gdb_server: add target_debug_reason for program exit detection

Currently, there is no way to notify gdb that program has exited.
Add new target_debug_reason called DBG_REASON_EXIT to notify gdb
the condition has occured. If the debug reason is DBG_REASON_EXIT,
gdb_server will send 'W' packet to tell gdb the process has exited.

Change-Id: I7a371da292716a3e6ac4cc2c31b009a651fe047a
Signed-off-by: Hsiangkai Wang <hsiangkai@gmail.com>
Reviewed-on: http://openocd.zylin.com/1242
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

4 files changed, 42 insertions, 30 deletions

diff --git a/src/server/gdb_server.c b/src/server/gdb_server.c
index 14925a2..c4ad91c 100644
--- a/src/server/gdb_server.c
+++ b/src/server/gdb_server.c
@@ -702,40 +702,44 @@ static void gdb_signal_reply(struct target *target, struct connection *connectio
 	int sig_reply_len;
 	int signal_var;
 
-	if (gdb_connection->ctrl_c) {
-		signal_var = 0x2;
-		gdb_connection->ctrl_c = 0;
-	} else
-		signal_var = gdb_last_signal(target);
+	if (target->debug_reason == DBG_REASON_EXIT) {
+		sig_reply_len = snprintf(sig_reply, sizeof(sig_reply), "W00");
+	} else {
+		if (gdb_connection->ctrl_c) {
+			signal_var = 0x2;
+			gdb_connection->ctrl_c = 0;
+		} else
+			signal_var = gdb_last_signal(target);
 
-	stop_reason[0] = '\0';
-	if (target->debug_reason == DBG_REASON_WATCHPOINT) {
-		enum watchpoint_rw hit_wp_type;
-		uint32_t hit_wp_address;
+		stop_reason[0] = '\0';
+		if (target->debug_reason == DBG_REASON_WATCHPOINT) {
+			enum watchpoint_rw hit_wp_type;
+			uint32_t hit_wp_address;
 
-		if (watchpoint_hit(target, &hit_wp_type, &hit_wp_address) == ERROR_OK) {
+			if (watchpoint_hit(target, &hit_wp_type, &hit_wp_address) == ERROR_OK) {
 
-			switch (hit_wp_type) {
-				case WPT_WRITE:
-					snprintf(stop_reason, sizeof(stop_reason),
-							"watch:%08x;", hit_wp_address);
-					break;
-				case WPT_READ:
-					snprintf(stop_reason, sizeof(stop_reason),
-							"rwatch:%08x;", hit_wp_address);
-					break;
-				case WPT_ACCESS:
-					snprintf(stop_reason, sizeof(stop_reason),
-							"awatch:%08x;", hit_wp_address);
-					break;
-				default:
-					break;
+				switch (hit_wp_type) {
+					case WPT_WRITE:
+						snprintf(stop_reason, sizeof(stop_reason),
+								"watch:%08x;", hit_wp_address);
+						break;
+					case WPT_READ:
+						snprintf(stop_reason, sizeof(stop_reason),
+								"rwatch:%08x;", hit_wp_address);
+						break;
+					case WPT_ACCESS:
+						snprintf(stop_reason, sizeof(stop_reason),
+								"awatch:%08x;", hit_wp_address);
+						break;
+					default:
+						break;
+				}
 			}
 		}
-	}
 
-	sig_reply_len = snprintf(sig_reply, sizeof(sig_reply), "T%2.2x%s",
-			signal_var, stop_reason);
+		sig_reply_len = snprintf(sig_reply, sizeof(sig_reply), "T%2.2x%s",
+				signal_var, stop_reason);
+	}
 
 	gdb_put_packet(connection, sig_reply, sig_reply_len);
 	gdb_connection->frontend_state = TARGET_HALTED;
diff --git a/src/target/nds32.c b/src/target/nds32.c
index c4bd63a..50d6e3b 100644
--- a/src/target/nds32.c
+++ b/src/target/nds32.c
@@ -1921,7 +1921,13 @@ int nds32_examine_debug_reason(struct nds32 *nds32)
 							&instruction))
 					return ERROR_FAIL;
 
-				target->debug_reason = DBG_REASON_BREAKPOINT;
+				/* hit 'break 0x7FFF' */
+				if ((instruction.info.opc_6 == 0x32) &&
+					(instruction.info.sub_opc == 0xA) &&
+					(instruction.info.imm == 0x7FFF)) {
+					target->debug_reason = DBG_REASON_EXIT;
+				} else
+					target->debug_reason = DBG_REASON_BREAKPOINT;
 			}
 			break;
 		case NDS32_DEBUG_DATA_ADDR_WATCHPOINT_PRECISE:
diff --git a/src/target/target.c b/src/target/target.c
index 442f0d9..1fe89eb 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -228,6 +228,7 @@ static const Jim_Nvp nvp_target_debug_reason[] = {
 	{ .name = "watchpoint-and-breakpoint", .value = DBG_REASON_WPTANDBKPT },
 	{ .name = "single-step"              , .value = DBG_REASON_SINGLESTEP },
 	{ .name = "target-not-halted"        , .value = DBG_REASON_NOTHALTED  },
+	{ .name = "program-exit"             , .value = DBG_REASON_EXIT },
 	{ .name = "undefined"                , .value = DBG_REASON_UNDEFINED },
 	{ .name = NULL, .value = -1 },
 };
diff --git a/src/target/target.h b/src/target/target.h
index ee282b1..44f382a 100644
--- a/src/target/target.h
+++ b/src/target/target.h
@@ -83,7 +83,8 @@ enum target_debug_reason {
 	DBG_REASON_WPTANDBKPT = 3,
 	DBG_REASON_SINGLESTEP = 4,
 	DBG_REASON_NOTHALTED = 5,
-	DBG_REASON_UNDEFINED = 6
+	DBG_REASON_EXIT = 6,
+	DBG_REASON_UNDEFINED = 7,
 };
 
 enum target_endianness {