source: gs2-extensions/tdb-edit/trunk/src/src/txt2tdb-src/txt2tdb.cpp@ 23996

/**********************************************************************
 *
 * txt2tdb.cpp -- A utility to convert a stream of text, ala buildproc
 *                encoded output, into a TDB file.
 *
 * A component of the Greenstone digital library software
 * from the New Zealand Digital Library Project at the 
 * University of Waikato, New Zealand.
 *
 * Copyright (C) 2011  The New Zealand Digital Library Project
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 **********************************************************************/

#if defined(GSDL_USE_OBJECTSPACE)
#include <ospace\std\iostream>
#elif defined(GSDL_USE_IOS_H)
#include <iostream.h>
#else
#include <iostream>
#endif

#include "tdb.h"
#include "text_t.h"

// use the standard namespace
#if !defined (GSDL_NAMESPACE_BROKEN)
#if defined(GSDL_USE_OBJECTSPACE)
using namespace ospace::std;
#else
using namespace std;
#endif
#endif

void
printUsage (char *program_name)
{
  cerr << "usage: " << program_name << " [options] database-name" << endl << endl;
  cerr << "options:" << endl;
  cerr << " -append        append to existing database" << endl << endl;
}
/** printUsage() **/

int
main (int argc, char *argv[])
{
  // sanity check
  if (argc != 2 && argc != 3)
  {
    printUsage (argv[0]);
    exit (0);
  }
  
  char *dbname;
  int append = 0;
  int delkey = 0;
  if (argc == 3)
  {
    if (strcmp (argv[1], "-append") == 0)
    {
      append = 1;
      dbname = argv[2];
    } 
    else
    {
      cerr << argv[1] << " is not a valid option." << endl << endl;
      printUsage(argv[0]);
      exit (0);
    }
  }
  else
  {
    dbname = argv[1];
  }
  
  // open the database
  int hash_size = 0;
  int tdb_flags = TDB_DEFAULT; // Default = 0
  if (append == 0)
  {
    tdb_flags = TDB_CLEAR_IF_FIRST;
  }
  int tdb_store_flags = TDB_DEFAULT; // used later when storing
  int open_flags = O_RDWR | O_CREAT;
  TDB_CONTEXT *tdb = tdb_open(dbname, hash_size, tdb_flags, open_flags, 0664);
  if (!tdb)
  {
    cerr << "couldn't create " << dbname << endl;
    exit (0);
  }
  
  char c;
  cin.get(c);
  while (!cin.eof())
  {
    int num_dashes = 0;
    text_t key = "";
    text_t value = "";
    
    // Parse out 'key' from [key]\n
    //  - scan for first occurrence of [
    while (!cin.eof() && c != '[')
    {
      cin.get(c);
    }
    // - skip [
    if (!cin.eof())
    {
      cin.get(c);
    }
    // - now look for closing ], building up 'key' as we go
    while (!cin.eof() && c != ']')
    {
      key.push_back ((unsigned char)c);
      cin.get(c);
    }
    if (!cin.eof())
    {
      // most likely an eol char, but if '-', then signifies record
      // is to be deleted, not added
      cin.get(c);
      if (c == '-') {   
        delkey = 1;
      }
      else {
        delkey = 0;
      }
    }
    while (!cin.eof() && (c == '\n' || c == '\r'))
    {
      cin.get(c);
    }
    // - read in the value, watching for 70 dashes (the end)
    text_t tmp = "";
    while (!cin.eof() && (num_dashes < 70))
    {
      if (c == '\n')
      {
        tmp.push_back ((unsigned char)c);
        num_dashes = 0; 
      }
      else if (c == '\r')
      { 
        // Here we are able to process both Windows-specific text files 
        // (containing carriage-return, newline) and Linux text files 
        // (containing only newline characters) by ignoring the Windows' 
        // carriage-return altogether so that we produce a uniform database
        // file from either system's type of text file. 
        // If we don't ignore the carriage return here, txt.gz files
        // produced on Windows cause a GS library running on Linux to break.
        num_dashes = 0;
      }
      else if (c == '-')
      {
        tmp.push_back ((unsigned char)c);
        ++num_dashes;
      }
      else
      {
        value += tmp;
        value.push_back ((unsigned char)c);
        tmp = "";
        num_dashes = 0;
      }
      cin.get(c);
    }
    
    // We should now have a key/value pair. If the key is not an empty string
    // store this key-value pair
    if (!key.empty())
    {
      // convert key to a datum datatype
      TDB_DATA key_data;
      // [why are cstrings from text_t not unsigned? from what I can see we
      //  explicitly cast to char * when we return]
      key_data.dptr = (unsigned char*)key.getcstr();
      if (key_data.dptr == NULL)
      {
        cerr << "NULL key_data.dptr" << endl;
        exit (0);
      }
      key_data.dsize = key.size();
      // - delete the given key if we've been asked to
      if (delkey)
      {
        if (tdb_delete(tdb, key_data) < 0)
        {
          cerr << "tdb_delete returned an error" << endl;
        }
      }
      // - otherwise add
      else {
        // - convert value to a datum datatype
        TDB_DATA value_data;
        value_data.dptr = (unsigned char*)value.getcstr();
        if (value_data.dptr == NULL)
        {
          cerr << "NULL value_data.dptr" << endl;
          exit (0);
        }
        value_data.dsize = value.size();
        // - store the value
        if (tdb_store(tdb, key_data, value_data, tdb_store_flags) < 0)
        {
          cerr << "tdb_store returned an error" << endl;
          exit (0);
        }
        free(value_data.dptr);
      }
      free(key_data.dptr);
    }
  }

  // Close the database connection
  if (tdb_close(tdb) < 0)
  {
    cerr << "tdb_close returned an error" << endl;
    exit (0);
  }
  
  return 0;
}