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-rw-r--r--compr_rtime.c119
1 files changed, 0 insertions, 119 deletions
diff --git a/compr_rtime.c b/compr_rtime.c
deleted file mode 100644
index f24379d..0000000
--- a/compr_rtime.c
+++ /dev/null
@@ -1,119 +0,0 @@
-/*
- * JFFS2 -- Journalling Flash File System, Version 2.
- *
- * Copyright (C) 2001-2003 Red Hat, Inc.
- *
- * Created by Arjan van de Ven <arjanv@redhat.com>
- *
- * For licensing information, see the file 'LICENCE' in this directory.
- *
- * Very simple lz77-ish encoder.
- *
- * Theory of operation: Both encoder and decoder have a list of "last
- * occurrences" 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 <stdint.h>
-#include <string.h>
-#include "compr.h"
-
-/* _compress returns the compressed size, -1 if bigger */
-static int jffs2_rtime_compress(unsigned char *data_in, unsigned char *cpage_out,
- uint32_t *sourcelen, uint32_t *dstlen)
-{
- short positions[256];
- int outpos = 0;
- int pos=0;
-
- memset(positions,0,sizeof(positions));
-
- while (pos < (*sourcelen) && outpos+2 <= (*dstlen)) {
- int backpos, runlen=0;
- unsigned char value;
-
- value = data_in[pos];
-
- cpage_out[outpos++] = data_in[pos++];
-
- backpos = positions[value];
- positions[value]=pos;
-
- while ((backpos < pos) && (pos < (*sourcelen)) &&
- (data_in[pos]==data_in[backpos++]) && (runlen<255)) {
- pos++;
- runlen++;
- }
- cpage_out[outpos++] = runlen;
- }
-
- if (outpos >= pos) {
- /* We failed */
- return -1;
- }
-
- /* Tell the caller how much we managed to compress, and how much space it took */
- *sourcelen = pos;
- *dstlen = outpos;
- return 0;
-}
-
-
-static int jffs2_rtime_decompress(unsigned char *data_in, unsigned char *cpage_out,
- __attribute__((unused)) uint32_t srclen, uint32_t destlen)
-{
- short positions[256];
- int outpos = 0;
- int pos=0;
-
- memset(positions,0,sizeof(positions));
-
- 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 {
- memcpy(&cpage_out[outpos],&cpage_out[backoffs],repeat);
- outpos+=repeat;
- }
- }
- }
- return 0;
-}
-
-
-static struct jffs2_compressor jffs2_rtime_comp = {
- .priority = JFFS2_RTIME_PRIORITY,
- .name = "rtime",
- .disabled = 0,
- .compr = JFFS2_COMPR_RTIME,
- .compress = &jffs2_rtime_compress,
- .decompress = &jffs2_rtime_decompress,
-};
-
-int jffs2_rtime_init(void)
-{
- return jffs2_register_compressor(&jffs2_rtime_comp);
-}
-
-void jffs2_rtime_exit(void)
-{
- jffs2_unregister_compressor(&jffs2_rtime_comp);
-}