Hi guys.
in an effort to avoid doing real-work,
I wrote a GZip compression filter which I
think should go into the standard apache distribution.
I haven't done too much hammering on it, but it seems to work with
IE and NS6 and NS4.
oh.. I've never done autoconf stuff before.. it kinda works but it
should enable --with-z when a --enable-gz is set.
..Ian
--
Ian Holsman [EMAIL PROTECTED]
Performance Measurement & Analysis
CNET Networks - (415) 364-8608
# a modules Makefile has no explicit targets -- they will be defined by
# whatever modules are enabled. just grab special.mk to deal with this.
include $(top_srcdir)/build/special.mk
APACHE_MODPATH_INIT(gz)
APACHE_MODULE(gz, GZip encoding support, "mod_gz.lo", , no, [
AC_MSG_CHECKING(for Zlib library)
AC_ARG_WITH(z, [ --with-z=DIR use a specific zlib library],
[
if test x"$withval" = x"yes"; then
for dir in /usr /usr/local/
do
if test -d $dir && test -f $dir/lib/libz.a; then
withval=$dir
break
fi
done
if test x"$withval" = x"yes"; then
AC_MSG_ERROR(Use --with-z=DIR to specify the location of your Zlib
installation)
fi
fi
z_lib=unknown
for params in \
"zlib|/include/|/lib|-lz "
do
prod=`IFS="|"; set -- $params; echo $1`
incdir=`IFS="|"; set -- $params; echo $2`
libdir=`IFS="|"; set -- $params; echo $3`
libs=`IFS="|"; set -- $params; echo $4`
searchfile="${withval}${incdir}/zlib.h"
if test -f ${searchfile} ; then
APR_ADDTO(INCLUDES, [-I${withval}${incdir}])
APR_ADDTO(LIBS, [-L${withval}${libdir} ${libs}])
z_lib="${prod}"
break
fi
done
if test x"${z_lib}" = x"unknown"; then
AC_MSG_ERROR(--with-z given but no appropriate lib found)
else
AC_MSG_RESULT(found $z_lib)
fi
],[
AC_MSG_ERROR(--with-z not given)
] ) ] )
APACHE_MODPATH_FINISH
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact [EMAIL PROTECTED]
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* Portions of this software are based upon public domain software
* (zlib functions gz_open and gzwrite)
*/
/*
* mod_gz.c: GZip's HTML content on the fly
*
* Written by Ian Holsman ([EMAIL PROTECTED])
*
*/
#include "zlib.h"
#include "zutil.h"
#include "httpd.h"
#include "http_config.h"
#include "http_log.h"
#include "apr_strings.h"
#include "apr_general.h"
#include "util_filter.h"
#include "apr_buckets.h"
#include "http_request.h"
static const char s_szGZFilterName[] = "GZ";
module AP_MODULE_DECLARE_DATA gz_module;
typedef struct
{
int bEnabled;
}
GZFilterConfig;
#define GZFILTER_WINDOWSIZE -15 /* windowsize is negative to suppress Zlib header */
#define GZFILTER_MEMLEVEL 9
#define GZFILTER_BUFFERSIZE 8096
typedef struct gz_ctx
{
z_stream strm;
char buffer[GZFILTER_BUFFERSIZE];
unsigned long crc;
}
gz_ctx;
/* ===========================================================================
Outputs a long in LSB order to the given file
*/
local void putLong(char *string, unsigned long x)
{
int n;
for (n = 0; n < 4; n++) {
string[n] = (int) (x & 0xff);
x >>= 8;
}
}
static void *GZFilterCreateServerConfig(apr_pool_t * p, server_rec * s)
{
GZFilterConfig *pConfig = apr_pcalloc(p, sizeof *pConfig);
pConfig->bEnabled = 0;
return pConfig;
}
static const char *GZFilterEnable(cmd_parms * cmd, void *dummy, int arg)
{
GZFilterConfig *pConfig = ap_get_module_config(cmd->server->module_config,
&gz_module);
pConfig->bEnabled = arg;
return NULL;
}
static void GZFilterInsertFilter(request_rec * r)
{
GZFilterConfig *pConfig = ap_get_module_config(r->server->module_config,
&gz_module);
if (!pConfig->bEnabled)
return;
ap_add_output_filter(s_szGZFilterName, NULL, r, r->connection);
}
static int gz_magic[2] = { 0x1f, 0x8b }; /* gzip magic header */
static apr_status_t GZFilterOutFilter(ap_filter_t * f,
apr_bucket_brigade * pbbIn)
{
apr_bucket *pbktIn;
apr_bucket_brigade *pbbOut;
apr_bucket *pbktOut;
char *buf;
const char *accepts;
request_rec *r = f->r;
gz_ctx *ctx;
char *token = NULL;
char *state = NULL;
int zRC;
/* only compress text/html files */
if (strncmp(r->content_type, "text/html", 9))
return ap_pass_brigade(f->next, pbbIn);
/* GETs only (for the moment) */
if (r->method_number != M_GET) {
return ap_pass_brigade(f->next, pbbIn);
}
/* some browsers might have problems, so set no-gzip (with browsermatch) for them */
if (apr_table_get(r->subprocess_env, "no-gzip")) {
return ap_pass_brigade(f->next, pbbIn);
}
accepts = apr_table_get(r->headers_in, "Accept-Encoding");
/* if they don't have the line, then they can't play */
if (accepts == NULL) {
return ap_pass_brigade(f->next, pbbIn);
}
token = ap_get_token(r->pool, &accepts, 0);
while (token && token[0] && strcmp(token, "gzip")) {
accepts++; /* skip token */
token = ap_get_token(r->pool, &accepts, 0);
}
if (token == NULL || token[0] == '\0') {
return ap_pass_brigade(f->next, pbbIn);
}
pbbOut = apr_brigade_create(f->r->pool);
if (!f->ctx) {
f->ctx = apr_pcalloc(f->c->pool, sizeof(*ctx));
ctx = f->ctx;
ctx->strm.zalloc = (alloc_func) 0;
ctx->strm.zfree = (free_func) 0;
ctx->strm.opaque = (voidpf) 0;
ctx->crc = 0L;
zRC = deflateInit2(&ctx->strm, Z_BEST_SPEED, Z_DEFLATED,
GZFILTER_WINDOWSIZE, GZFILTER_MEMLEVEL,
Z_DEFAULT_STRATEGY);
if (zRC != Z_OK) {
f->ctx = NULL;
ap_log_rerror(APLOG_MARK, APLOG_ERR | APLOG_NOERRNO, 0, r,
"unable to init Zlib: deflateInit2 returned %d: URL %s",
zRC, r->uri);
return ap_pass_brigade(f->next, pbbIn);
}
buf =
apr_psprintf(r->pool, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0],
gz_magic[1], Z_DEFLATED, 0 /*flags */ , 0, 0, 0,
0 /*time */ , 0 /*xflags */ , OS_CODE);
pbktOut = apr_bucket_pool_create(buf, 10, r->pool);
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktOut);
apr_table_setn(r->headers_out, "Content-Encoding", "gzip");
apr_table_setn(r->headers_out, "Vary", "Accept-Encoding");
}
else {
ctx = f->ctx;
}
APR_BRIGADE_FOREACH(pbktIn, pbbIn) {
const char *data;
apr_size_t lenin;
unsigned int len;
char *buf;
char szCRC[4];
char szLen[4];
apr_size_t e_wrt;
int done = 0;
if (APR_BUCKET_IS_EOS(pbktIn)) {
apr_bucket *pbktEOS = apr_bucket_eos_create();
ctx->strm.avail_in = 0; /* should be zero already anyway */
for (;;) {
len = GZFILTER_BUFFERSIZE - ctx->strm.avail_out;
if (len != 0) {
pbktOut =
apr_bucket_heap_create(ctx->buffer, len, 1, &e_wrt);
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktOut);
ctx->strm.next_out = ctx->buffer;
ctx->strm.avail_out = GZFILTER_BUFFERSIZE;
}
if (done)
break;
zRC = deflate(&ctx->strm, Z_FINISH);
if (len == 0 && zRC == Z_BUF_ERROR)
zRC = Z_OK;
done = (ctx->strm.avail_out != 0 || zRC == Z_STREAM_END);
if (zRC != Z_OK && zRC != Z_STREAM_END)
break;
}
putLong(szCRC, ctx->crc);
putLong(szLen, ctx->strm.total_in);
buf =
apr_psprintf(r->pool, "%c%c%c%c%c%c%c%c", szCRC[0], szCRC[1],
szCRC[2], szCRC[3], szLen[0], szLen[1], szLen[2],
szLen[3]);
pbktOut = apr_bucket_pool_create(buf, 8, r->pool);
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktOut);
ap_log_rerror(APLOG_MARK, APLOG_DEBUG | APLOG_NOERRNO, 0, r,
"Zlib: Compressed %d to %d : URL %s",
ctx->strm.total_in, ctx->strm.total_out, r->uri);
deflateEnd(&ctx->strm);
f->ctx = NULL;
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktOut);
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktEOS);
break;
}
if (APR_BUCKET_IS_FLUSH(pbktIn)) {
/* XXX FIX: do we need the Content-Size set, or can we stream? we should be able to stream */
/* ignore flush buckets for the moment.. we can't stream as we need the size ;( */
continue;
}
/* read */
apr_bucket_read(pbktIn, &data, &lenin, APR_BLOCK_READ);
ctx->crc = crc32(ctx->crc, (const Bytef *) data, lenin);
/* write */
ctx->strm.next_in = (char *) data;
ctx->strm.avail_in = lenin;
ctx->strm.next_out = ctx->buffer;
ctx->strm.avail_out = GZFILTER_BUFFERSIZE;
while (ctx->strm.avail_in != 0) {
if (ctx->strm.avail_out == 0) {
ctx->strm.next_out = ctx->buffer;
len = GZFILTER_BUFFERSIZE - ctx->strm.avail_out;
pbktOut = apr_bucket_heap_create(ctx->buffer, len, 1, &e_wrt);
APR_BRIGADE_INSERT_TAIL(pbbOut, pbktOut);
ctx->strm.avail_out = GZFILTER_BUFFERSIZE;
}
zRC = deflate(&(ctx->strm), Z_NO_FLUSH);
if (zRC != Z_OK)
break;
}
}
return ap_pass_brigade(f->next, pbbOut);
}
static void GZFilterRegisterHooks(apr_pool_t * p)
{
ap_hook_insert_filter(GZFilterInsertFilter, NULL, NULL, APR_HOOK_MIDDLE);
ap_register_output_filter(s_szGZFilterName, GZFilterOutFilter,
AP_FTYPE_CONTENT);
}
static const command_rec GZFilterCmds[] = {
AP_INIT_FLAG("GZFilter", GZFilterEnable, NULL, RSRC_CONF,
"Run a GZ filter on this host"),
{NULL}
};
module AP_MODULE_DECLARE_DATA gz_module = {
STANDARD20_MODULE_STUFF,
NULL,
NULL,
GZFilterCreateServerConfig,
NULL,
GZFilterCmds,
GZFilterRegisterHooks
};
