/*
    dds2tar  Digital-Data-Storage Extract Tool

             This tool makes use of the fast seek command of DAT devices.
             Files from a selected file archive can be extracted within
             one minute.

             J"org Weule                     weule@cs.uni-duesseldorf.de
                                             Fon: +49 211 751409

----------------------------------------------------------------------------

                              LICENSE

    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 1, 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.

----------------------------------------------------------------------------

    To anyone in Germany I declare the following:

    !  Ich werde gegen jede Verbreitung dieser Software rechtlich        !
    !  vorgehen, welche die Lizenzbestimmungen nicht einh"alt.           !

       Wie f"ur jede andere Software gilt auch hier:
       Schon mit dem Kopieren oder Benutzen von Teilen dieser Software
       werden die Lizenzbedingungen stillschweigend akzeptiert. Lesen Sie
       also die Lizenzbedingungen sorgf"altig! Unkenntnis sch"utzt nicht
       vor Strafe.

*/

/*-------------------------------------------------------------------------*/

#include <stdlib.h>		/* getenv() */
#include <stdio.h>
#include <string.h>		/* strcmp() strlen() strstr() */
#include <sys/types.h>		/* open() stat() */
#include <sys/stat.h>		/* stat() */
#include <fcntl.h>		/* open() */
#include <unistd.h>		/* open() */
#include <time.h>		/* ctime() */

#include "dds2tar.h"
#include "dds_tape.h"
#include "zf-cre-open.h"

char vendor[9] = "\0\0\0\0\0\0\0\0\0" ;
int vid; /* vendor id */

/*-------------------------------------------------------------------------*/

static const char help_text_dds2index[] =
"This is dds2index, a tool for fast tape access.\n"
"Choose one of the following\n"
"-t,--table-of-contents F  get file location from file F\n"
"-z,--compress           filter location file through gzip\n"
"--z,--no-compress       don't filter location file through gzip\n"
"-f,--device F           read the archive from device F\n"
"-b,--block-size #       set block size (non HP/SONY)\n"
"-B,--Block-size #       set block size (HP or SONY)\n"
"-q,--quick              don't extract parent directories from tape\n"
"-v,--verbose            verbose mode\n"
"--hash-mode             hash mode\n"
"--force                 force nochk\n"
"--help                  get help\n"
"-V,--version            print version number\n"
"\n"
"Environment:\n"
"TAPE                    specifies the tape device\n"
"DDS2TAR=[--compress] [-z] [-s #] [-b #]\n"
"                        set some defaults\n"
       ;

static const char help_text_dds2tar[] =
"This is dds2tar, a tool for fast tape access.\n"
"Usage: dds2tar [options... ] -t index [pathname ...]  | tar -f - ...\n"
"\n"
"dds2tar is a tool to read some tar-records from tape and write them\n"
"as a tar archive to stdout. You have to use tar to extract the\n"
"selected files. The index can either be created by dds2tar or tar.\n"
"\n"
"Choose one of the following\n"
"-t,--table-of-contents F  get file location from file F\n"
"-z,--compress           filter location file through gzip\n"
"--z,--no-compress       don't filter location file through gzip\n"
"-f,--device F           read the archive from device F\n"
"-o,--output F           write output to archive file\n"
"-b,--block-size #       set block size (non HP/SONY)\n"
"-B,--Block-size #       set block size (HP or SONY)\n"
"-s,--first_block #      set number of the first block\n"
"--body                  print only the contents of the first file an quit\n"
"-v,--verbose            verbose mode\n"
"--help                  get help\n"
"-V,--version            print version number\n"
"\n"
"Environment:\n"
"TAPE                    specifies the tape device\n"
"DDS2TAR=[--compress] [-z] [-s #] [-b #]\n"
"                        set some defaults\n"
       ;

static const char help_text_mt_dds[] =
"This is mt-dds, a tool to control the dds-device.\n"
"Usage: mt-dds [-f device] <action>\n"
"\n"
"Choose one or none of the following actions:\n"
#ifdef HPDAT
"comp-on      set compression mode on\n"
"comp-off     set compression mode off\n"
"comp-query   query compression mode\n"
"comp-log     print compression log page\n"
#endif
"-b           set the buffer size\n"
"blksize      print the block size of the archive with format\n"
"tell         print current location and blocksize\n"
"where        print current location\n"
"label        print the label of the current archive\n"
"             if it begins at the current position\n"
"filename     print the filename of the current record\n"
"             if a header record is found at the current position\n"
"ts           print the timestamp of the current archive\n"
"date         print the date of the current archive\n"
"scsi2logical select mode scsi2logical first\n"
"             if it begins at the current position\n"
"date <timestamp> convert the stamp to a string\n"
       ;

static const char help_text_dds_dd[] =
"This is dds-dd, a tool to read the dds-device.\n"
"Usage: dds-dd` [-f device] | tar -f - -[x|t] ... \n";

/*-------------------------------------------------------------------------*/

static const char version[] =
"Version " VERSION " -- last change 1994 Dez 22." ;

/*-------------------------------------------------------------------------*/

/* This is the source for dds2tar, dds2index and mt-dds. The program will
   use the variable pg to decide witch version is running. The default
   can be set in the Makefile and is overwritten by the value of argv[0].
   If you give --dds2tar, --dds2index or --mt-dds as an option, the
   program will run instead of these.
*/

#define DDS2TAR name_dds2tar
static char const name_dds2tar[] = "dds2tar";

#define DDS2INDEX name_dds2index
static char const name_dds2index[] = "dds2index";

#define MTDDS name_mtdds
static char const name_mtdds[] = "mt-dds";

#define DDS_DD name_dds_dd
static char const name_dds_dd[] = "dds-dd";


#if ( PROGRAM == DDS2TAR )
char const *pg = name_dds2tar;
char const *help_text = help_text_dds2tar;

#elif ( PROGRAM == DDS2INDEX )
char const *pg = name_dds2index;
char const *help_text = help_text_dds2index;

#elif ( PROGRAM == DDS2TAR )
char const *pg = name_mtdds;
char const *help_text = help_text_mt_dds;

#elif ( PROGRAM == DDS_DD )
char const *pg = name_dds_dd;
char const *help_text = help_text_dds_dd;

#else
char const *pg = name_dds2tar;
char   *help_text = help_text_dds2tar;

#endif

#define LOCATION 1
#define EXTRACT 2

/*-------------------------------------------------------------------------*/

char const dds_old_headline[] =
"magic record blk:     size name\n";

char const dds_old_index_format[] =
"%6s%7d%3d:%9d %s\n";

/* magic blkno recno: size name */

char const dds_old_index_scan_format[] =
"%6c%7d%3d:%9d\n";

char const dds_headline[] =
"magic  record blk:     size name\n";

char const dds_index_format[] =
"%6s%7d%4d:%9d %s\n";

/* magic blkno recno: size name */

char const dds_index_scan_format[] =
"%6c%7d%4d:%9d\n";

/* magic blkno recno: size name */

char const dds_loctext[] =
"first block number is %d\n"
"block size is %d\n" "block length is %d\n";

char const dds_locline1[] =
"loc             number of the first block is %d\n";

char const dds_locline2[] =
"loc             block length is %d bytes = %d * 512 bytes\n";

/* to handle long link and long file names */
int long_name_len = 0 ;
char long_name[MAXPATHLEN<<2] = { '\0' };

int
rt_loc_line(void)
{
	int     i;

	if ((i = strncmp(cur_line, dds_locline1, 45)) == 0) {
		tar_fb = atoi(cur_line + 45);
	} else if ((i = strncmp(cur_line, "first block number is", 21)) == 0) {
		tar_fb = atoi(cur_line + 21);
	} else if ((i = strncmp(cur_line, dds_locline2, 31)) == 0) {
		tar_n = atoi(cur_line + 31);
		tar_bs = tar_n >> 9;
	} else if ((i = strncmp(cur_line, "block size is", 13)) == 0) {
		tar_bs = atoi(cur_line + 13);
		tar_n = tar_bs << 9;
	} else
		return 1;
	if ( buf_n < tar_n ) {
		cur_block = realloc ( cur_block , buf_n = tar_n );
		if ( cur_block == NULL ) {
			fprintf(stderr, "%s: No memory available.\n", pg);
			exit(2);
		}
	}
	return 0;
}


/*-------------------------------------------------------------------------*/

int     verbose = 0;
int     hash_mode = 0;
int     list_only = 0;		/* print only the matched names */
int	quick_mode = 0;		/* don't extract parent directories also */
int     device;			/* file number of the device */
int	write_body = 0 ;	/* write only the body of the first file */
int	get_label = 0 ;		/* get the label of the archive */
int	get_filename = 0 ;	/* get the filename of the current record */
int	get_blocksize = 0 ;	/* get the blocksize of the current record */
int	get_timestamp = 0 ;	/* get the timestamp of the archive */
int	get_date = 0 ;		/* get the date of the archive */
int	get_fileno = 0 ;	/* get the number of the current */
int	force_nochk = 0 ;	/* force tape read, no check of headers */

/* file io */
FILE   *index_fp = NULL;

/* archive location as set by arguments or index file */
int     tar_fb = 0;		/* first block of the archive */
int     tar_bs = 20;		/* block size in records of 512 bytes */
int     tar_n = 10240;		/* block length in bytes */

/* archive buffer and location as set by tape access */
tar_record *cur_block;
int     cur_blkno = -1;
int	next_blkno = -1 ;
int     cur_bs;
int     cur_n;
int	buf_n = ST_BUFFER_BLOCKS << 10 ;

/* line buffer to scan the index file */
char   *cur_line;

/*-------------------------------------------------------------------------*/

/********
	*  input: name of the device ( e.g. /dev/nst0, /dev/nrmt0 or NULL )
	*         open mode of the device ( e.g. O_RDONLY or O_WRONLY )
	*         verbose flag to indicate the logging mode (integer)
	* output: channel number ( integer ) for use with 'read()' or 'write()'
        *
        * side effects: none
	*
	**********************************************************************/

static int
open_device(char const *pathname, int const open_mode)
{
	int     fd;
	int     i = 1;
	char   const *p = "next try to open the tape %s\n";

	{
		int i ;
		struct stat s ;
		FILE *f ;
		char cmd[100];
		i = stat(pathname,&s);
		if ( i < 0 ) perror("dds2tar"),exit(1);
		sprintf(cmd,"scsi_vendor tape %d",(int)(s.st_rdev&0x7f)+1);
		f = popen(cmd,"r");
		fread(vendor,1,8,f);
		fclose(f);
		for ( i = 0 ; i < 8 ; i++ )
			( vendor[i] < 0x20 ) && ( vendor[i] = '\0' ) ;
		if ( !strcmp(vendor,"HP") ) vid = HP ;
		if ( !strcmp(vendor,"SONY") ) vid = SONY ;
		if ( !strcmp(vendor,"ARCHIVE") ) vid = ARCHIVE ;
		if ( !strcmp(vendor,"SEGATE") ) vid = SEGATE ;
		if ( !strcmp(vendor,"EXABYTE") ) vid = EXABYTE ;
	}
		
	do {
		if ((fd = open(pathname, open_mode)) >= 0)
			break;
		sleep(2);
		if (verbose)
			fprintf(stderr, p, pathname);
	} while ((++i) <= 15);
	if (fd < 0) {
		perror("tape busy?");
		exit(1);
	} /* else dds_has_partitions(fd); */
	return fd;
}

/*-------------------------------------------------------------------------*/
int
strprefix(char**s,char*p,char*q){
	while ( p != 0 ) {
		char *t = *s ; while (( *p != 0 ) && ( *p == *t )) p++ , t++ ;
		if ( *p == 0 ) { *s = t ; return 1 ; }
		p = q ; q = NULL ;
	} return 0 ;
}
/*-------------------------------------------------------------------------*/

/*
 * dds2tar
 */
int
main(int argc, char const *const *argv)
{

#ifndef DEVICE
#define DEVICE "/dev/rmt0"
#endif

	int	density = 0 ;
	int     n = 1;
	int     l = strlen(argv[0]);
	int     compressed_mode = T_MODE;
	char   *p;
	int     child_proc = -1;/* child not running */
	char const *index_file = NULL;
	int     print_location = 0;
	int     print_blksize = 0;
	int     mt_action = DDSCM_NULL;	/* turn compression on/off */
	int     mode = 0;	/* mode of dds2tar */
	char const *const *pattern_list = NULL;
	char const *device_name = DEVICE;

	if ((p = getenv("TAPE")) != NULL)
		device_name = p;

	if (!strcmp(argv[0] + l - 7, "dds2tar")) {
		pg = DDS2TAR;
		help_text = help_text_dds2tar;
	}
	if (!strcmp(argv[0] + l - 9, "dds2index")) {
		pg = DDS2INDEX;
		help_text = help_text_dds2index;
	}
	if (!strcmp(argv[0] + l - 6, "mt-dds")) {
		pg = MTDDS;
		help_text = help_text_mt_dds;
	}
	if (!strcmp(argv[0] + l - 6, "dds-dd")) {
		pg = DDS_DD;
		help_text = help_text_dds_dd;
	}

	/*
	 * Scanning the environment.
	 */
	p = getenv("DDS2TAR");
	while (p != NULL) {
		int count = 0 ;
		if (*p == ' ') p++;
		if ( *p == '\0' ) p = NULL ;
		else if (strprefix(&p, "-z","--compress")) {
			compressed_mode = C_MODE;
		} else if (strprefix(&p, "--first-block ","-s")) {
			sscanf(p, "%d%n", &tar_fb, &count);
			p += count;
		} else if (strprefix(&p, "--block-size ","-b ")){
			sscanf(p, "%d%n", &tar_bs, &count);
			tar_n = tar_bs * 512 ;
			buf_n = tar_n ;
			p += count;
		} else if (strprefix(&p, "--Block-size ","-B ")){
			sscanf(p, "%d%n", &tar_bs, &count);
			tar_n = tar_bs * 512 ;
			buf_n = tar_n ;
			p += count;
			density = tar_n ;
		} else
			p = NULL;
	}

	/*
	 * scan arguments
	 */
	while (n < argc) {

		/*
		 * Macros to test arguments ...
		 */

#define T1(s)        if((!strcmp(argv[n],(s))))
#define T(s)    else if((!strcmp(argv[n],(s))))
#define TT(s,t) else if((!strcmp(argv[n],(s)))||(!strcmp(argv[n],(t))))
#define ELSE    else
#define ELSEIF(s) else if(s)

		/*
		 * Now scanning the arguments ...
		 */

		T1("-0") {
			fprintf(stdout, "dds2tar: %s\n", argv[0]);
			exit(0);
		}

		/*
		 * misc
		 */
		T("--help") {
			fprintf(stdout, help_text);
			exit(0);
		}
		TT("--version", "-V") {
			fprintf(stdout, "%s: %s\n", pg, version);
			exit(0);
		}

		/*
		 * Some more options ...
		 */
		TT("--verbose", "-v") verbose = 1;
		T("--hash-mode") hash_mode = 1;
		T("--force") force_nochk = 1;

		/*
		 * device name
		 */
		T("-f") device_name = argv[++n];

		/*
		 * index file
		 */
		TT("-z", "--compress") compressed_mode = C_MODE;
		TT("--z", "--no-compress") compressed_mode = T_MODE;
		TT("-t", "--table-of-contents") {
			index_file = argv[++n];
			/*
			 * The format of the index is checked by the program.
			 */
		}

		/*
		 * Location of the file
		 */
		TT("-s", "--first-block") {
			tar_fb = atoi(argv[++n]);
		}
		TT("-b", "--block-size") {
			tar_bs = atoi(argv[++n]);
			tar_n = tar_bs * 512 ;
			buf_n = tar_n ;
		}
		TT("-B", "--Block-size") {
			tar_bs = atoi(argv[++n]);
			tar_n = tar_bs * 512 ;
			buf_n = tar_n ;
			density = tar_n ;
		}
		TT("-m", "--buffer-size") {
			fprintf(stderr,"buffer size is %d records, %d bytes\n",
				buf_n>>9,buf_n);
			exit(0);
		}

		ELSEIF(pg == DDS2TAR) {
			/*
			 * Mode of the program.
			 *
			 * If you install dds2tar as mt-dds, the program will
			 * act as mt-dds. Since for some operations you need
			 * root permissions on mt-dds, it would not be a good
			 * idea to let the user switch to dds2index or dds2tar
			 * in this case.
			 */

			T1("--dds2index") {
				pg = DDS2INDEX;

				help_text = help_text_dds2index;
			}
			T("--mt-dds") {
				pg = MTDDS;
				help_text = help_text_mt_dds;
			}
			T("--dds-dd") {
				pg = DDS_DD;
				help_text = help_text_dds_dd;
			}
			/*
			 * Mode of extraction ...
			 *
			 * The location list an experimental mode.
			 */
#ifdef EXP_STUFF
			T("--location-list") {
				pattern_list = argv + n + 1;
				mode = LOCATION;
				break;
			}
#endif
			/*
			 * Select a file for the output.
			 *
			 * Since mt-dds may be run as root, we write on screen
			 * in this case. Writing to a file is supported for
			 * dds2tar.
			 */
			TT("-o", "--output") {
				reopen(1, argv[++n], O_WRONLY | O_CREAT, 0660);
			}

			/*
			 * Do not read anything from tape.
			 */
			TT("-l", "--list") {
				list_only = 1;
				if (verbose)
					fputs("--list\n", stderr);
			}
			/*
			 * Write only the body of the file.
			 */
			T("--body"){
				write_body = 1 ;
			}

			/*
			 * Don't extract the parent directories from the tape.
			 */
			TT("-q","--quick"){
				quick_mode = 1 ;
			}
			/*
			 * Pipe the output to tar -x.
			 *
			 * This is for testing only.
			 */
			T("--test") {
				static char const *const a[5] =
				{
					"/bin/tar", "tfb", "-", "1", NULL
				};

				child_proc = creopen(1, 0, a[0], a);
			}
			T("--test-verbose") {
				static char const *const a[5] =
				{
					"/bin/tar", "tfbv", "-", "1", NULL
				};

				child_proc = creopen(1, 0, a[0], a);
			}
			T("--extract") {
				static char const *const a[5] =
				{
					"/bin/tar", "xfb", "-", "1", NULL
				};

				child_proc = creopen(1, 0, a[0], a);
			}
			ELSE {
				pattern_list = argv + n;
				if (verbose)
					fprintf(stderr,
						"first pattern is '%s'\n",
						*pattern_list
						);
				mode = EXTRACT;
				break;
			}
		}

		ELSEIF(pg == MTDDS) {
			/*
			 * Tape actions ...
			 */
			T1("tell") print_location = 1;
			T("label") get_label = 1 ;
			T("filename") get_filename = 1 ;
			T("bs") get_blocksize = 1 ;
			T("date") {
				get_date = 1 ;
				if ( argc > 2 ) {
					int j = atoi(argv[2]);
					fputs(ctime((time_t*)&j),stdout);
					exit(0);
				}
			}
			T("ts") get_timestamp = 1 ;
			T("blksize") print_blksize = 1 ;
#ifdef HPDAT
#define R(c) if ( 0 != geteuid() ) { fprintf(stderr,\
"You have to be root to do this : %s\n",c);exit(1);}
			T("comp-on") {
				R("comp-on");
				mt_action = DDSCM_ON;
			}
			T("comp-off") {
				R("comp-off");
				mt_action = DDSCM_OFF;
			}
			T("comp-query") {
				R("comp-query");
				mt_action = DDSCM_QUERY;
			}
			T("comp-log") {
				R("comp-log");
				mt_action = DDSCM_LOG;
			}
			T("load") {
				R("comp-load");
				mt_action = DDSCM_LOAD;
			}
			T("unload") {
				R("comp-unload");
				mt_action = DDSCM_UNLOAD;
			}
			T("where") {
				mt_action = DDSCM_WHERE;
			}
			/*
			 * Set mode scsi2logical first
			 */
			T("scsi2logical"){
				mt_action = DDSCM_LOGICAL;
			}

#endif
#ifdef EXP_STUFF
			/*
		 * tar-dds will handle the arguments in a very different way.
		 */
		}
		ELSEIF(pg == TAR_DDS) {

			break;
#endif
		}
		/*
		 * Next argument ...
		 */
		n++;
	}

	cur_block = malloc(buf_n);
	cur_line = malloc(MAXPATHLEN<<2);
	if (cur_block == NULL || cur_line == NULL) {
		fprintf(stderr, "%s: No memory available.\n", pg);
		exit(2);
	}
	/*
	 * Switch the program mode ... dds2tar, dds2index or mt-dds ...
	 */
	/*---------------------MT-DDS--------------------------------*/
	if (pg == MTDDS) {
#ifdef HPDAT
		/*
		 * Is setting of compression mode or log page selected ?
		 *
		 * I think you have to run this as root.
		 */
		if (mt_action != DDSCM_NULL) {
			device = open_device(device_name, O_WRONLY);
			if ( mt_action == DDSCM_LOGICAL )
				dds_scsi2logical();
			else
			if ( mt_action == DDSCM_WHERE ) {
				tar_fb = dds_getpos(device);
				printf(" -s %d \n", tar_fb);
				close(device);
				return 0;
			} else
				set_compression_mode(device, mt_action);
		} else
#endif
		/*
		 * Print the current position (tree lines).
		 */
		{
			device = open_device(device_name, O_RDONLY);
			if ( vid == HP ){
				tar_fb = dds_getpos(device);
				dds_read_next_block();
				/* dds_seek(device, tar_fb); */
				dds_bsr();
			} else {
				tar_fb = dds_getpos(device);
				cur_n = tar_n ;
			}
			tar_bs = cur_n >> 9;
			if (( get_label || get_timestamp ||
				get_date || get_filename ) &&
				( dds_is_tar_header_record(cur_block) != 0 )) {
				if ( cur_block->hdr.linkflag == 'V' ) {
					int i , j = 0 ;
					char*p=cur_block->hdr.mtime ;
					for ( i = 0 ; i < 12 ; i++ ) {
						if ((p[i]>='0')&&(p[i]<='7')) {
							j <<= 3 ;
							j += p[i] - '0' ;
						}
					}
					if ( get_label )
						puts(cur_block->hdr.name);
					else if ( get_timestamp ){
						printf("%d\n",j);
					} else /* get_date */ {
						fputs(ctime((time_t*)&j),stdout);
					}
				} else
				if ( get_filename ) puts(cur_block->hdr.name);
			} else
			if (print_location != 0) {
				printf(dds_loctext, tar_fb, tar_bs, cur_n);
			} else
			if ( print_blksize != 0 ) {
				printf("%d\n",tar_bs);
			} else {
				/*
				 * Print the current position (one line).
				 */
				printf(" -s %d -b %d \n", tar_fb, tar_bs);
			}
		}
		close(device);
		/*---------------------DDS2TAR-------------------------------*/
	} else if (pg == DDS2TAR) {

		if (pattern_list == NULL)
			return 0;
		if (list_only != 1) {
			device = open_device(device_name, O_RDONLY);

			if ( density ) dds_set_bs(density);
		}
		index_fp = zfopen(index_file, compressed_mode, "r");
		switch (mode) {
#ifdef EXP_STUFF
		case LOCATION:
			extract_loc(pattern_list);
			break;
#endif
		case EXTRACT:
			dds_cmp(pattern_list);
			break;
		default:
			fprintf(stderr, "nothing to do ? Try --help\n");
		}
		if (list_only != 1)
			close(device);
		if (child_proc != -1)
			cclose(1);
		/*---------------------DDS2INDEX-----------------------------*/
	} else if (pg == DDS2INDEX) {
		device = open_device(device_name, O_RDONLY);
		if ( density ) dds_set_bs(density);
		index_fp = zfopen(index_file, compressed_mode, "w");
		dds_index();
		close(device);
		/*-----------------------------------------------------------*/
	} else if ( pg == DDS_DD ) {
		device = open_device(device_name, O_RDONLY);
		if ( density ) dds_set_bs(density);
		if ( verbose ) fprintf(stderr,"dds-dd ...\n");
		while ( dds_read_next_block() , cur_n )
			fwrite(cur_block,1,cur_n,stdout);
	} else {
		fprintf(stderr, "no program mode \n");
		/*-----------------------------------------------------------*/
	}
	return 0;
}