granicus.if.org Git - postgresql/blob - src/port/fseeko.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * fseeko.c
   4  *        64-bit versions of fseeko/ftello()
   5  *
   6  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        src/port/fseeko.c
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16 /*
  17  * We have to use the native defines here because configure hasn't
  18  * completed yet.
  19  */
  20 #ifdef __NetBSD__
  21
  22 #include "c.h"
  23
  24 #include <sys/stat.h>
  25
  26
  27 /*
  28  *      On NetBSD, off_t and fpos_t are the same.  Standards
  29  *      say off_t is an arithmetic type, but not necessarily integral,
  30  *      while fpos_t might be neither.
  31  */
  32
  33 int
  34 fseeko(FILE *stream, off_t offset, int whence)
  35 {
  36         off_t           floc;
  37         struct stat filestat;
  38
  39         switch (whence)
  40         {
  41                 case SEEK_CUR:
  42                         if (fgetpos(stream, &floc) != 0)
  43                                 goto failure;
  44                         floc += offset;
  45                         if (fsetpos(stream, &floc) != 0)
  46                                 goto failure;
  47                         return 0;
  48                         break;
  49                 case SEEK_SET:
  50                         if (fsetpos(stream, &offset) != 0)
  51                                 return -1;
  52                         return 0;
  53                         break;
  54                 case SEEK_END:
  55                         fflush(stream);         /* force writes to fd for stat() */
  56                         if (fstat(fileno(stream), &filestat) != 0)
  57                                 goto failure;
  58                         floc = filestat.st_size;
  59                         floc += offset;
  60                         if (fsetpos(stream, &floc) != 0)
  61                                 goto failure;
  62                         return 0;
  63                         break;
  64                 default:
  65                         errno = EINVAL;
  66                         return -1;
  67         }
  68
  69 failure:
  70         return -1;
  71 }
  72
  73
  74 off_t
  75 ftello(FILE *stream)
  76 {
  77         off_t           floc;
  78
  79         if (fgetpos(stream, &floc) != 0)
  80                 return -1;
  81         return floc;
  82 }
  83
  84 #endif