sysdeps/unix/sysv/linux/powerpc/powerpc32/truncate64.c

   1 /* Copyright (C) 1997,1998,1999,2000,2002,2005,2006,2011
   2         Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <sys/types.h>
  20 #include <errno.h>
  21 #include <unistd.h>
  22
  23 #include <sysdep.h>
  24 #include <sys/syscall.h>
  25 #include <bp-checks.h>
  26
  27 #include <kernel-features.h>
  28
  29 #ifdef __NR_truncate64
  30 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  31 /* The variable is shared between all wrappers around *truncate64 calls.  */
  32 int __have_no_truncate64;
  33 #endif
  34
  35
  36 /* Truncate the file referenced by FD to LENGTH bytes.  */
  37 int
  38 truncate64 (path, length)
  39      const char *path;
  40      off64_t length;
  41 {
  42 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  43   if (! __have_no_truncate64)
  44 #endif
  45     {
  46 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  47       int saved_errno = errno;
  48 #endif
  49       /* On PPC32 64bit values are aligned in odd/even register pairs.  */
  50       int result = INLINE_SYSCALL (truncate64, 4, CHECK_STRING (path), 0,
  51                                    (long) (length >> 32),
  52                                    (long) length);
  53
  54 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  55       if (result != -1 || errno != ENOSYS)
  56 #endif
  57         return result;
  58
  59 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  60       __set_errno (saved_errno);
  61       __have_no_truncate64 = 1;
  62 #endif
  63     }
  64
  65 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  66   if ((off_t) length != length)
  67     {
  68       __set_errno (EINVAL);
  69       return -1;
  70     }
  71   return __truncate (path, (off_t) length);
  72 #endif
  73 }
  74
  75 #else
  76 /* Use the generic implementation.  */
  77 # include <misc/truncate64.c>
  78 #endif