usr/src/uts/common/sys/pathconf.h

root/usr/src/uts/common/sys/pathconf.h
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *      Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
 *      Use is subject to license terms.
 */

#ifndef _SYS_PATHCONF_H
#define _SYS_PATHCONF_H

/*      pathconf.h 1.9 89/06/26 SMI     */

#include <sys/unistd.h>
#include <sys/types.h>

#ifdef  __cplusplus
extern "C" {
#endif

/*
 * POSIX pathconf information
 *
 * static pathconf kludge notes:
 *      For NFSv2 servers, we've added a vop (vop_cntl) to dig out pathconf
 *      information.  The mount program asked for the information from
 *      a remote mountd daemon.  If it gets it, it passes the info
 *      down in a new args field.  The info is passed in the struct below
 *      in nfsargs.pathconf.  There's a new NFS mount flag so that you know
 *      this is happening.  NFS stores the information locally; when a
 *      pathconf request is made, the request is intercepted at the client
 *      and the information is retrieved from the struct passed down by
 *      mount. It's a kludge that will go away as soon
 *      as we can ask the nfs protocol these sorts of questions (NFSr3).
 *      All code is noted by "static pathconf kludge" comments and is
 *      restricted to nfs code in the kernel.
 */

#define _BITS           (8 * sizeof (short))
#define _PC_N           ((_PC_LAST + _BITS - 1) / _BITS)
#define _PC_ISSET(n, a) (a[(n) / _BITS] & (1 << ((n) % _BITS)))
#define _PC_SET(n, a)   (a[(n) / _BITS] |= (1 << ((n) % _BITS)))
#define _PC_ERROR       0

struct  pathcnf {
        /*
         * pathconf() information
         */
        int             pc_link_max;    /* max links allowed */
        short           pc_max_canon;   /* max line len for a tty */
        short           pc_max_input;   /* input a tty can eat all once */
        short           pc_name_max;    /* max file name length (dir entry) */
        short           pc_path_max;    /* path name len (/x/y/z/...) */
        short           pc_pipe_buf;    /* size of a pipe (bytes) */
        uchar_t         pc_vdisable;    /* safe char to turn off c_cc[i] */
        char            pc_xxx;         /* alignment padding; cc_t == char */
        short           pc_mask[_PC_N]; /* see below */
#ifdef  _KERNEL
        short           pc_refcnt;      /* number of mounts that use this */
        struct pathcnf  *pc_next;       /* linked list */
#endif
};

#ifdef _SYSCALL32
struct  pathcnf32 {
        /*
         * pathconf() information
         */
        int32_t         pc_link_max;    /* max links allowed */
        int16_t         pc_max_canon;   /* max line len for a tty */
        int16_t         pc_max_input;   /* input a tty can eat all once */
        int16_t         pc_name_max;    /* max file name length (dir entry) */
        int16_t         pc_path_max;    /* path name len (/x/y/z/...) */
        int16_t         pc_pipe_buf;    /* size of a pipe (bytes) */
        uint8_t         pc_vdisable;    /* safe char to turn off c_cc[i] */
        int8_t          pc_xxx;         /* alignment padding; cc_t == char */
        int16_t         pc_mask[_PC_N]; /* see below */
#ifdef  _KERNEL
        int16_t         pc_refcnt;      /* number of mounts that use this */
        caddr32_t       pc_next;        /* linked list */
#endif
};
#endif /* _SYSCALL32 */

/*
 * pc_mask is used to encode either
 *      a) boolean values (for chown_restricted and no_trunc)
 *      b) errno on/off (for link, canon, input, name, path, and pipe)
 * The _PC_XXX values are defined in unistd.h; they start at 1 and go up
 * sequentially.
 * _PC_ERROR is used as the first bit to indicate total failure
 * (all info invalid).
 * To check for an error something like
 *      _PC_ISSET(_PC_PATHMAX, foo.pc_mask) != 0
 * is used.
 */

/*
 * The size of the non-kernel part of the struct.
 */
#ifdef  _KERNEL
#define PCSIZ           ((size_t)(&(((struct pathcnf *)0)->pc_refcnt)))
#define PCCMP(p1, p2)   bcmp((char *)p1, (char *)p2, PCSIZ)
#endif

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_PATHCONF_H */
Illumos
