This is the mail archive of the
gdb-prs@sourceware.org
mailing list for the GDB project.
[Bug gdb/20487] Thread sync broken between mi and cli with new-ui command
- From: "cvs-commit at gcc dot gnu.org" <sourceware-bugzilla at sourceware dot org>
- To: gdb-prs at sourceware dot org
- Date: Mon, 03 Oct 2016 21:00:28 +0000
- Subject: [Bug gdb/20487] Thread sync broken between mi and cli with new-ui command
- Auto-submitted: auto-generated
- References: <bug-20487-4717@http.sourceware.org/bugzilla/>
https://sourceware.org/bugzilla/show_bug.cgi?id=20487
--- Comment #12 from cvs-commit at gcc dot gnu.org <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Simon Marchi <simark@sourceware.org>:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=4034d0ff52b0f346efedd2d335ccbc672466da45
commit 4034d0ff52b0f346efedd2d335ccbc672466da45
Author: Antoine Tremblay <antoine.tremblay@ericsson.com>
Date: Mon Oct 3 16:52:44 2016 -0400
Emit inferior, thread and frame selection events to all UIs
With this patch, when an inferior, thread or frame is explicitly
selected by the user, notifications will appear on all CLI and MI UIs.
When a GDB console is integrated in a front-end, this allows the
front-end to follow a selection made by the user ont he CLI, and it
informs the user about selection changes made behind the scenes by the
front-end.
This patch addresses PR gdb/20487.
In order to communicate frame changes to the front-end, this patch adds
a new field to the =thread-selected event for the selected frame. The
idea is that since inferior/thread/frame can be seen as a composition,
it makes sense to send them together in the same event. The vision
would be to eventually send the inferior information as well, if we find
that it's needed, although the "=thread-selected" event would be
ill-named for that job.
Front-ends need to handle this new field if they want to follow the
frame selection changes that originate from the console. The format of
the frame attribute is the same as what is found in the *stopped events.
Here's a detailed example for each command and the events they generate:
thread
------
1. CLI command:
thread 1.3
MI event:
=thread-selected,id="3",frame={...}
2. MI command:
-thread-select 3
CLI event:
[Switching to thread 1.3 ...]
3. MI command (CLI-in-MI):
thread 1.3
MI event/reply:
&"thread 1.3\n"
~"#0 child_sub_function () ...
=thread-selected,id="3",frame={level="0",...}
^done
frame
-----
1. CLI command:
frame 1
MI event:
=thread-selected,id="3",frame={level="1",...}
2. MI command:
-stack-select-frame 1
CLI event:
#1 0x00000000004007f0 in child_function...
3. MI command (CLI-in-MI):
frame 1
MI event/reply:
&"frame 1\n"
~"#1 0x00000000004007f9 in ..."
=thread-selected,id="3",frame={level="1"...}
^done
inferior
--------
Inferior selection events only go from the console to MI, since there's
no way to select the inferior in pure MI.
1. CLI command:
inferior 2
MI event:
=thread-selected,id="3"
Note that if the user selects an inferior that is not started or exited,
the MI doesn't receive a notification. Since there is no threads to
select, the =thread-selected event does not apply...
2. MI command (CLI-in-MI):
inferior 2
MI event/reply:
&"inferior 2\n"
~"[Switching to inferior 2 ...]"
=thread-selected,id="4",frame={level="0"...}
^done
Internal implementation detail: this patch makes it possible to suppress
notifications caused by a CLI command, like what is done in mi-interp.c.
This means that it's now possible to use the
add_com_suppress_notification function to register a command with some
event suppressed. It is used to implement the select-frame command in
this patch.
The function command_notifies_uscc_observer was added to extract
the rather complicated logical expression from the if statement. It is
also now clearer what that logic does: if the command used by the user
already notifies the user_selected_context_changed observer, there is
not need to notify it again. It therefore protects again emitting the
event twice.
No regressions, tested on ubuntu 14.04 x86 with target boards unix and
native-extended-gdbserver.
gdb/ChangeLog:
YYYY-MM-DD Antoine Tremblay <antoine.tremblay@ericsson.com>
YYYY-MM-DD Simon Marchi <simon.marchi@ericsson.com>
PR gdb/20487
* NEWS: Mention new frame field of =thread-selected event.
* cli/cli-decode.c (add_cmd): Initialize c->suppress_notification.
(add_com_suppress_notification): New function definition.
(cmd_func): Set and restore the suppress_notification flag.
* cli/cli-deicode.h (struct cmd_list_element)
<suppress_notification>: New field.
* cli/cli-interp.c (cli_suppress_notification): New global variable.
(cli_on_user_selected_context_changed): New function.
(_initialize_cli_interp): Attach to user_selected_context_changed
observer.
* command.h (struct cli_suppress_notification): New structure.
(cli_suppress_notification): New global variable declaration.
(add_com_suppress_notification): New function declaration.
* defs.h (enum user_selected_what_flag): New enum.
(user_selected_what): New enum flag type.
* frame.h (print_stack_frame_to_uiout): New function declaration.
* gdbthread.h (print_selected_thread_frame): New function declaration.
* inferior.c (print_selected_inferior): New function definition.
(inferior_command): Remove printing of inferior/thread/frame switch
notifications, notify user_selected_context_changed observer.
* inferior.h (print_selected_inferior): New function declaration.
* mi/mi-cmds.c (struct mi_cmd): Add user_selected_context
suppression to stack-select-frame and thread-select commands.
* mi/mi-interp.c (struct mi_suppress_notification)
<user_selected_context>: Initialize.
(mi_user_selected_context_changed): New function definition.
(_initialize_mi_interp): Attach to user_selected_context_changed.
* mi/mi-main.c (mi_cmd_thread_select): Print thread selection reply.
(mi_execute_command): Handle notification suppression. Notify
user_selected_context_changed observer on thread change instead of
printing
event directly. Don't send it if command already sends the
notification.
(command_notifies_uscc_observer): New function.
(mi_cmd_execute): Don't handle notification suppression.
* mi/mi-main.h (struct mi_suppress_notification)
<user_selected_context>: New field.
* stack.c (print_stack_frame_to_uiout): New function definition.
(select_frame_command): Notify user_selected_context_changed
observer.
(frame_command): Call print_selected_thread_frame if there's no frame
change or notify user_selected_context_changed observer if there is.
(up_command): Notify user_selected_context_changed observer.
(down_command): Likewise.
(_initialize_stack): Suppress user_selected_context notification for
command select-frame.
* thread.c (thread_command): Notify
user_selected_context_changed if the thread has changed, print
thread info directly if it hasn't.
(do_captured_thread_select): Do not print thread switch event.
(print_selected_thread_frame): New function definition.
* tui/tui-interp.c (tui_on_user_selected_context_changed):
New function definition.
(_initialize_tui_interp): Attach to user_selected_context_changed
observer.
gdb/doc/ChangeLog:
PR gdb/20487
* gdb.texinfo (Context management): Update mention of frame
change notifications.
(gdb/mi Async Records): Document frame field in
=thread-select event.
* observer.texi (GDB Observers): New user_selected_context_changed
observer.
gdb/testsuite/ChangeLog:
PR gdb/20487
* gdb.mi/mi-pthreads.exp (check_mi_thread_command_set): Adapt
=thread-select-event check.
--- Comment #13 from cvs-commit at gcc dot gnu.org <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Simon Marchi <simark@sourceware.org>:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=9c36d9544f0987cbd840a19552af3343252d28a0
commit 9c36d9544f0987cbd840a19552af3343252d28a0
Author: Antoine Tremblay <antoine.tremblay@ericsson.com>
Date: Mon Oct 3 16:55:35 2016 -0400
Add test for user context selection sync
This patch adds a test to verify that events are sent properly to all
UIs when the user selection context (inferior, thread, frame) changes.
The goal of the C test file is to provide two threads that are stopped with
the
same predictable backtrace (so that we can test frame switching). The
barrier
helps us know when the child threads are started. Then, scheduler-locking
is
used to bring each thread one by one to the position we expect them to be
during the test.
gdb/testsuite/ChangeLog:
YYYY-MM-DD Antoine Tremblay <antoine.tremblay@ericsson.com>
YYYY-MM-DD Simon Marchi <simon.marchi@ericsson.com>
PR gdb/20487
* gdb.mi/user-selected-context-sync.exp: New file.
* gdb.mi/user-selected-context-sync.c: New file.
--
You are receiving this mail because:
You are on the CC list for the bug.