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, 2004 Free
   4    Software 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_dev_name__;
  21
  22 int rmt_open__ (const char *, int, int, const char *);
  23 int rmt_close__ (int);
  24 size_t rmt_read__ (int, char *, size_t);
  25 size_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(dev_name) \
  36   (!force_local_option && (rmt_dev_name__ = strchr (dev_name, ':')) \
  37    && rmt_dev_name__ > (dev_name) \
  38    && ! memchr (dev_name, '/', rmt_dev_name__ - (dev_name)))
  39
  40 #define _isrmt(fd) \
  41   ((fd) >= __REM_BIAS)
  42
  43 #define __REM_BIAS (1 << 30)
  44
  45 #ifndef O_CREAT
  46 # define O_CREAT 01000
  47 #endif
  48
  49 #define rmtopen(dev_name, oflag, mode, command) \
  50   (_remdev (dev_name) ? rmt_open__ (dev_name, oflag, __REM_BIAS, command) \
  51    : open (dev_name, oflag, mode))
  52
  53 #define rmtaccess(dev_name, amode) \
  54   (_remdev (dev_name) ? 0 : access (dev_name, amode))
  55
  56 #define rmtstat(dev_name, buffer) \
  57   (_remdev (dev_name) ? (errno = EOPNOTSUPP), -1 : stat (dev_name, buffer))
  58
  59 #define rmtcreat(dev_name, mode, command) \
  60    (_remdev (dev_name) \
  61     ? rmt_open__ (dev_name, 1 | O_CREAT, __REM_BIAS, command) \
  62     : creat (dev_name, mode))
  63
  64 #define rmtlstat(dev_name, muffer) \
  65   (_remdev (dev_name) ? (errno = EOPNOTSUPP), -1 : lstat (dev_name, buffer))
  66
  67 #define rmtread(fd, buffer, length) \
  68   (_isrmt (fd) ? rmt_read__ (fd - __REM_BIAS, buffer, length) \
  69    : safe_read (fd, buffer, length))
  70
  71 #define rmtwrite(fd, buffer, length) \
  72   (_isrmt (fd) ? rmt_write__ (fd - __REM_BIAS, buffer, length) \
  73    : full_write (fd, buffer, length))
  74
  75 #define rmtlseek(fd, offset, where) \
  76   (_isrmt (fd) ? rmt_lseek__ (fd - __REM_BIAS, offset, where) \
  77    : lseek (fd, offset, where))
  78
  79 #define rmtclose(fd) \
  80   (_isrmt (fd) ? rmt_close__ (fd - __REM_BIAS) : close (fd))
  81
  82 #define rmtioctl(fd, request, argument) \
  83   (_isrmt (fd) ? rmt_ioctl__ (fd - __REM_BIAS, request, argument) \
  84    : ioctl (fd, request, argument))
  85
  86 #define rmtdup(fd) \
  87   (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : dup (fd))
  88
  89 #define rmtfstat(fd, buffer) \
  90   (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : fstat (fd, buffer))
  91
  92 #define rmtfcntl(cd, command, argument) \
  93   (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : fcntl (fd, command, argument))
  94
  95 #define rmtisatty(fd) \
  96   (_isrmt (fd) ? 0 : isatty (fd))