt_conv.c	8.5 (Berkeley) 8/17/94";
  #else
  __RCSID("$NetBSD: bt_conv.c,v 1.10.2.1 2004/06/22 07:16:34 tron Exp $");
  #endif
  #endif /* LIBC_SCCS and not lint */
  
  #include <stdio.h>
  
  #include <db.h>
  #include "btree.h"
  
  static void mswap __P((PAGE *));
  
  /*
   * __BT_BPGIN, __BT_BPGOUT --
   *	Convert host-specific number layout to/from the host-independent
   *	format stored on disk.
   *
   * Parameters:
   *	t:	tree
   *	pg:	page number
   *	h:	page to convert
   */
  void
  __bt_pgin(t, pg, pp)
  	void *t;
  	pgno_t pg;
  	void *pp;
  {
  	PAGE *h;
  	indx_t i, top;
  	u_char flags;
  	char *p;
  
  	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
  		return;
  	if (pg == P_META) {
  		mswap(pp);
  		return;
  	}
  
  	h = pp;
  	M_32_SWAP(h->pgno);
  	M_32_SWAP(h->prevpg);
  	M_32_SWAP(h->nextpg);
  	M_32_SWAP(h->flags);
  	M_16_SWAP(h->lower);
  	M_16_SWAP(h->upper);
  
  	top = NEXTINDEX(h);
  	if ((h->flags & P_TYPE) == P_BINTERNAL)
  		for (i = 0; i < top; i++) {
  			M_16_SWAP(h->linp[i]);
  			p = (char *)(void *)GETBINTERNAL(h, i);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			P_32_SWAP(p);
  			p += sizeof(pgno_t);
  			if (*(u_char *)p & P_BIGKEY) {
  				p += sizeof(u_char);
  				P_32_SWAP(p);
  				p += sizeof(pgno_t);
  				P_32_SWAP(p);
  			}
  		}
  	else if ((h->flags & P_TYPE) == P_BLEAF)
  		for (i = 0; i < top; i++) {
  			M_16_SWAP(h->linp[i]);
  			p = (char *)(void *)GETBLEAF(h, i);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			flags = *(u_char *)p;
  			if (flags & (P_BIGKEY | P_BIGDATA)) {
  				p += sizeof(u_char);
  				if (flags & P_BIGKEY) {
  					P_32_SWAP(p);
  					p += sizeof(pgno_t);
  					P_32_SWAP(p);
  				}
  				if (flags & P_BIGDATA) {
  					p += sizeof(u_int32_t);
  					P_32_SWAP(p);
  					p += sizeof(pgno_t);
  					P_32_SWAP(p);
  				}
  			}
  		}
  }
  
  void
  __bt_pgout(t, pg, pp)
  	void *t;
  	pgno_t pg;
  	void *pp;
  {
  	PAGE *h;
  	indx_t i, top;
  	u_char flags;
  	char *p;
  
  	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
  		return;
  	if (pg == P_META) {
  		mswap(pp);
  		return;
  	}
  
  	h = pp;
  	top = NEXTINDEX(h);
  	if ((h->flags & P_TYPE) == P_BINTERNAL)
  		for (i = 0; i < top; i++) {
  			p = (char *)(void *)GETBINTERNAL(h, i);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			P_32_SWAP(p);
  			p += sizeof(pgno_t);
  			if (*(u_char *)p & P_BIGKEY) {
  				p += sizeof(u_char);
  				P_32_SWAP(p);
  				p += sizeof(pgno_t);
  				P_32_SWAP(p);
  			}
  			M_16_SWAP(h->linp[i]);
  		}
  	else if ((h->flags & P_TYPE) == P_BLEAF)
  		for (i = 0; i < top; i++) {
  			p = (char *)(void *)GETBLEAF(h, i);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			P_32_SWAP(p);
  			p += sizeof(u_int32_t);
  			flags = *(u_char *)p;
  			if (flags & (P_BIGKEY | P_BIGDATA)) {
  				p += sizeof(u_char);
  				if (flags & P_BIGKEY) {
  					P_32_SWAP(p);
  					p += sizeof(pgno_t);
  					P_32_SWAP(p);
  				}
  				if (flags & P_BIGDATA) {
  					p += sizeof(u_int32_t);
  					P_32_SWAP(p);
  					p += sizeof(pgno_t);
  					P_32_SWAP(p);
  				}
  			}
  			M_16_SWAP(h->linp[i]);
  		}
  
  	M_32_SWAP(h->pgno);
  	M_32_SWAP(h->prevpg);
  	M_32_SWAP(h->nextpg);
  	M_32_SWAP(h->flags);
  	M_16_SWAP(h->lower);
  	M_16_SWAP(h->upper);
  }
  
  /*
   * MSWAP -- Actually swap the bytes on the meta page.
   *
   * Parameters:
   *	p:	page to convert
   */
  static void
  mswap(pg)
  	PAGE *pg;
  {
  	char *p;
  
  	p = (char *)(void *)pg;
  	P_32_SWAP(p);		/* magic */
  	p += sizeof(u_int32_t);
  	P_32_SWAP(p);		/* version */
  	p += sizeof(u_int32_t);
  	P_32_SWAP(p);		/* psize */
  	p += sizeof(u_int32_t);
  	P_32_SWAP(p);		/* free */
  	p += sizeof(u_int32_t);
  	P_32_SWAP(p);		/* nrecs */
  	p += sizeof(u_int32_t);
  	P_32_SWAP(p);		/* flags */
  	p += sizeof(u_int32_t);
  }
  