// 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>
inline void FarWriteFst(const Fst<Arc>* fst, string key,
string* okey, int* nrep,
const int32 &generate_filenames, int i,
const string &filename_prefix,
const string &filename_suffix) {
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.append(tmp.str().data(), tmp.str().size());
}
ofilename = key;
}
fst->Write(filename_prefix + ofilename + filename_suffix);
}
template<class Arc>
void FarExtract(const vector<string> &ifilenames,
const int32 &generate_filenames,
const string &keys,
const string &key_separator,
const string &range_delimiter,
const string &filename_prefix,
const string &filename_suffix) {
FarReader<Arc> *far_reader = FarReader<Arc>::Open(ifilenames);
if (!far_reader) return;
string okey;
int nrep = 0;
vector<char *> key_vector;
// User has specified a set of fsts to extract, where some of the "fsts" could
// be ranges.
if (!keys.empty()) {
char *keys_cstr = new char[keys.size()+1];
strcpy(keys_cstr, keys.c_str());
SplitToVector(keys_cstr, key_separator.c_str(), &key_vector, true);
int i = 0;
for (int k = 0; k < key_vector.size(); ++k, ++i) {
string key = string(key_vector[k]);
char *key_cstr = new char[key.size()+1];
strcpy(key_cstr, key.c_str());
vector<char *> range_vector;
SplitToVector(key_cstr, range_delimiter.c_str(), &range_vector, false);
if (range_vector.size() == 1) { // Not a range
if (!far_reader->Find(key)) {
LOG(ERROR) << "FarExtract: Cannot find key: " << key;
return;
}
const Fst<Arc> &fst = far_reader->GetFst();
FarWriteFst(&fst, key, &okey, &nrep, generate_filenames, i,
filename_prefix, filename_suffix);
} else if (range_vector.size() == 2) { // A legal range
string begin_key = string(range_vector[0]);
string end_key = string(range_vector[1]);
if (begin_key.empty() || end_key.empty()) {
LOG(ERROR) << "FarExtract: Illegal range specification: " << key;
return;
}
if (!far_reader->Find(begin_key)) {
LOG(ERROR) << "FarExtract: Cannot find key: " << begin_key;
return;
}
for ( ; !far_reader->Done(); far_reader->Next(), ++i) {
string ikey = far_reader->GetKey();
if (end_key < ikey) break;
const Fst<Arc> &fst = far_reader->GetFst();
FarWriteFst(&fst, ikey, &okey, &nrep, generate_filenames, i,
filename_prefix, filename_suffix);
}
} else {
LOG(ERROR) << "FarExtract: Illegal range specification: " << key;
return;
}
delete key_cstr;
}
delete keys_cstr;
return;
}
// Nothing specified: extract everything.
for (int i = 1; !far_reader->Done(); far_reader->Next(), ++i) {
string key = far_reader->GetKey();
const Fst<Arc> &fst = far_reader->GetFst();
FarWriteFst(&fst, key, &okey, &nrep, generate_filenames, i,
filename_prefix, filename_suffix);
}
return;
}
} // namespace fst
#endif // FST_EXTENSIONS_FAR_EXTRACT_H__