Fix PR gdb/20418 - Problems with synchronous commands and new-ui
authorPedro Alves <palves@redhat.com>
Tue, 9 Aug 2016 21:45:40 +0000 (22:45 +0100)
committerPedro Alves <palves@redhat.com>
Tue, 9 Aug 2016 21:50:45 +0000 (22:50 +0100)
commit3eb7562a983bab4c768983bcd85708852d171121
tree9ceb489cbd1f48967e11a4a60d1f34d9b57ec007
parent80614914274f7166baea2ec656aec6a949869324
Fix PR gdb/20418 - Problems with synchronous commands and new-ui

When executing commands on a secondary UI running the MI interpreter,
some commands that should be synchronous are not.  MI incorrectly
continues processing input right after the synchronous command is
sent, before the target stops.

The problem happens when we emit MI async events (=library-loaded,
etc.), and we go about restoring the previous terminal state, we end
up calling target_terminal_ours, which incorrectly always installs the
current UI's input_fd in the event loop...  That is, code like this:

   old_chain = make_cleanup_restore_target_terminal ();
   target_terminal_ours_for_output ();

   fprintf_unfiltered (mi->event_channel, "library-loaded");

...

   do_cleanups (old_chain);

The fix is to move the add_file_handler/delete_file_handler calls out
of target_terminal_$foo, making these completely no-ops unless called
with the main UI as current UI.

gdb/ChangeLog:
2016-08-09  Pedro Alves  <palves@redhat.com>

PR gdb/20418
* event-top.c (ui_register_input_event_handler)
(ui_unregister_input_event_handler): New functions.
(async_enable_stdin): Register input in the event loop.
(async_disable_stdin): Unregister input from the event loop.
(gdb_setup_readline): Register input in the event loop.
* infrun.c (check_curr_ui_sync_execution_done): Register input in
the event loop.
* target.c (target_terminal_inferior): Don't unregister input from
the event loop.
(target_terminal_ours): Don't register input in the event loop.
* target.h (target_terminal_inferior)
(target_terminal_ours_for_output, target_terminal_ours): Update
comments.
* top.h (ui_register_input_event_handler)
(ui_unregister_input_event_handler): New declarations.
* utils.c (ui_unregister_input_event_handler_cleanup)
(prepare_to_handle_input): New functions.
(defaulted_query, prompt_for_continue): Use
prepare_to_handle_input.

gdb/testsuite/ChangeLog:
2016-08-09  Pedro Alves  <palves@redhat.com>
    Simon Marchi  <simon.marchi@ericsson.com>

PR gdb/20418
* gdb.mi/new-ui-mi-sync.c, gdb.mi/new-ui-mi-sync.exp: New files.
* lib/mi-support.exp (mi_expect_interrupt): Remove anchors.
gdb/ChangeLog
gdb/event-top.c
gdb/infrun.c
gdb/target.c
gdb/target.h
gdb/testsuite/ChangeLog
gdb/testsuite/gdb.mi/new-ui-mi-sync.c [new file with mode: 0644]
gdb/testsuite/gdb.mi/new-ui-mi-sync.exp [new file with mode: 0644]
gdb/testsuite/lib/mi-support.exp
gdb/top.h
gdb/utils.c