1 // 2 // Copyright (C) 2010 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #include "update_engine/payload_generator/topological_sort.h" 18 19 #include <set> 20 #include <vector> 21 22 #include <base/logging.h> 23 24 using std::set; 25 using std::vector; 26 27 namespace chromeos_update_engine { 28 29 namespace { 30 void TopologicalSortVisit(const Graph& graph, 31 set<Vertex::Index>* visited_nodes, 32 vector<Vertex::Index>* nodes, 33 Vertex::Index node) { 34 if (visited_nodes->find(node) != visited_nodes->end()) 35 return; 36 37 visited_nodes->insert(node); 38 // Visit all children. 39 for (Vertex::EdgeMap::const_iterator it = graph[node].out_edges.begin(); 40 it != graph[node].out_edges.end(); ++it) { 41 TopologicalSortVisit(graph, visited_nodes, nodes, it->first); 42 } 43 // Visit this node. 44 nodes->push_back(node); 45 } 46 } // namespace 47 48 void TopologicalSort(const Graph& graph, vector<Vertex::Index>* out) { 49 set<Vertex::Index> visited_nodes; 50 51 for (Vertex::Index i = 0; i < graph.size(); i++) { 52 TopologicalSortVisit(graph, &visited_nodes, out, i); 53 } 54 } 55 56 } // namespace chromeos_update_engine 57