toolchain/gcc/newlib/libc/reent/lseek64r.c

   1 /* Reentrant versions of lseek system call. */
   2
   3 #include <reent.h>
   4 #include <unistd.h>
   5 #include <_syslist.h>
   6
   7 /* Some targets provides their own versions of this functions.  Those
   8    targets should define REENTRANT_SYSCALLS_PROVIDED in TARGET_CFLAGS.  */
   9
  10 #ifdef __LARGE64_FILES
  11
  12 #ifdef _REENT_ONLY
  13 #ifndef REENTRANT_SYSCALLS_PROVIDED
  14 #define REENTRANT_SYSCALLS_PROVIDED
  15 #endif
  16 #endif
  17
  18 #ifndef REENTRANT_SYSCALLS_PROVIDED
  19
  20 /* We use the errno variable used by the system dependent layer.  */
  21 #undef errno
  22 extern int errno;
  23
  24 /*
  25 FUNCTION
  26         <<_lseek64_r>>---Reentrant version of lseek
  27
  28 INDEX
  29         _lseek64_r
  30
  31 ANSI_SYNOPSIS
  32         #include <reent.h>
  33         off64_t _lseek64_r(struct _reent *<[ptr]>,
  34                            int <[fd]>, off64_t <[pos]>, int <[whence]>);
  35
  36 TRAD_SYNOPSIS
  37         #include <reent.h>
  38         off64_t _lseek64_r(<[ptr]>, <[fd]>, <[pos]>, <[whence]>)
  39         struct _reent *<[ptr]>;
  40         int <[fd]>;
  41         off64_t <[pos]>;
  42         int <[whence]>;
  43
  44 DESCRIPTION
  45         This is a reentrant version of <<lseek64>>.  It
  46         takes a pointer to the global data block, which holds
  47         <<errno>>.  This function only exists on a system
  48         with large file support.
  49 */
  50
  51 _off64_t
  52 _DEFUN (_lseek64_r, (ptr, fd, pos, whence),
  53      struct _reent *ptr _AND
  54      int fd _AND
  55      _off64_t pos _AND
  56      int whence)
  57 {
  58   _off64_t ret;
  59
  60   errno = 0;
  61   if ((ret = _lseek64 (fd, pos, whence)) == (_off64_t) -1 && errno != 0)
  62     ptr->_errno = errno;
  63   return ret;
  64 }
  65
  66 #endif /* ! defined (REENTRANT_SYSCALLS_PROVIDED) */
  67
  68 #endif /* __LARGE64_FILES */