We have places where we call a blocking gdb_select expecting that a
Ctrl-C will unblock it. However, if the Ctrl-C is pressed just before
gdb_select, the SIGINT handler runs before gdb_select, and thus
gdb_select won't return.
For example gdb_readline_no_editing:
QUIT;
/* Wait until at least one byte of data is available. Control-C
can interrupt gdb_select, but not fgetc. */
FD_ZERO (&readfds);
FD_SET (fd, &readfds);
if (gdb_select (fd + 1, &readfds, NULL, NULL, NULL) == -1)
and stdio_file_read:
/* For the benefit of Windows, call gdb_select before reading from
the file. Wait until at least one byte of data is available.
Control-C can interrupt gdb_select, but not read. */
{
fd_set readfds;
FD_ZERO (&readfds);
FD_SET (stdio->fd, &readfds);
if (gdb_select (stdio->fd + 1, &readfds, NULL, NULL, NULL) == -1)
return -1;
}
return read (stdio->fd, buf, length_buf);
This is a race classically fixed with either the self-pipe trick, or
by blocking SIGINT and then using pselect instead of select.
Blocking SIGINT most of the time would mean that check_quit_flag (and
thus QUIT) would need to do a syscall every time it is called, which
sounds best avoided, since QUIT is called in many loops. Thus we take
the self-pipe trick route (wrapped in a serial event).
Instead of having all places that need this manually add an extra file
descriptor to the set of gdb_select's watched file descriptors, we
introduce a wrapper, interruptible_select, that does that.
The Windows version of gdb_select actually does not suffer from this,
because mingw-hdep.c:gdb_call_async_signal_handler sets a Windows
event that gdb_select always waits on. So this patch can be seen as
generalization of that technique. We can't remove that extra event
from mingw-hdep.c until we get rid of immediate_quit though.
gdb/ChangeLog:
2016-04-12 Pedro Alves <palves@redhat.com>
* defs.h: Extend QUIT-related comments to mention
interruptible_select.
(quit_serial_event_set, quit_serial_event_clear): Declare.
* event-top.c: Include "ser-event.h" and "gdb_select.h".
(quit_serial_event): New global.
(async_init_signals): Make quit_serial_event.
(quit_serial_event_set, quit_serial_event_clear)
(quit_serial_event_fd, interruptible_select): New functions.
* extension.c (set_quit_flag): Set the quit serial event.
(check_quit_flag): Clear the quit serial event.
* gdb_select.h (interruptible_select): New declaration.
* guile/scm-ports.c (ioscm_input_waiting): Use
interruptible_select instead of gdb_select.
* top.c (gdb_readline_no_editing): Likewise.
* ui-file.c (stdio_file_read): Likewise.
read_command_line is the only caller, and here we can assume we're
reading a regular file, not stdin.
gdb/ChangeLog:
2016-04-12 Pedro Alves <palves@redhat.com>
* top.c (read_command_file): Inline command_loop here.
(command_loop): Delete.
AFAICS, immediate_quit was only needed here nowdays to be able to
interrupt gdb_readline_no_editing.
command_line_input can also take the gdb_readline_wrapper path, but
since that is built on top of the event loop (gdb_select / poll and
asynchronous signal handlers), it can be interrupted.
gdb/ChangeLog:
2016-04-12 Pedro Alves <palves@redhat.com>
* top.c: Include "gdb_select.h".
(gdb_readline_no_editing): Wait for input with gdb_select instead
of blocking in fgetc.
(command_line_input): Don't set immediate_quit.
I didn't manage to usefully split this further into smaller
independent pieces, so:
- Use "struct buffer" more.
- Split out the responsibility of composing a complete command line
from multiple input lines split with backslash
(
E.g.:
(gdb) print \
1 + \
2
$1 = 3
(gdb)
)
to a separate function. Note we don't need the separate
readline_input_state and more_to_come globals at all. They were
just obfuscating the logic.
- Factor out the tricky mostly duplicated code in
command_line_handler and command_line_input.
gdb/ChangeLog
2016-03-09 Pedro Alves <palves@redhat.com>
* event-top.c (more_to_come): Delete.
(struct readline_input_state): Delete.
(readline_input_state): Delete.
(get_command_line_buffer): New function.
(command_handler): Update comments. Don't handle NULL commands
here. Do not execute commented lines.
(command_line_append_input_line): New function.
(handle_line_of_input): New function, partly based on
command_line_handler and command_line_input.
(command_line_handler): Rewrite.
* event-top.h (command_handler): New declaration.
(command_loop): Defer command execution to command_handler.
(command_line_input): Update comments. Simplify, using struct
buffer and handle_line_of_input.
* top.h (struct buffer): New forward declaration.
(handle_line_of_input): New declaration.
There doesn't seem to be much point in trying to reuse this buffer.
Prefer simplicity instead.
(In case you're wondering whether this fixes an off-by-one: linelength
is misnamed; it's really a size including terminating null char.)
gdb/ChangeLog:
2016-03-09 Pedro Alves <palves@redhat.com>
* event-top.c (command_line_handler): Use xfree + xstrdup instead
of xrealloc + strcpy.
* main.c (captured_main): Use xstrdup instead of xmalloc plus
manual clear.
* top.c (saved_command_line): Rewrite comment.
(saved_command_line_size): Delete.
(command_line_input): Use xfree + xstrdup instead of xrealloc +
strcpy.
* top.h (saved_command_line_size): Delete declaration.
gdb/ChangeLog:
2016-03-09 Pedro Alves <palves@redhat.com>
* common/buffer.h (buffer_grow_char): New function.
* top.c: Include buffer.h.
(gdb_readline_no_editing): Rename 'prompt_arg' parameter to
'prompt'. Use struct buffer instead of xrealloc.
Name this such that it's clearer that this is not a wrapper for the
real readline, but instead a replacement that provides no command line
editing features.
gdb/ChangeLog:
2016-03-09 Pedro Alves <palves@redhat.com>
* defs.h (gdb_readline): Delete declaration.
* top.c (gdb_readline): Rename to ...
(gdb_readline_no_editing): ... this, and make static.
The comments and existence of this global are a bit of misleading
obfuscation, since this is only ever used to print the prompt
annotation, and never changes. Just hardcode "prompt" where
necessary, as done for most other annotations.
gdb/ChangeLog:
2016-03-09 Pedro Alves <palves@redhat.com>
* event-top.c (async_annotation_suffix): Delete.
(top_level_prompt, command_line_handler): Don't use
'async_annotation_suffix' and simplify.
* event-top.h (async_annotation_suffix): Delete declaration.
(init_main): Remove reference to 'async_annotation_suffix'.
I checked, and Insight doesn't set this.
gdb/ChangeLog:
2016-03-09 Pedro Alves <palves@redhat.com>
* top.c (window_hook): Delete.
(command_loop): Remove references to window_hook.
gdb/ChangeLog:
* top.c (print_gdb_version): Change copyright year in version
message.
gdb/gdbserver/ChangeLog:
* gdbreplay.c (gdbreplay_version): Change copyright year in
version message.
* server.c (gdbserver_version): Likewise.
2015-12-18 Sandra Loosemore <sandra@codesourcery.com>
gdb/
* event-top.c (command_handler): Don't require stdin to be a tty
for call to reinitialize_more_filter.
* top.c (command_loop): Likewise.
This patch makes the execution control code use largely the same
mechanisms in both sync- and async-capable targets. This means using
continuations and use the event loop to react to target events on sync
targets as well. The trick is to immediately mark infrun's event loop
source after resume instead of calling wait_for_inferior. Then
fetch_inferior_event is adjusted to do a blocking wait on sync
targets.
Tested on x86_64 Fedora 20, native and gdbserver, with and without
"maint set target-async off".
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_do_actions_1, until_break_command): Don't
check whether the target can async.
* inf-loop.c (inferior_event_handler): Only call target_async if
the target can async.
* infcall.c: Include top.h and interps.h.
(run_inferior_call): For the interpreter to sync mode while
running the infcall. Call wait_sync_command_done instead of
wait_for_inferior plus normal_stop.
* infcmd.c (prepare_execution_command): Don't check whether the
target can async when running in the foreground.
(step_1): Delete synchronous case handling.
(step_once): Always install a continuation, even in sync mode.
(until_next_command, finish_forward): Don't check whether the
target can async.
(attach_command_post_wait, notice_new_inferior): Always install a
continuation, even in sync mode.
* infrun.c (mark_infrun_async_event_handler): New function.
(proceed): In sync mode, mark infrun's event source instead of
waiting for events here.
(fetch_inferior_event): If the target can't async, do a blocking
wait.
(prepare_to_wait): In sync mode, mark infrun's event source.
(infrun_async_inferior_event_handler): No longer bail out if the
target can't async.
* infrun.h (mark_infrun_async_event_handler): New declaration.
* linux-nat.c (linux_nat_wait_1): Remove calls to
set_sigint_trap/clear_sigint_trap.
(linux_nat_terminal_inferior): No longer check whether the target
can async.
* mi/mi-interp.c (mi_on_sync_execution_done): Update and simplify
comment.
(mi_execute_command_input_handler): No longer check whether the
target is async. Update and simplify comment.
* target.c (default_target_wait): New function.
* target.h (struct target_ops) <to_wait>: Now defaults to
default_target_wait.
(default_target_wait): Declare.
* top.c (wait_sync_command_done): New function, factored out from
...
(maybe_wait_sync_command_done): ... this.
* top.h (wait_sync_command_done): Declare.
* target-delegates.c: Regenerate.
This patch fixes the following bug in TUI:
(gdb) break foo
No symbol table is loaded. Use the "file" command.
Make breakpoint pending on future shared library load? (y or [n]) <ENTER>
By submitting an empty command line to a secondary prompt, the line
corresponding to the secondary prompt is undesirably cleared and
overwritten. Outside of a secondary prompt, clearing the prompt line
after submitting an empty command line is intended behavior which
complements GDB's repeat-command shorthand. But inside a secondary
prompt, this behavior is undesired since the shorthand is not applicable
in that case. We should retain the secondary-prompt line even when it's
given no input.
This patch makes sure that a prompt that was given an empty command line
is cleared and overwritten only if it's not a secondary prompt. To
acheive this, a new predicate is defined which informs us whether the
current input handler is a secondary prompt.
gdb/ChangeLog:
* top.h (gdb_in_secondary_prompt_p): Declare.
* top.c (gdb_secondary_prompt_depth): Define.
(gdb_in_secondary_prompt_p): Define.
(gdb_readline_wrapper_cleanup): Decrement
gdb_secondary_prompt_depth.
(gdb_readline_wrapper): Increment gdb_secondary_prompt_depth.
* tui/tui-io.c (tui_getc): Don't clear the prompt line if we
are in a secondary prompt.
The get_frame_language feels like it would be more at home in frame.c
rather than in stack.c, while the declaration, that is currently in
language.h can be moved into frame.h to match.
A couple of new includes are added, but otherwise no substantial change
here.
gdb/ChangeLog:
* stack.c (get_frame_language): Moved ...
* frame.c (get_frame_language): ... to here.
* language.h (get_frame_language): Declaration moved to frame.h.
* frame.h: Add language.h include, for language enum.
(get_frame_language): Declaration moved from language.h.
* language.c: Add frame.h include.
* top.c: Add frame.h include.
* symtab.h (struct obj_section): Declare.
(struct cmd_list_element): Declare.
As part of a drive to remove deprecated_safe_get_selected_frame, make
the get_frame_language function take a frame parameter. Given the name
of the function this actually seems to make a lot of sense.
The task of fetching a suitable frame is then passed to the calling
functions. For get_frame_language there are not many callers, these are
updated to get the selected frame in a suitable way.
gdb/ChangeLog:
* language.c (show_language_command): Find selected frame before
asking for the language of that frame.
(set_language_command): Likewise.
* language.h (get_frame_language): Add frame parameter.
* stack.c (get_frame_language): Add frame parameter, assert
parameter is not NULL, update comment and reindent.
* top.c (check_frame_language_change): Pass the selected frame
into get_frame_language.
When exiting GDB -- whether it's via the "quit" command, via a SIGTERM,
or otherwise -- we should leave the terminal in the state we acquired
it. To that end, we have to undo any modifications that may have been
made by the TUI (ncurses) or by the CLI (readline).
Tested on x86_64 Debian Stretch.
gdb/ChangeLog:
* top.c: Include "tui/tui.h".
(undo_terminal_modifications_before_exit): New static function.
(quit_force): Use it.
gdb/testsuite/ChangeLog:
* gdb.base/batch-preserve-term-settings.exp
(test_terminal_settings_preserved_after_cli_exit): New test.
This is a straightforward replacement of the TUI's use of the
aforementioned hook with the register_changed observer. Since this was
the only user of the hook, this patch also removes the hook.
gdb/ChangeLog:
* defs.h (deprecated_register_changed_hook): Remove prototype.
* interps.c (clear_iterpreter_hooks): Remove reference to
deprecated_register_changed_hook.
* top.c (deprecated_register_changed_hook): Remove prototype.
* valops.c (value_assign): Remove reference to
deprecated_register_changed_hook.
* tui/tui-hooks.c (tui_register_changed): Add parameter "frame".
Add comment documenting the function.
(tui_register_changed_observer): Define.
(tui_install_hooks): Remove reference to
deprecated_register_changed_hook. Set
tui_register_changed_observer.
(tui_remove_hooks): Remove reference to
deprecated_register_changed_hook. Unset
tui_register_changed_observer.
This patch implements the new option "history remove-duplicates", which
controls the removal of duplicate history entries ("off" by default).
The motivation for this option is to be able to reduce the prevalence of
basic commands such as "up" and "down" in the history file. These
common commands crowd out more unique commands in the history file (when
the history file has a fixed size), and they make navigation of the
history file via ^P, ^N and ^R more inconvenient.
The option takes an integer denoting the number of history entries to
look back at for a history entry that is a duplicate of the latest one.
"history remove-duplicates 1" is equivalent to bash's ignoredups option,
and "history remove-duplicates unlimited" is equivalent to bash's
erasedups option.
[ I decided to go with this integer approach instead of a tri-state enum
because it's slightly more flexible and seemingly more intuitive than
leave/erase/ignore. ]
gdb/ChangeLog:
* NEWS: Mention the new option "history remove-duplicates".
* top.c (history_remove_duplicates): New static variable.
(show_history_remove_duplicates): New static function.
(gdb_add_history): Conditionally remove duplicate history
entries.
(init_main): Add "history remove-duplicates" option.
gdb/doc/ChangeLog:
* gdb.texinfo (Command History): Document the new option
"history remove-duplicates".
gdb/testsuite/ChangeLog:
* gdb.base/history-duplicates.exp: New test.
The test
test_histsize_history_setting "99999999999999999999999999999999999" "unlimited"
was failing on i686 because the condition in init_history() for
determining whether to map a large GDBHISTSIZE value to infinity was
long var = strtol (tmpenv);
if (var > INT_MAX)
history_size = unlimited;
but this condition is never true on i686 because INT_MAX == LONG_MAX.
So in order to properly map large out-of-range values of GDBHISTSIZE to
infinity on targets where LONG_MAX > INT_MAX as well as on i686, we have
to instead change the above condition to
if (var > INT_MAX
|| (var == INT_MAX && errno == ERANGE))
history_size = unlimited;
gdb/ChangeLog:
* top.c (init_history): Look at errno after calling strtol to
properly map large GDBHISTSIZE values to infinity.
When GDB reads a nonsensical value for the GDBHISTSIZE environment
variable, i.e. one that is non-numeric or negative, GDB then sets its
history size to 0. This behavior is annoying and also inconsistent
with the behavior of bash.
This patch makes the behavior of invalid GDBHISTSIZE consistent with how
bash handles HISTSIZE. When we encounter a null or out-of-range
GDBHISTSIZE (outside of [0, INT_MAX]) we now set the history size to
unlimited instead of 0. When we encounter a non-numeric GDBHISTSIZE we
do nothing.
gdb/ChangeLog:
PR gdb/16999
* NEWS: Mention new GDBHISTSIZE behavior.
* top.c (init_history): For null or out-of-range GDBHISTSIZE,
set history size to unlimited. Ignore non-numeric GDBHISTSIZE.
gdb/doc/ChangeLog:
PR gdb/16999
* gdb.texinfo (Command History): Mention new GDBHISTSIZE
behavior.
gdb/testsuite/ChangeLog:
PR gdb/16999
* gdb.base/gdbhistsize-history.exp: New test.
The HISTSIZE environment variable is generally expected to be read by
shells, not by applications. Some distros for example globally export
HISTSIZE in /etc/profile -- with the intention that it only affects
shells -- and by doing so it renders useless GDB's own mechanism for
setting the history size via .gdbinit. Also, annoyances may arise when
HISTSIZE is not interpreted the same way by the shell and by GDB, e.g.
PR gdb/16999. That can always be fixed on a shell-by-shell basis but it
may be impossible to be consistent with the behavior of all shells at
once. Finally it just makes sense to not confound shell environment
variables with application environment variables.
gdb/ChangeLog:
* NEWS: Mention that GDBHISTSIZE is read instead of HISTSIZE.
* top.c (init_history): Read from GDBHISTSIZE instead of
HISTSIZE.
(init_main): Refer to GDBHISTSIZE instead of HISTSIZE.
gdb/doc/ChangeLog:
* gdb.texinfo (Command History): Replace occurrences of HISTSIZE
with GDBHISTSIZE.
gdb/testsuite/ChangeLog:
* gdb.base/gdbinit-history.exp: Replace occurrences of HISTSIZE
with GDBHISTSIZE.
* gdb.base/readline.exp: Likewise.
We still do not handle "set history size unlimited" correctly. In
particular, after writing to the history file, we truncate the history
even if it is unlimited.
This patch makes sure that we do not call history_truncate_file() if the
history is not stifled (i.e. if it's unlimited). This bug causes the
history file to be truncated to zero on exit when one has "set history
size unlimited" in their gdbinit file. Although this code exists in GDB
7.8, the bug is masked by a pre-existing bug that's been only fixed in
GDB 7.9 (PR gdb/17820).
gdb/ChangeLog:
* top.c (gdb_safe_append_history): Do not call
history_truncate_file if the history is not stifled.
gdb/testsuite/ChangeLog:
* gdb.base/gdbinit-history.exp: Add test case to check that
an unlimited history file does not get truncated on exit.
This patch is a comprehensive fix for PR 17820 which reports that
using "set history size unlimited" inside one's gdbinit file doesn't
really work.
There are three small changes in this patch. The most important change
this patch makes is to decode the argument of the "size" subcommand
using add_setshow_zuinteger_unlimited_cmd() instead of using
add_setshow_uinteger_cmd(). The new decoder takes an int * and maps
unlimited to -1 whereas the old decoder takes an unsigned int * and maps
unlimited to UINT_MAX. Using the new decoder simplifies our handling of
unlimited and makes it easier to interface with readline which itself
expects a signed-int history size.
The second change is the factoring of the [stifle|unstifle]_history logic
into a common function which is now used by both init_history() and
set_history_size_command(). This is technically the change that fixes
the PR itself.
Thirdly, this patch initializes history_size_setshow_var to -2 to mean
that the variable has not been set yet. Now init_history() tests for -2
instead of 0 to determine whether to give the variable a default value.
This means that having "set history size 0" in one's gdbinit file will
actually keep the history size at 0 and not reset it to 256.
gdb/ChangeLog:
PR gdb/17820
* top.c (history_size_setshow_var): Change type to signed.
Initialize to -2. Update documentation.
(set_readline_history_size): Define.
(set_history_size_command): Use it. Remove logic for handling
out-of-range sizes.
(init_history): Use set_readline_history_size(). Test for a
value of -2 instead of 0 when determining whether to set a
default history size.
(init_main): Decode the argument of the "size" command as a
zuinteger_unlimited.
gdb/testsuite/ChangeLog:
PR gdb/17820
* gdb.base/gdbinit-history.exp: New test.
* gdb.base/gdbinit-history/unlimited/.gdbinit: New file.
* gdb.base/gdbinit-history/zero/.gdbinit: New file.
This hook is no longer used, and can therefore be eliminated.
gdb/ChangeLog:
* defs.h (deprecated_init_ui_hook): Delete. Remove associated
comment.
* top.c (deprecated_init_ui_hook): Delete.
(gdb_init): Remove handling of deprecated_init_ui_hook.
* interps.c (clear_interpreter_hooks): Remove handling of
deprecated_init_ui_hook.
* main.c (captured_main): Update comment.
We no longer need it as we handle SIGWINCH ourselves. Also move the
call to init_page_info() from initialize_utils() to the latter
function's only caller, gdb_init().
gdb/ChangeLog:
* utils.c (init_page_info): Set rl_catch_sigwinch to zero.
(initialize_utils): Move call of init_page_info() to ...
* top.c (gdb_init): ... here.
All callers of target_async pass it the same callback
(inferior_event_handler). Since both common code and target backends
need to be able to put the target in and out of target async mode at
any given time, there's really no way that a different callback could
be passed. This commit simplifies things, and removes the indirection
altogether. Bonus: with this, gdb's target_async method ends up with
the same signature as gdbserver's.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
2015-03-25 Pedro Alves <palves@redhat.com>
* target.h <to_async>: Replace 'callback' and 'context' parameters
with boolean 'enable' parameter.
(target_async): Replace CALLBACK and CONTEXT parameters with
boolean ENABLE parameter.
* inf-loop.c (inferior_event_handler): Adjust.
* linux-nat.c (linux_nat_attach, linux_nat_resume)
(linux_nat_resume): Adjust.
(async_client_callback, async_client_context): Delete.
(handle_target_event): Call inferior_event_handler directly.
(linux_nat_async): Replace 'callback' and 'context' parameters
with boolean 'enable' parameter. Adjust. Remove references to
async_client_callback and async_client_context.
(linux_nat_close): Adjust.
* record-btrace.c (record_btrace_async): Replace 'callback' and
'context' parameters with boolean 'enable' parameter. Adjust.
(record_btrace_resume): Adjust.
* record-full.c (record_full_async): Replace 'callback' and
'context' parameters with boolean 'enable' parameter. Adjust.
(record_full_resume, record_full_core_resume): Adjust.
* remote.c (struct remote_state) <async_client_callback,
async_client_context>: Delete fields.
(remote_start_remote, extended_remote_attach_1, remote_resume)
(extended_remote_create_inferior): Adjust.
(remote_async_serial_handler): Call inferior_event_handler
directly.
(remote_async): Replace 'callback' and 'context' parameters with
boolean 'enable' parameter. Adjust.
* top.c (gdb_readline_wrapper_cleanup, gdb_readline_wrapper):
Adjust.
* target-delegates.c: Regenerate.
This patch splits the TRY_CATCH macro into three, so that we go from
this:
~~~
volatile gdb_exception ex;
TRY_CATCH (ex, RETURN_MASK_ERROR)
{
}
if (ex.reason < 0)
{
}
~~~
to this:
~~~
TRY
{
}
CATCH (ex, RETURN_MASK_ERROR)
{
}
END_CATCH
~~~
Thus, we'll be getting rid of the local volatile exception object, and
declaring the caught exception in the catch block.
This allows reimplementing TRY/CATCH in terms of C++ exceptions when
building in C++ mode, while still allowing to build GDB in C mode
(using setjmp/longjmp), as a transition step.
TBC, after this patch, is it _not_ valid to have code between the TRY
and the CATCH blocks, like:
TRY
{
}
// some code here.
CATCH (ex, RETURN_MASK_ERROR)
{
}
END_CATCH
Just like it isn't valid to do that with C++'s native try/catch.
By switching to creating the exception object inside the CATCH block
scope, we can get rid of all the explicitly allocated volatile
exception objects all over the tree, and map the CATCH block more
directly to C++'s catch blocks.
The majority of the TRY_CATCH -> TRY+CATCH+END_CATCH conversion was
done with a script, rerun from scratch at every rebase, no manual
editing involved. After the mechanical conversion, a few places
needed manual intervention, to fix preexisting cases where we were
using the exception object outside of the TRY_CATCH block, and cases
where we were using "else" after a 'if (ex.reason) < 0)' [a CATCH
after this patch]. The result was folded into this patch so that GDB
still builds at each incremental step.
END_CATCH is necessary for two reasons:
First, because we name the exception object in the CATCH block, which
requires creating a scope, which in turn must be closed somewhere.
Declaring the exception variable in the initializer field of a for
block, like:
#define CATCH(EXCEPTION, mask) \
for (struct gdb_exception EXCEPTION; \
exceptions_state_mc_catch (&EXCEPTION, MASK); \
EXCEPTION = exception_none)
would avoid needing END_CATCH, but alas, in C mode, we build with C90,
which doesn't allow mixed declarations and code.
Second, because when TRY/CATCH are wired to real C++ try/catch, as
long as we need to handle cleanup chains, even if there's no CATCH
block that wants to catch the exception, we need for stop at every
frame in the unwind chain and run cleanups, then rethrow. That will
be done in END_CATCH.
After we require C++, we'll still need TRY/CATCH/END_CATCH until
cleanups are completely phased out -- TRY/CATCH in C++ mode will
save/restore the current cleanup chain, like in C mode, and END_CATCH
catches otherwise uncaugh exceptions, runs cleanups and rethrows, so
that C++ cleanups and exceptions can coexist.
IMO, this still makes the TRY/CATCH code look a bit more like a
newcomer would expect, so IMO worth it even if we weren't considering
C++.
gdb/ChangeLog.
2015-03-07 Pedro Alves <palves@redhat.com>
* common/common-exceptions.c (struct catcher) <exception>: No
longer a pointer to volatile exception. Now an exception value.
<mask>: Delete field.
(exceptions_state_mc_init): Remove all parameters. Adjust.
(exceptions_state_mc): No longer pop the catcher here.
(exceptions_state_mc_catch): New function.
(throw_exception): Adjust.
* common/common-exceptions.h (exceptions_state_mc_init): Remove
all parameters.
(exceptions_state_mc_catch): Declare.
(TRY_CATCH): Rename to ...
(TRY): ... this. Remove EXCEPTION and MASK parameters.
(CATCH, END_CATCH): New.
All callers adjusted.
gdb/gdbserver/ChangeLog:
2015-03-07 Pedro Alves <palves@redhat.com>
Adjust all callers of TRY_CATCH to use TRY/CATCH/END_CATCH
instead.
More preparation for running the TRY_CATCH->TRY/CATCH conversion
script.
gdb/ChangeLog:
2015-03-07 Tom Tromey <tromey@redhat.com>
* top.c (quit_force): Inline and delete DO_TRY, DO_PRINT_EX.
This patch renames symbols that happen to have names which are
reserved keywords in C++.
Most of this was generated with Tromey's cxx-conversion.el script.
Some places where later hand massaged a bit, to fix formatting, etc.
And this was rebased several times meanwhile, along with re-running
the script, so re-running the script from scratch probably does not
result in the exact same output. I don't think that matters anyway.
gdb/
2015-02-27 Tom Tromey <tromey@redhat.com>
Pedro Alves <palves@redhat.com>
Rename symbols whose names are reserved C++ keywords throughout.
gdb/gdbserver/
2015-02-27 Tom Tromey <tromey@redhat.com>
Pedro Alves <palves@redhat.com>
Rename symbols whose names are reserved C++ keywords throughout.
Even with the previous patch installed, we'll still see
sigall-reverse.exp occasionally fail. The problem is that the event
loop's event handling processing is done in two steps:
#1 - poll all event sources, and push new event objects to the event
queue, until all event sources are drained.
#2 - go through the event queue, processing each event object at a
time. For each event, call the associated callback, and deletes the
event object from the queue.
and then bad things happen if between #1 and #2 something decides that
events from an event source that has already queued events shouldn't
be processed yet. To do that, we either remove the event source from
the list of event sources, or clear its "have events" flag. However,
if an event for that source has meanwhile already been pushed in the
event queue, #2 will still process it and call the associated
callback...
One way to fix it that I considered was to do something to the event
objects already in the event queue when an event source is no longer
interesting. But then I couldn't find any good reason for the
two-step process in the first place. It's much simpler (and less
code) to call the event source callbacks as we poll the sources and
find events.
Tested on x86-64 Fedora 20, native and gdbserver.
gdb/
2015-02-03 Pedro Alves <palves@redhat.com>
* event-loop.c: Don't declare nor define a queue type for
gdb_event_p.
(event_queue): Delete.
(create_event, create_file_event, gdb_event_xfree)
(initialize_event_loop, process_event): Delete.
(gdb_do_one_event): Return as soon as one event is handled.
(handle_file_event): Change prototype. Used the passed in
file_handler pointer and ready_mask instead of looping over all
file handlers.
(gdb_wait_for_event): Update the poll/select timeouts before
blocking. Run event handlers directly instead of queueing events.
Return as soon as one event is handled.
(struct async_event_handler_data): Delete.
(invoke_async_event_handler): Delete.
(check_async_event_handlers): Change return type to int. Run
event handlers directly instead of queueing events. Return as
soon as one event is handled.
(handle_timer_event): Delete.
(update_wait_timeout): New function, factored out from
poll_timers.
(poll_timers): Reimplement.
* event-loop.h (initialize_event_loop): Delete declaration.
* top.c (gdb_init): Don't call initialize_event_loop.
This copies a lot of code from readline, but this is temporary.
Readline currently doesn't export what we need.
The plan is to have something that has been working for awhile,
and then we'll have a complete story to present to the readline
maintainers.
gdb/ChangeLog:
* cli-out.c: #include completer.h, readline/readline.h.
(cli_mld_crlf, cli_mld_putch, cli_mld_puts): New functions.
(cli_mld_flush, cld_mld_erase_entire_line): Ditto.
(cli_mld_beep, cli_mld_read_key, cli_display_match_list): Ditto.
* cli-out.h (cli_display_match_list): Declare.
* completer.c (MB_INVALIDCH, MB_NULLWCH): New macros.
(ELLIPSIS_LEN): Ditto.
(gdb_get_y_or_n, gdb_display_match_list_pager): New functions.
(gdb_path_isdir, gdb_printable_part, gdb_fnwidth): Ditto.
(gdb_fnprint, gdb_print_filename): Ditto.
(gdb_complete_get_screenwidth, gdb_display_match_list_1): Ditto.
(gdb_display_match_list): Ditto.
* completer.h (mld_crlf_ftype, mld_putch_ftype): New typedefs.
(mld_puts_ftype, mld_flush_ftype, mld_erase_entire_line_ftype): Ditto.
(mld_beep_ftype, mld_read_key_ftype): Ditto.
(match_list_displayer): New struct.
(gdb_display_match_list): Declare.
* top.c (init_main): Set rl_completion_display_matches_hook.
* tui/tui-io.c: #include completer.h.
(printable_part, PUTX, print_filename, get_y_or_n): Delete.
(tui_mld_crlf, tui_mld_putch, tui_mld_puts): New functions.
(tui_mld_flush, tui_mld_erase_entire_line, tui_mld_beep): Ditto.
(tui_mld_getc, tui_mld_read_key): Ditto.
(tui_rl_display_match_list): Rewrite.
(tui_handle_resize_during_io): New arg for_completion. All callers
updated.
This patch makes readline append new history lines to the GDB history
file on exit instead of overwriting the entire history file on exit.
This change allows us to run multiple simultaneous GDB sessions without
having each session overwrite the added history of each other session on
exit.
Care must be taken to ensure that the history file doesn't get corrupted
when multiple GDB processes are trying to simultaneously append to and
then truncate it. Safety is achieved in such a situation by using an
intermediate local history file to mutually exclude multiple processes
from simultaneously performing write operations on the global history
file.
gdb/ChangeLog:
* top.h (gdb_add_history): Declare.
* top.c (command_count): New variable.
(gdb_add_history): New function.
(gdb_safe_append_history): New static function.
(quit_force): Call it.
(command_line_input): Use gdb_add_history instead of
add_history.
* event-top.c (command_line_handler): Likewise.
Currently when we start an inferior we have the inferior inherit our
terminal state. Under TUI, our terminal is highly modified by ncurses
and readline. So when starting an inferior under TUI, the inferior will
have a highly modified terminal state which will interfere with standard
I/O. For example,
$ gdb gdb
(gdb) break main
(gdb) run
(gdb) print puts ("a\nb")
a
b
$1 = 4
(gdb) [enter TUI mode]
(gdb) run
(gdb) [exit TUI mode]
(gdb) print puts ("a\nb")
a
b
$2 = 4
(gdb) print puts ("a\r\nb\r")
a
b
$3 = 6
As you can see, when we start the inferior under the regular interface,
puts() prints the text properly. But when we start the inferior under
TUI, puts() does not print the text properly. This is because when we
start the inferior under TUI it inherits our current terminal state
which has been modified by ncurses to, among other things, require an
explicit \r\n to print a new line. As a result the inferior performs
standard I/O in an unexpected way.
Because of this discrepancy, it doesn't seem like a good idea to have
the inferior inherit our _current_ terminal state for it may have been
modified by readline and/or ncurses. Instead, we should have the
inferior inherit a pristine snapshot of our terminal state taken before
readline or ncurses have had a chance to alter it. This enables the
inferior to run in a more accurate way, more closely mimicking the
program's behavior had it run standalone. And it fixes the above
mentioned issue.
Tested on x86_64-unknown-linux-gnu.
gdb/ChangeLog:
* terminal.h (set_initial_gdb_ttystate): Declare.
* inflow.c (initial_gdb_ttystate): New static variable.
(set_initial_gdb_ttystate): New setter.
(child_terminal_init_with_pgrp): Copy initial_gdb_ttystate
instead of our current terminal state.
* top.c (gdb_init): Call set_initial_gdb_ttystate.
The type of the function pointer PyOS_ReadlineFunctionPointer (part of the
Python C API), which we use, slightly changed starting with Python 3.4. The
signature went from
PyAPI_DATA(char) *(*PyOS_ReadlineFunctionPointer)(FILE *, FILE *, char *);
to
PyAPI_DATA(char) *(*PyOS_ReadlineFunctionPointer)(FILE *, FILE *, const char *);
The parameter that changed is the prompt text.
This commits adjust gdb accordingly by making the prompt_arg parameter
const, as well as the fallouts of that. I needed to rework how
annotations are added to the prompt, since the it is now const. If
annotations are enabled, it will make a copy of the prompt overwrite the
prompt variable that is used throughout the function. Otherwise, no copy
is done and the original prompt_arg value is passed.
I changed the signature of deprecated_readline_hook. I would've changed any
user of it, but it seems like nothing is using it,
Built-tested with python 2.7.x, 3.3.y and 3.4.z.
gdb/ChangeLog:
* defs.h (gdb_readline): Constify argument.
(gdb_readline_wrapper): Same.
(command_line_input): Same.
(deprecated_readline_hook): Same.
* top.c (deprecated_readline_hook): Same.
(gdb_readline): Same.
(gdb_readline_wrapper): Same.
(command_line_input): Constify argument. Pass prompt to
called functions instead of local_prompt, overwriting prompt
if using annotations.
* event-top.h (display_gdb_prompt): Constify argument.
* event-top.c (display_gdb_prompt): Same.
* python/py-gdb-readline.c (gdbpy_readline_wrapper): Constify
argument if building with Python 3.4 and up.
Signed-off-by: Simon Marchi <simon.marchi@ericsson.com>
This is more of a readline/terminal issue than a Python one.
PR17372 is a regression in 7.8 caused by the fix for PR17072:
commit 0017922d02
Author: Pedro Alves <palves@redhat.com>
Date: Mon Jul 14 19:55:32 2014 +0100
Background execution + pagination aborts readline/gdb
gdb_readline_wrapper_line removes the handler after a line is
processed. Usually, we'll end up re-displaying the prompt, and that
reinstalls the handler. But if the output is coming out of handling
a stop event, we don't re-display the prompt, and nothing restores the
handler. So the next input wakes up the event loop and calls into
readline, which aborts.
...
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c (gdb_readline_wrapper_line): Tweak comment.
(gdb_readline_wrapper_cleanup): If readline is enabled, reinstall
the input handler callback.
The problem is that installing the input handler callback also preps
the terminal, putting it in raw mode and with echo disabled, which is
bad if we're going to call a command that assumes cooked/canonical
mode, and echo enabled, like in the case of the PR, Python's
interactive shell. Another example I came up with that doesn't depend
on Python is starting a subshell with "(gdb) shell /bin/sh" from a
multi-line command. Tests covering both these examples are added.
The fix is to revert the original fix for PR gdb/17072, and instead
restore the callback handler after processing an asynchronous target
event.
Furthermore, calling rl_callback_handler_install when we already have
some input in readline's line buffer discards that input, which is
obviously a bad thing to do while the user is typing. No specific
test is added for that, because I first tried calling it even if the
callback handler was still installed and that resulted in hundreds of
failures in the testsuite.
gdb/
2014-10-29 Pedro Alves <palves@redhat.com>
PR python/17372
* event-top.c (change_line_handler): Call
gdb_rl_callback_handler_remove instead of
rl_callback_handler_remove.
(callback_handler_installed): New global.
(gdb_rl_callback_handler_remove, gdb_rl_callback_handler_install)
(gdb_rl_callback_handler_reinstall): New functions.
(display_gdb_prompt): Call gdb_rl_callback_handler_remove and
gdb_rl_callback_handler_install instead of
rl_callback_handler_remove and rl_callback_handler_install.
(gdb_disable_readline): Call gdb_rl_callback_handler_remove
instead of rl_callback_handler_remove.
* event-top.h (gdb_rl_callback_handler_remove)
(gdb_rl_callback_handler_install)
(gdb_rl_callback_handler_reinstall): New declarations.
* infrun.c (reinstall_readline_callback_handler_cleanup): New
cleanup function.
(fetch_inferior_event): Install it.
* top.c (gdb_readline_wrapper_line) Call
gdb_rl_callback_handler_remove instead of
rl_callback_handler_remove.
(gdb_readline_wrapper_cleanup): Don't call
rl_callback_handler_install.
gdb/testsuite/
2014-10-29 Pedro Alves <palves@redhat.com>
PR python/17372
* gdb.python/python.exp: Test a multi-line command that spawns
interactive Python.
* gdb.base/multi-line-starts-subshell.exp: New file.
Doing:
gdb --pid=PID -ex run
Results in GDB getting a SIGTTIN, and thus ending stopped. That's
usually indicative of a missing target_terminal_ours call.
E.g., from the PR:
$ sleep 1h & p=$!; sleep 0.1; gdb -batch sleep $p -ex run
[1] 28263
[1] Killed sleep 1h
[2]+ Stopped gdb -batch sleep $p -ex run
The workaround is doing:
gdb -ex "attach $PID" -ex "run"
instead of
gdb [-p] $PID -ex "run"
With the former, gdb waits for the attach command to complete before
moving on to the "run" command, because the interpreter is in sync
mode at this point, within execute_command. But for the latter,
attach_command is called directly from captured_main, and thus misses
that waiting. IOW, "run" is running before the attach continuation
has run, before the program stops and attach completes. The broken
terminal settings are just one symptom of that. Any command that
queries or requires input results in the same.
The fix is to wait in catch_command_errors (which is specific to
main.c nowadays), just like we wait in execute_command.
gdb/ChangeLog:
2014-09-11 Pedro Alves <palves@redhat.com>
PR gdb/17347
* main.c: Include "infrun.h".
(catch_command_errors, catch_command_errors_const): Wait for the
foreground command to complete.
* top.c (maybe_wait_sync_command_done): New function, factored out
from ...
(maybe_wait_sync_command_done): ... here.
* top.h (maybe_wait_sync_command_done): New declaration.
gdb/testsuite/ChangeLog:
2014-09-11 Pedro Alves <palves@redhat.com>
PR gdb/17347
* lib/gdb.exp (gdb_spawn_with_cmdline_opts): New procedure.
* gdb.base/attach.exp (test_command_line_attach_run): New
procedure.
(top level): Call it.
If a pagination prompt triggers while the target is running, and the
target exits before the user responded to the pagination query, this
happens:
Starting program: foo
---Type <return> to continue, or q <return> to quit---No unwaited-for children left.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
(gdb) Couldn't get registers: No such process.
(gdb)
To reiterate, the user hasn't replied to the pagination prompt above.
A pagination query nests an event loop (in gdb_readline_wrapper). In
async mode, in addition to stdin and signal handlers, we'll have the
target also installed in the event loop still. So if the target
reports an event, that wakes up the nested event loop, which calls
into fetch_inferior_event etc. to handle the event which generates
further output, all while we should be waiting for pagination
confirmation...
(TBC, any target event that generates output ends up spuriously waking
up the pagination, though exits seem to be the worse kind.)
I've played with a couple different approaches to fixing this, while
at the same time trying to avoid being invasive. Both revolve around
not listening to target events while in a pagination prompt (doing
anything else I think would be a much bigger change).
The approach taken just removes the target from the event loop while
within gdb_readline_wrapper. The other approach used gdb_select
directly, with only input_fd installed, but that had the issue that it
didn't handle the async signal handlers, and turned out to be a bit
more code than the first version.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c: Include "inf-loop.h".
(struct gdb_readline_wrapper_cleanup) <target_is_async_orig>: New
field.
(gdb_readline_wrapper_cleanup): Make the target async again, if it
was async before.
(gdb_readline_wrapper): Store whether the target is async, and
make it sync.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-inferior-exit.c: New file.
* gdb.base/paginate-inferior-exit.exp: New file.
If pagination occurs as result of output sent as response to a target
event while the target is executing in the background, subsequent
input aborts readline/gdb:
$ gdb program
...
(gdb) continue&
Continuing.
(gdb)
---Type <return> to continue, or q <return> to quit---
*return*
---Type <return> to continue, or q <return> to quit---
Breakpoint 2, after_sleep () at paginate-bg-execution.c:21
---Type <return> to continue, or q <return> to quit---
21 return; /* after sleep */
p 1
readline: readline_callback_read_char() called with no handler!
*abort/SIGABRT*
$
gdb_readline_wrapper_line removes the handler after a line is
processed. Usually, we'll end up re-displaying the prompt, and that
reinstalls the handler. But if the output is coming out of handling
a stop event, we don't re-display the prompt, and nothing restores the
handler. So the next input wakes up the event loop and calls into
readline, which aborts.
We should do better with the prompt handling while the target is
running (I think we should coordinate with readline, and
hide/redisplay it around output), but that's a more invasive change
better done post 7.8, so this patch is conservative and just
reinstalls the handler as soon as we're out of the readline line
callback.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c (gdb_readline_wrapper_line): Tweak comment.
(gdb_readline_wrapper_cleanup): If readline is enabled, reinstall
the input handler callback.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-bg-execution.c: New file.
* gdb.base/paginate-bg-execution.exp: New file.
Currently there are many calls to help_list that pass the constant -1
as the "class" value. However, the parameter is declared as being of
type enum command_class, and uses of the constant violate this
abstraction.
This patch fixes the error everywhere it occurs in the gdb sources.
Tested by rebuilding.
2014-06-13 Tom Tromey <tromey@redhat.com>
* cp-support.c (maint_cplus_command): Pass all_commands, not -1,
to help_list.
* guile/guile.c (info_guile_command): Pass all_commands, not -1,
to help_list.
* tui/tui-win.c (tui_command): Pass all_commands, not -1, to
help_list.
* tui/tui-regs.c (tui_reg_command): Pass all_commands, not -1, to
help_list.Pass all_commands, not -1, to help_list.
* cli/cli-dump.c (dump_command, append_command)
(srec_dump_command, ihex_dump_command, tekhex_dump_command)
(binary_dump_command, binary_append_command): Pass all_commands,
not -1, to help_list.
* cli/cli-cmds.c (info_command, set_debug): Pass all_commands, not
-1, to help_list.
* valprint.c (set_print, set_print_raw): Pass all_commands, not
-1, to help_list.
* typeprint.c (set_print_type): Pass all_commands, not -1, to
help_list.
* top.c (set_history): Pass all_commands, not -1, to help_list.
* target-descriptions.c (set_tdesc_cmd, unset_tdesc_cmd): Pass
all_commands, not -1, to help_list.
* symfile.c (overlay_command): Pass all_commands, not -1, to
help_list.
* spu-tdep.c (info_spu_command): Pass all_commands, not -1, to
help_list.
* serial.c (serial_set_cmd): Pass all_commands, not -1, to
help_list.
* ser-tcp.c (set_tcp_cmd, show_tcp_cmd): Pass all_commands, not
-1, to help_list.
* remote.c (remote_command, set_remote_cmd): Pass all_commands,
not -1, to help_list.
* ravenscar-thread.c (set_ravenscar_command): Pass all_commands,
not -1, to help_list.
* maint.c (maintenance_command, maintenance_info_command)
(maintenance_print_command, maintenance_set_cmd): Pass
all_commands, not -1, to help_list.
* macrocmd.c (macro_command): Pass all_commands, not -1, to
help_list.
* language.c (set_check): Pass all_commands, not -1, to help_list.
* infcmd.c (unset_command): Pass all_commands, not -1, to
help_list.
* frame.c (set_backtrace_cmd): Pass all_commands, not -1, to
help_list.
* dwarf2read.c (set_dwarf2_cmd): Pass all_commands, not -1, to
help_list.
* dcache.c (set_dcache_command): Pass all_commands, not -1, to
help_list.
* breakpoint.c (save_command): Pass all_commands, not -1, to
help_list.
* ada-lang.c (maint_set_ada_cmd, set_ada_command): Pass
all_commands, not -1, to help_list.
Pedro Alves
Joel Brobecker
Sandra Loosemore
Simon Marchi
Patrick Palka
Andrew Burgess
H.J. Lu
Tom Tromey
Doug Evans
Gary Benson
Eli Zaretskii