Clean up handling of lost targets using new exceptions mechanism.

src/cortexm.c

@@ -37,6 +37,7 @@
 #include "command.h"
 #include "gdb_packet.h"
 #include "cortexm.h"
+#include "morse.h"
 
 #include <unistd.h>
 
@@ -57,6 +58,7 @@ const struct command_s cortexm_cmd_list[] = {
 #define SIGINT 2
 #define SIGTRAP 5
 #define SIGSEGV 11
+#define SIGLOST 29
 
 static int cortexm_regs_read(struct target_s *target, void *data);
 static int cortexm_regs_write(struct target_s *target, const void *data);
@@ -487,12 +489,23 @@ cortexm_halt_wait(struct target_s *target)
 
 	uint32_t dhcsr = 0;
 	volatile struct exception e;
-	TRY_CATCH (e, EXCEPTION_TIMEOUT) {
+	TRY_CATCH (e, EXCEPTION_ALL) {
 		/* If this times out because the target is in WFI then
 		 * the target is still running. */
 		dhcsr = target_mem_read32(target, CORTEXM_DHCSR);
 	}
-	if (e.type || !(dhcsr & CORTEXM_DHCSR_S_HALT))
+	switch (e.type) {
+	case EXCEPTION_ERROR:
+		/* Oh crap, there's no recovery from this... */
+		target_list_free();
+		morse("TARGET LOST.", 1);
+		return SIGLOST;
+	case EXCEPTION_TIMEOUT:
+		/* Timeout isn't a problem, target could be in WFI */
+		return 0;
+	}
+
+	if (!(dhcsr & CORTEXM_DHCSR_S_HALT))
 		return 0;
 
 	/* We've halted.  Let's find out why. */

src/exception.c

@@ -34,6 +34,6 @@ void raise_exception(uint32_t type, const char *msg)
 			longjmp(e->jmpbuf, type);
 		}
 	}
-	PLATFORM_FATAL_ERROR(type);
+	abort();
 }
 

src/gdb_main.c

@@ -158,6 +158,12 @@ gdb_main(void)
 			if (sig < 0)
 				break;
 
+			/* Target disappeared */
+			if (cur_target == NULL) {
+				gdb_putpacket_f("X%02X", sig);
+				break;
+			}
+
 			/* Report reason for halt */
 			if(target_check_hw_wp(cur_target, &watch_addr)) {
 				/* Watchpoint hit */

src/main.c

@@ -28,6 +28,9 @@
 #include "jtagtap.h"
 #include "jtag_scan.h"
 #include "target.h"
+#include "exception.h"
+#include "gdb_packet.h"
+#include "morse.h"
 
 int
 main(int argc, char **argv)
@@ -39,9 +42,18 @@ main(int argc, char **argv)
 	(void) argv;
 	platform_init();
 #endif
-	PLATFORM_SET_FATAL_ERROR_RECOVERY();
 
-	gdb_main();
+	while (true) {
+		volatile struct exception e;
+		TRY_CATCH(e, EXCEPTION_ALL) {
+			gdb_main();
+		}
+		if (e.type == EXCEPTION_ERROR) {
+			gdb_putpacketz("EFF");
+			target_list_free();
+			morse("TARGET LOST.", 1);
+		}
+	}
 
 	/* Should never get here */
 	return 0;

src/platforms/stm32/timing.c

@@ -17,6 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include "general.h"
+#include "morse.h"
 
 #include <libopencm3/cm3/systick.h>
 #include <libopencm3/cm3/scb.h>