/* fread.c (emx+gcc) -- Copyright (c) 1990-1993 by Eberhard Mattes */

#include <sys/emx.h>
#include <stdio.h>
#include <string.h>
#include <io.h>
#include <errno.h>

#define min(a,b) (((a) < (b)) ? (a) : (b))

size_t fread (void *buffer, size_t size, size_t count, FILE *stream)
{
  size_t total, left, n;
  int r;   /* signed! */
  char *dst;
  int fh, c;

  if (size == 0 || count == 0)
    return (0);
  total = size * count;
  if (total / count != size)
    {
      errno = ERANGE;
      return (0);
    }
  if (nbuf (stream))
    _fbuf (stream);
  left = total;
  dst = buffer;
  fh = fileno (stream);
  stream->flags |= _IOREAD;
  if (bbuf (stream))
    while (left != 0)
      {
        if (stream->rcount != 0)
          {
            n = min ((size_t)stream->rcount, left);
            memcpy (dst, stream->ptr, n);
            stream->ptr += n;
            stream->rcount -= n;
            dst += n;
            left -= n;
          }
        else if (left > BUFSIZ)
          {
            n = (left / BUFSIZ) * BUFSIZ;      /* Number of buffers */
            r = read (fh, dst, n);
            if (r < 0)
              {
                stream->flags |= _IOERR;
                break;
              }
            if (r == 0)
              {
                stream->flags |= _IOEOF;
                break;
              }
            left -= r;
            dst += r;
          }
        else
          {
            c = _fill (stream);
            if (c == EOF)
              break;
            *dst++ = (char)c;
            --left;
          }
      }
  else
    {
      if (stream->rcount != 0)
        {
          n = min ((size_t)stream->rcount, left);
          memcpy (dst, stream->ptr, n);
          stream->ptr += n;
          stream->rcount -= n;
          dst += n;
          left -= n;
        }
      while (left != 0)
        {
          r = read (fh, dst, left);
          if (r < 0)
            {
              stream->flags |= _IOERR;
              break;
            }
          if (r == 0)
            {
              stream->flags |= _IOEOF;
              break;
            }
          dst += r;
          left -= r;
        }
    }
  return ((total - left) / size);
}