sysdeps/unix/sysv/linux/powerpc/powerpc32/ftruncate64.c

   1 /* Copyright (C) 1997-2002,2005,2006,2011 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/types.h>
  19 #include <errno.h>
  20 #include <unistd.h>
  21
  22 #include <sysdep.h>
  23 #include <sys/syscall.h>
  24
  25 #include <kernel-features.h>
  26
  27 #ifdef __NR_ftruncate64
  28 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  29 /* The variable is shared between all wrappers around *truncate64 calls.  */
  30 extern int __have_no_truncate64;
  31 #endif
  32
  33
  34 /* Truncate the file referenced by FD to LENGTH bytes.  */
  35 int
  36 __ftruncate64 (fd, length)
  37      int fd;
  38      off64_t length;
  39 {
  40 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  41   if (! __have_no_truncate64)
  42 #endif
  43     {
  44 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  45       int saved_errno = errno;
  46 #endif
  47       /* On PPC32 64bit values are aligned in odd/even register pairs.  */
  48       int result = INLINE_SYSCALL (ftruncate64, 4, fd, 0,
  49                                    (long) (length >> 32),
  50                                    (long) length);
  51
  52 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  53       if (result != -1 || errno != ENOSYS)
  54 #endif
  55         return result;
  56
  57 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  58       __set_errno (saved_errno);
  59       __have_no_truncate64 = 1;
  60 #endif
  61     }
  62
  63 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  64   if ((off_t) length != length)
  65     {
  66       __set_errno (EINVAL);
  67       return -1;
  68     }
  69   return __ftruncate (fd, (off_t) length);
  70 #endif
  71 }
  72 weak_alias (__ftruncate64, ftruncate64)
  73
  74 #else
  75 /* Use the generic implementation.  */
  76 # include <misc/ftruncate64.c>
  77 #endif