date and time created 80/10/30 00:33:36 by mckusick

[unix-history] / usr / src / usr.bin / pascal / libpc / IOSYNC.c

/* Copyright (c) 1979 Regents of the University of California */

static char sccsid[] = "@(#)IOSYNC.c 1.1 %G%";

#include "h00vars.h"
#include "h01errs.h"

/*
* insure that a usable image is in the buffer window
*/
IOSYNC(curfile)

       register struct iorec   *curfile;
{
       register short          unit = curfile->funit;
       char                    *limit, *ptr;

       if (unit & FWRITE) {
               ERROR(EREADIT, curfile->pfname);
               return;
       }
       if ((unit & SYNC) == 0) {
               return;
       }
       if (unit & EOFF) {
               ERROR(EPASTEOF, curfile->pfname);
               return;
       }
       unit &= ~SYNC;
       fread(curfile->fileptr, curfile->fsize, 1, curfile->fbuf);
       if (ferror(curfile->fbuf)) {
               ERROR(EPASTEOF, curfile->pfname);
               return;
       }
       if (feof(curfile->fbuf)) {
               curfile->funit = unit | EOFF;
               limit = &curfile->fileptr[curfile->fsize];
               for (ptr = curfile->fileptr; ptr < limit; )
                       *ptr++ = 0;
               return;
       }
       if (unit & FTEXT) {
               if (*curfile->fileptr == '\n') {
                       unit |= EOLN;
                       *curfile->fileptr = ' ';
               } else {
                       unit &= ~EOLN;
               }
       }
       curfile->funit = unit;
}