From: Stefan Hajnoczi <stefanha@gmail.com>
Date: Wed, 15 Apr 2009 16:16:31 +0000 (+0100)
Subject: [gdb] Allow resynchronisation with gdb
X-Git-Tag: v0.9.8~168
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38a1d0fe3f92c74d848a8665d8d43392bc23bbfc;p=thirdparty%2Fipxe.git

[gdb] Allow resynchronisation with gdb

This replaces the gdbstub's polite NAK behavior with retransmission of
the current outstanding reply packet.  It solves situations where gdb
and gPXE's gdbstub get out of sync due to the lack of flow control in
the gdb protocol spec.

Signed-off-by: Michael Brown <mcb30@etherboot.org>
---

diff --git a/src/core/gdbstub.c b/src/core/gdbstub.c
index 45df7f2b2..c80839558 100644
--- a/src/core/gdbstub.c
+++ b/src/core/gdbstub.c
@@ -344,12 +344,10 @@ static void gdbstub_state_cksum2 ( struct gdbstub *stub, char ch ) {
 static void gdbstub_state_wait_ack ( struct gdbstub *stub, char ch ) {
 	if ( ch == '+' ) {
 		stub->parse = gdbstub_state_new;
-	} else if ( ch == '-' ) {
-		gdbstub_tx_packet ( stub ); /* retransmit */
-	} else if ( ch == '$' ) {
-		/* GDB is reconnecting, drop our packet and listen to GDB */
-		stub->trans->send ( "-", 1 );
-		stub->parse = gdbstub_state_new;
+	} else {
+		/* This retransmit is very aggressive but necessary to keep
+		 * in sync with GDB. */
+		gdbstub_tx_packet ( stub );
 	}
 }