Improved to diagnostic routines and documentation for the debug cli interpreter

core/dcb.c

@@ -436,10 +436,10 @@ DCB	*dcb;
 }
 
 /**
- * Diagnostic to print a DCB
+ * Diagnostic to print a DCB to another DCB
  *
+ * @param pdcb	The DCB to which send the output
  * @param dcb	The DCB to print
- *
  */
 void
 dprintDCB(DCB *pdcb, DCB *dcb)
@@ -448,6 +448,7 @@ dprintDCB(DCB *pdcb, DCB *dcb)
 	dcb_printf(pdcb, "\tDCB state: 		%s\n", gw_dcb_state2string(dcb->state));
 	if (dcb->remote)
 		dcb_printf(pdcb, "\tConnected to:		%s\n", dcb->remote);
+	dcb_printf(pdcb, "\tOwning Session:   	%d\n", dcb->session);
 	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);
@@ -471,7 +472,7 @@ gw_dcb_state2string (int state) {
 		case DCB_STATE_IDLE:
 			return "DCB not yet in polling";
 		case DCB_STATE_POLLING:
-			return "DCB in the EPOLL";
+			return "DCB in the polling loop";
 		case DCB_STATE_PROCESSING:
 			return "DCB processing event";
 		case DCB_STATE_LISTENING:

core/server.c

@@ -160,6 +160,7 @@ SERVER	*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);
+		dcb_printf(dcb, "\tNumber of connections:	%d\n", ptr->stats.n_connections);
 		ptr = ptr->next;
 	}
 	spinlock_release(&server_spin);

core/session.c

@@ -152,6 +152,8 @@ SESSION	*ptr;
  *
  * Designed to be called within a debugger session in order
  * to display all active sessions within the gateway
+ *
+ * @param dcb	The DCB to print to
  */
 void
 dprintAllSessions(DCB *dcb)
@@ -172,3 +174,46 @@ SESSION	*ptr;
 	}
 	spinlock_release(&session_spin);
 }
+
+/**
+ * Print a particular session to a DCB
+ *
+ * Designed to be called within a debugger session in order
+ * to display all active sessions within the gateway
+ *
+ * @param dcb	The DCB to print to
+ * @param ptr	The session to print
+ */
+void
+dprintSession(DCB *dcb, SESSION *ptr)
+{
+	dcb_printf(dcb, "Session %p\n", ptr);
+	dcb_printf(dcb, "\tState:    		%s\n", session_state(ptr->state));
+	dcb_printf(dcb, "\tService:		%s (%p)\n", ptr->service->name, ptr->service);
+	dcb_printf(dcb, "\tClient DCB:		%p\n", ptr->client);
+	if (ptr->client && ptr->client->remote)
+		dcb_printf(dcb, "\tClient Address:		%s\n", ptr->client->remote);
+	dcb_printf(dcb, "\tConnected:		%s", asctime(localtime(&ptr->stats.connect)));
+}
+
+/**
+ * Convert a session state to a string representation
+ *
+ * @param state		The session state
+ * @return A string representation of the session state
+ */
+char *
+session_state(int state)
+{
+	switch (state)
+	{
+	case SESSION_STATE_ALLOC:
+		return "Session Allocated";
+	case SESSION_STATE_READY:
+		return "Session Ready";
+	case SESSION_STATE_LISTENER:
+		return "Listener Session";
+	default:
+		return "Invalid State";
+	}
+}

include/server.h

@@ -17,6 +17,7 @@
  *
  * Copyright SkySQL Ab 2013
  */
+#include <dcb.h>
 
 /**
  * @file service.h
@@ -59,5 +60,5 @@ extern SERVER	*server_alloc(char *, char *, unsigned short);
 extern int	server_free(SERVER *);
 extern void	printServer(SERVER *);
 extern void	printAllServers();
-extern void	dprintAllServers();
+extern void	dprintAllServers(DCB *);
 #endif

include/session.h

@@ -54,7 +54,7 @@ typedef struct session {
 	struct dcb	*client;	/**< The client connection */
 	struct dcb	*backends;	/**< The set of backend servers */
 	void 		*data;		/**< The session data */
-	void		*router_session;/**< The router insatnce data */
+	void		*router_session;/**< The router instance data */
 	SESSION_STATS	stats;		/**< Session statistics */
 	struct service	*service;	/**< The service this session is using */
 	struct session	*next;		/**< Linked list of all sessions */
@@ -71,4 +71,6 @@ extern void	session_free(SESSION *);
 extern void	printAllSessions();
 extern void	printSession(SESSION *);
 extern void	dprintAllSessions(struct dcb *);
+extern void	dprintSession(struct dcb *, SESSION *);
+extern char	*session_state(int);
 #endif

modules/routing/debugcmd.c

@@ -19,6 +19,17 @@
 /**
  * @file debugcmd.c  - The debug CLI command line interpreter
  *
+ * The command interpreter for the dbug user interface. The command
+ * structure is such that there are a numerb of commands, notably
+ * show and a set of subcommands, the things to show in this case.
+ *
+ * Each subcommand has a handler function defined for it that is passeed
+ * the DCB to use to print the output of the commands and up to 3 arguments
+ * as numeric values.
+ *
+ * There are two "built in" commands, the help command and the quit
+ * command.
+ *
  * @verbatim
  * Revision History
  *
@@ -54,8 +65,12 @@ struct subcommand {
 	char	*help;
 };
 
+/**
+ * The subcommands of the show command
+ */
 struct subcommand showoptions[] = {
 	{ "sessions",	0, dprintAllSessions, 	"Show all active sessions in the gateway" },
+	{ "session",	1, dprintSession, 	"Show a single session in the gateway, e.g. show session 0x284830" },
 	{ "services",	0, dprintAllServices,	"Show all configured services in the gateway" },
 	{ "servers",	0, dprintAllServers,	"Show all configured servers" },
 	{ "modules",	0, dprintAllModules,	"Show all currently loaded modules" },
@@ -77,6 +92,13 @@ static struct {
 };
 
 
+/**
+ * Convert a string argument to a numeric, observing prefixes
+ * for number bases, e.g. 0x for hex, 0 for octal
+ *
+ * @param arg	The string representation of the argument
+ * @return The argument as a long integer
+ */
 static long
 convert_arg(char *arg)
 {
@@ -86,6 +108,14 @@ convert_arg(char *arg)
 /**
  * We have a complete line from the user, lookup the commands and execute them
  *
+ * Commands are tokenised based on white space and then the firt
+ * word is checked againts the cmds table. If a amtch is found the
+ * second word is compared to the different options for that command.
+ *
+ * Commands may also take up to 3 additional arguments, these are all
+ * assumed to the numeric values and will be converted before being passed
+ * to the handler function for the command.
+ *
  * @param cli		The CLI_SESSION
  * @return	Returns 0 if the interpreter should exit
  */