Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/jffs2/compr_rubin.c b/fs/jffs2/compr_rubin.c
new file mode 100644
index 0000000..450d662
--- /dev/null
+++ b/fs/jffs2/compr_rubin.c
@@ -0,0 +1,373 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2001, 2002 Red Hat, Inc.
+ *
+ * Created by Arjan van de Ven <arjanv@redhat.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: compr_rubin.c,v 1.20 2004/06/23 16:34:40 havasi Exp $
+ *
+ */
+
+
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/jffs2.h>
+#include "compr_rubin.h"
+#include "histo_mips.h"
+#include "compr.h"
+
+static void init_rubin(struct rubin_state *rs, int div, int *bits)
+{
+ int c;
+
+ rs->q = 0;
+ rs->p = (long) (2 * UPPER_BIT_RUBIN);
+ rs->bit_number = (long) 0;
+ rs->bit_divider = div;
+ for (c=0; c<8; c++)
+ rs->bits[c] = bits[c];
+}
+
+
+static int encode(struct rubin_state *rs, long A, long B, int symbol)
+{
+
+ long i0, i1;
+ int ret;
+
+ while ((rs->q >= UPPER_BIT_RUBIN) || ((rs->p + rs->q) <= UPPER_BIT_RUBIN)) {
+ rs->bit_number++;
+
+ ret = pushbit(&rs->pp, (rs->q & UPPER_BIT_RUBIN) ? 1 : 0, 0);
+ if (ret)
+ return ret;
+ rs->q &= LOWER_BITS_RUBIN;
+ rs->q <<= 1;
+ rs->p <<= 1;
+ }
+ i0 = A * rs->p / (A + B);
+ if (i0 <= 0) {
+ i0 = 1;
+ }
+ if (i0 >= rs->p) {
+ i0 = rs->p - 1;
+ }
+ i1 = rs->p - i0;
+
+ if (symbol == 0)
+ rs->p = i0;
+ else {
+ rs->p = i1;
+ rs->q += i0;
+ }
+ return 0;
+}
+
+
+static void end_rubin(struct rubin_state *rs)
+{
+
+ int i;
+
+ for (i = 0; i < RUBIN_REG_SIZE; i++) {
+ pushbit(&rs->pp, (UPPER_BIT_RUBIN & rs->q) ? 1 : 0, 1);
+ rs->q &= LOWER_BITS_RUBIN;
+ rs->q <<= 1;
+ }
+}
+
+
+static void init_decode(struct rubin_state *rs, int div, int *bits)
+{
+ init_rubin(rs, div, bits);
+
+ /* behalve lower */
+ rs->rec_q = 0;
+
+ for (rs->bit_number = 0; rs->bit_number++ < RUBIN_REG_SIZE; rs->rec_q = rs->rec_q * 2 + (long) (pullbit(&rs->pp)))
+ ;
+}
+
+static void __do_decode(struct rubin_state *rs, unsigned long p, unsigned long q)
+{
+ register unsigned long lower_bits_rubin = LOWER_BITS_RUBIN;
+ unsigned long rec_q;
+ int c, bits = 0;
+
+ /*
+ * First, work out how many bits we need from the input stream.
+ * Note that we have already done the initial check on this
+ * loop prior to calling this function.
+ */
+ do {
+ bits++;
+ q &= lower_bits_rubin;
+ q <<= 1;
+ p <<= 1;
+ } while ((q >= UPPER_BIT_RUBIN) || ((p + q) <= UPPER_BIT_RUBIN));
+
+ rs->p = p;
+ rs->q = q;
+
+ rs->bit_number += bits;
+
+ /*
+ * Now get the bits. We really want this to be "get n bits".
+ */
+ rec_q = rs->rec_q;
+ do {
+ c = pullbit(&rs->pp);
+ rec_q &= lower_bits_rubin;
+ rec_q <<= 1;
+ rec_q += c;
+ } while (--bits);
+ rs->rec_q = rec_q;
+}
+
+static int decode(struct rubin_state *rs, long A, long B)
+{
+ unsigned long p = rs->p, q = rs->q;
+ long i0, threshold;
+ int symbol;
+
+ if (q >= UPPER_BIT_RUBIN || ((p + q) <= UPPER_BIT_RUBIN))
+ __do_decode(rs, p, q);
+
+ i0 = A * rs->p / (A + B);
+ if (i0 <= 0) {
+ i0 = 1;
+ }
+ if (i0 >= rs->p) {
+ i0 = rs->p - 1;
+ }
+
+ threshold = rs->q + i0;
+ symbol = rs->rec_q >= threshold;
+ if (rs->rec_q >= threshold) {
+ rs->q += i0;
+ i0 = rs->p - i0;
+ }
+
+ rs->p = i0;
+
+ return symbol;
+}
+
+
+
+static int out_byte(struct rubin_state *rs, unsigned char byte)
+{
+ int i, ret;
+ struct rubin_state rs_copy;
+ rs_copy = *rs;
+
+ for (i=0;i<8;i++) {
+ ret = encode(rs, rs->bit_divider-rs->bits[i],rs->bits[i],byte&1);
+ if (ret) {
+ /* Failed. Restore old state */
+ *rs = rs_copy;
+ return ret;
+ }
+ byte=byte>>1;
+ }
+ return 0;
+}
+
+static int in_byte(struct rubin_state *rs)
+{
+ int i, result = 0, bit_divider = rs->bit_divider;
+
+ for (i = 0; i < 8; i++)
+ result |= decode(rs, bit_divider - rs->bits[i], rs->bits[i]) << i;
+
+ return result;
+}
+
+
+
+static int rubin_do_compress(int bit_divider, int *bits, unsigned char *data_in,
+ unsigned char *cpage_out, uint32_t *sourcelen, uint32_t *dstlen)
+ {
+ int outpos = 0;
+ int pos=0;
+ struct rubin_state rs;
+
+ init_pushpull(&rs.pp, cpage_out, *dstlen * 8, 0, 32);
+
+ init_rubin(&rs, bit_divider, bits);
+
+ while (pos < (*sourcelen) && !out_byte(&rs, data_in[pos]))
+ pos++;
+
+ end_rubin(&rs);
+
+ if (outpos > pos) {
+ /* We failed */
+ return -1;
+ }
+
+ /* Tell the caller how much we managed to compress,
+ * and how much space it took */
+
+ outpos = (pushedbits(&rs.pp)+7)/8;
+
+ if (outpos >= pos)
+ return -1; /* We didn't actually compress */
+ *sourcelen = pos;
+ *dstlen = outpos;
+ return 0;
+}
+#if 0
+/* _compress returns the compressed size, -1 if bigger */
+int jffs2_rubinmips_compress(unsigned char *data_in, unsigned char *cpage_out,
+ uint32_t *sourcelen, uint32_t *dstlen, void *model)
+{
+ return rubin_do_compress(BIT_DIVIDER_MIPS, bits_mips, data_in, cpage_out, sourcelen, dstlen);
+}
+#endif
+int jffs2_dynrubin_compress(unsigned char *data_in, unsigned char *cpage_out,
+ uint32_t *sourcelen, uint32_t *dstlen, void *model)
+{
+ int bits[8];
+ unsigned char histo[256];
+ int i;
+ int ret;
+ uint32_t mysrclen, mydstlen;
+
+ mysrclen = *sourcelen;
+ mydstlen = *dstlen - 8;
+
+ if (*dstlen <= 12)
+ return -1;
+
+ memset(histo, 0, 256);
+ for (i=0; i<mysrclen; i++) {
+ histo[data_in[i]]++;
+ }
+ memset(bits, 0, sizeof(int)*8);
+ for (i=0; i<256; i++) {
+ if (i&128)
+ bits[7] += histo[i];
+ if (i&64)
+ bits[6] += histo[i];
+ if (i&32)
+ bits[5] += histo[i];
+ if (i&16)
+ bits[4] += histo[i];
+ if (i&8)
+ bits[3] += histo[i];
+ if (i&4)
+ bits[2] += histo[i];
+ if (i&2)
+ bits[1] += histo[i];
+ if (i&1)
+ bits[0] += histo[i];
+ }
+
+ for (i=0; i<8; i++) {
+ bits[i] = (bits[i] * 256) / mysrclen;
+ if (!bits[i]) bits[i] = 1;
+ if (bits[i] > 255) bits[i] = 255;
+ cpage_out[i] = bits[i];
+ }
+
+ ret = rubin_do_compress(256, bits, data_in, cpage_out+8, &mysrclen, &mydstlen);
+ if (ret)
+ return ret;
+
+ /* Add back the 8 bytes we took for the probabilities */
+ mydstlen += 8;
+
+ if (mysrclen <= mydstlen) {
+ /* We compressed */
+ return -1;
+ }
+
+ *sourcelen = mysrclen;
+ *dstlen = mydstlen;
+ return 0;
+}
+
+static void rubin_do_decompress(int bit_divider, int *bits, unsigned char *cdata_in,
+ unsigned char *page_out, uint32_t srclen, uint32_t destlen)
+{
+ int outpos = 0;
+ struct rubin_state rs;
+
+ init_pushpull(&rs.pp, cdata_in, srclen, 0, 0);
+ init_decode(&rs, bit_divider, bits);
+
+ while (outpos < destlen) {
+ page_out[outpos++] = in_byte(&rs);
+ }
+}
+
+
+int jffs2_rubinmips_decompress(unsigned char *data_in, unsigned char *cpage_out,
+ uint32_t sourcelen, uint32_t dstlen, void *model)
+{
+ rubin_do_decompress(BIT_DIVIDER_MIPS, bits_mips, data_in, cpage_out, sourcelen, dstlen);
+ return 0;
+}
+
+int jffs2_dynrubin_decompress(unsigned char *data_in, unsigned char *cpage_out,
+ uint32_t sourcelen, uint32_t dstlen, void *model)
+{
+ int bits[8];
+ int c;
+
+ for (c=0; c<8; c++)
+ bits[c] = data_in[c];
+
+ rubin_do_decompress(256, bits, data_in+8, cpage_out, sourcelen-8, dstlen);
+ return 0;
+}
+
+static struct jffs2_compressor jffs2_rubinmips_comp = {
+ .priority = JFFS2_RUBINMIPS_PRIORITY,
+ .name = "rubinmips",
+ .compr = JFFS2_COMPR_DYNRUBIN,
+ .compress = NULL, /*&jffs2_rubinmips_compress,*/
+ .decompress = &jffs2_rubinmips_decompress,
+#ifdef JFFS2_RUBINMIPS_DISABLED
+ .disabled = 1,
+#else
+ .disabled = 0,
+#endif
+};
+
+int jffs2_rubinmips_init(void)
+{
+ return jffs2_register_compressor(&jffs2_rubinmips_comp);
+}
+
+void jffs2_rubinmips_exit(void)
+{
+ jffs2_unregister_compressor(&jffs2_rubinmips_comp);
+}
+
+static struct jffs2_compressor jffs2_dynrubin_comp = {
+ .priority = JFFS2_DYNRUBIN_PRIORITY,
+ .name = "dynrubin",
+ .compr = JFFS2_COMPR_RUBINMIPS,
+ .compress = jffs2_dynrubin_compress,
+ .decompress = &jffs2_dynrubin_decompress,
+#ifdef JFFS2_DYNRUBIN_DISABLED
+ .disabled = 1,
+#else
+ .disabled = 0,
+#endif
+};
+
+int jffs2_dynrubin_init(void)
+{
+ return jffs2_register_compressor(&jffs2_dynrubin_comp);
+}
+
+void jffs2_dynrubin_exit(void)
+{
+ jffs2_unregister_compressor(&jffs2_dynrubin_comp);
+}