~drizzle-trunk/drizzle/development

/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008 Sun Microsystems

 *

 *  Authors:

 *

 *  Jay Pipes <jay.pipes@sun.com>

 *

 *  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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

/**

 * @file 

 *

 * Implementation of the server's date and time string matching utility.

 */

#include <string> /** C++ string class used */

#include <string.h>

#include <vector>

#include <pcre.h>

#include "drizzled/global.h"

#include "drizzled/temporal_format.h"

#include "drizzled/temporal.h"

namespace drizzled

{

  TemporalFormat::TemporalFormat(const char *pattern)

  :

  _pattern(pattern)

, _error_offset(0)

, _error(NULL)

, _year_part_index(0)

, _month_part_index(0)

, _day_part_index(0)

, _hour_part_index(0)

, _minute_part_index(0)

, _second_part_index(0)

, _usecond_part_index(0)

, _nsecond_part_index(0)

{

  /* Make sure we've got no junk in the match_vector. */

  memset(_match_vector, 0, sizeof(_match_vector));

  /* Compile our regular expression */

  _re= pcre_compile(pattern

                    , 0 /* Default options */

                    , &_error

                    , &_error_offset

                    , NULL /* Use default character table */

                    );

}

bool TemporalFormat::matches(const char *data, size_t data_len, Temporal *to)

{

  if (! is_valid()) 

    return false;

  /* Simply check the subject against the compiled regular expression */

  int32_t result= pcre_exec(_re

                            , NULL /* No extra data */

                            , data

                            , data_len

                            , 0 /* Start at offset 0 of subject...*/

                            , 0 /* Default options */

                            , _match_vector

                            , OUT_VECTOR_SIZE

                            );

  if (result < 0)

  {

    switch (result)

    {

      case PCRE_ERROR_NOMATCH:

        return false; /* No match, just return false */

      default:

        return false;

    }

    return false;

  }

  int32_t expected_match_count= (_year_part_index > 1 ? 1 : 0)

                              + (_month_part_index > 1 ? 1 : 0)

                              + (_day_part_index > 1 ? 1 : 0)

                              + (_hour_part_index > 1 ? 1 : 0)

                              + (_minute_part_index > 1 ? 1 : 0)

                              + (_second_part_index > 1 ? 1 : 0)

                              + (_usecond_part_index > 1 ? 1 : 0)

                              + (_nsecond_part_index > 1 ? 1 : 0)

                              + 1; /* Add one for the entire match... */

  if (result != expected_match_count)

    return false;

  /* C++ string class easy to use substr() method is very useful here */

  std::string copy_data(data, data_len);

  /* 

   * OK, we have the expected substring matches, so grab

   * the various temporal parts from the subject string

   *

   * @note 

   *

   * TemporalFormatMatch is a friend class to Temporal, so

   * we can access the temporal instance's protected data.

   */

  if (_year_part_index > 1)

  {

    size_t year_start= _match_vector[_year_part_index];

    size_t year_len= _match_vector[_year_part_index + 1] - _match_vector[_year_part_index];

    to->_years= atoi(copy_data.substr(year_start, year_len).c_str());

    if (year_len == 2)

      to->_years+= (to->_years >= DRIZZLE_YY_PART_YEAR ? 1900 : 2000);

  }

  if (_month_part_index > 1)

  {

    size_t month_start= _match_vector[_month_part_index];

    size_t month_len= _match_vector[_month_part_index + 1] - _match_vector[_month_part_index];

    to->_months= atoi(copy_data.substr(month_start, month_len).c_str());

  }

  if (_day_part_index > 1)

  {

    size_t day_start= _match_vector[_day_part_index];

    size_t day_len= _match_vector[_day_part_index + 1] - _match_vector[_day_part_index];

    to->_days= atoi(copy_data.substr(day_start, day_len).c_str());

  }

  if (_hour_part_index > 1)

  {

    size_t hour_start= _match_vector[_hour_part_index];

    size_t hour_len= _match_vector[_hour_part_index + 1] - _match_vector[_hour_part_index];

    to->_hours= atoi(copy_data.substr(hour_start, hour_len).c_str());

  }

  if (_minute_part_index > 1)

  {

    size_t minute_start= _match_vector[_minute_part_index];

    size_t minute_len= _match_vector[_minute_part_index + 1] - _match_vector[_minute_part_index];

    to->_minutes= atoi(copy_data.substr(minute_start, minute_len).c_str());

  }

  if (_second_part_index > 1)

  {

    size_t second_start= _match_vector[_second_part_index];

    size_t second_len= _match_vector[_second_part_index + 1] - _match_vector[_second_part_index];

    to->_seconds= atoi(copy_data.substr(second_start, second_len).c_str());

  }

  if (_usecond_part_index > 1)

  {

    size_t usecond_start= _match_vector[_usecond_part_index];

    size_t usecond_len= _match_vector[_usecond_part_index + 1] - _match_vector[_usecond_part_index];

    /* 

     * For microseconds, which are millionth of 1 second, 

     * we must ensure that we produce a correct result, 

     * even if < 6 places were specified.  For instance, if we get .1, 

     * we must produce 100000. .11 should produce 110000, etc.

     */

    uint32_t multiplier= 1;

    int32_t x= usecond_len;

    while (x < 6)

    {

      multiplier*= 10;

      ++x;

    }

    to->_useconds= atoi(copy_data.substr(usecond_start, usecond_len).c_str()) * multiplier;

  }

  if (_nsecond_part_index > 1)

  {

    size_t nsecond_start= _match_vector[_nsecond_part_index];

    size_t nsecond_len= _match_vector[_nsecond_part_index + 1] - _match_vector[_nsecond_part_index];

    /* 

     * For nanoseconds, which are 1 billionth of a second, 

     * we must ensure that we produce a correct result, 

     * even if < 9 places were specified.  For instance, if we get .1, 

     * we must produce 100000000. .11 should produce 110000000, etc.

     */

    uint32_t multiplier= 1;

    int32_t x= nsecond_len;

    while (x < 9)

    {

      multiplier*= 10;

      ++x;

    }

    to->_nseconds= atoi(copy_data.substr(nsecond_start, nsecond_len).c_str()) * multiplier;

  }

  return true;

}

} /* end namespace drizzled */

#define COUNT_KNOWN_FORMATS 14

struct temporal_format_args

{

  const char *pattern;

  int32_t year_part_index;

  int32_t month_part_index;

  int32_t day_part_index;

  int32_t hour_part_index;

  int32_t minute_part_index;

  int32_t second_part_index;

  int32_t usecond_part_index;

  int32_t nsecond_part_index;

};

/**

 * A collection of all known format strings.

 *

 * @note

 *

 * IMPORTANT: Make sure TIMESTAMP and DATETIME formats precede DATE formats and TIME formats, 

 * as the matching functionality matches on the first hit.

 *

 * @note 

 *

 * Remember to increment COUNT_KNOWN_FORMATS when you add a known format!

 */

static struct temporal_format_args __format_args[COUNT_KNOWN_FORMATS]= 

{

  {"^(\\d{4})(\\d{2})(\\d{2})(\\d{2})(\\d{2})(\\d{2})\\.(\\d{1,6})$", 1, 2, 3, 4, 5, 6, 7, 0} /* YYYYMMDDHHmmSS.uuuuuu */

, {"^(\\d{4})(\\d{2})(\\d{2})(\\d{2})(\\d{2})(\\d{2})$", 1, 2, 3, 4, 5, 6, 0, 0} /* YYYYMMDDHHmmSS */

, {"^(\\d{4})[-/.](\\d{1,2})[-/.](\\d{1,2})[T|\\s+](\\d{2}):(\\d{2}):(\\d{2})\\.(\\d{1,6})$", 1, 2, 3, 4, 5, 6, 7, 0} /* YYYY[/-.]MM[/-.]DD[T]HH:mm:SS.uuuuuu */

, {"^(\\d{4})[-/.](\\d{1,2})[-/.](\\d{1,2})[T|\\s+](\\d{2}):(\\d{2}):(\\d{2})$", 1, 2, 3, 4, 5, 6, 0, 0} /* YYYY[/-.]MM[/-.]DD[T]HH:mm:SS */

, {"^(\\d{4})[-/.](\\d{1,2})[-/.](\\d{1,2})$", 1, 2, 3, 0, 0, 0, 0, 0} /* YYYY-MM-DD, YYYY.MM.DD, YYYY/MM/DD */

, {"^(\\d{4})(\\d{2})(\\d{2})$", 1, 2, 3, 0, 0, 0, 0, 0} /* YYYYMMDD */

, {"^(\\d{2})[-/.]*(\\d{2})[-/.]*(\\d{4})$", 3, 1, 2, 0, 0, 0, 0, 0} /* MM[-/.]DD[-/.]YYYY (US common format)*/

, {"^(\\d{2})[-/.]*(\\d{2})[-/.]*(\\d{2})$", 1, 2, 3, 0, 0, 0, 0, 0} /* YY[-/.]MM[-/.]DD */

, {"^(\\d{2})[-/.]*(\\d{1,2})[-/.]*(\\d{1,2})$", 1, 2, 3, 0, 0, 0, 0, 0} /* YY[-/.][M]M[-/.][D]D */

, {"^(\\d{2}):*(\\d{2}):*(\\d{2})\\.(\\d{1,6})$", 0, 0, 0, 1, 2, 3, 4, 0} /* HHmmSS.uuuuuu, HH:mm:SS.uuuuuu */

, {"^(\\d{1,2}):*(\\d{2}):*(\\d{2})$", 0, 0, 0, 1, 2, 3, 0, 0} /* [H]HmmSS, [H]H:mm:SS */

, {"^(\\d{1,2}):*(\\d{2})$", 0, 0, 0, 0, 1, 2, 0, 0} /* [m]mSS, [m]m:SS */

, {"^(\\d{1,2})$", 0, 0, 0, 0, 0, 1, 0, 0} /* SS, S */

, {"^(\\d{1,2})\\.(\\d{1,6})$", 0, 0, 0, 0, 0, 1, 2, 0} /* [S]S.uuuuuu */

};

std::vector<drizzled::TemporalFormat*> known_datetime_formats;

std::vector<drizzled::TemporalFormat*> known_date_formats;

std::vector<drizzled::TemporalFormat*> known_time_formats;

/**

 * We allocate and initialize all known date/time formats.

 *

 * @TODO Cut down calls to new. Allocate as a block...

 */

bool init_temporal_formats()

{

  /* Compile all the regular expressions for the datetime formats */

  drizzled::TemporalFormat *tmp;

  struct temporal_format_args current_format_args;

  int32_t x;

  for (x= 0; x<COUNT_KNOWN_FORMATS; ++x)

  {

    current_format_args= __format_args[x];

    tmp= new drizzled::TemporalFormat(current_format_args.pattern);

    tmp->set_year_part_index(current_format_args.year_part_index);

    tmp->set_month_part_index(current_format_args.month_part_index);

    tmp->set_day_part_index(current_format_args.day_part_index);

    tmp->set_hour_part_index(current_format_args.hour_part_index);

    tmp->set_minute_part_index(current_format_args.minute_part_index);

    tmp->set_second_part_index(current_format_args.second_part_index);

    tmp->set_usecond_part_index(current_format_args.usecond_part_index);

    tmp->set_nsecond_part_index(current_format_args.nsecond_part_index);

    if (current_format_args.year_part_index > 0) /* A date must have a year */

    {

      known_datetime_formats.push_back(tmp);

      if (current_format_args.second_part_index == 0) /* A time must have seconds. */

        known_date_formats.push_back(tmp);

    }

    if (current_format_args.second_part_index > 0) /* A time must have seconds, but may not have minutes or hours */

      if (current_format_args.year_part_index == 0) /* A time may not have a date part, and date parts must have a year */

        known_time_formats.push_back(tmp);

  }

  return true;

}