Commit a066f1e3 authored by Justin Erenkrantz's avatar Justin Erenkrantz
Browse files

Allow mod_deflate to be more tolerant of multiple content-encodings. 

- Tighten scope of a few affected variables (accepts, token).
- Look for gzip in r->headers_out (!) - if there, we've already compressed.
  (Previously, we'd look at r->headers_in which was bogus - we're output.)
- Switch the Accept-Encoding check to be case-insensitive per RFC 2616.
- Remove commented-out code.
- If C-E wasn't present or it was just "identity," set C-E to "gzip",
  otherwise, merge "gzip" onto the C-E list.

This patch was originally submitted by Ian and cleaned up and tested by
Justin.

Submitted by:	Ian Holsman
Reviewed by:	Justin Erenkrantz


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@95339 13f79535-47bb-0310-9956-ffa450edef68
parent f9d03dc1

modules/filters/mod_deflate.c

+25 −12
Changes for modules/filters/mod_deflate.c: 25 added lines, 12 removed lines.
Original line number Diff line number Diff line
@@ -231,10 +231,8 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
                                       apr_bucket_brigade *bb)

{

    apr_bucket *e;

    const char *accepts;

    request_rec *r = f->r;

    deflate_ctx *ctx = f->ctx;

    char *token = NULL;

    int zRC;

    deflate_filter_config *c = ap_get_module_config(r->server->module_config,

                                                    &deflate_module);
@@ -246,7 +244,8 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
     * we're in better shape.

     */

    if (!ctx) {

        char *buf;

        char *buf, *token;

        const char *encoding, *accepts;



        /* only work on main request/no subrequests */

        if (r->main) {
@@ -273,11 +272,24 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
            return ap_pass_brigade(f->next, bb);

        }



        /* content is already encoded, so don't encode it again */

        if (apr_table_get(r->headers_in, "Content-Encoding")) {

        /* Let's see what our current Content-Encoding is.

         * If gzip is present, don't gzip again.  (We could, but let's not.)

         */

        encoding = apr_table_get(r->headers_out, "Content-Encoding");

        if (encoding) {

            const char *tmp = encoding;



            token = ap_get_token(r->pool, &tmp, 0);

            while (token && token[0]) {

                if (!strcasecmp(token, "gzip")) {

                    ap_remove_output_filter(f);

                    return ap_pass_brigade(f->next, bb);			

                }

                /* Otherwise, skip token */

                tmp++;

                token = ap_get_token(r->pool, &tmp, 0);

            }

        }



        /* if they don't have the line, then they can't play */

        accepts = apr_table_get(r->headers_in, "Accept-Encoding");
@@ -287,7 +299,7 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
        }



        token = ap_get_token(r->pool, &accepts, 0);

        while (token && token[0] && strcmp(token, "gzip")) {

        while (token && token[0] && strcasecmp(token, "gzip")) {

            /* skip token */

            accepts++;

            token = ap_get_token(r->pool, &accepts, 0);
@@ -303,12 +315,7 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
        ctx = f->ctx = apr_pcalloc(r->pool, sizeof(*ctx));

        ctx->bb = apr_brigade_create(r->pool, f->c->bucket_alloc);

        ctx->buffer = apr_palloc(r->pool, c->bufferSize);

/*

        ctx->stream.zalloc = (alloc_func) 0;

        ctx->stream.zfree = (free_func) 0;

        ctx->stream.opaque = (voidpf) 0;

        ctx->crc = 0L;

*/



        zRC = deflateInit2(&ctx->stream, Z_BEST_SPEED, Z_DEFLATED,

                           c->windowSize, c->memlevel,

                           Z_DEFAULT_STRATEGY);
@@ -328,7 +335,13 @@ static apr_status_t deflate_out_filter(ap_filter_t *f, 
        e = apr_bucket_pool_create(buf, 10, r->pool, f->c->bucket_alloc);

        APR_BRIGADE_INSERT_TAIL(ctx->bb, e);



        /* If the entire Content-Encoding is "identity", we can replace it. */

        if (!encoding || !strcasecmp(encoding, "identity")) {

            apr_table_setn(r->headers_out, "Content-Encoding", "gzip");

        }

        else {

            apr_table_mergen(r->headers_out, "Content-Encoding", "gzip");

        }

        apr_table_setn(r->headers_out, "Vary", "Accept-Encoding");

        apr_table_unset(r->headers_out, "Content-Length");

    }