multi.c

刻录光盘的程序

/*
 * File multi.c - scan existing iso9660 image and merge into 
 * iso9660 filesystem.  Used for multisession support.
 *
 * Written by Eric Youngdale (1996).
 *
 * 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; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
 */

static char rcsid[] ="$Id: multi.c,v 1.15 1999/11/22 02:36:28 eric Exp $";

#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>

#ifndef VMS

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#else
#include <sys/file.h>
#include <vms/fabdef.h>
#include "vms.h"
extern char * strdup(const char *);
#endif

#include "mkisofs.h"
#include "iso9660.h"

#ifdef	USE_LIBSCHILY
#include <standard.h>
#endif

#ifndef howmany
#define howmany(x, y)   (((x)+((y)-1))/(y))
#endif
#ifndef roundup
#define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))
#endif

#define TF_CREATE 1
#define TF_MODIFY 2
#define TF_ACCESS 4
#define TF_ATTRIBUTES 8

static int  isonum_711 __PR((unsigned char * p));
static int  isonum_721 __PR((unsigned char * p));
static int  isonum_723 __PR((unsigned char * p));
static int  isonum_731 __PR((unsigned char * p));

static void DECL(free_directory_entry, (struct directory_entry * dirp));
static int  DECL(merge_old_directory_into_tree, (struct directory_entry *,
						 struct directory *));

#ifdef	__STDC__
static int
isonum_711 (unsigned char * p)
#else
static int
isonum_711 (p)
	unsigned char * p;
#endif
{
	return (*p & 0xff);
}

#ifdef	__STDC__
static int
isonum_721 (unsigned char * p)
#else
static int
isonum_721 (p)
	unsigned char * p;
#endif
{
	return ((p[0] & 0xff) | ((p[1] & 0xff) << 8));
}

#ifdef	__STDC__
static int
isonum_723 (unsigned char * p)
#else
static int
isonum_723 (p)
	unsigned char * p;
#endif
{
#if 0
	if (p[0] != p[3] || p[1] != p[2]) {
#ifdef	USE_LIBSCHILY
		comerrno(EX_BAD, "invalid format 7.2.3 number\n");
#else
		fprintf (stderr, "invalid format 7.2.3 number\n");
		exit (1);
#endif
	}
#endif
	return (isonum_721 (p));
}

#ifdef	__STDC__
static int
isonum_731 (unsigned char * p)
#else
static int
isonum_731 (p)
	unsigned char * p;
#endif
{
	return ((p[0] & 0xff)
		| ((p[1] & 0xff) << 8)
		| ((p[2] & 0xff) << 16)
		| ((p[3] & 0xff) << 24));
}

#ifdef	__STDC__
int
isonum_733 (unsigned char * p)
#else
int
isonum_733 (p)
	unsigned char * p;
#endif
{
	return (isonum_731 (p));
}

FILE * in_image = NULL;

#ifndef	USE_SCG
/*
 * Don't define readsecs if mkisofs is linked with
 * the SCSI library.
 * readsecs() will be implemented as SCSI command in this case.
 *
 * Use global var in_image directly in readsecs()
 * the SCSI equivalent will not use a FILE* for I/O.
 *
 * The main point of this pointless abstraction is that Solaris won't let
 * you read 2K sectors from the cdrom driver.  The fact that 99.9% of the
 * discs out there have a 2K sectorsize doesn't seem to matter that much.
 * Anyways, this allows the use of a scsi-generics type of interface on
 * Solaris.
 */
#ifdef	__STDC__
static int
readsecs(int startsecno, void *buffer, int sectorcount)
#else
static int
readsecs(startsecno, buffer, sectorcount)
	int	startsecno;
	void	*buffer;
	int	sectorcount;
#endif
{
	int	f = fileno(in_image);

	if (lseek(f, (off_t)startsecno * SECTOR_SIZE, 0) == (off_t)-1) {
#ifdef	USE_LIBSCHILY
		comerr(" Seek error on old image\n");
#else
		fprintf(stderr," Seek error on old image\n");
		exit(10);
#endif
	}
	if( read(f, buffer, (sectorcount * SECTOR_SIZE))
	    != (sectorcount * SECTOR_SIZE) )
	{
#ifdef	USE_LIBSCHILY
		comerr(" Read error on old image\n");
#else
		fprintf(stderr," Read error on old image\n");
		exit(10);
#endif
	}
	return sectorcount * SECTOR_SIZE;
}
#endif

/*
 * Parse the RR attributes so we can find the file name.
 */
static int 
FDECL3(parse_rr, unsigned char *, pnt, int, len, struct directory_entry *,dpnt)
{
	int cont_extent, cont_offset, cont_size;
	char name_buf[256];

	cont_extent = cont_offset = cont_size = 0;

	while(len >= 4){
		if(pnt[3] != 1 && pnt[3] != 2) {
#ifdef	USE_LIBSCHILY
		  errmsgno(EX_BAD, "**BAD RRVERSION (%d) for %c%c\n", pnt[3], pnt[0], pnt[1]);
#else
		  fprintf(stderr, "**BAD RRVERSION (%d) for %c%c\n", pnt[3], pnt[0], pnt[1]);
#endif
		  return -1;
		};
		if(strncmp((char *) pnt, "NM", 2) == 0) {
		  strncpy(name_buf, (char *) pnt+5, pnt[2] - 5);
		  name_buf[pnt[2] - 5] = 0;
		  dpnt->name = strdup(name_buf);
		  dpnt->got_rr_name = 1;
		  return 0;
		}

		if(strncmp((char *) pnt, "CE", 2) == 0) {
			cont_extent = isonum_733(pnt+4);
			cont_offset = isonum_733(pnt+12);
			cont_size = isonum_733(pnt+20);
		};

		len -= pnt[2];
		pnt += pnt[2];
		if(len <= 3 && cont_extent) {
		  unsigned char sector[SECTOR_SIZE];
		  readsecs(cont_extent, sector, 1);
		  if (parse_rr(&sector[cont_offset], cont_size, dpnt) == -1)
			return (-1);
		};
	};

	/* Fall back to the iso name if no RR name found */
	if (dpnt->name == NULL) {
	  char *cp;

	  strcpy(name_buf, dpnt->isorec.name);
	  cp = strchr(name_buf, ';');
	  if (cp != NULL) {
	    *cp = '\0';
	  }

	  dpnt->name = strdup(name_buf);
	}

	return 0;
} /* parse_rr */


/*
 * Returns 1 if the two files are identical
 * Returns 0 if the two files differ
 */
static int 
FDECL4(check_rr_dates, struct directory_entry *, dpnt, 
       struct directory_entry *, current, 
       struct stat *, statbuf, 
       struct stat *,lstatbuf)
{
	int cont_extent, cont_offset, cont_size;
	int offset;
	unsigned char * pnt;
	int len;
	int same_file;
	int same_file_type;
	mode_t mode;
	char time_buf[7];
	
	
	cont_extent = cont_offset = cont_size = 0;
	same_file = 1;
	same_file_type = 1;

	pnt = dpnt->rr_attributes;
	len = dpnt->rr_attr_size;
	/*
	 * We basically need to parse the rr attributes again, and
	 * dig out the dates and file types.
	 */
	while(len >= 4){
		if(pnt[3] != 1 && pnt[3] != 2) {
#ifdef	USE_LIBSCHILY
		  errmsgno(EX_BAD, "**BAD RRVERSION (%d) for %c%c\n", pnt[3], pnt[0], pnt[1]);
#else
		  fprintf(stderr, "**BAD RRVERSION (%d) for %c%c\n", pnt[3], pnt[0], pnt[1]);
#endif
		  return -1;
		};

		/*
		 * If we have POSIX file modes, make sure that the file type
		 * is the same.  If it isn't, then we must always
		 * write the new file.
		 */
		if(strncmp((char *) pnt, "PX", 2) == 0) {
		  mode = isonum_733(pnt + 4);
		  if( (lstatbuf->st_mode & S_IFMT) != (mode & S_IFMT) )
		    {
		      same_file_type = 0;
		      same_file = 0;
		    }
		}

		if(strncmp((char *) pnt, "TF", 2) == 0) {
		  offset = 5;
		  if( pnt[4] & TF_CREATE )
		    {
		      iso9660_date((char *) time_buf, lstatbuf->st_ctime);
		      if(memcmp(time_buf, pnt+offset, 7) != 0) 
			same_file = 0;
		      offset += 7;
		    }
		  if( pnt[4] & TF_MODIFY )
		    {
		      iso9660_date((char *) time_buf, lstatbuf->st_mtime);
		      if(memcmp(time_buf, pnt+offset, 7) != 0) 
			same_file = 0;
		      offset += 7;
		    }
		}

		if(strncmp((char *) pnt, "CE", 2) == 0) {
			cont_extent = isonum_733(pnt+4);
			cont_offset = isonum_733(pnt+12);
			cont_size = isonum_733(pnt+20);
		};

		len -= pnt[2];
		pnt += pnt[2];
		if(len <= 3 && cont_extent) {
		  unsigned char sector[SECTOR_SIZE];

		  readsecs(cont_extent, sector, 1);
		  if (parse_rr(&sector[cont_offset], cont_size, dpnt) == -1)
			return (-1);
		};
	};

	/*
	 * If we have the same fundamental file type, then it is clearly
	 * safe to reuse the TRANS.TBL entry.
	 */
	if( same_file_type )
	  {
	    current->de_flags |= SAFE_TO_REUSE_TABLE_ENTRY;
	  }

	return same_file;
}

struct directory_entry **
FDECL2(read_merging_directory, struct iso_directory_record *, mrootp,
       int *, nent)
{
  unsigned char			* cpnt;
  unsigned char			* cpnt1;
  char				* dirbuff;
  int				  i;
  struct iso_directory_record	* idr;
  int				  len;
  int				  nbytes;
  struct directory_entry	**pnt;
  int				  rlen;
  struct directory_entry	**rtn;
  int				  seen_rockridge;
  unsigned char			* tt_buf;
  int				  tt_extent;
  int				  tt_size;

  static int warning_given = 0;

  /*
   * This is the number of sectors we will need to read.  We need to
   * round up to get the last fractional sector - we are asking for
   * the data in terms of a number of sectors.
   */
  nbytes = roundup(isonum_733((unsigned char *)mrootp->size), SECTOR_SIZE);

  /*
   * First, allocate a buffer large enough to read in the entire
   * directory.
   */
  dirbuff = (char *) e_malloc(nbytes);

  readsecs(isonum_733((unsigned char *)mrootp->extent), dirbuff,
	   nbytes / SECTOR_SIZE);

  /*
   * Next look over the directory, and count up how many entries we
   * have.
   */
  len = isonum_733((unsigned char *)mrootp->size);
  i = 0;
  *nent = 0;
  while(i < len )
    {
      idr = (struct iso_directory_record *) &dirbuff[i];
      if(idr->length[0] == 0) 
	{
	  i = (i + SECTOR_SIZE - 1) & ~(SECTOR_SIZE - 1);
	  continue;
	}
      (*nent)++;
      i += idr->length[0];
    }

  /*
   * Now allocate the buffer which will hold the array we are
   * about to return.
   */
  rtn = (struct directory_entry **) e_malloc(*nent * sizeof(*rtn));

  /*
   * Finally, scan the directory one last time, and pick out the
   * relevant bits of information, and store it in the relevant
   * bits of the structure.
   */
  i = 0;
  pnt = rtn;
  tt_extent = 0;
  seen_rockridge = 0;
  tt_size = 0;
  while(i < len )
    {
      idr = (struct iso_directory_record *) &dirbuff[i];
      if(idr->length[0] == 0) 
	{
	  i = (i + SECTOR_SIZE - 1) & ~(SECTOR_SIZE - 1);
	  continue;
	}
      *pnt = (struct directory_entry *) e_malloc(sizeof(**rtn));
      (*pnt)->next = NULL;
      (*pnt)->isorec = *idr;
      (*pnt)->starting_block = isonum_733((unsigned char *)idr->extent);
      (*pnt)->size = isonum_733((unsigned char *)idr->size);
      (*pnt)->priority = 0;
      (*pnt)->name = NULL;
      (*pnt)->got_rr_name = 0;
      (*pnt)->table = NULL;
      (*pnt)->whole_name = NULL;
      (*pnt)->filedir = NULL;
      (*pnt)->parent_rec = NULL;
      /*