Addition of the module utilities functions

server/include/buffer.h

@@ -93,6 +93,8 @@ typedef struct gwbuf {
 /*< Consume a number of bytes in the buffer */
 #define GWBUF_CONSUME(b, bytes)	(b)->start += bytes
 
+#define GWBUF_RTRIM(b, bytes)	(b)->end -= bytes
+
 #define GWBUF_TYPE(b) (b)->gwbuf_type
 /*<
  * Function prototypes for the API to maniplate the buffers

server/include/filter.h

@@ -37,6 +37,15 @@
  * 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
@@ -60,7 +69,7 @@ typedef void *FILTER;
  * @see load_module
  */
 typedef struct filter_object {
-	FILTER	*(*createInstance)(char **options);
+	FILTER	*(*createInstance)(char **options, FILTER_PARAMETER **);
 	void	*(*newSession)(FILTER *instance, SESSION *session);
 	void 	(*closeSession)(FILTER *instance, void *fsession);
         void 	(*freeSession)(FILTER *instance, void *fsession);
@@ -75,7 +84,6 @@ typedef struct filter_object {
  * file modinfo.h.
  */
 #define FILTER_VERSION	{1, 0, 0}
-
 /**
  * The definition of a filter form the configuration file.
  * This is basically the link between a plugin to load and the
@@ -85,6 +93,8 @@ 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;
 	FILTER_OBJECT	*obj;
 	SPINLOCK	spin;
@@ -96,6 +106,7 @@ FILTER_DEF	*filter_alloc(char *, char *);
 void		filter_free(FILTER_DEF *);
 FILTER_DEF	*filter_find(char *);
 void		filterAddOption(FILTER_DEF *, char *);
+void		filterAddParameter(FILTER_DEF *, char *, char *);
 DOWNSTREAM	*filterApply(FILTER_DEF *, SESSION *, DOWNSTREAM *);
 void		dprintAllFilters(DCB *);
 void		dprintFilter(DCB *, FILTER_DEF *);

server/include/modutil.h

@@ -0,0 +1,36 @@
+#ifndef _MODUTIL_H
+#define _MODUTIL_H
+/*
+ * This file is distributed as part of MaxScale from SkySQL.  It 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.
+ *
+ * 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright SkySQL Ab 2014
+ */
+
+/**
+ * @file modutil.h A set of useful routines for module writers
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date		Who		Description
+ * 04/06/14	Mark Riddoch	Initial implementation
+ *
+ * @endverbatim
+ */
+#include <buffer.h>
+
+extern int	modutil_is_SQL(GWBUF *);
+extern int	modutil_extract_SQL(GWBUF *, char **, int *);
+#endif

server/include/session.h

@@ -74,6 +74,17 @@ typedef struct {
 				void *router_session, GWBUF *queue);
 } DOWNSTREAM;
 
+/**
+ * The upstream element in the filter chain. This may refer to
+ * another filter or to the protocol implementation.
+ */
+typedef struct {
+	void		*instance;
+	void		*session;
+	int		(*write)(void *, void *, GWBUF *);
+	int		(*error)(void *);
+} UPSTREAM;
+
 /**
  * Structure used to track the filter instances and sessions of the filters
  * that are in use within a session.