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-rw-r--r--ext/python/Tools/freeze/bkfile.py47
1 files changed, 47 insertions, 0 deletions
diff --git a/ext/python/Tools/freeze/bkfile.py b/ext/python/Tools/freeze/bkfile.py
new file mode 100644
index 0000000..54af2fa
--- /dev/null
+++ b/ext/python/Tools/freeze/bkfile.py
@@ -0,0 +1,47 @@
+_orig_open = open
+
+class _BkFile:
+ def __init__(self, file, mode, bufsize):
+ import os
+ self.__filename = file
+ self.__backup = file + '~'
+ try:
+ os.unlink(self.__backup)
+ except os.error:
+ pass
+ try:
+ os.rename(file, self.__backup)
+ except os.error:
+ self.__backup = None
+ self.__file = _orig_open(file, mode, bufsize)
+ self.closed = self.__file.closed
+ self.fileno = self.__file.fileno
+ self.flush = self.__file.flush
+ self.isatty = self.__file.isatty
+ self.mode = self.__file.mode
+ self.name = self.__file.name
+ self.read = self.__file.read
+ self.readinto = self.__file.readinto
+ self.readline = self.__file.readline
+ self.readlines = self.__file.readlines
+ self.seek = self.__file.seek
+ self.softspace = self.__file.softspace
+ self.tell = self.__file.tell
+ self.truncate = self.__file.truncate
+ self.write = self.__file.write
+ self.writelines = self.__file.writelines
+
+ def close(self):
+ self.__file.close()
+ if self.__backup is None:
+ return
+ import filecmp
+ if filecmp.cmp(self.__backup, self.__filename, shallow = 0):
+ import os
+ os.unlink(self.__filename)
+ os.rename(self.__backup, self.__filename)
+
+def open(file, mode = 'r', bufsize = -1):
+ if 'w' not in mode:
+ return _orig_open(file, mode, bufsize)
+ return _BkFile(file, mode, bufsize)