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) 1996-2003, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        $PostgreSQL: pgsql/src/port/fseeko.c,v 1.14 2004/03/23 05:26:53 momjian Exp $
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16 /*
  17  * We have to use the native defines here because configure hasn't
  18  * completed yet.
  19  */
  20 #if defined(__bsdi__) || defined(__NetBSD__)
  21
  22 #include "c.h"
  23
  24 #ifdef bsdi
  25 #include <pthread.h>
  26 #endif
  27 #include <stdio.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <errno.h>
  31
  32 /*
  33  *      On BSD/OS and NetBSD, off_t and fpos_t are the same.  Standards
  34  *      say off_t is an arithmetic type, but not necessarily integral,
  35  *      while fpos_t might be neither.
  36  *
  37  *      This is thread-safe on BSD/OS using flockfile/funlockfile.
  38  */
  39
  40 int
  41 fseeko(FILE *stream, off_t offset, int whence)
  42 {
  43         off_t           floc;
  44         struct stat filestat;
  45
  46         switch (whence)
  47         {
  48                 case SEEK_CUR:
  49 #ifdef bsdi
  50                         flockfile(stream);
  51 #endif
  52                         if (fgetpos(stream, &floc) != 0)
  53                                 goto failure;
  54                         floc += offset;
  55                         if (fsetpos(stream, &floc) != 0)
  56                                 goto failure;
  57 #ifdef bsdi
  58                         funlockfile(stream);
  59 #endif
  60                         return 0;
  61                         break;
  62                 case SEEK_SET:
  63                         if (fsetpos(stream, &offset) != 0)
  64                                 return -1;
  65                         return 0;
  66                         break;
  67                 case SEEK_END:
  68 #ifdef bsdi
  69                         flockfile(stream);
  70 #endif
  71                         fflush(stream); /* force writes to fd for stat() */
  72                         if (fstat(fileno(stream), &filestat) != 0)
  73                                 goto failure;
  74                         floc = filestat.st_size;
  75                         if (fsetpos(stream, &floc) != 0)
  76                                 goto failure;
  77 #ifdef bsdi
  78                         funlockfile(stream);
  79 #endif
  80                         return 0;
  81                         break;
  82                 default:
  83                         errno = EINVAL;
  84                         return -1;
  85         }
  86
  87 failure:
  88 #ifdef bsdi
  89         funlockfile(stream);
  90 #endif
  91         return -1;
  92 }
  93
  94
  95 off_t
  96 ftello(FILE *stream)
  97 {
  98         off_t           floc;
  99
 100         if (fgetpos(stream, &floc) != 0)
 101                 return -1;
 102         return floc;
 103 }
 104
 105 #endif