Dogcows Code - chaz/tar/blob - src/rmt.h

   1 /* Definitions for communicating with a remote tape drive.
   2
   3    Copyright (C) 1988, 1992, 1996, 1997, 2001, 2003 Free Software
   4    Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 extern char *rmt_path__;
  21
  22 int rmt_open__ (const char *, int, int, const char *);
  23 int rmt_close__ (int);
  24 ssize_t rmt_read__ (int, char *, size_t);
  25 ssize_t rmt_write__ (int, char *, size_t);
  26 off_t rmt_lseek__ (int, off_t, int);
  27 int rmt_ioctl__ (int, int, char *);
  28
  29 /* A filename is remote if it contains a colon not preceded by a slash,
  30    to take care of `/:/' which is a shorthand for `/.../<CELL-NAME>/fs'
  31    on machines running OSF's Distributing Computing Environment (DCE) and
  32    Distributed File System (DFS).  However, when --force-local, a
  33    filename is never remote.  */
  34
  35 #define _remdev(Path) \
  36   (!force_local_option && (rmt_path__ = strchr (Path, ':')) \
  37    && rmt_path__ > (Path) && ! memchr (Path, rmt_path__ - (Path), '/'))
  38
  39 #define _isrmt(Fd) \
  40   ((Fd) >= __REM_BIAS)
  41
  42 #define __REM_BIAS (1 << 30)
  43
  44 #ifndef O_CREAT
  45 # define O_CREAT 01000
  46 #endif
  47
  48 #define rmtopen(Path, Oflag, Mode, Command) \
  49   (_remdev (Path) ? rmt_open__ (Path, Oflag, __REM_BIAS, Command) \
  50    : open (Path, Oflag, Mode))
  51
  52 #define rmtaccess(Path, Amode) \
  53   (_remdev (Path) ? 0 : access (Path, Amode))
  54
  55 #define rmtstat(Path, Buffer) \
  56   (_remdev (Path) ? (errno = EOPNOTSUPP), -1 : stat (Path, Buffer))
  57
  58 #define rmtcreat(Path, Mode, Command) \
  59    (_remdev (Path) \
  60     ? rmt_open__ (Path, 1 | O_CREAT, __REM_BIAS, Command) \
  61     : creat (Path, Mode))
  62
  63 #define rmtlstat(Path, Buffer) \
  64   (_remdev (Path) ? (errno = EOPNOTSUPP), -1 : lstat (Path, Buffer))
  65
  66 #define rmtread(Fd, Buffer, Length) \
  67   (_isrmt (Fd) ? rmt_read__ (Fd - __REM_BIAS, Buffer, Length) \
  68    : safe_read (Fd, Buffer, Length))
  69
  70 #define rmtwrite(Fd, Buffer, Length) \
  71   (_isrmt (Fd) ? rmt_write__ (Fd - __REM_BIAS, Buffer, Length) \
  72    : full_write (Fd, Buffer, Length))
  73
  74 #define rmtlseek(Fd, Offset, Where) \
  75   (_isrmt (Fd) ? rmt_lseek__ (Fd - __REM_BIAS, Offset, Where) \
  76    : lseek (Fd, Offset, Where))
  77
  78 #define rmtclose(Fd) \
  79   (_isrmt (Fd) ? rmt_close__ (Fd - __REM_BIAS) : close (Fd))
  80
  81 #define rmtioctl(Fd, Request, Argument) \
  82   (_isrmt (Fd) ? rmt_ioctl__ (Fd - __REM_BIAS, Request, Argument) \
  83    : ioctl (Fd, Request, Argument))
  84
  85 #define rmtdup(Fd) \
  86   (_isrmt (Fd) ? (errno = EOPNOTSUPP), -1 : dup (Fd))
  87
  88 #define rmtfstat(Fd, Buffer) \
  89   (_isrmt (Fd) ? (errno = EOPNOTSUPP), -1 : fstat (Fd, Buffer))
  90
  91 #define rmtfcntl(Fd, Command, Argument) \
  92   (_isrmt (Fd) ? (errno = EOPNOTSUPP), -1 : fcntl (Fd, Command, Argument))
  93
  94 #define rmtisatty(Fd) \
  95   (_isrmt (Fd) ? 0 : isatty (Fd))