MP_TRACE_f(MP_FUNC, "retrieving bb: 0x%lx\n",
MP_TRACE_f(MP_FUNC, MP_FILTER_NAME_FORMAT "retrieving bb: 0x%lx\n", MP_FILTER_NAME(filter->f),
MP_INLINE apr_size_t modperl_input_filter_read(pTHX_                                               modperl_filter_t *filter,                                               SV *buffer,                                               apr_size_t wanted){    apr_size_t len = 0;    if (!filter->bb_in) {        /* This should be read only once per handler invocation! */        filter->bb_in = apr_brigade_create(filter->pool,                                           filter->f->c->bucket_alloc);        ap_get_brigade(filter->f->next, filter->bb_in,                       filter->input_mode, filter->block, filter->readbytes);        MP_TRACE_f(MP_FUNC, "retrieving bb: 0x%lx\n",                   (unsigned long)(filter->bb_in));    }    len = modperl_filter_read(aTHX_ filter, buffer, wanted);/*     if (APR_BRIGADE_EMPTY(filter->bb_in)) { *//*         apr_brigade_destroy(filter->bb_in); *//*         filter->bb_in = NULL; *//*     } */    if (filter->flush && len == 0) {        /* if len > 0 then $filter->write will flush */        modperl_input_filter_flush(filter);    }    return len;}