mod_proxy_ftp.c

        /* read the body, pass it to the output filters */
        while (ap_get_brigade(data->input_filters,
                              bb,
                              AP_MODE_READBYTES,
                              APR_BLOCK_READ,
                              conf->io_buffer_size) == APR_SUCCESS) {
#if DEBUGGING
            {
                apr_off_t readbytes;
                apr_brigade_length(bb, 0, &readbytes);
                ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, APLOGNO(01056)
                             "proxy: readbytes: %#x", readbytes);
            }
#endif
            /* sanity check */
            if (APR_BRIGADE_EMPTY(bb)) {
                break;
            }

            /* found the last brigade? */
            if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) {
                /* if this is the last brigade, cleanup the
                 * backend connection first to prevent the
                 * backend server from hanging around waiting
                 * for a slow client to eat these bytes
                 */
                ap_flush_conn(data);
                if (data_sock) {
                    apr_socket_close(data_sock);
                }
                data_sock = NULL;
                ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01057)
                              "data connection closed");
                /* signal that we must leave */
                finish = TRUE;
            }

            /* if no EOS yet, then we must flush */
            if (FALSE == finish) {
                e = apr_bucket_flush_create(c->bucket_alloc);
                APR_BRIGADE_INSERT_TAIL(bb, e);
            }

            /* try send what we read */
            if (ap_pass_brigade(r->output_filters, bb) != APR_SUCCESS
                || c->aborted) {
                /* Ack! Phbtt! Die! User aborted! */
                finish = TRUE;
            }

            /* make sure we always clean up after ourselves */
            apr_brigade_cleanup(bb);

            /* if we are done, leave */
            if (TRUE == finish) {
                break;
            }
        }
        ap_log_rerror(APLOG_MARK, APLOG_TRACE3, 0, r, "end body send");

    }
    if (data_sock) {
        ap_flush_conn(data);
        apr_socket_close(data_sock);
        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01058) "data connection closed");
    }

    /* Retrieve the final response for the RETR or LIST commands */
    proxy_ftp_command(NULL, r, origin, bb, &ftpmessage);
    apr_brigade_cleanup(bb);

    /*
     * VII: Clean Up -------------
     *
     * If there are no KeepAlives, or if the connection has been signalled to
     * close, close the socket and clean up
     */

    /* finish */
    proxy_ftp_command("QUIT" CRLF, r, origin, bb, &ftpmessage);
    /* responses: 221, 500 */
    /* 221 Service closing control connection. */
    /* 500 Syntax error, command unrecognized. */
    ap_flush_conn(origin);
    proxy_ftp_cleanup(r, backend);

    apr_brigade_destroy(bb);
    return OK;
}

static void ap_proxy_ftp_register_hook(apr_pool_t *p)
{
    /* hooks */
    proxy_hook_scheme_handler(proxy_ftp_handler, NULL, NULL, APR_HOOK_MIDDLE);
    proxy_hook_canon_handler(proxy_ftp_canon, NULL, NULL, APR_HOOK_MIDDLE);
    /* filters */
    ap_register_output_filter("PROXY_SEND_DIR", proxy_send_dir_filter,
                              NULL, AP_FTYPE_RESOURCE);
    /* Compile the output format of "ls -s1" as a fallback for non-unix ftp listings */
    ls_regex = ap_pregcomp(p, LS_REG_PATTERN, AP_REG_EXTENDED);
    ap_assert(ls_regex != NULL);
}

static const command_rec proxy_ftp_cmds[] =
{
    AP_INIT_FLAG("ProxyFtpListOnWildcard", set_ftp_list_on_wildcard, NULL,
     RSRC_CONF|ACCESS_CONF, "Whether wildcard characters in a path cause mod_proxy_ftp to list the files instead of trying to get them. Defaults to on."),
    AP_INIT_FLAG("ProxyFtpEscapeWildcards", set_ftp_escape_wildcards, NULL,
     RSRC_CONF|ACCESS_CONF, "Whether the proxy should escape wildcards in paths before sending them to the FTP server.  Defaults to on, but most FTP servers will need it turned off if you need to manage paths that contain wildcard characters."),
    AP_INIT_TAKE1("ProxyFtpDirCharset", set_ftp_directory_charset, NULL,
     RSRC_CONF|ACCESS_CONF, "Define the character set for proxied FTP listings"),
    {NULL}
};


AP_DECLARE_MODULE(proxy_ftp) = {
    STANDARD20_MODULE_STUFF,
    create_proxy_ftp_dir_config,/* create per-directory config structure */
    merge_proxy_ftp_dir_config, /* merge per-directory config structures */
    NULL,                       /* create per-server config structure */
    NULL,                       /* merge per-server config structures */
    proxy_ftp_cmds,             /* command apr_table_t */
    ap_proxy_ftp_register_hook  /* register hooks */
};