This commit is contained in:
Patrick J Cherry
2018-02-02 21:34:14 +00:00
parent 1b7b688f7a
commit 9c48da82cc
40 changed files with 666 additions and 858 deletions

View File

@@ -3,13 +3,13 @@
#
class FileWriter
def initialize(filename, blocksize)
@fh = File.open(filename, "w+")
@fh = File.open(filename, 'w+')
@blocksize = blocksize
@pattern = ""
@pattern = ''
end
def size
@blocksize * @pattern.split("").size
@blocksize * @pattern.split('').size
end
# We write in fixed block sizes, given by "blocksize"
@@ -20,8 +20,8 @@ class FileWriter
def write(data)
@pattern += data
data.split("").each do |code|
if code == "_"
data.split('').each do |code|
if code == '_'
@fh.seek(@blocksize, IO::SEEK_CUR)
else
@fh.write(data(code))
@@ -31,15 +31,14 @@ class FileWriter
self
end
# Returns what the data ought to be at the given offset and length
#
def read_original( off, len )
patterns = @pattern.split( "" )
patterns.zip( (0...patterns.length).to_a ).
map { |blk, blk_off|
def read_original(off, len)
patterns = @pattern.split('')
patterns.zip((0...patterns.length).to_a)
.map do |blk, blk_off|
data(blk, blk_off)
}.join[off...(off+len)]
end.join[off...(off + len)]
end
# Read what's actually in the file
@@ -60,68 +59,66 @@ class FileWriter
protected
def data(code, at=@fh.tell)
def data(code, at = @fh.tell)
case code
when "0", "_"
"\0" * @blocksize
when "X"
"X" * @blocksize
when "f"
r = ""
(@blocksize/4).times do
r += [at].pack("I")
at += 4
end
r
else
raise "Unknown character '#{block}'"
when '0', '_'
"\0" * @blocksize
when 'X'
'X' * @blocksize
when 'f'
r = ''
(@blocksize / 4).times do
r += [at].pack('I')
at += 4
end
r
else
raise "Unknown character '#{block}'"
end
end
end
if __FILE__==$0
if $PROGRAM_NAME == __FILE__
require 'tempfile'
require 'test/unit'
class FileWriterTest < Test::Unit::TestCase
def test_read_original_zeros
Tempfile.open("test_read_original_zeros") do |tempfile|
Tempfile.open('test_read_original_zeros') do |tempfile|
tempfile.close
file = FileWriter.new( tempfile.path, 4096 )
file.write( "0" )
assert_equal file.read( 0, 4096 ), file.read_original( 0, 4096 )
assert( file.untouched?(0,4096) , "Untouched file was touched." )
file = FileWriter.new(tempfile.path, 4096)
file.write('0')
assert_equal file.read(0, 4096), file.read_original(0, 4096)
assert(file.untouched?(0, 4096), 'Untouched file was touched.')
end
end
def test_read_original_offsets
Tempfile.open("test_read_original_offsets") do |tempfile|
Tempfile.open('test_read_original_offsets') do |tempfile|
tempfile.close
file = FileWriter.new( tempfile.path, 4096 )
file.write( "f" )
assert_equal file.read( 0, 4096 ), file.read_original( 0, 4096 )
assert( file.untouched?(0,4096) , "Untouched file was touched." )
file = FileWriter.new(tempfile.path, 4096)
file.write('f')
assert_equal file.read(0, 4096), file.read_original(0, 4096)
assert(file.untouched?(0, 4096), 'Untouched file was touched.')
end
end
def test_file_size
Tempfile.open("test_file_size") do |tempfile|
Tempfile.open('test_file_size') do |tempfile|
tempfile.close
file = FileWriter.new( tempfile.path, 4096 )
file.write( "f" )
assert_equal 4096, File.stat( tempfile.path ).size
file = FileWriter.new(tempfile.path, 4096)
file.write('f')
assert_equal 4096, File.stat(tempfile.path).size
end
end
def test_read_original_size
Tempfile.open("test_read_original_offsets") do |tempfile|
Tempfile.open('test_read_original_offsets') do |tempfile|
tempfile.close
file = FileWriter.new( tempfile.path, 4)
file.write( "f"*4 )
file = FileWriter.new(tempfile.path, 4)
file.write('f' * 4)
assert_equal 4, file.read_original(0, 4).length
end
end
end
end