sysdeps/unix/sysv/linux/mips/pread64.c

   1 /* Copyright (C) 1997, 1998, 2000, 2002, 2003, 2004
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   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 #ifndef NO_SGIDEFS_H
  23 #include <sgidefs.h>
  24 #endif
  25 #include <unistd.h>
  26 #include <endian.h>
  27
  28 #include <sysdep-cancel.h>
  29 #include <sys/syscall.h>
  30 #include <bp-checks.h>
  31
  32 #include <kernel-features.h>
  33
  34 #ifdef __NR_pread64             /* Newer kernels renamed but it's the same.  */
  35 # ifdef __NR_pread
  36 #  error "__NR_pread and __NR_pread64 both defined???"
  37 # endif
  38 # define __NR_pread __NR_pread64
  39 #endif
  40
  41 #if defined __NR_pread || __ASSUME_PREAD_SYSCALL > 0
  42
  43 # if __ASSUME_PREAD_SYSCALL == 0
  44 static ssize_t __emulate_pread64 (int fd, void *buf, size_t count,
  45                                   off64_t offset) internal_function;
  46 # endif
  47
  48 ssize_t
  49 __libc_pread64 (fd, buf, count, offset)
  50      int fd;
  51      void *buf;
  52      size_t count;
  53      off64_t offset;
  54 {
  55   ssize_t result;
  56
  57
  58   if (SINGLE_THREAD_P)
  59     {
  60      /* First try the syscall.  */
  61 #if _MIPS_SIM == _ABIN32 || _MIPS_SIM == _ABI64
  62       result = INLINE_SYSCALL (pread, 4, fd, CHECK_N (buf, count), count,
  63                                offset);
  64 #else
  65      result = INLINE_SYSCALL (pread, 6, fd, CHECK_N (buf, count), count, 0,
  66                               __LONG_LONG_PAIR ((off_t) (offset >> 32),
  67                               (off_t) (offset & 0xffffffff)));
  68 #endif
  69 # if __ASSUME_PREAD_SYSCALL == 0
  70      if (result == -1 && errno == ENOSYS)
  71      /* No system call available.  Use the emulation.  */
  72      result = __emulate_pread64 (fd, buf, count, offset);
  73 # endif
  74      return result;
  75     }
  76
  77   int oldtype = LIBC_CANCEL_ASYNC ();
  78
  79   /* First try the syscall.  */
  80 #if _MIPS_SIM == _ABIN32 || _MIPS_SIM == _ABI64
  81   result = INLINE_SYSCALL (pread, 4, fd, CHECK_N (buf, count), count, offset);
  82 #else
  83   result = INLINE_SYSCALL (pread, 6, fd, CHECK_N (buf, count), count, 0,
  84                            __LONG_LONG_PAIR ((off_t) (offset >> 32),
  85                                              (off_t) (offset & 0xffffffff)));
  86 #endif
  87 # if __ASSUME_PREAD_SYSCALL == 0
  88   if (result == -1 && errno == ENOSYS)
  89     /* No system call available.  Use the emulation.  */
  90     result = __emulate_pread64 (fd, buf, count, offset);
  91 # endif
  92
  93   LIBC_CANCEL_RESET (oldtype);
  94
  95   return result;
  96 }
  97
  98 weak_alias (__libc_pread64, __pread64)
  99 weak_alias (__libc_pread64, pread64)
 100
 101 # define __libc_pread64(fd, buf, count, offset) \
 102      static internal_function __emulate_pread64 (fd, buf, count, offset)
 103 #endif
 104
 105 #if __ASSUME_PREAD_SYSCALL == 0
 106 # include <sysdeps/posix/pread64.c>
 107 #endif