third_party/waf/waflib/Tools/md5_tstamp.py

   1 #! /usr/bin/env python
   2 # encoding: utf-8
   3 # WARNING! Do not edit! https://waf.io/book/index.html#_obtaining_the_waf_file
   4
   5 #! /usr/bin/env python
   6 # encoding: utf-8
   7
   8 """
   9 Re-calculate md5 hashes of files only when the file times or the file
  10 size have changed.
  11
  12 The hashes can also reflect either the file contents (STRONGEST=True) or the
  13 file time and file size.
  14
  15 The performance benefits of this module are usually insignificant.
  16 """
  17
  18 import os, stat
  19 from waflib import Utils, Build, Node
  20
  21 STRONGEST = True
  22
  23 Build.SAVED_ATTRS.append('hashes_md5_tstamp')
  24 def h_file(self):
  25         filename = self.abspath()
  26         st = os.stat(filename)
  27
  28         cache = self.ctx.hashes_md5_tstamp
  29         if filename in cache and cache[filename][0] == st.st_mtime:
  30                 return cache[filename][1]
  31
  32         if STRONGEST:
  33                 ret = Utils.h_file(filename)
  34         else:
  35                 if stat.S_ISDIR(st[stat.ST_MODE]):
  36                         raise IOError('Not a file')
  37                 ret = Utils.md5(str((st.st_mtime, st.st_size)).encode()).digest()
  38
  39         cache[filename] = (st.st_mtime, ret)
  40         return ret
  41 h_file.__doc__ = Node.Node.h_file.__doc__
  42 Node.Node.h_file = h_file
  43