Zip: add a stream_filter and an access

The stream_filter does the following job:
[zip stream] -->filter--> [xspf playlist]

The access is called zip or unzip and takes MRLs of the form:
zip://[web-encoded-path]![file-in-zip]

As there is some automatic web-form decoding of the MRL,
the MRLs in the playlist generated by zipstream are encoded
two times.

modules/access/zip/Modules.am

+if HAVE_ZLIB
+SOURCES_zip = \
+	zipstream.c \
+	zipaccess.c \
+	$(NULL)
+endif

modules/access/zip/zip.h

+/*****************************************************************************
+ * zip.h: Module (access+demux) to extract different archives, based on zlib
+ *****************************************************************************
+ * Copyright (C) 2007 the VideoLAN team
+ * $Id$
+ *
+ * Authors: Jean-Philippe André <jpeg@videolan.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+/** **************************************************************************
+ * Common includes and shared headers
+ *****************************************************************************/
+
+#ifndef ZIP_ACCESSDEMUX_H
+#define ZIP_ACCESSDEMUX_H
+
+#include <vlc/vlc.h>
+#include <vlc_common.h>
+#include <vlc_url.h>
+#include <vlc_strings.h>
+#include <vlc_arrays.h>
+#include <vlc_plugin.h>
+#include <vlc_stream.h>
+#include "unzip.h"
+#include "ioapi.h"
+
+#include <assert.h>
+
+#define ZIP_FILENAME_LEN 512
+#define ZIP_BUFFER_LEN 32768
+#define ZIP_SEP      "|"
+#define ZIP_SEP_CHAR '|'
+
+
+/** **************************************************************************
+ * Module access points: stream_filter
+ *****************************************************************************/
+int StreamOpen( vlc_object_t* );
+void StreamClose( vlc_object_t* );
+
+/** **************************************************************************
+ * Module access points: access
+ *****************************************************************************/
+int AccessOpen( vlc_object_t *p_this );
+void AccessClose( vlc_object_t *p_this );
+
+/** **************************************************************************
+ * zipIO function headers : how to use vlc_stream to read the zip
+ * Note: static because the implementations differ
+ *****************************************************************************/
+static void* ZCALLBACK ZipIO_Open( void* opaque, const char* filename, int m );
+static uLong ZCALLBACK ZipIO_Read( void*, void* stream, void* buf, uLong sz );
+static uLong ZCALLBACK ZipIO_Write( void*, void* stream, const void*, uLong );
+static long ZCALLBACK ZipIO_Tell( void*, void* stream );
+static long ZCALLBACK ZipIO_Seek( void*, void* stream, uLong offset, int ori );
+static int ZCALLBACK ZipIO_Close( void*, void* stream );
+static int ZCALLBACK ZipIO_Error( void*, void* stream );
+
+#endif /* ZIP_ACCESSDEMUX_H */