/* vi:set tabstop=2 cindent shiftwidth=2: */
/*
 * libvxfs - library for reading Veritas Journaled FileSystem (VxFS)
 * Copyright (c) 1999 Martin Hinner <mhi@penguin.cz>
 *
 * bmap.c: Maps extents to blocks
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id$
 */
#include <stdio.h>
#include <stdlib.h>

#include <libvxfs.h>

int
vxbmap_ext4 (struct vxfs_inode *ino, int block)
{
	int i;
	int size;
	int blk;
	__u32 *ind;

	if (ino->orgtype != VXFS_ORG_EXT4)
		{
			if (vxverbose)
				fprintf (stderr, "vxbmap_ext4: Organisation type is not EXT4 !\n");
			return -1;
		}
	/*
	 * Try direct blocks 
	 */
	size = 0;
	for (i = 0; i < VXFS_NDADDR; i++)
		{
			if (block >= size && block < (size + ino->org.ext4.direct[i].size))
				return (block - size) + ino->org.ext4.direct[i].extent;
			size += ino->org.ext4.direct[i].size;
		}

	/*
	 * Try indirect blocks 
	 */
	block -= size;
	if (block / (ino->org.ext4.indsize * (ino->org.ext4.indsize * (vxbsize / 4))) == 0)
		{
			ind = (__u32 *) vxread (ino->org.ext4.indirect, ino->org.ext4.indsize);
			blk = ind[(block / ino->org.ext4.indsize) % (ino->org.ext4.indsize * vxbsize)] +
				(block % ino->org.ext4.indsize);
			free (ind);
			return blk;
		}
	/*
	 * Try double indirect blocks 
	 */
	if (vxverbose)
		printf ("vxbmap_ext4: Double indirect extents are not supported yet.\n");
	return -1;
}

int
vxbmap_typed (struct vxfs_inode *ino, int block)
{
	int i, blk;
	
	if (ino->orgtype != VXFS_ORG_TYPED)
		{
			if (vxverbose)
				fprintf (stderr, "vxbmap_typed: Organisation type is not TYPED !\n");
			return -1;
		}

	for (i=0;i<VXFS_NTYPED;i++) {
		if (block >= (ino->org.typed[i].hdr & VXFS_TYPED_OFFSETMASK)) {
			switch(ino->org.typed[i].hdr>>VXFS_TYPED_TYPESHIFT) {
				case VXFS_TYPED_INDIRECT:
					blk = vxbmap_typedindir(ino->org.typed[i].block,
							ino->org.typed[i].size,
							block - (ino->org.typed[i].hdr & VXFS_TYPED_OFFSETMASK));
					if (blk != -2)
						return blk;
					break;
				case VXFS_TYPED_DATA:
					if (block - (ino->org.typed[i].hdr & VXFS_TYPED_OFFSETMASK)
							< ino->org.typed[i].size ) 
						return ino->org.typed[i].block + block - 
							(ino->org.typed[i].hdr & VXFS_TYPED_OFFSETMASK);
					break;
			}
		}
	}

	if (vxverbose)
		fprintf(stderr,"vxbmap_typed: Block %u exceeded all typed extents!\n",
				block);
	return -1;
}

/*
 * Return: -1:  Error
 *         -2:  block is not inside this indirect block
 *         >=0: Block number
 */
int vxbmap_typedindir(int indirblock, int size, int block)
{
  int i,j, blk;
	struct vxfs_typed *typed;

	/* printf("vxbmap_typeindir(indirblock=%u, size=%u, block=%u)\n",
			indirblock,size,block); */

	typed = (struct vxfs_typed *) vxread (indirblock,size);

	for (i=0;i<size*(vxbsize/sizeof(struct vxfs_typed));i++) {

#if 0		
		printf("%u: [T%u ",i,typed[i].hdr>>VXFS_TYPED_TYPESHIFT);
		printf("offset=%lx ",typed[i].hdr & VXFS_TYPED_OFFSETMASK);
		printf("block=%x ",typed[i].block);
		printf("size=%x\n",typed[i].size);
#endif
		
		if (block >= (typed[i].hdr & VXFS_TYPED_OFFSETMASK)) {
			switch(typed[i].hdr>>VXFS_TYPED_TYPESHIFT) {
				case VXFS_TYPED_INDIRECT:
					blk = vxbmap_typedindir(typed[i].block,
							typed[i].size,
							block - (typed[i].hdr & VXFS_TYPED_OFFSETMASK));
					if (blk != -2) {
						free(typed);
						return blk;
					}
					break;
				case VXFS_TYPED_DATA:
					if (block - (typed[i].hdr & VXFS_TYPED_OFFSETMASK) < typed[i].size ) {
						blk = typed[i].block + block - (typed[i].hdr & VXFS_TYPED_OFFSETMASK);
						free(typed);
						return blk;
					}
					break;
			}
		}
	}

	free(typed);
  return -1;
}

int
vxbmap_typeddev4 (struct vxfs_inode *ino, int block)
{
	printf("Typed4 (dev) extens are not supported yet\n");
	return -1;
}