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

   1 /* Copyright (C) 1997,1998,1999,2000,2002,2005,2006
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <sys/types.h>
  21 #include <errno.h>
  22 #include <unistd.h>
  23
  24 #include <sysdep.h>
  25 #include <sys/syscall.h>
  26 #include <bp-checks.h>
  27
  28 #include <kernel-features.h>
  29
  30 #ifdef __NR_truncate64
  31 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  32 /* The variable is shared between all wrappers around *truncate64 calls.  */
  33 int __have_no_truncate64;
  34 #endif
  35
  36
  37 /* Truncate the file FD refers to to LENGTH bytes.  */
  38 int
  39 truncate64 (path, length)
  40      const char *path;
  41      off64_t length;
  42 {
  43 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  44   if (! __have_no_truncate64)
  45 #endif
  46     {
  47 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  48       int saved_errno = errno;
  49 #endif
  50       /* On PPC32 64bit values are aligned in odd/even register pairs.  */
  51       int result = INLINE_SYSCALL (truncate64, 4, CHECK_STRING (path), 0,
  52                                    (long) (length >> 32),
  53                                    (long) length);
  54
  55 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  56       if (result != -1 || errno != ENOSYS)
  57 #endif
  58         return result;
  59
  60 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  61       __set_errno (saved_errno);
  62       __have_no_truncate64 = 1;
  63 #endif
  64     }
  65
  66 #ifndef __ASSUME_TRUNCATE64_SYSCALL
  67   if ((off_t) length != length)
  68     {
  69       __set_errno (EINVAL);
  70       return -1;
  71     }
  72   return __truncate (path, (off_t) length);
  73 #endif
  74 }
  75
  76 #else
  77 /* Use the generic implementation.  */
  78 # include <misc/truncate64.c>
  79 #endif