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diff --git a/kaldi_io/src/tools/openfst/include/fst/generic-register.h b/kaldi_io/src/tools/openfst/include/fst/generic-register.h
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+
+// 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: jpr@google.com (Jake Ratkiewicz)
+
+#ifndef FST_LIB_GENERIC_REGISTER_H_
+#define FST_LIB_GENERIC_REGISTER_H_
+
+#include <map>
+#include <string>
+
+#include <fst/compat.h>
+#include <fst/types.h>
+
+// Generic class representing a globally-stored correspondence between
+// objects of KeyType and EntryType.
+// KeyType must:
+//  a) be such as can be stored as a key in a map<>
+//  b) be concatenable with a const char* with the + operator
+//     (or you must subclass and redefine LoadEntryFromSharedObject)
+// EntryType must be default constructible.
+//
+// The third template parameter should be the type of a subclass of this class
+// (think CRTP). This is to allow GetRegister() to instantiate and return
+// an object of the appropriate type.
+
+namespace fst {
+
+template<class KeyType, class EntryType, class RegisterType>
+class GenericRegister {
+ public:
+  typedef KeyType Key;
+  typedef EntryType Entry;
+
+  static RegisterType *GetRegister() {
+    FstOnceInit(&register_init_,
+                   &RegisterType::Init);
+
+    return register_;
+  }
+
+  void SetEntry(const KeyType &key,
+                const EntryType &entry) {
+    MutexLock l(register_lock_);
+
+    register_table_.insert(make_pair(key, entry));
+  }
+
+  EntryType GetEntry(const KeyType &key) const {
+    const EntryType *entry = LookupEntry(key);
+    if (entry) {
+      return *entry;
+    } else {
+      return LoadEntryFromSharedObject(key);
+    }
+  }
+
+  virtual ~GenericRegister() { }
+
+ protected:
+  // Override this if you want to be able to load missing definitions from
+  // shared object files.
+  virtual EntryType LoadEntryFromSharedObject(const KeyType &key) const {
+    string so_filename = ConvertKeyToSoFilename(key);
+
+    void *handle = dlopen(so_filename.c_str(), RTLD_LAZY);
+    if (handle == 0) {
+      LOG(ERROR) << "GenericRegister::GetEntry : " << dlerror();
+      return EntryType();
+    }
+
+    // We assume that the DSO constructs a static object in its global
+    // scope that does the registration. Thus we need only load it, not
+    // call any methods.
+    const EntryType *entry = this->LookupEntry(key);
+    if (entry == 0) {
+      LOG(ERROR) << "GenericRegister::GetEntry : "
+                 << "lookup failed in shared object: " << so_filename;
+      return EntryType();
+    }
+    return *entry;
+  }
+
+  // Override this to define how to turn a key into an SO filename.
+  virtual string ConvertKeyToSoFilename(const KeyType& key) const = 0;
+
+  virtual const EntryType *LookupEntry(
+      const KeyType &key) const {
+    MutexLock l(register_lock_);
+
+    typename RegisterMapType::const_iterator it = register_table_.find(key);
+
+    if (it != register_table_.end()) {
+      return &it->second;
+    } else {
+      return 0;
+    }
+  }
+
+ private:
+  typedef map<KeyType, EntryType> RegisterMapType;
+
+  static void Init() {
+    register_lock_ = new Mutex;
+    register_ = new RegisterType;
+  }
+
+  static FstOnceType register_init_;
+  static Mutex *register_lock_;
+  static RegisterType *register_;
+
+  RegisterMapType register_table_;
+};
+
+template<class KeyType, class EntryType, class RegisterType>
+FstOnceType GenericRegister<KeyType, EntryType,
+                               RegisterType>::register_init_ = FST_ONCE_INIT;
+
+template<class KeyType, class EntryType, class RegisterType>
+Mutex *GenericRegister<KeyType, EntryType, RegisterType>::register_lock_ = 0;
+
+template<class KeyType, class EntryType, class RegisterType>
+RegisterType *GenericRegister<KeyType, EntryType, RegisterType>::register_ = 0;
+
+//
+// GENERIC REGISTRATION
+//
+
+// Generic register-er class capable of creating new register entries in the
+// given RegisterType template parameter. This type must define types Key
+// and Entry, and have appropriate static GetRegister() and instance
+// SetEntry() functions. An easy way to accomplish this is to have RegisterType
+// be the type of a subclass of GenericRegister.
+template<class RegisterType>
+class GenericRegisterer {
+ public:
+  typedef typename RegisterType::Key Key;
+  typedef typename RegisterType::Entry Entry;
+
+  GenericRegisterer(Key key, Entry entry) {
+    RegisterType *reg = RegisterType::GetRegister();
+    reg->SetEntry(key, entry);
+  }
+};
+
+}  // namespace fst
+
+#endif  // FST_LIB_GENERIC_REGISTER_H_