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

/*
 * Copyright (c) 2004 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>
#include <limits.h>
#include <stdlib.h>
#include <stddef.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

RCSID("$Id: bsd-closefrom.c,v 1.1 2004/08/15 08:41:00 djm Exp $");

#ifndef lint
static const char sudorcsid[] = "$Sudo: closefrom.c,v 1.6 2004/06/01 20:51:56 millert Exp $";
#endif /* lint */

/*
 * Close all file descriptors greater than or equal to lowfd.
 */
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 != -1 && 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_CLOSEFROM */
Commit	Line	Data
f7e15749	1	/*
	2	* Copyright (c) 2004 Todd C. Miller <Todd.Miller@courtesan.com>
	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>
	25	#include <limits.h>
	26	#include <stdlib.h>
	27	#include <stddef.h>
	28	#ifdef HAVE_DIRENT_H
	29	# include <dirent.h>
	30	# define NAMLEN(dirent) strlen((dirent)->d_name)
	31	#else
	32	# define dirent direct
	33	# define NAMLEN(dirent) (dirent)->d_namlen
	34	# ifdef HAVE_SYS_NDIR_H
	35	# include <sys/ndir.h>
	36	# endif
	37	# ifdef HAVE_SYS_DIR_H
	38	# include <sys/dir.h>
	39	# endif
	40	# ifdef HAVE_NDIR_H
	41	# include <ndir.h>
	42	# endif
	43	#endif
	44
	45	#ifndef OPEN_MAX
	46	# define OPEN_MAX 256
	47	#endif
	48
	49	RCSID("$Id: bsd-closefrom.c,v 1.1 2004/08/15 08:41:00 djm Exp $");
	50
	51	#ifndef lint
	52	static const char sudorcsid[] = "$Sudo: closefrom.c,v 1.6 2004/06/01 20:51:56 millert Exp $";
	53	#endif /* lint */
	54
	55	/*
	56	* Close all file descriptors greater than or equal to lowfd.
	57	*/
	58	void
	59	closefrom(int lowfd)
	60	{
	61	long fd, maxfd;
	62	#if defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
	63	char fdpath[PATH_MAX], *endp;
	64	struct dirent *dent;
65	DIR *dirp;
66	int len;
67
68	/* Check for a /proc/$$/fd directory. */
69	len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
70	if (len != -1 && len <= sizeof(fdpath) && (dirp = opendir(fdpath))) {
71	while ((dent = readdir(dirp)) != NULL) {
72	fd = strtol(dent->d_name, &endp, 10);
73	if (dent->d_name != endp && *endp == '\0' &&
74	fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
75	(void) close((int) fd);
76	}
77	(void) closedir(dirp);
78	} else
79	#endif
80	{
81	/*
82	* Fall back on sysconf() or getdtablesize(). We avoid checking
83	* resource limits since it is possible to open a file descriptor
84	* and then drop the rlimit such that it is below the open fd.
85	*/
86	#ifdef HAVE_SYSCONF
87	maxfd = sysconf(_SC_OPEN_MAX);
88	#else
89	maxfd = getdtablesize();
90	#endif /* HAVE_SYSCONF */
91	if (maxfd < 0)
92	maxfd = OPEN_MAX;
93
94	for (fd = lowfd; fd < maxfd; fd++)
95	(void) close((int) fd);
96	}
97	}
98
99	#endif /* HAVE_CLOSEFROM */
100