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/***********************************************************************/
/* */
/* Objective Caml */
/* */
/* Xavier Leroy, projet Cristal, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. All rights reserved. This file is distributed */
/* under the terms of the GNU Library General Public License, with */
/* the special exception on linking described in file ../../LICENSE. */
/* */
/***********************************************************************/
/* $Id$ */
#include <mlvalues.h>
#include <alloc.h>
#include "unixsupport.h"
#ifdef HAS_UNISTD
#include <unistd.h>
#else
#define SEEK_SET 0
#define SEEK_CUR 1
#define SEEK_END 2
#endif
static int seek_command_table[] = {
FILE_BEGIN, FILE_CURRENT, FILE_END
};
#ifndef INVALID_SET_FILE_POINTER
#define INVALID_SET_FILE_POINTER (-1)
#endif
CAMLprim value unix_lseek(value fd, value ofs, value cmd)
{
long ret;
long ofs_low = Long_val(ofs);
long ofs_high = ofs_low >= 0 ? 0 : -1;
long err;
ret = SetFilePointer(Handle_val(fd), ofs_low, &ofs_high,
seek_command_table[Int_val(cmd)]);
if (ret == INVALID_SET_FILE_POINTER) {
err = GetLastError();
if (err != NO_ERROR) {
win32_maperr(err);
uerror("lseek", Nothing);
}
}
if (ofs_high != 0 || ret > Max_long) {
win32_maperr(ERROR_ARITHMETIC_OVERFLOW);
uerror("lseek", Nothing);
}
return Val_long(ret);
}
CAMLprim value unix_lseek_64(value fd, value ofs, value cmd)
{
long ret;
long ofs_low = (long) Int64_val(ofs);
long ofs_high = (long) (Int64_val(ofs) >> 32);
long err;
ret = SetFilePointer(Handle_val(fd), ofs_low, &ofs_high,
seek_command_table[Int_val(cmd)]);
if (ret == INVALID_SET_FILE_POINTER) {
err = GetLastError();
if (err != NO_ERROR) {
win32_maperr(err);
uerror("lseek", Nothing);
}
}
return copy_int64((int64) ofs_high << 32 | ret);
}
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