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-rw-r--r--lib/decompress_unlzma.c648
1 files changed, 648 insertions, 0 deletions
diff --git a/lib/decompress_unlzma.c b/lib/decompress_unlzma.c
new file mode 100644
index 000000000000..32123a1340e6
--- /dev/null
+++ b/lib/decompress_unlzma.c
@@ -0,0 +1,648 @@
+/* Lzma decompressor for Linux kernel. Shamelessly snarfed
+ *from busybox 1.1.1
+ *
+ *Linux kernel adaptation
+ *Copyright (C) 2006 Alain < alain@knaff.lu >
+ *
+ *Based on small lzma deflate implementation/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
+ *
+ *Copyrights of the parts, see headers below.
+ *
+ *
+ *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
+ */
+
+#ifndef STATIC
+#include <linux/decompress/unlzma.h>
+#endif /* STATIC */
+
+#include <linux/decompress/mm.h>
+#include <linux/slab.h>
+
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+static long long INIT read_int(unsigned char *ptr, int size)
+{
+ int i;
+ long long ret = 0;
+
+ for (i = 0; i < size; i++)
+ ret = (ret << 8) | ptr[size-i-1];
+ return ret;
+}
+
+#define ENDIAN_CONVERT(x) \
+ x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
+
+
+/* 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
+ */
+
+#include <linux/compiler.h>
+
+#define LZMA_IOBUF_SIZE 0x10000
+
+struct rc {
+ int (*fill)(void*, unsigned int);
+ uint8_t *ptr;
+ uint8_t *buffer;
+ uint8_t *buffer_end;
+ int buffer_size;
+ uint32_t code;
+ uint32_t range;
+ uint32_t bound;
+};
+
+
+#define RC_TOP_BITS 24
+#define RC_MOVE_BITS 5
+#define RC_MODEL_TOTAL_BITS 11
+
+
+/* Called twice: once at startup and once in rc_normalize() */
+static void INIT rc_read(struct rc *rc)
+{
+ rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
+ if (rc->buffer_size <= 0)
+ error("unexpected EOF");
+ rc->ptr = rc->buffer;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+}
+
+/* Called once */
+static inline void INIT rc_init(struct rc *rc,
+ int (*fill)(void*, unsigned int),
+ char *buffer, int buffer_size)
+{
+ rc->fill = fill;
+ rc->buffer = (uint8_t *)buffer;
+ rc->buffer_size = buffer_size;
+ rc->buffer_end = rc->buffer + rc->buffer_size;
+ rc->ptr = rc->buffer;
+
+ rc->code = 0;
+ rc->range = 0xFFFFFFFF;
+}
+
+static inline void INIT rc_init_code(struct rc *rc)
+{
+ int i;
+
+ for (i = 0; i < 5; i++) {
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->code = (rc->code << 8) | *rc->ptr++;
+ }
+}
+
+
+/* Called once. TODO: bb_maybe_free() */
+static inline void INIT rc_free(struct rc *rc)
+{
+ free(rc->buffer);
+}
+
+/* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
+static void INIT rc_do_normalize(struct rc *rc)
+{
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->range <<= 8;
+ rc->code = (rc->code << 8) | *rc->ptr++;
+}
+static inline void INIT rc_normalize(struct rc *rc)
+{
+ if (rc->range < (1 << RC_TOP_BITS))
+ rc_do_normalize(rc);
+}
+
+/* Called 9 times */
+/* Why rc_is_bit_0_helper exists?
+ *Because we want to always expose (rc->code < rc->bound) to optimizer
+ */
+static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
+{
+ rc_normalize(rc);
+ rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
+ return rc->bound;
+}
+static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
+{
+ uint32_t t = rc_is_bit_0_helper(rc, p);
+ return rc->code < t;
+}
+
+/* Called ~10 times, but very small, thus inlined */
+static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
+{
+ rc->range = rc->bound;
+ *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
+}
+static inline void rc_update_bit_1(struct rc *rc, uint16_t *p)
+{
+ rc->range -= rc->bound;
+ rc->code -= rc->bound;
+ *p -= *p >> RC_MOVE_BITS;
+}
+
+/* Called 4 times in unlzma loop */
+static int INIT rc_get_bit(struct rc *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;
+ }
+}
+
+/* Called once */
+static inline int INIT rc_direct_bit(struct rc *rc)
+{
+ rc_normalize(rc);
+ rc->range >>= 1;
+ if (rc->code >= rc->range) {
+ rc->code -= rc->range;
+ return 1;
+ }
+ return 0;
+}
+
+/* Called twice */
+static inline void INIT
+rc_bit_tree_decode(struct rc *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;
+}
+
+
+/*
+ * 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
+ */
+
+
+struct lzma_header {
+ uint8_t pos;
+ uint32_t dict_size;
+ uint64_t dst_size;
+} __attribute__ ((packed)) ;
+
+
+#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)
+
+
+struct writer {
+ uint8_t *buffer;
+ uint8_t previous_byte;
+ size_t buffer_pos;
+ int bufsize;
+ size_t global_pos;
+ int(*flush)(void*, unsigned int);
+ struct lzma_header *header;
+};
+
+struct cstate {
+ int state;
+ uint32_t rep0, rep1, rep2, rep3;
+};
+
+static inline size_t INIT get_pos(struct writer *wr)
+{
+ return
+ wr->global_pos + wr->buffer_pos;
+}
+
+static inline uint8_t INIT peek_old_byte(struct writer *wr,
+ uint32_t offs)
+{
+ if (!wr->flush) {
+ int32_t pos;
+ while (offs > wr->header->dict_size)
+ offs -= wr->header->dict_size;
+ pos = wr->buffer_pos - offs;
+ return wr->buffer[pos];
+ } else {
+ uint32_t pos = wr->buffer_pos - offs;
+ while (pos >= wr->header->dict_size)
+ pos += wr->header->dict_size;
+ return wr->buffer[pos];
+ }
+
+}
+
+static inline void INIT write_byte(struct writer *wr, uint8_t byte)
+{
+ wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
+ if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
+ wr->buffer_pos = 0;
+ wr->global_pos += wr->header->dict_size;
+ wr->flush((char *)wr->buffer, wr->header->dict_size);
+ }
+}
+
+
+static inline void INIT copy_byte(struct writer *wr, uint32_t offs)
+{
+ write_byte(wr, peek_old_byte(wr, offs));
+}
+
+static inline void INIT copy_bytes(struct writer *wr,
+ uint32_t rep0, int len)
+{
+ do {
+ copy_byte(wr, rep0);
+ len--;
+ } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
+}
+
+static inline void INIT process_bit0(struct writer *wr, struct rc *rc,
+ struct cstate *cst, uint16_t *p,
+ int pos_state, uint16_t *prob,
+ int lc, uint32_t literal_pos_mask) {
+ int mi = 1;
+ rc_update_bit_0(rc, prob);
+ prob = (p + LZMA_LITERAL +
+ (LZMA_LIT_SIZE
+ * (((get_pos(wr) & literal_pos_mask) << lc)
+ + (wr->previous_byte >> (8 - lc))))
+ );
+
+ if (cst->state >= LZMA_NUM_LIT_STATES) {
+ int match_byte = peek_old_byte(wr, cst->rep0);
+ do {
+ int bit;
+ uint16_t *prob_lit;
+
+ 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) {
+ uint16_t *prob_lit = prob + mi;
+ rc_get_bit(rc, prob_lit, &mi);
+ }
+ write_byte(wr, mi);
+ if (cst->state < 4)
+ cst->state = 0;
+ else if (cst->state < 10)
+ cst->state -= 3;
+ else
+ cst->state -= 6;
+}
+
+static inline void INIT process_bit1(struct writer *wr, struct rc *rc,
+ struct cstate *cst, uint16_t *p,
+ int pos_state, uint16_t *prob) {
+ int offset;
+ uint16_t *prob_len;
+ int num_bits;
+ int len;
+
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ cst->rep3 = cst->rep2;
+ cst->rep2 = cst->rep1;
+ cst->rep1 = cst->rep0;
+ cst->state = cst->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 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ prob = (p + LZMA_IS_REP_0_LONG
+ + (cst->state <<
+ LZMA_NUM_POS_BITS_MAX) +
+ pos_state);
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+
+ cst->state = cst->state < LZMA_NUM_LIT_STATES ?
+ 9 : 11;
+ copy_byte(wr, cst->rep0);
+ return;
+ } else {
+ rc_update_bit_1(rc, prob);
+ }
+ } else {
+ uint32_t distance;
+
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP_G1 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ distance = cst->rep1;
+ } else {
+ rc_update_bit_1(rc, prob);
+ prob = p + LZMA_IS_REP_G2 + cst->state;
+ if (rc_is_bit_0(rc, prob)) {
+ rc_update_bit_0(rc, prob);
+ distance = cst->rep2;
+ } else {
+ rc_update_bit_1(rc, prob);
+ distance = cst->rep3;
+ cst->rep3 = cst->rep2;
+ }
+ cst->rep2 = cst->rep1;
+ }
+ cst->rep1 = cst->rep0;
+ cst->rep0 = distance;
+ }
+ cst->state = cst->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 (cst->state < 4) {
+ int pos_slot;
+
+ cst->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) {
+ int i, mi;
+ num_bits = (pos_slot >> 1) - 1;
+ cst->rep0 = 2 | (pos_slot & 1);
+ if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
+ cst->rep0 <<= num_bits;
+ prob = p + LZMA_SPEC_POS +
+ cst->rep0 - pos_slot - 1;
+ } else {
+ num_bits -= LZMA_NUM_ALIGN_BITS;
+ while (num_bits--)
+ cst->rep0 = (cst->rep0 << 1) |
+ rc_direct_bit(rc);
+ prob = p + LZMA_ALIGN;
+ cst->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))
+ cst->rep0 |= i;
+ i <<= 1;
+ }
+ } else
+ cst->rep0 = pos_slot;
+ if (++(cst->rep0) == 0)
+ return;
+ }
+
+ len += LZMA_MATCH_MIN_LEN;
+
+ copy_bytes(wr, cst->rep0, len);
+}
+
+
+
+STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
+ int(*fill)(void*, unsigned int),
+ int(*flush)(void*, unsigned int),
+ unsigned char *output,
+ int *posp,
+ void(*error_fn)(char *x)
+ )
+{
+ struct lzma_header header;
+ int lc, pb, lp;
+ uint32_t pos_state_mask;
+ uint32_t literal_pos_mask;
+ uint16_t *p;
+ int num_probs;
+ struct rc rc;
+ int i, mi;
+ struct writer wr;
+ struct cstate cst;
+ unsigned char *inbuf;
+ int ret = -1;
+
+ set_error_fn(error_fn);
+ if (!flush)
+ in_len -= 4; /* Uncompressed size hack active in pre-boot
+ environment */
+ if (buf)
+ inbuf = buf;
+ else
+ inbuf = malloc(LZMA_IOBUF_SIZE);
+ if (!inbuf) {
+ error("Could not allocate input bufer");
+ goto exit_0;
+ }
+
+ cst.state = 0;
+ cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
+
+ wr.header = &header;
+ wr.flush = flush;
+ wr.global_pos = 0;
+ wr.previous_byte = 0;
+ wr.buffer_pos = 0;
+
+ rc_init(&rc, fill, inbuf, in_len);
+
+ for (i = 0; i < sizeof(header); i++) {
+ if (rc.ptr >= rc.buffer_end)
+ rc_read(&rc);
+ ((unsigned char *)&header)[i] = *rc.ptr++;
+ }
+
+ if (header.pos >= (9 * 5 * 5))
+ error("bad header");
+
+ mi = 0;
+ lc = header.pos;
+ while (lc >= 9) {
+ mi++;
+ lc -= 9;
+ }
+ pb = 0;
+ lp = mi;
+ while (lp >= 5) {
+ pb++;
+ lp -= 5;
+ }
+ pos_state_mask = (1 << pb) - 1;
+ literal_pos_mask = (1 << lp) - 1;
+
+ ENDIAN_CONVERT(header.dict_size);
+ ENDIAN_CONVERT(header.dst_size);
+
+ if (header.dict_size == 0)
+ header.dict_size = 1;
+
+ if (output)
+ wr.buffer = output;
+ else {
+ wr.bufsize = MIN(header.dst_size, header.dict_size);
+ wr.buffer = large_malloc(wr.bufsize);
+ }
+ if (wr.buffer == NULL)
+ goto exit_1;
+
+ num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
+ p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
+ if (p == 0)
+ goto exit_2;
+ 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_code(&rc);
+
+ while (get_pos(&wr) < header.dst_size) {
+ int pos_state = get_pos(&wr) & pos_state_mask;
+ uint16_t *prob = p + LZMA_IS_MATCH +
+ (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
+ if (rc_is_bit_0(&rc, prob))
+ process_bit0(&wr, &rc, &cst, p, pos_state, prob,
+ lc, literal_pos_mask);
+ else {
+ process_bit1(&wr, &rc, &cst, p, pos_state, prob);
+ if (cst.rep0 == 0)
+ break;
+ }
+ }
+
+ if (posp)
+ *posp = rc.ptr-rc.buffer;
+ if (wr.flush)
+ wr.flush(wr.buffer, wr.buffer_pos);
+ ret = 0;
+ large_free(p);
+exit_2:
+ if (!output)
+ large_free(wr.buffer);
+exit_1:
+ if (!buf)
+ free(inbuf);
+exit_0:
+ return ret;
+}
+
+#define decompress unlzma
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-15 00:02:19 +0000