back out bogus "fix" for subrequest buckets using wrong pool

Changes with Apache 2.0.19-dev

  *) Fix a problem with subrequest buckets having private data in the

     wrong (i.e., subrequest) pool.  This could lead to a segfault

     later after the subrequest pool is cleaned up.  

     [Ryan Bloom, Jeff Trawick]

  *) Add a new request hook, error_log.  This phase allows modules

     to act on the error log string _after_ it has been written

     to the error log.  The goal for this hook is to allow monitoring

    apr_bucket *e = APR_BRIGADE_LAST(bb);

    if (APR_BUCKET_IS_EOS(e)) {

        apr_bucket_brigade *tmpbb;

        apr_bucket_delete(e);

        if (!APR_BRIGADE_EMPTY(bb)) { /* avoid brigade create/destroy */

            /* We need to be certain that any data in a bucket is valid

             * after the subrequest pool is cleared.

             */ 

            tmpbb = apr_brigade_create(f->r->main->pool);

            APR_BRIGADE_FOREACH(e, bb) {

                const char *str;

                apr_size_t n;

                apr_status_t rv;

                rv = apr_bucket_read(e, &str, &n, APR_BLOCK_READ);

                /* XXX handle rv! */

                /* This apr_brigade_write does not use a flush function

                   because we assume that we will not write enough data

                   into it to cause a flush. However, if we *do* write

                   "too much", then we could end up with transient

                   buckets which would suck. This works for now, but is

                   a bit shaky if changes are made to some of the

                   buffering sizes. Let's do an assert to prevent

                   potential future problems... */

                AP_DEBUG_ASSERT(AP_MIN_BYTES_TO_WRITE <=

                                APR_BUCKET_BUFF_SIZE);

                apr_brigade_write(tmpbb, NULL, NULL, str, n);

            }

            apr_brigade_destroy(bb);

            bb = tmpbb;

        }

    }

    return ap_pass_brigade(f->next, bb);

}