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* cleanups.h: New file.

Browse Source 
* cleanups.c: New file.
	* Makefile.in (SFILES): Add cleanups.c.
	(HFILES_NO_SRCDIR): Add cleanups.h.
	(COMMON_OBS): Add cleanups.o.
	* defs.h (struct cleanup): Moved to cleanups.h.
	(do_cleanups,do_final_cleanups): Ditto.
	(discard_cleanups,discard_final_cleanups): Ditto
	(make_cleanup,make_cleanup_dtor,make_final_cleanup): Ditto.
	(save_cleanups,save_final_cleanups): Ditto.
	(restore_cleanups,restore_final_cleanups): Ditto.
	(null_cleanup): Ditto.
	(make_my_cleanup,make_my_cleanup2): Ditto.
	(discard_my_cleanups,save_my_cleanups,restore_my_cleanups): Ditto.
	* utils.c (cleanup_chain,final_cleanup_chain): Moved to cleanups.c.
	(do_cleanups,do_final_cleanups): Ditto.
	(discard_cleanups,discard_final_cleanups): Ditto
	(make_cleanup,make_cleanup_dtor,make_final_cleanup): Ditto.
	(save_cleanups,save_final_cleanups): Ditto.
	(restore_cleanups,restore_final_cleanups): Ditto.
	(null_cleanup): Ditto.
	(make_my_cleanup,make_my_cleanup2): Ditto.
	(discard_my_cleanups,save_my_cleanups,restore_my_cleanups): Ditto.
This commit is contained in:
Doug Evans 2012-04-17 21:13:20 +00:00
parent e0088cfdc7
commit c27f573840
6 changed files with 372 additions and 234 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
gdb/ChangeLog
View File

@ -1,5 +1,29 @@
2012-04-17 Doug Evans <dje@google.com>
* cleanups.h: New file.
* cleanups.c: New file.
* Makefile.in (SFILES): Add cleanups.c.
(HFILES_NO_SRCDIR): Add cleanups.h.
(COMMON_OBS): Add cleanups.o.
* defs.h (struct cleanup): Moved to cleanups.h.
(do_cleanups,do_final_cleanups): Ditto.
(discard_cleanups,discard_final_cleanups): Ditto
(make_cleanup,make_cleanup_dtor,make_final_cleanup): Ditto.
(save_cleanups,save_final_cleanups): Ditto.
(restore_cleanups,restore_final_cleanups): Ditto.
(null_cleanup): Ditto.
(make_my_cleanup,make_my_cleanup2): Ditto.
(discard_my_cleanups,save_my_cleanups,restore_my_cleanups): Ditto.
* utils.c (cleanup_chain,final_cleanup_chain): Moved to cleanups.c.
(do_cleanups,do_final_cleanups): Ditto.
(discard_cleanups,discard_final_cleanups): Ditto
(make_cleanup,make_cleanup_dtor,make_final_cleanup): Ditto.
(save_cleanups,save_final_cleanups): Ditto.
(restore_cleanups,restore_final_cleanups): Ditto.
(null_cleanup): Ditto.
(make_my_cleanup,make_my_cleanup2): Ditto.
(discard_my_cleanups,save_my_cleanups,restore_my_cleanups): Ditto.
* utils.c (make_cleanup_freeargv): Use make_cleanup instead of
make_my_cleanup.
(make_cleanup_dyn_string_delete): Ditto.

6
gdb/Makefile.in
View File

@ -690,7 +690,7 @@ SFILES = ada-exp.y ada-lang.c ada-typeprint.c ada-valprint.c ada-tasks.c \
bfd-target.c \
block.c blockframe.c breakpoint.c buildsym.c \
c-exp.y c-lang.c c-typeprint.c c-valprint.c \
charset.c cli-out.c coffread.c coff-pe-read.c \
charset.c cleanups.c cli-out.c coffread.c coff-pe-read.c \
complaints.c completer.c continuations.c corefile.c corelow.c \
cp-abi.c cp-support.c cp-namespace.c cp-valprint.c \
d-lang.c d-valprint.c \
@ -783,7 +783,7 @@ objfiles.h vec.h disasm.h mips-tdep.h ser-base.h \
gdb_curses.h bfd-target.h memattr.h inferior.h ax.h dummy-frame.h \
inflow.h fbsd-nat.h ia64-libunwind-tdep.h completer.h inf-ttrace.h \
solib-target.h gdb_vfork.h alpha-tdep.h dwarf2expr.h \
m2-lang.h stack.h charset.h addrmap.h command.h solist.h source.h \
m2-lang.h stack.h charset.h cleanups.h addrmap.h command.h solist.h source.h \
target.h prologue-value.h cp-abi.h tui/tui-hooks.h tui/tui.h \
tui/tui-file.h tui/tui-command.h tui/tui-disasm.h tui/tui-wingeneral.h \
tui/tui-windata.h tui/tui-data.h tui/tui-win.h tui/tui-stack.h \
@ -858,7 +858,7 @@ COMMON_OBS = $(DEPFILES) $(CONFIG_OBS) $(YYOBJ) \
auto-load.o auxv.o \
agent.o \
bfd-target.o \
blockframe.o breakpoint.o findvar.o regcache.o \
blockframe.o breakpoint.o findvar.o regcache.o cleanups.o \
charset.o continuations.o corelow.o disasm.o dummy-frame.o dfp.o \
source.o value.o eval.o valops.o valarith.o valprint.o printcmd.o \
block.o symtab.o psymtab.o symfile.o symmisc.o linespec.o dictionary.o \

245
gdb/cleanups.c Normal file
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@ -0,0 +1,245 @@
/* Cleanup routines for GDB, the GNU debugger.
Copyright (C) 1986, 1988-2012 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"
/* Chain of cleanup actions established with make_cleanup,
to be executed if an error happens. */
/* Cleaned up after a failed command. */
static struct cleanup *cleanup_chain;
/* Cleaned up when gdb exits. */
static struct cleanup *final_cleanup_chain;
/* Main worker routine to create a cleanup.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
FUNCTION is the function to call to perform the cleanup.
ARG is passed to FUNCTION when called.
FREE_ARG, if non-NULL, is called after the cleanup is performed.
The result is a pointer to the previous chain pointer
to be passed later to do_cleanups or discard_cleanups. */
struct cleanup *
make_my_cleanup2 (struct cleanup **pmy_chain, make_cleanup_ftype *function,
void *arg, void (*free_arg) (void *))
{
struct cleanup *new
= (struct cleanup *) xmalloc (sizeof (struct cleanup));
struct cleanup *old_chain = *pmy_chain;
new->next = *pmy_chain;
new->function = function;
new->free_arg = free_arg;
new->arg = arg;
*pmy_chain = new;
return old_chain;
}
/* Worker routine to create a cleanup without a destructor.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
FUNCTION is the function to call to perform the cleanup.
ARG is passed to FUNCTION when called.
The result is a pointer to the previous chain pointer
to be passed later to do_cleanups or discard_cleanups. */
struct cleanup *
make_my_cleanup (struct cleanup **pmy_chain, make_cleanup_ftype *function,
void *arg)
{
return make_my_cleanup2 (pmy_chain, function, arg, NULL);
}
/* Add a new cleanup to the cleanup_chain,
and return the previous chain pointer
to be passed later to do_cleanups or discard_cleanups.
Args are FUNCTION to clean up with, and ARG to pass to it. */
struct cleanup *
make_cleanup (make_cleanup_ftype *function, void *arg)
{
return make_my_cleanup (&cleanup_chain, function, arg);
}
/* Same as make_cleanup except also includes TDOR, a destructor to free ARG.
DTOR is invoked when the cleanup is performed or when it is discarded. */
struct cleanup *
make_cleanup_dtor (make_cleanup_ftype *function, void *arg,
void (*dtor) (void *))
{
return make_my_cleanup2 (&cleanup_chain,
function, arg, dtor);
}
/* Same as make_cleanup except the cleanup is added to final_cleanup_chain. */
struct cleanup *
make_final_cleanup (make_cleanup_ftype *function, void *arg)
{
return make_my_cleanup (&final_cleanup_chain, function, arg);
}
/* Worker routine to perform cleanups.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
OLD_CHAIN is the result of a "make" cleanup routine.
Cleanups are performed until we get back to the old end of the chain. */
static void
do_my_cleanups (struct cleanup **pmy_chain,
struct cleanup *old_chain)
{
struct cleanup *ptr;
while ((ptr = *pmy_chain) != old_chain)
{
*pmy_chain = ptr->next; /* Do this first in case of recursion. */
(*ptr->function) (ptr->arg);
if (ptr->free_arg)
(*ptr->free_arg) (ptr->arg);
xfree (ptr);
}
}
/* Discard cleanups and do the actions they describe
until we get back to the point OLD_CHAIN in the cleanup_chain. */
void
do_cleanups (struct cleanup *old_chain)
{
do_my_cleanups (&cleanup_chain, old_chain);
}
/* Discard cleanups and do the actions they describe
until we get back to the point OLD_CHAIN in the final_cleanup_chain. */
void
do_final_cleanups (struct cleanup *old_chain)
{
do_my_cleanups (&final_cleanup_chain, old_chain);
}
/* Main worker routine to discard cleanups.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
OLD_CHAIN is the result of a "make" cleanup routine.
Cleanups are discarded until we get back to the old end of the chain. */
void
discard_my_cleanups (struct cleanup **pmy_chain,
struct cleanup *old_chain)
{
struct cleanup *ptr;
while ((ptr = *pmy_chain) != old_chain)
{
*pmy_chain = ptr->next;
if (ptr->free_arg)
(*ptr->free_arg) (ptr->arg);
xfree (ptr);
}
}
/* Discard cleanups, not doing the actions they describe,
until we get back to the point OLD_CHAIN in the cleanup chain. */
void
discard_cleanups (struct cleanup *old_chain)
{
discard_my_cleanups (&cleanup_chain, old_chain);
}
/* Discard final cleanups, not doing the actions they describe,
until we get back to the point OLD_CHAIN in the final cleanup chain. */
void
discard_final_cleanups (struct cleanup *old_chain)
{
discard_my_cleanups (&final_cleanup_chain, old_chain);
}
/* Main worker routine to save cleanups.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
The chain is emptied and the result is a pointer to the old chain. */
struct cleanup *
save_my_cleanups (struct cleanup **pmy_chain)
{
struct cleanup *old_chain = *pmy_chain;
*pmy_chain = 0;
return old_chain;
}
/* Set the cleanup_chain to 0, and return the old cleanup_chain. */
struct cleanup *
save_cleanups (void)
{
return save_my_cleanups (&cleanup_chain);
}
/* Set the final_cleanup_chain to 0, and return the old
final_cleanup_chain. */
struct cleanup *
save_final_cleanups (void)
{
return save_my_cleanups (&final_cleanup_chain);
}
/* Main worker routine to save cleanups.
PMY_CHAIN is a pointer to either cleanup_chain or final_cleanup_chain.
The chain is restored from CHAIN. */
void
restore_my_cleanups (struct cleanup **pmy_chain, struct cleanup *chain)
{
*pmy_chain = chain;
}
/* Restore the cleanup chain from a previously saved chain. */
void
restore_cleanups (struct cleanup *chain)
{
restore_my_cleanups (&cleanup_chain, chain);
}
/* Restore the final cleanup chain from a previously saved chain. */
void
restore_final_cleanups (struct cleanup *chain)
{
restore_my_cleanups (&final_cleanup_chain, chain);
}
/* Provide a known function that does nothing, to use as a base for
a possibly long chain of cleanups. This is useful where we
use the cleanup chain for handling normal cleanups as well as dealing
with cleanups that need to be done as a result of a call to error().
In such cases, we may not be certain where the first cleanup is, unless
we have a do-nothing one to always use as the base. */
void
null_cleanup (void *arg)
{
}

94
gdb/cleanups.h Normal file
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@ -0,0 +1,94 @@
/* Cleanups.
Copyright (C) 1986, 1988-2005, 2007-2012 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/>. */
#ifndef CLEANUPS_H
#define CLEANUPS_H
/* The cleanup list records things that have to be undone
if an error happens (descriptors to be closed, memory to be freed, etc.)
Each link in the chain records a function to call and an
argument to give it.
Use make_cleanup to add an element to the cleanup chain.
Use do_cleanups to do all cleanup actions back to a given
point in the chain. Use discard_cleanups to remove cleanups
from the chain back to a given point, not doing them.
If the argument is pointer to allocated memory, then you need
to additionally set the 'free_arg' member to a function that will
free that memory. This function will be called both when the cleanup
is executed and when it's discarded. */
struct cleanup
{
struct cleanup *next;
void (*function) (void *);
void (*free_arg) (void *);
void *arg;
};
/* NOTE: cagney/2000-03-04: This typedef is strictly for the
make_cleanup function declarations below. Do not use this typedef
as a cast when passing functions into the make_cleanup() code.
Instead either use a bounce function or add a wrapper function.
Calling a f(char*) function with f(void*) is non-portable. */
typedef void (make_cleanup_ftype) (void *);
/* WARNING: The result of the "make cleanup" routines is not the intuitive
choice of being a handle on the just-created cleanup. Instead it is an
opaque handle of the cleanup mechanism and represents all cleanups created
from that point onwards. */
extern struct cleanup *make_cleanup (make_cleanup_ftype *, void *);
extern struct cleanup *make_cleanup_dtor (make_cleanup_ftype *, void *,
void (*dtor) (void *));
extern struct cleanup *make_final_cleanup (make_cleanup_ftype *, void *);
extern struct cleanup *make_my_cleanup (struct cleanup **,
make_cleanup_ftype *, void *);
extern struct cleanup *make_my_cleanup2 (struct cleanup **,
make_cleanup_ftype *, void *,
void (*free_arg) (void *));
/* A special value to pass to do_cleanups and do_final_cleanups
to tell them to do all cleanups. */
#define ALL_CLEANUPS ((struct cleanup *)0)
extern void do_cleanups (struct cleanup *);
extern void do_final_cleanups (struct cleanup *);
extern void discard_cleanups (struct cleanup *);
extern void discard_final_cleanups (struct cleanup *);
extern void discard_my_cleanups (struct cleanup **, struct cleanup *);
extern struct cleanup *save_cleanups (void);
extern struct cleanup *save_final_cleanups (void);
extern struct cleanup *save_my_cleanups (struct cleanup **);
extern void restore_cleanups (struct cleanup *);
extern void restore_final_cleanups (struct cleanup *);
extern void restore_my_cleanups (struct cleanup **, struct cleanup *);
/* A no-op cleanup.
This is useful when you want to establish a known reference point
to pass to do_cleanups. */
extern void null_cleanup (void *);
#endif /* CLEANUPS_H */

63
gdb/defs.h
View File

@ -251,29 +251,6 @@ enum return_value_convention
RETURN_VALUE_ABI_PRESERVES_ADDRESS,
};
/* the cleanup list records things that have to be undone
if an error happens (descriptors to be closed, memory to be freed, etc.)
Each link in the chain records a function to call and an
argument to give it.
Use make_cleanup to add an element to the cleanup chain.
Use do_cleanups to do all cleanup actions back to a given
point in the chain. Use discard_cleanups to remove cleanups
from the chain back to a given point, not doing them.
If the argument is pointer to allocated memory, then you need
to additionally set the 'free_arg' member to a function that will
free that memory. This function will be called both when the cleanup
is executed and when it's discarded. */
struct cleanup
{
struct cleanup *next;
void (*function) (void *);
void (*free_arg) (void *);
void *arg;
};
/* vec.h-style vectors of strings want a typedef for char * or const char *. */
typedef char * char_ptr;
@ -313,26 +290,9 @@ extern void set_display_time (int);
extern void set_display_space (int);
#define ALL_CLEANUPS ((struct cleanup *)0)
/* Cleanup utilities. */
extern void do_cleanups (struct cleanup *);
extern void do_final_cleanups (struct cleanup *);
extern void discard_cleanups (struct cleanup *);
extern void discard_final_cleanups (struct cleanup *);
extern void discard_my_cleanups (struct cleanup **, struct cleanup *);
/* NOTE: cagney/2000-03-04: This typedef is strictly for the
make_cleanup function declarations below. Do not use this typedef
as a cast when passing functions into the make_cleanup() code.
Instead either use a bounce function or add a wrapper function.
Calling a f(char*) function with f(void*) is non-portable. */
typedef void (make_cleanup_ftype) (void *);
extern struct cleanup *make_cleanup (make_cleanup_ftype *, void *);
extern struct cleanup *make_cleanup_dtor (make_cleanup_ftype *, void *,
void (*dtor) (void *));
#include "cleanups.h"
extern struct cleanup *make_cleanup_freeargv (char **);
@ -374,29 +334,10 @@ extern struct cleanup *make_cleanup_value_free (struct value *);
struct so_list;
extern struct cleanup *make_cleanup_free_so (struct so_list *so);
extern struct cleanup *make_final_cleanup (make_cleanup_ftype *, void *);
extern struct cleanup *make_my_cleanup (struct cleanup **,
make_cleanup_ftype *, void *);
extern struct cleanup *make_cleanup_htab_delete (htab_t htab);
extern struct cleanup *make_my_cleanup2 (struct cleanup **,
make_cleanup_ftype *, void *,
void (*free_arg) (void *));
extern struct cleanup *save_cleanups (void);
extern struct cleanup *save_final_cleanups (void);
extern struct cleanup *save_my_cleanups (struct cleanup **);
extern void restore_cleanups (struct cleanup *);
extern void restore_final_cleanups (struct cleanup *);
extern void restore_my_cleanups (struct cleanup **, struct cleanup *);
extern void free_current_contents (void *);
extern void null_cleanup (void *);
extern struct cleanup *make_command_stats_cleanup (int);
extern int myread (int, char *, int);

174
gdb/utils.c
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@ -99,8 +99,6 @@ static void vfprintf_maybe_filtered (struct ui_file *, const char *,
static void fputs_maybe_filtered (const char *, struct ui_file *, int);
static void do_my_cleanups (struct cleanup **, struct cleanup *);
static void prompt_for_continue (void);
static void set_screen_size (void);
@ -110,12 +108,6 @@ static void set_width (void);
static int debug_timestamp = 0;
/* Chain of cleanup actions established with make_cleanup,
to be executed if an error happens. */
static struct cleanup *cleanup_chain; /* cleaned up after a failed command */
static struct cleanup *final_cleanup_chain; /* cleaned up when gdb exits */
/* Nonzero if we have job control. */
int job_control;
@ -172,31 +164,11 @@ show_pagination_enabled (struct ui_file *file, int from_tty,
}
/* Cleanup utilities.
/* Add a new cleanup to the cleanup_chain,
and return the previous chain pointer
to be passed later to do_cleanups or discard_cleanups.
Args are FUNCTION to clean up with, and ARG to pass to it. */
struct cleanup *
make_cleanup (make_cleanup_ftype *function, void *arg)
{
return make_my_cleanup (&cleanup_chain, function, arg);
}
struct cleanup *
make_cleanup_dtor (make_cleanup_ftype *function, void *arg,
void (*dtor) (void *))
{
return make_my_cleanup2 (&cleanup_chain,
function, arg, dtor);
}
struct cleanup *
make_final_cleanup (make_cleanup_ftype *function, void *arg)
{
return make_my_cleanup (&final_cleanup_chain, function, arg);
}
These are not defined in cleanups.c (nor declared in cleanups.h)
because while they use the "cleanup API" they are not part of the
"cleanup API". */
static void
do_freeargv (void *arg)
@ -484,132 +456,6 @@ make_cleanup_free_so (struct so_list *so)
return make_cleanup (do_free_so, so);
}
struct cleanup *
make_my_cleanup2 (struct cleanup **pmy_chain, make_cleanup_ftype *function,
void *arg, void (*free_arg) (void *))
{
struct cleanup *new
= (struct cleanup *) xmalloc (sizeof (struct cleanup));
struct cleanup *old_chain = *pmy_chain;
new->next = *pmy_chain;
new->function = function;
new->free_arg = free_arg;
new->arg = arg;
*pmy_chain = new;
return old_chain;
}
struct cleanup *
make_my_cleanup (struct cleanup **pmy_chain, make_cleanup_ftype *function,
void *arg)
{
return make_my_cleanup2 (pmy_chain, function, arg, NULL);
}
/* Discard cleanups and do the actions they describe
until we get back to the point OLD_CHAIN in the cleanup_chain. */
void
do_cleanups (struct cleanup *old_chain)
{
do_my_cleanups (&cleanup_chain, old_chain);
}
void
do_final_cleanups (struct cleanup *old_chain)
{
do_my_cleanups (&final_cleanup_chain, old_chain);
}
static void
do_my_cleanups (struct cleanup **pmy_chain,
struct cleanup *old_chain)
{
struct cleanup *ptr;
while ((ptr = *pmy_chain) != old_chain)
{
*pmy_chain = ptr->next; /* Do this first in case of recursion. */
(*ptr->function) (ptr->arg);
if (ptr->free_arg)
(*ptr->free_arg) (ptr->arg);
xfree (ptr);
}
}
/* Discard cleanups, not doing the actions they describe,
until we get back to the point OLD_CHAIN in the cleanup_chain. */
void
discard_cleanups (struct cleanup *old_chain)
{
discard_my_cleanups (&cleanup_chain, old_chain);
}
void
discard_final_cleanups (struct cleanup *old_chain)
{
discard_my_cleanups (&final_cleanup_chain, old_chain);
}
void
discard_my_cleanups (struct cleanup **pmy_chain,
struct cleanup *old_chain)
{
struct cleanup *ptr;
while ((ptr = *pmy_chain) != old_chain)
{
*pmy_chain = ptr->next;
if (ptr->free_arg)
(*ptr->free_arg) (ptr->arg);
xfree (ptr);
}
}
/* Set the cleanup_chain to 0, and return the old cleanup chain. */
struct cleanup *
save_cleanups (void)
{
return save_my_cleanups (&cleanup_chain);
}
struct cleanup *
save_final_cleanups (void)
{
return save_my_cleanups (&final_cleanup_chain);
}
struct cleanup *
save_my_cleanups (struct cleanup **pmy_chain)
{
struct cleanup *old_chain = *pmy_chain;
*pmy_chain = 0;
return old_chain;
}
/* Restore the cleanup chain from a previously saved chain. */
void
restore_cleanups (struct cleanup *chain)
{
restore_my_cleanups (&cleanup_chain, chain);
}
void
restore_final_cleanups (struct cleanup *chain)
{
restore_my_cleanups (&final_cleanup_chain, chain);
}
void
restore_my_cleanups (struct cleanup **pmy_chain, struct cleanup *chain)
{
*pmy_chain = chain;
}
/* This function is useful for cleanups.
Do
@ -633,18 +479,6 @@ free_current_contents (void *ptr)
}
}
/* Provide a known function that does nothing, to use as a base for
a possibly long chain of cleanups. This is useful where we
use the cleanup chain for handling normal cleanups as well as dealing
with cleanups that need to be done as a result of a call to error().
In such cases, we may not be certain where the first cleanup is, unless
we have a do-nothing one to always use as the base. */
void
null_cleanup (void *arg)
{
}
/* If nonzero, display time usage both at startup and for each command. */
static int display_time;