old-cross-binutils/gdb/mi/mi-cmd-catch.c
Joel Brobecker 2df4d1d5c4 Dandling memory pointers in Ada catchpoints with GDB/MI.
When using the GDB/MI commands to insert a catchpoint on a specific
Ada exception, any re-evaluation of that catchpoint (for instance
a re-evaluation performed after a shared library got mapped by the
inferior) fails. For instance, with any Ada program:

    (gdb)
    -catch-exception -e program_error
    ^done,bkptno="1",bkpt={[...]}
    (gdb)
    -exec-run
    =thread-group-started,id="i1",pid="28315"
    =thread-created,id="1",group-id="i1"
    ^running
    *running,thread-id="all"
    (gdb)
    =library-loaded,[...]
    &"warning: failed to reevaluate internal exception condition for catchpoint 1: No definition of \"exec\" in current context.\n"
    &"warning: failed to reevaluate internal exception condition for catchpoint 1: No definition of \"exec\" in current context.\n"
    [...]

The same is true if using an Ada exception catchpoint.

The problem comes from the fact that that we deallocate the strings
given as arguments to create_ada_exception_catchpoint, while the latter
just makes shallow copies of those strings, thus creating dandling
pointers.

This patch fixes the issue by passing freshly allocated strings to
create_ada_exception_catchpoint, while at the same time updating
create_ada_exception_catchpoint's documentation to make it clear
that deallocating the strings is no longer the responsibility of
the caller.

gdb/ChangeLog:

        * ada-lang.c (create_ada_exception_catchpoint): Enhance
        the documentation of fields "except_string" and "condition".
        * mi/mi-cmd-catch.c (mi_cmd_catch_assert): Reallocate
        CONDITION on the heap before passing it to
        create_ada_exception_catchpoint.
        (mi_cmd_catch_exception): Likewise for EXCEPTION_NAME and
        CONDITION.

gdb/testsuite/ChangeLog:

        * gdb.ada/mi_ex_cond: New testcase.

Tested on x86_64-linux.  The "-break-list" test FAILs without
this patch.
2013-11-11 19:19:07 +04:00

242 lines
5.6 KiB
C

/* MI Command Set - catch commands.
Copyright (C) 2012-2013 Free Software Foundation, Inc.
Contributed by Intel Corporation.
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 "arch-utils.h"
#include "breakpoint.h"
#include "gdb.h"
#include "libiberty.h"
#include "ada-lang.h"
#include "mi-cmds.h"
#include "mi-getopt.h"
#include "mi-cmd-break.h"
/* Handler for the -catch-assert command. */
void
mi_cmd_catch_assert (char *cmd, char *argv[], int argc)
{
struct gdbarch *gdbarch = get_current_arch();
char *condition = NULL;
int enabled = 1;
int temp = 0;
int oind = 0;
char *oarg;
enum opt
{
OPT_CONDITION, OPT_DISABLED, OPT_TEMP,
};
static const struct mi_opt opts[] =
{
{ "c", OPT_CONDITION, 1},
{ "d", OPT_DISABLED, 0 },
{ "t", OPT_TEMP, 0 },
{ 0, 0, 0 }
};
for (;;)
{
int opt = mi_getopt ("-catch-assert", argc, argv, opts,
&oind, &oarg);
if (opt < 0)
break;
switch ((enum opt) opt)
{
case OPT_CONDITION:
condition = oarg;
break;
case OPT_DISABLED:
enabled = 0;
break;
case OPT_TEMP:
temp = 1;
break;
}
}
/* This command does not accept any argument. Make sure the user
did not provide any. */
if (oind != argc)
error (_("Invalid argument: %s"), argv[oind]);
setup_breakpoint_reporting ();
/* create_ada_exception_catchpoint needs CONDITION to be xstrdup'ed,
and will assume control of its lifetime. */
if (condition != NULL)
condition = xstrdup (condition);
create_ada_exception_catchpoint (gdbarch, ada_catch_assert,
NULL, condition, temp, enabled, 0);
}
/* Handler for the -catch-exception command. */
void
mi_cmd_catch_exception (char *cmd, char *argv[], int argc)
{
struct gdbarch *gdbarch = get_current_arch();
char *condition = NULL;
int enabled = 1;
char *exception_name = NULL;
int temp = 0;
enum ada_exception_catchpoint_kind ex_kind = ada_catch_exception;
int oind = 0;
char *oarg;
enum opt
{
OPT_CONDITION, OPT_DISABLED, OPT_EXCEPTION_NAME, OPT_TEMP,
OPT_UNHANDLED,
};
static const struct mi_opt opts[] =
{
{ "c", OPT_CONDITION, 1},
{ "d", OPT_DISABLED, 0 },
{ "e", OPT_EXCEPTION_NAME, 1 },
{ "t", OPT_TEMP, 0 },
{ "u", OPT_UNHANDLED, 0},
{ 0, 0, 0 }
};
for (;;)
{
int opt = mi_getopt ("-catch-exception", argc, argv, opts,
&oind, &oarg);
if (opt < 0)
break;
switch ((enum opt) opt)
{
case OPT_CONDITION:
condition = oarg;
break;
case OPT_DISABLED:
enabled = 0;
break;
case OPT_EXCEPTION_NAME:
exception_name = oarg;
break;
case OPT_TEMP:
temp = 1;
break;
case OPT_UNHANDLED:
ex_kind = ada_catch_exception_unhandled;
break;
}
}
/* This command does not accept any argument. Make sure the user
did not provide any. */
if (oind != argc)
error (_("Invalid argument: %s"), argv[oind]);
/* Specifying an exception name does not make sense when requesting
an unhandled exception breakpoint. */
if (ex_kind == ada_catch_exception_unhandled && exception_name != NULL)
error (_("\"-e\" and \"-u\" are mutually exclusive"));
setup_breakpoint_reporting ();
/* create_ada_exception_catchpoint needs EXCEPTION_NAME and CONDITION
to be xstrdup'ed, and will assume control of their lifetime. */
if (exception_name != NULL)
exception_name = xstrdup (exception_name);
if (condition != NULL)
condition = xstrdup (condition);
create_ada_exception_catchpoint (gdbarch, ex_kind,
exception_name, condition,
temp, enabled, 0);
}
/* Common path for the -catch-load and -catch-unload. */
static void
mi_catch_load_unload (int load, char *argv[], int argc)
{
struct cleanup *back_to;
const char *actual_cmd = load ? "-catch-load" : "-catch-unload";
int temp = 0;
int enabled = 1;
int oind = 0;
char *oarg;
enum opt
{
OPT_TEMP,
OPT_DISABLED,
};
static const struct mi_opt opts[] =
{
{ "t", OPT_TEMP, 0 },
{ "d", OPT_DISABLED, 0 },
{ 0, 0, 0 }
};
for (;;)
{
int opt = mi_getopt (actual_cmd, argc, argv, opts,
&oind, &oarg);
if (opt < 0)
break;
switch ((enum opt) opt)
{
case OPT_TEMP:
temp = 1;
break;
case OPT_DISABLED:
enabled = 0;
break;
}
}
if (oind >= argc)
error (_("-catch-load/unload: Missing <library name>"));
if (oind < argc -1)
error (_("-catch-load/unload: Garbage following the <library name>"));
back_to = setup_breakpoint_reporting ();
add_solib_catchpoint (argv[oind], load, temp, enabled);
do_cleanups (back_to);
}
/* Handler for the -catch-load. */
void
mi_cmd_catch_load (char *cmd, char *argv[], int argc)
{
mi_catch_load_unload (1, argv, argc);
}
/* Handler for the -catch-unload. */
void
mi_cmd_catch_unload (char *cmd, char *argv[], int argc)
{
mi_catch_load_unload (0, argv, argc);
}