db2/os/db_os_lseek.c

   1 /*-
   2  * See the file LICENSE for redistribution information.
   3  *
   4  * Copyright (c) 1997
   5  *      Sleepycat Software.  All rights reserved.
   6  */
   7
   8 #include "config.h"
   9
  10 #ifndef lint
  11 static const char sccsid[] = "@(#)db_os_lseek.c 10.3 (Sleepycat) 6/28/97";
  12 #endif /* not lint */
  13
  14 #ifndef NO_SYSTEM_INCLUDES
  15 #include <sys/types.h>
  16
  17 #include <errno.h>
  18 #include <unistd.h>
  19 #endif
  20
  21 #include "db_int.h"
  22 #include "os_ext.h"
  23
  24 /*
  25  * __db_lseek --
  26  *      Seek to a page/byte offset in the file.
  27  *
  28  * PUBLIC: int __db_lseek __P((int, size_t, db_pgno_t, u_long, int));
  29  */
  30 int
  31 __db_lseek(fd, pgsize, pageno, relative, whence)
  32         int fd;
  33         size_t pgsize;
  34         db_pgno_t pageno;
  35         u_long relative;
  36         int whence;
  37 {
  38         /* 64-bit offsets are done differently by different vendors. */
  39 #undef  __LSEEK_SET
  40 #ifdef  HAVE_LLSEEK
  41 #define __LSEEK_SET
  42         offset_t offset;                        /* Solaris. */
  43
  44         offset = pgsize * pageno + relative;
  45         return (llseek(fd, offset, whence) == -1 ? errno : 0);
  46 #endif
  47 #ifdef  HAVE_LSEEKI
  48 #define __LSEEK_SET
  49         __int64 offset;                         /* WNT */
  50
  51         offset = pgsize * pageno + relative;
  52         return (_lseeki64(fd, offset, whence) == -1 ? errno : 0);
  53 #endif
  54 #ifndef __LSEEK_SET
  55         off_t offset;                           /* Default. */
  56
  57         offset = pgsize * pageno + relative;
  58         return (lseek(fd, offset, whence) == -1 ? errno : 0);
  59 #endif
  60 }