summaryrefslogtreecommitdiff
path: root/archival/libunarchive
diff options
context:
space:
mode:
authorRob Landley2006-01-20 18:28:50 +0000
committerRob Landley2006-01-20 18:28:50 +0000
commitc1d69906a0c5f28f3d84c14afb3b74c8f19f81c1 (patch)
tree5e3796c33b995720bcd69f2b969e409e85bff119 /archival/libunarchive
parent7a43bd07e64e6db795d4661321da1cab14d9c4f6 (diff)
downloadbusybox-c1d69906a0c5f28f3d84c14afb3b74c8f19f81c1.zip
busybox-c1d69906a0c5f28f3d84c14afb3b74c8f19f81c1.tar.gz
Patch from Aurelien Jacobs to add unlzma. (A new decompression type,
see www.7-zip.org)
Diffstat (limited to 'archival/libunarchive')
-rw-r--r--archival/libunarchive/Makefile.in3
-rw-r--r--archival/libunarchive/decompress_unlzma.c347
-rw-r--r--archival/libunarchive/filter_accept_list_reassign.c4
-rw-r--r--archival/libunarchive/get_header_tar_lzma.c23
-rw-r--r--archival/libunarchive/rangecoder.h158
5 files changed, 535 insertions, 0 deletions
diff --git a/archival/libunarchive/Makefile.in b/archival/libunarchive/Makefile.in
index 99eb638..2b49398 100644
--- a/archival/libunarchive/Makefile.in
+++ b/archival/libunarchive/Makefile.in
@@ -51,17 +51,20 @@ DPKG_FILES:= \
LIBUNARCHIVE-$(CONFIG_AR) += get_header_ar.o unpack_ar_archive.o
LIBUNARCHIVE-$(CONFIG_BUNZIP2) += decompress_bunzip2.o
+LIBUNARCHIVE-$(CONFIG_UNLZMA) += decompress_unlzma.o
LIBUNARCHIVE-$(CONFIG_CPIO) += get_header_cpio.o
LIBUNARCHIVE-$(CONFIG_DPKG) += $(DPKG_FILES)
LIBUNARCHIVE-$(CONFIG_DPKG_DEB) += $(DPKG_FILES)
LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_GZ) += $(GUNZIP_FILES) get_header_tar_gz.o
LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_BZ2) += decompress_bunzip2.o get_header_tar_bz2.o
+LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_LZMA) += decompress_unlzma.o get_header_tar_lzma.o
LIBUNARCHIVE-$(CONFIG_GUNZIP) += $(GUNZIP_FILES)
LIBUNARCHIVE-$(CONFIG_FEATURE_GUNZIP_UNCOMPRESS) += decompress_uncompress.o
LIBUNARCHIVE-$(CONFIG_RPM2CPIO) += $(GUNZIP_FILES) get_header_cpio.o
LIBUNARCHIVE-$(CONFIG_RPM) += $(GUNZIP_FILES) get_header_cpio.o
LIBUNARCHIVE-$(CONFIG_TAR) += get_header_tar.o
LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_BZIP2) += decompress_bunzip2.o get_header_tar_bz2.o
+LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_LZMA) += decompress_unlzma.o get_header_tar_lzma.o
LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_GZIP) += $(GUNZIP_FILES) get_header_tar_gz.o
LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_COMPRESS) += decompress_uncompress.o
LIBUNARCHIVE-$(CONFIG_UNCOMPRESS) += decompress_uncompress.o
diff --git a/archival/libunarchive/decompress_unlzma.c b/archival/libunarchive/decompress_unlzma.c
new file mode 100644
index 0000000..977cb48
--- /dev/null
+++ b/archival/libunarchive/decompress_unlzma.c
@@ -0,0 +1,347 @@
+/*
+ * Small lzma deflate implementation.
+ * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (C) 1999-2005 Igor Pavlov
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <byteswap.h>
+
+#include "libbb.h"
+
+#include "rangecoder.h"
+
+
+typedef struct {
+ uint8_t pos;
+ uint32_t dict_size;
+ uint64_t dst_size;
+} __attribute__ ((packed)) lzma_header_t;
+
+
+#define LZMA_BASE_SIZE 1846
+#define LZMA_LIT_SIZE 768
+
+#define LZMA_NUM_POS_BITS_MAX 4
+
+#define LZMA_LEN_NUM_LOW_BITS 3
+#define LZMA_LEN_NUM_MID_BITS 3
+#define LZMA_LEN_NUM_HIGH_BITS 8
+
+#define LZMA_LEN_CHOICE 0
+#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
+#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
+#define LZMA_LEN_MID (LZMA_LEN_LOW \
+ + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
+#define LZMA_LEN_HIGH (LZMA_LEN_MID \
+ +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
+#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
+
+#define LZMA_NUM_STATES 12
+#define LZMA_NUM_LIT_STATES 7
+
+#define LZMA_START_POS_MODEL_INDEX 4
+#define LZMA_END_POS_MODEL_INDEX 14
+#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
+
+#define LZMA_NUM_POS_SLOT_BITS 6
+#define LZMA_NUM_LEN_TO_POS_STATES 4
+
+#define LZMA_NUM_ALIGN_BITS 4
+
+#define LZMA_MATCH_MIN_LEN 2
+
+#define LZMA_IS_MATCH 0
+#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES <<LZMA_NUM_POS_BITS_MAX))
+#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
+#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
+ + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
+#define LZMA_SPEC_POS (LZMA_POS_SLOT \
+ +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
+#define LZMA_ALIGN (LZMA_SPEC_POS \
+ + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
+#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
+#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
+#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
+
+
+int unlzma(int src_fd, int dst_fd)
+{
+ lzma_header_t header;
+ int lc, pb, lp;
+ uint32_t pos_state_mask;
+ uint32_t literal_pos_mask;
+ uint32_t pos;
+ uint16_t *p;
+ uint16_t *prob;
+ uint16_t *prob_lit;
+ int num_bits;
+ int num_probs;
+ rc_t rc;
+ int i, mi;
+ uint8_t *buffer;
+ uint8_t previous_byte = 0;
+ size_t buffer_pos = 0, global_pos = 0;
+ int len = 0;
+ int state = 0;
+ uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
+
+ if (read(src_fd, &header, sizeof(header)) != sizeof(header))
+ bb_error_msg_and_die("can't read header");
+
+ if (header.pos >= (9 * 5 * 5))
+ bb_error_msg_and_die("bad header");
+ mi = header.pos / 9;
+ lc = header.pos % 9;
+ pb = mi / 5;
+ lp = mi % 5;
+ pos_state_mask = (1 << pb) - 1;
+ literal_pos_mask = (1 << lp) - 1;
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+ header.dict_size = bswap_32(header.dict_size);
+ header.dst_size = bswap_64(header.dst_size);
+#endif /* __BYTE_ORDER */
+
+ if (header.dict_size == 0)
+ header.dict_size = 1;
+
+ buffer = xmalloc(MIN(header.dst_size, header.dict_size));
+
+ num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
+ p = xmalloc(num_probs * sizeof(*p));
+ num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
+ for (i = 0; i < num_probs; i++)
+ p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
+
+ rc_init(&rc, src_fd, 0x10000);
+
+ while (global_pos + buffer_pos < header.dst_size) {
+ int pos_state = (buffer_pos + global_pos) & pos_state_mask;
+
+ prob =
+ p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
+ if (rc_is_bit_0(&rc, prob)) {
+ mi = 1;
+ rc_update_bit_0(&rc, prob);
+ prob = (p + LZMA_LITERAL + (LZMA_LIT_SIZE
+ * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
+ + (previous_byte >> (8 - lc)))));
+
+ if (state >= LZMA_NUM_LIT_STATES) {
+ int match_byte;
+
+ pos = buffer_pos - rep0;
+ while (pos >= header.dict_size)
+ pos += header.dict_size;
+ match_byte = buffer[pos];
+ do {
+ int bit;
+
+ match_byte <<= 1;
+ bit = match_byte & 0x100;
+ prob_lit = prob + 0x100 + bit + mi;
+ if (rc_get_bit(&rc, prob_lit, &mi)) {
+ if (!bit)
+ break;
+ } else {
+ if (bit)
+ break;
+ }
+ } while (mi < 0x100);
+ }
+ while (mi < 0x100) {
+ prob_lit = prob + mi;
+ rc_get_bit(&rc, prob_lit, &mi);
+ }
+ previous_byte = (uint8_t) mi;
+
+ buffer[buffer_pos++] = previous_byte;
+ if (buffer_pos == header.dict_size) {
+ buffer_pos = 0;
+ global_pos += header.dict_size;
+ write(dst_fd, buffer, header.dict_size);
+ }
+ if (state < 4)
+ state = 0;
+ else if (state < 10)
+ state -= 3;
+ else
+ state -= 6;
+ } else {
+ int offset;
+ uint16_t *prob_len;
+
+ rc_update_bit_1(&rc, prob);
+ prob = p + LZMA_IS_REP + state;
+ if (rc_is_bit_0(&rc, prob)) {
+ rc_update_bit_0(&rc, prob);
+ rep3 = rep2;
+ rep2 = rep1;
+ rep1 = rep0;
+ state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
+ prob = p + LZMA_LEN_CODER;
+ } else {
+ rc_update_bit_1(&rc, prob);
+ prob = p + LZMA_IS_REP_G0 + state;
+ if (rc_is_bit_0(&rc, prob)) {
+ rc_update_bit_0(&rc, prob);
+ prob = (p + LZMA_IS_REP_0_LONG
+ + (state << LZMA_NUM_POS_BITS_MAX) + pos_state);
+ if (rc_is_bit_0(&rc, prob)) {
+ rc_update_bit_0(&rc, prob);
+
+ state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
+ pos = buffer_pos - rep0;
+ while (pos >= header.dict_size)
+ pos += header.dict_size;
+ previous_byte = buffer[pos];
+ buffer[buffer_pos++] = previous_byte;
+ if (buffer_pos == header.dict_size) {
+ buffer_pos = 0;
+ global_pos += header.dict_size;
+ write(dst_fd, buffer, header.dict_size);
+ }
+ continue;
+ } else {
+ rc_update_bit_1(&rc, prob);
+ }
+ } else {
+ uint32_t distance;
+
+ rc_update_bit_1(&rc, prob);
+ prob = p + LZMA_IS_REP_G1 + state;
+ if (rc_is_bit_0(&rc, prob)) {
+ rc_update_bit_0(&rc, prob);
+ distance = rep1;
+ } else {
+ rc_update_bit_1(&rc, prob);
+ prob = p + LZMA_IS_REP_G2 + state;
+ if (rc_is_bit_0(&rc, prob)) {
+ rc_update_bit_0(&rc, prob);
+ distance = rep2;
+ } else {
+ rc_update_bit_1(&rc, prob);
+ distance = rep3;
+ rep3 = rep2;
+ }
+ rep2 = rep1;
+ }
+ rep1 = rep0;
+ rep0 = distance;
+ }
+ state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
+ prob = p + LZMA_REP_LEN_CODER;
+ }
+
+ prob_len = prob + LZMA_LEN_CHOICE;
+ if (rc_is_bit_0(&rc, prob_len)) {
+ rc_update_bit_0(&rc, prob_len);
+ prob_len = (prob + LZMA_LEN_LOW
+ + (pos_state << LZMA_LEN_NUM_LOW_BITS));
+ offset = 0;
+ num_bits = LZMA_LEN_NUM_LOW_BITS;
+ } else {
+ rc_update_bit_1(&rc, prob_len);
+ prob_len = prob + LZMA_LEN_CHOICE_2;
+ if (rc_is_bit_0(&rc, prob_len)) {
+ rc_update_bit_0(&rc, prob_len);
+ prob_len = (prob + LZMA_LEN_MID
+ + (pos_state << LZMA_LEN_NUM_MID_BITS));
+ offset = 1 << LZMA_LEN_NUM_LOW_BITS;
+ num_bits = LZMA_LEN_NUM_MID_BITS;
+ } else {
+ rc_update_bit_1(&rc, prob_len);
+ prob_len = prob + LZMA_LEN_HIGH;
+ offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
+ + (1 << LZMA_LEN_NUM_MID_BITS));
+ num_bits = LZMA_LEN_NUM_HIGH_BITS;
+ }
+ }
+ rc_bit_tree_decode(&rc, prob_len, num_bits, &len);
+ len += offset;
+
+ if (state < 4) {
+ int pos_slot;
+
+ state += LZMA_NUM_LIT_STATES;
+ prob =
+ p + LZMA_POS_SLOT +
+ ((len <
+ LZMA_NUM_LEN_TO_POS_STATES ? len :
+ LZMA_NUM_LEN_TO_POS_STATES - 1)
+ << LZMA_NUM_POS_SLOT_BITS);
+ rc_bit_tree_decode(&rc, prob, LZMA_NUM_POS_SLOT_BITS,
+ &pos_slot);
+ if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
+ num_bits = (pos_slot >> 1) - 1;
+ rep0 = 2 | (pos_slot & 1);
+ if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
+ rep0 <<= num_bits;
+ prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
+ } else {
+ num_bits -= LZMA_NUM_ALIGN_BITS;
+ while (num_bits--)
+ rep0 = (rep0 << 1) | rc_direct_bit(&rc);
+ prob = p + LZMA_ALIGN;
+ rep0 <<= LZMA_NUM_ALIGN_BITS;
+ num_bits = LZMA_NUM_ALIGN_BITS;
+ }
+ i = 1;
+ mi = 1;
+ while (num_bits--) {
+ if (rc_get_bit(&rc, prob + mi, &mi))
+ rep0 |= i;
+ i <<= 1;
+ }
+ } else
+ rep0 = pos_slot;
+ if (++rep0 == 0)
+ break;
+ }
+
+ len += LZMA_MATCH_MIN_LEN;
+
+ do {
+ pos = buffer_pos - rep0;
+ while (pos >= header.dict_size)
+ pos += header.dict_size;
+ previous_byte = buffer[pos];
+ buffer[buffer_pos++] = previous_byte;
+ if (buffer_pos == header.dict_size) {
+ buffer_pos = 0;
+ global_pos += header.dict_size;
+ write(dst_fd, buffer, header.dict_size);
+ }
+ len--;
+ } while (len != 0 && buffer_pos < header.dst_size);
+ }
+ }
+
+ write(dst_fd, buffer, buffer_pos);
+ rc_free(&rc);
+ return 0;
+}
+
+/* vi:set ts=4: */
diff --git a/archival/libunarchive/filter_accept_list_reassign.c b/archival/libunarchive/filter_accept_list_reassign.c
index d043654..a09f564 100644
--- a/archival/libunarchive/filter_accept_list_reassign.c
+++ b/archival/libunarchive/filter_accept_list_reassign.c
@@ -50,6 +50,10 @@ extern char filter_accept_list_reassign(archive_handle_t *archive_handle)
return(EXIT_SUCCESS);
}
#endif
+ if (ENABLE_FEATURE_DEB_TAR_LZMA && !strcmp(name_ptr, ".lzma")) {
+ archive_handle->action_data_subarchive = get_header_tar_lzma;
+ return(EXIT_SUCCESS);
+ }
}
return(EXIT_FAILURE);
}
diff --git a/archival/libunarchive/get_header_tar_lzma.c b/archival/libunarchive/get_header_tar_lzma.c
new file mode 100644
index 0000000..63dc8bc
--- /dev/null
+++ b/archival/libunarchive/get_header_tar_lzma.c
@@ -0,0 +1,23 @@
+/*
+ * Small lzma deflate implementation.
+ * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
+ *
+ * Licensed under GPL v2, see file LICENSE in this tarball for details.
+ */
+
+#include "unarchive.h"
+
+char get_header_tar_lzma(archive_handle_t * archive_handle)
+{
+ /* Can't lseek over pipes */
+ archive_handle->seek = seek_by_char;
+
+ archive_handle->src_fd = open_transformer(archive_handle->src_fd, unlzma);
+ archive_handle->offset = 0;
+ while (get_header_tar(archive_handle) == EXIT_SUCCESS);
+
+ /* Can only do one file at a time */
+ return EXIT_FAILURE;
+}
+
+/* vi:set ts=4: */
diff --git a/archival/libunarchive/rangecoder.h b/archival/libunarchive/rangecoder.h
new file mode 100644
index 0000000..bb41591
--- /dev/null
+++ b/archival/libunarchive/rangecoder.h
@@ -0,0 +1,158 @@
+/*
+ * Small range coder implementation for lzma.
+ * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (c) 1999-2005 Igor Pavlov
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+
+#include "libbb.h"
+
+#ifndef always_inline
+# if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >0)
+# define always_inline __attribute__((always_inline)) inline
+# else
+# define always_inline inline
+# endif
+#endif
+
+#ifdef CONFIG_FEATURE_LZMA_FAST
+# define speed_inline always_inline
+#else
+# define speed_inline
+#endif
+
+
+typedef struct {
+ int fd;
+ uint8_t *ptr;
+ uint8_t *buffer;
+ uint8_t *buffer_end;
+ int buffer_size;
+ uint32_t code;
+ uint32_t range;
+ uint32_t bound;
+} rc_t;
+
+
+#define RC_TOP_BITS 24
+#define RC_MOVE_BITS 5
+#define RC_MODEL_TOTAL_BITS 11
+
+
+static speed_inline void rc_read(rc_t * rc)
+{
+ rc->buffer_size = read(rc->fd, rc->buffer, rc->buffer_size);
+ if (rc->buffer_size <= 0)
+ bb_error_msg_and_die("unexpected EOF");
+ rc->ptr = rc->buffer;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+}
+
+static always_inline void rc_init(rc_t * rc, int fd, int buffer_size)
+{
+ int i;
+
+ rc->fd = fd;
+ rc->buffer = malloc(buffer_size);
+ rc->buffer_size = buffer_size;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+ rc->ptr = rc->buffer_end;
+
+ rc->code = 0;
+ rc->range = 0xFFFFFFFF;
+ for (i = 0; i < 5; i++) {
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->code = (rc->code << 8) | *rc->ptr++;
+ }
+}
+
+static always_inline void rc_free(rc_t * rc)
+{
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(rc->buffer);
+}
+
+static always_inline void rc_normalize(rc_t * rc)
+{
+ if (rc->range < (1 << RC_TOP_BITS)) {
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->range <<= 8;
+ rc->code = (rc->code << 8) | *rc->ptr++;
+ }
+}
+
+static speed_inline int rc_is_bit_0(rc_t * rc, uint16_t * p)
+{
+ rc_normalize(rc);
+ rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
+ return rc->code < rc->bound;
+}
+
+static speed_inline void rc_update_bit_0(rc_t * rc, uint16_t * p)
+{
+ rc->range = rc->bound;
+ *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
+}
+
+static speed_inline void rc_update_bit_1(rc_t * rc, uint16_t * p)
+{
+ rc->range -= rc->bound;
+ rc->code -= rc->bound;
+ *p -= *p >> RC_MOVE_BITS;
+}
+
+static speed_inline int rc_get_bit(rc_t * rc, uint16_t * p, int *symbol)
+{
+ if (rc_is_bit_0(rc, p)) {
+ rc_update_bit_0(rc, p);
+ *symbol *= 2;
+ return 0;
+ } else {
+ rc_update_bit_1(rc, p);
+ *symbol = *symbol * 2 + 1;
+ return 1;
+ }
+}
+
+static always_inline int rc_direct_bit(rc_t * rc)
+{
+ rc_normalize(rc);
+ rc->range >>= 1;
+ if (rc->code >= rc->range) {
+ rc->code -= rc->range;
+ return 1;
+ }
+ return 0;
+}
+
+static speed_inline void
+rc_bit_tree_decode(rc_t * rc, uint16_t * p, int num_levels, int *symbol)
+{
+ int i = num_levels;
+
+ *symbol = 1;
+ while (i--)
+ rc_get_bit(rc, p + *symbol, symbol);
+ *symbol -= 1 << num_levels;
+}
+
+/* vi:set ts=4: */