#!/bin/bash
#.Y / 70 83 / / / / 105 / / / /	 / /	      ;A4_QUER.Y
#.YT 3 2 0 0 3 3 1 / / /
#.H!a!0:linux/<scripts>/io/tape_/THIS!0.!c
#
# copyright : (C) 2009 by Thomas Bruecker =: tbrue
# email     : public0x05bf@bluewin.ch
#
# tbrue 12jun2006
#
# tape_ THIS : tape functions
#++++++++++++++++++++++++++++
#
# called without any parameters.
#
# MyHash("linux/<scripts>/io/tape_/THIS") = 0x0A87
#
# * for every function:
#   * if returned result is not commented, the function returns 0 on no-error.
#
# * pendent:
#   * tape_vtblModify actually ok, but problems if name with spaces???

SCRIPTS=root/bin

. /$SCRIPTS/io/f_/THIS
. /$SCRIPTS/math/THIS

tape_DeviceOk()
  # $1: device
  # * returns 0 if device is ok.
  {
    local Message0x0A87

    if [ -x $(f_ToFinalTarget $1) ]; then          # device is an executable
                                                   # file.
        # if magic-number is ok:
          # get line# 5:          #
            # get first 5 lines:
              # get last line of 5 lines:
                # match magic-number: 
          if                 \
    	        head -5 $1 |   \
	              tail -1l - | \
                  grep -q "0xCB5853FF-382E-11DA-BABF-0000C00A45A9"; then
	            return                               # device is ok; grep returns 0 on 
            else                                   # a match.
	      Message0x0A87="invalid magic-number in '$1'."
	    fi

      else	      
        Message0x0A87="file-type of '$1' is invalid."
      fi	  	    
          # else	
      # else	
        echo "$0 --> tape_DeviceOk: '$1' is not a character special file:" >&2
	echo "    $Message0x0A87" >&2
	return 1
  }


tape_ASF()
  # $1: device, $2: count
  # * count = 0 --> first file=volume.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_asf $1 $2                             # do it.
    return
  }


tape_BadSectors()
  # $1: device
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_badSectors $1                         # do it.
    return
  }

tape_BS()
  # $1: device, $2: device-specifier in {N, NRAW, R, RAW} .
  # * set block-size.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_bs $1 $2                              # do it.
    return
  }


tape_CONTENTS()
  # $1: device.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_contents $1                           # do it.
    return
  }


tape_DDFrom()
  # $1: device, $2...: parameters
  # * dd with input=device --> output from tape.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_ddFrom $1 $*                          # do it.
    return
  }


tape_ddParameterError()
      # $1: in {from, to}; from: fixed if, to: fixed of; $*: parameters.
      {
        local Selector0x0A87

        Selector0x0A87=$1
        shift 1

        # parameter must not contain "bs=":
	        echo $* | grep -q "bs="
            if [ "$?" = "0" ]; then                # some matching.
	              echo "$0 --> tape_ddParameterError: parameters should not\
 contain \"bs=\"." 
	              return 1
              fi
              # else
	    	      
        # reject according to "from", "to":   
          case "$Selector0x0A87" in
              from)
                  # parameter must not contain "if=":
	                  echo $* | grep -q "if="
                      if [ "$?" = "0" ]; then      # some matching.
	                        echo "$0 --> tape_ddParameterError: parameters should\
 not contain \"if=\"." 
	                        return 1
                        fi
	                      # else
                  # parameter must not contain "skip=":
	                  echo $* | grep -q "skip="
                      if [ "$?" = "0" ]; then      # some matching.
	                        echo "$0 --> tape_ddParameterError: parameters should\
 not contain \"skip=\"." 
	                        return 1
                        fi
        	              # else
	              ;;
              to)
                  # parameter must not contain "of=":
	                  echo $* | grep -q "of="
                      if [ "$?" = "0" ]; then      # some matching.
	                        echo "$0 --> tape_ddParameterError: parameters should\
 not contain \"of=\"." 
	                        return 1
                        fi
	                      # else
                  # parameter must not contain "seek=":
	                  echo $* | grep -q "seek="
                      if [ "$?" = "0" ]; then      # some matching.
	                        echo "$0 --> tape_ddParameterError: parameters should\
 not contain \"seek=\"." 
	                        return 1
                        fi
	                      # else
	              ;;
            esac
      }


tape_DDTo()
  # $1: device, $2...: parameters
  # * dd with output=device --> output to tape.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_ddTo $1 $*                            # do it.
    return
  }


tape_DELETE()
  # $1: device.
  # * delete last file=volume .
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_delete $1                             # do it.
    return
  }


tape_EmptyQ()                                      # Empty?
  # $1: device
  # * print
  #   0 to stdout if tape is empty.
  #   1 to stdout else.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_emptyQ $1                             # do it.
    return
  }

tape_EOM()
  # $1: device.
  # * advance to the end of recorded area, ready to append another
  #   file=volume.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_eom $1                                # do it.
    return
  }


tape_ERASE()
  # $1: device.
  {
    local Answer0x0A87
    
    echo -e "\nERASING THE TAPE :"
    echo    "  ALL DATA ON THE TAPE WILL BE DESTROYED !!!"
    echo    "  DO YOU REALLY WANT TO ERASE THE TAPE ?"
    echo    "  type \"yes\" to confirm erasing."

    read Answer0x0A87
    if [ "$Answer0x0A87" != "yes" ]; then   return;  fi
      # else
    
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.

        echo    "'$1' is beeing erased now."
          tape_erase $1
	    return
  }


tape_FLF()
  # $1: device.
  # * advance to the begin of the last recorded file=volume. ready to read it.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_flf $1                                # do it.
    return
  }


tape_FORMAT120()
  # $1: device
  {
    local EmptyQ0x0A87 I0x0A87 Result0x0A87
    
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else

    . $1 SCRIPT                                    # get device-script.
	
    echo "  check if '$1' is empty."
      EmptyQ0x0A87=$(tape_EmptyQ $1);
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    if [ $EmptyQ0x0A87 != "0" ]; then
        echo "$0 --> tape_FORMAT: strictly refusing to format a not-empty\
 tape !!!"         >&2
        return 1
      fi
      # else
	
    echo "  retension '$1'."
      for (( I0x0A87 = 0; 5 > I0x08A7; I0x08A7++ ))
          do
            echo -n " $I0x08A7"  
            tape_retension $1
        done    

    echo "  rewind '$1'."
      tape_rewind $1 NRAW
    echo "  format '$1'."
      tape_format120 $1
    return
  }


tape_GetBS()
  # $1: device.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_getBS $1                              # do it.
    return
  }


tape_QKDatVolume()                                 #?KDatVolume
  # $1: device
  # * if tape is emtpy and if not already present, write the KDat file=volume
  #   to the tape.
  {
    local EmptyQ0x0A87 Result0x0A87
    # no need to test by "tape_DeviceOk", tested later by "tape_Empty?" .
    
    . $1 SCRIPT                                    # get device-script.
    
    EmptyQ0x0A87=$(tape_EmptyQ $1);
      Result0x0A87=$?
      if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
        # else

    if [ "$EmptyQ0x0A87" = "0" ]; then
        tape_asf $1 0
          Result0x0A87=$?
          if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
            # else

        echo "  write kDatVolume."
          tape_ddTo $1 if=/etc/tape/kdat.id
            Result0x0A87=$?
            if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
              # else

        tape_rewind $1 N
          Result0x0A87=$?
          if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
            # else
	    
        tape_vtblModify $1 KDatId                  # use current date.
        return

      fi
      # else
        return 0
  }

tape_MD5BlockSums()
  {
    echo $1 | mathMD5BlockSums
  }

  
tape_md5sum()
  # $1: device.
  # * sum over current file=volume, print sum to stdout.
  {
    tape_ddFrom $1 | md5sum -b
      return
  }


tape_MD5SUM()
  # $1: device.
  # * sum over current file=volume, print sum to stdout.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_md5sum $1
 	  return
  }


tape_RETENSION()
  # $1: device
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_retension $1                          # do it.
    return
  }


tape_REWIND()
  # $1: device, $2: device-specifier in {N, NRAW, R, RAW} .
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_rewind $1 $2                          # do it.
    return
  }


tape_SIZE()
  # print size of current file=volume to stdout.
  # $1 in { b,... } : unit, $2: device.
  {
    local Result0x0A87 Size0x0A87
    if ! tape_DeviceOk $2; then
        return 1                                   # error message is done by 
      fi                                           # tape_DeviceOk .
      # else
      
    . $2 SCRIPT                                    # get device-script.
    Size0x0A87=$(tape_size $2)
      Result0x0A87=$?
      if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
        # else

    # if we are copying the current file=volume to somewhere, we want to grant
    # enough space on somewhere, so we round up --> "U" .
      mathToUnit $1 U $Size0x0A87
        if [ $? -eq 2 ]; then                      # invalid unit.
            math_toUnitError "$0 --> tape_SIZE " "" TAPE-DEVICE
            return 1
          fi
          # else

    return 0
  }


tape_SPACE()
  # print free space on tape to stdout.
  # $1 in { b,... } : unit, $2: device.
  {
    if ! tape_DeviceOk $2; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $2 SCRIPT                                # get device-script.
        tape_space $1 $2                           # do it.
    return
  }


tape_SpaceQ()                                      # Space?
  # $1: source-file,  $2: destination-tape-device.
  # * print
  #   0 to stdout if there is enough space for source-file on tape.
  #   1 to stdout else.
  {
    local Result0x0A87 TapeSpace0x0A87 SizeOfSource0x0A87
    
    # no need to test by "tape_DeviceOk", tested later by "tape_SPACE" .
    
    . $2 SCRIPT                                    # get device-script.

    SizeOfSource0x0A87=$(f_SIZE b $1)
      Result0x0A87=$?
      if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
        # else

    TapeSpace0x0A87=$(tape_SPACE b $2)
      Result0x0A87=$?
      if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
        # else
	
    if ! [ $TapeSpace0x0A87 -lt $SizeOfSource0x0A87 ]; then  echo 0
      else  echo 1
      fi
      
    return 0
  }


tape_STATISTICS()
  # $1: device
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_statistics $1                         # do it.
    return
  }


tape_STATUS()
  # $1: device.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_status $1                             # do it.
    return
  }


tape_ToTHIS()
  # $1: source-file,  $2: destination-tape-device.
  # * copy source-file to new tape file=volume at the end of the tape.
  # * if source-file is a link,
  #   * the name of the file=volume on the tape is the name of the link.
  #   * the date and time of the file=volume on the tape is the date of the
  #     actual file, pointed at by the link.
  {
    local Result0x0A87 SpaceQ0x0A87 TmpFile0x0A87
    
    if ! tape_DeviceOk $2; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else

    . $2 SCRIPT                                    # get device-script.

    if [ ! -d /mnt/tmpfs ]; then
        echo "$0 --> tape_ToThis: \"/mnt/tmpfs\" does not exist."
        return 1
      fi
      # else

    echo -e "  retension '$2'."
      tape_retension $2		                         # we should do it, the sour-
        Result0x0A87=$?                            # ce-file may be large.
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    # must be checked before space-checking, because the kDat-volume needs some
    # space too.
      echo -e "  check for kDat-volume on '$2'."
        tape_QKDatVolume $2		     
          Result0x0A87=$?
          if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
            # else

    echo -e "  check for enough space on '$2'."
      SpaceQ0x0A87=$(tape_SpaceQ $1 $2);           # Space?0x0A87
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

        if [ $SpaceQ0x0A87 != "0" ]; then
            echo "$0 --> tape_ToThis: not enough space on '$2'." >&2
            return 1
          fi
          # else

    TmpFile0x0A87=$(mktemp /mnt/tmpfs/$1.XXXXXX)
      Result0x0A87=$?
      if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
        # else

    echo -e "\n  copy '$1' to '/mnt/tmpfs'."
      dd if=$1 of=$TmpFile0x0A87 bs=$(tape_getBS $2)
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    echo -e "\n  copy from '/mnt/tmpfs' to '$2'."
    
      tape_eom $2                             # move to free area.
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

      tape_ddTo $2 if=$TmpFile0x0A87
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

      tape_statistics $2 > $1.wstat

      tape_rewind $2 N
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

      rm -f $TmpFile0x0A87
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    echo -e "\n  adjust volume-table-entry."
      tape_vtblModify $2 $(f_PathToName $1) \
                      $( f_TimeTD $(f_ToFinalTarget $1) )
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    # calculate md5-sum.
      echo -e "\n    retension '$2'."
        tape_retension $2
          Result0x0A87=$?
          if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
            # else

      echo -e "  calculate md5-sum."

      tape_flf $2
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else
	    
      tape_md5sum $2 > $1.md5
        Result0x0A87=$?

      tape_statistics $2 > $1.rstat
      return $Result0x0A87
  }


tape_VERIFY()
  # $1: device
  {
    local EmptyQ0x0A87 Result0x0A87
    
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi	                                         # tape_DeviceOk .
      # else
      
    . $1 SCRIPT                                    # get device-script.
	
    echo "  check if '$1' is empty."
      EmptyQ0x0A87=$(tape_EmptyQ $1);
        Result0x0A87=$?
        if [ ! "$Result0x0A87" = "0" ]; then  return $Result0x0A87;  fi
          # else

    if [ $EmptyQ0x0A87 != "0" ]; then
        echo "$0 --> tape_VERIFY: strictly refusing to verify a not-empty\
 tape !!!"         >&2
        return 1
      fi
      # else
		    
    echo "  retension '$1'."
      tape_retension $1
    echo "  rewind '$1'."
      tape_rewind $1 NRAW
    echo "  verify '$1'."
      tape_verify $1
    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.
  {
    if ! tape_DeviceOk $1; then
        return 1                                   # error message is done by 
      fi                                           # tape_DeviceOk .
      # else
        . $1 SCRIPT                                # get device-script.
        tape_vtblModify $*                         # do it.
    return
  }