write.c

一款功能很强的光盘镜象制作工具

/*
 * Program write.c - dump memory  structures to  file for iso9660 filesystem.

   Written by Eric Youngdale (1993).

   Copyright 1993 Yggdrasil Computing, Incorporated

   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: write.c,v 1.21 1999/03/07 17:41:19 eric Exp $";

#include <string.h>
#include <stdlib.h>
#include "config.h"
#include "mkisofs.h"
#include "iso9660.h"
#include <time.h>
#include <errno.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "foolhash.h"
#include "md5.h"

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
 
#ifdef __SVR4
extern char * strdup(const char *);
#endif

#ifdef VMS
extern char * strdup(const char *);
#endif

extern struct hash_table *md5_hash;

/* Max number of sectors we will write at  one time */
#define NSECT 16

/* Counters for statistics */

static int table_size       = 0;
static int total_dir_size   = 0;
static int rockridge_size   = 0;
static struct directory ** pathlist;
static int next_path_index  = 1;
static int sort_goof;

struct output_fragment * out_tail;
struct output_fragment * out_list;

struct iso_primary_descriptor vol_desc;

static int root_gen	__PR((void));
static int generate_path_tables	__PR((void));
static int file_gen	__PR((void));
static int dirtree_dump	__PR((void));

/* Routines to actually write the disc.  We write sequentially so that
   we could write a tape, or write the disc directly */


#define FILL_SPACE(X)   memset(vol_desc.X, ' ', sizeof(vol_desc.X))

void FDECL2(set_721, char *, pnt, unsigned int, i)
{
     pnt[0] = i & 0xff;
     pnt[1] = (i >> 8) &  0xff;
}

void FDECL2(set_722, char *, pnt, unsigned int, i)
{
     pnt[0] = (i >> 8) &  0xff;
     pnt[1] = i & 0xff;
}

void FDECL2(set_723, char *, pnt, unsigned int, i)
{
     pnt[3] = pnt[0] = i & 0xff;
     pnt[2] = pnt[1] = (i >> 8) &  0xff;
}

void FDECL2(set_731, char *, pnt, unsigned int, i)
{
     pnt[0] = i & 0xff;
     pnt[1] = (i >> 8) &  0xff;
     pnt[2] = (i >> 16) &  0xff;
     pnt[3] = (i >> 24) &  0xff;
}

void FDECL2(set_732, char *, pnt, unsigned int, i)
{
     pnt[3] = i & 0xff;
     pnt[2] = (i >> 8) &  0xff;
     pnt[1] = (i >> 16) &  0xff;
     pnt[0] = (i >> 24) &  0xff;
}

int FDECL1(get_733, char *, p)
{
     return ((p[0] & 0xff)
	     | ((p[1] & 0xff) << 8)
	     | ((p[2] & 0xff) << 16)
	     | ((p[3] & 0xff) << 24));
}

void FDECL2(set_733, char *, pnt, unsigned int, i)
{
     pnt[7] = pnt[0] = i & 0xff;
     pnt[6] = pnt[1] = (i >> 8) &  0xff;
     pnt[5] = pnt[2] = (i >> 16) &  0xff;
     pnt[4] = pnt[3] = (i >> 24) &  0xff;
}

void FDECL4(xfwrite, void *, buffer, int, count, int, size, FILE *, file)
{
	/*
	 * This is a hack that could be made better. XXXIs this the only place?
	 * It is definitely needed on Operating Systems that do not
	 * allow to write files that are > 2GB.
	 * If the system is fast enough to be able to feed 1400 KB/s
	 * writing speed of a DVD-R drive, use stdout.
	 * If the system cannot do this reliable, you need to use this
	 * hacky option.
	 */
	static	int	idx = 0;
	if (split_output != 0 &&
	    (idx == 0 || ftell(file) >= (1024 * 1024 * 1024) )) {
			char	nbuf[512];
		extern	char	*outfile;

		if (idx == 0)
			unlink(outfile);
		sprintf(nbuf, "%s_%02d", outfile, idx++);
		file = freopen(nbuf, "wb", file);
		if (file == NULL) {
			fprintf(stderr, "Cannot open '%s'.\n", nbuf);
			exit(1);
		}

	}
     while(count) 
     {
	  int got = fwrite(buffer,size,count,file);

	  if(got<=0) 
	  {
	       fprintf(stderr,"cannot fwrite %d*%d\n",size,count);
	       exit(1);
	  }
	  count-=got,*(char**)&buffer+=size*got;
     }
}

struct deferred_write
{
  struct deferred_write * next;
  char			* table;
  unsigned int		  extent;
  unsigned int		  size;
  char			* name;
};

static struct deferred_write * dw_head = NULL, * dw_tail = NULL;

unsigned int last_extent_written  =0;
static int path_table_index;
static time_t begun;

/* We recursively walk through all of the directories and assign extent
   numbers to them.  We have already assigned extent numbers to everything that
   goes in front of them */

static int FDECL1(assign_directory_addresses, struct directory *, node)
{
     int		dir_size;
     struct directory * dpnt;

     dpnt = node;
     
     while (dpnt)
     {
	  /* skip if it's hidden */
	  if(dpnt->dir_flags & INHIBIT_ISO9660_ENTRY) {
	     dpnt = dpnt->next;
	     continue;
	  }

	  /*
	   * If we already have an extent for this (i.e. it came from
	   * a multisession disc), then don't reassign a new extent.
	   */
	  dpnt->path_index = next_path_index++;
	  if( dpnt->extent == 0 )
	  {
	       dpnt->extent = last_extent;
	       dir_size = (dpnt->size + (SECTOR_SIZE - 1)) >> 11;
	       
	       last_extent += dir_size;
	       
	       /* 
		* Leave room for the CE entries for this directory.  Keep them
		* close to the reference directory so that access will be 
		* quick. 
		*/
	       if(dpnt->ce_bytes)
	       {
		    last_extent += ROUND_UP(dpnt->ce_bytes) >> 11;
	       }
	  }

	  if(dpnt->subdir) 
	  {
	       assign_directory_addresses(dpnt->subdir);
	  }

	  dpnt = dpnt->next;
     }
     return 0;
}

static void FDECL3(write_one_file, char *, filename, 
		   unsigned int, size, FILE *, outfile)
{
     char		  buffer[SECTOR_SIZE * NSECT];
     FILE		* infile;
     int		  remain;
     int		  use;


     if ((infile = fopen(filename, "rb")) == NULL) 
     {
#if defined(sun) || defined(_AUX_SOURCE)
	  fprintf(stderr, "cannot open %s: (%d)\n", filename, errno);
#else
	  fprintf(stderr, "cannot open %s: %s\n", filename, strerror(errno));
#endif
	  exit(1);
     }
     remain = size;

     while(remain > 0)
     {
	  use =  (remain >  SECTOR_SIZE * NSECT - 1 ? NSECT*SECTOR_SIZE : remain);
	  use = ROUND_UP(use); /* Round up to nearest sector boundary */
	  memset(buffer, 0, use);
	  if (fread(buffer, 1, use, infile) == 0) 
	  {
		fprintf(stderr,"cannot read from %s\n",filename); 
		exit(1);
	  }
	  xfwrite(buffer, 1, use, outfile);
	  last_extent_written += use/SECTOR_SIZE;
#if 0
	  if((last_extent_written % 1000) < use/SECTOR_SIZE) 
	  {
	       fprintf(stderr,"%d..", last_extent_written);
	  }
#else
	  if((last_extent_written % 5000) < use/SECTOR_SIZE)
	  {
	       time_t now;
	       time_t the_end;
	       double frac;
	       
	       time(&now);
	       frac = last_extent_written / (double)last_extent;
	       the_end = begun + (now - begun) / frac;
	       fprintf(stderr, "%6.2f%% done, estimate finish %s",
		       frac * 100., ctime(&the_end));
	  }
#endif
	  remain -= use;
     }
     fclose(infile);
} /* write_one_file(... */

static void FDECL1(write_files, FILE *, outfile)
{
     struct deferred_write * dwpnt, *dwnext;
     dwpnt = dw_head;
     while(dwpnt)
     {
	  if(dwpnt->table) 
	  {
	       xfwrite(dwpnt->table,  1, ROUND_UP(dwpnt->size), outfile);
	       last_extent_written += ROUND_UP(dwpnt->size) / SECTOR_SIZE;
	       table_size += dwpnt->size;
/*		  fprintf(stderr,"Size %d ", dwpnt->size); */
	       free(dwpnt->table);
	  } 
	  else 
	  {

#ifdef VMS
	       vms_write_one_file(dwpnt->name, dwpnt->size, outfile);
#else
	       write_one_file(dwpnt->name, dwpnt->size, outfile);
#endif
	       free(dwpnt->name);
	  }

	  dwnext = dwpnt;
	  dwpnt = dwpnt->next;
	  free(dwnext);
     }
} /* write_files(... */

#if 0
static void dump_filelist()
{
     struct deferred_write * dwpnt;
     dwpnt = dw_head;
     while(dwpnt)
     {
	  fprintf(stderr, "File %s\n",dwpnt->name);
	  dwpnt = dwpnt->next;
     }
     fprintf(stderr,"\n");
}
#endif

static int FDECL2(compare_dirs, const void *, rr, const void *, ll) 
{
     char * rpnt, *lpnt;
     struct directory_entry ** r, **l;
     
     r = (struct directory_entry **) rr;
     l = (struct directory_entry **) ll;
     rpnt = (*r)->isorec.name;
     lpnt = (*l)->isorec.name;

     /*
      * If the entries are the same, this is an error.
      */
     if( strcmp(rpnt, lpnt) == 0 )
       {
	 sort_goof++;
       }
     
     /*
      *  Put the '.' and '..' entries on the head of the sorted list.
      *  For normal ASCII, this always happens to be the case, but out of
      *  band characters cause this not to be the case sometimes.
      *
      * FIXME(eric) - these tests seem redundant, in taht the name is
      * never assigned these values.  It will instead be \000 or \001,
      * and thus should always be sorted correctly.   I need to figure
      * out why I thought I needed this in the first place.
      */
#if 0
     if( strcmp(rpnt, ".") == 0 ) return -1;
     if( strcmp(lpnt, ".") == 0 ) return  1;

     if( strcmp(rpnt, "..") == 0 ) return -1;
     if( strcmp(lpnt, "..") == 0 ) return  1;
#else
     /*
      * The code above is wrong (as explained in Eric's comment), leading to incorrect
      * sort order iff the -L option ("allow leading dots") is in effect and a directory
      * contains entries that start with a dot.
      *
      * (TF, Tue Dec 29 13:49:24 CET 1998)
      */
     if((*r)->isorec.name_len[0] == 1 && *rpnt == 0) return -1; /* '.' */
     if((*l)->isorec.name_len[0] == 1 && *lpnt == 0) return 1;

     if((*r)->isorec.name_len[0] == 1 && *rpnt == 1) return -1; /* '..' */
     if((*l)->isorec.name_len[0] == 1 && *lpnt == 1) return 1;
#endif

     while(*rpnt && *lpnt) 
     {
	  if(*rpnt == ';' && *lpnt != ';') return -1;
	  if(*rpnt != ';' && *lpnt == ';') return 1;
	  
	  if(*rpnt == ';' && *lpnt == ';') return 0;
	  
	  if(*rpnt == '.' && *lpnt != '.') return -1;
	  if(*rpnt != '.' && *lpnt == '.') return 1;
	  
	  if((unsigned char)*rpnt < (unsigned char)*lpnt) return -1;
	  if((unsigned char)*rpnt > (unsigned char)*lpnt) return 1;
	  rpnt++;  lpnt++;
     }
     if(*rpnt) return 1;
     if(*lpnt) return -1;
     return 0;
}

/* 
 * Function:		sort_directory
 *
 * Purpose:		Sort the directory in the appropriate ISO9660
 *			order.
 *
 * Notes:		Returns 0 if OK, returns > 0 if an error occurred.
 */
int FDECL1(sort_directory, struct directory_entry **, sort_dir)
{
     int dcount = 0;
     int xcount = 0;
     int j;
     int i, len;
     struct directory_entry * s_entry;
     struct directory_entry ** sortlist;
     
     /* need to keep a count of how many entries are hidden */
     s_entry = *sort_dir;
     while(s_entry)
     {
	  if (s_entry->de_flags & INHIBIT_ISO9660_ENTRY)
	    xcount++;
	  dcount++;
	  s_entry = s_entry->next;
     }

     if( dcount == 0 )
     {
          return 0;
     }

     /*
      * OK, now we know how many there are.  Build a vector for sorting. 
      */
     sortlist =   (struct directory_entry **) 
	  e_malloc(sizeof(struct directory_entry *) * dcount);

     j = dcount - 1;
     dcount = 0;
     s_entry = *sort_dir;
     while(s_entry)
     {
	if(s_entry->de_flags & INHIBIT_ISO9660_ENTRY)
	 {
	  /* put any hidden entries at the end of the vector */
	  sortlist[j--] = s_entry;
	 }
	else
	 {
	  sortlist[dcount] = s_entry;
	  dcount++;
	 }
	 len = s_entry->isorec.name_len[0];
	 s_entry->isorec.name[len] = 0;
	 s_entry = s_entry->next;
     }
  
     /*
      * Each directory is required to contain at least . and ..
      */
     if( dcount < 2 )
       {
	 sort_goof = 1;
	 
       }
     else
       {
	 /* only sort the non-hidden entries */
	 sort_goof = 0;
#ifdef __STDC__
	 qsort(sortlist, dcount, sizeof(struct directory_entry *), 
	       (int (*)(const void *, const void *))compare_dirs);
#else
	 qsort(sortlist, dcount, sizeof(struct directory_entry *), 
	       compare_dirs);
#endif
	 
	 /* 
	  * Now reassemble the linked list in the proper sorted order 
	  * We still need the hidden entries, as they may be used in the
	  * Joliet tree.
	  */
	 for(i=0; i<dcount+xcount-1; i++)
	   {
	     sortlist[i]->next = sortlist[i+1];
	   }