492d29ea1c
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.
1112 lines
33 KiB
C
1112 lines
33 KiB
C
/* Top level stuff for GDB, the GNU debugger.
|
||
|
||
Copyright (C) 1999-2015 Free Software Foundation, Inc.
|
||
|
||
Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
#include "defs.h"
|
||
#include "top.h"
|
||
#include "inferior.h"
|
||
#include "infrun.h"
|
||
#include "target.h"
|
||
#include "terminal.h" /* for job_control */
|
||
#include "event-loop.h"
|
||
#include "event-top.h"
|
||
#include "interps.h"
|
||
#include <signal.h>
|
||
#include "cli/cli-script.h" /* for reset_command_nest_depth */
|
||
#include "main.h"
|
||
#include "gdbthread.h"
|
||
#include "observer.h"
|
||
#include "continuations.h"
|
||
#include "gdbcmd.h" /* for dont_repeat() */
|
||
#include "annotate.h"
|
||
#include "maint.h"
|
||
|
||
/* readline include files. */
|
||
#include "readline/readline.h"
|
||
#include "readline/history.h"
|
||
|
||
/* readline defines this. */
|
||
#undef savestring
|
||
|
||
static void rl_callback_read_char_wrapper (gdb_client_data client_data);
|
||
static void command_line_handler (char *rl);
|
||
static void change_line_handler (void);
|
||
static void command_handler (char *command);
|
||
static char *top_level_prompt (void);
|
||
|
||
/* Signal handlers. */
|
||
#ifdef SIGQUIT
|
||
static void handle_sigquit (int sig);
|
||
#endif
|
||
#ifdef SIGHUP
|
||
static void handle_sighup (int sig);
|
||
#endif
|
||
static void handle_sigfpe (int sig);
|
||
|
||
/* Functions to be invoked by the event loop in response to
|
||
signals. */
|
||
#if defined (SIGQUIT) || defined (SIGHUP)
|
||
static void async_do_nothing (gdb_client_data);
|
||
#endif
|
||
#ifdef SIGHUP
|
||
static void async_disconnect (gdb_client_data);
|
||
#endif
|
||
static void async_float_handler (gdb_client_data);
|
||
#ifdef STOP_SIGNAL
|
||
static void async_stop_sig (gdb_client_data);
|
||
#endif
|
||
static void async_sigterm_handler (gdb_client_data arg);
|
||
|
||
/* Readline offers an alternate interface, via callback
|
||
functions. These are all included in the file callback.c in the
|
||
readline distribution. This file provides (mainly) a function, which
|
||
the event loop uses as callback (i.e. event handler) whenever an event
|
||
is detected on the standard input file descriptor.
|
||
readline_callback_read_char is called (by the GDB event loop) whenever
|
||
there is a new character ready on the input stream. This function
|
||
incrementally builds a buffer internal to readline where it
|
||
accumulates the line read up to the point of invocation. In the
|
||
special case in which the character read is newline, the function
|
||
invokes a GDB supplied callback routine, which does the processing of
|
||
a full command line. This latter routine is the asynchronous analog
|
||
of the old command_line_input in gdb. Instead of invoking (and waiting
|
||
for) readline to read the command line and pass it back to
|
||
command_loop for processing, the new command_line_handler function has
|
||
the command line already available as its parameter. INPUT_HANDLER is
|
||
to be set to the function that readline will invoke when a complete
|
||
line of input is ready. CALL_READLINE is to be set to the function
|
||
that readline offers as callback to the event_loop. */
|
||
|
||
void (*input_handler) (char *);
|
||
void (*call_readline) (gdb_client_data);
|
||
|
||
/* Important variables for the event loop. */
|
||
|
||
/* This is used to determine if GDB is using the readline library or
|
||
its own simplified form of readline. It is used by the asynchronous
|
||
form of the set editing command.
|
||
ezannoni: as of 1999-04-29 I expect that this
|
||
variable will not be used after gdb is changed to use the event
|
||
loop as default engine, and event-top.c is merged into top.c. */
|
||
int async_command_editing_p;
|
||
|
||
/* This is the annotation suffix that will be used when the
|
||
annotation_level is 2. */
|
||
char *async_annotation_suffix;
|
||
|
||
/* This is used to display the notification of the completion of an
|
||
asynchronous execution command. */
|
||
int exec_done_display_p = 0;
|
||
|
||
/* This is the file descriptor for the input stream that GDB uses to
|
||
read commands from. */
|
||
int input_fd;
|
||
|
||
/* Used by the stdin event handler to compensate for missed stdin events.
|
||
Setting this to a non-zero value inside an stdin callback makes the callback
|
||
run again. */
|
||
int call_stdin_event_handler_again_p;
|
||
|
||
/* Signal handling variables. */
|
||
/* Each of these is a pointer to a function that the event loop will
|
||
invoke if the corresponding signal has received. The real signal
|
||
handlers mark these functions as ready to be executed and the event
|
||
loop, in a later iteration, calls them. See the function
|
||
invoke_async_signal_handler. */
|
||
static struct async_signal_handler *sigint_token;
|
||
#ifdef SIGHUP
|
||
static struct async_signal_handler *sighup_token;
|
||
#endif
|
||
#ifdef SIGQUIT
|
||
static struct async_signal_handler *sigquit_token;
|
||
#endif
|
||
static struct async_signal_handler *sigfpe_token;
|
||
#ifdef STOP_SIGNAL
|
||
static struct async_signal_handler *sigtstp_token;
|
||
#endif
|
||
static struct async_signal_handler *async_sigterm_token;
|
||
|
||
/* Structure to save a partially entered command. This is used when
|
||
the user types '\' at the end of a command line. This is necessary
|
||
because each line of input is handled by a different call to
|
||
command_line_handler, and normally there is no state retained
|
||
between different calls. */
|
||
static int more_to_come = 0;
|
||
|
||
struct readline_input_state
|
||
{
|
||
char *linebuffer;
|
||
char *linebuffer_ptr;
|
||
}
|
||
readline_input_state;
|
||
|
||
/* This hook is called by rl_callback_read_char_wrapper after each
|
||
character is processed. */
|
||
void (*after_char_processing_hook) (void);
|
||
|
||
|
||
/* Wrapper function for calling into the readline library. The event
|
||
loop expects the callback function to have a paramter, while
|
||
readline expects none. */
|
||
static void
|
||
rl_callback_read_char_wrapper (gdb_client_data client_data)
|
||
{
|
||
rl_callback_read_char ();
|
||
if (after_char_processing_hook)
|
||
(*after_char_processing_hook) ();
|
||
}
|
||
|
||
/* Initialize all the necessary variables, start the event loop,
|
||
register readline, and stdin, start the loop. The DATA is the
|
||
interpreter data cookie, ignored for now. */
|
||
|
||
void
|
||
cli_command_loop (void *data)
|
||
{
|
||
display_gdb_prompt (0);
|
||
|
||
/* Now it's time to start the event loop. */
|
||
start_event_loop ();
|
||
}
|
||
|
||
/* Change the function to be invoked every time there is a character
|
||
ready on stdin. This is used when the user sets the editing off,
|
||
therefore bypassing readline, and letting gdb handle the input
|
||
itself, via gdb_readline2. Also it is used in the opposite case in
|
||
which the user sets editing on again, by restoring readline
|
||
handling of the input. */
|
||
static void
|
||
change_line_handler (void)
|
||
{
|
||
/* NOTE: this operates on input_fd, not instream. If we are reading
|
||
commands from a file, instream will point to the file. However in
|
||
async mode, we always read commands from a file with editing
|
||
off. This means that the 'set editing on/off' will have effect
|
||
only on the interactive session. */
|
||
|
||
if (async_command_editing_p)
|
||
{
|
||
/* Turn on editing by using readline. */
|
||
call_readline = rl_callback_read_char_wrapper;
|
||
input_handler = command_line_handler;
|
||
}
|
||
else
|
||
{
|
||
/* Turn off editing by using gdb_readline2. */
|
||
gdb_rl_callback_handler_remove ();
|
||
call_readline = gdb_readline2;
|
||
|
||
/* Set up the command handler as well, in case we are called as
|
||
first thing from .gdbinit. */
|
||
input_handler = command_line_handler;
|
||
}
|
||
}
|
||
|
||
/* The functions below are wrappers for rl_callback_handler_remove and
|
||
rl_callback_handler_install that keep track of whether the callback
|
||
handler is installed in readline. This is necessary because after
|
||
handling a target event of a background execution command, we may
|
||
need to reinstall the callback handler if it was removed due to a
|
||
secondary prompt. See gdb_readline_wrapper_line. We don't
|
||
unconditionally install the handler for every target event because
|
||
that also clears the line buffer, thus installing it while the user
|
||
is typing would lose input. */
|
||
|
||
/* Whether we've registered a callback handler with readline. */
|
||
static int callback_handler_installed;
|
||
|
||
/* See event-top.h, and above. */
|
||
|
||
void
|
||
gdb_rl_callback_handler_remove (void)
|
||
{
|
||
rl_callback_handler_remove ();
|
||
callback_handler_installed = 0;
|
||
}
|
||
|
||
/* See event-top.h, and above. Note this wrapper doesn't have an
|
||
actual callback parameter because we always install
|
||
INPUT_HANDLER. */
|
||
|
||
void
|
||
gdb_rl_callback_handler_install (const char *prompt)
|
||
{
|
||
/* Calling rl_callback_handler_install resets readline's input
|
||
buffer. Calling this when we were already processing input
|
||
therefore loses input. */
|
||
gdb_assert (!callback_handler_installed);
|
||
|
||
rl_callback_handler_install (prompt, input_handler);
|
||
callback_handler_installed = 1;
|
||
}
|
||
|
||
/* See event-top.h, and above. */
|
||
|
||
void
|
||
gdb_rl_callback_handler_reinstall (void)
|
||
{
|
||
if (!callback_handler_installed)
|
||
{
|
||
/* Passing NULL as prompt argument tells readline to not display
|
||
a prompt. */
|
||
gdb_rl_callback_handler_install (NULL);
|
||
}
|
||
}
|
||
|
||
/* Displays the prompt. If the argument NEW_PROMPT is NULL, the
|
||
prompt that is displayed is the current top level prompt.
|
||
Otherwise, it displays whatever NEW_PROMPT is as a local/secondary
|
||
prompt.
|
||
|
||
This is used after each gdb command has completed, and in the
|
||
following cases:
|
||
|
||
1. When the user enters a command line which is ended by '\'
|
||
indicating that the command will continue on the next line. In
|
||
that case the prompt that is displayed is the empty string.
|
||
|
||
2. When the user is entering 'commands' for a breakpoint, or
|
||
actions for a tracepoint. In this case the prompt will be '>'
|
||
|
||
3. On prompting for pagination. */
|
||
|
||
void
|
||
display_gdb_prompt (const char *new_prompt)
|
||
{
|
||
char *actual_gdb_prompt = NULL;
|
||
struct cleanup *old_chain;
|
||
|
||
annotate_display_prompt ();
|
||
|
||
/* Reset the nesting depth used when trace-commands is set. */
|
||
reset_command_nest_depth ();
|
||
|
||
old_chain = make_cleanup (free_current_contents, &actual_gdb_prompt);
|
||
|
||
/* Do not call the python hook on an explicit prompt change as
|
||
passed to this function, as this forms a secondary/local prompt,
|
||
IE, displayed but not set. */
|
||
if (! new_prompt)
|
||
{
|
||
if (sync_execution)
|
||
{
|
||
/* This is to trick readline into not trying to display the
|
||
prompt. Even though we display the prompt using this
|
||
function, readline still tries to do its own display if
|
||
we don't call rl_callback_handler_install and
|
||
rl_callback_handler_remove (which readline detects
|
||
because a global variable is not set). If readline did
|
||
that, it could mess up gdb signal handlers for SIGINT.
|
||
Readline assumes that between calls to rl_set_signals and
|
||
rl_clear_signals gdb doesn't do anything with the signal
|
||
handlers. Well, that's not the case, because when the
|
||
target executes we change the SIGINT signal handler. If
|
||
we allowed readline to display the prompt, the signal
|
||
handler change would happen exactly between the calls to
|
||
the above two functions. Calling
|
||
rl_callback_handler_remove(), does the job. */
|
||
|
||
gdb_rl_callback_handler_remove ();
|
||
do_cleanups (old_chain);
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* Display the top level prompt. */
|
||
actual_gdb_prompt = top_level_prompt ();
|
||
}
|
||
}
|
||
else
|
||
actual_gdb_prompt = xstrdup (new_prompt);
|
||
|
||
if (async_command_editing_p)
|
||
{
|
||
gdb_rl_callback_handler_remove ();
|
||
gdb_rl_callback_handler_install (actual_gdb_prompt);
|
||
}
|
||
/* new_prompt at this point can be the top of the stack or the one
|
||
passed in. It can't be NULL. */
|
||
else
|
||
{
|
||
/* Don't use a _filtered function here. It causes the assumed
|
||
character position to be off, since the newline we read from
|
||
the user is not accounted for. */
|
||
fputs_unfiltered (actual_gdb_prompt, gdb_stdout);
|
||
gdb_flush (gdb_stdout);
|
||
}
|
||
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
/* Return the top level prompt, as specified by "set prompt", possibly
|
||
overriden by the python gdb.prompt_hook hook, and then composed
|
||
with the prompt prefix and suffix (annotations). The caller is
|
||
responsible for freeing the returned string. */
|
||
|
||
static char *
|
||
top_level_prompt (void)
|
||
{
|
||
char *prefix;
|
||
char *prompt = NULL;
|
||
char *suffix;
|
||
char *composed_prompt;
|
||
size_t prompt_length;
|
||
|
||
/* Give observers a chance of changing the prompt. E.g., the python
|
||
`gdb.prompt_hook' is installed as an observer. */
|
||
observer_notify_before_prompt (get_prompt ());
|
||
|
||
prompt = xstrdup (get_prompt ());
|
||
|
||
if (annotation_level >= 2)
|
||
{
|
||
/* Prefix needs to have new line at end. */
|
||
prefix = (char *) alloca (strlen (async_annotation_suffix) + 10);
|
||
strcpy (prefix, "\n\032\032pre-");
|
||
strcat (prefix, async_annotation_suffix);
|
||
strcat (prefix, "\n");
|
||
|
||
/* Suffix needs to have a new line at end and \032 \032 at
|
||
beginning. */
|
||
suffix = (char *) alloca (strlen (async_annotation_suffix) + 6);
|
||
strcpy (suffix, "\n\032\032");
|
||
strcat (suffix, async_annotation_suffix);
|
||
strcat (suffix, "\n");
|
||
}
|
||
else
|
||
{
|
||
prefix = "";
|
||
suffix = "";
|
||
}
|
||
|
||
prompt_length = strlen (prefix) + strlen (prompt) + strlen (suffix);
|
||
composed_prompt = xmalloc (prompt_length + 1);
|
||
|
||
strcpy (composed_prompt, prefix);
|
||
strcat (composed_prompt, prompt);
|
||
strcat (composed_prompt, suffix);
|
||
|
||
xfree (prompt);
|
||
|
||
return composed_prompt;
|
||
}
|
||
|
||
/* When there is an event ready on the stdin file desriptor, instead
|
||
of calling readline directly throught the callback function, or
|
||
instead of calling gdb_readline2, give gdb a chance to detect
|
||
errors and do something. */
|
||
void
|
||
stdin_event_handler (int error, gdb_client_data client_data)
|
||
{
|
||
if (error)
|
||
{
|
||
printf_unfiltered (_("error detected on stdin\n"));
|
||
delete_file_handler (input_fd);
|
||
discard_all_continuations ();
|
||
discard_all_intermediate_continuations ();
|
||
/* If stdin died, we may as well kill gdb. */
|
||
quit_command ((char *) 0, stdin == instream);
|
||
}
|
||
else
|
||
{
|
||
do
|
||
{
|
||
call_stdin_event_handler_again_p = 0;
|
||
(*call_readline) (client_data);
|
||
} while (call_stdin_event_handler_again_p != 0);
|
||
}
|
||
}
|
||
|
||
/* Re-enable stdin after the end of an execution command in
|
||
synchronous mode, or after an error from the target, and we aborted
|
||
the exec operation. */
|
||
|
||
void
|
||
async_enable_stdin (void)
|
||
{
|
||
if (sync_execution)
|
||
{
|
||
/* See NOTE in async_disable_stdin(). */
|
||
/* FIXME: cagney/1999-09-27: Call this before clearing
|
||
sync_execution. Current target_terminal_ours() implementations
|
||
check for sync_execution before switching the terminal. */
|
||
target_terminal_ours ();
|
||
sync_execution = 0;
|
||
}
|
||
}
|
||
|
||
/* Disable reads from stdin (the console) marking the command as
|
||
synchronous. */
|
||
|
||
void
|
||
async_disable_stdin (void)
|
||
{
|
||
sync_execution = 1;
|
||
}
|
||
|
||
|
||
/* Handles a gdb command. This function is called by
|
||
command_line_handler, which has processed one or more input lines
|
||
into COMMAND. */
|
||
/* NOTE: 1999-04-30 This is the asynchronous version of the command_loop
|
||
function. The command_loop function will be obsolete when we
|
||
switch to use the event loop at every execution of gdb. */
|
||
static void
|
||
command_handler (char *command)
|
||
{
|
||
int stdin_is_tty = ISATTY (stdin);
|
||
struct cleanup *stat_chain;
|
||
|
||
clear_quit_flag ();
|
||
if (instream == stdin && stdin_is_tty)
|
||
reinitialize_more_filter ();
|
||
|
||
/* If readline returned a NULL command, it means that the connection
|
||
with the terminal is gone. This happens at the end of a
|
||
testsuite run, after Expect has hung up but GDB is still alive.
|
||
In such a case, we just quit gdb killing the inferior program
|
||
too. */
|
||
if (command == 0)
|
||
{
|
||
printf_unfiltered ("quit\n");
|
||
execute_command ("quit", stdin == instream);
|
||
}
|
||
|
||
stat_chain = make_command_stats_cleanup (1);
|
||
|
||
execute_command (command, instream == stdin);
|
||
|
||
/* Do any commands attached to breakpoint we stopped at. */
|
||
bpstat_do_actions ();
|
||
|
||
do_cleanups (stat_chain);
|
||
}
|
||
|
||
/* Handle a complete line of input. This is called by the callback
|
||
mechanism within the readline library. Deal with incomplete
|
||
commands as well, by saving the partial input in a global
|
||
buffer. */
|
||
|
||
/* NOTE: 1999-04-30 This is the asynchronous version of the
|
||
command_line_input function; command_line_input will become
|
||
obsolete once we use the event loop as the default mechanism in
|
||
GDB. */
|
||
static void
|
||
command_line_handler (char *rl)
|
||
{
|
||
static char *linebuffer = 0;
|
||
static unsigned linelength = 0;
|
||
char *p;
|
||
char *p1;
|
||
char *nline;
|
||
int repeat = (instream == stdin);
|
||
|
||
if (annotation_level > 1 && instream == stdin)
|
||
{
|
||
printf_unfiltered (("\n\032\032post-"));
|
||
puts_unfiltered (async_annotation_suffix);
|
||
printf_unfiltered (("\n"));
|
||
}
|
||
|
||
if (linebuffer == 0)
|
||
{
|
||
linelength = 80;
|
||
linebuffer = (char *) xmalloc (linelength);
|
||
linebuffer[0] = '\0';
|
||
}
|
||
|
||
p = linebuffer;
|
||
|
||
if (more_to_come)
|
||
{
|
||
strcpy (linebuffer, readline_input_state.linebuffer);
|
||
p = readline_input_state.linebuffer_ptr;
|
||
xfree (readline_input_state.linebuffer);
|
||
more_to_come = 0;
|
||
}
|
||
|
||
#ifdef STOP_SIGNAL
|
||
if (job_control)
|
||
signal (STOP_SIGNAL, handle_stop_sig);
|
||
#endif
|
||
|
||
/* Make sure that all output has been output. Some machines may let
|
||
you get away with leaving out some of the gdb_flush, but not
|
||
all. */
|
||
wrap_here ("");
|
||
gdb_flush (gdb_stdout);
|
||
gdb_flush (gdb_stderr);
|
||
|
||
if (source_file_name != NULL)
|
||
++source_line_number;
|
||
|
||
/* If we are in this case, then command_handler will call quit
|
||
and exit from gdb. */
|
||
if (!rl || rl == (char *) EOF)
|
||
{
|
||
command_handler (0);
|
||
return; /* Lint. */
|
||
}
|
||
if (strlen (rl) + 1 + (p - linebuffer) > linelength)
|
||
{
|
||
linelength = strlen (rl) + 1 + (p - linebuffer);
|
||
nline = (char *) xrealloc (linebuffer, linelength);
|
||
p += nline - linebuffer;
|
||
linebuffer = nline;
|
||
}
|
||
p1 = rl;
|
||
/* Copy line. Don't copy null at end. (Leaves line alone
|
||
if this was just a newline). */
|
||
while (*p1)
|
||
*p++ = *p1++;
|
||
|
||
xfree (rl); /* Allocated in readline. */
|
||
|
||
if (p > linebuffer && *(p - 1) == '\\')
|
||
{
|
||
*p = '\0';
|
||
p--; /* Put on top of '\'. */
|
||
|
||
readline_input_state.linebuffer = xstrdup (linebuffer);
|
||
readline_input_state.linebuffer_ptr = p;
|
||
|
||
/* We will not invoke a execute_command if there is more
|
||
input expected to complete the command. So, we need to
|
||
print an empty prompt here. */
|
||
more_to_come = 1;
|
||
display_gdb_prompt ("");
|
||
return;
|
||
}
|
||
|
||
#ifdef STOP_SIGNAL
|
||
if (job_control)
|
||
signal (STOP_SIGNAL, SIG_DFL);
|
||
#endif
|
||
|
||
#define SERVER_COMMAND_LENGTH 7
|
||
server_command =
|
||
(p - linebuffer > SERVER_COMMAND_LENGTH)
|
||
&& strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0;
|
||
if (server_command)
|
||
{
|
||
/* Note that we don't set `line'. Between this and the check in
|
||
dont_repeat, this insures that repeating will still do the
|
||
right thing. */
|
||
*p = '\0';
|
||
command_handler (linebuffer + SERVER_COMMAND_LENGTH);
|
||
display_gdb_prompt (0);
|
||
return;
|
||
}
|
||
|
||
/* Do history expansion if that is wished. */
|
||
if (history_expansion_p && instream == stdin
|
||
&& ISATTY (instream))
|
||
{
|
||
char *history_value;
|
||
int expanded;
|
||
|
||
*p = '\0'; /* Insert null now. */
|
||
expanded = history_expand (linebuffer, &history_value);
|
||
if (expanded)
|
||
{
|
||
/* Print the changes. */
|
||
printf_unfiltered ("%s\n", history_value);
|
||
|
||
/* If there was an error, call this function again. */
|
||
if (expanded < 0)
|
||
{
|
||
xfree (history_value);
|
||
return;
|
||
}
|
||
if (strlen (history_value) > linelength)
|
||
{
|
||
linelength = strlen (history_value) + 1;
|
||
linebuffer = (char *) xrealloc (linebuffer, linelength);
|
||
}
|
||
strcpy (linebuffer, history_value);
|
||
p = linebuffer + strlen (linebuffer);
|
||
}
|
||
xfree (history_value);
|
||
}
|
||
|
||
/* If we just got an empty line, and that is supposed to repeat the
|
||
previous command, return the value in the global buffer. */
|
||
if (repeat && p == linebuffer && *p != '\\')
|
||
{
|
||
command_handler (saved_command_line);
|
||
display_gdb_prompt (0);
|
||
return;
|
||
}
|
||
|
||
for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++);
|
||
if (repeat && !*p1)
|
||
{
|
||
command_handler (saved_command_line);
|
||
display_gdb_prompt (0);
|
||
return;
|
||
}
|
||
|
||
*p = 0;
|
||
|
||
/* Add line to history if appropriate. */
|
||
if (*linebuffer && input_from_terminal_p ())
|
||
gdb_add_history (linebuffer);
|
||
|
||
/* Note: lines consisting solely of comments are added to the command
|
||
history. This is useful when you type a command, and then
|
||
realize you don't want to execute it quite yet. You can comment
|
||
out the command and then later fetch it from the value history
|
||
and remove the '#'. The kill ring is probably better, but some
|
||
people are in the habit of commenting things out. */
|
||
if (*p1 == '#')
|
||
*p1 = '\0'; /* Found a comment. */
|
||
|
||
/* Save into global buffer if appropriate. */
|
||
if (repeat)
|
||
{
|
||
if (linelength > saved_command_line_size)
|
||
{
|
||
saved_command_line = xrealloc (saved_command_line, linelength);
|
||
saved_command_line_size = linelength;
|
||
}
|
||
strcpy (saved_command_line, linebuffer);
|
||
if (!more_to_come)
|
||
{
|
||
command_handler (saved_command_line);
|
||
display_gdb_prompt (0);
|
||
}
|
||
return;
|
||
}
|
||
|
||
command_handler (linebuffer);
|
||
display_gdb_prompt (0);
|
||
return;
|
||
}
|
||
|
||
/* Does reading of input from terminal w/o the editing features
|
||
provided by the readline library. */
|
||
|
||
/* NOTE: 1999-04-30 Asynchronous version of gdb_readline; gdb_readline
|
||
will become obsolete when the event loop is made the default
|
||
execution for gdb. */
|
||
void
|
||
gdb_readline2 (gdb_client_data client_data)
|
||
{
|
||
int c;
|
||
char *result;
|
||
int input_index = 0;
|
||
int result_size = 80;
|
||
static int done_once = 0;
|
||
|
||
/* Unbuffer the input stream, so that, later on, the calls to fgetc
|
||
fetch only one char at the time from the stream. The fgetc's will
|
||
get up to the first newline, but there may be more chars in the
|
||
stream after '\n'. If we buffer the input and fgetc drains the
|
||
stream, getting stuff beyond the newline as well, a select, done
|
||
afterwards will not trigger. */
|
||
if (!done_once && !ISATTY (instream))
|
||
{
|
||
setbuf (instream, NULL);
|
||
done_once = 1;
|
||
}
|
||
|
||
result = (char *) xmalloc (result_size);
|
||
|
||
/* We still need the while loop here, even though it would seem
|
||
obvious to invoke gdb_readline2 at every character entered. If
|
||
not using the readline library, the terminal is in cooked mode,
|
||
which sends the characters all at once. Poll will notice that the
|
||
input fd has changed state only after enter is pressed. At this
|
||
point we still need to fetch all the chars entered. */
|
||
|
||
while (1)
|
||
{
|
||
/* Read from stdin if we are executing a user defined command.
|
||
This is the right thing for prompt_for_continue, at least. */
|
||
c = fgetc (instream ? instream : stdin);
|
||
|
||
if (c == EOF)
|
||
{
|
||
if (input_index > 0)
|
||
/* The last line does not end with a newline. Return it,
|
||
and if we are called again fgetc will still return EOF
|
||
and we'll return NULL then. */
|
||
break;
|
||
xfree (result);
|
||
(*input_handler) (0);
|
||
return;
|
||
}
|
||
|
||
if (c == '\n')
|
||
{
|
||
if (input_index > 0 && result[input_index - 1] == '\r')
|
||
input_index--;
|
||
break;
|
||
}
|
||
|
||
result[input_index++] = c;
|
||
while (input_index >= result_size)
|
||
{
|
||
result_size *= 2;
|
||
result = (char *) xrealloc (result, result_size);
|
||
}
|
||
}
|
||
|
||
result[input_index++] = '\0';
|
||
(*input_handler) (result);
|
||
}
|
||
|
||
|
||
/* Initialization of signal handlers and tokens. There is a function
|
||
handle_sig* for each of the signals GDB cares about. Specifically:
|
||
SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These
|
||
functions are the actual signal handlers associated to the signals
|
||
via calls to signal(). The only job for these functions is to
|
||
enqueue the appropriate event/procedure with the event loop. Such
|
||
procedures are the old signal handlers. The event loop will take
|
||
care of invoking the queued procedures to perform the usual tasks
|
||
associated with the reception of the signal. */
|
||
/* NOTE: 1999-04-30 This is the asynchronous version of init_signals.
|
||
init_signals will become obsolete as we move to have to event loop
|
||
as the default for gdb. */
|
||
void
|
||
async_init_signals (void)
|
||
{
|
||
signal (SIGINT, handle_sigint);
|
||
sigint_token =
|
||
create_async_signal_handler (async_request_quit, NULL);
|
||
signal (SIGTERM, handle_sigterm);
|
||
async_sigterm_token
|
||
= create_async_signal_handler (async_sigterm_handler, NULL);
|
||
|
||
/* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed
|
||
to the inferior and breakpoints will be ignored. */
|
||
#ifdef SIGTRAP
|
||
signal (SIGTRAP, SIG_DFL);
|
||
#endif
|
||
|
||
#ifdef SIGQUIT
|
||
/* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get
|
||
passed to the inferior, which we don't want. It would be
|
||
possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but
|
||
on BSD4.3 systems using vfork, that can affect the
|
||
GDB process as well as the inferior (the signal handling tables
|
||
might be in memory, shared between the two). Since we establish
|
||
a handler for SIGQUIT, when we call exec it will set the signal
|
||
to SIG_DFL for us. */
|
||
signal (SIGQUIT, handle_sigquit);
|
||
sigquit_token =
|
||
create_async_signal_handler (async_do_nothing, NULL);
|
||
#endif
|
||
#ifdef SIGHUP
|
||
if (signal (SIGHUP, handle_sighup) != SIG_IGN)
|
||
sighup_token =
|
||
create_async_signal_handler (async_disconnect, NULL);
|
||
else
|
||
sighup_token =
|
||
create_async_signal_handler (async_do_nothing, NULL);
|
||
#endif
|
||
signal (SIGFPE, handle_sigfpe);
|
||
sigfpe_token =
|
||
create_async_signal_handler (async_float_handler, NULL);
|
||
|
||
#ifdef STOP_SIGNAL
|
||
sigtstp_token =
|
||
create_async_signal_handler (async_stop_sig, NULL);
|
||
#endif
|
||
}
|
||
|
||
/* Tell the event loop what to do if SIGINT is received.
|
||
See event-signal.c. */
|
||
void
|
||
handle_sigint (int sig)
|
||
{
|
||
signal (sig, handle_sigint);
|
||
|
||
/* We could be running in a loop reading in symfiles or something so
|
||
it may be quite a while before we get back to the event loop. So
|
||
set quit_flag to 1 here. Then if QUIT is called before we get to
|
||
the event loop, we will unwind as expected. */
|
||
|
||
set_quit_flag ();
|
||
|
||
/* If immediate_quit is set, we go ahead and process the SIGINT right
|
||
away, even if we usually would defer this to the event loop. The
|
||
assumption here is that it is safe to process ^C immediately if
|
||
immediate_quit is set. If we didn't, SIGINT would be really
|
||
processed only the next time through the event loop. To get to
|
||
that point, though, the command that we want to interrupt needs to
|
||
finish first, which is unacceptable. If immediate quit is not set,
|
||
we process SIGINT the next time through the loop, which is fine. */
|
||
gdb_call_async_signal_handler (sigint_token, immediate_quit);
|
||
}
|
||
|
||
/* Handle GDB exit upon receiving SIGTERM if target_can_async_p (). */
|
||
|
||
static void
|
||
async_sigterm_handler (gdb_client_data arg)
|
||
{
|
||
quit_force (NULL, stdin == instream);
|
||
}
|
||
|
||
/* See defs.h. */
|
||
volatile int sync_quit_force_run;
|
||
|
||
/* Quit GDB if SIGTERM is received.
|
||
GDB would quit anyway, but this way it will clean up properly. */
|
||
void
|
||
handle_sigterm (int sig)
|
||
{
|
||
signal (sig, handle_sigterm);
|
||
|
||
/* Call quit_force in a signal safe way.
|
||
quit_force itself is not signal safe. */
|
||
if (target_can_async_p ())
|
||
mark_async_signal_handler (async_sigterm_token);
|
||
else
|
||
{
|
||
sync_quit_force_run = 1;
|
||
set_quit_flag ();
|
||
}
|
||
}
|
||
|
||
/* Do the quit. All the checks have been done by the caller. */
|
||
void
|
||
async_request_quit (gdb_client_data arg)
|
||
{
|
||
/* If the quit_flag has gotten reset back to 0 by the time we get
|
||
back here, that means that an exception was thrown to unwind the
|
||
current command before we got back to the event loop. So there
|
||
is no reason to call quit again here. */
|
||
|
||
if (check_quit_flag ())
|
||
quit ();
|
||
}
|
||
|
||
#ifdef SIGQUIT
|
||
/* Tell the event loop what to do if SIGQUIT is received.
|
||
See event-signal.c. */
|
||
static void
|
||
handle_sigquit (int sig)
|
||
{
|
||
mark_async_signal_handler (sigquit_token);
|
||
signal (sig, handle_sigquit);
|
||
}
|
||
#endif
|
||
|
||
#if defined (SIGQUIT) || defined (SIGHUP)
|
||
/* Called by the event loop in response to a SIGQUIT or an
|
||
ignored SIGHUP. */
|
||
static void
|
||
async_do_nothing (gdb_client_data arg)
|
||
{
|
||
/* Empty function body. */
|
||
}
|
||
#endif
|
||
|
||
#ifdef SIGHUP
|
||
/* Tell the event loop what to do if SIGHUP is received.
|
||
See event-signal.c. */
|
||
static void
|
||
handle_sighup (int sig)
|
||
{
|
||
mark_async_signal_handler (sighup_token);
|
||
signal (sig, handle_sighup);
|
||
}
|
||
|
||
/* Called by the event loop to process a SIGHUP. */
|
||
static void
|
||
async_disconnect (gdb_client_data arg)
|
||
{
|
||
|
||
TRY
|
||
{
|
||
quit_cover ();
|
||
}
|
||
|
||
CATCH (exception, RETURN_MASK_ALL)
|
||
{
|
||
fputs_filtered ("Could not kill the program being debugged",
|
||
gdb_stderr);
|
||
exception_print (gdb_stderr, exception);
|
||
}
|
||
END_CATCH
|
||
|
||
TRY
|
||
{
|
||
pop_all_targets ();
|
||
}
|
||
CATCH (exception, RETURN_MASK_ALL)
|
||
{
|
||
}
|
||
END_CATCH
|
||
|
||
signal (SIGHUP, SIG_DFL); /*FIXME: ??????????? */
|
||
raise (SIGHUP);
|
||
}
|
||
#endif
|
||
|
||
#ifdef STOP_SIGNAL
|
||
void
|
||
handle_stop_sig (int sig)
|
||
{
|
||
mark_async_signal_handler (sigtstp_token);
|
||
signal (sig, handle_stop_sig);
|
||
}
|
||
|
||
static void
|
||
async_stop_sig (gdb_client_data arg)
|
||
{
|
||
char *prompt = get_prompt ();
|
||
|
||
#if STOP_SIGNAL == SIGTSTP
|
||
signal (SIGTSTP, SIG_DFL);
|
||
#if HAVE_SIGPROCMASK
|
||
{
|
||
sigset_t zero;
|
||
|
||
sigemptyset (&zero);
|
||
sigprocmask (SIG_SETMASK, &zero, 0);
|
||
}
|
||
#elif HAVE_SIGSETMASK
|
||
sigsetmask (0);
|
||
#endif
|
||
raise (SIGTSTP);
|
||
signal (SIGTSTP, handle_stop_sig);
|
||
#else
|
||
signal (STOP_SIGNAL, handle_stop_sig);
|
||
#endif
|
||
printf_unfiltered ("%s", prompt);
|
||
gdb_flush (gdb_stdout);
|
||
|
||
/* Forget about any previous command -- null line now will do
|
||
nothing. */
|
||
dont_repeat ();
|
||
}
|
||
#endif /* STOP_SIGNAL */
|
||
|
||
/* Tell the event loop what to do if SIGFPE is received.
|
||
See event-signal.c. */
|
||
static void
|
||
handle_sigfpe (int sig)
|
||
{
|
||
mark_async_signal_handler (sigfpe_token);
|
||
signal (sig, handle_sigfpe);
|
||
}
|
||
|
||
/* Event loop will call this functin to process a SIGFPE. */
|
||
static void
|
||
async_float_handler (gdb_client_data arg)
|
||
{
|
||
/* This message is based on ANSI C, section 4.7. Note that integer
|
||
divide by zero causes this, so "float" is a misnomer. */
|
||
error (_("Erroneous arithmetic operation."));
|
||
}
|
||
|
||
|
||
/* Called by do_setshow_command. */
|
||
void
|
||
set_async_editing_command (char *args, int from_tty,
|
||
struct cmd_list_element *c)
|
||
{
|
||
change_line_handler ();
|
||
}
|
||
|
||
/* Set things up for readline to be invoked via the alternate
|
||
interface, i.e. via a callback function (rl_callback_read_char),
|
||
and hook up instream to the event loop. */
|
||
void
|
||
gdb_setup_readline (void)
|
||
{
|
||
/* This function is a noop for the sync case. The assumption is
|
||
that the sync setup is ALL done in gdb_init, and we would only
|
||
mess it up here. The sync stuff should really go away over
|
||
time. */
|
||
if (!batch_silent)
|
||
gdb_stdout = stdio_fileopen (stdout);
|
||
gdb_stderr = stderr_fileopen ();
|
||
gdb_stdlog = gdb_stderr; /* for moment */
|
||
gdb_stdtarg = gdb_stderr; /* for moment */
|
||
gdb_stdtargerr = gdb_stderr; /* for moment */
|
||
|
||
/* If the input stream is connected to a terminal, turn on
|
||
editing. */
|
||
if (ISATTY (instream))
|
||
{
|
||
/* Tell gdb that we will be using the readline library. This
|
||
could be overwritten by a command in .gdbinit like 'set
|
||
editing on' or 'off'. */
|
||
async_command_editing_p = 1;
|
||
|
||
/* When a character is detected on instream by select or poll,
|
||
readline will be invoked via this callback function. */
|
||
call_readline = rl_callback_read_char_wrapper;
|
||
}
|
||
else
|
||
{
|
||
async_command_editing_p = 0;
|
||
call_readline = gdb_readline2;
|
||
}
|
||
|
||
/* When readline has read an end-of-line character, it passes the
|
||
complete line to gdb for processing; command_line_handler is the
|
||
function that does this. */
|
||
input_handler = command_line_handler;
|
||
|
||
/* Tell readline to use the same input stream that gdb uses. */
|
||
rl_instream = instream;
|
||
|
||
/* Get a file descriptor for the input stream, so that we can
|
||
register it with the event loop. */
|
||
input_fd = fileno (instream);
|
||
|
||
/* Now we need to create the event sources for the input file
|
||
descriptor. */
|
||
/* At this point in time, this is the only event source that we
|
||
register with the even loop. Another source is going to be the
|
||
target program (inferior), but that must be registered only when
|
||
it actually exists (I.e. after we say 'run' or after we connect
|
||
to a remote target. */
|
||
add_file_handler (input_fd, stdin_event_handler, 0);
|
||
}
|
||
|
||
/* Disable command input through the standard CLI channels. Used in
|
||
the suspend proc for interpreters that use the standard gdb readline
|
||
interface, like the cli & the mi. */
|
||
void
|
||
gdb_disable_readline (void)
|
||
{
|
||
/* FIXME - It is too heavyweight to delete and remake these every
|
||
time you run an interpreter that needs readline. It is probably
|
||
better to have the interpreters cache these, which in turn means
|
||
that this needs to be moved into interpreter specific code. */
|
||
|
||
#if 0
|
||
ui_file_delete (gdb_stdout);
|
||
ui_file_delete (gdb_stderr);
|
||
gdb_stdlog = NULL;
|
||
gdb_stdtarg = NULL;
|
||
gdb_stdtargerr = NULL;
|
||
#endif
|
||
|
||
gdb_rl_callback_handler_remove ();
|
||
delete_file_handler (input_fd);
|
||
}
|