Commit 6d99392a authored by William A. Rowe Jr's avatar William A. Rowe Jr
Browse files 

  Backport the body pre-fetch code from trunk/, modifying the three
  stream_te / stream_cl / spool_cl functions to presume an input_brigade
  before fighting with fetching additional body content.

  We will be using the bytes_read in a later commit to make a better
  decision about choosing to send a C-L or chunked body to the backend.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/proxy-reqbody-2.0.x@230724 13f79535-47bb-0310-9956-ffa450edef68
parent e20006d2

modules/proxy/proxy_http.c

+81 −45
Original line number Diff line number Diff line
@@ -469,28 +469,13 @@ static apr_status_t stream_reqbody_chunked(apr_pool_t *p, 
    add_te_chunked(p, bucket_alloc, header_brigade);

    terminate_headers(bucket_alloc, header_brigade);



    do {

    while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))

    {

        char chunk_hdr[20];  /* must be here due to transient bucket. */



        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }



        /* If this brigade contains EOS, either stop or remove it. */

        if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {

            seen_eos = 1;



            /* As a shortcut, if this brigade is simply an EOS bucket,

             * don't send anything down the filter chain.

             */

            if (APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade))) {

                break;

            }



            /* We can't pass this EOS to the output_filters. */

            e = APR_BRIGADE_LAST(input_brigade);

            apr_bucket_delete(e);
@@ -529,7 +514,19 @@ static apr_status_t stream_reqbody_chunked(apr_pool_t *p, 
        if (status != APR_SUCCESS) {

            return status;

        }

    } while (!seen_eos);



        if (seen_eos) {

            break;

        }



        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }

    }



    if (header_brigade) {

        /* we never sent the header brigade because there was no request body;
@@ -580,15 +577,8 @@ static apr_status_t stream_reqbody_cl(apr_pool_t *p, 
    }

    terminate_headers(bucket_alloc, header_brigade);



    do {

        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }



    while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))

    {

        apr_brigade_length(input_brigade, 1, &bytes);

        bytes_streamed += bytes;
@@ -636,7 +626,19 @@ static apr_status_t stream_reqbody_cl(apr_pool_t *p, 
        if (status != APR_SUCCESS) {

            return status;

        }

    } while (!seen_eos);



        if (seen_eos) {

            break;

        }



        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }

    }



    if (bytes_streamed != cl_val) {

        ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
@@ -679,26 +681,12 @@ static apr_status_t spool_reqbody_cl(apr_pool_t *p, 


    body_brigade = apr_brigade_create(p, bucket_alloc);



    do {

        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }



    while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))

    {

        /* If this brigade contains EOS, either stop or remove it. */

        if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {

            seen_eos = 1;



            /* As a shortcut, if this brigade is simply an EOS bucket,

             * don't send anything down the filter chain.

             */

            if (APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade))) {

                break;

            }



            /* We can't pass this EOS to the output_filters. */

            e = APR_BRIGADE_LAST(input_brigade);

            apr_bucket_delete(e);
@@ -759,7 +747,18 @@ static apr_status_t spool_reqbody_cl(apr_pool_t *p, 
        

        bytes_spooled += bytes;



    } while (!seen_eos);

        if (seen_eos) {

            break;

        }



        status = ap_get_brigade(r->input_filters, input_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                HUGE_STRING_LEN);



        if (status != APR_SUCCESS) {

            return status;

        }

    }



    if (bytes_spooled || force_cl) {

        add_cl(p, bucket_alloc, header_brigade, apr_off_t_toa(p, bytes_spooled));
@@ -804,6 +803,7 @@ apr_status_t ap_proxy_http_request(apr_pool_t *p, request_rec *r, 
    conn_rec *c = r->connection;

    apr_bucket_alloc_t *bucket_alloc = c->bucket_alloc;

    apr_bucket_brigade *input_brigade;

    apr_bucket_brigade *temp_brigade;

    char *buf;

    apr_bucket *e;

    const apr_array_header_t *headers_in_array;
@@ -814,6 +814,8 @@ apr_status_t ap_proxy_http_request(apr_pool_t *p, request_rec *r, 
    enum rb_methods rb_method = RB_INIT;

    const char *old_cl_val = NULL;

    const char *old_te_val = NULL;

    apr_off_t bytes_read = 0;

    apr_off_t bytes;

    int cl_zero; /* client sent "Content-Length: 0", which we forward on to server */

    int force10;
@@ -1031,6 +1033,40 @@ apr_status_t ap_proxy_http_request(apr_pool_t *p, request_rec *r, 
        }

    }



    /* Prefetch MAX_MEM_SPOOL bytes

     *

     * This helps us avoid any election of C-L v.s. T-E

     * request bodies, since we are willing to keep in

     * memory this much data, in any case.  This gives

     * us an instant C-L election if the body is of some

     * reasonable size.

     */

    temp_brigade = apr_brigade_create(p, bucket_alloc);

    do {

        status = ap_get_brigade(r->input_filters, temp_brigade,

                                AP_MODE_READBYTES, APR_BLOCK_READ,

                                MAX_MEM_SPOOL - bytes_read);

        if (status != APR_SUCCESS) {

            ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,

                         "proxy: prefetch request body failed to %s"

                         " from %s (%s)",

                         p_conn->name ? p_conn->name: "",

                         c->remote_ip, c->remote_host ? c->remote_host: "");

            return status;

        }



        apr_brigade_length(temp_brigade, 1, &bytes);

        APR_BRIGADE_CONCAT(input_brigade, temp_brigade);

        bytes_read += bytes;



    /* Ensure we don't hit a wall where we have a buffer too small

     * for ap_get_brigade's filters to fetch us another bucket,

     * surrender once we hit 80 bytes less than MAX_MEM_SPOOL

     * (an arbitrary value.)

     */

    } while ((bytes_read < MAX_MEM_SPOOL - 80) 

              && !APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade)));



    /* send CL or use chunked encoding?

     *

     * . CL is the most friendly to the origin server since it is the