require 'fs/iso9660/util'
require 'binary_struct'
require 'util/miq-unicode'
module Iso9660
class BootSector
# Universal Volume Descriptor ID.
DESCRIPTOR_ID = "CD001"
# Volume descriptor types.
TYPE_BOOT = 0 # The descriptor is a boot record.
TYPE_PRIM_DESC = 1 # The descriptor is a primary volume descriptor.
TYPE_SUPP_DESC = 2 # The descriptor is a supplementary volume descriptor.
TYPE_PART_DESC = 3 # The descriptor is a volume partition descriptor.
TYPE_TERMINATOR = 255 # Marks the end of descriptor records.
# NOTE: the spec says terminator is 4, but it seems to be 255.
# This serves as both the primary and supplementary descriptor structure.
VOLUME_DESCRIPTOR = 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
attr_reader :sectorSize, :descType, :fsId, :volName
attr_reader :cTime, :mTime, :expirationDate, :effectiveDate
attr_reader :rootEntry, :recId, :suff
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
def diskSize
@bs["vol_space_size#{@suff}"] * @sectorSize
end
def getSectors(sector, num = 1)
@stream.seek(sector * @sectorSize)
@stream.read(@sectorSize * num)
end
def isJoliet?
@isJoliet
end
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
# This is a raw dump with no character set conversion.
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
end # class
end # module