Addition of the module utilities functions

server/core/Makefile

@@ -57,7 +57,7 @@ LDFLAGS=-rdynamic -L$(LOGPATH) \
 SRCS= atomic.c buffer.c spinlock.c gateway.c \
 	gw_utils.c utils.c dcb.c load_utils.c session.c service.c server.c \
 	poll.c config.c users.c hashtable.c dbusers.c thread.c gwbitmask.c \
-	monitor.c adminusers.c secrets.c filter.c
+	monitor.c adminusers.c secrets.c filter.c modutil.c
 
 HDRS= ../include/atomic.h ../include/buffer.h ../include/dcb.h \
 	../include/gw.h ../modules/include/mysql_client_server_protocol.h \
@@ -65,7 +65,7 @@ HDRS= ../include/atomic.h ../include/buffer.h ../include/dcb.h \
 	../include/modules.h ../include/poll.h ../include/config.h \
 	../include/users.h ../include/hashtable.h ../include/gwbitmask.h \
 	../include/adminusers.h ../include/version.h ../include/maxscale.h \
-	../include/filter.h
+	../include/filter.h modutil.h
 
 OBJ=$(SRCS:.c=.o)
 

server/core/config.c

@@ -388,7 +388,7 @@ int			error_count = 0;
                                         obj->object)));
 				error_count++;
 			}
-			if (obj->element)
+			if (obj->element && options)
 			{
 				char *s = strtok(options, ",");
 				while (s)
@@ -397,6 +397,22 @@ int			error_count = 0;
 					s = strtok(NULL, ",");
 				}
 			}
+			if (obj->element)
+			{
+				CONFIG_PARAMETER *params = obj->parameters;
+				while (params)
+				{
+					if (strcmp(params->name, "module")
+						&& strcmp(params->name,
+							"options"))
+					{
+						filterAddParameter(obj->element,
+							params->name,
+							params->value);
+					}
+					params = params->next;
+				}
+			}
 		}
 		obj = obj->next;
 	}

server/core/filter.c

@@ -60,6 +60,8 @@ FILTER_DEF 	*filter;
 		return NULL;
 	filter->name = strdup(name);
 	filter->module = strdup(module);
+	filter->options = NULL;
+	filter->parameters = NULL;
 
 	spinlock_init(&filter->spin);
 
@@ -217,8 +219,6 @@ int	i;
 	spinlock_release(&filter_spin);
 }
 
-
-
 /**
  * Add a router option to a service
  *
@@ -249,6 +249,38 @@ int     i;
         spinlock_release(&filter->spin);
 }
 
+/**
+ * Add a router parameter to a service
+ *
+ * @param service       The service to add the router option to
+ * @param name		The parameter name
+ * @param value		The parameter value
+ */
+void
+filterAddParameter(FILTER_DEF *filter, char *name, char *value)
+{
+int     i;
+
+        spinlock_acquire(&filter->spin);
+        if (filter->parameters == NULL)
+        {
+                filter->parameters = (FILTER_PARAMETER **)calloc(2, sizeof(FILTER_PARAMETER *));
+		i = 0;
+        }
+        else
+        {
+                for (i = 0; filter->parameters[i]; i++)
+                        ;
+                filter->parameters = (FILTER_PARAMETER **)realloc(filter->options,
+                                (i + 2) * sizeof(FILTER_PARAMETER *));
+        }
+	filter->parameters[i] = (FILTER_PARAMETER *)calloc(1, sizeof(FILTER_PARAMETER));
+	filter->parameters[i]->name = strdup(name);
+	filter->parameters[i]->value = strdup(value);
+	filter->parameters[i+1] = NULL;
+        spinlock_release(&filter->spin);
+}
+
 DOWNSTREAM *
 filterApply(FILTER_DEF *filter, SESSION *session, DOWNSTREAM *downstream)
 {
@@ -264,7 +296,8 @@ DOWNSTREAM	*me;
 		}
 	}
 	if (filter->filter == NULL)
-		filter->filter = (filter->obj->createInstance)(filter->options);
+		filter->filter = (filter->obj->createInstance)(filter->options,
+					filter->parameters);
 	if ((me = (DOWNSTREAM *)calloc(1, sizeof(DOWNSTREAM))) == NULL)
 	{
 		return NULL;

server/core/modutil.c

@@ -0,0 +1,121 @@
+/*
+ * 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.c  - Implementation of useful routines for modules
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date		Who		Description
+ * 04/06/14	Mark Riddoch	Initial implementation
+ *
+ * @endverbatim
+ */
+#include <buffer.h>
+
+/**
+ * Check if a GWBUF structure is a MySQL COM_QUERY packet
+ *
+ * @param	buf	Buffer to check
+ * @return	True if GWBUF is a COM_QUERY packet
+ */
+int
+modutil_is_SQL(GWBUF *buf)
+{
+unsigned char	*ptr;
+
+	if (GWBUF_LENGTH(buf) < 5)
+		return 0;
+	ptr = GWBUF_DATA(buf);
+	return ptr[4] == 0x03;		// COM_QUERY
+}
+
+/**
+ * Extract the SQL portion of a COM_QUERY packet
+ *
+ * NB This sets *sql to point into the packet and does not
+ * allocate any new storage. The string pointed to by *sql is
+ * not NULL terminated.
+ *
+ * This routine is very simplistic and does not deal with SQL text
+ * that spans multiple buffers.
+ *
+ * @param	buf	The packet buffer
+ * @param	sql	Pointer that is set to point at the SQL data
+ * @param	length	Length of the SQL data
+ * @return	True if the packet is a COM_QUERY packet
+ */
+int
+modutil_extract_SQL(GWBUF *buf, char **sql, int *length)
+{
+char	*ptr;
+
+	if (!modutil_is_SQL(buf))
+		return 0;
+	ptr = GWBUF_DATA(buf);
+	*length = *ptr++;
+	*length += (*ptr++ << 8);
+	*length += (*ptr++ << 8);
+        ptr += 2;  // Skip sequence id	and COM_QUERY byte
+	*length = *length - 1;
+	*sql = ptr;
+}
+
+
+GWBUF *
+modutil_replace_SQL(GWBUF *orig, char *sql)
+{
+char	*ptr;
+int	length, newlength;
+GWBUF	*addition;
+
+	if (!modutil_is_SQL(orig))
+		return 0;
+	ptr = GWBUF_DATA(orig);
+	length = *ptr++;
+	length += (*ptr++ << 8);
+	length += (*ptr++ << 8);
+        ptr += 2;  // Skip sequence id	and COM_QUERY byte
+
+	newlength = strlen(sql);
+	if (length - 1 == newlength)
+	{
+		/* New SQL is the same length as old */
+		memcpy(ptr, sql, newlength);
+	}
+	else if (length - 1 > newlength)
+	{
+		/* New SQL is shorter */
+		memcpy(ptr, sql, newlength);
+		GWBUF_RTRIM(orig, (length - 1) - newlength);
+	}
+	else
+	{
+		memcpy(ptr, sql, length - 1);
+		addition = gwbuf_alloc(newlength - (length - 1));
+		memcpy(GWBUF_DATA(addition), &sql[length - 1], newlength - (length - 1));
+		ptr = GWBUF_DATA(orig);
+		*ptr++ = (newlength + 1) & 0xff;
+		*ptr++ = ((newlength + 1) >> 8) & 0xff;
+		*ptr++ = ((newlength + 1) >> 16) & 0xff;
+		orig->next = addition;
+	}
+
+	return orig;
+}

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.

server/modules/filter/qlafilter.c

@@ -32,6 +32,7 @@
 #include <fcntl.h>
 #include <filter.h>
 #include <modinfo.h>
+#include <modutil.h>
 #include <string.h>
 
 MODULE_INFO 	info = {
@@ -46,7 +47,7 @@ static char *version_str = "V1.0.0";
 /*
  * The filter entry points
  */
-static	FILTER	*createInstance(char **options);
+static	FILTER	*createInstance(char **options, FILTER_PARAMETER **);
 static	void	*newSession(FILTER *instance, SESSION *session);
 static	void 	closeSession(FILTER *instance, void *session);
 static	void 	freeSession(FILTER *instance, void *session);
@@ -135,7 +136,7 @@ GetModuleObject()
  * @return The instance data for this new instance
  */
 static	FILTER	*
-createInstance(char **options)
+createInstance(char **options, FILTER_PARAMETER **params)
 {
 QLA_INSTANCE	*my_instance;
 
@@ -178,7 +179,7 @@ QLA_SESSION	*my_session;
 				my_instance->sessions);
 		my_instance->sessions++;
 		my_session->fd = open(my_session->filename,
-					O_WRONLY|O_CREAT, 0666);
+					O_WRONLY|O_CREAT|O_TRUNC, 0666);
 	}
 
 	return my_session;
@@ -235,7 +236,7 @@ QLA_SESSION	*my_session = (QLA_SESSION *)session;
 /**
  * The routeQuery entry point. This is passed the query buffer
  * to which the filter should be applied. Once applied the
- * query shoudl normally be passed to the downstream component
+ * query should normally be passed to the downstream component
  * (filter or router) in the filter chain.
  *
  * @param instance	The filter instance data
@@ -246,18 +247,12 @@ static	int
 routeQuery(FILTER *instance, void *session, GWBUF *queue)
 {
 QLA_SESSION	*my_session = (QLA_SESSION *)session;
-unsigned char	*ptr;
+char	*ptr;
-unsigned int	length;
+int	length;
 
-	/* Find the text of the query and write to the file */
+	if (modutil_extract_SQL(queue, &ptr, &length))
-	ptr = GWBUF_DATA(queue);
-	length = *ptr++;
-	length += (*ptr++ << 8);
-	length += (*ptr++ << 8);
-	ptr++;	// Skip sequence id
-	if (*ptr++ == 0x03 && my_session->fd != -1)	// COM_QUERY
 	{
-		write(my_session->fd, ptr, length - 1);
+		write(my_session->fd, ptr, length);
 		write(my_session->fd, "\n", 1);
 	}
 

server/modules/filter/testfilter.c

@@ -18,6 +18,7 @@
 #include <stdio.h>
 #include <filter.h>
 #include <modinfo.h>
+#include <modutil.h>
 
 /**
  * testfilter.c - a very simple test filter.
@@ -38,7 +39,7 @@ MODULE_INFO 	info = {
 
 static char *version_str = "V1.0.0";
 
-static	FILTER	*createInstance(char **options);
+static	FILTER	*createInstance(char **options, FILTER_PARAMETER **params);
 static	void	*newSession(FILTER *instance, SESSION *session);
 static	void 	closeSession(FILTER *instance, void *session);
 static	void 	freeSession(FILTER *instance, void *session);
@@ -115,7 +116,7 @@ GetModuleObject()
  * @return The instance data for this new instance
  */
 static	FILTER	*
-createInstance(char **options)
+createInstance(char **options, FILTER_PARAMETER **params)
 {
 TEST_INSTANCE	*my_instance;
 
@@ -201,7 +202,8 @@ routeQuery(FILTER *instance, void *session, GWBUF *queue)
 {
 TEST_SESSION	*my_session = (TEST_SESSION *)session;
 
-	my_session->count++;
+	if (modutil_is_SQL(queue))
+		my_session->count++;
 	return my_session->down.routeQuery(my_session->down.instance,
 			my_session->down.session, queue);
 }