#!/bin/bash
#.Y / 70 83 / / / / 105 / / / /	 / /	      ;A4_QUER.Y
#.YT 3 2 0 0 3 3 1 / / /
#.H!a!0:linux/<scripts>/io/tape_/ft!0.!c
#
# copyright : (C) 2009 by Thomas Bruecker =: tbrue
# email     : public0x05bf@bluewin.ch
#
# tbrue 12jun2006
#
# ft : tape functions of a floppy tape
#+++++++++++++++++++++++++++++++++++++
#
# $1 in {N, NRAW, R, RAW, SCRIPT}
#
# MyHash("linux/<scripts>/io/tape_/ft") = 0x0A29
#
# * for every function:
#   * if returned result is not commented, the function returns 0 on no-error.
#

# default device for ftformat:
# ---------------------------
#
# default device for ftformat is /dev/rawft0, so use raw device.
 
# default device for vtblc:
# ------------------------
#
# default device for vtblc is /dev/rawft0, so use raw device.
 

# functions:
# ---------


if [ "SCRIPT" = "$1" ]; then                       # is part of the tape-device-
                                                   # script.
    tape_asf()
      # $1: device, $2: count.
      # * count = 0 --> first file=volume.
      {
        ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 asf $2
        return
      }


    tape_badSectors()
      # $1: device.
      {
        vtblc --bsm -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
          return
      }


    tape_bs()
      # $1: device, $2 device-specifier in {N, NRAW, R, RAW}.
      {
        ftmt -f $(. $1 $2) \
	           setblk $BS_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
          return
      }


    tape_contents()
      # $1: device.
      {
        vtblc -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 --print
          return
      }


    tape_ddFrom()
      # $1: device, $2...: parameters.
      # * dd with input=device --> output from tape.
      # * no need to give count if reading file=volume; stops automatically.
      {
        local Device0x0A29 Result0x0A29

        Device0x0A29=$1
        shift 1

        tape_ddParameterError from $*
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi
           # else	    

        tape_bs $Device0x0A29 N
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi
            # else
	    
        dd  if=$DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
          bs=$BS_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 $*
        return
      }


    tape_ddTo()
      # $1: device, $2...: parameters.
      # * dd with output=device --> output to tape.
      # * with DeviceN, every dd_of=<tape>_operation creates a new file=volume.
      # * you are not allowed to append to an existing volume.
      # * if the file-position is at a not-emtpy-volume, the dd-operation is
      #   not allowed, except at volume 0; this is overwritten and the follo-
      #   wing volumes are deleted.
      {
        local Device0x0A29 Result0x0A29

        Device0x0A29=$1
        shift 1

        tape_ddParameterError to $*
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi
            # else	    

        tape_bs $Device0x0A29 N
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi
            # else
	    
        dd  of=$DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
          bs=$BS_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 $*
          return

        # do not rewind tape, allow tape_ddTo to append to the existing
        # files=volumes.
      }

    tape_delete()
      # $1: device.
      # * delete last file=volume .
      { 
        vtblc -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 -t
          return
      }


    tape_emptyQ()
      # $1: device.
      # * print
      #   0 to stdout if tape is empty,
      #   1 to stdout else.
      {
        local Result0x0A29 vtbl0x0A29
	
        Result0x0A29=$(tape_validHeaderQ $1)
          if [ $Result0x0A29 = "1" ]; then
              echo 0                               # invalid header ==> tape is
              return                               # empty.
            fi
            # else
            
        vtbl0x0A29=$(vtblc \
                     -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
                     --print)
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi
	    
        # strip leading comments / title:	    
          vtbl0x0A29=$(echo "$vtbl0x0A29" | tail +7 -)
	  
        if [ -z "$vtbl0x0A29" ]; then  echo 0
          else  echo 1
          fi

	      return 0
      }


    tape_eom()
      # $1: device.
      # * advance to the end of recorded area, ready to append another
      #   file=volume.
      {
        ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 eom
          return
      }


    tape_erase()
      # $1: device.
      {
        ftmt -f $DeviceR_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 erase
          return
      }


    tape_flf()
      # $1: device.
      # * advance to the begin of the last recorded file=volume. ready to read
      #   it.
      {
        local Result0x0A29
	
        ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 eom
          Result0x0A29=$?
          if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi

        ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 bsf 2
          return
      }

    tape_format120()
      # $1: device.
      #
      {
        local QDiscardHeader0x0A29                 # ?DiscardHeader

        . /etc/tape/qic80/120MB                    # get format-parameters.

        # avoid error with invalid header when trying to read the old header-
        # segment:
          echo "    check '$1' for a valid header."
            if [ $(tape_validHeaderQ $1) = "0" ]; then
                QDiscardHeader0x0A29=""            # valid header: keep it.
              else
                QDiscardHeader0x0A29="--discard-header"
                                                   # invalid header: discard it.
              fi

        # * what is intended:
        #   * keep the old bad-sector-map, so do not use the option
        #                                                   "--discard-header" .
        # * --- but: ftformat (ftape-tools) ver. 1.09 stops after formatting
        #   and before verifying, returning the error-code 255 and the error-
        #   message "Error re-opening tape dev read/write: Device or resource
        #                           busy"; so the old header is lost anyway. 1*)
        # * to avoid the error-message "Tape drive error sending physical for-
        #   ward command: 15 (Command Illegal or Undefined in Format Mode)", use
        #   the option "--omit-erase" .
        #
          ftformat -f $DeviceRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
                   $format_parameters_CB5853FF_382E_11DA_BABF_0000C00A45A9 \
                   --mode=force --omit-erase $QDiscardHeader0x0A29
                   # test stuff:
                     # --no-reference-bursts
            return
      }


    tape_getBS()
      # $1: device.
      # * print block-size to stdout.
      {
        echo "$BS_0xCB5853FF_382E_11DA_BABF_0000C00A45A9"
          return
      }


    tape_retension()
      # $1: device.
      {
        ftmt -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 retension
          return
      }


    tape_rewind()
      # $1: device, $2 device-specifier in {N, NRAW, R, RAW}.
      {
        ftmt -f $(. $1 $2) rewind
          return
      }

    tape_size()
      # $1: device.
      {
        local RealSize0x0A29 Result0x0A29 Size0x0A29 VolInfo0x0A29
	
        # must not use raw device here !
          VolInfo0x0A29=$(ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
                          --long-numbers volinfo)
            Result0x0A29=$?
            if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi

        # get real size:
          # chose correct line:
            # delete unwanted columns:
              # remove leading spaces:	
          RealSize0x0A29=$(echo "$VolInfo0x0A29" \
            | grep "real size of volume" \
              |  colrm 34 | colrm 1 22 \
                | sed 's/ *//')

        # get size:
          # chose correct line:
            # delete unwanted columns:
              # remove leading spaces:	
          Size0x0A29=$(echo "$VolInfo0x0A29" \
            | grep "physical space used" \
              |  colrm 34 | colrm 1 22 \
                | sed 's/ *//')
                
        # * let "l" be the nr. of the last file=volume in the volume-table.
        # * you may move to "a succeding file=volume" ( with nr. "l + 1" )
        #   of file=volume nr. "l" eg. with tape_asf ... <l + 1> or tape_eom .
        # * this file=volume nr. "l + 1" has a "Size" of the free tape space;
        #   but actually it is emtpy, so its size should be 0 ...
        # * the "RealSize" of this file=volume nr. "l + 1" is an empty string.
        # * so adjust the "Size" according to the "RealSize" :
          if [ -z "$RealSize0x0A29" ]; then
              Size0x0A29=0
            fi
	      
        let "Size0x0A29 = Size0x0A29 * 1024"       # blocks > bytes . 
        echo "$Size0x0A29" 

      }


    tape_space()
      # $1 in { b,... } : unit, $2: device.
      {
        local Result0x0A29 Space0x0A29
	
        # must not use raw device here !
          Space0x0A29=$(ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
                        --long-numbers getsize)
            Result0x0A29=$?
            if [ ! "$Result0x0A29" = "0" ]; then  return $Result0x0A29;  fi

        # chose correct line:
          # delete unwanted columns:
            # remove leading spaces:	
        Space0x0A29=$(echo "$Space0x0A29" \
          | grep "total bytes left" \
            |  colrm 34 | colrm 1 22 \
              | sed 's/ *//')

        # format according to unit:   
          case "$1" in
              b)
                  let "Space0x0A29 = $Space0x0A29 * 1024"
	        ;;
              K)
                  # in 1024 byte units; it's already ok.
	        ;;
              kB)
                  # in 1000 byte units; we want to grant enough space, so round
		  # 999 bytes down to 0 kB :
                    let "Space0x0A29 = $Space0x0A29 * 1024 / 1000"
	        ;;
              M)
                  # in 1024 * 1024 byte units; we want to grant enough space,
		  # so round (1024 * 1024 - 1) bytes down to 0 M :
                    let "Space0x0A29 = $Space0x0A29 / 1024"
	        ;;
              MB)
                  # in 1,000,000 byte units; we want to grant enough space,
		  # so round (1,000,000 - 1) bytes down to 0 MB :
                    let "Space0x0A29 = $Space0x0A29 * 1024 / 1000000"
	        ;;
              *)
	          echo $"Usage: $0 --> tape_SPACE {???????}"
	          return 1
            esac
	
        echo $Space0x0A29
          return
      }

      
    tape_statistics()
      # $1: device.
      {
        cat /proc/ftape
          return
      }


    tape_status()
      # $1: device.
      {
        ftmt -f $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 status
          return
      }


    tape_validHeaderQ()                            # validHeader?
      # $1: device.
      # * print
      #   0 to stdout if tape contains a valid header,
      #   1 to stdout else.
      {
        tape_badSectors $Device0x0A29 N  > /dev/null 2>&1
          # just simple: ...badSectors returns 0 if a valid header exists,
          # 1 if it is not able to read the header.
          if [ $? = "0" ]; then
              echo 0
            else
              echo 1
            fi
        return
      }


    tape_verify()
      # $1: device.
      #
      # * statistics do not correlate with bad sectors, so do not save it.
      # * according to tape_format120 1*), the old header is discarded anyway.
      #
      {
        local QDiscardHeader0x0A29                 # ?DiscardHeader

        . /etc/tape/qic80/120MBV

        # avoid error with invalid header when trying to read the old header-
        # segment:
          echo "    check '$1' for a valid header."
            if [ $(tape_validHeaderQ $1) = "0" ]; then
                QDiscardHeader0x0A29=""            # valid header: keep it.
              else
                QDiscardHeader0x0A29="--discard-header"
                                                   # invalid header: discard it.
              fi

        ftformat -f $DeviceRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
                 $verify_parameters_CB5853FF_382E_11DA_BABF_0000C00A45A9 \
                 --mode=force --verify-only $QDiscardHeader0x0A29

# old: 	         --verify-only=erase-bad-sector-map \
# test:
#	         --verify-only=dont-write-header-segments --print-header > logXXX
#     	         --verify-only
          return
      }

    tape_vtblModify()
      # $1: device, $2: name, $3, $4: date.
      # * modify the last entry of the volume-table.
      #   * if $3... are not specified, modify to current date.
      {
        local Device0x0A29 Name0x0A29 NumArguments0x0A29

        Device0x0A29=$1; Name0x0A29=$2; NumArguments0x0A29=$#
        shift 2
	
        if [ "$NumArguments0x0A29" = "2" ]; then
            vtblc -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
	          --modify=label=$Name0x0A29 --modify=date
              return
          else
            vtblc -f $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9 \
	          --modify=label=$Name0x0A29 --modify=date="$*"
              return
          fi	         
      }

  fi                                               # end of script

# parameter handling:
# ------------------

  case "$1" in
      N)
          echo $DeviceN_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
        ;;
      NRAW)
          echo $DeviceNRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
        ;;
      R)
          echo $DeviceR_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
        ;;
      RAW)
          echo $DeviceRAW_0xCB5853FF_382E_11DA_BABF_0000C00A45A9
        ;;
      SCRIPT)
        ;;
      *)
          echo "Usage: $0 {N| NRAW| R| RAW| SCRIPT}" 
          echo "  N:      print non-rewinding device-name."
          echo "  NRAW:   print non-rewinding raw device-name."
          echo "  R:      print rewinding device-name."
          echo "  RAW:    print rewinding raw device-name."
          echo "  SCRIPT: invoke it as script."
          exit 1
    esac