kevin/linux
1
Fork 0
Code
adc218676e
linux/lib/decompress_unlzma.c
Linus Torvalds 1a251f52cf minmax: make generic MIN() and MAX() macros available everywhere 
This just standardizes the use of MIN() and MAX() macros, with the very
traditional semantics.  The goal is to use these for C constant
expressions and for top-level / static initializers, and so be able to
simplify the min()/max() macros.

These macro names were used by various kernel code - they are very
traditional, after all - and all such users have been fixed up, with a
few different approaches:

 - trivial duplicated macro definitions have been removed

   Note that 'trivial' here means that it's obviously kernel code that
   already included all the major kernel headers, and thus gets the new
   generic MIN/MAX macros automatically.

 - non-trivial duplicated macro definitions are guarded with #ifndef

   This is the "yes, they define their own versions, but no, the include
   situation is not entirely obvious, and maybe they don't get the
   generic version automatically" case.

 - strange use case #1

   A couple of drivers decided that the way they want to describe their
   versioning is with

	#define MAJ 1
	#define MIN 2
	#define DRV_VERSION __stringify(MAJ) "." __stringify(MIN)

   which adds zero value and I just did my Alexander the Great
   impersonation, and rewrote that pointless Gordian knot as

	#define DRV_VERSION "1.2"

   instead.

 - strange use case #2

   A couple of drivers thought that it's a good idea to have a random
   'MIN' or 'MAX' define for a value or index into a table, rather than
   the traditional macro that takes arguments.

   These values were re-written as C enum's instead. The new
   function-line macros only expand when followed by an open
   parenthesis, and thus don't clash with enum use.

Happily, there weren't really all that many of these cases, and a lot of
users already had the pattern of using '#ifndef' guarding (or in one
case just using '#undef MIN') before defining their own private version
that does the same thing. I left such cases alone.

Cc: David Laight <David.Laight@aculab.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-07-28 15:49:18 -07:00

682 lines
16 KiB
C
Raw Blame History

/* 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 (https://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
*/
#ifdef STATIC
#define PREBOOT
#else
#include <linux/decompress/unlzma.h>
#endif /* STATIC */
#include <linux/decompress/mm.h>
#ifndef MIN
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#endif
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 (https://www.7-zip.org/)
*Copyright (c) 1999-2005 Igor Pavlov
*/
#include <linux/compiler.h>
#define LZMA_IOBUF_SIZE 0x10000
struct rc {
long (*fill)(void*, unsigned long);
uint8_t *ptr;
uint8_t *buffer;
uint8_t *buffer_end;
long buffer_size;
uint32_t code;
uint32_t range;
uint32_t bound;
void (*error)(char *);
};
#define RC_TOP_BITS 24
#define RC_MOVE_BITS 5
#define RC_MODEL_TOTAL_BITS 11
static long INIT nofill(void *buffer, unsigned long len)
{
return -1;
}
/* 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)
rc->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,
long (*fill)(void*, unsigned long),
char *buffer, long buffer_size)
{
if (fill)
rc->fill = fill;
else
rc->fill = nofill;
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 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 INIT 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 (https://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;
long (*flush)(void*, unsigned long);
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 int 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;
if (wr->flush((char *)wr->buffer, wr->header->dict_size)
!= wr->header->dict_size)
return -1;
}
return 0;
}
static inline int INIT copy_byte(struct writer *wr, uint32_t offs)
{
return write_byte(wr, peek_old_byte(wr, offs));
}
static inline int INIT copy_bytes(struct writer *wr,
uint32_t rep0, int len)
{
do {
if (copy_byte(wr, rep0))
return -1;
len--;
} while (len != 0 && wr->buffer_pos < wr->header->dst_size);
return len;
}
static inline int 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);
}
if (cst->state < 4)
cst->state = 0;
else if (cst->state < 10)
cst->state -= 3;
else
cst->state -= 6;
return write_byte(wr, mi);
}
static inline int 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;
return copy_byte(wr, cst->rep0);
} 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 0;
if (cst->rep0 > wr->header->dict_size
|| cst->rep0 > get_pos(wr))
return -1;
}
len += LZMA_MATCH_MIN_LEN;
return copy_bytes(wr, cst->rep0, len);
}
STATIC inline int INIT unlzma(unsigned char *buf, long in_len,
long (*fill)(void*, unsigned long),
long (*flush)(void*, unsigned long),
unsigned char *output,
long *posp,
void(*error)(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;
rc.error = error;
if (buf)
inbuf = buf;
else
inbuf = malloc(LZMA_IOBUF_SIZE);
if (!inbuf) {
error("Could not allocate input buffer");
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");
goto exit_1;
}
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 == NULL)
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)) {
if (process_bit0(&wr, &rc, &cst, p, pos_state, prob,
lc, literal_pos_mask)) {
error("LZMA data is corrupt");
goto exit_3;
}
} else {
if (process_bit1(&wr, &rc, &cst, p, pos_state, prob)) {
error("LZMA data is corrupt");
goto exit_3;
}
if (cst.rep0 == 0)
break;
}
if (rc.buffer_size <= 0)
goto exit_3;
}
if (posp)
*posp = rc.ptr-rc.buffer;
if (!wr.flush || wr.flush(wr.buffer, wr.buffer_pos) == wr.buffer_pos)
ret = 0;
exit_3:
large_free(p);
exit_2:
if (!output)
large_free(wr.buffer);
exit_1:
if (!buf)
free(inbuf);
exit_0:
return ret;
}
#ifdef PREBOOT
STATIC int INIT __decompress(unsigned char *buf, long in_len,
long (*fill)(void*, unsigned long),
long (*flush)(void*, unsigned long),
unsigned char *output, long out_len,
long *posp,
void (*error)(char *x))
{
return unlzma(buf, in_len - 4, fill, flush, output, posp, error);
}
#endif
View Git Blame Copy Permalink