From: David-Sarah Hopwood Date: Fri, 16 Nov 2012 23:26:41 +0000 (+0000) Subject: util/fileutil.py: add get_used_space. This version does not use FilePath. X-Git-Url: https://git.rkrishnan.org/components?a=commitdiff_plain;h=56bb6ffc03bef25e4dd43c4074a150aa254c532d;p=tahoe-lafs%2Ftahoe-lafs.git util/fileutil.py: add get_used_space. This version does not use FilePath. Signed-off-by: David-Sarah Hopwood --- diff --git a/src/allmydata/util/fileutil.py b/src/allmydata/util/fileutil.py index 74132733..a8d093e1 100644 --- a/src/allmydata/util/fileutil.py +++ b/src/allmydata/util/fileutil.py @@ -521,3 +521,38 @@ def get_available_space(whichdir, reserved_space): except EnvironmentError: log.msg("OS call to get disk statistics failed") return 0 + + +def get_used_space(path): + if path is None: + return 0 + try: + s = os.stat(path) + except EnvironmentError: + if not os.path.exists(path): + return 0 + raise + else: + # POSIX defines st_blocks (originally a BSDism): + # + # but does not require stat() to give it a "meaningful value" + # + # and says: + # "The unit for the st_blocks member of the stat structure is not defined + # within IEEE Std 1003.1-2001. In some implementations it is 512 bytes. + # It may differ on a file system basis. There is no correlation between + # values of the st_blocks and st_blksize, and the f_bsize (from ) + # structure members." + # + # The Linux docs define it as "the number of blocks allocated to the file, + # [in] 512-byte units." It is also defined that way on MacOS X. Python does + # not set the attribute on Windows. + # + # We consider platforms that define st_blocks but give it a wrong value, or + # measure it in a unit other than 512 bytes, to be broken. See also + # . + + if hasattr(s, 'st_blocks'): + return s.st_blocks * 512 + else: + return s.st_size