1 files changed, 53 insertions, 0 deletions
diff --git a/src/bin/fsttopsort.cc b/src/bin/fsttopsort.cc
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+++ b/src/bin/fsttopsort.cc
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+// fsttopsort.cc
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2005-2010 Google, Inc.
+// Author: riley@google.com (Michael Riley)
+// Modified: jpr@google.com (Jake Ratkiewicz) to use FstClass
+//
+// \file
+// Topologically sorts an FST.
+//
+
+#include <fst/script/topsort.h>
+
+int main(int argc, char **argv) {
+  namespace s = fst::script;
+  using fst::script::FstClass;
+  using fst::script::MutableFstClass;
+
+  string usage = "Topologically sorts an FST.\n\n  Usage: ";
+  usage += argv[0];
+  usage += " [in.fst [out.fst]]\n";
+
+  std::set_new_handler(FailedNewHandler);
+  SetFlags(usage.c_str(), &argc, &argv, true);
+  if (argc > 3) {
+    ShowUsage();
+    return 1;
+  }
+
+  string in_fname = argc > 1 && strcmp(argv[1], "-") != 0 ? argv[1] : "";
+  string out_fname = argc > 2 ? argv[2] : "";
+
+  MutableFstClass *fst = MutableFstClass::Read(in_fname, true);
+  if (!fst) return 1;
+
+  bool acyclic = TopSort(fst);
+  if (!acyclic)
+    LOG(WARNING) << argv[0] << ": Input FST is cyclic";
+  fst->Write(out_fname);
+
+  return 0;
+}