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

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  *
  22  *      Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
  23  *      Use is subject to license terms.
  24  */
  25
  26 #ifndef _SYS_PATHCONF_H
  27 #define _SYS_PATHCONF_H
  28
  29 /*      pathconf.h 1.9 89/06/26 SMI     */
  30
  31 #include <sys/unistd.h>
  32 #include <sys/types.h>
  33
  34 #ifdef  __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 /*
  39  * POSIX pathconf information
  40  *
  41  * static pathconf kludge notes:
  42  *      For NFSv2 servers, we've added a vop (vop_cntl) to dig out pathconf
  43  *      information.  The mount program asked for the information from
  44  *      a remote mountd daemon.  If it gets it, it passes the info
  45  *      down in a new args field.  The info is passed in the struct below
  46  *      in nfsargs.pathconf.  There's a new NFS mount flag so that you know
  47  *      this is happening.  NFS stores the information locally; when a
  48  *      pathconf request is made, the request is intercepted at the client
  49  *      and the information is retrieved from the struct passed down by
  50  *      mount. It's a kludge that will go away as soon
  51  *      as we can ask the nfs protocol these sorts of questions (NFSr3).
  52  *      All code is noted by "static pathconf kludge" comments and is
  53  *      restricted to nfs code in the kernel.
  54  */
  55
  56 #define _BITS           (8 * sizeof (short))
  57 #define _PC_N           ((_PC_LAST + _BITS - 1) / _BITS)
  58 #define _PC_ISSET(n, a) (a[(n) / _BITS] & (1 << ((n) % _BITS)))
  59 #define _PC_SET(n, a)   (a[(n) / _BITS] |= (1 << ((n) % _BITS)))
  60 #define _PC_ERROR       0
  61
  62 struct  pathcnf {
  63         /*
  64          * pathconf() information
  65          */
  66         int             pc_link_max;    /* max links allowed */
  67         short           pc_max_canon;   /* max line len for a tty */
  68         short           pc_max_input;   /* input a tty can eat all once */
  69         short           pc_name_max;    /* max file name length (dir entry) */
  70         short           pc_path_max;    /* path name len (/x/y/z/...) */
  71         short           pc_pipe_buf;    /* size of a pipe (bytes) */
  72         uchar_t         pc_vdisable;    /* safe char to turn off c_cc[i] */
  73         char            pc_xxx;         /* alignment padding; cc_t == char */
  74         short           pc_mask[_PC_N]; /* see below */
  75 #ifdef  _KERNEL
  76         short           pc_refcnt;      /* number of mounts that use this */
  77         struct pathcnf  *pc_next;       /* linked list */
  78 #endif
  79 };
  80
  81 #ifdef _SYSCALL32
  82 struct  pathcnf32 {
  83         /*
  84          * pathconf() information
  85          */
  86         int32_t         pc_link_max;    /* max links allowed */
  87         int16_t         pc_max_canon;   /* max line len for a tty */
  88         int16_t         pc_max_input;   /* input a tty can eat all once */
  89         int16_t         pc_name_max;    /* max file name length (dir entry) */
  90         int16_t         pc_path_max;    /* path name len (/x/y/z/...) */
  91         int16_t         pc_pipe_buf;    /* size of a pipe (bytes) */
  92         uint8_t         pc_vdisable;    /* safe char to turn off c_cc[i] */
  93         int8_t          pc_xxx;         /* alignment padding; cc_t == char */
  94         int16_t         pc_mask[_PC_N]; /* see below */
  95 #ifdef  _KERNEL
  96         int16_t         pc_refcnt;      /* number of mounts that use this */
  97         caddr32_t       pc_next;        /* linked list */
  98 #endif
  99 };
 100 #endif /* _SYSCALL32 */
 101
 102 /*
 103  * pc_mask is used to encode either
 104  *      a) boolean values (for chown_restricted and no_trunc)
 105  *      b) errno on/off (for link, canon, input, name, path, and pipe)
 106  * The _PC_XXX values are defined in unistd.h; they start at 1 and go up
 107  * sequentially.
 108  * _PC_ERROR is used as the first bit to indicate total failure
 109  * (all info invalid).
 110  * To check for an error something like
 111  *      _PC_ISSET(_PC_PATHMAX, foo.pc_mask) != 0
 112  * is used.
 113  */
 114
 115 /*
 116  * The size of the non-kernel part of the struct.
 117  */
 118 #ifdef  _KERNEL
 119 #define PCSIZ           ((size_t)(&(((struct pathcnf *)0)->pc_refcnt)))
 120 #define PCCMP(p1, p2)   bcmp((char *)p1, (char *)p2, PCSIZ)
 121 #endif
 122
 123 #ifdef  __cplusplus
 124 }
 125 #endif
 126
 127 #endif  /* _SYS_PATHCONF_H */