Function ap_proxy_transfer_between_connections

modules/proxy/proxy_util.c:5234–5379

#define PROXY_TRANSFER_MAX_READS 10000

PROXY_DECLARE(apr_status_t) ap_proxy_transfer_between_connections(
                                                       request_rec *r,
                                                       conn_rec *c_i,
                                                       conn_rec *c_o,
                                                       apr_bucket_brigade *bb_i,
                                                       apr_bucket_brigade *bb_o,
                                                       const char *name,
                                                       int *sent,
                                                       apr_off_t bsize,
                                                       int flags)
{
    apr_status_t rv;
    int flush_each = 0;
    unsigned int num_reads = 0;
#ifdef DEBUGGING
    apr_off_t len;
#endif

    /*
     * Compat: since FLUSH_EACH is default (and zero) for legacy reasons, we
     * pretend it's no FLUSH_AFTER nor YIELD_PENDING flags, the latter because
     * flushing would defeat the purpose of checking for pending data (hence
     * determine whether or not the output chain/stack is full for stopping).
     */
    if (!(flags & (AP_PROXY_TRANSFER_FLUSH_AFTER |
                   AP_PROXY_TRANSFER_YIELD_PENDING))) {
        flush_each = 1;
    }

    for (;;) {
        apr_brigade_cleanup(bb_i);
        rv = ap_get_brigade(c_i->input_filters, bb_i, AP_MODE_READBYTES,
                            APR_NONBLOCK_READ, bsize);
        if (rv != APR_SUCCESS) {
            if (!APR_STATUS_IS_EAGAIN(rv) && !APR_STATUS_IS_EOF(rv)) {
                ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO(03308)
                              "ap_proxy_transfer_between_connections: "
                              "error on %s - ap_get_brigade",
                              name);
                if (rv == APR_INCOMPLETE) {
                    /* Don't return APR_INCOMPLETE, it'd mean "should yield"
                     * for the caller, while it means "incomplete body" here
                     * from ap_http_filter(), which is an error.
                     */
                    rv = APR_EGENERAL;
                }
            }
            break;
        }

        if (c_o->aborted) {
            apr_brigade_cleanup(bb_i);
            flags &= ~AP_PROXY_TRANSFER_FLUSH_AFTER;
            rv = APR_EPIPE;
            break;
        }
        if (APR_BRIGADE_EMPTY(bb_i)) {
            break;