[openssh.git] / openbsd-compat / bsd-closefrom.c

/*
 * Copyright (c) 2004-2005 Todd C. Miller <Todd.Miller@courtesan.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"

#ifndef HAVE_CLOSEFROM

#include <sys/types.h>
#include <sys/param.h>
#include <unistd.h>
#include <stdio.h>
#ifdef HAVE_FCNTL_H
# include <fcntl.h>
#endif
#include <limits.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#ifdef HAVE_DIRENT_H
# include <dirent.h>
# define NAMLEN(dirent) strlen((dirent)->d_name)
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# ifdef HAVE_SYS_NDIR_H
#  include <sys/ndir.h>
# endif
# ifdef HAVE_SYS_DIR_H
#  include <sys/dir.h>
# endif
# ifdef HAVE_NDIR_H
#  include <ndir.h>
# endif
#endif

#ifndef OPEN_MAX
# define OPEN_MAX	256
#endif

#if 0
__unused static const char rcsid[] = "$Sudo: closefrom.c,v 1.11 2006/08/17 15:26:54 millert Exp $";
#endif /* lint */

/*
 * Close all file descriptors greater than or equal to lowfd.
 */
#ifdef HAVE_FCNTL_CLOSEM
void
closefrom(int lowfd)
{
    (void) fcntl(lowfd, F_CLOSEM, 0);
}
#else
void
closefrom(int lowfd)
{
    long fd, maxfd;
#if defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
    char fdpath[PATH_MAX], *endp;
    struct dirent *dent;
    DIR *dirp;
    int len;

    /* Check for a /proc/$$/fd directory. */
    len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
    if (len > 0 && (size_t)len <= sizeof(fdpath) && (dirp = opendir(fdpath))) {
	while ((dent = readdir(dirp)) != NULL) {
	    fd = strtol(dent->d_name, &endp, 10);
	    if (dent->d_name != endp && *endp == '\0' &&
		fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
		(void) close((int) fd);
	}
	(void) closedir(dirp);
    } else
#endif
    {
	/*
	 * Fall back on sysconf() or getdtablesize().  We avoid checking
	 * resource limits since it is possible to open a file descriptor
	 * and then drop the rlimit such that it is below the open fd.
	 */
#ifdef HAVE_SYSCONF
	maxfd = sysconf(_SC_OPEN_MAX);
#else
	maxfd = getdtablesize();
#endif /* HAVE_SYSCONF */
	if (maxfd < 0)
	    maxfd = OPEN_MAX;

	for (fd = lowfd; fd < maxfd; fd++)
	    (void) close((int) fd);
    }
}
#endif /* !HAVE_FCNTL_CLOSEM */
#endif /* HAVE_CLOSEFROM */
Commit	Line	Data
419e26e7	1	/*
795e7517	2	* Copyright (c) 2004-2005 Todd C. Miller <Todd.Miller@courtesan.com>
419e26e7	3	*
	4	* Permission to use, copy, modify, and distribute this software for any
	5	* purpose with or without fee is hereby granted, provided that the above
	6	* copyright notice and this permission notice appear in all copies.
	7	*
	8	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	9	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	10	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	11	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	12	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	13	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	14	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	15	*/
	16
	17	#include "includes.h"
	18
	19	#ifndef HAVE_CLOSEFROM
	20
	21	#include <sys/types.h>
	22	#include <sys/param.h>
	23	#include <unistd.h>
	24	#include <stdio.h>
53c337ed	25	#ifdef HAVE_FCNTL_H
	26	# include <fcntl.h>
	27	#endif
419e26e7	28	#include <limits.h>
	29	#include <stdlib.h>
	30	#include <stddef.h>
e204f3ee	31	#include <string.h>
e204f3ee	32	#include <unistd.h>
419e26e7	33	#ifdef HAVE_DIRENT_H
	34	# include <dirent.h>
	35	# define NAMLEN(dirent) strlen((dirent)->d_name)
	36	#else
	37	# define dirent direct
	38	# define NAMLEN(dirent) (dirent)->d_namlen
	39	# ifdef HAVE_SYS_NDIR_H
	40	# include <sys/ndir.h>
	41	# endif
	42	# ifdef HAVE_SYS_DIR_H
	43	# include <sys/dir.h>
	44	# endif
	45	# ifdef HAVE_NDIR_H
	46	# include <ndir.h>
	47	# endif
	48	#endif
	49
	50	#ifndef OPEN_MAX
	51	# define OPEN_MAX 256
	52	#endif
	53
5a1d6300	54	#if 0
795e7517	55	__unused static const char rcsid[] = "$Sudo: closefrom.c,v 1.11 2006/08/17 15:26:54 millert Exp $";
419e26e7	56	#endif /* lint */
	57
	58	/*
	59	* Close all file descriptors greater than or equal to lowfd.
	60	*/
795e7517	61	#ifdef HAVE_FCNTL_CLOSEM
	62	void
	63	closefrom(int lowfd)
	64	{
	65	(void) fcntl(lowfd, F_CLOSEM, 0);
	66	}
	67	#else
419e26e7	68	void
	69	closefrom(int lowfd)
	70	{
	71	long fd, maxfd;
	72	#if defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
	73	char fdpath[PATH_MAX], *endp;
	74	struct dirent *dent;
	75	DIR *dirp;
	76	int len;
	77
	78	/* Check for a /proc/$$/fd directory. */
	79	len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
795e7517	80	if (len > 0 && (size_t)len <= sizeof(fdpath) && (dirp = opendir(fdpath))) {
419e26e7	81	while ((dent = readdir(dirp)) != NULL) {
	82	fd = strtol(dent->d_name, &endp, 10);
	83	if (dent->d_name != endp && *endp == '\0' &&
	84	fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
	85	(void) close((int) fd);
	86	}
	87	(void) closedir(dirp);
	88	} else
	89	#endif
	90	{
	91	/*
	92	* Fall back on sysconf() or getdtablesize(). We avoid checking
	93	* resource limits since it is possible to open a file descriptor
	94	* and then drop the rlimit such that it is below the open fd.
	95	*/
	96	#ifdef HAVE_SYSCONF
	97	maxfd = sysconf(_SC_OPEN_MAX);
	98	#else
	99	maxfd = getdtablesize();
	100	#endif /* HAVE_SYSCONF */
	101	if (maxfd < 0)
	102	maxfd = OPEN_MAX;
	103
	104	for (fd = lowfd; fd < maxfd; fd++)
	105	(void) close((int) fd);
	106	}
	107	}
795e7517	108	#endif /* !HAVE_FCNTL_CLOSEM */
419e26e7	109	#endif /* HAVE_CLOSEFROM */