Support signal reception in user-mode. Handle when the peer terminates or aborts the connection.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4483 c046a42c-6fe2-441c-8c8c-71466251a162

gdbstub.c

@@ -65,6 +65,7 @@ typedef struct GDBState {
     int line_csum;
     uint8_t last_packet[4100];
     int last_packet_len;
+    int signal;
 #ifdef CONFIG_USER_ONLY
     int fd;
     int running_state;
@@ -93,9 +94,13 @@ static int get_char(GDBState *s)
     for(;;) {
         ret = recv(s->fd, &ch, 1, 0);
         if (ret < 0) {
+            if (errno == ECONNRESET)
+                s->fd = -1;
             if (errno != EINTR && errno != EAGAIN)
                 return -1;
         } else if (ret == 0) {
+            close(s->fd);
+            s->fd = -1;
             return -1;
         } else {
             break;
@@ -991,6 +996,10 @@ static int gdb_handle_packet(GDBState *s, CPUState *env, const char *line_buf)
         }
         gdb_continue(s);
 	return RS_IDLE;
+    case 'C':
+        s->signal = strtoul(p, (char **)&p, 16);
+        gdb_continue(s);
+        return RS_IDLE;
     case 'k':
         /* Kill the target */
         fprintf(stderr, "\nQEMU: Terminated via GDBstub\n");
@@ -1364,10 +1373,9 @@ gdb_handlesig (CPUState *env, int sig)
   char buf[256];
   int n;
 
-  if (gdbserver_fd < 0)
-    return sig;
-
   s = &gdbserver_state;
+  if (gdbserver_fd < 0 || s->fd < 0)
+    return sig;
 
   /* disable single step if it was enabled */
   cpu_single_step(env, 0);
@@ -1378,6 +1386,10 @@ gdb_handlesig (CPUState *env, int sig)
       snprintf(buf, sizeof(buf), "S%02x", sig);
       put_packet(s, buf);
     }
+  /* put_packet() might have detected that the peer terminated the 
+     connection.  */
+  if (s->fd < 0)
+      return sig;
 
   sig = 0;
   s->state = RS_IDLE;
@@ -1398,6 +1410,8 @@ gdb_handlesig (CPUState *env, int sig)
           return sig;
         }
   }
+  sig = s->signal;
+  s->signal = 0;
   return sig;
 }
 
@@ -1407,10 +1421,9 @@ void gdb_exit(CPUState *env, int code)
   GDBState *s;
   char buf[4];
 
-  if (gdbserver_fd < 0)
-    return;
-
   s = &gdbserver_state;
+  if (gdbserver_fd < 0 || s->fd < 0)
+    return;
 
   snprintf(buf, sizeof(buf), "W%02x", code);
   put_packet(s, buf);