/* 
 * MADER Project    N.O.A.A.  - FSL/NCDC
 *
 * This software and its documentation are in the public domain
 * and are furnished "as is."  The United States government,
 * its instrumentalities, officers, employees, and agents make
 * no warranty, express or implied, as to the usefulness of the
 * software and documentation for any purpose.  They assume no
 * responsibility (1) for the use of the software and
 * documentation; or (2) to provide technical support to users.
 * 
 */
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mtio.h>

#define BUFF 20000
#define PERMS 0666  /* RW for owner, group, others */
#define ERR -1
#define FLEN 10
#define OUT 50
#define OFF 270
long int lseek();

/*-----------------------------------------------------------------------------
 * Name:   wrebufr.c
 *
 * Author: Dan Manns
 *
 * Purpose: write the EBUFR data files to disk as they exist on tape
 *          (these files are not readable by EBUFR software because of
 *          the leading 4 character record length field)
 *
 * Parameters: nskip - This parameter indicates how many days of data the 
 *    user wants to skip before writing to disk. If the tape was created at
 *    NCDC then it is probably unlabeled. If the tape is labeled obviously
 *    either the script or the this program must be altered to skip the 
 *    appropriate number of files.
 *
 * Return values: 
 *    0 -- successful 
 *    not 0 -- some error causing archive termination
 *
 * Dependencies: The user needs to change this software to access the proper
 *    tape drive id.
 *
 * Modifications: none
 *-----------------------------------------------------------------------------
 */
main( argc, argv )
int argc;
char **argv;
{

     int     fdisk, ftape, n, totrd, rd, nfile, eofct;
     int     sector, nskip, flog;
     char    fname[FLEN];
     char    buf[BUFF];
     char    orec[OUT];
     struct mtop mt_command;

/* the user must change the tape drive id */
     rd = 0;
     if ((ftape = open("/dev/rst1",0)) == ERR)
            {
              printf("Can't open /dev/rst1 %d\n",ERR); 
              exit(ERR);
            }
              
/* the user must change the tape drive id */
     printf("\n  opened /dev/rst1 \n");
     mt_command.mt_op = MTREW;
     mt_command.mt_count = 1;
     ioctl(ftape,MTIOCTOP,&mt_command);

     if ((flog = open("arc.log",O_RDONLY,0)) == ERR)
     {
         printf("Can't open arc.log\n");
         exit(ERR);
     }
/*
 * read the number of files to skip
 */
     nskip=atoi(argv[1]);
     if( nskip != 0 )
       {
               mt_command.mt_op = MTFSF;
               mt_command.mt_count = nskip;
               ioctl(ftape,MTIOCTOP,&mt_command);           
       }
     /* 
      * Continue processing as long as filenames are read from arc.log
      */
     nfile = 0;
     while ((n = read(flog, fname, FLEN)) > 0)
     {
         fname[9]='\0';

/* Read the data files and write them to disk .            */
         nfile = 0;
         eofct = 0;
         if ((fdisk = creat(fname,PERMS )) == ERR)
             printf("Can't open %s\n",fname);
         else
         {             
            printf("  created %s \n",fname);
            while (eofct < 1)
            {
               mt_command.mt_op = MTFSF;
               mt_command.mt_count = 1;
               ioctl(ftape,MTIOCTOP,&mt_command);           

               while ((n = read(ftape, buf, BUFF)) > 0)
               {  
                   ++rd;

                   if (nfile < 1)
                   {
                       if (write(fdisk, buf, n) != n)
                       {
                           printf("Write error on %s\n",fname);
                           exit(ERR);
                       }
                   }

               }

               totrd = totrd + rd;

               printf(" found EOF mark \n");
               rd = 0;
               ++eofct;

            }
            printf("      finished writing to %s\n",fname);
            mt_command.mt_op = MTFSF;
            mt_command.mt_count = 1;
            ioctl(ftape,MTIOCTOP,&mt_command);           
         }

         close(fdisk);
     }       

     return;
}