dblink.mergeme(): use stack instead of recursion

Maybe this helps reduce memory consumption when merging packages with
lots of subdirectories like gentoo-sources (bug #320859).

diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py
index aae23e6bac3ae8a3eb3473f0a3cffbf4720846c3..8d908fcf3d9c4094cc4093944d18366bba4e7f93 100644 (file)
--- a/pym/portage/dbapi/vartree.py
+++ b/pym/portage/dbapi/vartree.py
@@ -4356,18 +4356,18 @@ class dblink(object):
                # this is supposed to merge a list of files.  There will be 2 forms of argument passing.
                if isinstance(stufftomerge, basestring):
                        #A directory is specified.  Figure out protection paths, listdir() it and process it.
-                       mergelist = os.listdir(join(srcroot, stufftomerge))
-                       offset = stufftomerge
+                       mergelist = [join(stufftomerge, child) for child in \
+                               os.listdir(join(srcroot, stufftomerge))]
                else:
-                       mergelist = stufftomerge
-                       offset = ""
+                       mergelist = stufftomerge[:]
 
-               for i, x in enumerate(mergelist):
+               while mergelist:
 
-                       mysrc = join(srcroot, offset, x)
-                       mydest = join(destroot, offset, x)
+                       relative_path = mergelist.pop()
+                       mysrc = join(srcroot, relative_path)
+                       mydest = join(destroot, relative_path)
                        # myrealdest is mydest without the $ROOT prefix (makes a difference if ROOT!="/")
-                       myrealdest = join(sep, offset, x)
+                       myrealdest = join(sep, relative_path)
                        # stat file once, test using S_* macros many times (faster that way)
                        mystat = os.lstat(mysrc)
                        mymode = mystat[stat.ST_MODE]
@@ -4575,9 +4575,9 @@ class dblink(object):
 
                                outfile.write("dir "+myrealdest+"\n")
                                # recurse and merge this directory
-                               if self.mergeme(srcroot, destroot, outfile, secondhand,
-                                       join(offset, x), cfgfiledict, thismtime):
-                                       return 1
+                               mergelist.extend(join(relative_path, child) for child in
+                                       os.listdir(join(srcroot, relative_path)))
+
                        elif stat.S_ISREG(mymode):
                                # we are merging a regular file
                                mymd5 = perform_md5(mysrc, calc_prelink=calc_prelink)