]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - lib/decompress_unlzma.c
Merge branch 'linus' into locking-for-linus
[linux-2.6-omap-h63xx.git] / lib / decompress_unlzma.c
diff --git a/lib/decompress_unlzma.c b/lib/decompress_unlzma.c
new file mode 100644 (file)
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--- /dev/null
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+/* 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>
+
+#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