Class: Iso9660::BootSector

Inherits:
Object
  • Object
show all
Defined in:
lib/fs/iso9660/boot_sector.rb

Constant Summary collapse

DESCRIPTOR_ID =

Universal Volume Descriptor ID.

"CD001"
TYPE_BOOT =

Volume descriptor types.

0
TYPE_PRIM_DESC =

The descriptor is a boot record.

1
TYPE_SUPP_DESC =

The descriptor is a primary volume descriptor.

2
TYPE_PART_DESC =

The descriptor is a supplementary volume descriptor.

3
TYPE_TERMINATOR =

The descriptor is a volume partition descriptor.

255
VOLUME_DESCRIPTOR =

This serves as both the primary and supplementary descriptor structure.

BinaryStruct.new([
  'C',    'desc_type',                # TYPE_ enum.
  'a5',   'id',                       # Always "CD001".
  'C',    'version',                  # Must be 1.
  'C',    'vol_flags',                # Unused on primary.
  'a32',  'system_id',                # An 'extra' label.
  'a32',  'volume_id',                # Usually known as label.
  'a8',   'unused2',
  'L',    'vol_space_sizeLE',         # Size in sectors.
  'L',    'vol_space_sizeBE',
  'a32',  'esc_sequences',            # Unused on primary, Joliet CDs do not always record escape sequences (assume UCS-2L3).
  'S',    'vol_set_sizeLE',
  'S',    'vol_set_sizeBE',
  'S',    'vol_seq_numberLE',
  'S',    'vol_seq_numberBE',
  'S',    'log_block_sizeLE',         # Sector size in bytes (so far, alwyas 2048).
  'S',    'log_block_sizeBE',
  'L',    'path_table_sizeLE',        # This implementation ignores the path tables.
  'L',    'path_table_sizeBE',
  'S',    'type_1_path_tableLE',
  'S',    'type_1_path_tableBE',
  'S',    'opt_type_1_path_tableLE',
  'S',    'opt_type_1_path_tableBE',
  'S',    'type_m_path_tableLE',
  'S',    'type_m_path_tableBE',
  'S',    'opt_type_m_path_tableLE',
  'S',    'opt_type_m_path_tableBE',
  'a34',  'root_dir_record',          # DirectoryEntry representing root dir.
  'a128', 'vol_set_id',
  'a128', 'publisher_id',
  'a128', 'preparer_id',
  'a128', 'application_id',
  'a37',  'copyright_file_id',
  'a37',  'abstract_file_id',
  'a37',  'biblographic_file_id',
  'a17',  'creation_date',            # Dates are in ISO long date format.
  'a17',  'modification_date',
  'a17',  'experation_date',
  'a17',  'effective_date',
  'C',    'file_structure_version',   # Must be 1.
  'C',    'unused4',
  'a512', 'application_data',
  'a653', 'unused5'
])
SIZEOF_VOLUME_DESCRIPTOR = 
VOLUME_DESCRIPTOR.size

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(stream, joliet = false) ⇒ BootSector

Returns a new instance of BootSector.



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# File 'lib/fs/iso9660/boot_sector.rb', line 72

def initialize(stream, joliet = false)
  raise "Nil stream" if stream.nil?
  @stream = stream
  @isJoliet = joliet
  @jolietVerified = false

  # Get the suffix to use for all members.
  @suff = getSuffix

  # Read & check descriptor.
  @bs = VOLUME_DESCRIPTOR.decode(@stream.read(SIZEOF_VOLUME_DESCRIPTOR))
  @descType = @bs['desc_type']
  raise "Descriptor type mismatch (type is #{@descType})" if @descType != (@isJoliet ? TYPE_SUPP_DESC : TYPE_PRIM_DESC)
  @recId = @bs['id']
  raise "Descriptor ID mismatch" if @recId != "CD001"
  raise "Descriptor version mismatch" if @bs['version'] != 1
  raise "File structure version mismatch" if @bs['file_structure_version'] != 1

  # If this is supposed to be Joliet then try to verify.
  if @isJoliet
    esc = @bs['esc_sequences'].strip
    if esc[0, 2] == '%/'
      level = esc[2, 1]
      @jolietVerified = true if level == '@' || level == 'C' || level == 'E'
    end
  end
  # From now on, assume Joliet if @isJoliet is true.
  # If verification fails it's up to Directory & DirectoryEntry to be careful.

  # Read fs params.
  @sectorSize = @bs["log_block_size#{@suff}"]
  @volName = @bs['volume_id']
  @volName.Ucs2ToAscii! if @isJoliet
  # fsId can come from Rock Ridge ext if present.
  # Don't forget there's a serial number too if RR isn't there.
  @cTime = Util.IsoToRubyDate(@bs['creation_date'])
  @mTime = Util.IsoToRubyDate(@bs['modification_date'])
  @expirationDate = Util.IsoToRubyDate(@bs['expiration_date'])
  @effectiveDate = Util.IsoToRubyDate(@bs['effective_date'])

  # Filesystem root.
  @rootEntry = @bs['root_dir_record']
end

Instance Attribute Details

#cTime ⇒ Object (readonly)

Returns the value of attribute cTime.



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# File 'lib/fs/iso9660/boot_sector.rb', line 69

def cTime
  @cTime
end

#descType ⇒ Object (readonly)

Returns the value of attribute descType.



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# File 'lib/fs/iso9660/boot_sector.rb', line 68

def descType
  @descType
end

#effectiveDate ⇒ Object (readonly)

Returns the value of attribute effectiveDate.



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# File 'lib/fs/iso9660/boot_sector.rb', line 69

def effectiveDate
  @effectiveDate
end

#expirationDate ⇒ Object (readonly)

Returns the value of attribute expirationDate.



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# File 'lib/fs/iso9660/boot_sector.rb', line 69

def expirationDate
  @expirationDate
end

#fsId ⇒ Object (readonly)

Returns the value of attribute fsId.



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# File 'lib/fs/iso9660/boot_sector.rb', line 68

def fsId
  @fsId
end

#mTime ⇒ Object (readonly)

Returns the value of attribute mTime.



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# File 'lib/fs/iso9660/boot_sector.rb', line 69

def mTime
  @mTime
end

#recId ⇒ Object (readonly)

Returns the value of attribute recId.



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# File 'lib/fs/iso9660/boot_sector.rb', line 70

def recId
  @recId
end

#rootEntry ⇒ Object (readonly)

Returns the value of attribute rootEntry.



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# File 'lib/fs/iso9660/boot_sector.rb', line 70

def rootEntry
  @rootEntry
end

#sectorSize ⇒ Object (readonly)

Returns the value of attribute sectorSize.



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# File 'lib/fs/iso9660/boot_sector.rb', line 68

def sectorSize
  @sectorSize
end

#suff ⇒ Object (readonly)

Returns the value of attribute suff.



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# File 'lib/fs/iso9660/boot_sector.rb', line 70

def suff
  @suff
end

#volName ⇒ Object (readonly)

Returns the value of attribute volName.



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# File 'lib/fs/iso9660/boot_sector.rb', line 68

def volName
  @volName
end

Instance Method Details

#diskSize ⇒ Object 



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# File 'lib/fs/iso9660/boot_sector.rb', line 116

def diskSize
  @bs["vol_space_size#{@suff}"] * @sectorSize
end

#dump ⇒ Object

This is a raw dump with no character set conversion.



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# File 'lib/fs/iso9660/boot_sector.rb', line 141

def dump
  out = "\n"
  out += "Type            : #{@bs['desc_type']}\n"
  out += "Record ID       : #{@bs['id']}\n"
  out += "Version         : #{@bs['version']}\n"
  out += "System ID       : #{@bs['system_id'].strip}\n"
  out += "Volume ID       : #{@volName}\n"
  out += "Vol space size  : #{@bs["vol_space_size#{@suff}"]} (sectors)\n"
  out += "Vol set size    : #{@bs["vol_set_size#{@suff}"]}\n"
  out += "Vol sequence num: #{@bs["vol_seq_number#{@suff}"]}\n"
  out += "Logical blk size: #{@bs["log_block_size#{@suff}"]} (sector size)\n"
  out += "Path table size : #{@bs["path_table_size#{@suff}"]}\n"
  out += "Type 1 path tbl : #{@bs["type_1_path_table#{@suff}"]}\n"
  out += "Opt type 1 pth  : #{@bs["opt_type_1_path_table#{@suff}"]}\n"
  out += "Type M path tbl : #{@bs["type_m_path_table#{@suff}"]}\n"
  out += "Opt type M pth  : #{@bs["opt_type_m_path_table#{@suff}"]}\n"
  out += "Vol set ID      : #{@bs['vol_set_id'].strip}\n"
  out += "Publisher ID    : #{@bs['publisher_id'].strip}\n"
  out += "Preparer ID     : #{@bs['preparer_id'].strip}\n"
  out += "Application ID  : #{@bs['application_id'].strip}\n"
  out += "Copyright       : #{@bs['copyright_file_id'].strip}\n"
  out += "Abstract        : #{@bs['abstract_file_id'].strip}\n"
  out += "Biblographic    : #{@bs['biblographic_file_id'].strip}\n"
  out += "Creation date   : #{@bs['creation_date'].strip} (#{@cTime}, tz = #{Util.GetTimezone(@bs['creation_date'])})\n"
  out += "Mod date        : #{@bs['modification_date'].strip} (#{@mTime}, tz = #{Util.GetTimezone(@bs['modification_date'])})\n"
  out += "Expiration date : #{@bs['experation_date'].strip} (#{@expirationDate}, tz = #{Util.GetTimezone(@bs['experation_date'])})\n"
  out += "Effective date  : #{@bs['effective_date'].strip} (#{@effectiveDate}, tz = #{Util.GetTimezone(@bs['effective_date'])})\n"
  out += "File strct ver  : #{@bs['file_structure_version']}\n"
  out += "Application data: #{@bs['application_data'].strip}\n"
end

#getSectors(sector, num = 1) ⇒ Object 



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# File 'lib/fs/iso9660/boot_sector.rb', line 120

def getSectors(sector, num = 1)
  @stream.seek(sector * @sectorSize)
  @stream.read(@sectorSize * num)
end

#getSuffix ⇒ Object 



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# File 'lib/fs/iso9660/boot_sector.rb', line 129

def getSuffix
  if Sys::Platform::ARCH == :x86
    @@suff = 'LE'
  else
    # Other architectures are bi-endian and must be determined at run time.
    p = [0xaa, 0x55].pack('N')
    u = p.unpack('L')
    @@suff = u == 0xaa55 ? 'BE' : 'LE'
  end
end

#isJoliet? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/fs/iso9660/boot_sector.rb', line 125

def isJoliet?
  @isJoliet
end