windows-nt/Source/XPSP1/NT/base/ntos/rtl/xencode.c
2020-09-26 16:20:57 +08:00

1294 lines
28 KiB
C

/* -------------------------------------------------------------------- */
/* */
/* Copyright (c) 1991-1999 by Andrew Kadatch */
/* */
/* -------------------------------------------------------------------- */
#include "xprs.h"
#define MAX_CHAIN 9
// Zobrist hashing
#define Z_HASH_SIZE_LOG (BUFF_SIZE_LOG - 1)
#define Z_HASH_SIZE (1 << Z_HASH_SIZE_LOG)
#define Z_HASH_SUM(b) (z_hash_map[0][b[0]] ^ z_hash_map[1][b[1]] ^ z_hash_map[2][b[2]])
// quick hashing
#define Q_HASH_SH1 3
#define Q_HASH_SH2 (Q_HASH_SH1 >> 1)
#define Q_HASH_SUM3(c1,c2,c3) (((c1) << Q_HASH_SH1) + ((c2) << Q_HASH_SH2) + (c3))
#define Q_HASH_SUM(b) Q_HASH_SUM3 (b[0], b[1], b[2])
#define Q_HASH_SIZE (Q_HASH_SUM3 (255, 255, 255) + 1)
#define z_hash_t uint16
#define z_index_t uint16
#if CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
typedef struct huff_node_t huff_node;
struct huff_node_t
{
huff_node *son[2];
uxint freq;
uint16 ch;
uint16 bits;
};
typedef struct
{
huff_node buff[2 * HUFF_SIZE], *head[256], **link[256];
} huff_info;
#endif
typedef struct
{
struct
{
#if CODING == CODING_BY_BIT
xint bits;
uchar *ptr;
#elif CODING & (CODING_DIRECT | CODING_DIRECT2)
uchar *ptr;
#elif CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
uxint freq[HUFF_SIZE];
uxint mask[HUFF_SIZE];
uchar bits[HUFF_SIZE];
huff_info info;
uxint pointers;
uxint extra;
uxint masks;
#endif /* CODING */
} stat;
xint chain;
xint max_size;
struct
{
uchar *beg;
uchar *ptr;
} comp;
struct
{
z_index_t *hash;
uchar *beg;
uchar *ptr;
uchar *tag_ptr;
tag_t tag_mask;
} temp;
struct
{
xint len;
xint pos;
} match;
struct
{
xint pos;
xint size;
xint stop;
xint progress;
const uchar *ptr;
const uchar *end;
const uchar *end_16;
const uchar *end_3;
const uchar *ptr_stop;
} orig;
} context;
#define v p[-1].c
typedef struct
{
union
{
z_index_t z_next[16];
const uchar *q_last[16];
} x;
context c;
} prs;
#define MAGIC_ENCODE 0x53E7C0DE
typedef struct
{
int magic;
void *memory;
prs *p;
uchar *temp;
unsigned max_size;
int chain;
} xpress_info;
#if MAX_CHAIN >= 1
static z_hash_t z_hash_map[MIN_MATCH][256];
static int z_hash_map_initialized = 0;
static void z_hash_map_init (void)
{
long v1, v2;
z_hash_t *m;
if (z_hash_map_initialized)
return;
v1 = 0x13579bdfL; v2 = 0x87654321L;
for (m = z_hash_map[0]; m < z_hash_map[0] + sizeof (z_hash_map) / sizeof (z_hash_map[0][0]); ++m)
{
long vv1 = v2, vv2 = v1, d = 0;
xint i = 32;
do
{
d += 0x9e3779b9L; vv1 += d; vv2 += d;
v1 += ((v2<<3) + vv1) ^ (v2 + d) ^ ((v2>>5) + vv2);
v2 += ((v1<<3) + vv2) ^ (v1 + d) ^ ((v1>>5) + vv1);
--i;
}
while (i);
*m = (z_hash_t) ((v1 += v2) & (Z_HASH_SIZE - 1));
}
z_hash_map_initialized = 1;
}
static void z_hash_insert (prs *p)
{
const uchar *b, *e;
xint n, h;
z_index_t *hash = v.temp.hash;
e = v.orig.end - (MIN_MATCH-1);
b = v.orig.ptr;
n = 0;
for (; b < e; ++b, ++n)
{
h = Z_HASH_SUM (b);
p->x.z_next[n] = hash[h];
hash[h] = (z_index_t) n;
}
e += MIN_MATCH-1;
for (; b < e; ++b, ++n)
p->x.z_next[n] = 0;
}
#endif
#if CODING != CODING_BY_BIT
static void tag_write_start (prs *p)
{
v.temp.tag_ptr = v.temp.ptr;
v.temp.ptr += sizeof (v.temp.tag_mask);
v.temp.tag_mask = 1;
}
#if CODING == CODING_HUFF_ALL
#define INC_MASKS ++v.stat.masks
#else
#define INC_MASKS
#endif
#define tag_write(p,ptr,n) \
{ \
tag_t __n = n | (v.temp.tag_mask << 1); \
if (v.temp.tag_mask < 0) \
{ \
*(__unaligned tag_t *) v.temp.tag_ptr = __n; \
v.temp.tag_ptr = ptr; \
ptr += sizeof (v.temp.tag_mask); \
INC_MASKS; \
__n = 1; \
} \
v.temp.tag_mask = __n; \
}
static void tag_write_finish (prs *p)
{
uchar *ptr = v.temp.ptr;
do
{
tag_write (p, ptr, 1);
}
while (ptr == v.temp.ptr);
}
#elif CODING == CODING_BY_BIT
static void tag_write_start (prs *p)
{
v.temp.tag_ptr = (uchar *) &v.temp.tag_mask;
v.temp.tag_mask = 0;
v.stat.bits = 0;
}
#define tag_write(p,ptr,n) do { \
if (--v.stat.bits < 0) \
{ \
*(__unaligned tag_t *)v.temp.tag_ptr = v.temp.tag_mask; \
v.temp.tag_mask = n; \
v.stat.bits = 8 * sizeof (v.temp.tag_mask) - 1; \
v.temp.tag_ptr = ptr; \
ptr += sizeof (v.temp.tag_mask); \
} \
v.temp.tag_mask = (v.temp.tag_mask << 1) + (n); \
} while (0)
#define tag_write_mask(p,ptr,n,b) do { \
if ((v.stat.bits -= (b)) < 0) \
{ \
*(__unaligned tag_t *)v.temp.tag_ptr = (v.temp.tag_mask << ((b) + v.stat.bits)) \
+ ((n) >> (-v.stat.bits)); \
v.stat.bits += 8 * sizeof (v.temp.tag_mask); \
v.temp.tag_mask = (n); \
v.temp.tag_ptr = ptr; \
ptr += sizeof (v.temp.tag_mask); \
} \
else \
v.temp.tag_mask = (v.temp.tag_mask << (b)) + (n); \
} while (0);
static void tag_write_finish (prs *p)
{
do
tag_write (p, v.temp.ptr, 1);
while (v.stat.bits != 0);
*(__unaligned tag_t *)v.temp.tag_ptr = v.temp.tag_mask;
}
#define write_lit(p,ptr,ch) do { \
tag_write (p, ptr, 0); \
*ptr++ = (ch); \
} while (0)
INLINE uchar *write_ptr (prs *p, uchar *ptr, xint offset, xint length)
{
uxint k;
--offset;
k = 2;
if (offset > 255) k = 3;
tag_write_mask (p, ptr, k, 2);
*ptr++ = (uchar) offset;
if (offset > 255) *ptr++ = (uchar) (offset >>= 8);
if (length <= 8)
{
length -= MIN_MATCH - 1;
tag_write_mask (p, ptr, 1, length);
}
else
{
tag_write_mask (p, ptr, 0, (9 - MIN_MATCH));
if ((length -= 9) < 15)
{
if (v.stat.ptr == 0)
{
v.stat.ptr = ptr;
*ptr++ = (uchar) length;
}
else
{
v.stat.ptr[0] |= length << 4;
v.stat.ptr = 0;
}
}
else
{
length -= 15;
if (v.stat.ptr == 0)
{
v.stat.ptr = ptr;
*ptr++ = 15;
}
else
{
v.stat.ptr[0] += 0xf0;
v.stat.ptr = 0;
}
*ptr++ = (uchar) length;
if (length >= 255)
{
ptr[-1] = 255;
ptr[0] = (uchar) length;
ptr[1] = (uchar) (length >>= 8);
ptr += 2;
}
}
}
return (ptr);
}
#endif
#if CODING & (CODING_DIRECT | CODING_DIRECT2)
#define write_lit(p,ptr,ch) do { \
*ptr++ = (ch); \
tag_write (p, ptr, 0); \
} while (0)
INLINE uchar *write_ptr (prs *p, uchar *ptr, int offset, int length)
{
length -= MIN_MATCH;
--offset;
#if CODING == CODING_DIRECT2
offset <<= DIRECT2_LEN_LOG;
if (length < DIRECT2_MAX_LEN)
{
offset |= length;
ptr[0] = (uchar) offset;
ptr[1] = (uchar) (offset >>= 8);
ptr += 2;
}
else
{
offset |= DIRECT2_MAX_LEN;
length -= DIRECT2_MAX_LEN;
ptr[0] = (uchar) offset;
ptr[1] = (uchar) (offset >>= 8);
ptr += 2;
if (v.stat.ptr == 0)
{
v.stat.ptr = ptr;
*ptr++ = (uchar) (length < 15 ? length : 15);
}
else
{
v.stat.ptr[0] |= (uchar) ((length < 15 ? length : 15) << 4);
v.stat.ptr = 0;
}
if ((length -= 15) >= 0)
{
*ptr++ = (uchar) length;
if (length >= 255)
{
ptr[-1] = 255;
length += DIRECT2_MAX_LEN + 15;
ptr[0] = (uchar) length;
ptr[1] = (uchar) (length >>= 8);
ptr += 2;
}
}
}
#elif CODING == CODING_DIRECT
if (v.stat.ptr == 0)
{
if (length < 7)
{
length <<= 5;
v.stat.ptr = ptr;
short_len:
ptr[0] = (uchar) length;
ptr[1] = (uchar) offset;
ptr += 2;
if (offset > 255)
{
ptr[0] = (uchar) (offset >>= 8);
ptr[-2] = (uchar) (length += 16);
ptr += 1;
}
}
else if (length < 15 + 7)
{
length += (14 << 4) - 7;
goto short_len;
}
else
{
if (offset > 255)
ptr[0] = 0xff;
else
ptr[0] = 0xef;
long_len:
ptr[1] = (uchar) (length -= (7 + 15));
ptr += 2;
if (length >= 255)
{
length += 7 + 15;
ptr[-1] = 255;
ptr[0] = (uchar) (length);
ptr[1] = (uchar) (length >>= 8);
ptr += 2;
}
*ptr++ = (uchar) offset;
if (offset > 255)
*ptr++ = (uchar) (offset >>= 8);
}
}
else
{
if (length < 7)
{
length |= v.stat.ptr[0];
*ptr++ = (uchar) offset;
if (offset > 255)
{
*ptr++ = (uchar) (offset >>= 8);
length |= 8;
}
v.stat.ptr[0] = (uchar) length;
v.stat.ptr = 0;
}
else if (length < 15 + 7)
{
length -= 7;
ptr[1] = (uchar) offset;
ptr[0] = (uchar) (length <<= 4);
if (offset > 255)
{
v.stat.ptr[0] |= 15;
v.stat.ptr = ptr;
ptr[2] = (uchar) (offset >>= 8);
ptr += 3;
}
else
{
v.stat.ptr[0] |= 7;
v.stat.ptr = ptr;
ptr += 2;
}
}
else
{
if (offset > 255)
v.stat.ptr[0] |= 15;
else
v.stat.ptr[0] |= 7;
v.stat.ptr = ptr;
ptr[0] = 15 << 4;
goto long_len;
}
}
#endif /* CODING */
tag_write (p, ptr, 1);
return (ptr);
}
#elif CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
#if CODING == CODING_HUFF_ALL
#define write_lit(p,ptr,ch) do { \
++v.stat.freq[*ptr++ = (ch)]; \
tag_write (p, ptr, 0); \
} while (0)
#else
#define write_lit(p,ptr,ch) do { \
*ptr++ = (ch); \
tag_write (p, ptr, 0); \
} while (0)
#endif
#define BIOWR(mask,bits) { \
assert (((mask) >> (bits)) == 0); \
if ((Bits -= (bits)) < 0) \
{ \
*(__unaligned bitmask2 *)Ptr1 = (bitmask2) ((Mask << (Bits + (bits))) \
+ ((mask) >> (-Bits))); \
Mask = (mask); \
Bits += sizeof (ubitmask2) * 8; \
Ptr1 = Ptr2; \
Ptr2 = (ubitmask2 *) ptr; \
ptr += sizeof (ubitmask2); \
} \
else \
Mask = (Mask << (bits)) + (mask); \
}
#if CODING == CODING_HUFF_LEN
INLINE uchar *write_ptr (prs *p, uchar *ptr, int offset, int length)
{
xint k;
++v.stat.pointers;
length -= MIN_MATCH;
--offset;
k = 0; if (offset > 255) k = 1;
if (length < MAX_LENGTH - 1)
++v.stat.freq[*ptr++ = (uchar) (k |= length << 1)];
else
{
length -= MAX_LENGTH - 1;
++v.stat.freq[ptr[0] = (uchar) (k |= (MAX_LENGTH - 1) << 1)];
ptr[1] = (uchar) length;
ptr += 2;
if (length >= 255)
{
ptr[-1] = 255;
length += MAX_LENGTH - 1;
ptr[0] = (uchar) length;
ptr[1] = (uchar) (length >>= 8);
ptr += 2;
}
}
*ptr++ = (uchar) offset;
if (offset > 255)
*ptr++ = (uchar) (offset >>= 8);
tag_write (p, ptr, 1);
return (ptr);
}
static void encode_pass2 (prs *p)
{
xint Bits;
ubitmask4 Mask;
ubitmask2 *Ptr1, *Ptr2;
tag_t bmask;
uchar *src = v.temp.beg;
uchar *ptr = v.comp.ptr;
uxint k;
Ptr1 = (ubitmask2 *) ptr; ptr += sizeof (ubitmask2);
Ptr2 = (ubitmask2 *) ptr; ptr += sizeof (ubitmask2);
Mask = 0;
Bits = 8 * sizeof (ubitmask2);
bmask = 0;
goto start;
next:
if (bmask >= 0)
{
bmask <<= 1;
copy_byte:
*ptr++ = *src++;
goto next;
}
if ((bmask <<= 1) == 0)
{
start:
*(__unaligned tag_t *)ptr = bmask = *(__unaligned tag_t *)src;
src += sizeof (tag_t);
ptr += sizeof (tag_t);
if (bmask >= 0)
{
bmask = (bmask << 1) + 1;
goto copy_byte;
}
bmask = (bmask << 1) + 1;
}
if (src >= v.temp.ptr)
goto done;
k = *src++;
assert (k < HUFF_SIZE);
BIOWR (v.stat.mask[k], v.stat.bits[k]);
if (k >= ((MAX_LENGTH - 1) << 1))
{
if ((*ptr++ = *src++) == 255)
{
ptr[0] = src[0];
ptr[1] = src[1];
src += 2;
ptr += 2;
}
}
*ptr++ = *src++;
if (k & 1) *ptr++ = *src++;
goto next;
done:
*Ptr1 = (ubitmask2) (Mask <<= Bits);
*Ptr2 = 0;
v.comp.ptr = ptr;
assert (src == v.temp.ptr);
}
#elif CODING & (CODING_HUFF_PTR | CODING_HUFF_ALL)
#define MAX_BITNO_LOG 8
#define MAX_BITNO (1 << MAX_BITNO_LOG)
static uchar bitno_table[MAX_BITNO];
static int bitno_table_initialized = 0;
static void bitno_init (void)
{
int i, k, n;
if (bitno_table_initialized)
return;
bitno_table[0] = 255;
for (i = 0; i < MAX_BITNO_LOG; ++i)
{
for (n = (k = 1<<i) << 1; k < n; ++k)
bitno_table[k] = (uchar) i;
}
bitno_table_initialized = 1;
}
static int bitno (uxint n)
{
assert (n != 0 && (n >> (MAX_BITNO_LOG*2)) == 0);
if (n >= MAX_BITNO)
return (bitno_table[n >> MAX_BITNO_LOG] + MAX_BITNO_LOG);
return (bitno_table[n]);
}
#if CODING == CODING_HUFF_ALL
#define CODING_ADJUST(n) (256 + (n))
#else
#define CODING_ADJUST(n) (n)
#endif
INLINE uchar *write_ptr (prs *p, uchar *ptr, int offset, int length)
{
xint k;
k = bitno (offset);
length -= MIN_MATCH;
offset ^= 1 << k;
v.stat.pointers += 2;
v.stat.extra += k;
k <<= MAX_LENGTH_LOG;
if (length < MAX_LENGTH - 1)
{
k |= length;
*ptr++ = (uchar) k;
++v.stat.freq[CODING_ADJUST (k)];
}
else
{
k |= MAX_LENGTH - 1;
length -= MAX_LENGTH - 1;
ptr[0] = (uchar) k;
++v.stat.freq[CODING_ADJUST (k)];
ptr[1] = (uchar) length;
ptr += 2;
if (length >= 255)
{
length += MAX_LENGTH - 1;
ptr[-1] = 255;
ptr[0] = (uchar) length;
ptr[1] = (uchar) (length >>= 8);
ptr += 2;
}
}
*ptr++ = (uchar) offset;
if (k >= (9 << MAX_LENGTH_LOG))
{
v.stat.pointers += 1;
*ptr++ = (uchar) (offset >>= 8);
}
tag_write (p, ptr, 1);
return (ptr);
}
static void encode_pass2 (prs *p)
{
xint Bits;
uxint Mask;
ubitmask2 *Ptr1, *Ptr2;
tag_t bmask;
uchar *src = v.temp.beg;
uchar *ptr = v.comp.ptr;
uxint k;
Ptr1 = (ubitmask2 *) ptr; ptr += sizeof (ubitmask2);
Ptr2 = (ubitmask2 *) ptr; ptr += sizeof (ubitmask2);
Mask = 0;
Bits = 8 * sizeof (ubitmask2);
bmask = 0;
goto start;
next:
if (bmask >= 0)
{
bmask <<= 1;
copy_byte:
#if CODING == CODING_HUFF_ALL
k = *src++;
BIOWR (v.stat.mask[k], v.stat.bits[k]);
#elif CODING == CODING_HUFF_PTR
*ptr++ = *src++;
#endif
goto next;
}
if ((bmask <<= 1) == 0)
{
start:
bmask = *(__unaligned tag_t *)src;
src += sizeof (tag_t);
#if CODING == CODING_HUFF_PTR
*(__unaligned tag_t *)ptr = bmask;
ptr += sizeof (tag_t);
#endif
if (bmask >= 0)
{
bmask = (bmask << 1) + 1;
goto copy_byte;
}
bmask = (bmask << 1) + 1;
}
if (src >= v.temp.ptr)
goto done;
k = *src++;
assert (k < HUFF_SIZE);
BIOWR (v.stat.mask[CODING_ADJUST (k)], v.stat.bits[CODING_ADJUST (k)]);
if ((k & (MAX_LENGTH - 1)) == MAX_LENGTH - 1)
{
if ((*ptr++ = *src++) == 255)
{
ptr[0] = src[0];
ptr[1] = src[1];
src += 2;
ptr += 2;
}
}
k >>= MAX_LENGTH_LOG;
{
uxint m = *src++;
if (k > 8)
m += *src++ << 8;
BIOWR (m, k);
}
goto next;
done:
#if CODING == CODING_HUFF_ALL
BIOWR (v.stat.mask[CODING_ADJUST(0)], v.stat.bits[CODING_ADJUST(0)]);
#endif
*Ptr1 = (ubitmask2) (Mask <<= Bits);
*Ptr2 = 0;
v.comp.ptr = ptr;
assert (src == v.temp.ptr);
}
#endif
/* ------------------ Create canonical Huffman code ------------------- */
/* ----------------------------- */
#define MAX_ALPHABET HUFF_SIZE
static void huffman_create_codes (huff_info *info, uxint *freq, xint n, uxint *mask, uchar *length, uxint maxbits, uchar *encoded, uxint *total)
{
huff_node
*p, *q, *r,
*first_sorted, *first_free;
xint i, k;
assert ((uxint) (n-1) <= (MAX_ALPHABET-1));
/* honestly it is easy enough to create Huffman code in-place */
/* but the use of explicit data structures makes code simpler */
/* clean everything up */
memset (length, 0, sizeof (length[0]) * n);
memset (encoded, 0, (n + 1) >> 1);
if (mask != 0 && mask != freq)
memset (mask, 0, sizeof (mask[0]) * n);
/* store frequencies */
p = info->buff;
for (i = 0; i < n; ++i)
{
if ((p->freq = freq[i]) != 0)
{
p->son[0] = p+1; p->son[1] = 0;
p->ch = (uint16) i;
++p;
}
}
/* handle simple case */
*total = 0;
if (p <= info->buff + 1)
{
if (p == info->buff) /* if no symbols do nothing */
return;
i = p[-1].ch; /* single symbol code */
mask[i] = 0;
encoded[i >> 1] = 0x11; /* two symbols has 1-bit length */
return;
}
first_free = p; /* store location of first unused node */
p[-1].son[0] = 0; /* terminate the list */
/* radix sort the list by frequency */
p = info->buff; /* head of the list */
/* initialize */
for (n = 0; n < 256; ++n)
*(info->link[n] = info->head + n) = 0;
for (i = 0; i < (BUFF_SIZE_LOG <= 16 ? 16 : 32); i += 8)
{
/* link node to the end of respective bucket */
do
{
n = (p->freq >> i) & 0xff;
info->link[n][0] = p; info->link[n] = p->son;
}
while ((p = p->son[0]) != 0);
/* merge buckets into single list */
n = 0;
while (info->head[n] == 0) ++n;
p = info->head[n]; info->head[k = n] = 0;
while (++n < 256)
{
if (info->head[n] == 0) continue;
info->link[k][0] = info->head[n]; info->link[k] = info->head + k; info->head[n] = 0;
k = n;
}
info->link[k][0] = 0; info->link[k] = info->head + k;
}
first_sorted = p; /* store head of sorted symbol's list */
restart:
assert (p == first_sorted);
q = first_free;
r = q - 1;
while (p != 0 || q != r)
{
++r;
/* select left subtree */
assert (q <= r && (p != 0 || q != r));
if (p == 0 || (q != r && p->freq > q->freq))
{
r->son[0] = q; r->freq = q->freq; ++q;
}
else
{
r->son[0] = p; r->freq = p->freq; p = p->son[0];
}
/* select right subtree */
assert (q <= r && (p != 0 || q != r));
if (p == 0 || (q != r && p->freq > q->freq))
{
r->son[1] = q; r->freq += q->freq; ++q;
}
else
{
r->son[1] = p; r->freq += p->freq; p = p->son[0];
}
}
/* evaluate codewords' length */
i = -1; /* stack pointer */
n = 0; /* current tree depth */
p = r; /* current subtree root */
for (;;)
{
while (p->son[1] != 0)
{
/* put right son into stack and set up its depth */
(info->head[++i] = p->son[1])->bits = (uint16) (++n);
(p = p->son[0])->bits = (uint16) n;
}
length[p->ch] = (uchar) n;
if (i < 0) break; /* nothing's in stack */
n = (p = info->head[i--])->bits;
}
p = first_sorted;
#if DEBUG
for (q = p; (r = q->son[0]) != 0; q = r)
assert (q->bits >= r->bits);
#endif
if (p->bits > maxbits)
{
assert (p == first_sorted);
q = p;
do
q->freq = (q->freq + 1) >> 1;
while ((q = q->son[0]) != 0);
goto restart;
}
/* now sort symbols in a stable way by increasing codeword length */
/* initialize */
memset (info->head, 0, sizeof (info->head[0]) * 32);
for (n = 0; n < 32; ++n)
info->link[n] = info->head + n;
/* link node to the end of respective bucket */
p = info->buff;
do
{
n = p->bits;
info->link[n][0] = p; info->link[n] = p->son;
}
while (++p != first_free);
/* merge buckets into single list */
n = 0;
while (info->head[n] == 0) ++n;
p = info->head[n]; k = n;
while (++n < 32)
{
if (info->head[n] == 0) continue;
info->link[k][0] = info->head[n];
k = n;
}
info->link[k][0] = 0;
#if DEBUG
for (q = p; (r = q->son[0]) != 0; q = r)
assert (r->bits > q->bits || (r->bits == q->bits && r->ch > q->ch));
#endif
/* set up code masks */
if (mask == freq)
memset (mask, 0, sizeof (mask[0]) * n);
n = 0; /* mask */
i = 1; /* bit length */
k = 1; /* first index */
do
{
/* sum a[i] * b[i] may be evaluated without multiplications */
/* using O(B) memory and O(N+B) time if 0 <= b[i] < B */
*total += freq[p->ch] * p->bits;
encoded[p->ch >> 1] |= p->bits << (p->ch & 1 ? 4 : 0);
mask[p->ch] = (n <<= p->bits - i);
i = p->bits;
++n;
}
while ((p = p->son[0]) != 0);
}
#endif /* CODING */
#define CHAIN 0
#define encode_pass1 encode0_pass1
#include "xencode.i"
#if MAX_CHAIN >= 1
#define CHAIN 1
#define encode_pass1 encode1_pass1
#define find_match find_match1
#include "xencode.i"
#endif
#if MAX_CHAIN >= 2
#define CHAIN 2
#define encode_pass1 encode2_pass1
#define find_match find_match2
#include "xencode.i"
#endif
#if MAX_CHAIN >= 3
#define CHAIN 3
#define encode_pass1 encodeN_pass1
#define find_match find_matchN
#include "xencode.i"
#endif
typedef void encode_pass1_proc (prs *p);
static void encode_pass1_progress (
prs *p,
encode_pass1_proc *encode_pass1,
XpressProgressFn *ProgressFn, // NULL or progress callback
void *ProgressContext, // user-defined context that will be passed to ProgressFn
int ProgressSize // call ProgressFn each time ProgressSize bytes processed
)
{
xint stop;
if (ProgressFn == 0)
{
encode_pass1 (p);
return;
}
stop = v.orig.stop;
for (;;)
{
if (v.orig.pos - v.orig.progress >= ProgressSize)
{
#if CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
ProgressFn (ProgressContext, v.orig.ptr);
#else
ProgressFn (ProgressContext, (v.orig.pos * 15) >> 4);
#endif
v.orig.progress = v.orig.pos;
}
v.orig.stop = stop;
if (v.orig.pos >= stop)
break;
if (stop - v.orig.progress > ProgressSize)
v.orig.stop = v.orig.progress + ProgressSize;
assert (v.orig.stop > v.orig.pos);
encode_pass1 (p);
}
}
int XPRESS_CALL XpressEncode
(
XpressEncodeStream stream,
void *comp,
int comp_size,
const void *orig,
int orig_size,
XpressProgressFn *ProgressFn, // NULL or progress callback
void *ProgressContext, // user-defined context that will be passed to ProgressFn
int ProgressSize // call ProgressFn each time ProgressSize bytes processed
)
{
#if CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
uchar huff_buff [HUFF_SIZE >> 1];
uxint huff_total;
#endif
uxint c_size;
prs *p;
xpress_info *info = (xpress_info *) stream;
encode_pass1_proc *encode_pass1;
if (info == 0 || info->magic != MAGIC_ENCODE)
return (0);
if ((unsigned) (orig_size-1) > info->max_size
|| orig_size <= MIN_SIZE
|| comp_size < MIN_SIZE
|| comp == 0
|| orig == 0)
{
return (orig_size);
}
p = info->p;
memset (&v, 0, sizeof (v));
v.temp.hash = (z_index_t *) (v.temp.ptr = info->temp);
v.chain = info->chain;
v.orig.end = (v.orig.ptr = orig) + (v.orig.size = v.orig.stop = orig_size);
v.orig.end_16 = v.orig.end - 16;
v.orig.end_3 = v.orig.end - MIN_MATCH;
v.comp.ptr = v.comp.beg = comp;
v.orig.pos = 0;
v.temp.beg = v.temp.ptr;
encode_pass1 = encode0_pass1;
if (v.chain <= 0)
memset ((void *) (&p->x.q_last[0]), 0, Q_HASH_SIZE * sizeof (p->x.q_last[0]));
#if MAX_CHAIN >= 1
else if (v.chain == 1)
{
encode_pass1 = encode1_pass1;
memset ((void *) (&p->x.z_next[0]), 0, Z_HASH_SIZE * sizeof (p->x.z_next[0]));
}
#if MAX_CHAIN >= 2
else
{
encode_pass1 = encode2_pass1;
#if MAX_CHAIN >= 3
if (v.chain >= 3)
encode_pass1 = encodeN_pass1;
#endif
memset (v.temp.hash, 0, sizeof (v.temp.hash[0]) * Z_HASH_SIZE);
z_hash_insert (p);
}
#endif
#endif
if (ProgressSize <= 0 || ProgressSize > orig_size)
ProgressSize = orig_size;
if (ProgressFn != 0)
ProgressFn (ProgressContext, v.orig.progress = 0);
#if CODING & (CODING_DIRECT | CODING_DIRECT2 | CODING_BY_BIT)
v.temp.beg = v.temp.ptr = v.comp.ptr;
tag_write_start (p);
for (;;)
{
xint rest = comp_size - (xint) (v.temp.ptr - v.comp.beg) - 2 * sizeof (tag_t);
rest -= (rest + 7) >> 3;
if (rest <= (xint) (2 * sizeof (tag_t) + 8))
goto no_compression;
if (v.orig.pos >= v.orig.size)
break;
v.orig.stop = v.orig.pos + rest;
if (v.orig.stop > v.orig.size - 8)
{
v.orig.stop = v.orig.size - 8;
if (v.orig.pos >= v.orig.stop)
break;
}
encode_pass1_progress (p, encode_pass1, ProgressFn, ProgressContext, ProgressSize);
}
#else
v.orig.stop -= 7;
tag_write_start (p);
encode_pass1_progress (p, encode_pass1, ProgressFn, ProgressContext, ProgressSize);
#endif
while (v.orig.pos < v.orig.size)
{
write_lit (p, v.temp.ptr, v.orig.ptr[v.orig.pos]);
++v.orig.pos;
}
tag_write_finish (p);
#if CODING & (CODING_DIRECT | CODING_DIRECT2 | CODING_BY_BIT)
c_size = (xint) (v.temp.ptr - v.temp.beg);
#elif CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
if (v.stat.pointers == 0)
goto no_compression;
#if CODING == CODING_HUFF_ALL
++v.stat.freq[CODING_ADJUST(0)];
#endif
huffman_create_codes (
&v.stat.info,
v.stat.freq, HUFF_SIZE,
v.stat.mask, v.stat.bits, 15, huff_buff, &huff_total);
c_size = huff_total;
#if CODING & (CODING_HUFF_PTR | CODING_HUFF_ALL)
c_size += v.stat.extra;
#endif
if (c_size == 0) c_size = 1;
c_size = (((c_size - 1) & ~(sizeof (bitmask2) * 8 - 1)) >> 3);
c_size += (int) (v.temp.ptr - v.temp.beg) - v.stat.pointers + 4 + sizeof (huff_buff);
#if CODING == CODING_HUFF_ALL
for (huff_total = 0; huff_total < 256; ++huff_total)
c_size -= v.stat.freq[huff_total];
c_size -= v.stat.masks * sizeof (tag_t);
#endif
#endif /* CODING */
if (c_size >= (uxint) comp_size)
{
no_compression:
comp_size = orig_size;
}
else
{
#if CODING & (CODING_HUFF_LEN | CODING_HUFF_PTR | CODING_HUFF_ALL)
memcpy (v.comp.ptr, huff_buff, sizeof (huff_buff));
v.comp.ptr += sizeof (huff_buff);
encode_pass2 (p);
#elif CODING & (CODING_BY_BIT | CODING_DIRECT | CODING_DIRECT2)
v.comp.ptr += c_size;
#else
#error Unknown CODING
#endif
comp_size = (int) (v.comp.ptr - v.comp.beg);
#if DEBUG
if (c_size != (uxint) comp_size)
printf ("error: c_size = %d, comp_size = %d\n", c_size, comp_size);
#endif
}
if (ProgressFn != 0)
ProgressFn (ProgressContext, orig_size);
return (comp_size);
}
#define ALIGN 32
XpressEncodeStream XPRESS_CALL XpressEncodeCreate
(int orig_size, void *context, XpressAllocFn *AllocFn, int chain)
{
xpress_info *info;
prs *p;
uchar *b;
int temp_size;
int alloc_size;
if (AllocFn == 0 || (unsigned) (orig_size-1) > (BUFF_SIZE-1))
return (0);
#if CODING & (CODING_DIRECT | CODING_DIRECT2 | CODING_BY_BIT)
temp_size = 0;
#else
temp_size = orig_size + ((orig_size + 7) >> 3);
#endif
alloc_size = sizeof (p->x.q_last[0]) * Q_HASH_SIZE;
#if MAX_CHAIN <= 0
chain = 0;
#else
if (chain > MAX_CHAIN)
chain = MAX_CHAIN;
if (chain >= 1)
{
alloc_size = sizeof (p->x.z_next[0]) * Z_HASH_SIZE;
#if MAX_CHAIN >= 2
if (chain >= 2)
{
alloc_size = sizeof (p->x.z_next[0]) * orig_size;
if (temp_size < sizeof (v.temp.hash[0]) * Z_HASH_SIZE)
temp_size = sizeof (v.temp.hash[0]) * Z_HASH_SIZE;
}
#endif
}
#endif
temp_size = (temp_size + 256 + sizeof (*p)) & ~(ALIGN-1);
alloc_size += temp_size + sizeof (*info) + ALIGN;
b = AllocFn (context, alloc_size);
if (b == 0)
return (0);
info = (xpress_info *) b;
info->max_size = orig_size - 1;
info->chain = chain;
info->magic = MAGIC_ENCODE;
info->memory = b;
b = (uchar *) (info + 1);
b += ALIGN - (((__int64) b) & (ALIGN-1));
info->p = p = ((prs *) (b + temp_size));
info->temp = b;
#if MAX_CHAIN >= 1
z_hash_map_init ();
#endif
#if CODING & (CODING_HUFF_PTR | CODING_HUFF_ALL)
bitno_init ();
#endif
return ((XpressEncodeStream) info);
}
void XPRESS_CALL XpressEncodeClose
(XpressEncodeStream stream, void *context, XpressFreeFn *FreeFn)
{
xpress_info *info = (xpress_info *) stream;
if (info != 0 && FreeFn != 0 && info->magic == MAGIC_ENCODE)
{
info->magic = 0;
FreeFn (context, info->memory);
}
}