/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright (C) 2001 Red Hat, Inc. * * Created by Arjan van de Ven <arjanv@redhat.com> * * The original JFFS, from which the design for JFFS2 was derived, * was designed and implemented by Axis Communications AB. * * The contents of this file are subject to the Red Hat eCos Public * License Version 1.1 (the "Licence"); you may not use this file * except in compliance with the Licence.  You may obtain a copy of * the Licence at http://www.redhat.com/ * * Software distributed under the Licence is distributed on an "AS IS" * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. * See the Licence for the specific language governing rights and * limitations under the Licence. * * The Original Code is JFFS2 - Journalling Flash File System, version 2 * * Alternatively, the contents of this file may be used under the * terms of the GNU General Public License version 2 (the "GPL"), in * which case the provisions of the GPL are applicable instead of the * above.  If you wish to allow the use of your version of this file * only under the terms of the GPL and not to allow others to use your * version of this file under the RHEPL, indicate your decision by * deleting the provisions above and replace them with the notice and * other provisions required by the GPL.  If you do not delete the * provisions above, a recipient may use your version of this file * under either the RHEPL or the GPL. * * * Very simple lz77-ish encoder. * * Theory of operation: Both encoder and decoder have a list of "last * occurances" for every possible source-value; after sending the * first source-byte, the second byte indicated the "run" length of * matches * * The algorithm is intended to only send "whole bytes", no bit-messing. * */#include <config.h>#if (CONFIG_COMMANDS & CFG_CMD_JFFS2)#include <armboot.h>#include <types.h>#include <jffs2/jffs2.h>void rtime_decompress(unsigned char *data_in, unsigned char *cpage_out,		      u32 srclen, u32 destlen){	int positions[256];	int outpos;	int pos;	int i;	outpos = pos = 0;	for (i = 0; i < 256; positions[i++] = 0);	while (outpos<destlen) {		unsigned char value;		int backoffs;		int repeat;		value = data_in[pos++];		cpage_out[outpos++] = value; /* first the verbatim copied byte */		repeat = data_in[pos++];		backoffs = positions[value];		positions[value]=outpos;		if (repeat) {			if (backoffs + repeat >= outpos) {				while(repeat) {					cpage_out[outpos++] = cpage_out[backoffs++];					repeat--;				}			} else {				for (i = 0; i < repeat; i++)					*(cpage_out + outpos + i) = *(cpage_out + backoffs + i);				outpos+=repeat;			}		}	}}#endif /* CFG_CMD_JFFS2 */