mod_disk_cache.c revision 6d14bedccc13d7a5f95fb9328eb6d1a07b58731b
/* 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_disk_cache.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_disk_cache: 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 disk_cache_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_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: 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;
disk_cache_info_t disk_info;
apr_size_t len;
/* read the data from the cache file */
len = sizeof(disk_cache_info_t);
rv = apr_file_read_full(fd, &disk_info, len, &len);
if (rv != APR_SUCCESS) {
return rv;
}
/* Store it away so we can get it later. */
dobj->disk_info = disk_info;
info->status = disk_info.status;
info->date = disk_info.date;
info->expire = disk_info.expire;
info->request_time = disk_info.request_time;
info->response_time = disk_info.response_time;
/* Note that we could optimize this by conditionally doing the palloc
* depending upon the size. */
urlbuff = apr_palloc(r->pool, disk_info.name_len + 1);
len = disk_info.name_len;
rv = apr_file_read_full(fd, urlbuff, len, &len);
if (rv != APR_SUCCESS) {
return rv;
}
urlbuff[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 [exerpt]
* 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 [exerpt]
* 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_conf *conf = ap_get_module_config(r->server->module_config,
&disk_cache_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_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: 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 > conf->maxfs) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: URL %s failed the size check "
"(%" APR_OFF_T_FMT " > %" APR_OFF_T_FMT ")",
key, len, conf->maxfs);
return DECLINED;
}
if (len >= 0 && len < conf->minfs) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: URL %s failed the size check "
"(%" APR_OFF_T_FMT " < %" APR_OFF_T_FMT ")",
key, len, conf->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_pstrndup(r->pool, conf->cache_root, conf->cache_root_len);
dobj->root_len = conf->cache_root_len;
apr_pool_create(&pool, r->pool);
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);
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,
&disk_cache_module);
#ifdef APR_SENDFILE_ENABLED
core_dir_config *coreconf = ap_get_module_config(r->per_dir_config,
&core_module);
#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_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"disk_cache: Cannot cache files to disk without a CacheRoot specified.");
}
return DECLINED;
}
/* Create and init the cache object */
h->cache_obj = obj = apr_pcalloc(r->pool, sizeof(cache_object_t));
obj->vobj = 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_pstrndup(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_error(APLOG_MARK, APLOG_ERR, rc, r->server,
"disk_cache: 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_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"disk_cache: 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);
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);
/* Open the data file */
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_error(APLOG_MARK, APLOG_ERR, rc, r->server,
"disk_cache: 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, dobj->data.fd);
if (rc == APR_SUCCESS) {
dobj->file_size = finfo.size;
}
/* 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_error(APLOG_MARK, APLOG_ERR, rc, r->server,
"disk_cache: Cannot read header file %s", dobj->hdrs.file);
apr_file_close(dobj->hdrs.fd);
return DECLINED;
}
/* Initialize the cache_handle callback functions */
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: Recalled cached URL info header %s", dobj->name);
apr_file_close(dobj->hdrs.fd);
return OK;
}
static int remove_entity(cache_handle_t *h)
{
/* 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, apr_pool_t *p)
{
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_error(APLOG_MARK, APLOG_DEBUG, 0, NULL,
"disk_cache: Deleting %s from cache.", dobj->hdrs.file);
rc = apr_file_remove(dobj->hdrs.file, p);
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_error(APLOG_MARK, APLOG_DEBUG, rc, NULL,
"disk_cache: Failed to delete headers file %s from cache.",
dobj->hdrs.file);
return DECLINED;
}
}
/* Delete data file */
if (dobj->data.file) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL,
"disk_cache: Deleting %s from cache.", dobj->data.file);
rc = apr_file_remove(dobj->data.file, p);
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_error(APLOG_MARK, APLOG_DEBUG, rc, NULL,
"disk_cache: 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(p, 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_error(APLOG_MARK, APLOG_DEBUG, 0, NULL,
"disk_cache: Deleting directory %s from cache",
dir);
rc = apr_dir_remove(dir, p);
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];
int 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,
"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(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(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;
int 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, 0, r,
"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_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"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 (*l && 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;
/* This case should not happen... */
if (!dobj->hdrs.fd) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"disk_cache: 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 */
read_table(h, r, h->resp_hdrs, dobj->hdrs.fd);
read_table(h, r, h->req_hdrs, dobj->hdrs.fd);
apr_file_close(dobj->hdrs.fd);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: 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)
{
apr_bucket *e;
disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;
apr_brigade_insert_file(bb, dobj->data.fd, 0, dobj->file_size, p);
e = apr_bucket_eos_create(bb->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
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(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(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_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->hdrs.file = dobj->prefix;
dobj->prefix = NULL;
}
rv = mkdir_structure(conf, dobj->hdrs.file, r->pool);
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_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: could not create temp file %s",
dobj->vary.tempfile);
return rv;
}
amt = sizeof(format);
apr_file_write(dobj->vary.tempfd, &format, &amt);
amt = sizeof(info->expire);
apr_file_write(dobj->vary.tempfd, &info->expire, &amt);
varray = apr_array_make(r->pool, 6, sizeof(char*));
tokens_to_array(r->pool, tmp, varray);
store_array(dobj->vary.tempfd, varray);
apr_file_close(dobj->vary.tempfd);
tmp = regen_key(r->pool, r->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_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: could not create temp file %s",
dobj->hdrs.tempfile);
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->hdrs.tempfd, (const struct iovec *) &iov, 2, &amt);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: could not write info to header file %s",
dobj->hdrs.tempfile);
apr_file_close(dobj->hdrs.tempfd);
return rv;
}
if (r->headers_out) {
apr_table_t *headers_out;
headers_out = ap_cache_cacheable_headers_out(r);
rv = store_table(dobj->hdrs.tempfd, headers_out);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: could not write out-headers to header file %s",
dobj->hdrs.tempfile);
apr_file_close(dobj->hdrs.tempfd);
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_headers_in(r);
rv = store_table(dobj->hdrs.tempfd, headers_in);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_WARNING, rv, r->server,
"disk_cache: could not write in-headers to header file %s",
dobj->hdrs.tempfile);
apr_file_close(dobj->hdrs.tempfd);
return rv;
}
}
apr_file_close(dobj->hdrs.tempfd); /* flush and close */
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_conf *conf = ap_get_module_config(r->server->module_config,
&disk_cache_module);
disk_cache_dir_conf *dconf = ap_get_module_config(r->per_dir_config, &disk_cache_module);
int seen_eos = 0;
/* We write to a temp file and then atomically rename the file over
* in file_cache_el_final().
*/
if (!dobj->data.tempfd) {
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) {
return rv;
}
dobj->file_size = 0;
}
if (!dobj->bb) {
dobj->bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
}
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) {
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_CONCAT(out, dobj->bb);
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_CONCAT(out, dobj->bb);
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(dobj->bb, 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(dobj->bb, e);
if (rv != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"disk_cache: 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);
APR_BRIGADE_CONCAT(out, dobj->bb);
return rv;
}
/* 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_error(APLOG_MARK, APLOG_ERR, 0, r->server,
"disk_cache: 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);
APR_BRIGADE_CONCAT(out, dobj->bb);
return rv;
}
dobj->file_size += written;
if (dobj->file_size > conf->maxfs) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: URL %s failed the size check "
"(%" APR_OFF_T_FMT ">%" APR_OFF_T_FMT ")",
h->cache_obj->key, dobj->file_size, conf->maxfs);
/* Remove the intermediate cache file and return non-APR_SUCCESS */
apr_pool_destroy(dobj->data.pool);
APR_BRIGADE_CONCAT(out, dobj->bb);
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;
APR_BRIGADE_CONCAT(out, dobj->bb);
break;
}
if ((dconf->readtime && apr_time_now() > dobj->timeout)) {
dobj->timeout = 0;
APR_BRIGADE_CONCAT(out, dobj->bb);
break;
}
}
/* Was this the final bucket? If yes, close the temp file and perform
* sanity checks.
*/
if (seen_eos) {
const char *cl_header = apr_table_get(r->headers_out, "Content-Length");
apr_file_close(dobj->data.tempfd);
if (r->connection->aborted || r->no_cache) {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"disk_cache: 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 < conf->minfs) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: URL %s failed the size check "
"(%" APR_OFF_T_FMT "<%" APR_OFF_T_FMT ")",
h->cache_obj->key, dobj->file_size, conf->minfs);
/* Remove the intermediate cache file and return non-APR_SUCCESS */
apr_pool_destroy(dobj->data.pool);
return APR_EGENERAL;
}
if (cl_header) {
apr_int64_t cl = apr_atoi64(cl_header);
if ((errno == 0) && (dobj->file_size != cl)) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: 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,
&disk_cache_module);
disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;
apr_status_t rv;
/* move header and data tempfiles to the final destination */
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) {
rv = file_cache_el_final(conf, &dobj->data, r);
}
/* remove the cached items completely on any failure */
if (APR_SUCCESS != rv) {
remove_url(h, r->pool);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: commit_entity: URL '%s' not cached due to earlier disk error.",
dobj->name);
}
else {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"disk_cache: commit_entity: Headers and body for URL %s cached.",
dobj->name);
}
apr_pool_destroy(dobj->data.pool);
return APR_SUCCESS;
}
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->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->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->maxfs = DEFAULT_MAX_FILE_SIZE;
conf->minfs = DEFAULT_MIN_FILE_SIZE;
conf->cache_root = NULL;
conf->cache_root_len = 0;
return conf;
}
/*
* mod_disk_cache 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,
&disk_cache_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,
&disk_cache_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,
&disk_cache_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_conf *conf = ap_get_module_config(parms->server->module_config,
&disk_cache_module);
if (apr_strtoff(&conf->minfs, arg, NULL, 0) != APR_SUCCESS ||
conf->minfs < 0)
{
return "CacheMinFileSize argument must be a non-negative integer representing the min size of a file to cache in bytes.";
}
return NULL;
}
static const char
*set_cache_maxfs(cmd_parms *parms, void *in_struct_ptr, const char *arg)
{
disk_cache_conf *conf = ap_get_module_config(parms->server->module_config,
&disk_cache_module);
if (apr_strtoff(&conf->maxfs, arg, NULL, 0) != APR_SUCCESS ||
conf->maxfs < 0)
{
return "CacheMaxFileSize argument must be a non-negative integer representing the max size of a file to cache in bytes.";
}
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, 0) != 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, 0) != 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,
"The minimum file size to cache a document"),
AP_INIT_TAKE1("CacheMaxFileSize", set_cache_maxfs, NULL, RSRC_CONF,
"The maximum file size to cache a document"),
AP_INIT_TAKE1("CacheReadSize", set_cache_readsize, NULL, RSRC_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,
"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
};
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(disk_cache) = {
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 */
};