Commit c7730616 authored by Ryan Bloom's avatar Ryan Bloom
Browse files

Modify the content-length filter to change the criteria used to determine 

if/when we compute the content-length.  There are just a few cases now:

        1) We already have all the data
        2) We don't have all the data and:
                2a)  This is a 1.1 request but we can't chunk
                2b)  The is a keep-alive request
	    In the future, we probably want to modify this to not
	    be a keep-alive request.

This filter always buffers 9K of data.  The reason is simple, the core will
buffer 9K at a time anyway, and there is a chance that we may get the end
of the request before we hit 9K.  This increases our chances of being able
to send a c-l.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@87055 13f79535-47bb-0310-9956-ffa450edef68
parent 14e329df

include/http_core.h

+4 −0
Original line number Diff line number Diff line
@@ -121,6 +121,10 @@ extern "C" { 
#define SATISFY_ANY 1

#define SATISFY_NOSPEC 2



/* Make sure we don't write less than 4096 bytes at any one time.

 */

#define AP_MIN_BYTES_TO_WRITE  9000



/**

 * Retrieve the value of Options for this request

 * @param r The current request

modules/http/http_core.c

+4 −8
Original line number Diff line number Diff line
@@ -89,10 +89,6 @@ 
#include <strings.h>

#endif



/* Make sure we don't write less than 4096 bytes at any one time.

 */

#define MIN_BYTES_TO_WRITE  9000



/* LimitXMLRequestBody handling */

#define AP_LIMIT_UNSET                  ((long) -1)

#define AP_DEFAULT_LIMIT_XML_BODY       ((size_t)1000000)
@@ -3063,7 +3059,7 @@ static apr_status_t coalesce_filter(ap_filter_t *f, ap_bucket_brigade *b) 


    if (ctx == NULL) {

        f->ctx = ctx = apr_pcalloc(p, sizeof(coalesce_filter_ctx_t));

        ctx->avail = MIN_BYTES_TO_WRITE;

        ctx->avail = AP_MIN_BYTES_TO_WRITE;

    }



    if (ctx->cnt) {
@@ -3093,7 +3089,7 @@ static apr_status_t coalesce_filter(ap_filter_t *f, ap_bucket_brigade *b) 
            if ((n < MIN_BUCKET_SIZE) && (n < ctx->avail)) {

                /* Coalesce this bucket into the buffer */

                if (ctx->buf == NULL) {

                    ctx->buf = apr_palloc(p, MIN_BYTES_TO_WRITE);

                    ctx->buf = apr_palloc(p, AP_MIN_BYTES_TO_WRITE);

                    ctx->cur = ctx->buf;

                    ctx->cnt = 0;

                }
@@ -3156,7 +3152,7 @@ static apr_status_t coalesce_filter(ap_filter_t *f, ap_bucket_brigade *b) 
        if (ctx) {

            ctx->cur = ctx->buf;

            ctx->cnt = 0;

            ctx->avail = MIN_BYTES_TO_WRITE;

            ctx->avail = AP_MIN_BYTES_TO_WRITE;

        }

    }

    else {
@@ -3390,7 +3386,7 @@ static apr_status_t core_output_filter(ap_filter_t *f, ap_bucket_brigade *b) 
        /* Completed iterating over the brigades, now determine if we want to

         * buffer the brigade or send the brigade out on the network

         */

        if ((!fd && (!more) && (nbytes < MIN_BYTES_TO_WRITE) && !AP_BUCKET_IS_FLUSH(e))

        if ((!fd && (!more) && (nbytes < AP_MIN_BYTES_TO_WRITE) && !AP_BUCKET_IS_FLUSH(e))

            || (AP_BUCKET_IS_EOS(e) && c->keepalive)) {

            

            /* NEVER save an EOS in here.  If we are saving a brigade with an

modules/http/http_protocol.c

+33 −32
Original line number Diff line number Diff line
@@ -2239,7 +2239,7 @@ AP_DECLARE(void) ap_send_http_header(request_rec *r) 


struct content_length_ctx {

    ap_bucket_brigade *saved;

    int hold_data;    /* Whether or not to buffer the data. */

    int compute_len;

};



/* This filter computes the content length, but it also computes the number
@@ -2258,32 +2258,6 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_content_length_filter(ap_filter_t *f, 
    ctx = f->ctx;

    if (!ctx) { /* first time through */

        f->ctx = ctx = apr_pcalloc(r->pool, sizeof(struct content_length_ctx));



        /* We won't compute a content length if one of the following is true:

         * . subrequest

         * . HTTP/0.9

         * . status HTTP_NOT_MODIFIED or HTTP_NO_CONTENT

         * . HEAD

         * . content length already computed

         * . can be chunked

         * . body already chunked

         * Much of this should correspond to checks in ap_set_keepalive().

         */

        if ((r->assbackwards 

            || r->status == HTTP_NOT_MODIFIED 

            || r->status == HTTP_NO_CONTENT

            || r->header_only

            || r->proto_num == HTTP_VERSION(1,1)

            || ap_find_last_token(f->r->pool,

                                  apr_table_get(r->headers_out,

                                                "Transfer-Encoding"),

                                                "chunked"))

            && (!AP_BUCKET_IS_EOS(AP_BRIGADE_LAST(b)))) {

            ctx->hold_data = 0;

        }

        else {

            ctx->hold_data = 1;

        }

    }



    AP_BRIGADE_FOREACH(e, b) {
@@ -2305,7 +2279,34 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_content_length_filter(ap_filter_t *f, 
        r->bytes_sent += length;

    }



    if (ctx->hold_data) { /* calculating content length? */

    if (r->bytes_sent < AP_MIN_BYTES_TO_WRITE) {

        ap_save_brigade(f, &ctx->saved, &b);

        return APR_SUCCESS;

    }



    /* We will compute a content length if:

     *     We already have all the data

     *         This is a bit confusing, because we will always buffer up

     *         to AP_MIN_BYTES_TO_WRITE, so if we get all the data while

     *         we are buffering that much data, we set the c-l.

     *  or We are in a 1.1 request and we can't chunk

     *  or This is a keepalive connection

     *         We may want to change this later to just close the connection

     */

    if ((r->proto_num == HTTP_VERSION(1,1)

        && !ap_find_last_token(f->r->pool,

                              apr_table_get(r->headers_out,

                                            "Transfer-Encoding"),

                                            "chunked"))

        || (f->r->connection->keepalive)

        || (AP_BUCKET_IS_EOS(AP_BRIGADE_LAST(b)))) {

        ctx->compute_len = 1;

    }

    else {

        ctx->compute_len = 0;

    }



    if (ctx->compute_len) {

        /* save the brigade; we can't pass any data to the next

         * filter until we have the entire content length

         */
@@ -2313,12 +2314,12 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_content_length_filter(ap_filter_t *f, 
            ap_save_brigade(f, &ctx->saved, &b);

            return APR_SUCCESS;

        }

        ap_set_content_length(r, r->bytes_sent);

    }

    if (ctx->saved) {

        AP_BRIGADE_CONCAT(ctx->saved, b);

        b = ctx->saved;

    }

        ap_set_content_length(r, r->bytes_sent);

    }



    return ap_pass_brigade(f->next, b);

}