Enabling target-async by default will require implementing sync
execution on top of an async target, much like foreground command are
implemented on the CLI in async mode.
In order to do that, we will need better control of when to print the
MI prompt. Currently the interp->display_prompt_p hook is all we
have, and MI just always returns false, meaning, make
display_gdb_prompt a no-op. We'll need to be able to know to print
the MI prompt in some of the conditions that display_gdb_prompt is
called from the core, but not all.
This is all a litte twisted currently. As we can see,
display_gdb_prompt is really CLI specific, so make the console
interpreters (console/tui) themselves call it. To be able to do that,
and add a few different observers that the interpreters can use to
distinguish when or why the the prompt is being printed:
#1 - one called whenever a command is cancelled due to an error.
#2 - another for when a foreground command just finished.
In both cases, CLI wants to print the prompt, while MI doesn't.
MI will want to print the prompt in the second case when in a special
MI mode.
The display_gdb_prompt call in interp_set made me pause. The comment
there reads:
/* Finally, put up the new prompt to show that we are indeed here.
Also, display_gdb_prompt for the console does some readline magic
which is needed for the console interpreter, at least... */
But, that looks very much like a no-op to me currently:
- the MI interpreter always return false in the prompt hook, meaning
actually display no prompt.
- the interpreter used at that point is still quiet. And the
console/tui interpreters return false in the prompt hook if they're
quiet, meaning actually display no prompt.
The only remaining possible use would then be the readline magic. But
whatever that might have been, it's not reacheable today either,
because display_gdb_prompt returns early, before touching readline if
the interpreter returns false in the display_prompt_p hook.
Tested on x86_64 Fedora 20, sync and async modes.
gdb/
2014-05-29 Pedro Alves <palves@redhat.com>
* cli/cli-interp.c (cli_interpreter_display_prompt_p): Delete.
(_initialize_cli_interp): Adjust.
* event-loop.c: Include "observer.h".
(start_event_loop): Notify 'command_error' observers instead of
calling display_gdb_prompt. Remove FIXME comment.
* event-top.c (display_gdb_prompt): Remove call into the
interpreters.
* inf-loop.c: Include "observer.h".
(inferior_event_handler): Notify 'command_error' observers instead
of calling display_gdb_prompt.
* infrun.c (fetch_inferior_event): Notify 'sync_execution_done'
observers instead of calling display_gdb_prompt.
* interps.c (interp_set): Don't call display_gdb_prompt.
(current_interp_display_prompt_p): Delete.
* interps.h (interp_prompt_p): Delete declaration.
(interp_prompt_p_ftype): Delete.
(struct interp_procs) <prompt_proc_p>: Delete field.
(current_interp_display_prompt_p): Delete declaration.
* mi-interp.c (mi_interpreter_prompt_p): Delete.
(_initialize_mi_interp): Adjust.
* tui-interp.c (tui_init): Install 'sync_execution_done' and
'command_error' observers.
(tui_on_sync_execution_done, tui_on_command_error): New
functions.
(tui_display_prompt_p): Delete.
(_initialize_tui_interp): Adjust.
gdb/doc/
2014-05-29 Pedro Alves <palves@redhat.com>
* observer.texi (sync_execution_done, command_error): New
subjects.
The other part of PR gdb/13860 is about console execution commands in
MI getting their output half lost. E.g., take the finish command,
executed on a frontend's GDB console:
sync:
finish
&"finish\n"
~"Run till exit from #0 usleep (useconds=10) at ../sysdeps/unix/sysv/linux/usleep.c:27\n"
^running
*running,thread-id="1"
(gdb)
~"0x00000000004004d7 in foo () at stepinf.c:6\n"
~"6\t usleep (10);\n"
~"Value returned is $1 = 0\n"
*stopped,reason="function-finished",frame={addr="0x00000000004004d7",func="foo",args=[],file="stepinf.c",fullname="/home/pedro/gdb/tests/stepinf.c",line="6"},thread-id="1",stopped-threads="all",core="1"
async:
finish
&"finish\n"
~"Run till exit from #0 usleep (useconds=10) at ../sysdeps/unix/sysv/linux/usleep.c:27\n"
^running
*running,thread-id="1"
(gdb)
*stopped,reason="function-finished",frame={addr="0x00000000004004d7",func="foo",args=[],file="stepinf.c",fullname="/home/pedro/gdb/tests/stepinf.c",line="6"},gdb-result-var="$1",return-value="0",thread-id="1",stopped-threads="all",core="0"
Note how all the "Value returned" etc. output is missing in async mode.
The same happens with e.g., catchpoints:
=breakpoint-modified,bkpt={number="1",type="catchpoint",disp="keep",enabled="y",what="22016",times="1"}
~"\nCatchpoint "
~"1 (forked process 22016), 0x0000003791cbd8a6 in __libc_fork () at ../nptl/sysdeps/unix/sysv/linux/fork.c:131\n"
~"131\t pid = ARCH_FORK ();\n"
*stopped,reason="fork",disp="keep",bkptno="1",newpid="22016",frame={addr="0x0000003791cbd8a6",func="__libc_fork",args=[],file="../nptl/sysdeps/unix/sysv/linux/fork.c",fullname="/usr/src/debug/glibc-2.14-394-g8f3b1ff/nptl/sysdeps/unix/sysv/linux/fork.c",line="131"},thread-id="1",stopped-threads="all",core="0"
where all those ~ lines are missing in async mode, or just the "step"
current line indication:
s
&"s\n"
^running
*running,thread-id="all"
(gdb)
~"13\t foo ();\n"
*stopped,frame={addr="0x00000000004004ef",func="main",args=[{name="argc",value="1"},{name="argv",value="0x7fffffffdd78"}],file="stepinf.c",fullname="/home/pedro/gdb/tests/stepinf.c",line="13"},thread-id="1",stopped-threads="all",core="3"
(gdb)
Or in the case of the PRs example, the "Stopped due to shared library
event" note:
start
&"start\n"
~"Temporary breakpoint 1 at 0x400608: file ../../../src/gdb/testsuite/gdb.mi/solib-main.c, line 21.\n"
=breakpoint-created,bkpt={number="1",type="breakpoint",disp="del",enabled="y",addr="0x0000000000400608",func="main",file="../../../src/gdb/testsuite/gdb.mi/solib-main.c",fullname="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.mi/solib-main.c",line="21",times="0",original-location="main"}
~"Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main \n"
=thread-group-started,id="i1",pid="21990"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",symbols-loaded="0",thread-group="i1"
~"Stopped due to shared library event (no libraries added or removed)\n"
*stopped,reason="solib-event",thread-id="1",stopped-threads="all",core="3"
(gdb)
IMO, if you're typing execution commands in a frontend's console, you
expect to see their output. Indeed it's what you get in sync mode. I
think async mode should do the same. Deciding what to mirror to the
console wrt to breakpoints and random stops gets messy real fast.
E.g., say "s" trips on a breakpoint. We'd clearly want to mirror the
event to the console in this case. But what about more complicated
cases like "s&; thread n; s&", and one of those steps spawning a new
thread, and that thread hitting a breakpoint? It's impossible in
general to track whether the thread had any relation to the commands
that had been executed. So I think we should just simplify and always
mirror breakpoints and random events to the console.
Notes:
- mi->out is the same as gdb_stdout when MI is the current
interpreter. I think that referring to that directly is cleaner.
An earlier revision of this patch made the changes that are now
done in mi_on_normal_stop directly in infrun.c:normal_stop, and so
not having an obvious place to put the new uiout by then, and not
wanting to abuse CLI's uiout, I made a temporary uiout when
necessary.
- Hopefuly the rest of the patch is more or less obvious given the
comments added.
Tested on x86_64 Fedora 20, no regressions.
2014-05-21 Pedro Alves <palves@redhat.com>
PR gdb/13860
* gdbthread.h (struct thread_control_state): New field
`command_interp'.
* infrun.c (follow_fork): Copy the new thread control field to the
child fork thread.
(clear_proceed_status_thread): Clear the new thread control field.
(proceed): Set the new thread control field.
* interps.h (command_interp): Declare.
* interps.c (command_interpreter): New global.
(command_interp): New function.
(interp_exec): Set `command_interpreter' while here.
* cli-out.c (cli_uiout_dtor): New function.
(cli_ui_out_impl): Install it.
* mi/mi-interp.c: Include cli-out.h.
(mi_cmd_interpreter_exec): Add comment.
(restore_current_uiout_cleanup): New function.
(ui_out_free_cleanup): New function.
(mi_on_normal_stop): If finishing an execution command started by
a CLI command, or any kind of breakpoint-like event triggered,
print the stop event to the output (CLI) stream.
* mi/mi-out.c (mi_ui_out_impl): Install NULL `dtor' handler.
2014-05-21 Pedro Alves <palves@redhat.com>
PR gdb/13860
* gdb.mi/mi-cli.exp (line_callee4_next_step): New global.
(top level): Test that output related to execution commands is
sent to the console with CLI commands, but not with MI commands.
Test that breakpoint events are always mirrored to the console.
Also expect the new source line to be output after a "next" in
async mode too. Make it a pass/fail test.
* gdb.mi/mi-solib.exp: Test that the CLI solib event note is
output.
* lib/mi-support.exp (mi_gdb_expect_cli_output): New procedure.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* NEWS: Mention it.
* interps.h (interp_set_logging_ftype): New typedef.
(struct interp_procs): New field set_logging_proc.
(current_interp_set_logging): Declare.
* interps.c (current_interp_set_logging): New function.
* cli/cli-logging.c: Include interps.h.
(set_logging_redirect): Call current_interp_set_logging.
(pop_output_files): Ditto.
(handle_redirections): Ditto, plus skip ui-out redirect if MI.
* mi/mi-console.h (mi_console_set_raw): Declare.
* mi/mi-console.c (mi_console_set_raw): New function.
* mi/mi-interp.c (saved_raw_stdout): New global.
(mi_set_logging): New function.
(_initialize_mi_interp): Add it to interp procs.
* gdb.mi/mi-logging.exp: New file.
commands, even when the current interpreter is MI.
interps.c (interp_set_temp): New function.
interps.h (interp_set_temp): Add prototype.
cli/cli-script.c (restore_interp): New cleanup function.
(read_command_lines): Temporarily override the current interpreter
with CLI and arrange for restoring the original one.
2011-09-12 Pedro Alves <pedro@codesourcery.com>
Matt Rice <ratmice@gmail.com>
PR gdb/13175
* interps.c (struct interp) <interpreter_out>: Delete field.
(interp_new): Remove the data and uiout parameters and adjust.
(interp_set): Only set the current_uiout from the interpreter's
uiout after initializing the interpreter. Adjust call to
init_proc.
(interp_ui_out): Adjust to call procs->ui_out_proc.
(interp_data, interp_name): New.
* interps.h (interp_init_ftype): Add `self' parameter.
(interp_ui_out_ftype): New typedef.
(struct interp_procs) <ui_out_proc>: New method pointer.
(interp_new): Remove the data and uiout parameters.
(interp_data, interp_name): Declare.
* tui/tui-interp.c (tui_init): Adjust prototype.
(tui_ui_out): New.
(_initialize_tui_interp): Install tui_ui_out. Don't instanciate
tui_out here. Adjust call to interp_new.
* tui/tui-io.c (tui_initialize_io): Don't set current_uiout here.
* cli/cli-interp.c (cli_interpreter_init): Adjust prototype.
(cli_ui_out): New.
(_initialize_cli_interp): Install it. Adjust call to interp_new.
* mi/mi-common.h (struct mi_interp) <uiout>: New field.
* mi/mi-interp.c (mi_interpreter_init): Adjust prototype.
Initialize mi->uiout depending on the mi_version as extracted from
the interpreter's name.
(mi_ui_out): New.
(_initialize_mi_interp): Install mi_ui_out. Adjust calls to
interp_new. Don't allocate the ui_out's of the interpreters here.
gdb/testsuite/
2011-09-12 Matt Rice <ratmice@gmail.com>
Pedro Alves <pedro@codesourcery.com>
PR gdb/13175
* gdb.base/interp.exp: New tests.
* gdb.base/interp.c: New file.
* top.c: Include interps.h.
(execute_command): If the target can async, but the interpreter is
in sync mode, synchronously wait for the command to finish before
returning.
(execute_command_to_string): Force the interpreter to sync mode.
* infrun.c: Include interps.h.
(fetch_inferior_event): Don't restore the prompt yet if the
interpreter is in sync mode.
* interps.c (interpreter_async): New global.
* interps.h (interpreter_async): Declare.
* inf-loop.c: Include interps.h.
(inferior_event_handler): Don't print the language change or run
breakpoint commands yet if the interpreter in is sync mode.
* main.c (captured_command_loop): Flip the interpreter to async
mode.
* cli/cli-script.c: Include interps.h.
(execute_user_command, while_command, if_command): Force the
interpreter to sync mode.
* python/python.c: Include interps.h.
(python_command, execute_gdb_command): Force the interpreter to
sync mode.
* main.c (main): Use INTERP_TUI instead of "tui".
Set interpreter to INTERP_INSIGHT when '-w' given.
* interps.h (INTERP_INSIGHT): New define.
* tui/tui-interp.c (_initialize_tui_interp): Use INTERP_TUI instead
of "tui".
Gary Benson
Pedro Alves
Joel Brobecker
Doug Evans
Joel Brobecker
Stan Shebs
Eli Zaretskii
Michael Snyder
Nick Roberts
Vladimir Prus
Daniel Jacobowitz
Andrew Stubbs
Andrew Cagney