Example #1
0
static apr_status_t store_headers(cache_handle_t *h, request_rec *r, cache_info *info)
{
    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
                                                 &disk_cache_module);
    apr_status_t rv;
    apr_size_t amt;
    disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;

    disk_cache_info_t disk_info;
    struct iovec iov[2];

    /* This is flaky... we need to manage the cache_info differently */
    h->cache_obj->info = *info;

    if (r->headers_out) {
        const char *tmp;

        tmp = apr_table_get(r->headers_out, "Vary");

        if (tmp) {
            apr_array_header_t* varray;
            apr_uint32_t format = VARY_FORMAT_VERSION;

            /* If we were initially opened as a vary format, rollback
             * that internal state for the moment so we can recreate the
             * vary format hints in the appropriate directory.
             */
            if (dobj->prefix) {
                dobj->hdrsfile = dobj->prefix;
                dobj->prefix = NULL;
            }

            mkdir_structure(conf, dobj->hdrsfile, r->pool);

            rv = apr_file_mktemp(&dobj->tfd, dobj->tempfile,
                                 APR_CREATE | APR_WRITE | APR_BINARY | APR_EXCL,
                                 r->pool);

            if (rv != APR_SUCCESS) {
                return rv;
            }

            amt = sizeof(format);
            apr_file_write(dobj->tfd, &format, &amt);

            amt = sizeof(info->expire);
            apr_file_write(dobj->tfd, &info->expire, &amt);

            varray = apr_array_make(r->pool, 6, sizeof(char*));
            tokens_to_array(r->pool, tmp, varray);

            store_array(dobj->tfd, varray);

            apr_file_close(dobj->tfd);

            dobj->tfd = NULL;

            rv = safe_file_rename(conf, dobj->tempfile, dobj->hdrsfile,
                                  r->pool);
            if (rv != APR_SUCCESS) {
                ap_log_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
                    "disk_cache: rename tempfile to varyfile failed: %s -> %s",
                    dobj->tempfile, dobj->hdrsfile);
                apr_file_remove(dobj->tempfile, r->pool);
                return rv;
            }

            dobj->tempfile = apr_pstrcat(r->pool, conf->cache_root, AP_TEMPFILE, NULL);
            tmp = regen_key(r->pool, r->headers_in, varray, dobj->name);
            dobj->prefix = dobj->hdrsfile;
            dobj->hashfile = NULL;
            dobj->datafile = data_file(r->pool, conf, dobj, tmp);
            dobj->hdrsfile = header_file(r->pool, conf, dobj, tmp);
        }
    }


    rv = apr_file_mktemp(&dobj->hfd, dobj->tempfile,
                         APR_CREATE | APR_WRITE | APR_BINARY |
                         APR_BUFFERED | APR_EXCL, r->pool);

    if (rv != APR_SUCCESS) {
        return rv;
    }

    disk_info.format = DISK_FORMAT_VERSION;
    disk_info.date = info->date;
    disk_info.expire = info->expire;
    disk_info.entity_version = dobj->disk_info.entity_version++;
    disk_info.request_time = info->request_time;
    disk_info.response_time = info->response_time;
    disk_info.status = info->status;

    disk_info.name_len = strlen(dobj->name);

    iov[0].iov_base = (void*)&disk_info;
    iov[0].iov_len = sizeof(disk_cache_info_t);
    iov[1].iov_base = (void*)dobj->name;
    iov[1].iov_len = disk_info.name_len;

    rv = apr_file_writev(dobj->hfd, (const struct iovec *) &iov, 2, &amt);
    if (rv != APR_SUCCESS) {
        return rv;
    }

    if (r->headers_out) {
        apr_table_t *headers_out;

        headers_out = ap_cache_cacheable_hdrs_out(r->pool, r->headers_out,
                                                  r->server);

        if (!apr_table_get(headers_out, "Content-Type")
            && r->content_type) {
            apr_table_setn(headers_out, "Content-Type",
                           ap_make_content_type(r, r->content_type));
        }

        headers_out = apr_table_overlay(r->pool, headers_out,
                                        r->err_headers_out);
        rv = store_table(dobj->hfd, headers_out);
        if (rv != APR_SUCCESS) {
            return rv;
        }
    }

    /* Parse the vary header and dump those fields from the headers_in. */
    /* FIXME: Make call to the same thing cache_select calls to crack Vary. */
    if (r->headers_in) {
        apr_table_t *headers_in;

        headers_in = ap_cache_cacheable_hdrs_out(r->pool, r->headers_in,
                                                 r->server);
        rv = store_table(dobj->hfd, headers_in);
        if (rv != APR_SUCCESS) {
            return rv;
        }
    }

    apr_file_close(dobj->hfd); /* flush and close */

    /* Remove old file with the same name. If remove fails, then
     * perhaps we need to create the directory tree where we are
     * about to write the new headers file.
     */
    rv = apr_file_remove(dobj->hdrsfile, r->pool);
    if (rv != APR_SUCCESS) {
        mkdir_structure(conf, dobj->hdrsfile, r->pool);
    }

    rv = safe_file_rename(conf, dobj->tempfile, dobj->hdrsfile, r->pool);
    if (rv != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
                     "disk_cache: rename tempfile to hdrsfile failed: %s -> %s",
                     dobj->tempfile, dobj->hdrsfile);
        apr_file_remove(dobj->tempfile, r->pool);
        return rv;
    }

    dobj->tempfile = apr_pstrcat(r->pool, conf->cache_root, AP_TEMPFILE, NULL);

    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                 "disk_cache: Stored headers for URL %s",  dobj->name);
    return APR_SUCCESS;
}
AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
                                                         apr_bucket_brigade *bb)
{
    request_rec *r = f->r;
    conn_rec *c = r->connection;
    apr_bucket *e;
    apr_bucket_brigade *bsend;
    apr_bucket_brigade *tmpbb;
    apr_off_t range_start;
    apr_off_t range_end;
    apr_off_t clength = 0;
    apr_status_t rv;
    int found = 0;
    int num_ranges;
    char *boundary = NULL;
    char *bound_head = NULL;
    apr_array_header_t *indexes;
    indexes_t *idx;
    int i;
    int original_status;
    int max_ranges = get_max_ranges(r);

    /*
     * Iterate through the brigade until reaching EOS or a bucket with
     * unknown length.
     */
    for (e = APR_BRIGADE_FIRST(bb);
         (e != APR_BRIGADE_SENTINEL(bb) && !APR_BUCKET_IS_EOS(e)
          && e->length != (apr_size_t)-1);
         e = APR_BUCKET_NEXT(e)) {
        clength += e->length;
    }

    /*
     * Don't attempt to do byte range work if this brigade doesn't
     * contain an EOS, or if any of the buckets has an unknown length;
     * this avoids the cases where it is expensive to perform
     * byteranging (i.e. may require arbitrary amounts of memory).
     */
    if (!APR_BUCKET_IS_EOS(e) || clength <= 0) {
        ap_remove_output_filter(f);
        return ap_pass_brigade(f->next, bb);
    }

    original_status = r->status;
    num_ranges = ap_set_byterange(r, clength, &indexes);

    /* We have nothing to do, get out of the way. */
    if (num_ranges == 0 || (max_ranges >= 0 && num_ranges > max_ranges)) {
        r->status = original_status;
        ap_remove_output_filter(f);
        return ap_pass_brigade(f->next, bb);
    }

    /* this brigade holds what we will be sending */
    bsend = apr_brigade_create(r->pool, c->bucket_alloc);

    if (num_ranges < 0)
        return send_416(f, bsend);

    if (num_ranges > 1) {
        /* Is ap_make_content_type required here? */
        const char *orig_ct = ap_make_content_type(r, r->content_type);
        boundary = apr_psprintf(r->pool, "%" APR_UINT64_T_HEX_FMT "%lx",
                                (apr_uint64_t)r->request_time, c->id);

        ap_set_content_type(r, apr_pstrcat(r->pool, "multipart",
                                           use_range_x(r) ? "/x-" : "/",
                                           "byteranges; boundary=",
                                           boundary, NULL));

        if (strcasecmp(orig_ct, NO_CONTENT_TYPE)) {
            bound_head = apr_pstrcat(r->pool,
                                     CRLF "--", boundary,
                                     CRLF "Content-type: ",
                                     orig_ct,
                                     CRLF "Content-range: bytes ",
                                     NULL);
        }
        else {
            /* if we have no type for the content, do our best */
            bound_head = apr_pstrcat(r->pool,
                                     CRLF "--", boundary,
                                     CRLF "Content-range: bytes ",
                                     NULL);
        }
        ap_xlate_proto_to_ascii(bound_head, strlen(bound_head));
    }

    tmpbb = apr_brigade_create(r->pool, c->bucket_alloc);

    idx = (indexes_t *)indexes->elts;
    for (i = 0; i < indexes->nelts; i++, idx++) {
        range_start = idx->start;
        range_end = idx->end;

        rv = copy_brigade_range(bb, tmpbb, range_start, range_end);
        if (rv != APR_SUCCESS ) {
            ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
                          "copy_brigade_range() failed [%" APR_OFF_T_FMT
                          "-%" APR_OFF_T_FMT ",%" APR_OFF_T_FMT "]",
                          range_start, range_end, clength);
            continue;
        }
        found = 1;

        /*
         * For single range requests, we must produce Content-Range header.
         * Otherwise, we need to produce the multipart boundaries.
         */
        if (num_ranges == 1) {
            apr_table_setn(r->headers_out, "Content-Range",
                           apr_psprintf(r->pool, "bytes " BYTERANGE_FMT,
                                        range_start, range_end, clength));
        }
        else {
            char *ts;

            e = apr_bucket_pool_create(bound_head, strlen(bound_head),
                                       r->pool, c->bucket_alloc);
            APR_BRIGADE_INSERT_TAIL(bsend, e);

            ts = apr_psprintf(r->pool, BYTERANGE_FMT CRLF CRLF,
                              range_start, range_end, clength);
            ap_xlate_proto_to_ascii(ts, strlen(ts));
            e = apr_bucket_pool_create(ts, strlen(ts), r->pool,
                                       c->bucket_alloc);
            APR_BRIGADE_INSERT_TAIL(bsend, e);
        }

        APR_BRIGADE_CONCAT(bsend, tmpbb);
        if (i && !(i & 0x1F)) {
            /*
             * Every now and then, pass what we have down the filter chain.
             * In this case, the content-length filter cannot calculate and
             * set the content length and we must remove any Content-Length
             * header already present.
             */
            apr_table_unset(r->headers_out, "Content-Length");
            if ((rv = ap_pass_brigade(f->next, bsend)) != APR_SUCCESS)
                return rv;
            apr_brigade_cleanup(bsend);
        }
    }

    if (found == 0) {
        /* bsend is assumed to be empty if we get here. */
        return send_416(f, bsend);
    }

    if (num_ranges > 1) {
        char *end;

        /* add the final boundary */
        end = apr_pstrcat(r->pool, CRLF "--", boundary, "--" CRLF, NULL);
        ap_xlate_proto_to_ascii(end, strlen(end));
        e = apr_bucket_pool_create(end, strlen(end), r->pool, c->bucket_alloc);
        APR_BRIGADE_INSERT_TAIL(bsend, e);
    }

    e = apr_bucket_eos_create(c->bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(bsend, e);

    /* we're done with the original content - all of our data is in bsend. */
    apr_brigade_cleanup(bb);
    apr_brigade_destroy(tmpbb);

    /* send our multipart output */
    return ap_pass_brigade(f->next, bsend);
}
Example #3
0
static apr_status_t store_headers(cache_handle_t *h, request_rec *r, cache_info *info)
{
    cache_object_t *obj = h->cache_obj;
    mem_cache_object_t *mobj = (mem_cache_object_t*) obj->vobj;
    apr_table_t *headers_out;

    /*
     * The cache needs to keep track of the following information:
     * - Date, LastMod, Version, ReqTime, RespTime, ContentLength
     * - The original request headers (for Vary)
     * - The original response headers (for returning with a cached response)
     * - The body of the message
     */
    if (mobj->lock) {
        apr_thread_mutex_lock(mobj->lock);
    }
    mobj->req_hdrs = deep_table_copy(mobj->pool, r->headers_in);
    if (mobj->lock) {
        apr_thread_mutex_unlock(mobj->lock);
    }

    /* Precompute how much storage we need to hold the headers */
    headers_out = apr_table_overlay(r->pool, r->headers_out,
                                    r->err_headers_out);
    headers_out = ap_cache_cacheable_hdrs_out(r->pool, headers_out,
                                              r->server);

    /* If not set in headers_out, set Content-Type */
    if (!apr_table_get(headers_out, "Content-Type")
        && r->content_type) {
        apr_table_setn(headers_out, "Content-Type",
                       ap_make_content_type(r, r->content_type));
    }

    if (!apr_table_get(headers_out, "Content-Encoding")
        && r->content_encoding) {
        apr_table_setn(headers_out, "Content-Encoding",
                       r->content_encoding);
    }

    if (mobj->lock) {
        apr_thread_mutex_lock(mobj->lock);
    }
    mobj->header_out = deep_table_copy(mobj->pool, headers_out);
    if (mobj->lock) {
        apr_thread_mutex_unlock(mobj->lock);
    }

    /* Init the info struct */
    obj->info.status = info->status;
    if (info->date) {
        obj->info.date = info->date;
    }
    if (info->response_time) {
        obj->info.response_time = info->response_time;
    }
    if (info->request_time) {
        obj->info.request_time = info->request_time;
    }
    if (info->expire) {
        obj->info.expire = info->expire;
    }

    return APR_SUCCESS;
}
Example #4
0
/*
 * select a specific URL entity in the cache
 *
 * It is possible to store more than one entity per URL. Content
 * negotiation is used to select an entity. Once an entity is
 * selected, details of it are stored in the per request
 * config to save time when serving the request later.
 *
 * This function returns OK if successful, DECLINED if no
 * cached entity fits the bill.
 */
int cache_select_url(request_rec *r, char *url)
{
    cache_provider_list *list;
    apr_status_t rv;
    cache_handle_t *h;
    char *key;
    cache_request_rec *cache = (cache_request_rec *) 
                         ap_get_module_config(r->request_config, &cache_module);

    rv = cache_generate_key(r, r->pool, &key);
    if (rv != APR_SUCCESS) {
        return rv;
    }
    /* go through the cache types till we get a match */
    h = apr_palloc(r->pool, sizeof(cache_handle_t));

    list = cache->providers;

    while (list) {
        switch ((rv = list->provider->open_entity(h, r, key))) {
        case OK: {
            char *vary = NULL;
            const char *varyhdr = NULL;
            int fresh;

            if (list->provider->recall_headers(h, r) != APR_SUCCESS) {
                /* TODO: Handle this error */
                return DECLINED;
            }

            /*
             * Check Content-Negotiation - Vary
             * 
             * At this point we need to make sure that the object we found in
             * the cache is the same object that would be delivered to the
             * client, when the effects of content negotiation are taken into
             * effect.
             *
             * In plain english, we want to make sure that a language-negotiated
             * document in one language is not given to a client asking for a
             * language negotiated document in a different language by mistake.
             *
             * This code makes the assumption that the storage manager will
             * cache the req_hdrs if the response contains a Vary
             * header.
             *
             * RFC2616 13.6 and 14.44 describe the Vary mechanism.
             */
            if ((varyhdr = apr_table_get(h->resp_err_hdrs, "Vary")) == NULL) {
                varyhdr = apr_table_get(h->resp_hdrs, "Vary");
            }
            vary = apr_pstrdup(r->pool, varyhdr);
            while (vary && *vary) {
                char *name = vary;
                const char *h1, *h2;

                /* isolate header name */
                while (*vary && !apr_isspace(*vary) && (*vary != ','))
                    ++vary;
                while (*vary && (apr_isspace(*vary) || (*vary == ','))) {
                    *vary = '\0';
                    ++vary;
                }

                /*
                 * is this header in the request and the header in the cached
                 * request identical? If not, we give up and do a straight get
                 */
                h1 = apr_table_get(r->headers_in, name);
                h2 = apr_table_get(h->req_hdrs, name);
                if (h1 == h2) {
                    /* both headers NULL, so a match - do nothing */
                }
                else if (h1 && h2 && !strcmp(h1, h2)) {
                    /* both headers exist and are equal - do nothing */
                }
                else {
                    /* headers do not match, so Vary failed */
                    ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS,
                                r->server,
                                "cache_select_url(): Vary header mismatch.");
                    return DECLINED;
                }
            }

            cache->provider = list->provider;
            cache->provider_name = list->provider_name;

            /* Is our cached response fresh enough? */
            fresh = ap_cache_check_freshness(h, r);
            if (!fresh) {
                cache_info *info = &(h->cache_obj->info);

                /* Make response into a conditional */
                /* FIXME: What if the request is already conditional? */
                if (info && info->etag) {
                    /* if we have a cached etag */
                    cache->stale_headers = apr_table_copy(r->pool,
                                                          r->headers_in);
                    apr_table_set(r->headers_in, "If-None-Match", info->etag);
                    cache->stale_handle = h;
                }
                else if (info && info->lastmods) {
                    /* if we have a cached Last-Modified header */
                    cache->stale_headers = apr_table_copy(r->pool,
                                                          r->headers_in);
                    apr_table_set(r->headers_in, "If-Modified-Since",
                                  info->lastmods);
                    cache->stale_handle = h;
                }

                return DECLINED;
            }

            /* Okay, this response looks okay.  Merge in our stuff and go. */
            apr_table_setn(r->headers_out, "Content-Type",
                           ap_make_content_type(r, h->content_type));
            r->filename = apr_pstrdup(r->pool, h->cache_obj->info.filename);
            accept_headers(h, r);

            cache->handle = h;
            return OK;
        }
        case DECLINED: {
            /* try again with next cache type */
            list = list->next;
            continue;
        }
        default: {
            /* oo-er! an error */
            return rv;
        }
        }
    }
    return DECLINED;
}
Example #5
0
AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
                                                         apr_bucket_brigade *bb)
{
#define MIN_LENGTH(len1, len2) ((len1 > len2) ? len2 : len1)
    request_rec *r = f->r;
    conn_rec *c = r->connection;
    byterange_ctx *ctx;
    apr_bucket *e;
    apr_bucket_brigade *bsend;
    apr_off_t range_start;
    apr_off_t range_end;
    char *current;
    apr_off_t clength = 0;
    apr_status_t rv;
    int found = 0;
    int num_ranges;

    /* Iterate through the brigade until reaching EOS or a bucket with
     * unknown length. */
    for (e = APR_BRIGADE_FIRST(bb);
         (e != APR_BRIGADE_SENTINEL(bb) && !APR_BUCKET_IS_EOS(e)
          && e->length != (apr_size_t)-1);
         e = APR_BUCKET_NEXT(e)) {
        clength += e->length;
    }

    /* Don't attempt to do byte range work if this brigade doesn't
     * contain an EOS, or if any of the buckets has an unknown length;
     * this avoids the cases where it is expensive to perform
     * byteranging (i.e. may require arbitrary amounts of memory). */
    if (!APR_BUCKET_IS_EOS(e) || clength <= 0) {
        ap_remove_output_filter(f);
        return ap_pass_brigade(f->next, bb);
    }

    num_ranges = ap_set_byterange(r);

    /* We have nothing to do, get out of the way. */
    if (num_ranges == 0) {
        ap_remove_output_filter(f);
        return ap_pass_brigade(f->next, bb);
    }

    ctx = apr_pcalloc(r->pool, sizeof(*ctx));
    ctx->num_ranges = num_ranges;
    /* create a brigade in case we never call ap_save_brigade() */
    ctx->bb = apr_brigade_create(r->pool, c->bucket_alloc);

    if (ctx->num_ranges > 1) {
        /* Is ap_make_content_type required here? */
        const char *orig_ct = ap_make_content_type(r, r->content_type);
        ctx->boundary = apr_psprintf(r->pool, "%" APR_UINT64_T_HEX_FMT "%lx",
                                     (apr_uint64_t)r->request_time, (long) getpid());

        ap_set_content_type(r, apr_pstrcat(r->pool, "multipart",
                                           use_range_x(r) ? "/x-" : "/",
                                           "byteranges; boundary=",
                                           ctx->boundary, NULL));

        if (strcasecmp(orig_ct, NO_CONTENT_TYPE)) {
            ctx->bound_head = apr_pstrcat(r->pool,
                                          CRLF "--", ctx->boundary,
                                          CRLF "Content-type: ",
                                          orig_ct,
                                          CRLF "Content-range: bytes ",
                                          NULL);
        }
        else {
            /* if we have no type for the content, do our best */
            ctx->bound_head = apr_pstrcat(r->pool,
                                          CRLF "--", ctx->boundary,
                                          CRLF "Content-range: bytes ",
                                          NULL);
        }
        ap_xlate_proto_to_ascii(ctx->bound_head, strlen(ctx->bound_head));
    }

    /* this brigade holds what we will be sending */
    bsend = apr_brigade_create(r->pool, c->bucket_alloc);

    while ((current = ap_getword(r->pool, &r->range, ','))
           && (rv = parse_byterange(current, clength, &range_start,
                                    &range_end))) {
        apr_bucket *e2;
        apr_bucket *ec;

        if (rv == -1) {
            continue;
        }

        /* These calls to apr_brigage_partition should only fail in
         * pathological cases, e.g. a file being truncated whilst
         * being served. */
        if ((rv = apr_brigade_partition(bb, range_start, &ec)) != APR_SUCCESS) {
            ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
                          PARTITION_ERR_FMT, range_start, clength);
            continue;
        }
        if ((rv = apr_brigade_partition(bb, range_end+1, &e2)) != APR_SUCCESS) {
            ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
                          PARTITION_ERR_FMT, range_end+1, clength);
            continue;
        }

        found = 1;

        /* For single range requests, we must produce Content-Range header.
         * Otherwise, we need to produce the multipart boundaries.
         */
        if (ctx->num_ranges == 1) {
            apr_table_setn(r->headers_out, "Content-Range",
                           apr_psprintf(r->pool, "bytes " BYTERANGE_FMT,
                                        range_start, range_end, clength));
        }
        else {
            char *ts;

            e = apr_bucket_pool_create(ctx->bound_head, strlen(ctx->bound_head),
                                       r->pool, c->bucket_alloc);
            APR_BRIGADE_INSERT_TAIL(bsend, e);

            ts = apr_psprintf(r->pool, BYTERANGE_FMT CRLF CRLF,
                              range_start, range_end, clength);
            ap_xlate_proto_to_ascii(ts, strlen(ts));
            e = apr_bucket_pool_create(ts, strlen(ts), r->pool,
                                       c->bucket_alloc);
            APR_BRIGADE_INSERT_TAIL(bsend, e);
        }

        do {
            apr_bucket *foo;
            const char *str;
            apr_size_t len;

            if (apr_bucket_copy(ec, &foo) != APR_SUCCESS) {
                /* As above; this should not fail since the bucket has
                 * a known length, but just to be sure, this takes
                 * care of uncopyable buckets that do somehow manage
                 * to slip through.  */
                /* XXX: check for failure? */
                apr_bucket_read(ec, &str, &len, APR_BLOCK_READ);
                apr_bucket_copy(ec, &foo);
            }
            APR_BRIGADE_INSERT_TAIL(bsend, foo);
            ec = APR_BUCKET_NEXT(ec);
        } while (ec != e2);
    }

    if (found == 0) {
        ap_remove_output_filter(f);
        r->status = HTTP_OK;
        /* bsend is assumed to be empty if we get here. */
        e = ap_bucket_error_create(HTTP_RANGE_NOT_SATISFIABLE, NULL,
                                   r->pool, c->bucket_alloc);
        APR_BRIGADE_INSERT_TAIL(bsend, e);
        e = apr_bucket_eos_create(c->bucket_alloc);
        APR_BRIGADE_INSERT_TAIL(bsend, e);
        return ap_pass_brigade(f->next, bsend);
    }

    if (ctx->num_ranges > 1) {
        char *end;

        /* add the final boundary */
        end = apr_pstrcat(r->pool, CRLF "--", ctx->boundary, "--" CRLF, NULL);
        ap_xlate_proto_to_ascii(end, strlen(end));
        e = apr_bucket_pool_create(end, strlen(end), r->pool, c->bucket_alloc);
        APR_BRIGADE_INSERT_TAIL(bsend, e);
    }

    e = apr_bucket_eos_create(c->bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(bsend, e);

    /* we're done with the original content - all of our data is in bsend. */
    apr_brigade_cleanup(bb);

    /* send our multipart output */
    return ap_pass_brigade(f->next, bsend);
}