A number of updates to do with service startup

Telnet protocol support

Debug cli

README

@@ -22,4 +22,35 @@ function pointers. This structured is called the "module object".
 
 The code that routes the queries to the database servers is also loaed
 as external shared objects and are referred to as routing modules.
+
+\section Building Building the Gateway
+
+The gateway is designed to be built using make. Simply run the make command
+from the top level and it will build all the components ofthe system.
+
+Other make targets are available
+
+install - Installs the binary and the modules in the location defined by the
+make variable DEST
+
+ctags - Build tags files for the vi editor
+
+documentation - Build the doxygen documentation
+
+depend - Update the dependencies used by the makefiles
+
+\section Running  Running the Gateway
+
+The gateway consists of a core executable and a number of modules that implement
+the different protocols and routing algorithms. These modules are built as
+shared objects that are loaded on demand. In order for the gateway to find these
+modules it will search using a predescribed search path. The rules are:
+
+1. Look in the current directory for the module
+
+2. Look in $GATEWAY_HOME/modules
+
+3. Look in /usr/local/skysql/gateway/modules
+
+
 */

core/Makefile

@@ -21,7 +21,7 @@
 # 17/06/13	Mark Riddoch		Addition of dependency generation
 
 CC=cc
-CFLAGS=-c -I/usr/include -I../include -Wall
+CFLAGS=-c -I/usr/include -I../include -Wall -g
 LDFLAGS=-rdynamic
 SRCS= atomic.c buffer.c spinlock.c gateway.c gateway_mysql_protocol.c gw_utils.c \
 	utils.c dcb.c load_utils.c session.c service.c server.c

core/dcb.c

@@ -378,6 +378,38 @@ DCB	*dcb;
 	spinlock_release(dcbspin);
 }
 
+
+/**
+ * Diagnostic to print all DCB allocated in the system
+ *
+ */
+void dprintAllDCBs(DCB *pdcb)
+{
+DCB	*dcb;
+
+	if (dcbspin == NULL)
+	{
+		if ((dcbspin = malloc(sizeof(SPINLOCK))) == NULL)
+			return;
+		spinlock_init(dcbspin);
+	}
+	spinlock_acquire(dcbspin);
+	dcb = allDCBs;
+	while (dcb)
+	{
+		dcb_printf(pdcb, "DCB: 0x%p\n", (void *)dcb);
+		dcb_printf(pdcb, "\tDCB state: %s\n", gw_dcb_state2string(dcb->state));
+		dcb_printf(pdcb, "\tQueued write data: %d\n", gwbuf_length(dcb->writeq));
+		dcb_printf(pdcb, "\tStatistics:\n");
+		dcb_printf(pdcb, "\t\tNo. of Reads: %d\n", dcb->stats.n_reads);
+		dcb_printf(pdcb, "\t\tNo. of Writes: %d\n", dcb->stats.n_writes);
+		dcb_printf(pdcb, "\t\tNo. of Buffered Writes: %d\n", dcb->stats.n_buffered);
+		dcb_printf(pdcb, "\t\tNo. of Accepts: %d\n", dcb->stats.n_accepts);
+		dcb = dcb->next;
+	}
+	spinlock_release(dcbspin);
+}
+
 /**
  * Return a string representation of a DCB state.
  *

core/depend.mk

@@ -285,7 +285,10 @@ load_utils.o: load_utils.c /usr/include/sys/param.h \
  /usr/include/unistd.h /usr/include/bits/posix_opt.h \
  /usr/include/bits/environments.h /usr/include/bits/confname.h \
  /usr/include/getopt.h /usr/include/string.h /usr/include/xlocale.h \
- /usr/include/dlfcn.h /usr/include/bits/dlfcn.h ../include/modules.h
+ /usr/include/dlfcn.h /usr/include/bits/dlfcn.h ../include/modules.h \
+ ../include/dcb.h ../include/spinlock.h ../include/thread.h \
+ /usr/include/pthread.h /usr/include/sched.h /usr/include/bits/sched.h \
+ /usr/include/bits/setjmp.h ../include/buffer.h
 session.o: session.c /usr/include/stdio.h /usr/include/features.h \
  /usr/include/sys/cdefs.h /usr/include/bits/wordsize.h \
  /usr/include/gnu/stubs.h /usr/include/gnu/stubs-64.h \
@@ -347,4 +350,4 @@ server.o: server.c /usr/include/stdio.h /usr/include/features.h \
  /usr/include/string.h /usr/include/xlocale.h ../include/session.h \
  ../include/server.h ../include/spinlock.h ../include/thread.h \
  /usr/include/pthread.h /usr/include/sched.h /usr/include/bits/sched.h \
- /usr/include/bits/setjmp.h
+ /usr/include/bits/setjmp.h ../include/dcb.h ../include/buffer.h

core/gateway.c

@@ -176,7 +176,7 @@ struct epoll_event	ev;
 int			nfds;
 int			n;
 unsigned short		port = 4406;
-SERVICE			*service;
+SERVICE			*service1, *service2;
 SERVER			*server1, *server2, *server3;
 
 	for (n = 0; n < argc; n++)
@@ -185,6 +185,11 @@ SERVER			*server1, *server2, *server3;
 		{
 			port = atoi(&argv[n][2]);
 		}
+		if (strcmp(argv[n], "-d") == 0)
+		{
+			// Debug mode
+			daemon_mode = 0;
+		}
 	}
 
 	/*
@@ -193,16 +198,21 @@ SERVER			*server1, *server2, *server3;
 	 * will build a static configuration here
 	 */
 
-	if ((service = service_alloc("Test Service", "readconnroute")) == NULL)
+	if ((service1 = service_alloc("Test Service", "readconnroute")) == NULL)
 		exit(1);
-	serviceAddProtocol(service, "MySQLClient", port);
+	serviceAddProtocol(service1, "MySQLClient", port);
 
 	server1 = server_alloc("127.0.0.1", "MySQLBackend", 3306);
 	server2 = server_alloc("127.0.0.1", "MySQLBackend", 3307);
 	server3 = server_alloc("127.0.0.1", "MySQLBackend", 3308);
-	serviceAddBackend(service, server1);
+	serviceAddBackend(service1, server1);
-	serviceAddBackend(service, server2);
+	serviceAddBackend(service1, server2);
-	serviceAddBackend(service, server3);
+	serviceAddBackend(service1, server3);
+
+
+	if ((service2 = service_alloc("Debug Service", "debugcli")) == NULL)
+		exit(1);
+	serviceAddProtocol(service2, "telnetd", 4442);
 
 	fprintf(stderr, "(C) SkySQL Ab 2013\n"); 
 
@@ -246,7 +256,8 @@ SERVER			*server1, *server2, *server3;
 	/*
 	 * Start the service that was created above
 	 */
-	serviceStart(service, epollfd);
+	serviceStart(service1, epollfd);
+	serviceStart(service2, epollfd);
 
 	fprintf(stderr, ">> GATEWAY epoll maxevents is %i\n", MAX_EVENTS);
 
@@ -259,7 +270,7 @@ SERVER			*server1, *server2, *server3;
 	5. bind
 	6. epoll add event
 	*/
-	MySQLListener(epollfd, port);
+	// MySQLListener(epollfd, port);
 
 	// event loop for all the descriptors added via epoll_ctl
 	while (1) {

core/load_utils.c

@@ -246,3 +246,22 @@ MODULES	*ptr = registered;
 		ptr = ptr->next;
 	}
 }
+
+/**
+ * Print Modules to a DCB
+ *
+ * Diagnostic routine to display all the loaded modules
+ */
+void
+dprintAllModules(DCB *dcb)
+{
+MODULES	*ptr = registered;
+
+	dcb_printf(dcb, "%-15s | %-10s | Version\n", "Module Name", "Module Type");
+	dcb_printf(dcb, "-----------------------------------------------------\n");
+	while (ptr)
+	{
+		dcb_printf(dcb, "%-15s | %-10s | %s\n", ptr->module, ptr->type, ptr->version);
+		ptr = ptr->next;
+	}
+}

core/server.c

@@ -33,6 +33,7 @@
 #include <session.h>
 #include <server.h>
 #include <spinlock.h>
+#include <dcb.h>
 
 static SPINLOCK	server_spin = SPINLOCK_INIT;
 static SERVER	*allServers = NULL;
@@ -139,3 +140,27 @@ SERVER	*ptr;
 	}
 	spinlock_release(&server_spin);
 }
+
+/**
+ * Print all servers to a DCB
+ *
+ * Designed to be called within a debugger session in order
+ * to display all active servers within the gateway
+ */
+void
+dprintAllServers(DCB *dcb)
+{
+SERVER	*ptr;
+
+	spinlock_acquire(&server_spin);
+	ptr = allServers;
+	while (ptr)
+	{
+		dcb_printf(dcb, "Server %p\n", ptr);
+		dcb_printf(dcb, "\tServer:		%s\n", ptr->name);
+		dcb_printf(dcb, "\tProtocol:		%s\n", ptr->protocol);
+		dcb_printf(dcb, "\tPort:			%d\n", ptr->port);
+		ptr = ptr->next;
+	}
+	spinlock_release(&server_spin);
+}

core/service.c

@@ -36,6 +36,7 @@
 #include <router.h>
 #include <spinlock.h>
 #include <modules.h>
+#include <dcb.h>
 
 static SPINLOCK	service_spin = SPINLOCK_INIT;
 static SERVICE	*allServices = NULL;
@@ -96,6 +97,8 @@ int		listeners = 0;
 char		config_bind[40];
 GWPROTOCOL	*funcs;
 
+	service->router_instance = service->router->createInstance(service);
+
 	port = service->ports;
 	while (port)
 	{
@@ -111,15 +114,16 @@ GWPROTOCOL	*funcs;
 		memcpy(&(port->listener->func), funcs, sizeof(GWPROTOCOL));
 		port->listener->session = NULL;
 		sprintf(config_bind, "0.0.0.0:%d", port->port);
-		if (port->listener->func.listen(efd, config_bind))
+		if (port->listener->func.listen(port->listener, efd, config_bind))
 			listeners++;
+		port->listener->session = session_alloc(service, port->listener);
+		port->listener->session->state = SESSION_STATE_LISTENER;
+
+		port = port->next;
 	}
-	port->listener->session = session_alloc(service, port->listener);
-	port->listener->session->state = SESSION_STATE_LISTENER;
 	if (listeners)
 		service->stats.started = time(0);
 
-	service->router_instance = service->router->createInstance(service);
 	return listeners;
 }
 
@@ -247,3 +251,39 @@ SERVICE	*ptr;
 	}
 	spinlock_release(&service_spin);
 }
+
+/**
+ * Print all services to a DCB
+ *
+ * Designed to be called within a debugger session in order
+ * to display all active services within the gateway
+ */
+void
+dprintAllServices(DCB *dcb)
+{
+SERVICE	*ptr;
+
+	spinlock_acquire(&service_spin);
+	ptr = allServices;
+	while (ptr)
+	{
+		SERVER	*server = ptr->databases;
+		dcb_printf(dcb, "Service %p\n", ptr);
+		dcb_printf(dcb, "\tService:		%s\n", ptr->name);
+		dcb_printf(dcb, "\tRouter:		%s (%p)\n", ptr->routerModule,
+										ptr->router);
+		dcb_printf(dcb, "\tStarted:		%s",
+						asctime(localtime(&ptr->stats.started)));
+		dcb_printf(dcb, "\tBackend databases\n");
+		while (server)
+		{
+			dcb_printf(dcb, "\t\t%s:%d  %s\n", server->name, server->port,
+									server->protocol);
+			server = server->next;
+		}
+		dcb_printf(dcb, "\tTotal connections:	%d\n", ptr->stats.n_sessions);
+		dcb_printf(dcb, "\tCurrently connected:	%d\n", ptr->stats.n_current);
+		ptr = ptr->next;
+	}
+	spinlock_release(&service_spin);
+}

core/session.c

@@ -146,3 +146,27 @@ SESSION	*ptr;
 	}
 	spinlock_release(&session_spin);
 }
+
+/**
+ * Print all sessions to a DCB
+ *
+ * Designed to be called within a debugger session in order
+ * to display all active sessions within the gateway
+ */
+void
+dprintAllSessions(DCB *dcb)
+{
+SESSION	*ptr;
+
+	spinlock_acquire(&session_spin);
+	ptr = allSessions;
+	while (ptr)
+	{
+		dcb_printf(dcb, "Session %p\n", ptr);
+		dcb_printf(dcb, "\tService:	%s (%p)\n", ptr->service->name, ptr->service);
+		dcb_printf(dcb, "\tClient DCB:	%p\n", ptr->client);
+		dcb_printf(dcb, "\tConnected:	%s", asctime(localtime(&ptr->stats.connect)));
+		ptr = ptr->next;
+	}
+	spinlock_release(&session_spin);
+}

include/dcb.h

@@ -73,7 +73,7 @@ typedef struct gw_protocol {
 	int		(*accept)(struct dcb *, int);
 	int		(*connect)(struct server *, struct session *, int);
 	int		(*close)(struct dcb *, int);
-	int		(*listen)(int, char *);
+	int		(*listen)(struct dcb *, int, char *);
 } GWPROTOCOL;
 
 /**
@@ -133,6 +133,7 @@ extern int		dcb_write(DCB *, GWBUF *);	/* Generic write routine */
 extern int		dcb_drain_writeq(DCB *);	/* Generic write routine */
 extern void		printAllDCBs();			/* Debug to print all DCB in the system */
 extern void		printDCB(DCB *);		/* Debug print routine */
+extern void		dprintAllDCBs(DCB *);		/* Debug to print all DCB in the system */
 extern const char 	*gw_dcb_state2string(int);	/* DCB state to string */
 extern void		dcb_printf(DCB *, const char *, ...);	/* DCB version of printf */
 

include/modules.h

@@ -17,6 +17,7 @@
  *
  * Copyright SkySQL Ab 2013
  */
+#include <dcb.h>
 
 /**
  * @file modules.h	Utilities for loading modules
@@ -51,4 +52,5 @@ typedef struct modules {
 extern	void 	*load_module(const char *module, const char *type);
 extern	void	unload_module(const char *module);
 extern	void	printModules();
+extern	void	dprintAllModules(DCB *);
 #endif

include/server.h

@@ -59,4 +59,5 @@ extern SERVER	*server_alloc(char *, char *, unsigned short);
 extern int	server_free(SERVER *);
 extern void	printServer(SERVER *);
 extern void	printAllServers();
+extern void	dprintAllServers();
 #endif

include/service.h

@@ -98,4 +98,5 @@ extern	void	serviceAddBackend(SERVICE *, SERVER *);
 extern	int	serviceStart(SERVICE *, int);
 extern	void	printService(SERVICE *);
 extern	void	printAllServices();
+extern	void	dprintAllServices(DCB *);
 #endif

include/session.h

@@ -70,4 +70,5 @@ extern SESSION	*session_alloc(struct service *, struct dcb *);
 extern void	session_free(SESSION *);
 extern void	printAllSessions();
 extern void	printSession(SESSION *);
+extern void	dprintAllSessions(struct dcb *);
 #endif

modules/include/debugcli.h

@@ -0,0 +1,60 @@
+#ifndef _DEBUGCLI_H
+#define _DEBUGCLI_H
+/*
+ * This file is distributed as part of the SkySQL Gateway.  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 2013
+ */
+#include <service.h>
+#include <session.h>
+#include <spinlock.h>
+
+/**
+ * @file debugcli.h The debug interface to the gateway
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date		Who		Description
+ * 18/06/13	Mark Riddoch	Initial implementation
+ *
+ * @endverbatim
+ */
+struct cli_session;
+
+/**
+ * The CLI_INSTANCE structure. There is one instane of the CLI "router" for
+ * each service that uses the CLI.
+ */
+typedef struct cli_instance {
+	SPINLOCK	lock;		/**< The instance spinlock */
+	SERVICE		*service;	/**< The debug cli service */
+	struct cli_session
+			*sessions;	/**< Linked list of sessions within this instance */
+	struct cli_instance
+			*next;		/**< The next pointer for the list of instances */
+} CLI_INSTANCE;
+
+/**
+ * The CLI_SESSION structure. As CLI_SESSION is created for each user that logs into
+ * the DEBUG CLI.
+ */
+typedef struct cli_session {
+	char		cmdbuf[80];	/**< The command buffer used to build up user commands */
+	SESSION		*session;	/**< The gateway session */
+	struct cli_session
+			*next;		/**< The next pointer for the list of sessions */
+} CLI_SESSION;
+#endif

modules/protocol/Makefile

@@ -20,16 +20,18 @@
 # 17/06/2013	Massimiliano Pinto	Added mysql_common top both libraries
 
 CC=cc
-CFLAGS=-c -fPIC -I/usr/include -I../include -I../../include
+CFLAGS=-c -fPIC -I/usr/include -I../include -I../../include -g
 LDFLAGS=-shared
 MYSQLCLIENTSRCS=mysql_client.c mysql_common.c
 MYSQLCLIENTOBJ=$(MYSQLCLIENTSRCS:.c=.o)
 MYSQLBACKENDSRCS=mysql_backend.c mysql_common.c
 MYSQLBACKENDOBJ=$(MYSQLBACKENDSRCS:.c=.o)
+TELNETDSRCS=telnetd.c
+TELNETDOBJ=$(TELNETDSRCS:.c=.o)
 SRCS=$(MYSQLCLIENTSRCS) $(MYSQLBACKENDSRCS)
 OBJ=$(SRCS:.c=.o)
 LIBS=
-MODULES=libMySQLClient.so libMySQLBackend.so
+MODULES=libMySQLClient.so libMySQLBackend.so libtelnetd.so
 
 all:	$(MODULES)
 
@@ -39,11 +41,14 @@ libMySQLClient.so: $(MYSQLCLIENTOBJ)
 libMySQLBackend.so: $(MYSQLBACKENDOBJ)
 	$(CC) $(LDFLAGS) $(MYSQLBACKENDOBJ) $(LIBS) -o $@
 
+libtelnetd.so: $(TELNETDOBJ)
+	$(CC) $(LDFLAGS) $(TELNETDOBJ) $(LIBS) -o $@
+
 .c.o:
 	$(CC) $(CFLAGS) $< -o $@
 
 clean:
-	rm -f $(OBJ) libMySQLClient.so libMySQLBackend.so
+	rm -f $(OBJ) $(MODULES)
 
 tags:
 	ctags $(SRCS) $(HDRS)

modules/protocol/mysql_client.c

@@ -33,7 +33,7 @@
 static char *version_str = "V1.0.0";
 
 static int gw_MySQLAccept(DCB *listener, int efd);
-static int gw_MySQLListener(int epfd, char *config_bind);
+static int gw_MySQLListener(DCB *listener, int epfd, char *config_bind);
 static int gw_read_client_event(DCB* dcb, int epfd);
 static int gw_write_client_event(DCB *dcb, int epfd);
 static int gw_MySQLWrite_client(DCB *dcb, GWBUF *queue);
@@ -904,8 +904,7 @@ int gw_write_client_event(DCB *dcb, int epfd) {
 ///
 // set listener for mysql protocol
 ///
-int gw_MySQLListener(int epfd, char *config_bind) {
+int gw_MySQLListener(DCB *listener, int epfd, char *config_bind) {
-	DCB *listener;
 	int l_so;
 	int fl;
 	struct sockaddr_in serv_addr;
@@ -921,9 +920,6 @@ int gw_MySQLListener(int epfd, char *config_bind) {
 	// this gateway, as default, will bind on port 4404 for localhost only
 	(config_bind != NULL) ? (bind_address_and_port = config_bind) : (bind_address_and_port = "127.0.0.1:4406");
 
-	listener = (DCB *) calloc(1, sizeof(DCB));
-
-	listener->state = DCB_STATE_ALLOC;
 	listener->fd = -1;
 	
         memset(&serv_addr, 0, sizeof serv_addr);

modules/protocol/telnetd.c

@@ -16,6 +16,7 @@
  * Copyright SkySQL Ab 2013
  */
 #include <stdio.h>
+#include <string.h>
 #include <dcb.h>
 #include <buffer.h>
 #include <service.h>
@@ -26,6 +27,7 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <router.h>
 
 /**
  * @file telnetd.c - telnet daemon protocol module
@@ -56,7 +58,7 @@ static int telnetd_error(DCB *dcb, int event);
 static int telnetd_hangup(DCB *dcb, int event);
 static int telnetd_accept(DCB *dcb, int event);
 static int telnetd_close(DCB *dcb, int event);
-static int telnetd_listen(DCB *dcb, int event);
+static int telnetd_listen(DCB *dcb, int efd, char *config);
 
 /**
  * The "module object" for the telnetd protocol module.
@@ -122,7 +124,7 @@ int		n;
 GWBUF		*head = NULL;
 SESSION		*session = dcb->session;
 ROUTER_OBJECT	*router = session->service->router;
-ROUTER		*router_instanc = session->service->router_instance;
+ROUTER		*router_instance = session->service->router_instance;
 void		*rsession = session->router_session;
 
 	if ((n = dcb_read(dcb, &head)) != -1)
@@ -143,7 +145,7 @@ void		*rsession = session->router_session;
 static int
 telnetd_write_event(DCB *dcb, int epfd)
 {
-	int dcb_drain_writeq(dcb);
+	return dcb_drain_writeq(dcb);
 }
 
 /**
@@ -188,10 +190,10 @@ telnetd_hangup(DCB *dcb, int event)
  * socket for the protocol.
  *
  * @param dcb	The descriptor control block
- * @param event	The epoll descriptor
+ * @param efd	The epoll descriptor
  */
 static int
-telnetd_accept(DCB *dcb, int event)
+telnetd_accept(DCB *dcb, int efd)
 {
 int	n_connect = 0;
 
@@ -210,14 +212,14 @@ int	n_connect = 0;
 			atomic_add(&dcb->stats.n_accepts, 1);
 			client = alloc_dcb();
 			client->fd = so;
-			memcpy(&client->func, MyObject, sizeof(GWPROTOCOL));
+			memcpy(&client->func, &MyObject, sizeof(GWPROTOCOL));
-			client->session = session_alloc(listener->service, client);
+			client->session = session_alloc(dcb->session->service, client);
 
 			ee.events = EPOLLIN | EPOLLOUT | EPOLLET;
 			ee.data.ptr = client;
 			client->state = DCB_STATE_IDLE;
 
-			if (epoll_ctl(efd, EPOLL_CTL_ADD, c_sock, &ee) == -1)
+			if (epoll_ctl(efd, EPOLL_CTL_ADD, so, &ee) == -1)
 			{
 				return n_connect;
 			}
@@ -249,20 +251,15 @@ telnetd_close(DCB *dcb, int event)
  * @param	config		Configuration (ip:port)
  */
 static int
-telnetd_listen(int efd, char *config)
+telnetd_listen(DCB *listener, int efd, char *config)
 {
-DCB			*listener;
 struct sockaddr_in	addr;
 char			*port;
 struct epoll_event	ev;
-int			one;
+int			one = 1;
+short			pnum;
 
-	if ((listener = dcb_alloc()) == NULL)
+	memcpy(&listener->func, &MyObject, sizeof(GWPROTOCOL));
-	{
-		return 0;
-	}
-
-	memcpy(&listener->func, MyObject, sizeof(GWPROTOCOL));
 
 	port = strrchr(config, ':');
 	if (port)
@@ -272,7 +269,9 @@ int			one;
 
 	addr.sin_family = AF_INET;
 	addr.sin_addr.s_addr = htonl(INADDR_ANY);
-	addr.sin_port = htons(port);
+	pnum = atoi(port);
+	addr.sin_port = htons(pnum);
+printf("telnetd listen on port %d from %s from %s\n", pnum, port, config);
 
 	if ((listener->fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
 	{
@@ -283,8 +282,8 @@ int			one;
 	setsockopt(listener->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof(one));
         // set NONBLOCKING mode
         setnonblocking(listener->fd);
-        bind address and port
+        // bind address and port
-        if (bind(listener->fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
+        if (bind(listener->fd, (struct sockaddr *)&addr, sizeof(addr)) < 0)
 	{
         	return 0;
 	}
@@ -294,7 +293,7 @@ int			one;
 
 	ev.events = EPOLLIN;
         ev.data.ptr = listener;
-        if (epoll_ctl(epfd, EPOLL_CTL_ADD, l_so, &ev) == -1)
+        if (epoll_ctl(efd, EPOLL_CTL_ADD, listener->fd, &ev) == -1)
 	{
 		return 0;
 	}

modules/routing/Makefile

@@ -19,16 +19,18 @@
 # 13/06/13	Mark Riddoch		Initial routing module development
 
 CC=cc
-CFLAGS=-c -fPIC -I/usr/include -I../include -I../../include -Wall
+CFLAGS=-c -fPIC -I/usr/include -I../include -I../../include -Wall -g
 LDFLAGS=-shared
 TESTSRCS=testroute.c
 TESTOBJ=$(TESTSRCS:.c=.o)
 READCONSRCS=readconnroute.c
 READCONOBJ=$(READCONSRCS:.c=.o)
+DEBUGSRCS=debugcli.c
+DEBUGCLIOBJ=$(DEBUGSRCS:.c=.o)
 SRCS=$(TESTSRCS) $(READCONSRCS)
 OBJ=$(SRCS:.c=.o)
 LIBS=-lssl
-MODULES=libtestroute.so libreadconnroute.so
+MODULES=libtestroute.so libreadconnroute.so libdebugcli.so
 
 all:	$(MODULES)
 
@@ -38,11 +40,14 @@ libtestroute.so: $(TESTOBJ)
 libreadconnroute.so: $(READCONOBJ)
 	$(CC) $(LDFLAGS) $(READCONOBJ) $(LIBS) -o $@
 
+libdebugcli.so: $(DEBUGCLIOBJ)
+	$(CC) $(LDFLAGS) $(DEBUGCLIOBJ) $(LIBS) -o $@
+
 .c.o:
 	$(CC) $(CFLAGS) $< -o $@
 
 clean:
-	rm -f $(OBJ) libtestroute.so
+	rm -f $(OBJ) $(MODULES)
 
 tags:
 	ctags $(SRCS) $(HDRS)

modules/routing/debugcli.c

@@ -0,0 +1,272 @@
+/*
+ * This file is distributed as part of the SkySQL Gateway.  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 2013
+ */
+
+/**
+ * @file debugcli.c - A "routing module" that in fact merely gives
+ * access to debug commands within the gateway
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date		Who		Description
+ * 18/06/13	Mark Riddoch	Initial implementation
+ *
+ * @endverbatim
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <service.h>
+#include <session.h>
+#include <router.h>
+#include <modules.h>
+#include <atomic.h>
+#include <spinlock.h>
+#include <dcb.h>
+#include <debugcli.h>
+
+static char *version_str = "V1.0.0";
+
+/* The router entry points */
+static	ROUTER	*createInstance(SERVICE *service);
+static	void	*newSession(ROUTER *instance, SESSION *session);
+static	void 	closeSession(ROUTER *instance, void *router_session);
+static	int	execute(ROUTER *instance, void *router_session, GWBUF *queue);
+
+/** The module object definition */
+static ROUTER_OBJECT MyObject = { createInstance, newSession, closeSession, execute };
+
+static void execute_cmd(CLI_SESSION *cli);
+
+static SPINLOCK		instlock;
+static CLI_INSTANCE	*instances;
+
+/**
+ * Implementation of the mandatory version entry point
+ *
+ * @return version string of the module
+ */
+char *
+version()
+{
+	return version_str;
+}
+
+/**
+ * The module initialisation routine, called when the module
+ * is first loaded.
+ */
+void
+ModuleInit()
+{
+	fprintf(stderr, "Initial debug router module.\n");
+	spinlock_init(&instlock);
+	instances = NULL;
+}
+
+/**
+ * The module entry point routine. It is this routine that
+ * must populate the structure that is referred to as the
+ * "module object", this is a structure with the set of
+ * external entry points for this module.
+ *
+ * @return The module object
+ */
+ROUTER_OBJECT *
+GetModuleObject()
+{
+	fprintf(stderr, "Returing debug router module object.\n");
+	return &MyObject;
+}
+
+/**
+ * Create an instance of the router for a particular service
+ * within the gateway.
+ * 
+ * @param service	The service this router is being create for
+ *
+ * @return The instance data for this new instance
+ */
+static	ROUTER	*
+createInstance(SERVICE *service)
+{
+CLI_INSTANCE	*inst;
+
+	if ((inst = malloc(sizeof(CLI_INSTANCE))) == NULL)
+		return NULL;
+
+	inst->service = service;
+	spinlock_init(&inst->lock);
+	inst->sessions = NULL;
+
+
+	/*
+	 * We have completed the creation of the instance data, so now
+	 * insert this router instance into the linked list of routers
+	 * that have been created with this module.
+	 */
+	spinlock_acquire(&instlock);
+	inst->next = instances;
+	instances = inst;
+	spinlock_release(&instlock);
+
+	return (ROUTER *)inst;
+}
+
+/**
+ * Associate a new session with this instance of the router.
+ *
+ * @param instance	The router instance data
+ * @param session	The session itself
+ * @return Session specific data for this session
+ */
+static	void	*
+newSession(ROUTER *instance, SESSION *session)
+{
+CLI_INSTANCE	*inst = (CLI_INSTANCE *)instance;
+CLI_SESSION	*client;
+
+	if ((client = (CLI_SESSION *)malloc(sizeof(CLI_SESSION))) == NULL)
+	{
+		return NULL;
+	}
+	client->session = session;
+
+	memset(client->cmdbuf, 80, 0);
+
+	spinlock_acquire(&inst->lock);
+	client->next = inst->sessions;
+	inst->sessions = client;
+	spinlock_release(&inst->lock);
+	return (void *)client;
+}
+
+/**
+ * Close a session with the router, this is the mechanism
+ * by which a router may cleanup data structure etc.
+ *
+ * @param instance		The router instance data
+ * @param router_session	The session being closed
+ */
+static	void 	
+closeSession(ROUTER *instance, void *router_session)
+{
+CLI_INSTANCE	*inst = (CLI_INSTANCE *)instance;
+CLI_SESSION	*session = (CLI_SESSION *)router_session;
+
+	/*
+	 * Close the connection to the backend
+	 */
+	session->session->client->func.close(session->session->client, 0);
+
+	spinlock_acquire(&inst->lock);
+	if (inst->sessions == session)
+		inst->sessions = session->next;
+	else
+	{
+		CLI_SESSION *ptr = inst->sessions;
+		while (ptr && ptr->next != session)
+			ptr = ptr->next;
+		if (ptr)
+			ptr->next = session->next;
+	}
+	spinlock_release(&inst->lock);
+
+	/*
+	 * We are no longer in the linked list, free
+	 * all the memory and other resources associated
+	 * to the client session.
+	 */
+	free(session);
+}
+
+/**
+ * We have data from the client, we must route it to the backend.
+ * This is simply a case of sending it to the connection that was
+ * chosen when we started the client session.
+ *
+ * @param instance		The router instance
+ * @param router_session	The router session returned from the newSession call
+ * @param queue			The queue of data buffers to route
+ * @return The number of bytes sent
+ */
+static	int	
+execute(ROUTER *instance, void *router_session, GWBUF *queue)
+{
+CLI_SESSION	*session = (CLI_SESSION *)router_session;
+
+	/* Extract the characters */
+	strncat(session->cmdbuf, GWBUF_DATA(queue), GWBUF_LENGTH(queue));
+	/* Echo back to the user */
+	dcb_write(session->session->client, queue);
+
+	if (strrchr(session->cmdbuf, '\n'))
+	{
+		execute_cmd(session);
+		dcb_printf(session->session->client, "Gateway> ");
+	}
+	return 1;
+}
+
+static struct {
+	char	*cmd;
+	void	(*fn)(DCB *);
+} cmds[] = {
+	{ "show sessions",	dprintAllSessions },
+	{ "show services",	dprintAllServices },
+	{ "show servers",	dprintAllServers },
+	{ "show modules",	dprintAllModules },
+	{ "show dcbs",		dprintAllDCBs },
+	{ NULL,			NULL }
+};
+
+/**
+ * We have a complete line from the user, lookup the commands and execute them
+ *
+ * @param cli		The CLI_SESSION
+ */
+static void
+execute_cmd(CLI_SESSION *cli)
+{
+int	i, found = 0;
+
+	if (!strncmp(cli->cmdbuf, "help", 4))
+	{
+		dcb_printf(cli->session->client, "Available commands:\n");
+		for (i = 0; cmds[i].cmd; i++)
+		{
+			dcb_printf(cli->session->client, "    %s\n", cmds[i].cmd);
+		}
+		found = 1;
+	}
+	else
+	{
+		for (i = 0; cmds[i].cmd; i++)
+		{
+			if (strncmp(cli->cmdbuf, cmds[i].cmd, strlen(cmds[i].cmd)) == 0)
+			{
+				cmds[i].fn(cli->session->client);
+				found = 1;
+			}
+		}
+	}
+	if (!found)
+		dcb_printf(cli->session->client,
+			"Command not known, type help for a list of available commands\n");
+	memset(cli->cmdbuf, 80, 0);
+}

modules/routing/readconnroute.c

@@ -130,7 +130,7 @@ int		i, n;
 	for (server = service->databases, n = 0; server; server = server->nextdb)
 		n++;
 
-	inst->servers = (BACKEND **)calloc(n, sizeof(BACKEND *));
+	inst->servers = (BACKEND **)calloc(n + 1, sizeof(BACKEND *));
 	if (!inst->servers)
 	{
 		free(inst);
@@ -153,6 +153,7 @@ int		i, n;
 		inst->servers[n]->count = 0;
 		n++;
 	}
+	inst->servers[n] = NULL;
 
 	/*
 	 * We have completed the creation of the instance data, so now
@@ -194,7 +195,7 @@ int		i;
 	candidate = inst->servers[0];
 	for (i = 1; inst->servers[i]; i++);
 	{
-		if (inst->servers[i]->count < candidate->count)
+		if (inst->servers[i] && inst->servers[i]->count < candidate->count)
 			candidate = inst->servers[i];
 	}