Adding upstream version 2.4.58.upstream/2.4.58

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1585 insertions, 0 deletions

diff --git a/modules/cache/mod_cache_disk.c b/modules/cache/mod_cache_disk.c
new file mode 100644
index 0000000..8d17a19
--- /dev/null
+++ b/modules/cache/mod_cache_disk.c
@@ -0,0 +1,1585 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "apr_lib.h"
+#include "apr_file_io.h"
+#include "apr_strings.h"
+#include "mod_cache.h"
+#include "mod_cache_disk.h"
+#include "http_config.h"
+#include "http_log.h"
+#include "http_core.h"
+#include "ap_provider.h"
+#include "util_filter.h"
+#include "util_script.h"
+#include "util_charset.h"
+
+/*
+ * mod_cache_disk: Disk Based HTTP 1.1 Cache.
+ *
+ * Flow to Find the .data file:
+ *   Incoming client requests URI /foo/bar/baz
+ *   Generate <hash> off of /foo/bar/baz
+ *   Open <hash>.header
+ *   Read in <hash>.header file (may contain Format #1 or Format #2)
+ *   If format #1 (Contains a list of Vary Headers):
+ *      Use each header name (from .header) with our request values (headers_in) to
+ *      regenerate <hash> using HeaderName+HeaderValue+.../foo/bar/baz
+ *      re-read in <hash>.header (must be format #2)
+ *   read in <hash>.data
+ *
+ * Format #1:
+ *   apr_uint32_t format;
+ *   apr_time_t expire;
+ *   apr_array_t vary_headers (delimited by CRLF)
+ *
+ * Format #2:
+ *   disk_cache_info_t (first sizeof(apr_uint32_t) bytes is the format)
+ *   entity name (dobj->name) [length is in disk_cache_info_t->name_len]
+ *   r->headers_out (delimited by CRLF)
+ *   CRLF
+ *   r->headers_in (delimited by CRLF)
+ *   CRLF
+ */
+
+module AP_MODULE_DECLARE_DATA cache_disk_module;
+
+/* Forward declarations */
+static int remove_entity(cache_handle_t *h);
+static apr_status_t store_headers(cache_handle_t *h, request_rec *r, cache_info *i);
+static apr_status_t store_body(cache_handle_t *h, request_rec *r, apr_bucket_brigade *in,
+                               apr_bucket_brigade *out);
+static apr_status_t recall_headers(cache_handle_t *h, request_rec *r);
+static apr_status_t recall_body(cache_handle_t *h, apr_pool_t *p, apr_bucket_brigade *bb);
+static apr_status_t read_array(request_rec *r, apr_array_header_t* arr,
+                               apr_file_t *file);
+
+/*
+ * Local static functions
+ */
+
+static char *header_file(apr_pool_t *p, disk_cache_conf *conf,
+                         disk_cache_object_t *dobj, const char *name)
+{
+    if (!dobj->hashfile) {
+        dobj->hashfile = ap_cache_generate_name(p, conf->dirlevels,
+                                                conf->dirlength, name);
+    }
+
+    if (dobj->prefix) {
+        return apr_pstrcat(p, dobj->prefix, CACHE_VDIR_SUFFIX "/",
+                           dobj->hashfile, CACHE_HEADER_SUFFIX, NULL);
+     }
+     else {
+        return apr_pstrcat(p, conf->cache_root, "/", dobj->hashfile,
+                           CACHE_HEADER_SUFFIX, NULL);
+     }
+}
+
+static char *data_file(apr_pool_t *p, disk_cache_conf *conf,
+                       disk_cache_object_t *dobj, const char *name)
+{
+    if (!dobj->hashfile) {
+        dobj->hashfile = ap_cache_generate_name(p, conf->dirlevels,
+                                                conf->dirlength, name);
+    }
+
+    if (dobj->prefix) {
+        return apr_pstrcat(p, dobj->prefix, CACHE_VDIR_SUFFIX "/",
+                           dobj->hashfile, CACHE_DATA_SUFFIX, NULL);
+     }
+     else {
+        return apr_pstrcat(p, conf->cache_root, "/", dobj->hashfile,
+                           CACHE_DATA_SUFFIX, NULL);
+     }
+}
+
+static apr_status_t mkdir_structure(disk_cache_conf *conf, const char *file, apr_pool_t *pool)
+{
+    apr_status_t rv;
+    char *p;
+
+    for (p = (char*)file + conf->cache_root_len + 1;;) {
+        p = strchr(p, '/');
+        if (!p)
+            break;
+        *p = '\0';
+
+        rv = apr_dir_make(file,
+                          APR_UREAD|APR_UWRITE|APR_UEXECUTE, pool);
+        if (rv != APR_SUCCESS && !APR_STATUS_IS_EEXIST(rv)) {
+            return rv;
+        }
+        *p = '/';
+        ++p;
+    }
+    return APR_SUCCESS;
+}
+
+/* htcacheclean may remove directories underneath us.
+ * So, we'll try renaming three times at a cost of 0.002 seconds.
+ */
+static apr_status_t safe_file_rename(disk_cache_conf *conf,
+                                     const char *src, const char *dest,
+                                     apr_pool_t *pool)
+{
+    apr_status_t rv;
+
+    rv = apr_file_rename(src, dest, pool);
+
+    if (rv != APR_SUCCESS) {
+        int i;
+
+        for (i = 0; i < 2 && rv != APR_SUCCESS; i++) {
+            /* 1000 micro-seconds aka 0.001 seconds. */
+            apr_sleep(1000);
+
+            rv = mkdir_structure(conf, dest, pool);
+            if (rv != APR_SUCCESS)
+                continue;
+
+            rv = apr_file_rename(src, dest, pool);
+        }
+    }
+
+    return rv;
+}
+
+static apr_status_t file_cache_el_final(disk_cache_conf *conf, disk_cache_file_t *file,
+                                        request_rec *r)
+{
+    apr_status_t rv = APR_SUCCESS;
+
+    /* This assumes that the tempfiles are on the same file system
+     * as the cache_root. If not, then we need a file copy/move
+     * rather than a rename.
+     */
+
+    /* move the file over */
+    if (file->tempfd) {
+
+        rv = safe_file_rename(conf, file->tempfile, file->file, file->pool);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00699)
+                    "rename tempfile to file failed:"
+                    " %s -> %s", file->tempfile, file->file);
+            apr_file_remove(file->tempfile, file->pool);
+        }
+
+        file->tempfd = NULL;
+    }
+
+    return rv;
+}
+
+static apr_status_t file_cache_temp_cleanup(void *dummy)
+{
+    disk_cache_file_t *file = (disk_cache_file_t *)dummy;
+
+    /* clean up the temporary file */
+    if (file->tempfd) {
+        apr_file_remove(file->tempfile, file->pool);
+        file->tempfd = NULL;
+    }
+    file->tempfile = NULL;
+    file->pool = NULL;
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t file_cache_create(disk_cache_conf *conf, disk_cache_file_t *file,
+                                      apr_pool_t *pool)
+{
+    file->pool = pool;
+    file->tempfile = apr_pstrcat(pool, conf->cache_root, AP_TEMPFILE, NULL);
+
+    apr_pool_cleanup_register(pool, file, file_cache_temp_cleanup, apr_pool_cleanup_null);
+
+    return APR_SUCCESS;
+}
+
+/* These two functions get and put state information into the data
+ * file for an ap_cache_el, this state information will be read
+ * and written transparent to clients of this module
+ */
+static int file_cache_recall_mydata(apr_file_t *fd, cache_info *info,
+                                    disk_cache_object_t *dobj, request_rec *r)
+{
+    apr_status_t rv;
+    char *urlbuff;
+    apr_size_t len;
+
+    /* read the data from the cache file */
+    len = sizeof(disk_cache_info_t);
+    rv = apr_file_read_full(fd, &dobj->disk_info, len, &len);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+
+    /* Store it away so we can get it later. */
+    info->status = dobj->disk_info.status;
+    info->date = dobj->disk_info.date;
+    info->expire = dobj->disk_info.expire;
+    info->request_time = dobj->disk_info.request_time;
+    info->response_time = dobj->disk_info.response_time;
+
+    memcpy(&info->control, &dobj->disk_info.control, sizeof(cache_control_t));
+
+    /* Note that we could optimize this by conditionally doing the palloc
+     * depending upon the size. */
+    urlbuff = apr_palloc(r->pool, dobj->disk_info.name_len + 1);
+    len = dobj->disk_info.name_len;
+    rv = apr_file_read_full(fd, urlbuff, len, &len);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+    urlbuff[dobj->disk_info.name_len] = '\0';
+
+    /* check that we have the same URL */
+    /* Would strncmp be correct? */
+    if (strcmp(urlbuff, dobj->name) != 0) {
+        return APR_EGENERAL;
+    }
+
+    return APR_SUCCESS;
+}
+
+static const char* regen_key(apr_pool_t *p, apr_table_t *headers,
+                             apr_array_header_t *varray, const char *oldkey)
+{
+    struct iovec *iov;
+    int i, k;
+    int nvec;
+    const char *header;
+    const char **elts;
+
+    nvec = (varray->nelts * 2) + 1;
+    iov = apr_palloc(p, sizeof(struct iovec) * nvec);
+    elts = (const char **) varray->elts;
+
+    /* TODO:
+     *    - Handle multiple-value headers better. (sort them?)
+     *    - Handle Case in-sensitive Values better.
+     *        This isn't the end of the world, since it just lowers the cache
+     *        hit rate, but it would be nice to fix.
+     *
+     * The majority are case insenstive if they are values (encoding etc).
+     * Most of rfc2616 is case insensitive on header contents.
+     *
+     * So the better solution may be to identify headers which should be
+     * treated case-sensitive?
+     *  HTTP URI's (3.2.3) [host and scheme are insensitive]
+     *  HTTP method (5.1.1)
+     *  HTTP-date values (3.3.1)
+     *  3.7 Media Types [excerpt]
+     *     The type, subtype, and parameter attribute names are case-
+     *     insensitive. Parameter values might or might not be case-sensitive,
+     *     depending on the semantics of the parameter name.
+     *  4.20 Except [excerpt]
+     *     Comparison of expectation values is case-insensitive for unquoted
+     *     tokens (including the 100-continue token), and is case-sensitive for
+     *     quoted-string expectation-extensions.
+     */
+
+    for (i=0, k=0; i < varray->nelts; i++) {
+        header = apr_table_get(headers, elts[i]);
+        if (!header) {
+            header = "";
+        }
+        iov[k].iov_base = (char*) elts[i];
+        iov[k].iov_len = strlen(elts[i]);
+        k++;
+        iov[k].iov_base = (char*) header;
+        iov[k].iov_len = strlen(header);
+        k++;
+    }
+    iov[k].iov_base = (char*) oldkey;
+    iov[k].iov_len = strlen(oldkey);
+    k++;
+
+    return apr_pstrcatv(p, iov, k, NULL);
+}
+
+static int array_alphasort(const void *fn1, const void *fn2)
+{
+    return strcmp(*(char**)fn1, *(char**)fn2);
+}
+
+static void tokens_to_array(apr_pool_t *p, const char *data,
+                            apr_array_header_t *arr)
+{
+    char *token;
+
+    while ((token = ap_get_list_item(p, &data)) != NULL) {
+        *((const char **) apr_array_push(arr)) = token;
+    }
+
+    /* Sort it so that "Vary: A, B" and "Vary: B, A" are stored the same. */
+    qsort((void *) arr->elts, arr->nelts,
+         sizeof(char *), array_alphasort);
+}
+
+/*
+ * Hook and mod_cache callback functions
+ */
+static int create_entity(cache_handle_t *h, request_rec *r, const char *key, apr_off_t len,
+                         apr_bucket_brigade *bb)
+{
+    disk_cache_dir_conf *dconf = ap_get_module_config(r->per_dir_config, &cache_disk_module);
+    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
+                                                 &cache_disk_module);
+    cache_object_t *obj;
+    disk_cache_object_t *dobj;
+    apr_pool_t *pool;
+
+    if (conf->cache_root == NULL) {
+        return DECLINED;
+    }
+
+    /* we don't support caching of range requests (yet) */
+    if (r->status == HTTP_PARTIAL_CONTENT) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00700)
+                "URL %s partial content response not cached",
+                key);
+        return DECLINED;
+    }
+
+    /* Note, len is -1 if unknown so don't trust it too hard */
+    if (len > dconf->maxfs) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00701)
+                "URL %s failed the size check "
+                "(%" APR_OFF_T_FMT " > %" APR_OFF_T_FMT ")",
+                key, len, dconf->maxfs);
+        return DECLINED;
+    }
+    if (len >= 0 && len < dconf->minfs) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00702)
+                "URL %s failed the size check "
+                "(%" APR_OFF_T_FMT " < %" APR_OFF_T_FMT ")",
+                key, len, dconf->minfs);
+        return DECLINED;
+    }
+
+    /* Allocate and initialize cache_object_t and disk_cache_object_t */
+    h->cache_obj = obj = apr_pcalloc(r->pool, sizeof(*obj));
+    obj->vobj = dobj = apr_pcalloc(r->pool, sizeof(*dobj));
+
+    obj->key = apr_pstrdup(r->pool, key);
+
+    dobj->name = obj->key;
+    dobj->prefix = NULL;
+    /* Save the cache root */
+    dobj->root = apr_pstrmemdup(r->pool, conf->cache_root, conf->cache_root_len);
+    dobj->root_len = conf->cache_root_len;
+
+    apr_pool_create(&pool, r->pool);
+    apr_pool_tag(pool, "mod_cache (create_entity)");
+
+    file_cache_create(conf, &dobj->hdrs, pool);
+    file_cache_create(conf, &dobj->vary, pool);
+    file_cache_create(conf, &dobj->data, pool);
+
+    dobj->data.file = data_file(r->pool, conf, dobj, key);
+    dobj->hdrs.file = header_file(r->pool, conf, dobj, key);
+    dobj->vary.file = header_file(r->pool, conf, dobj, key);
+
+    dobj->disk_info.header_only = r->header_only;
+
+    return OK;
+}
+
+static int open_entity(cache_handle_t *h, request_rec *r, const char *key)
+{
+    apr_uint32_t format;
+    apr_size_t len;
+    const char *nkey;
+    apr_status_t rc;
+    static int error_logged = 0;
+    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
+                                                 &cache_disk_module);
+#ifdef APR_SENDFILE_ENABLED
+    core_dir_config *coreconf = ap_get_core_module_config(r->per_dir_config);
+#endif
+    apr_finfo_t finfo;
+    cache_object_t *obj;
+    cache_info *info;
+    disk_cache_object_t *dobj;
+    int flags;
+    apr_pool_t *pool;
+
+    h->cache_obj = NULL;
+
+    /* Look up entity keyed to 'url' */
+    if (conf->cache_root == NULL) {
+        if (!error_logged) {
+            error_logged = 1;
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00703)
+                    "Cannot cache files to disk without a CacheRoot specified.");
+        }
+        return DECLINED;
+    }
+
+    /* Create and init the cache object */
+    obj = apr_pcalloc(r->pool, sizeof(cache_object_t));
+    dobj = apr_pcalloc(r->pool, sizeof(disk_cache_object_t));
+
+    info = &(obj->info);
+
+    /* Open the headers file */
+    dobj->prefix = NULL;
+
+    /* Save the cache root */
+    dobj->root = apr_pstrmemdup(r->pool, conf->cache_root, conf->cache_root_len);
+    dobj->root_len = conf->cache_root_len;
+
+    dobj->vary.file = header_file(r->pool, conf, dobj, key);
+    flags = APR_READ|APR_BINARY|APR_BUFFERED;
+    rc = apr_file_open(&dobj->vary.fd, dobj->vary.file, flags, 0, r->pool);
+    if (rc != APR_SUCCESS) {
+        return DECLINED;
+    }
+
+    /* read the format from the cache file */
+    len = sizeof(format);
+    apr_file_read_full(dobj->vary.fd, &format, len, &len);
+
+    if (format == VARY_FORMAT_VERSION) {
+        apr_array_header_t* varray;
+        apr_time_t expire;
+
+        len = sizeof(expire);
+        apr_file_read_full(dobj->vary.fd, &expire, len, &len);
+
+        varray = apr_array_make(r->pool, 5, sizeof(char*));
+        rc = read_array(r, varray, dobj->vary.fd);
+        if (rc != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(00704)
+                    "Cannot parse vary header file: %s",
+                    dobj->vary.file);
+            apr_file_close(dobj->vary.fd);
+            return DECLINED;
+        }
+        apr_file_close(dobj->vary.fd);
+
+        nkey = regen_key(r->pool, r->headers_in, varray, key);
+
+        dobj->hashfile = NULL;
+        dobj->prefix = dobj->vary.file;
+        dobj->hdrs.file = header_file(r->pool, conf, dobj, nkey);
+
+        flags = APR_READ|APR_BINARY|APR_BUFFERED;
+        rc = apr_file_open(&dobj->hdrs.fd, dobj->hdrs.file, flags, 0, r->pool);
+        if (rc != APR_SUCCESS) {
+            return DECLINED;
+        }
+    }
+    else if (format != DISK_FORMAT_VERSION) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00705)
+                "File '%s' has a version mismatch. File had version: %d.",
+                dobj->vary.file, format);
+        apr_file_close(dobj->vary.fd);
+        return DECLINED;
+    }
+    else {
+        apr_off_t offset = 0;
+
+        /* oops, not vary as it turns out */
+        dobj->hdrs.fd = dobj->vary.fd;
+        dobj->vary.fd = NULL;
+        dobj->hdrs.file = dobj->vary.file;
+
+        /* This wasn't a Vary Format file, so we must seek to the
+         * start of the file again, so that later reads work.
+         */
+        apr_file_seek(dobj->hdrs.fd, APR_SET, &offset);
+        nkey = key;
+    }
+
+    obj->key = nkey;
+    dobj->key = nkey;
+    dobj->name = key;
+
+    apr_pool_create(&pool, r->pool);
+    apr_pool_tag(pool, "mod_cache (open_entity)");
+
+    file_cache_create(conf, &dobj->hdrs, pool);
+    file_cache_create(conf, &dobj->vary, pool);
+    file_cache_create(conf, &dobj->data, pool);
+
+    dobj->data.file = data_file(r->pool, conf, dobj, nkey);
+
+    /* Read the bytes to setup the cache_info fields */
+    rc = file_cache_recall_mydata(dobj->hdrs.fd, info, dobj, r);
+    if (rc != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(00706)
+                "Cannot read header file %s", dobj->hdrs.file);
+        apr_file_close(dobj->hdrs.fd);
+        return DECLINED;
+    }
+
+
+    /* Is this a cached HEAD request? */
+    if (dobj->disk_info.header_only && !r->header_only) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(00707)
+                "HEAD request cached, non-HEAD requested, ignoring: %s",
+                dobj->hdrs.file);
+        apr_file_close(dobj->hdrs.fd);
+        return DECLINED;
+    }
+
+    /* Open the data file */
+    if (dobj->disk_info.has_body) {
+        flags = APR_READ | APR_BINARY;
+#ifdef APR_SENDFILE_ENABLED
+        /* When we are in the quick handler we don't have the per-directory
+         * configuration, so this check only takes the global setting of
+         * the EnableSendFile directive into account.
+         */
+        flags |= AP_SENDFILE_ENABLED(coreconf->enable_sendfile);
+#endif
+        rc = apr_file_open(&dobj->data.fd, dobj->data.file, flags, 0, r->pool);
+        if (rc != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(00708)
+                    "Cannot open data file %s", dobj->data.file);
+            apr_file_close(dobj->hdrs.fd);
+            return DECLINED;
+        }
+
+        rc = apr_file_info_get(&finfo, APR_FINFO_SIZE | APR_FINFO_IDENT,
+                dobj->data.fd);
+        if (rc == APR_SUCCESS) {
+            dobj->file_size = finfo.size;
+        }
+
+        /* Atomic check - does the body file belong to the header file? */
+        if (dobj->disk_info.inode == finfo.inode &&
+                dobj->disk_info.device == finfo.device) {
+
+            /* Initialize the cache_handle callback functions */
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00709)
+                    "Recalled cached URL info header %s", dobj->name);
+
+            /* make the configuration stick */
+            h->cache_obj = obj;
+            obj->vobj = dobj;
+
+            return OK;
+        }
+
+    }
+    else {
+
+        /* make the configuration stick */
+        h->cache_obj = obj;
+        obj->vobj = dobj;
+
+        return OK;
+    }
+
+    /* Oh dear, no luck matching header to the body */
+    ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00710)
+            "Cached URL info header '%s' didn't match body, ignoring this entry",
+            dobj->name);
+
+    apr_file_close(dobj->hdrs.fd);
+    return DECLINED;
+}
+
+static void close_disk_cache_fd(disk_cache_file_t *file)
+{
+   if (file->fd != NULL) {
+       apr_file_close(file->fd);
+       file->fd = NULL;
+   }
+   if (file->tempfd != NULL) {
+       apr_file_close(file->tempfd);
+       file->tempfd = NULL;
+   }
+}
+
+static int remove_entity(cache_handle_t *h)
+{
+    disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;
+
+    close_disk_cache_fd(&(dobj->hdrs));
+    close_disk_cache_fd(&(dobj->vary));
+    close_disk_cache_fd(&(dobj->data));
+
+    /* Null out the cache object pointer so next time we start from scratch  */
+    h->cache_obj = NULL;
+    return OK;
+}
+
+static int remove_url(cache_handle_t *h, request_rec *r)
+{
+    apr_status_t rc;
+    disk_cache_object_t *dobj;
+
+    /* Get disk cache object from cache handle */
+    dobj = (disk_cache_object_t *) h->cache_obj->vobj;
+    if (!dobj) {
+        return DECLINED;
+    }
+
+    /* Delete headers file */
+    if (dobj->hdrs.file) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00711)
+                "Deleting %s from cache.", dobj->hdrs.file);
+
+        rc = apr_file_remove(dobj->hdrs.file, r->pool);
+        if ((rc != APR_SUCCESS) && !APR_STATUS_IS_ENOENT(rc)) {
+            /* Will only result in an output if httpd is started with -e debug.
+             * For reason see log_error_core for the case s == NULL.
+             */
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rc, r, APLOGNO(00712)
+                    "Failed to delete headers file %s from cache.",
+                    dobj->hdrs.file);
+            return DECLINED;
+        }
+    }
+
+    /* Delete data file */
+    if (dobj->data.file) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00713)
+                "Deleting %s from cache.", dobj->data.file);
+
+        rc = apr_file_remove(dobj->data.file, r->pool);
+        if ((rc != APR_SUCCESS) && !APR_STATUS_IS_ENOENT(rc)) {
+            /* Will only result in an output if httpd is started with -e debug.
+             * For reason see log_error_core for the case s == NULL.
+             */
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rc, r, APLOGNO(00714)
+                    "Failed to delete data file %s from cache.",
+                    dobj->data.file);
+            return DECLINED;
+        }
+    }
+
+    /* now delete directories as far as possible up to our cache root */
+    if (dobj->root) {
+        const char *str_to_copy;
+
+        str_to_copy = dobj->hdrs.file ? dobj->hdrs.file : dobj->data.file;
+        if (str_to_copy) {
+            char *dir, *slash, *q;
+
+            dir = apr_pstrdup(r->pool, str_to_copy);
+
+            /* remove filename */
+            slash = strrchr(dir, '/');
+            *slash = '\0';
+
+            /*
+             * now walk our way back to the cache root, delete everything
+             * in the way as far as possible
+             *
+             * Note: due to the way we constructed the file names in
+             * header_file and data_file, we are guaranteed that the
+             * cache_root is suffixed by at least one '/' which will be
+             * turned into a terminating null by this loop.  Therefore,
+             * we won't either delete or go above our cache root.
+             */
+            for (q = dir + dobj->root_len; *q ; ) {
+                 ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00715)
+                        "Deleting directory %s from cache", dir);
+
+                 rc = apr_dir_remove(dir, r->pool);
+                 if (rc != APR_SUCCESS && !APR_STATUS_IS_ENOENT(rc)) {
+                    break;
+                 }
+                 slash = strrchr(q, '/');
+                 *slash = '\0';
+            }
+        }
+    }
+
+    return OK;
+}
+
+static apr_status_t read_array(request_rec *r, apr_array_header_t* arr,
+                               apr_file_t *file)
+{
+    char w[MAX_STRING_LEN];
+    apr_size_t p;
+    apr_status_t rv;
+
+    while (1) {
+        rv = apr_file_gets(w, MAX_STRING_LEN - 1, file);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00716)
+                          "Premature end of vary array.");
+            return rv;
+        }
+
+        p = strlen(w);
+        if (p > 0 && w[p - 1] == '\n') {
+            if (p > 1 && w[p - 2] == CR) {
+                w[p - 2] = '\0';
+            }
+            else {
+                w[p - 1] = '\0';
+            }
+        }
+
+        /* If we've finished reading the array, break out of the loop. */
+        if (w[0] == '\0') {
+            break;
+        }
+
+        *((const char **) apr_array_push(arr)) = apr_pstrdup(r->pool, w);
+    }
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t store_array(apr_file_t *fd, apr_array_header_t* arr)
+{
+    int i;
+    apr_status_t rv;
+    struct iovec iov[2];
+    apr_size_t amt;
+    const char **elts;
+
+    elts = (const char **) arr->elts;
+
+    for (i = 0; i < arr->nelts; i++) {
+        iov[0].iov_base = (char*) elts[i];
+        iov[0].iov_len = strlen(elts[i]);
+        iov[1].iov_base = CRLF;
+        iov[1].iov_len = sizeof(CRLF) - 1;
+
+        rv = apr_file_writev_full(fd, (const struct iovec *) &iov, 2, &amt);
+        if (rv != APR_SUCCESS) {
+            return rv;
+        }
+    }
+
+    iov[0].iov_base = CRLF;
+    iov[0].iov_len = sizeof(CRLF) - 1;
+
+    return apr_file_writev_full(fd, (const struct iovec *) &iov, 1, &amt);
+}
+
+static apr_status_t read_table(cache_handle_t *handle, request_rec *r,
+                               apr_table_t *table, apr_file_t *file)
+{
+    char w[MAX_STRING_LEN];
+    char *l;
+    apr_size_t p;
+    apr_status_t rv;
+
+    while (1) {
+
+        /* ### What about APR_EOF? */
+        rv = apr_file_gets(w, MAX_STRING_LEN - 1, file);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(00717)
+                          "Premature end of cache headers.");
+            return rv;
+        }
+
+        /* Delete terminal (CR?)LF */
+
+        p = strlen(w);
+        /* Indeed, the host's '\n':
+           '\012' for UNIX; '\015' for MacOS; '\025' for OS/390
+           -- whatever the script generates.
+        */
+        if (p > 0 && w[p - 1] == '\n') {
+            if (p > 1 && w[p - 2] == CR) {
+                w[p - 2] = '\0';
+            }
+            else {
+                w[p - 1] = '\0';
+            }
+        }
+
+        /* If we've finished reading the headers, break out of the loop. */
+        if (w[0] == '\0') {
+            break;
+        }
+
+#if APR_CHARSET_EBCDIC
+        /* Chances are that we received an ASCII header text instead of
+         * the expected EBCDIC header lines. Try to auto-detect:
+         */
+        if (!(l = strchr(w, ':'))) {
+            int maybeASCII = 0, maybeEBCDIC = 0;
+            unsigned char *cp, native;
+            apr_size_t inbytes_left, outbytes_left;
+
+            for (cp = w; *cp != '\0'; ++cp) {
+                native = apr_xlate_conv_byte(ap_hdrs_from_ascii, *cp);
+                if (apr_isprint(*cp) && !apr_isprint(native))
+                    ++maybeEBCDIC;
+                if (!apr_isprint(*cp) && apr_isprint(native))
+                    ++maybeASCII;
+            }
+            if (maybeASCII > maybeEBCDIC) {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00718)
+                        "CGI Interface Error: Script headers apparently ASCII: (CGI = %s)",
+                        r->filename);
+                inbytes_left = outbytes_left = cp - w;
+                apr_xlate_conv_buffer(ap_hdrs_from_ascii,
+                                      w, &inbytes_left, w, &outbytes_left);
+            }
+        }
+#endif /*APR_CHARSET_EBCDIC*/
+
+        /* if we see a bogus header don't ignore it. Shout and scream */
+        if (!(l = strchr(w, ':'))) {
+            return APR_EGENERAL;
+        }
+
+        *l++ = '\0';
+        while (apr_isspace(*l)) {
+            ++l;
+        }
+
+        apr_table_add(table, w, l);
+    }
+
+    return APR_SUCCESS;
+}
+
+/*
+ * Reads headers from a buffer and returns an array of headers.
+ * Returns NULL on file error
+ * This routine tries to deal with too long lines and continuation lines.
+ * @@@: XXX: FIXME: currently the headers are passed thru un-merged.
+ * Is that okay, or should they be collapsed where possible?
+ */
+static apr_status_t recall_headers(cache_handle_t *h, request_rec *r)
+{
+    disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;
+    apr_status_t rv;
+
+    /* This case should not happen... */
+    if (!dobj->hdrs.fd) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00719)
+                "recalling headers; but no header fd for %s", dobj->name);
+        return APR_NOTFOUND;
+    }
+
+    h->req_hdrs = apr_table_make(r->pool, 20);
+    h->resp_hdrs = apr_table_make(r->pool, 20);
+
+    /* Call routine to read the header lines/status line */
+    rv = read_table(h, r, h->resp_hdrs, dobj->hdrs.fd);
+    if (rv != APR_SUCCESS) { 
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02987) 
+                      "Error reading response headers from %s for %s",
+                      dobj->hdrs.file, dobj->name);
+    }
+    rv = read_table(h, r, h->req_hdrs, dobj->hdrs.fd);
+    if (rv != APR_SUCCESS) { 
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02988) 
+                      "Error reading request headers from %s for %s",
+                      dobj->hdrs.file, dobj->name);
+    }
+
+    apr_file_close(dobj->hdrs.fd);
+
+    ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00720)
+            "Recalled headers for URL %s", dobj->name);
+    return APR_SUCCESS;
+}
+
+static apr_status_t recall_body(cache_handle_t *h, apr_pool_t *p, apr_bucket_brigade *bb)
+{
+    disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;
+
+    if (dobj->data.fd) {
+        apr_brigade_insert_file(bb, dobj->data.fd, 0, dobj->file_size, p);
+    }
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t store_table(apr_file_t *fd, apr_table_t *table)
+{
+    int i;
+    apr_status_t rv;
+    struct iovec iov[4];
+    apr_size_t amt;
+    apr_table_entry_t *elts;
+
+    elts = (apr_table_entry_t *) apr_table_elts(table)->elts;
+    for (i = 0; i < apr_table_elts(table)->nelts; ++i) {
+        if (elts[i].key != NULL) {
+            iov[0].iov_base = elts[i].key;
+            iov[0].iov_len = strlen(elts[i].key);
+            iov[1].iov_base = ": ";
+            iov[1].iov_len = sizeof(": ") - 1;
+            iov[2].iov_base = elts[i].val;
+            iov[2].iov_len = strlen(elts[i].val);
+            iov[3].iov_base = CRLF;
+            iov[3].iov_len = sizeof(CRLF) - 1;
+
+            rv = apr_file_writev_full(fd, (const struct iovec *) &iov, 4, &amt);
+            if (rv != APR_SUCCESS) {
+                return rv;
+            }
+        }
+    }
+    iov[0].iov_base = CRLF;
+    iov[0].iov_len = sizeof(CRLF) - 1;
+    rv = apr_file_writev_full(fd, (const struct iovec *) &iov, 1, &amt);
+    return rv;
+}
+
+static apr_status_t store_headers(cache_handle_t *h, request_rec *r, cache_info *info)
+{
+    disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;
+
+    memcpy(&h->cache_obj->info, info, sizeof(cache_info));
+
+    if (r->headers_out) {
+        dobj->headers_out = ap_cache_cacheable_headers_out(r);
+    }
+
+    if (r->headers_in) {
+        dobj->headers_in = ap_cache_cacheable_headers_in(r);
+    }
+
+    if (r->header_only && r->status != HTTP_NOT_MODIFIED) {
+        dobj->disk_info.header_only = 1;
+    }
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t write_headers(cache_handle_t *h, request_rec *r)
+{
+    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
+                                                 &cache_disk_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];
+
+    memset(&disk_info, 0, sizeof(disk_cache_info_t));
+
+    if (dobj->headers_out) {
+        const char *tmp;
+
+        tmp = apr_table_get(dobj->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->hdrs.file = dobj->prefix;
+                dobj->prefix = NULL;
+            }
+
+            rv = mkdir_structure(conf, dobj->hdrs.file, r->pool);
+            if (rv == APR_SUCCESS) {
+                rv = apr_file_mktemp(&dobj->vary.tempfd, dobj->vary.tempfile,
+                                     APR_CREATE | APR_WRITE | APR_BINARY | APR_EXCL,
+                                     dobj->vary.pool);
+            }
+
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00721)
+                        "could not create vary file %s",
+                        dobj->vary.tempfile);
+                return rv;
+            }
+
+            amt = sizeof(format);
+            rv = apr_file_write_full(dobj->vary.tempfd, &format, amt, NULL);
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00722)
+                        "could not write to vary file %s",
+                        dobj->vary.tempfile);
+                apr_file_close(dobj->vary.tempfd);
+                apr_pool_destroy(dobj->vary.pool);
+                return rv;
+            }
+
+            amt = sizeof(h->cache_obj->info.expire);
+            rv = apr_file_write_full(dobj->vary.tempfd,
+                                     &h->cache_obj->info.expire, amt, NULL);
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00723)
+                        "could not write to vary file %s",
+                        dobj->vary.tempfile);
+                apr_file_close(dobj->vary.tempfd);
+                apr_pool_destroy(dobj->vary.pool);
+                return rv;
+            }
+
+            varray = apr_array_make(r->pool, 6, sizeof(char*));
+            tokens_to_array(r->pool, tmp, varray);
+
+            store_array(dobj->vary.tempfd, varray);
+
+            rv = apr_file_close(dobj->vary.tempfd);
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00724)
+                        "could not close vary file %s",
+                        dobj->vary.tempfile);
+                apr_pool_destroy(dobj->vary.pool);
+                return rv;
+            }
+
+            tmp = regen_key(r->pool, dobj->headers_in, varray, dobj->name);
+            dobj->prefix = dobj->hdrs.file;
+            dobj->hashfile = NULL;
+            dobj->data.file = data_file(r->pool, conf, dobj, tmp);
+            dobj->hdrs.file = header_file(r->pool, conf, dobj, tmp);
+        }
+    }
+
+
+    rv = apr_file_mktemp(&dobj->hdrs.tempfd, dobj->hdrs.tempfile,
+                         APR_CREATE | APR_WRITE | APR_BINARY |
+                         APR_BUFFERED | APR_EXCL, dobj->hdrs.pool);
+
+    if (rv != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00725)
+                "could not create header file %s",
+                dobj->hdrs.tempfile);
+        return rv;
+    }
+
+    disk_info.format = DISK_FORMAT_VERSION;
+    disk_info.date = h->cache_obj->info.date;
+    disk_info.expire = h->cache_obj->info.expire;
+    disk_info.entity_version = dobj->disk_info.entity_version++;
+    disk_info.request_time = h->cache_obj->info.request_time;
+    disk_info.response_time = h->cache_obj->info.response_time;
+    disk_info.status = h->cache_obj->info.status;
+    disk_info.inode = dobj->disk_info.inode;
+    disk_info.device = dobj->disk_info.device;
+    disk_info.has_body = dobj->disk_info.has_body;
+    disk_info.header_only = dobj->disk_info.header_only;
+
+    disk_info.name_len = strlen(dobj->name);
+
+    memcpy(&disk_info.control, &h->cache_obj->info.control, sizeof(cache_control_t));
+
+    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_full(dobj->hdrs.tempfd, (const struct iovec *) &iov,
+                              2, &amt);
+    if (rv != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00726)
+                "could not write info to header file %s",
+                dobj->hdrs.tempfile);
+        apr_file_close(dobj->hdrs.tempfd);
+        apr_pool_destroy(dobj->hdrs.pool);
+        return rv;
+    }
+
+    if (dobj->headers_out) {
+        rv = store_table(dobj->hdrs.tempfd, dobj->headers_out);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00727)
+                    "could not write out-headers to header file %s",
+                    dobj->hdrs.tempfile);
+            apr_file_close(dobj->hdrs.tempfd);
+            apr_pool_destroy(dobj->hdrs.pool);
+            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 (dobj->headers_in) {
+        rv = store_table(dobj->hdrs.tempfd, dobj->headers_in);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00728)
+                    "could not write in-headers to header file %s",
+                    dobj->hdrs.tempfile);
+            apr_file_close(dobj->hdrs.tempfd);
+            apr_pool_destroy(dobj->hdrs.pool);
+            return rv;
+        }
+    }
+
+    rv = apr_file_close(dobj->hdrs.tempfd); /* flush and close */
+    if (rv != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, r, APLOGNO(00729)
+                "could not close header file %s",
+                dobj->hdrs.tempfile);
+        apr_pool_destroy(dobj->hdrs.pool);
+        return rv;
+    }
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t store_body(cache_handle_t *h, request_rec *r,
+                               apr_bucket_brigade *in, apr_bucket_brigade *out)
+{
+    apr_bucket *e;
+    apr_status_t rv = APR_SUCCESS;
+    disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;
+    disk_cache_dir_conf *dconf = ap_get_module_config(r->per_dir_config, &cache_disk_module);
+    int seen_eos = 0;
+
+    if (!dobj->offset) {
+        dobj->offset = dconf->readsize;
+    }
+    if (!dobj->timeout && dconf->readtime) {
+        dobj->timeout = apr_time_now() + dconf->readtime;
+    }
+
+    if (dobj->offset) {
+        apr_brigade_partition(in, dobj->offset, &e);
+    }
+
+    while (APR_SUCCESS == rv && !APR_BRIGADE_EMPTY(in)) {
+        const char *str;
+        apr_size_t length, written;
+
+        e = APR_BRIGADE_FIRST(in);
+
+        /* are we done completely? if so, pass any trailing buckets right through */
+        if (dobj->done || !dobj->data.pool) {
+            APR_BUCKET_REMOVE(e);
+            APR_BRIGADE_INSERT_TAIL(out, e);
+            continue;
+        }
+
+        /* have we seen eos yet? */
+        if (APR_BUCKET_IS_EOS(e)) {
+            seen_eos = 1;
+            dobj->done = 1;
+            APR_BUCKET_REMOVE(e);
+            APR_BRIGADE_INSERT_TAIL(out, e);
+            break;
+        }
+
+        /* honour flush buckets, we'll get called again */
+        if (APR_BUCKET_IS_FLUSH(e)) {
+            APR_BUCKET_REMOVE(e);
+            APR_BRIGADE_INSERT_TAIL(out, e);
+            break;
+        }
+
+        /* metadata buckets are preserved as is */
+        if (APR_BUCKET_IS_METADATA(e)) {
+            APR_BUCKET_REMOVE(e);
+            APR_BRIGADE_INSERT_TAIL(out, e);
+            continue;
+        }
+
+        /* read the bucket, write to the cache */
+        rv = apr_bucket_read(e, &str, &length, APR_BLOCK_READ);
+        APR_BUCKET_REMOVE(e);
+        APR_BRIGADE_INSERT_TAIL(out, e);
+        if (rv != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00730)
+                    "Error when reading bucket for URL %s",
+                    h->cache_obj->key);
+            /* Remove the intermediate cache file and return non-APR_SUCCESS */
+            apr_pool_destroy(dobj->data.pool);
+            return rv;
+        }
+
+        /* don't write empty buckets to the cache */
+        if (!length) {
+            continue;
+        }
+
+        if (!dobj->disk_info.header_only) {
+
+            /* Attempt to create the data file at the last possible moment, if
+             * the body is empty, we don't write a file at all, and save an inode.
+             */
+            if (!dobj->data.tempfd) {
+                apr_finfo_t finfo;
+                rv = apr_file_mktemp(&dobj->data.tempfd, dobj->data.tempfile,
+                        APR_CREATE | APR_WRITE | APR_BINARY | APR_BUFFERED
+                                | APR_EXCL, dobj->data.pool);
+                if (rv != APR_SUCCESS) {
+                    apr_pool_destroy(dobj->data.pool);
+                    return rv;
+                }
+                dobj->file_size = 0;
+                rv = apr_file_info_get(&finfo, APR_FINFO_IDENT,
+                        dobj->data.tempfd);
+                if (rv != APR_SUCCESS) {
+                    apr_pool_destroy(dobj->data.pool);
+                    return rv;
+                }
+                dobj->disk_info.device = finfo.device;
+                dobj->disk_info.inode = finfo.inode;
+                dobj->disk_info.has_body = 1;
+            }
+
+            /* write to the cache, leave if we fail */
+            rv = apr_file_write_full(dobj->data.tempfd, str, length, &written);
+            if (rv != APR_SUCCESS) {
+                ap_log_rerror(
+                        APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00731) "Error when writing cache file for URL %s", h->cache_obj->key);
+                /* Remove the intermediate cache file and return non-APR_SUCCESS */
+                apr_pool_destroy(dobj->data.pool);
+                return rv;
+            }
+            dobj->file_size += written;
+            if (dobj->file_size > dconf->maxfs) {
+                ap_log_rerror(
+                        APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00732) "URL %s failed the size check "
+                        "(%" APR_OFF_T_FMT ">%" APR_OFF_T_FMT ")", h->cache_obj->key, dobj->file_size, dconf->maxfs);
+                /* Remove the intermediate cache file and return non-APR_SUCCESS */
+                apr_pool_destroy(dobj->data.pool);
+                return APR_EGENERAL;
+            }
+
+        }
+
+        /* have we reached the limit of how much we're prepared to write in one
+         * go? If so, leave, we'll get called again. This prevents us from trying
+         * to swallow too much data at once, or taking so long to write the data
+         * the client times out.
+         */
+        dobj->offset -= length;
+        if (dobj->offset <= 0) {
+            dobj->offset = 0;
+            break;
+        }
+        if ((dconf->readtime && apr_time_now() > dobj->timeout)) {
+            dobj->timeout = 0;
+            break;
+        }
+
+    }
+
+    /* Was this the final bucket? If yes, close the temp file and perform
+     * sanity checks.
+     */
+    if (seen_eos) {
+        if (!dobj->disk_info.header_only) {
+            const char *cl_header;
+            apr_off_t cl;
+
+            if (dobj->data.tempfd) {
+                rv = apr_file_close(dobj->data.tempfd);
+                if (rv != APR_SUCCESS) {
+                    /* Buffered write failed, abandon attempt to write */
+                    apr_pool_destroy(dobj->data.pool);
+                    return rv;
+                }
+            }
+
+            if (r->connection->aborted || r->no_cache) {
+                ap_log_rerror(
+                        APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(00733) "Discarding body for URL %s "
+                        "because connection has been aborted.", h->cache_obj->key);
+                /* Remove the intermediate cache file and return non-APR_SUCCESS */
+                apr_pool_destroy(dobj->data.pool);
+                return APR_EGENERAL;
+            }
+
+            if (dobj->file_size < dconf->minfs) {
+                ap_log_rerror(
+                        APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00734) "URL %s failed the size check "
+                        "(%" APR_OFF_T_FMT "<%" APR_OFF_T_FMT ")", h->cache_obj->key, dobj->file_size, dconf->minfs);
+                /* Remove the intermediate cache file and return non-APR_SUCCESS */
+                apr_pool_destroy(dobj->data.pool);
+                return APR_EGENERAL;
+            }
+
+            cl_header = apr_table_get(r->headers_out, "Content-Length");
+            if (cl_header && (!ap_parse_strict_length(&cl, cl_header)
+                              || cl != dobj->file_size)) {
+                ap_log_rerror(
+                        APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00735) "URL %s didn't receive complete response, not caching", h->cache_obj->key);
+                /* Remove the intermediate cache file and return non-APR_SUCCESS */
+                apr_pool_destroy(dobj->data.pool);
+                return APR_EGENERAL;
+            }
+        }
+
+        /* All checks were fine, we're good to go when the commit comes */
+    }
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t commit_entity(cache_handle_t *h, request_rec *r)
+{
+    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
+                                                 &cache_disk_module);
+    disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;
+    apr_status_t rv;
+
+    /* write the headers to disk at the last possible moment */
+    rv = write_headers(h, r);
+
+    /* move header and data tempfiles to the final destination */
+    if (APR_SUCCESS == rv) {
+        rv = file_cache_el_final(conf, &dobj->hdrs, r);
+    }
+    if (APR_SUCCESS == rv) {
+        rv = file_cache_el_final(conf, &dobj->vary, r);
+    }
+    if (APR_SUCCESS == rv) {
+        if (!dobj->disk_info.header_only) {
+            rv = file_cache_el_final(conf, &dobj->data, r);
+        }
+        else if (dobj->data.file) {
+            rv = apr_file_remove(dobj->data.file, dobj->data.pool);
+        }
+    }
+
+    /* remove the cached items completely on any failure */
+    if (APR_SUCCESS != rv) {
+        remove_url(h, r);
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00736)
+                "commit_entity: URL '%s' not cached due to earlier disk error.",
+                dobj->name);
+    }
+    else {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00737)
+                "commit_entity: Headers and body for URL %s cached.",
+                dobj->name);
+    }
+
+    apr_pool_destroy(dobj->data.pool);
+
+    return APR_SUCCESS;
+}
+
+static apr_status_t invalidate_entity(cache_handle_t *h, request_rec *r)
+{
+    apr_status_t rv;
+
+    rv = recall_headers(h, r);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+
+    /* mark the entity as invalidated */
+    h->cache_obj->info.control.invalidated = 1;
+
+    return commit_entity(h, r);
+}
+
+static void *create_dir_config(apr_pool_t *p, char *dummy)
+{
+    disk_cache_dir_conf *dconf = apr_pcalloc(p, sizeof(disk_cache_dir_conf));
+
+    dconf->maxfs = DEFAULT_MAX_FILE_SIZE;
+    dconf->minfs = DEFAULT_MIN_FILE_SIZE;
+    dconf->readsize = DEFAULT_READSIZE;
+    dconf->readtime = DEFAULT_READTIME;
+
+    return dconf;
+}
+
+static void *merge_dir_config(apr_pool_t *p, void *basev, void *addv)
+{
+    disk_cache_dir_conf *new = (disk_cache_dir_conf *) apr_pcalloc(p, sizeof(disk_cache_dir_conf));
+    disk_cache_dir_conf *add = (disk_cache_dir_conf *) addv;
+    disk_cache_dir_conf *base = (disk_cache_dir_conf *) basev;
+
+    new->maxfs = (add->maxfs_set == 0) ? base->maxfs : add->maxfs;
+    new->maxfs_set = add->maxfs_set || base->maxfs_set;
+    new->minfs = (add->minfs_set == 0) ? base->minfs : add->minfs;
+    new->minfs_set = add->minfs_set || base->minfs_set;
+    new->readsize = (add->readsize_set == 0) ? base->readsize : add->readsize;
+    new->readsize_set = add->readsize_set || base->readsize_set;
+    new->readtime = (add->readtime_set == 0) ? base->readtime : add->readtime;
+    new->readtime_set = add->readtime_set || base->readtime_set;
+
+    return new;
+}
+
+static void *create_config(apr_pool_t *p, server_rec *s)
+{
+    disk_cache_conf *conf = apr_pcalloc(p, sizeof(disk_cache_conf));
+
+    /* XXX: Set default values */
+    conf->dirlevels = DEFAULT_DIRLEVELS;
+    conf->dirlength = DEFAULT_DIRLENGTH;
+
+    conf->cache_root = NULL;
+    conf->cache_root_len = 0;
+
+    return conf;
+}
+
+/*
+ * mod_cache_disk configuration directives handlers.
+ */
+static const char
+*set_cache_root(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_conf *conf = ap_get_module_config(parms->server->module_config,
+                                                 &cache_disk_module);
+    conf->cache_root = arg;
+    conf->cache_root_len = strlen(arg);
+    /* TODO: canonicalize cache_root and strip off any trailing slashes */
+
+    return NULL;
+}
+
+/*
+ * Consider eliminating the next two directives in favor of
+ * Ian's prime number hash...
+ * key = hash_fn( r->uri)
+ * filename = "/key % prime1 /key %prime2/key %prime3"
+ */
+static const char
+*set_cache_dirlevels(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_conf *conf = ap_get_module_config(parms->server->module_config,
+                                                 &cache_disk_module);
+    int val = atoi(arg);
+    if (val < 1)
+        return "CacheDirLevels value must be an integer greater than 0";
+    if (val * conf->dirlength > CACHEFILE_LEN)
+        return "CacheDirLevels*CacheDirLength value must not be higher than 20";
+    conf->dirlevels = val;
+    return NULL;
+}
+static const char
+*set_cache_dirlength(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_conf *conf = ap_get_module_config(parms->server->module_config,
+                                                 &cache_disk_module);
+    int val = atoi(arg);
+    if (val < 1)
+        return "CacheDirLength value must be an integer greater than 0";
+    if (val * conf->dirlevels > CACHEFILE_LEN)
+        return "CacheDirLevels*CacheDirLength value must not be higher than 20";
+
+    conf->dirlength = val;
+    return NULL;
+}
+
+static const char
+*set_cache_minfs(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_dir_conf *dconf = (disk_cache_dir_conf *)in_struct_ptr;
+
+    if (apr_strtoff(&dconf->minfs, arg, NULL, 10) != APR_SUCCESS ||
+            dconf->minfs < 0)
+    {
+        return "CacheMinFileSize argument must be a non-negative integer representing the min size of a file to cache in bytes.";
+    }
+    dconf->minfs_set = 1;
+    return NULL;
+}
+
+static const char
+*set_cache_maxfs(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_dir_conf *dconf = (disk_cache_dir_conf *)in_struct_ptr;
+
+    if (apr_strtoff(&dconf->maxfs, arg, NULL, 10) != APR_SUCCESS ||
+            dconf->maxfs < 0)
+    {
+        return "CacheMaxFileSize argument must be a non-negative integer representing the max size of a file to cache in bytes.";
+    }
+    dconf->maxfs_set = 1;
+    return NULL;
+}
+
+static const char
+*set_cache_readsize(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_dir_conf *dconf = (disk_cache_dir_conf *)in_struct_ptr;
+
+    if (apr_strtoff(&dconf->readsize, arg, NULL, 10) != APR_SUCCESS ||
+            dconf->readsize < 0)
+    {
+        return "CacheReadSize argument must be a non-negative integer representing the max amount of data to cache in go.";
+    }
+    dconf->readsize_set = 1;
+    return NULL;
+}
+
+static const char
+*set_cache_readtime(cmd_parms *parms, void *in_struct_ptr, const char *arg)
+{
+    disk_cache_dir_conf *dconf = (disk_cache_dir_conf *)in_struct_ptr;
+    apr_off_t milliseconds;
+
+    if (apr_strtoff(&milliseconds, arg, NULL, 10) != APR_SUCCESS ||
+            milliseconds < 0)
+    {
+        return "CacheReadTime argument must be a non-negative integer representing the max amount of time taken to cache in go.";
+    }
+    dconf->readtime = apr_time_from_msec(milliseconds);
+    dconf->readtime_set = 1;
+    return NULL;
+}
+
+static const command_rec disk_cache_cmds[] =
+{
+    AP_INIT_TAKE1("CacheRoot", set_cache_root, NULL, RSRC_CONF,
+                 "The directory to store cache files"),
+    AP_INIT_TAKE1("CacheDirLevels", set_cache_dirlevels, NULL, RSRC_CONF,
+                  "The number of levels of subdirectories in the cache"),
+    AP_INIT_TAKE1("CacheDirLength", set_cache_dirlength, NULL, RSRC_CONF,
+                  "The number of characters in subdirectory names"),
+    AP_INIT_TAKE1("CacheMinFileSize", set_cache_minfs, NULL, RSRC_CONF | ACCESS_CONF,
+                  "The minimum file size to cache a document"),
+    AP_INIT_TAKE1("CacheMaxFileSize", set_cache_maxfs, NULL, RSRC_CONF | ACCESS_CONF,
+                  "The maximum file size to cache a document"),
+    AP_INIT_TAKE1("CacheReadSize", set_cache_readsize, NULL, RSRC_CONF | ACCESS_CONF,
+                  "The maximum quantity of data to attempt to read and cache in one go"),
+    AP_INIT_TAKE1("CacheReadTime", set_cache_readtime, NULL, RSRC_CONF | ACCESS_CONF,
+                  "The maximum time taken to attempt to read and cache in go"),
+    {NULL}
+};
+
+static const cache_provider cache_disk_provider =
+{
+    &remove_entity,
+    &store_headers,
+    &store_body,
+    &recall_headers,
+    &recall_body,
+    &create_entity,
+    &open_entity,
+    &remove_url,
+    &commit_entity,
+    &invalidate_entity
+};
+
+static void disk_cache_register_hook(apr_pool_t *p)
+{
+    /* cache initializer */
+    ap_register_provider(p, CACHE_PROVIDER_GROUP, "disk", "0",
+                         &cache_disk_provider);
+}
+
+AP_DECLARE_MODULE(cache_disk) = {
+    STANDARD20_MODULE_STUFF,
+    create_dir_config,          /* create per-directory config structure */
+    merge_dir_config,           /* merge per-directory config structures */
+    create_config,              /* create per-server config structure */
+    NULL,                       /* merge per-server config structures */
+    disk_cache_cmds,            /* command apr_table_t */
+    disk_cache_register_hook    /* register hooks */
+};