AU: when cutting a cycle, add proper dependencies.

delta_diff_generator.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "update_engine/delta_diff_generator.h"
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <algorithm>
@@ skipping 634 matching lines @@
     graph->back().op.set_dst_length(graph->back().op.src_length());
 
     // make the dest node read from the scratch space
     DeltaDiffGenerator::SubstituteBlocks(
         &((*graph)[it->second].op),
         (*graph)[it->first].out_edges[it->second].extents,
         scratch);
 
     // delete the old edge
     CHECK_EQ(1, (*graph)[it->first].out_edges.erase(it->second));
+    
+    // Add an edge from dst to copy operation
+    (*graph)[it->second].out_edges.insert(make_pair(graph->size() - 1,
+                                                    EdgeProperties()));
   }
   return true;
 }
 
 // Stores all Extents in 'extents' into 'out'.
 void DeltaDiffGenerator::StoreExtents(
     vector<Extent>& extents,
     google::protobuf::RepeatedPtrField<Extent>* out) {
   for (vector<Extent>::const_iterator it = extents.begin();
        it != extents.end(); ++it) {
@@ skipping 273 matching lines @@
   
   LOG(INFO) << "All done. Successfully created delta file.";
   return true;
 }
 
 const char* const kBsdiffPath = "/usr/bin/bsdiff";
 const char* const kBspatchPath = "/usr/bin/bspatch";
 const char* const kDeltaMagic = "CrAU";
 
 };  // namespace chromeos_update_engine