1  /* Definitions for communicating with a remote tape drive.
       2  
       3     Copyright (C) 1988, 1992, 1996-1997, 2001, 2003-2004, 2007, 2023 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 3, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
      19  
      20  extern char const *rmt_command;
      21  extern char const *rmt_dev_name__;
      22  
      23  int rmt_open__ (const char *, int, int, const char *);
      24  int rmt_close__ (int);
      25  size_t rmt_read__ (int, char *, size_t);
      26  size_t rmt_write__ (int, char *, size_t);
      27  off_t rmt_lseek__ (int, off_t, int);
      28  int rmt_ioctl__ (int, unsigned long int, void *);
      29  
      30  extern bool force_local_option;
      31  
      32  /* A filename is remote if it contains a colon not preceded by a slash,
      33     to take care of `/:/' which is a shorthand for `/.../<CELL-NAME>/fs'
      34     on machines running OSF's Distributing Computing Environment (DCE) and
      35     Distributed File System (DFS).  However, when --force-local, a
      36     filename is never remote.  */
      37  
      38  #define _remdev(dev_name) \
      39    (!force_local_option && (rmt_dev_name__ = strchr (dev_name, ':')) \
      40     && rmt_dev_name__ > (dev_name) \
      41     && ! memchr (dev_name, '/', rmt_dev_name__ - (dev_name)))
      42  
      43  #define _isrmt(fd) \
      44    ((fd) >= __REM_BIAS)
      45  
      46  #define __REM_BIAS (1 << 30)
      47  
      48  #ifndef O_CREAT
      49  # define O_CREAT 01000
      50  #endif
      51  
      52  #define rmtopen(dev_name, oflag, mode, command) \
      53    (_remdev (dev_name) ? rmt_open__ (dev_name, oflag, __REM_BIAS, command) \
      54     : open (dev_name, oflag, mode))
      55  
      56  #define rmtaccess(dev_name, amode) \
      57    (_remdev (dev_name) ? 0 : access (dev_name, amode))
      58  
      59  #define rmtstat(dev_name, buffer) \
      60    (_remdev (dev_name) ? (errno = EOPNOTSUPP), -1 : stat (dev_name, buffer))
      61  
      62  #define rmtcreat(dev_name, mode, command) \
      63     (_remdev (dev_name) \
      64      ? rmt_open__ (dev_name, O_CREAT | O_WRONLY, __REM_BIAS, command) \
      65      : creat (dev_name, mode))
      66  
      67  #define rmtlstat(dev_name, muffer) \
      68    (_remdev (dev_name) ? (errno = EOPNOTSUPP), -1 : lstat (dev_name, buffer))
      69  
      70  #define rmtread(fd, buffer, length) \
      71    (_isrmt (fd) ? rmt_read__ (fd - __REM_BIAS, buffer, length) \
      72     : safe_read (fd, buffer, length))
      73  
      74  #define rmtwrite(fd, buffer, length) \
      75    (_isrmt (fd) ? rmt_write__ (fd - __REM_BIAS, buffer, length) \
      76     : full_write (fd, buffer, length))
      77  
      78  #define rmtlseek(fd, offset, where) \
      79    (_isrmt (fd) ? rmt_lseek__ (fd - __REM_BIAS, offset, where) \
      80     : lseek (fd, offset, where))
      81  
      82  #define rmtclose(fd) \
      83    (_isrmt (fd) ? rmt_close__ (fd - __REM_BIAS) : close (fd))
      84  
      85  #define rmtioctl(fd, request, argument) \
      86    (_isrmt (fd) ? rmt_ioctl__ (fd - __REM_BIAS, request, argument) \
      87     : ioctl (fd, request, argument))
      88  
      89  #define rmtdup(fd) \
      90    (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : dup (fd))
      91  
      92  #define rmtfstat(fd, buffer) \
      93    (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : fstat (fd, buffer))
      94  
      95  #define rmtfcntl(cd, command, argument) \
      96    (_isrmt (fd) ? (errno = EOPNOTSUPP), -1 : fcntl (fd, command, argument))
      97  
      98  #define rmtisatty(fd) \
      99    (_isrmt (fd) ? 0 : isatty (fd))