Add an "events" system to libpq, whereby applications can get callbacks that

enable them to manage private data associated with PGconns and PGresults.

Andrew Chernow and Merlin Moncure

1 files changed, 70 insertions, 4 deletions

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 5e687c15585..7e77c9a5c7a 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/interfaces/libpq/fe-connect.c,v 1.359 2008/05/29 22:02:44 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/interfaces/libpq/fe-connect.c,v 1.360 2008/09/17 04:31:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1974,6 +1974,21 @@ makeEmptyPGconn(void)
 static void
 freePGconn(PGconn *conn)
 {
+	int			i;
+
+	/* let any event procs clean up their state data */
+	for (i = 0; i < conn->nEvents; i++)
+	{
+		PGEventConnDestroy evt;
+
+		evt.conn = conn;
+		(void) conn->events[i].proc(PGEVT_CONNDESTROY, &evt,
+									conn->events[i].passThrough);
+		free(conn->events[i].name);
+	}
+
+	if (conn->events)
+		free(conn->events);
 	if (conn->pghost)
 		free(conn->pghost);
 	if (conn->pghostaddr)
@@ -2155,8 +2170,30 @@ PQreset(PGconn *conn)
 	{
 		closePGconn(conn);
 
-		if (connectDBStart(conn))
-			(void) connectDBComplete(conn);
+		if (connectDBStart(conn) && connectDBComplete(conn))
+		{
+			/*
+			 * Notify event procs of successful reset.  We treat an event
+			 * proc failure as disabling the connection ... good idea?
+			 */
+			int i;
+
+			for (i = 0; i < conn->nEvents; i++)
+			{
+				PGEventConnReset evt;
+
+				evt.conn = conn;
+				if (!conn->events[i].proc(PGEVT_CONNRESET, &evt,
+										  conn->events[i].passThrough))
+				{
+					conn->status = CONNECTION_BAD;
+					printfPQExpBuffer(&conn->errorMessage,
+									  libpq_gettext("PGEventProc \"%s\" failed during PGEVT_CONNRESET event\n"),
+									  conn->events[i].name);
+					break;
+				}
+			}
+		}
 	}
 }
 
@@ -2190,7 +2227,36 @@ PostgresPollingStatusType
 PQresetPoll(PGconn *conn)
 {
 	if (conn)
-		return PQconnectPoll(conn);
+	{
+		PostgresPollingStatusType status = PQconnectPoll(conn);
+
+		if (status == PGRES_POLLING_OK)
+		{
+			/*
+			 * Notify event procs of successful reset.  We treat an event
+			 * proc failure as disabling the connection ... good idea?
+			 */
+			int i;
+
+			for (i = 0; i < conn->nEvents; i++)
+			{
+				PGEventConnReset evt;
+
+				evt.conn = conn;
+				if (!conn->events[i].proc(PGEVT_CONNRESET, &evt,
+										  conn->events[i].passThrough))
+				{
+					conn->status = CONNECTION_BAD;
+					printfPQExpBuffer(&conn->errorMessage,
+									  libpq_gettext("PGEventProc \"%s\" failed during PGEVT_CONNRESET event\n"),
+									  conn->events[i].name);
+					return PGRES_POLLING_FAILED;
+				}
+			}
+		}
+
+		return status;
+	}
 
 	return PGRES_POLLING_FAILED;
 }