sysdeps/mach/hurd/xmknodat.c

   1 /* Create a device file relative to an open directory.  Hurd version.
   2    Copyright (C) 1991,1992,1993,1994,1995,1996,1999,2002,2005,2006
   3         Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library 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 GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <errno.h>
  22 #include <sys/stat.h>
  23 #include <hurd.h>
  24 #include <hurd/fd.h>
  25 #include <hurd/paths.h>
  26 #include <fcntl.h>
  27 #include "stdio-common/_itoa.h"
  28 #include <string.h>
  29 #include <sys/types.h>
  30
  31 /* Create a device file named PATH relative to FD, with permission and
  32    special bits MODE and device number DEV (which can be constructed
  33    from major and minor device numbers with the `makedev' macro
  34    above).  */
  35 int
  36 __xmknodat (int vers, int fd, const char *path, mode_t mode, dev_t *dev)
  37 {
  38   error_t err;
  39   file_t dir, node;
  40   char *name;
  41   char buf[100], *bp;
  42   const char *translator;
  43   size_t len;
  44
  45   if (vers != _MKNOD_VER)
  46     return __hurd_fail (EINVAL);
  47
  48   if (S_ISCHR (mode))
  49     {
  50       translator = _HURD_CHRDEV;
  51       len = sizeof (_HURD_CHRDEV);
  52     }
  53   else if (S_ISBLK (mode))
  54     {
  55       translator = _HURD_BLKDEV;
  56       len = sizeof (_HURD_BLKDEV);
  57     }
  58   else if (S_ISFIFO (mode))
  59     {
  60       translator = _HURD_FIFO;
  61       len = sizeof (_HURD_FIFO);
  62     }
  63   else if (S_ISREG (mode))
  64     {
  65       translator = NULL;
  66       len = 0;
  67     }
  68   else
  69     {
  70       errno = EINVAL;
  71       return -1;
  72     }
  73
  74   if (translator != NULL && ! S_ISFIFO (mode))
  75     {
  76       /* We set the translator to "ifmt\0major\0minor\0", where IFMT
  77          depends on the S_IFMT bits of our MODE argument, and MAJOR and
  78          MINOR are ASCII decimal (octal or hex would do as well)
  79          representations of our arguments.  Thus the convention is that
  80          CHRDEV and BLKDEV translators are invoked with two non-switch
  81          arguments, giving the major and minor device numbers in %i format. */
  82
  83       bp = buf + sizeof (buf);
  84       *--bp = '\0';
  85       bp = _itoa (minor (*dev), bp, 10, 0);
  86       *--bp = '\0';
  87       bp = _itoa (major (*dev), bp, 10, 0);
  88       memcpy (bp - len, translator, len);
  89       translator = bp - len;
  90       len = buf + sizeof (buf) - translator;
  91     }
  92
  93   dir = __file_name_split_at (fd, path, &name);
  94   if (dir == MACH_PORT_NULL)
  95     return -1;
  96
  97   /* Create a new, unlinked node in the target directory.  */
  98   err = __dir_mkfile (dir, O_WRITE, (mode & ~S_IFMT) & ~_hurd_umask, &node);
  99
 100   if (! err && translator != NULL)
 101     /* Set the node's translator to make it a device.  */
 102     err = __file_set_translator (node,
 103                                  FS_TRANS_EXCL | FS_TRANS_SET,
 104                                  FS_TRANS_EXCL | FS_TRANS_SET, 0,
 105                                  translator, len,
 106                                  MACH_PORT_NULL, MACH_MSG_TYPE_COPY_SEND);
 107
 108   if (! err)
 109     /* Link the node, now a valid device, into the target directory.  */
 110     err = __dir_link (dir, node, name, 1);
 111
 112   __mach_port_deallocate (__mach_task_self (), dir);
 113   __mach_port_deallocate (__mach_task_self (), node);
 114
 115   if (err)
 116     return __hurd_fail (err);
 117   return 0;
 118 }