Files
MaxScale/include/maxscale/filter.h
Johan Wikman 1a978be6b6 Cleanup header files
- All now include maxscale/cdefs.h as the very first file.
- MXS_[BEGIN|END]_DECLS added to all C-headers.
  Strictly speaking not necessary for private headers, but
  does not hurt either.
- Include guards moved to the very top of the file.
- #pragma once added.
2016-10-14 11:54:37 +03:00

127 lines
4.3 KiB
C

#pragma once
#ifndef _MAXSCALE_FILTER_H
#define _MAXSCALE_FILTER_H
/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl.
*
* Change Date: 2019-07-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
/**
* @file filter.h - The filter interface mechanisms
*
* Revision History
*
* Date Who Description
* 27/05/2014 Mark Riddoch Initial implementation
*
*/
#include <maxscale/cdefs.h>
#include <maxscale/dcb.h>
#include <maxscale/session.h>
#include <maxscale/buffer.h>
#include <stdint.h>
MXS_BEGIN_DECLS
/**
* The FILTER handle points to module specific data, so the best we can do
* is to make it a void * externally.
*/
typedef void *FILTER;
/**
* The structure used to pass name, value pairs to the filter instances
*/
typedef struct
{
char *name; /**< Name of the parameter */
char *value; /**< Value of the parameter */
} FILTER_PARAMETER;
/**
* @verbatim
* The "module object" structure for a query router module
*
* The entry points are:
* createInstance Called by the service to create a new
* instance of the filter
* newSession Called to create a new user session
* within the filter
* closeSession Called when a session is closed
* freeSession Called when a session is freed
* setDownstream Sets the downstream component of the
* filter pipline
* routeQuery Called on each query that requires
* routing
* clientReply Called for each reply packet
* diagnostics Called to force the filter to print
* diagnostic output
*
* @endverbatim
*
* @see load_module
*/
typedef struct filter_object
{
FILTER *(*createInstance)(const char *name,
char **options,
FILTER_PARAMETER **params);
void *(*newSession)(FILTER *instance, SESSION *session);
void (*closeSession)(FILTER *instance, void *fsession);
void (*freeSession)(FILTER *instance, void *fsession);
void (*setDownstream)(FILTER *instance, void *fsession, DOWNSTREAM *downstream);
void (*setUpstream)(FILTER *instance, void *fsession, UPSTREAM *downstream);
int (*routeQuery)(FILTER *instance, void *fsession, GWBUF *queue);
int (*clientReply)(FILTER *instance, void *fsession, GWBUF *queue);
void (*diagnostics)(FILTER *instance, void *fsession, DCB *dcb);
} FILTER_OBJECT;
/**
* The filter API version. If the FILTER_OBJECT structure or the filter API
* is changed these values must be updated in line with the rules in the
* file modinfo.h.
*/
#define FILTER_VERSION {2, 1, 0}
/**
* The definition of a filter from the configuration file.
* This is basically the link between a plugin to load and the
* optons to pass to that plugin.
*/
typedef struct filter_def
{
char *name; /**< The Filter name */
char *module; /**< The module to load */
char **options; /**< The options set for this filter */
FILTER_PARAMETER **parameters; /**< The filter parameters */
FILTER filter; /**< The runtime filter */
FILTER_OBJECT *obj; /**< The "MODULE_OBJECT" for the filter */
SPINLOCK spin; /**< Spinlock to protect the filter definition */
struct filter_def *next; /**< Next filter in the chain of all filters */
} FILTER_DEF;
FILTER_DEF *filter_alloc(char *, char *);
void filter_free(FILTER_DEF *);
bool filter_load(FILTER_DEF* filter);
FILTER_DEF *filter_find(char *);
void filterAddOption(FILTER_DEF *, char *);
void filterAddParameter(FILTER_DEF *, char *, char *);
DOWNSTREAM *filterApply(FILTER_DEF *, SESSION *, DOWNSTREAM *);
UPSTREAM *filterUpstream(FILTER_DEF *, void *, UPSTREAM *);
int filter_standard_parameter(char *);
void dprintAllFilters(DCB *);
void dprintFilter(DCB *, FILTER_DEF *);
void dListFilters(DCB *);
MXS_END_DECLS
#endif