1// fsttopsort.cc
2
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14//
15// Copyright 2005-2010 Google, Inc.
16// Author: riley@google.com (Michael Riley)
17// Modified: jpr@google.com (Jake Ratkiewicz) to use FstClass
18//
19// \file
20// Topologically sorts an FST.
21//
22
23#include <fst/script/topsort.h>
24
25int main(int argc, char **argv) {
26  namespace s = fst::script;
27  using fst::script::FstClass;
28  using fst::script::MutableFstClass;
29
30  string usage = "Topologically sorts an FST.\n\n  Usage: ";
31  usage += argv[0];
32  usage += " [in.fst [out.fst]]\n";
33
34  std::set_new_handler(FailedNewHandler);
35  SetFlags(usage.c_str(), &argc, &argv, true);
36  if (argc > 3) {
37    ShowUsage();
38    return 1;
39  }
40
41  string in_fname = argc > 1 && strcmp(argv[1], "-") != 0 ? argv[1] : "";
42  string out_fname = argc > 2 ? argv[2] : "";
43
44  MutableFstClass *fst = MutableFstClass::Read(in_fname, true);
45  if (!fst) return 1;
46
47  bool acyclic = TopSort(fst);
48  if (!acyclic)
49    LOG(WARNING) << argv[0] << ": Input FST is cyclic";
50  fst->Write(out_fname);
51
52  return 0;
53}
54