binutils-gdb/gdb/unittests/scoped_restore-selftests.c
Pedro Alves 9bcb1f1630 Make inferior::detaching a bool, and introduce scoped_restore::release()
I left making inferior::detaching a bool to a separate patch, because
doing that makes a make_cleanup_restore_integer call in
infrun.c:prepare_for_detach no longer compile (passing a 'bool *' when
an 'int *' is expected).  Since we want to get rid of cleanups anyway,
I looked at converting that to a scoped_restore.  However,
prepare_for_detach wants to discard the cleanup on success, and
scoped_restore doesn't have an equivalent for that.  So I added one --
I called it "release()" because it seems like a natural fit in the way
standard components call similarly-spirited methods, and, it's also
what the proposal for a generic scope guard calls it too, AFAICS:

  http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4189.pdf

I've added some scoped_guard unit tests, while at it.

gdb/ChangeLog:
2017-04-19  Pedro Alves  <palves@redhat.com>

	* Makefile.in (SUBDIR_UNITTESTS_SRCS): Add
	unittests/scoped_restore-selftests.c.
	(SUBDIR_UNITTESTS_OBS): Add scoped_restore-selftests.o.
	* common/scoped_restore.h (scoped_restore_base): Make "class".
	(scoped_restore_base::release): New public method.
	(scoped_restore_base::scoped_restore_base): New protected ctor.
	(scoped_restore_base::m_saved_var): New protected field.
	(scoped_restore_tmpl::scoped_restore_tmpl(T*)): Initialize the
	scoped_restore_base base class instead of m_saved_var directly.
	(scoped_restore_tmpl::scoped_restore_tmpl(T*, T2)): Likewise.
	(scoped_restore_tmpl::scoped_restore_tmpl(const
	scoped_restore_tmpl<T>&)): Likewise.
	(scoped_restore_tmpl::~scoped_restore_tmpl): Use the saved_var
	method.
	(scoped_restore_tmpl::saved_var): New method.
	(scoped_restore_tmpl::m_saved_var): Delete.
	* inferior.h (inferior::detaching): Now a bool.
	* infrun.c (prepare_for_detach): Use a scoped_restore instead of a
	cleanup.
	* unittests/scoped_restore-selftests.c: New file.
2017-04-19 13:12:23 +01:00

111 lines
2.8 KiB
C

/* Self tests for scoped_restore for GDB, the GNU debugger.
Copyright (C) 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 "selftest.h"
#include "common/scoped_restore.h"
namespace selftests {
namespace scoped_restore_tests {
struct Base {};
struct Derived : Base {};
static int global;
/* Check that we can return a scoped_restore from a function. Below
we'll make sure this does the right thing. */
static scoped_restore_tmpl<int>
make_scoped_restore_global (int value)
{
return make_scoped_restore (&global, value);
}
static void
run_tests ()
{
/* Test that single-argument make_scoped_restore restores the
original value on scope exit. */
{
int integer = 0;
{
scoped_restore restore = make_scoped_restore (&integer);
SELF_CHECK (integer == 0);
integer = 1;
}
SELF_CHECK (integer == 0);
}
/* Same, with two-argument make_scoped_restore. */
{
int integer = 0;
{
scoped_restore restore = make_scoped_restore (&integer, 1);
SELF_CHECK (integer == 1);
}
SELF_CHECK (integer == 0);
}
/* Test releasing a scoped_restore. */
{
int integer = 0;
{
scoped_restore restore = make_scoped_restore (&integer, 1);
SELF_CHECK (integer == 1);
restore.release ();
}
/* The overridden value should persist. */
SELF_CHECK (integer == 1);
}
/* Test creating a scoped_restore with a value of a type convertible
to T. */
{
Base *base = nullptr;
Derived derived;
{
scoped_restore restore = make_scoped_restore (&base, &derived);
SELF_CHECK (base == &derived);
}
SELF_CHECK (base == nullptr);
}
/* Test calling a function that returns a scoped restore. Makes
sure that if the compiler emits a call to the copy ctor, that we
still do the right thing. */
{
{
SELF_CHECK (global == 0);
scoped_restore restore = make_scoped_restore_global (1);
SELF_CHECK (global == 1);
}
SELF_CHECK (global == 0);
}
}
} /* namespace scoped_restore_tests */
} /* namespace selftests */
void
_initialize_scoped_restore_selftests ()
{
register_self_test (selftests::scoped_restore_tests::run_tests);
}