sfexit.c

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/* Copyright (c) Colorado School of Mines, 2006.*/
/* All rights reserved.                       */

#include	"sfhdr.h"

/*
**	Any required functions for process exiting.
**	Written by Kiem-Phong Vo
*/

#if PACKAGE_ast
int	_AST_already_has_them;
#else

#if !_lib_atexit
#if _lib_onexit

#if __STD_C
int atexit(void (*exitf)(void))
#else
int atexit(exitf)
void	(*exitf)();
#endif
{
#if _lib_onexit
	return onexit(exitf);
#endif
}

#else /* !_lib_onexit */

typedef struct _exit_s
{	struct _exit_s*	next;
	void		(*exitf)_ARG_((void));
} Exit_t;
static Exit_t*	Exit;

#if __STD_C
atexit(void (*exitf)(void))
#else
atexit(exitf)
void	(*exitf)();
#endif
{	Exit_t*	e;
	int	rv;

	(void)vtmtxlock(_Sfmutex);

	if(!(e = (Exit_t*)malloc(sizeof(Exit_t))) )
		rv = -1;
	else
	{	e->exitf = exitf;
		e->next = Exit;
		Exit = e;
		rv = 0;
	}

	(void)vtmtxunlock(_Sfmutex);

	return rv;
}

#if _exit_cleanup
/* since exit() calls _cleanup(), we only need to redefine _cleanup() */
#if __STD_C
_cleanup(void)
#else
_cleanup()
#endif
{
	Exit_t*	e;
	for(e = Exit; e; e = e->next)
		(*e->exitf)();
	if(_Sfcleanup)
		(*_Sfcleanup)();
}

#else

/* in this case, we have to redefine exit() itself */
#if __STD_C
void exit(int type)
#else
void exit(type)
int	type;
#endif
{
	Exit_t*	e;
	for(e = Exit; e; e = e->next)
		(*e->exitf)();
	_exit(type);
}
#endif /* _exit_cleanup */

#endif	/* _lib_onexit */

#endif /* !_lib_atexit */

#if _lib_waitpid
int	_Sf_no_need_for_waitpid;
#else

/* we need to supply our own waitpid here so that sfpclose() can wait
** for the right process to die.
*/
typedef struct _wait_
{
	int		pid;
	int		status;
	struct _wait_*	next;
} Waitpid_t;

static Waitpid_t*	Wait;

#if __STD_C
waitpid(int pid, int* status, int options)
#else
waitpid(pid, status, options)
int	pid;
int*	status;
int	options;
#endif
{
	int		id, ps;
	Waitpid_t*	w;
	Waitpid_t*	last;

	/* we don't know options */
	if(options != 0)
		return -1;

	(void)vtmtxlock(_Sfmutex);

	for(w = Wait, last = NIL(Waitpid_t*); w; last = w, w = w->next)
	{	if(pid > 0 && pid != w->pid)
			continue;

		if(last)
			last->next = w->next;
		else	Wait = w->next;
		if(status)
			*status = w->status;
		pid = w->pid;
		free(w);

		(void)vtmtxunlock(_Sfmutex);
		return pid;
	}

	while((id = wait(&ps)) >= 0)
	{	if(pid <= 0 || id == pid)
		{	if(status)
				*status = ps;

			(void)vtmtxunlock(_Sfmutex);
			return pid;
		}

		if(!(w = (Waitpid_t*)malloc(sizeof(Waitpid_t))) )
			continue;

		w->pid = id;
		w->status = ps;
		w->next = Wait;
		Wait = w;
	}

	(void)vtmtxunlock(_Sfmutex);
	return -1;
}

#endif /*_lib_waitpid*/

#endif /*!PACKAGE_ast*/