cde/programs/dtksh/ksh93/src/lib/libast/sfio/sfsize.c

   1 /* $XConsortium: sfsize.c /main/3 1995/11/01 18:36:22 rswiston $ */
   2 /***************************************************************
   3 *                                                              *
   4 *                      AT&T - PROPRIETARY                      *
   5 *                                                              *
   6 *         THIS IS PROPRIETARY SOURCE CODE LICENSED BY          *
   7 *                          AT&T CORP.                          *
   8 *                                                              *
   9 *                Copyright (c) 1995 AT&T Corp.                 *
  10 *                     All Rights Reserved                      *
  11 *                                                              *
  12 *           This software is licensed by AT&T Corp.            *
  13 *       under the terms and conditions of the license in       *
  14 *       http://www.research.att.com/orgs/ssr/book/reuse        *
  15 *                                                              *
  16 *               This software was created by the               *
  17 *           Software Engineering Research Department           *
  18 *                    AT&T Bell Laboratories                    *
  19 *                                                              *
  20 *               For further information contact                *
  21 *                     gsf@research.att.com                     *
  22 *                                                              *
  23 ***************************************************************/
  24 #include        "sfhdr.h"
  25
  26 /*      Get the size of a stream.
  27 **
  28 **      Written by Kiem-Phong Vo (02/12/91)
  29 */
  30 #if __STD_C
  31 long sfsize(reg Sfio_t *f)
  32 #else
  33 long sfsize(f)
  34 reg Sfio_t      *f;
  35 #endif
  36 {
  37         reg int mode;
  38
  39         if((mode = f->mode&SF_RDWR) != f->mode && _sfmode(f,mode,0) < 0)
  40                 return -1L;
  41
  42         if(f->flags&SF_STRING)
  43         {       SFSTRSIZE(f);
  44                 return f->extent;
  45         }
  46
  47         if(f->extent >= 0 && (f->flags&(SF_SHARE|SF_APPEND)) )
  48         {       reg Sfdisc_t*   disc;
  49                 for(disc = f->disc; disc; disc = disc->disc)
  50                         if(disc->seekf)
  51                                 break;
  52                 if(disc)
  53                 {       f->extent = SFSK(f,0L,2,disc);
  54                         (void)SFSK(f,f->here,0,disc);
  55                 }
  56                 else
  57                 {       struct stat     st;
  58                         if(fstat(f->file,&st) < 0)
  59                                 f->extent = -1L;
  60                         else    f->extent = st.st_size;
  61                 }
  62         }
  63
  64         if(f->extent < 0)
  65                 return -1L;
  66         else if(f->mode&SF_READ)
  67                 return f->extent;
  68         else if(f->flags&SF_APPEND)
  69                 return f->extent + (f->next - f->data);
  70         else
  71         {       reg long s;
  72                 if((f->flags&(SF_SHARE|SF_PUBLIC)) == (SF_SHARE|SF_PUBLIC))
  73                 {       if((s = SFSK(f,0L,1,f->disc)) < 0)
  74                                 return -1L;
  75                         f->here = s;
  76                 }
  77                 s = f->here + (f->next - f->data);
  78                 return s >= f->extent ? s : f->extent;
  79         }
  80 }