Exim, при объеме письма больше 8192 время увеличивается координально. receive.c

static int
read_message_data_smtp(FILE *fout)
{
debug_printf("  function called \n");

int ch_state = 0;
register int ch;
register int linelength = 0;


while ((ch = (receive_getc)()) != EOF)
  {
  if (ch == 0) body_zerocount++;
  switch (ch_state)
    {
    case 0:                             /* After LF or CRLF */
    if (ch == '.')
      {
      ch_state = 3;
      continue;                         /* Don't ever write . after LF */
      }
    ch_state = 1;

    /* Else fall through to handle as normal uschar. */

    case 1:                             /* Normal state */
    if (ch == '\n')
      {
      ch_state = 0;
      body_linecount++;
      if (linelength > max_received_linelength)
        max_received_linelength = linelength;
      linelength = -1;
      }
    else if (ch == '\r')
      {
      ch_state = 2;
      continue;
      }
    break;

    case 2:                             /* After (unwritten) CR */
    body_linecount++;
    if (linelength > max_received_linelength)
      max_received_linelength = linelength;
    linelength = -1;
    if (ch == '\n')
      {
      ch_state = 0;
      }
    else
      {
      message_size++;
      if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
      if (ch != '\r') ch_state = 1; else continue;
      }
    break;

    case 3:                             /* After [CR] LF . */
    if (ch == '\n')
      return END_DOT;
    if (ch == '\r')
      {
      ch_state = 4;
      continue;
      }
    ch_state = 1;                       /* The dot itself is removed */
    break;

    case 4:                             /* After [CR] LF . CR */
    if (ch == '\n') return END_DOT;
    message_size++;
    body_linecount++;
    if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
    if (ch == '\r')
      {
      ch_state = 2;
      continue;
      }
    ch_state = 1;
    break;
    }

  /* Add the character to the spool file, unless skipping; then loop for the
  next. */

  message_size++;
  linelength++;
  if (fout != NULL)
    {
    if (fputc(ch, fout) == EOF) return END_WERROR;
    if (message_size > thismessage_size_limit) return END_SIZE;
    }
  }

/* Fall through here if EOF encountered. This indicates some kind of error,
since a correct message is terminated by [CR] LF . [CR] LF. */

return END_EOF;
}