1 files changed, 85 insertions, 0 deletions
diff --git a/src/include/fst/extensions/far/extract.h b/src/include/fst/extensions/far/extract.h
new file mode 100644
index 0000000..022ca60
--- /dev/null
+++ b/src/include/fst/extensions/far/extract.h
@@ -0,0 +1,85 @@
+// extract-main.h
+
+// 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 the new arc-dispatch
+
+// \file
+// Extracts component FSTs from an finite-state archive.
+//
+
+#ifndef FST_EXTENSIONS_FAR_EXTRACT_H__
+#define FST_EXTENSIONS_FAR_EXTRACT_H__
+
+#include <string>
+#include <vector>
+using std::vector;
+
+#include <fst/extensions/far/far.h>
+
+namespace fst {
+
+template<class Arc>
+void FarExtract(const vector<string> &ifilenames,
+                const int32 &generate_filenames,
+                const string &begin_key,
+                const string &end_key,
+                const string &filename_prefix,
+                const string &filename_suffix) {
+  FarReader<Arc> *far_reader = FarReader<Arc>::Open(ifilenames);
+  if (!far_reader) return;
+
+  if (!begin_key.empty())
+    far_reader->Find(begin_key);
+
+  string okey;
+  int nrep = 0;
+  for (int i = 1; !far_reader->Done(); far_reader->Next(), ++i) {
+    string key = far_reader->GetKey();
+    if (!end_key.empty() && end_key < key)
+      break;
+    const Fst<Arc> &fst = far_reader->GetFst();
+
+    if (key == okey)
+      ++nrep;
+    else
+      nrep = 0;
+
+    okey = key;
+
+    string ofilename;
+    if (generate_filenames) {
+      ostringstream tmp;
+      tmp.width(generate_filenames);
+      tmp.fill('0');
+      tmp << i;
+      ofilename = tmp.str();
+    } else {
+      if (nrep > 0) {
+        ostringstream tmp;
+        tmp << '.' << nrep;
+        key += tmp.str();
+      }
+      ofilename = key;
+    }
+    fst.Write(filename_prefix + ofilename + filename_suffix);
+  }
+
+  return;
+}
+
+}  // namespace fst
+
+#endif  // FST_EXTENSIONS_FAR_EXTRACT_H__