install_packages() makes an assumption that a downloaded package has been extracted

[Brian Murray]

From backends/packaging-apt-dpkg.py:

1009 last_written = time.time()
1010 # fetch packages
1011 try:
1012 cache.fetch_archives(fetcher=fetcher)
1013 except apt.cache.FetchFailedException as e:
1014 apport.error('Package download error, try again later: %s', str(e))
1015 sys.exit(1) # transient error
1016
1017 if verbose:
1018 print('Extracting downloaded debs...')
1019 for i in fetcher.items:
1020 if not permanent_rootdir or os.path.getctime(i.destfile) > last_written:

The check "os.path.getctime(i.destfile) > last_written" assumes that i.destfile has been extracted in rootdir if it exists at all. However, its possible we retraced this crash one time without a permanent_rootdir, then switched to using one, in which case i.destfile would be < than last_written but it would not have been extracted in our new rootdir.

[Brian Murray (brian-murray)]

I think checking in pkg_versions for the package and version would resolve this issue.

[Brian Murray (brian-murray)]

This change fixes it.

=== modified file 'backends/packaging-apt-dpkg.py'
--- backends/packaging-apt-dpkg.py 2017-01-23 18:32:36 +0000
+++ backends/packaging-apt-dpkg.py 2017-01-24 22:34:59 +0000
@@ -1047,9 +1047,11 @@
         if verbose:
             print('Extracting downloaded debs...')
         for i in fetcher.items:
- if not permanent_rootdir or os.path.getctime(i.destfile) > last_written:
- out = subprocess.check_output(['dpkg-deb', '--show', i.destfile]).decode()
- (p, v) = out.strip().split()
+ out = subprocess.check_output(['dpkg-deb', '--show', i.destfile]).decode()
+ (p, v) = out.strip().split()
+ if not permanent_rootdir or p not in pkg_versions or os.path.getctime(i.destfile) > last_written:
+ #out = subprocess.check_output(['dpkg-deb', '--show', i.destfile]).decode()
+ #(p, v) = out.strip().split()
                 # don't extract the same version of the package if it is
                 # already extracted
                 if pkg_versions.get(p) == v: