binutils-gdb/gdb/cli/cli-logging.c
Pedro Alves 616268b639 Move "tee" building down to interpreter::set_logging_proc
This patch gets rid of this hack in mi_set_logging:

      /* The tee created already is based on gdb_stdout, which for MI
	 is a console and so we end up in an infinite loop of console
	 writing to ui_file writing to console etc.  So discard the
	 existing tee (it hasn't been used yet, and MI won't ever use
	 it), and create one based on raw_stdout instead.  */

By pushing down responsibility for the tee creation to the
interpreter.  I.e., pushing the CLI bits out of handle_redirections
down to the CLI interpreter's set_logging_proc method.

This fixes a few leaks that I spotted, and then confirmed with
"valgrind --leak-check=full":

[...]
  ==21429== 56 (32 direct, 24 indirect) bytes in 1 blocks are definitely lost in loss record 30,243 of 34,980
  ==21429==    at 0x4C29216: operator new(unsigned long) (vg_replace_malloc.c:334)
  ==21429==    by 0x62D9A9: mi_set_logging(interp*, int, ui_file*, ui_file*) (mi-interp.c:1395)
  ==21429==    by 0x810B8A: current_interp_set_logging(int, ui_file*, ui_file*) (interps.c:360)
  ==21429==    by 0x61C537: handle_redirections(int) (cli-logging.c:162)
  ==21429==    by 0x61C6EC: set_logging_on(char*, int) (cli-logging.c:190)
  ==21429==    by 0x6163BE: do_cfunc(cmd_list_element*, char*, int) (cli-decode.c:105)
  ==21429==    by 0x6193C1: cmd_func(cmd_list_element*, char*, int) (cli-decode.c:1913)
  ==21429==    by 0x8DB790: execute_command(char*, int) (top.c:674)
  ==21429==    by 0x632AE6: mi_execute_cli_command(char const*, int, char const*) (mi-main.c:2343)
  ==21429==    by 0x6329BA: mi_cmd_execute(mi_parse*) (mi-main.c:2306)
  ==21429==    by 0x631E19: captured_mi_execute_command(ui_out*, mi_parse*) (mi-main.c:1998)
  ==21429==    by 0x632389: mi_execute_command(char const*, int) (mi-main.c:2163)
  ==21429==
[...]
  ==26635== 24 bytes in 1 blocks are definitely lost in loss record 20,740 of 34,995
  ==26635==    at 0x4C29216: operator new(unsigned long) (vg_replace_malloc.c:334)
  ==26635==    by 0x61C355: handle_redirections(int) (cli-logging.c:131)
  ==26635==    by 0x61C6EC: set_logging_on(char*, int) (cli-logging.c:190)
  ==26635==    by 0x6163BE: do_cfunc(cmd_list_element*, char*, int) (cli-decode.c:105)
  ==26635==    by 0x6193C1: cmd_func(cmd_list_element*, char*, int) (cli-decode.c:1913)
  ==26635==    by 0x8DB7BC: execute_command(char*, int) (top.c:674)
  ==26635==    by 0x7B9132: command_handler(char*) (event-top.c:590)
  ==26635==    by 0x7B94F7: command_line_handler(char*) (event-top.c:780)
  ==26635==    by 0x7B8ABB: gdb_rl_callback_handler(char*) (event-top.c:213)
  ==26635==    by 0x933CE9: rl_callback_read_char (callback.c:220)
  ==26635==    by 0x7B89ED: gdb_rl_callback_read_char_wrapper_noexcept() (event-top.c:175)
  ==26635==    by 0x7B8A49: gdb_rl_callback_read_char_wrapper(void*) (event-top.c:192)

One is fixed by transfering ownership of the log file to the tee.  In
pseudo-patch, since the code was moved at the same time:

 -     out = new tee_file (curr_output, false, logfile.get (), false);
 +     out = new tee_file (curr_output, false, logfile.get (), true);

The other is this bit in mi_set_logging:

    else
      {
 +      delete mi->raw_stdout;

I tried to split the leak fixes to a smaller preparatory patch, but
that was difficult exactly because of the tee hack in
handle_redirections -> mi_set_logging.

gdb/ChangeLog:
2017-02-02  Pedro Alves  <palves@redhat.com>

	* cli/cli-interp.c (struct saved_output_files, saved_output):
	Moved from cli/cli-logging.c.
	(cli_set_logging): New function.
	(cli_interp_procs): Install cli_set_logging.
	* cli/cli-interp.h (make_logging_output, cli_set_logging):
	Declare.
	* cli/cli-logging.c (struct saved_output_files, saved_output):
	Moved to cli/cli-interp.c.
	(pop_output_files): Don't save outputs here.
	(make_logging_output): New function.
	(handle_redirections): Don't build tee nor save previous outputs
	here.
	* interps.c (current_interp_set_logging): Change prototype.
	Assume there's always a set_logging_proc method installed.
	* interps.h (interp_set_logging_ftype): Change prototype.
	(current_interp_set_logging): Change prototype and adjust comment.
	* mi/mi-interp.c (mi_set_logging): Change protototype.  Adjust to
	use make_logging_output.
	* tui/tui-interp.c (tui_interp_procs): Install cli_set_logging.
2017-02-02 22:00:43 +00:00

249 lines
7.4 KiB
C

/* Command-line output logging for GDB, the GNU debugger.
Copyright (C) 2003-2017 Free Software Foundation, Inc.
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 "gdbcmd.h"
#include "ui-out.h"
#include "interps.h"
static char *saved_filename;
static char *logging_filename;
static void
show_logging_filename (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("The current logfile is \"%s\".\n"),
value);
}
static int logging_overwrite;
static void
maybe_warn_already_logging ()
{
if (saved_filename)
warning (_("Currently logging to %s. Turn the logging off and on to "
"make the new setting effective."), saved_filename);
}
static void
set_logging_overwrite (char *args, int from_tty, struct cmd_list_element *c)
{
maybe_warn_already_logging ();
}
static void
show_logging_overwrite (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file,
_("Whether logging overwrites or "
"appends to the log file is %s.\n"),
value);
}
/* Value as configured by the user. */
static int logging_redirect;
static void
set_logging_redirect (char *args, int from_tty, struct cmd_list_element *c)
{
maybe_warn_already_logging ();
}
static void
show_logging_redirect (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("The logging output mode is %s.\n"), value);
}
/* If we've pushed output files, close them and pop them. */
static void
pop_output_files (void)
{
current_interp_set_logging (NULL, false);
/* Stay consistent with handle_redirections. */
if (!current_uiout->is_mi_like_p ())
current_uiout->redirect (NULL);
}
/* See cli-interp.h. */
ui_file *
make_logging_output (ui_file *curr_output, ui_file_up logfile,
bool logging_redirect)
{
if (logging_redirect)
return logfile.release ();
else
{
/* Note that the "tee" takes ownership of the log file. */
ui_file *out = new tee_file (curr_output, false,
logfile.get (), true);
logfile.release ();
return out;
}
}
/* This is a helper for the `set logging' command. */
static void
handle_redirections (int from_tty)
{
if (saved_filename != NULL)
{
fprintf_unfiltered (gdb_stdout, "Already logging to %s.\n",
saved_filename);
return;
}
stdio_file_up log (new stdio_file ());
if (!log->open (logging_filename, logging_overwrite ? "w" : "a"))
perror_with_name (_("set logging"));
/* Redirects everything to gdb_stdout while this is running. */
if (from_tty)
{
if (!logging_redirect)
fprintf_unfiltered (gdb_stdout, "Copying output to %s.\n",
logging_filename);
else
fprintf_unfiltered (gdb_stdout, "Redirecting output to %s.\n",
logging_filename);
}
saved_filename = xstrdup (logging_filename);
/* Let the interpreter do anything it needs. */
current_interp_set_logging (std::move (log), logging_redirect);
/* Redirect the current ui-out object's output to the log. Use
gdb_stdout, not log, since the interpreter may have created a tee
that wraps the log. Don't do the redirect for MI, it confuses
MI's ui-out scheme. Note that we may get here with MI as current
interpreter, but with the current ui_out as a CLI ui_out, with
'-interpreter-exec console "set logging on"'. */
if (!current_uiout->is_mi_like_p ())
current_uiout->redirect (gdb_stdout);
}
static void
set_logging_on (char *args, int from_tty)
{
char *rest = args;
if (rest && *rest)
{
xfree (logging_filename);
logging_filename = xstrdup (rest);
}
handle_redirections (from_tty);
}
static void
set_logging_off (char *args, int from_tty)
{
if (saved_filename == NULL)
return;
pop_output_files ();
if (from_tty)
fprintf_unfiltered (gdb_stdout, "Done logging to %s.\n", saved_filename);
xfree (saved_filename);
saved_filename = NULL;
}
static void
set_logging_command (char *args, int from_tty)
{
printf_unfiltered (_("\"set logging\" lets you log output to a file.\n"
"Usage: set logging on [FILENAME]\n"
" set logging off\n"
" set logging file FILENAME\n"
" set logging overwrite [on|off]\n"
" set logging redirect [on|off]\n"));
}
static void
show_logging_command (char *args, int from_tty)
{
if (saved_filename)
printf_unfiltered (_("Currently logging to \"%s\".\n"), saved_filename);
if (saved_filename == NULL
|| strcmp (logging_filename, saved_filename) != 0)
printf_unfiltered (_("Future logs will be written to %s.\n"),
logging_filename);
if (logging_overwrite)
printf_unfiltered (_("Logs will overwrite the log file.\n"));
else
printf_unfiltered (_("Logs will be appended to the log file.\n"));
if (logging_redirect)
printf_unfiltered (_("Output will be sent only to the log file.\n"));
else
printf_unfiltered (_("Output will be logged and displayed.\n"));
}
/* Provide a prototype to silence -Wmissing-prototypes. */
extern initialize_file_ftype _initialize_cli_logging;
void
_initialize_cli_logging (void)
{
static struct cmd_list_element *set_logging_cmdlist, *show_logging_cmdlist;
add_prefix_cmd ("logging", class_support, set_logging_command,
_("Set logging options"), &set_logging_cmdlist,
"set logging ", 0, &setlist);
add_prefix_cmd ("logging", class_support, show_logging_command,
_("Show logging options"), &show_logging_cmdlist,
"show logging ", 0, &showlist);
add_setshow_boolean_cmd ("overwrite", class_support, &logging_overwrite, _("\
Set whether logging overwrites or appends to the log file."), _("\
Show whether logging overwrites or appends to the log file."), _("\
If set, logging overrides the log file."),
set_logging_overwrite,
show_logging_overwrite,
&set_logging_cmdlist, &show_logging_cmdlist);
add_setshow_boolean_cmd ("redirect", class_support, &logging_redirect, _("\
Set the logging output mode."), _("\
Show the logging output mode."), _("\
If redirect is off, output will go to both the screen and the log file.\n\
If redirect is on, output will go only to the log file."),
set_logging_redirect,
show_logging_redirect,
&set_logging_cmdlist, &show_logging_cmdlist);
add_setshow_filename_cmd ("file", class_support, &logging_filename, _("\
Set the current logfile."), _("\
Show the current logfile."), _("\
The logfile is used when directing GDB's output."),
NULL,
show_logging_filename,
&set_logging_cmdlist, &show_logging_cmdlist);
add_cmd ("on", class_support, set_logging_on,
_("Enable logging."), &set_logging_cmdlist);
add_cmd ("off", class_support, set_logging_off,
_("Disable logging."), &set_logging_cmdlist);
logging_filename = xstrdup ("gdb.txt");
}