volume.c

创建一个符合iso-9660标准的iso文件系统

/* @(#)volume.c	1.6 00/04/27 joerg, Copyright 1997, 1998, 1999, 2000 James Pearson */
#ifndef lint
static	char sccsid[] =
	"@(#)volume.c	1.6 00/04/27 joerg, Copyright 1997, 1998, 1999, 2000 James Pearson";
#endif
/*
 *      Copyright (c) 1997, 1998, 1999, 2000 James Pearson
 *
 * 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, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *	volume.c: prepare HFS volume for mkhybrid
 *
 *	James Pearson 17/7/97
 *	modified JCP 29/7/97 to improve allocation sizes to cut
 *	down on wasted space. Now uses the HFS "allocation" size rounded
 *	up to the nearest 2048 bytes. Savings can be significant with
 *	a large volume containing lots of smallish files.
 *
 *	Updated for v1.12 - now uses the built in RELOCATED_DIRECTORY
 *	flag for finding the real directory location JCP 8/1/97
 */

#ifdef APPLE_HYB

#include "config.h"
#include "mkisofs.h"
#include <errno.h>

#define HFS_MIN_SIZE	1600	/* 800k == 1600 HFS blocks */

static hfsvol  *vol_save = 0;	/* used to "destroy" an HFS volume */

static int	AlcSiz		__PR((int));
static int	XClpSiz		__PR((int));
static int	get_vol_size	__PR((int));
	int	make_mac_volume	__PR((struct directory *, int));
static int	copy_to_mac_vol	__PR((hfsvol *, struct directory *));
static void	set_dir_info	__PR((hfsvol *, struct directory *));

/*
 *	AlcSiz: find allocation size for given volume size
 */
static int
AlcSiz(vlen)
	int	vlen;
{
	int	lpa,
		drAlBlkSiz;

	/* code extracted from hfs_format() */
	lpa = 1 + vlen / 65536;
	drAlBlkSiz = lpa * HFS_BLOCKSZ;

	/*
	 * now set our "allocation size" to the allocation block rounded up to
	 * the nearest SECTOR_SIZE (2048 bytes)
	 */
	drAlBlkSiz = ROUND_UP(drAlBlkSiz, SECTOR_SIZE);

	return (drAlBlkSiz);
}

/*
 *	XClpSiz: find the default size of the catalog/extent file
 */
static int
XClpSiz(vlen)
	int	vlen;
{
	int	olpa,
		lpa,
		drNmAlBlks,
		drAlBlkSiz;
	int	vbmsz,
		drXTClpSiz;

	/* code extracted from hfs_format() */

	/* get the lpa from our calculated allocation block size */
	drAlBlkSiz = AlcSiz(vlen);
	lpa = drAlBlkSiz / HFS_BLOCKSZ;

	vbmsz = (vlen / lpa + 4095) / 4096;
	drNmAlBlks = (vlen - 5 - vbmsz) / lpa;
	drXTClpSiz = drNmAlBlks / 128 * drAlBlkSiz;

	/*
	 * make allowances because we have possibly rounded up the
	 * allocation size get the "original" lpa "
	 */
	olpa = 1 + vlen / 65536;

	/* adjust size upwards */
	drXTClpSiz = (drXTClpSiz * lpa) / olpa;

	/* round up to the nearest alloaction size */
	drXTClpSiz = ROUND_UP(drXTClpSiz, drAlBlkSiz);

	return (drXTClpSiz);
}

/*
 *	get_vol_size: get the size of the volume including the extent/catalog
 */
static int
get_vol_size(vblen)
	int	vblen;
{
	int	drXTClpSiz;
	int	drAlBlkSiz;
	int	new_vblen;

	/*
	 * try to estimate a "volume size" based on the code in hfs_format
	 * - we need the size of the catalog/extents and Desktop files included
	 * in the volume, as we add this to the end of the ISO volume
	 */
	drXTClpSiz = XClpSiz(vblen);
	drAlBlkSiz = AlcSiz(vblen);

	/*
	 * catalog file is set at CTC times (default twice) the extents
	 * file size - hence the (ctc_size + 1) below. The Desktop starts of
	 * the same size as the "clump size" == 4 x drAlBlkSiz,
	 * plus a spare drAlBlkSiz for the alternative MDB
	 */
	new_vblen = vblen +
	    ((hce->ctc_size + 1) * drXTClpSiz + 5 * drAlBlkSiz) / HFS_BLOCKSZ;

	return (new_vblen);
}

/*
 *	write_fork: "write" file data to the volume
 *
 *	This is used to update the HFS file internal structures
 *	but no data is actually written (it's trapped deep down in
 *	libhfs).
 */
int
write_fork(hfp, tot)
	hfsfile	*hfp;
	long	tot;
{
	char		blk[HFS_BLOCKSZ];
	unsigned short	start;
	long		len;

	len = tot;
	/* we need to know where this fork starts */
	start = hfs_get_drAllocPtr(hfp);

	/* loop through the data a block at a time */
	while (len >= HFS_BLOCKSZ) {
		if (hfs_write(hfp, blk, HFS_BLOCKSZ) < 0)
			return (-1);
		len -= HFS_BLOCKSZ;
	}
	/* write out anything left */
	if (len)
		if (hfs_write(hfp, blk, len) < 0)
			return (-1);

	/*
	 * set the start of the allocation search to be immediately after
	 * this fork
	 */
	hfs_set_drAllocPtr(hfp, start, tot);

	return (0);
}

/*
 *	make_mac_volume: "create" an HFS volume using the ISO data
 *
 *	The HFS volume structures are set up (but no data is written yet).
 *
 *	ISO volumes have a allocation size of 2048 bytes - regardless
 *	of the size of the volume. HFS allocation size is depends on volume
 *	size, so we may have to update the ISO structures to add in any
 *	padding.
 */
int
make_mac_volume(dpnt, start_extent)
	struct directory	*dpnt;
	int			start_extent;
{
	char	vol_name[HFS_MAX_VLEN + 1];	/* Mac volume name */
	hfsvol	*vol;			/* Mac volume */
	int	vlen,
		vblen;			/* vol length (bytes, blocks) */
	int	Csize,
		lastCsize;		/* allocation sizes */
	int	ret = 0;		/* return value */
	int	loop = 1;

	/* umount volume if we have had a previous attempt */
	if (vol_save)
		if (hfs_umount(vol_save, 0) < 0)
			return (-1);

	/* set the default clump size to the ISO block size */
	Csize = lastCsize = SECTOR_SIZE;

	if (verbose > 1)
		fprintf(stderr, "Creating HFS Volume info\n");

	/* name or copy ISO volume name to Mac Volume name */
	strncpy(vol_name, hfs_volume_id ? hfs_volume_id : volume_id,
								HFS_MAX_VLEN);
	vol_name[HFS_MAX_VLEN] = '\0';

	/* get initial size of HFS volume (size of current ISO volume) */
	vblen = (last_extent - session_start) * HFS_BLK_CONV;

	/* make sure volume is at least 800k */
	if (vblen < HFS_MIN_SIZE)
		vblen += insert_padding_file(HFS_MIN_SIZE - vblen);

	/*
	 * add on size of extents/catalog file, but this may mean the
	 * allocation size will change, so loop round until the
	 * allocation size doesn't change
	 */
	while (loop) {
		hce->XTCsize = XClpSiz(vblen);
		vblen = get_vol_size(vblen);
		Csize = AlcSiz(vblen);

		if (Csize == lastCsize) {
			/* allocation size hasn't changed, so carry on */
			loop = 0;
		} else {
			/*
			 * allocation size has changed, so update
			 * ISO volume size
			 */
			if ((vlen = get_adj_size(Csize)) < 0) {
				sprintf(hce->error,
					"too many files for HFS volume");
				return (-1);
			}
			vlen +=
			  ROUND_UP((start_extent - session_start) * SECTOR_SIZE,
								Csize);
			vblen = vlen / HFS_BLOCKSZ;
			lastCsize = Csize;
		}
	}

	/* set vlen to size in bytes */
	/* take off the label/map size */
	vblen -= hce->hfs_map_size;

	vlen = hce->hfs_vol_size = vblen * HFS_BLOCKSZ;

	/* set the default allocation size for libhfs */
	hce->Csize = Csize;

	/* format and mount the "volume" */
	if (hfs_format(hce, 0, vol_name) < 0) {
		sprintf(hce->error, "can't HFS format %s", vol_name);
		return (-1);
	}
	/*
	 * update the ISO structures with new start extents and any
	 * padding required
	 */
	if (Csize != SECTOR_SIZE) {
		last_extent = adj_size(Csize, start_extent,
					hce->hfs_hdr_size + hce->hfs_map_size);
		adj_size_other(dpnt);
	}
	if ((vol = hfs_mount(hce, 0, 0)) == 0) {
		sprintf(hce->error, "can't HFS mount %s", vol_name);
		return (-1);
	}
	/* save the volume for possible later use */
	vol_save = vol;

	/*
	 * Recursively "copy" the files to the volume
	 * - we need to know the first allocation block in the volume as
	 * starting blocks of files are relative to this.
	 */
	ret = copy_to_mac_vol(vol, dpnt);
	if (ret < 0)
		return (ret);

	/*
	 * make the Desktop files - I *think* this stops the Mac rebuilding the
	 * desktop when the CD is mounted on a Mac These will be ignored if they
	 * already exist
	 */
	if (create_dt)
		ret = make_desktop(vol,
				(last_extent - session_start) * HFS_BLK_CONV);
	if (ret < 0)
		return (ret);

	/* close the volume */
	if (hfs_flush(vol) < 0)
		return (-1);

	/* unmount and set the start blocks for the catalog/extents files */
	if (hfs_umount(vol, (last_extent - session_start) * HFS_BLK_CONV) < 0)
		return (-1);

	return (Csize);
}

#define TEN 10	/* well, it is! */
#define LCHAR "_"

/*	copy_to_mac_vol: copy all files in a directory to corresponding
 *			 Mac folder.
 *
 *	Files are copied recursively to corresponding folders on the Mac
 *	volume. The caller routine needs to do a hfs_chdir before calling this
 *	routine.
 */
static int
copy_to_mac_vol(vol, node)
	hfsvol		*vol;
	struct directory *node;
{
	struct directory_entry	*s_entry;	/* ISO directory entry */
	struct directory_entry	*s_entry1;	/* tmp ISO directory entry */
	struct directory	*dpnt;		/* ISO directory */

	hfsfile			*hfp;		/* HFS file */
	hfsdirent		*ent;		/* HFS file entities */
	long			id;		/* current HFS folder */
	long			dext,
				rext;		/* real data/rsrc start blk */
	int			ret;		/* result code */
	int			new_name;	/* HFS file has modified name */

	int			tens;
	int			digits;
	int			i;