~drizzle-trunk/drizzle/development

/* Copyright (C) 2000 MySQL AB

   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; version 2 of the License.

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/* This implements 'user defined functions' */

#include <drizzled/server_includes.h>

#include <drizzled/gettext.h>

#include <mysys/hash.h>

#include <drizzled/sql_udf.h>

static bool udf_startup= false; /* We do not lock because startup is single threaded */

static MEM_ROOT mem;

static HASH udf_hash;

extern "C" unsigned char* get_hash_key(const unsigned char *buff, size_t *length,

                               bool )

{

  udf_func *udf= (udf_func*) buff;

  *length= (uint) udf->name.length;

  return (unsigned char*) udf->name.str;

}

void udf_init()

{

  init_sql_alloc(&mem, UDF_ALLOC_BLOCK_SIZE, 0);

  if (hash_init(&udf_hash, system_charset_info, 32, 0, 0, get_hash_key, NULL, 0))

  {

    errmsg_printf(ERRMSG_LVL_ERROR, _("Can't allocate memory for udf structures"));

    hash_free(&udf_hash);

    free_root(&mem, MYF(0));

    return;

  }

}

/* called by mysqld.cc clean_up() */

void udf_free()

{

  hash_free(&udf_hash);

  free_root(&mem, MYF(0));

}

/* This is only called if using_udf_functions != 0 */

udf_func *find_udf(const char *name, uint32_t length)

{

  udf_func *udf;

  if (udf_startup == false)

    return NULL;

  udf= (udf_func*) hash_search(&udf_hash,

                               (unsigned char*) name,

                               length ? length : (uint) strlen(name));

  return (udf);

}

static bool add_udf(udf_func *udf)

{

  if (my_hash_insert(&udf_hash, (unsigned char*) udf))

    return false;

  using_udf_functions= 1;

  return true;

}

int initialize_udf(st_plugin_int *plugin)

{

  udf_func *f;

  if (udf_startup == false)

  {

    udf_init();

    udf_startup= true;

  }

  if (plugin->plugin->init)

  {

    int r;

    if ((r= plugin->plugin->init((void *)&f)))

    {

      errmsg_printf(ERRMSG_LVL_ERROR, "Plugin '%s' init function returned error %d.",

		    plugin->name.str, r);

      return r;

    }

  }

  else

    return 1;

  if (!add_udf(f))

    return 1;

  plugin->state= PLUGIN_IS_READY;

  return 0;

}

int finalize_udf(st_plugin_int *plugin)

{

  udf_func *udff = (udf_func *)plugin->data;

  /* TODO: Issue warning on failure */

  if (udff && plugin->plugin->deinit)

    (void)plugin->plugin->deinit(udff);

  if (udff)

    free(udff);

  return 0;

}