Fix pisi delta's not carrying file permission changes

pisi/atomicoperations.py

@@ -358,6 +358,13 @@ class Install(AtomicOperation):
 
                 os.rename(oldconfig, path)
 
+        # Package file's path may not be relocated or content may not be changed but
+        # permission may be changed
+        def update_permissions():
+            permissions = pisi.operations.delta.find_permission_changes(self.old_files, self.files)
+            for path, mode in permissions:
+                os.chmod(path, mode)
+
         # Delta package does not contain the files that have the same hash as in 
         # the old package's. Because it means the file has not changed. But some 
         # of these files may be relocated to some other directory in the new package. 
@@ -411,6 +418,7 @@ class Install(AtomicOperation):
 
         if self.package_fname.endswith(ctx.const.delta_package_suffix):
             relocate_files()
+            update_permissions()
 
         self.package.extract_install(ctx.config.dest_dir())
 

pisi/operations/delta.py

@@ -10,6 +10,7 @@
 # Please read the COPYING file.
 
 import os
+import stat
 
 import gettext
 __trans = gettext.translation("pisi", fallback=True)
@@ -137,3 +138,22 @@ def find_relocations(oldfiles, newfiles):
                     relocations.append((files_old[h][0], files_new[h][i]))
 
     return relocations
+
+def find_permission_changes(oldfiles, newfiles):
+
+    files_new = {}
+    for f in newfiles.list:
+        files_new.setdefault(f.hash, []).append(f)
+
+    hashes_new = set(map(lambda f:f.hash, newfiles.list))
+    hashes_old = set(map(lambda f:f.hash, oldfiles.list))
+    unchanged = hashes_new.intersection(hashes_old)
+
+    permissions = []
+    for h in unchanged:
+        for _file in files_new[h]:
+            path = "/%s" % _file.path
+            if oct(stat.S_IMODE(os.stat(path)[stat.ST_MODE])) != _file.mode:
+                permissions.append((path, int(_file.mode, 8)))
+
+    return permissions