1 #
2 # Copyright (c) 2001 Bizar Software Pty Ltd (http://www.bizarsoftware.com.au/)
3 # This module is free software, and you may redistribute it and/or modify
4 # under the same terms as Python, so long as this copyright message and
5 # disclaimer are retained in their original form.
6 #
7 # IN NO EVENT SHALL BIZAR SOFTWARE PTY LTD BE LIABLE TO ANY PARTY FOR
8 # DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
9 # OUT OF THE USE OF THIS CODE, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE
10 # POSSIBILITY OF SUCH DAMAGE.
11 #
12 # BIZAR SOFTWARE PTY LTD SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
13 # BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
14 # FOR A PARTICULAR PURPOSE. THE CODE PROVIDED HEREUNDER IS ON AN "AS IS"
15 # BASIS, AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
16 # SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
17 #
18 # $Id: install_util.py,v 1.10 2004-02-11 23:55:08 richard Exp $
20 """Support module to generate and check fingerprints of installed files.
21 """
22 __docformat__ = 'restructuredtext'
24 import os, sha, shutil
26 # ".filter", ".index", ".item", ".newitem" are roundup-specific
27 sgml_file_types = [".xml", ".ent", ".html", ".filter", ".index", ".item", ".newitem"]
28 hash_file_types = [".py", ".sh", ".conf", ".cgi", '']
29 slast_file_types = [".css"]
31 digested_file_types = sgml_file_types + hash_file_types + slast_file_types
33 def extractFingerprint(lines):
34 # get fingerprint from last line
35 if lines[-1].startswith("#SHA: "):
36 # handle .py/.sh comment
37 return lines[-1][6:].strip()
38 elif lines[-1].startswith("<!-- SHA: "):
39 # handle xml/html files
40 fingerprint = lines[-1][10:]
41 fingerprint = fingerprint.replace('-->', '')
42 return fingerprint.strip()
43 elif lines[-1].startswith("/* SHA: "):
44 # handle css files
45 fingerprint = lines[-1][8:]
46 fingerprint = fingerprint.replace('*/', '')
47 return fingerprint.strip()
48 return None
50 def checkDigest(filename):
51 """Read file, check for valid fingerprint, return TRUE if ok"""
52 # open and read file
53 inp = open(filename, "r")
54 lines = inp.readlines()
55 inp.close()
57 fingerprint = extractFingerprint(lines)
58 if fingerprint is None:
59 return 0
60 del lines[-1]
62 # calculate current digest
63 digest = sha.new()
64 for line in lines:
65 digest.update(line)
67 # compare current to stored digest
68 return fingerprint == digest.hexdigest()
71 class DigestFile:
72 """ A class that you can use like open() and that calculates
73 and writes a SHA digest to the target file.
74 """
76 def __init__(self, filename):
77 self.filename = filename
78 self.digest = sha.new()
79 self.file = open(self.filename, "w")
81 def write(self, data):
82 lines = data.splitlines()
83 # if the file is coming from an installed tracker being used as a
84 # template, then we will want to re-calculate the SHA
85 fingerprint = extractFingerprint(lines)
86 if fingerprint is not None:
87 data = '\n'.join(lines[:-1]) + '\n'
88 self.file.write(data)
89 self.digest.update(data)
91 def close(self):
92 file, ext = os.path.splitext(self.filename)
94 if ext in sgml_file_types:
95 self.file.write("<!-- SHA: %s -->\n" % (self.digest.hexdigest(),))
96 elif ext in hash_file_types:
97 self.file.write("#SHA: %s\n" % (self.digest.hexdigest(),))
98 elif ext in slast_file_types:
99 self.file.write("/* SHA: %s */\n" % (self.digest.hexdigest(),))
101 self.file.close()
104 def copyDigestedFile(src, dst, copystat=1):
105 """ Copy data from `src` to `dst`, adding a fingerprint to `dst`.
106 If `copystat` is true, the file status is copied, too
107 (like shutil.copy2).
108 """
109 if os.path.isdir(dst):
110 dst = os.path.join(dst, os.path.basename(src))
112 dummy, ext = os.path.splitext(src)
113 if ext not in digested_file_types:
114 if copystat:
115 return shutil.copy2(src, dst)
116 else:
117 return shutil.copyfile(src, dst)
119 fsrc = None
120 fdst = None
121 try:
122 fsrc = open(src, 'r')
123 fdst = DigestFile(dst)
124 shutil.copyfileobj(fsrc, fdst)
125 finally:
126 if fdst: fdst.close()
127 if fsrc: fsrc.close()
129 if copystat: shutil.copystat(src, dst)
132 def test():
133 import sys
135 testdata = open(sys.argv[0], 'r').read()
137 for ext in digested_file_types:
138 testfile = "__digest_test" + ext
140 out = DigestFile(testfile)
141 out.write(testdata)
142 out.close()
144 assert checkDigest(testfile), "digest ok w/o modification"
146 mod = open(testfile, 'r+')
147 mod.seek(0)
148 mod.write('# changed!')
149 mod.close()
151 assert not checkDigest(testfile), "digest fails after modification"
153 os.remove(testfile)
156 if __name__ == '__main__':
157 test()
159 # vim: set filetype=python ts=4 sw=4 et si