gdbserver: don't pick a random thread if the current thread dies

[deliverable/binutils-gdb.git] / gdb / gdbserver / server.c

diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c
index 7e388ddcc9be5643d78a9f16ac982c3bda7aa7cb..58907ec4a9ffa3bfbf6845b4c95e5081d2e81fa2 100644 (file)
--- a/gdb/gdbserver/server.c
+++ b/gdb/gdbserver/server.c
@@ -49,7 +49,7 @@ ptid_t general_thread;
 
 int server_waiting;
 
-static int extended_protocol;
+int extended_protocol;
 static int response_needed;
 static int exit_requested;
 
@@ -257,22 +257,22 @@ start_inferior (char **argv)
 
       last_ptid = mywait (pid_to_ptid (signal_pid), &last_status, 0, 0);
 
-      if (last_status.kind != TARGET_WAITKIND_STOPPED)
-       return signal_pid;
-
-      do
+      if (last_status.kind == TARGET_WAITKIND_STOPPED)
        {
-         (*the_target->resume) (&resume_info, 1);
+         do
+           {
+             (*the_target->resume) (&resume_info, 1);
 
-         last_ptid = mywait (pid_to_ptid (signal_pid), &last_status, 0, 0);
-         if (last_status.kind != TARGET_WAITKIND_STOPPED)
-           return signal_pid;
+             last_ptid = mywait (pid_to_ptid (signal_pid), &last_status, 0, 0);
+             if (last_status.kind != TARGET_WAITKIND_STOPPED)
+               break;
 
-         current_thread->last_resume_kind = resume_stop;
-         current_thread->last_status = last_status;
+             current_thread->last_resume_kind = resume_stop;
+             current_thread->last_status = last_status;
+           }
+         while (last_status.value.sig != GDB_SIGNAL_TRAP);
        }
-      while (last_status.value.sig != GDB_SIGNAL_TRAP);
-
+      target_arch_setup ();
       return signal_pid;
     }
 
@@ -280,6 +280,8 @@ start_inferior (char **argv)
      (assuming success).  */
   last_ptid = mywait (pid_to_ptid (signal_pid), &last_status, 0, 0);
 
+  target_arch_setup ();
+
   if (last_status.kind != TARGET_WAITKIND_EXITED
       && last_status.kind != TARGET_WAITKIND_SIGNALLED)
     {
@@ -814,7 +816,10 @@ gdb_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
   res = prepare_to_access_memory ();
   if (res == 0)
     {
-      res = read_inferior_memory (memaddr, myaddr, len);
+      if (set_desired_thread (1))
+       res = read_inferior_memory (memaddr, myaddr, len);
+      else
+       res = 1;
       done_accessing_memory ();
 
       return res == 0 ? len : -1;
@@ -838,7 +843,10 @@ gdb_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
       ret = prepare_to_access_memory ();
       if (ret == 0)
        {
-         ret = write_inferior_memory (memaddr, myaddr, len);
+         if (set_desired_thread (1))
+           ret = write_inferior_memory (memaddr, myaddr, len);
+         else
+           ret = EIO;
          done_accessing_memory ();
        }
       return ret;
@@ -1169,7 +1177,7 @@ handle_qxfer_auxv (const char *annex,
   if (the_target->read_auxv == NULL || writebuf != NULL)
     return -2;
 
-  if (annex[0] != '\0' || !target_running ())
+  if (annex[0] != '\0' || current_thread == NULL)
     return -1;
 
   return (*the_target->read_auxv) (offset, readbuf, len);
@@ -1314,7 +1322,7 @@ handle_qxfer_libraries (const char *annex,
   if (writebuf != NULL)
     return -2;
 
-  if (annex[0] != '\0' || !target_running ())
+  if (annex[0] != '\0' || current_thread == NULL)
     return -1;
 
   total_len = 64;
@@ -1358,7 +1366,7 @@ handle_qxfer_libraries_svr4 (const char *annex,
   if (writebuf != NULL)
     return -2;
 
-  if (!target_running () || the_target->qxfer_libraries_svr4 == NULL)
+  if (current_thread == NULL || the_target->qxfer_libraries_svr4 == NULL)
     return -1;
 
   return the_target->qxfer_libraries_svr4 (annex, readbuf, writebuf, offset, len);
@@ -1387,7 +1395,7 @@ handle_qxfer_siginfo (const char *annex,
   if (the_target->qxfer_siginfo == NULL)
     return -2;
 
-  if (annex[0] != '\0' || !target_running ())
+  if (annex[0] != '\0' || current_thread == NULL)
     return -1;
 
   return (*the_target->qxfer_siginfo) (annex, readbuf, writebuf, offset, len);
@@ -1403,7 +1411,7 @@ handle_qxfer_spu (const char *annex,
   if (the_target->qxfer_spu == NULL)
     return -2;
 
-  if (!target_running ())
+  if (current_thread == NULL)
     return -1;
 
   return (*the_target->qxfer_spu) (annex, readbuf, writebuf, offset, len);
@@ -1421,7 +1429,7 @@ handle_qxfer_statictrace (const char *annex,
   if (writebuf != NULL)
     return -2;
 
-  if (annex[0] != '\0' || !target_running () || current_traceframe == -1)
+  if (annex[0] != '\0' || current_thread == NULL || current_traceframe == -1)
     return -1;
 
   if (traceframe_read_sdata (current_traceframe, offset,
@@ -1484,7 +1492,7 @@ handle_qxfer_threads (const char *annex,
   if (writebuf != NULL)
     return -2;
 
-  if (!target_running () || annex[0] != '\0')
+  if (annex[0] != '\0')
     return -1;
 
   if (offset == 0)
@@ -1580,7 +1588,7 @@ handle_qxfer_fdpic (const char *annex, gdb_byte *readbuf,
   if (the_target->read_loadmap == NULL)
     return -2;
 
-  if (!target_running ())
+  if (current_thread == NULL)
     return -1;
 
   return (*the_target->read_loadmap) (annex, offset, readbuf, len);
@@ -1600,9 +1608,6 @@ handle_qxfer_btrace (const char *annex,
   if (the_target->read_btrace == NULL || writebuf != NULL)
     return -2;
 
-  if (!target_running ())
-    return -1;
-
   if (ptid_equal (general_thread, null_ptid)
       || ptid_equal (general_thread, minus_one_ptid))
     {
@@ -1674,7 +1679,7 @@ handle_qxfer_btrace_conf (const char *annex,
   if (the_target->read_btrace_conf == NULL || writebuf != NULL)
     return -2;
 
-  if (annex[0] != '\0' || !target_running ())
+  if (annex[0] != '\0')
     return -1;
 
   if (ptid_equal (general_thread, null_ptid)
@@ -1976,7 +1981,7 @@ handle_query (char *own_buf, int packet_len, int *new_packet_len_p)
       if (target_supports_tracepoints ())
        tracepoint_look_up_symbols ();
 
-      if (target_running () && the_target->look_up_symbols != NULL)
+      if (current_thread != NULL && the_target->look_up_symbols != NULL)
        (*the_target->look_up_symbols) ();
 
       strcpy (own_buf, "OK");
@@ -2573,8 +2578,6 @@ handle_v_cont (char *own_buf)
   if (i < n)
     resume_info[i] = default_action;
 
-  set_desired_thread (0);
-
   resume (resume_info, n);
   free (resume_info);
   return;
@@ -2876,8 +2879,6 @@ myresume (char *own_buf, int step, int sig)
   int n = 0;
   int valid_cont_thread;
 
-  set_desired_thread (0);
-
   valid_cont_thread = (!ptid_equal (cont_thread, null_ptid)
                         && !ptid_equal (cont_thread, minus_one_ptid));
 
@@ -3608,11 +3609,17 @@ captured_main (int argc, char *argv[])
        }
       CATCH (exception, RETURN_MASK_ERROR)
        {
+         fflush (stdout);
+         fprintf (stderr, "gdbserver: %s\n", exception.message);
+
          if (response_needed)
            {
              write_enn (own_buf);
              putpkt (own_buf);
            }
+
+         if (run_once)
+           throw_quit ("Quit");
        }
       END_CATCH
     }
@@ -3900,14 +3907,13 @@ process_serial_event (void)
                    (struct thread_info *) find_inferior_id (&all_threads,
                                                             general_thread);
                  if (thread == NULL)
-                   {
-                     thread = get_first_thread ();
-                     thread_id = thread->entry.id;
-                   }
+                   thread = get_first_thread ();
+                 thread_id = thread->entry.id;
                }
 
              general_thread = thread_id;
              set_desired_thread (1);
+             gdb_assert (current_thread != NULL);
            }
          else if (own_buf[1] == 'c')
            cont_thread = thread_id;
@@ -3939,9 +3945,13 @@ process_serial_event (void)
        {
          struct regcache *regcache;
 
-         set_desired_thread (1);
-         regcache = get_thread_regcache (current_thread, 1);
-         registers_to_string (regcache, own_buf);
+         if (!set_desired_thread (1))
+           write_enn (own_buf);
+         else
+           {
+             regcache = get_thread_regcache (current_thread, 1);
+             registers_to_string (regcache, own_buf);
+           }
        }
       break;
     case 'G':
@@ -3952,10 +3962,14 @@ process_serial_event (void)
        {
          struct regcache *regcache;
 
-         set_desired_thread (1);
-         regcache = get_thread_regcache (current_thread, 1);
-         registers_from_string (regcache, &own_buf[1]);
-         write_ok (own_buf);
+         if (!set_desired_thread (1))
+           write_enn (own_buf);
+         else
+           {
+             regcache = get_thread_regcache (current_thread, 1);
+             registers_from_string (regcache, &own_buf[1]);
+             write_ok (own_buf);
+           }
        }
       break;
     case 'm':
@@ -4112,7 +4126,20 @@ process_serial_event (void)
 
          /* Wait till we are at 1st instruction in prog.  */
          if (program_argv != NULL)
-           start_inferior (program_argv);
+           {
+             start_inferior (program_argv);
+             if (last_status.kind == TARGET_WAITKIND_STOPPED)
+               {
+                 /* Stopped at the first instruction of the target
+                    process.  */
+                 general_thread = last_ptid;
+               }
+             else
+               {
+                 /* Something went wrong.  */
+                 general_thread = null_ptid;
+               }
+           }
          else
            {
              last_status.kind = TARGET_WAITKIND_EXITED;