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Feature #4495 » patch.diff

Glass_saga (Masaki Matsushita), 03/11/2011 01:34 PM

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lib/pstore.rb
require "fileutils"
require "digest/md5"
require "zlib"
require "thread"
#
......
# Constant for relieving Ruby's garbage collector.
EMPTY_STRING = ""
EMPTY_MARSHAL_DATA = Marshal.dump({})
EMPTY_MARSHAL_CHECKSUM = Digest::MD5.digest(EMPTY_MARSHAL_DATA)
EMPTY_MARSHAL_CHECKSUM = Zlib.crc32(EMPTY_MARSHAL_DATA)
#
# Open the specified filename (either in read-only mode or in
......
size = empty_marshal_data.size
else
table = load(data)
checksum = Digest::MD5.digest(data)
checksum = Zlib.crc32(data)
size = data.size
if !table.is_a?(Hash)
raise Error, "PStore file seems to be corrupted."
......
is_windows
end
# Check whether Marshal.dump supports the 'canonical' option. This option
# makes sure that Marshal.dump always dumps data structures in the same order.
# This is important because otherwise, the checksums that we generate may differ.
def marshal_dump_supports_canonical_option?
begin
Marshal.dump(nil, -1, true)
result = true
rescue
result = false
end
self.class.__send__(:define_method, :marshal_dump_supports_canonical_option?) do
result
end
result
end
def save_data(original_checksum, original_file_size, file)
# We only want to save the new data if the size or checksum has changed.
# This results in less filesystem calls, which is good for performance.
if marshal_dump_supports_canonical_option?
new_data = Marshal.dump(@table, -1, true)
else
new_data = dump(@table)
end
new_checksum = Digest::MD5.digest(new_data)
new_data = dump(@table)
if new_data.size != original_file_size || new_checksum != original_checksum
if new_data.size != original_file_size || Zlib.crc32(new_data) != original_checksum
if @ultra_safe && !on_windows?
# Windows doesn't support atomic file renames.
save_data_with_atomic_file_rename_strategy(new_data, file)
......
def save_data_with_fast_strategy(data, file)
file.rewind
file.truncate(0)
file.write(data)
file.truncate(data.size)
end
# This method is just a wrapped around Marshal.dump
# to allow subclass overriding used in YAML::Store.
def dump(table) # :nodoc:
......
# :enddoc:
if __FILE__ == $0
if __FILE__ == $PROGRAM_NAME
db = PStore.new("/tmp/foo")
db.transaction do
p db.roots
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