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/* Copyright (C) 2006 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#include <drizzled/mysql_priv.h>
#include <stdlib.h>
#include <ctype.h>
#include <drizzled/plugin.h>
bool udf_init_hello_world(UDF_INIT *initid, UDF_ARGS *args, char *message)
{
/* this is how to fail */
if (args->arg_count != 0) {
strncpy(message, "Too many arguments", MYSQL_ERRMSG_SIZE);
return 1;
}
/* initid->ptr keeps state for between udf_init_foo and udf_deinit_foo */
initid->ptr= NULL;
return 0;
}
char *udf_doit_hello_world(UDF_INIT *initid, UDF_ARGS *args, char *result,
unsigned long *length, char *is_null, char *error)
{
/* We don't use these, so void them out */
(void)initid;
(void)args;
/* "result" is preallocated 255 bytes for me, if i want to use it */
strncpy(result, "Hello, world!", 255);
/* if set to 255 or less, MySQL treats the result as a varchar
if set to greater than 255, MySQL treats the result as a blob */
*length= strlen("Hello, world!");
/* is_null is already zero, this is a demonstration */
*is_null= 0;
/* error is already zero, this is a demonstration */
*error= 0;
return result;
}
void udf_deinit_hello_world(UDF_INIT *initid)
{
/* We don't use this, so void it out */
(void)initid;
/* if we allocated initid->ptr, free it here */
return;
}
static int hello_world_plugin_init(void *p)
{
udf_func *udff= (udf_func *) p;
udff->name.str= (char *)"hello_world";
udff->name.length= strlen("hello_world");
udff->type= UDFTYPE_FUNCTION;
udff->returns= STRING_RESULT;
udff->func_init= udf_init_hello_world;
udff->func_deinit= udf_deinit_hello_world;
udff->func= (Udf_func_any) udf_doit_hello_world;
return 0;
}
static int hello_world_plugin_deinit(void *p)
{
/* We don't use this, so void it out */
(void)p;
/* There is nothing to de-init here, but if
* something is needed from the udf_func, it
* can be had from p with:
* udf_func *udff = (udf_func *) p;
*/
return 0;
}
mysql_declare_plugin(hello_world)
{
MYSQL_UDF_PLUGIN,
"hello_world",
"1.0",
"Mark Atwood",
"Hello, world!",
PLUGIN_LICENSE_GPL,
hello_world_plugin_init, /* Plugin Init */
hello_world_plugin_deinit, /* Plugin Deinit */
NULL, /* status variables */
NULL, /* system variables */
NULL /* config options */
}
mysql_declare_plugin_end;
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