Delphi控件源码

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bszlib.pas：源码内容

result := Z_STREAM_ERROR; { Some dumb compilers complain without this }
{$endif}
end;
function inflateSetDictionary(var z : z_stream;
dictionary : pBytef; {const array of byte}
dictLength : uInt) : int;
var
length : uInt;
begin
length := dictLength;
if (z.state = Z_NULL) or (z.state^.mode <> DICT0) then
begin
inflateSetDictionary := Z_STREAM_ERROR;
exit;
end;
if (adler32(Long(1), dictionary, dictLength) <> z.adler) then
begin
inflateSetDictionary := Z_DATA_ERROR;
exit;
end;
z.adler := Long(1);
if (length >= (uInt(1) shl z.state^.wbits)) then
begin
length := (1 shl z.state^.wbits)-1;
Inc( dictionary, dictLength - length);
end;
inflate_set_dictionary(z.state^.blocks^, dictionary^, length);
z.state^.mode := BLOCKS;
inflateSetDictionary := Z_OK;
end;
function inflateSync(var z : z_stream) : int;
const
mark : packed array[0..3] of byte = (0, 0, $ff, $ff);
var
n : uInt; { number of bytes to look at }
p : pBytef; { pointer to bytes }
m : uInt; { number of marker bytes found in a row }
r, w : uLong; { temporaries to save total_in and total_out }
begin
{ set up }
if (z.state = Z_NULL) then
begin
inflateSync := Z_STREAM_ERROR;
exit;
end;
if (z.state^.mode <> BAD) then
begin
z.state^.mode := BAD;
z.state^.sub.marker := 0;
end;
n := z.avail_in;
if (n = 0) then
begin
inflateSync := Z_BUF_ERROR;
exit;
end;
p := z.next_in;
m := z.state^.sub.marker;
{ search }
while (n <> 0) and (m < 4) do
begin
if (p^ = mark[m]) then
Inc(m)
else
if (p^ <> 0) then
m := 0
else
m := 4 - m;
Inc(p);
Dec(n);
end;
{ restore }
Inc(z.total_in, ptr2int(p) - ptr2int(z.next_in));
z.next_in := p;
z.avail_in := n;
z.state^.sub.marker := m;
{ return no joy or set up to restart on a new block }
if (m <> 4) then
begin
inflateSync := Z_DATA_ERROR;
exit;
end;
r := z.total_in;
w := z.total_out;
inflateReset(z);
z.total_in := r;
z.total_out := w;
z.state^.mode := BLOCKS;
inflateSync := Z_OK;
end;
{
returns true if inflate is currently at the end of a block generated
by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
but removes the length bytes of the resulting empty stored block. When
decompressing, PPP checks that at the end of input packet, inflate is
waiting for these length bytes.
}
function inflateSyncPoint(var z : z_stream) : int;
begin
if (z.state = Z_NULL) or (z.state^.blocks = Z_NULL) then
begin
inflateSyncPoint := Z_STREAM_ERROR;
exit;
end;
inflateSyncPoint := inflate_blocks_sync_point(z.state^.blocks^);
end;
const
{
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
include such an acknowledgment, I would appreciate that you keep this
copyright string in the executable of your product.
}
const
{ Tables for deflate from PKZIP's appnote.txt. }
cplens : Array [0..30] Of uInt { Copy lengths for literal codes 257..285 }
= (3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0);
{ actually lengths - 2; also see note #13 above about 258 }
invalid_code = 112;
cplext : Array [0..30] Of uInt { Extra bits for literal codes 257..285 }
= (0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, invalid_code, invalid_code);
cpdist : Array [0..29] Of uInt { Copy offsets for distance codes 0..29 }
= (1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
8193, 12289, 16385, 24577);
cpdext : Array [0..29] Of uInt { Extra bits for distance codes }
= (0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
12, 12, 13, 13);
{ Huffman code decoding is performed using a multi-level table lookup.
The fastest way to decode is to simply build a lookup table whose
size is determined by the longest code. However, the time it takes
to build this table can also be a factor if the data being decoded
is not very long. The most common codes are necessarily the
shortest codes, so those codes dominate the decoding time, and hence
the speed. The idea is you can have a shorter table that decodes the
shorter, more probable codes, and then point to subsidiary tables for
the longer codes. The time it costs to decode the longer codes is
then traded against the time it takes to make longer tables.
This results of this trade are in the variables lbits and dbits
below. lbits is the number of bits the first level table for literal/
length codes can decode in one step, and dbits is the same thing for
the distance codes. Subsequent tables are also less than or equal to
those sizes. These values may be adjusted either when all of the
codes are shorter than that, in which case the longest code length in
bits is used, or when the shortest code is *longer* than the requested
table size, in which case the length of the shortest code in bits is
used.
There are two different values for the two tables, since they code a
different number of possibilities each. The literal/length table
codes 286 possible values, or in a flat code, a little over eight
bits. The distance table codes 30 possible values, or a little less
than five bits, flat. The optimum values for speed end up being
about one bit more than those, so lbits is 8+1 and dbits is 5+1.
The optimum values may differ though from machine to machine, and
possibly even between compilers. Your mileage may vary. }
{ If BMAX needs to be larger than 16, then h and x[] should be uLong. }
const
BMAX = 15; { maximum bit length of any code }
{$DEFINE USE_PTR}
function huft_build(
var b : array of uIntf; { code lengths in bits (all assumed <= BMAX) }
n : uInt; { number of codes (assumed <= N_MAX) }
s : uInt; { number of simple-valued codes (0..s-1) }
const d : array of uIntf; { list of base values for non-simple codes }
{ array of word }
const e : array of uIntf; { list of extra bits for non-simple codes }
{ array of byte }
t : ppInflate_huft; { result: starting table }
var m : uIntf; { maximum lookup bits, returns actual }
var hp : array of inflate_huft; { space for trees }
var hn : uInt; { hufts used in space }
var v : array of uIntf { working area: values in order of bit length }
) : int;
{ Given a list of code lengths and a maximum table size, make a set of
tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
if the given code set is incomplete (the tables are still built in this
case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
lengths), or Z_MEM_ERROR if not enough memory. }
Var
a : uInt; { counter for codes of length k }
c : Array [0..BMAX] Of uInt; { bit length count table }
f : uInt; { i repeats in table every f entries }
g : int; { maximum code length }
h : int; { table level }
i : uInt; {register} { counter, current code }
j : uInt; {register} { counter }
k : Int; {register} { number of bits in current code }
l : int; { bits per table (returned in m) }
mask : uInt; { (1 shl w) - 1, to avoid cc -O bug on HP }
p : ^uIntf; {register} { pointer into c[], b[], or v[] }
q : pInflate_huft; { points to current table }
r : inflate_huft; { table entry for structure assignment }
u : Array [0..BMAX-1] Of pInflate_huft; { table stack }
w : int; {register} { bits before this table = (l*h) }
x : Array [0..BMAX] Of uInt; { bit offsets, then code stack }
{$IFDEF USE_PTR}
xp : puIntf; { pointer into x }
{$ELSE}
xp : uInt;
{$ENDIF}
y : int; { number of dummy codes added }
z : uInt; { number of entries in current table }
Begin
{ Generate counts for each bit length }
FillChar(c,SizeOf(c),0) ; { clear c[] }
for i := 0 to n-1 do
Inc (c[b[i]]); { assume all entries <= BMAX }
If (c[0] = n) Then { null input--all zero length codes }
Begin
t^ := pInflate_huft(NIL);
m := 0 ;
huft_build := Z_OK ;
Exit;
End ;
{ Find minimum and maximum length, bound [m] by those }
l := m;
for j:=1 To BMAX do
if (c[j] <> 0) then
break;
k := j ; { minimum code length }
if (uInt(l) < j) then
l := j;
for i := BMAX downto 1 do
if (c[i] <> 0) then
break ;
g := i ; { maximum code length }
if (uInt(l) > i) then
l := i;
m := l;
{ Adjust last length count to fill out codes, if needed }
y := 1 shl j ;
while (j < i) do
begin
Dec(y, c[j]) ;
if (y < 0) then
begin
huft_build := Z_DATA_ERROR; { bad input: more codes than bits }
exit;
end ;
Inc(j) ;
y := y shl 1
end;
Dec (y, c[i]) ;
if (y < 0) then
begin
huft_build := Z_DATA_ERROR; { bad input: more codes than bits }
exit;
end;
Inc(c[i], y);
{ Generate starting offsets into the value table FOR each length }
{$IFDEF USE_PTR}
x[1] := 0;
j := 0;
p := @c[1];
xp := @x[2];
dec(i); { note that i = g from above }
WHILE (i > 0) DO
BEGIN
inc(j, p^);
xp^ := j;
inc(p);
inc(xp);
dec(i);
END;
{$ELSE}
x[1] := 0;
j := 0 ;
for i := 1 to g do
begin
x[i] := j;
Inc(j, c[i]);
end;
{$ENDIF}
{ Make a table of values in order of bit lengths }
for i := 0 to n-1 do
begin
j := b[i];
if (j <> 0) then
begin
v[ x[j] ] := i;
Inc(x[j]);
end;
end;
n := x[g]; { set n to length of v }
{ Generate the Huffman codes and for each, make the table entries }
i := 0 ;
x[0] := 0 ; { first Huffman code is zero }
p := Addr(v) ; { grab values in bit order }
h := -1 ; { no tables yet--level -1 }
w := -l ; { bits decoded = (l*h) }
u[0] := pInflate_huft(NIL); { just to keep compilers happy }
q := pInflate_huft(NIL); { ditto }
z := 0 ; { ditto }
{ go through the bit lengths (k already is bits in shortest code) }
while (k <= g) Do
begin
a := c[k] ;
while (a<>0) Do
begin
Dec (a) ;
{ here i is the Huffman code of length k bits for value p^ }
{ make tables up to required level }
while (k > w + l) do
begin
Inc (h) ;
Inc (w, l); { add bits already decoded }
{ previous table always l bits }
{ compute minimum size table less than or equal to l bits }
{ table size upper limit }
z := g - w;
If (z > uInt(l)) Then
z := l;
{ try a k-w bit table }
j := k - w;
f := 1 shl j;
if (f > a+1) Then { too few codes for k-w bit table }
begin
Dec(f, a+1); { deduct codes from patterns left }
{$IFDEF USE_PTR}
xp := Addr(c[k]);
if (j < z) then
begin
Inc(j);
while (j < z) do
begin { try smaller tables up to z bits }
f := f shl 1;
Inc (xp) ;
If (f <= xp^) Then
break; { enough codes to use up j bits }
Dec(f, xp^); { else deduct codes from patterns }
Inc(j);
end;
end;
{$ELSE}
xp := k;
if (j < z) then
begin
Inc (j) ;
While (j < z) Do
begin { try smaller tables up to z bits }
f := f * 2;
Inc (xp) ;
if (f <= c[xp]) then
Break ; { enough codes to use up j bits }
Dec (f, c[xp]) ; { else deduct codes from patterns }
Inc (j);
end;
end;
{$ENDIF}
end;
z := 1 shl j; { table entries for j-bit table }
{ allocate new table }
if (hn + z > MANY) then { (note: doesn't matter for fixed) }
begin
huft_build := Z_MEM_ERROR; { not enough memory }
exit;
end;
q := @hp[hn];
u[h] := q;
Inc(hn, z);
{ connect to last table, if there is one }
if (h <> 0) then
begin
x[h] := i; { save pattern for backing up }
r.bits := Byte(l); { bits to dump before this table }
r.exop := Byte(j); { bits in this table }
j := i shr (w - l);
{r.base := uInt( q - u[h-1] -j);} { offset to this table }
r.base := (ptr2int(q) - ptr2int(u[h-1]) ) div sizeof(q^) - j;
huft_Ptr(u[h-1])^[j] := r; { connect to last table }
end
else
t^ := q; { first table is returned result }
end;
{ set up table entry in r }
r.bits := Byte(k - w);
{ C-code: if (p >= v + n) - see ZUTIL.PAS for comments }
if ptr2int(p)>=ptr2int(@(v[n])) then { also works under DPMI ?? }
r.exop := 128 + 64 { out of values--invalid code }
else
if (p^ < s) then
begin
if (p^ < 256) then { 256 is end-of-block code }
r.exop := 0
Else
r.exop := 32 + 64; { EOB_code; }
r.base := p^; { simple code is just the value }
Inc(p);
end
Else
begin
r.exop := Byte(e[p^-s] + 16 + 64); { non-simple--look up in lists }
r.base := d[p^-s];
Inc (p);
end ;
{ fill code-like entries with r }
f := 1 shl (k - w);
j := i shr w;
while (j < z) do
begin
huft_Ptr(q)^[j] := r;
Inc(j, f);
end;
{ backwards increment the k-bit code i }
j := 1 shl (k-1) ;
while (i and j) <> 0 do
begin
i := i xor j; { bitwise exclusive or }
j := j shr 1
end ;
i := i xor j;
{ backup over finished tables }
mask := (1 shl w) - 1; { needed on HP, cc -O bug }
while ((i and mask) <> x[h]) do
begin
Dec(h); { don't need to update q }
Dec(w, l);
mask := (1 shl w) - 1;
end;
end;
Inc(k);
end;
{ Return Z_BUF_ERROR if we were given an incomplete table }
if (y <> 0) And (g <> 1) then
huft_build := Z_BUF_ERROR
else
huft_build := Z_OK;
end; { huft_build}
function inflate_trees_bits(
var c : array of uIntf; { 19 code lengths }
var bb : uIntf; { bits tree desired/actual depth }
var tb : pinflate_huft; { bits tree result }
var hp : array of Inflate_huft; { space for trees }
var z : z_stream { for messages }
) : int;
var
r : int;
hn : uInt; { hufts used in space }
v : PuIntArray; { work area for huft_build }
begin
hn := 0;
v := PuIntArray( ZALLOC(z, 19, sizeof(uInt)) );
if (v = Z_NULL) then
begin
inflate_trees_bits := Z_MEM_ERROR;
exit;
end;
r := huft_build(c, 19, 19, cplens, cplext,
{puIntf(Z_NULL), puIntf(Z_NULL),}
@tb, bb, hp, hn, v^);
if (r = Z_DATA_ERROR) then
z.msg := 'oversubscribed dynamic bit lengths tree'
else
if (r = Z_BUF_ERROR) or (bb = 0) then
begin
z.msg := 'incomplete dynamic bit lengths tree';
r := Z_DATA_ERROR;
end;
ZFREE(z, v);
inflate_trees_bits := r;
end;
function inflate_trees_dynamic(
nl : uInt; { number of literal/length codes }
nd : uInt; { number of distance codes }
var c : Array of uIntf; { that many (total) code lengths }
var bl : uIntf; { literal desired/actual bit depth }
var bd : uIntf; { distance desired/actual bit depth }
var tl : pInflate_huft; { literal/length tree result }
var td : pInflate_huft; { distance tree result }
var hp : array of Inflate_huft; { space for trees }
var z : z_stream { for messages }
) : int;
var
r : int;
hn : uInt; { hufts used in space }
v : PuIntArray; { work area for huft_build }
begin
hn := 0;
{ allocate work area }
v := PuIntArray( ZALLOC(z, 288, sizeof(uInt)) );
if (v = Z_NULL) then
begin
inflate_trees_dynamic := Z_MEM_ERROR;
exit;
end;
{ build literal/length tree }
r := huft_build(c, nl, 257, cplens, cplext, @tl, bl, hp, hn, v^);
if (r <> Z_OK) or (bl = 0) then
begin
if (r = Z_DATA_ERROR) then
z.msg := 'oversubscribed literal/length tree'
else
if (r <> Z_MEM_ERROR) then
begin
z.msg := 'incomplete literal/length tree';
r := Z_DATA_ERROR;
end;
ZFREE(z, v);
inflate_trees_dynamic := r;
exit;
end;
{ build distance tree }
r := huft_build(puIntArray(@c[nl])^, nd, 0,
cpdist, cpdext, @td, bd, hp, hn, v^);
if (r <> Z_OK) or ((bd = 0) and (nl > 257)) then
begin
if (r = Z_DATA_ERROR) then
z.msg := 'oversubscribed literal/length tree'
else
if (r = Z_BUF_ERROR) then
begin
{$ifdef PKZIP_BUG_WORKAROUND}
r := Z_OK;
end;
{$else}
z.msg := 'incomplete literal/length tree';
r := Z_DATA_ERROR;
end
else
if (r <> Z_MEM_ERROR) then
begin
z.msg := 'empty distance tree with lengths';
r := Z_DATA_ERROR;
end;
ZFREE(z, v);
inflate_trees_dynamic := r;
exit;
{$endif}
end;
{ done }
ZFREE(z, v);
inflate_trees_dynamic := Z_OK;
end;
{$UNDEF BUILDFIXED}
{ build fixed tables only once--keep them here }
{$IFNDEF BUILDFIXED}
{ locals }
const
{$WRITEABLECONST ON}
fixed_built : Boolean = false;
{$WRITEABLECONST OFF}
FIXEDH = 544; { number of hufts used by fixed tables }
var
fixed_mem : array[0..FIXEDH-1] of inflate_huft;
fixed_bl : uInt;
fixed_bd : uInt;
fixed_tl : pInflate_huft;
fixed_td : pInflate_huft;
{$ELSE}
{ inffixed.h -- table for decoding fixed codes }
{local}
const
fixed_bl = uInt(9);
{local}
const
fixed_bd = uInt(5);
{local}
const
fixed_tl : array [0..288-1] of inflate_huft = (
Exop, { number of extra bits or operation }
bits : Byte; { number of bits in this code or subcode }
{pad : uInt;} { pad structure to a power of 2 (4 bytes for }
{ 16-bit, 8 bytes for 32-bit int's) }
base : uInt; { literal, length base, or distance base }
{ or table offset }
((96,7),256), ((0,8),80), ((0,8),16), ((84,8),115), ((82,7),31),
((0,8),112), ((0,8),48), ((0,9),192), ((80,7),10), ((0,8),96),
((0,8),32), ((0,9),160), ((0,8),0), ((0,8),128), ((0,8),64),
((0,9),224), ((80,7),6), ((0,8),88), ((0,8),24), ((0,9),144),
((83,7),59), ((0,8),120), ((0,8),56), ((0,9),208), ((81,7),17),
((0,8),104), ((0,8),40), ((0,9),176), ((0,8),8), ((0,8),136),
((0,8),72), ((0,9),240), ((80,7),4), ((0,8),84), ((0,8),20),
((85,8),227), ((83,7),43), ((0,8),116), ((0,8),52), ((0,9),200),
((81,7),13), ((0,8),100), ((0,8),36), ((0,9),168), ((0,8),4),
((0,8),132), ((0,8),68), ((0,9),232), ((80,7),8), ((0,8),92),
((0,8),28), ((0,9),152), ((84,7),83), ((0,8),124), ((0,8),60),
((0,9),216), ((82,7),23), ((0,8),108), ((0,8),44), ((0,9),184),
((0,8),12), ((0,8),140), ((0,8),76), ((0,9),248), ((80,7),3),
((0,8),82), ((0,8),18), ((85,8),163), ((83,7),35), ((0,8),114),
((0,8),50), ((0,9),196), ((81,7),11), ((0,8),98), ((0,8),34),
((0,9),164), ((0,8),2), ((0,8),130), ((0,8),66), ((0,9),228),
((80,7),7), ((0,8),90), ((0,8),26), ((0,9),148), ((84,7),67),
((0,8),122), ((0,8),58), ((0,9),212), ((82,7),19), ((0,8),106),
((0,8),42), ((0,9),180), ((0,8),10), ((0,8),138), ((0,8),74),
((0,9),244), ((80,7),5), ((0,8),86), ((0,8),22), ((192,8),0),
((83,7),51), ((0,8),118), ((0,8),54), ((0,9),204), ((81,7),15),
((0,8),102), ((0,8),38), ((0,9),172), ((0,8),6), ((0,8),134),
((0,8),70), ((0,9),236), ((80,7),9), ((0,8),94), ((0,8),30),
((0,9),156), ((84,7),99), ((0,8),126), ((0,8),62), ((0,9),220),
((82,7),27), ((0,8),110), ((0,8),46), ((0,9),188), ((0,8),14),
((0,8),142), ((0,8),78), ((0,9),252), ((96,7),256), ((0,8),81),
((0,8),17), ((85,8),131), ((82,7),31), ((0,8),113), ((0,8),49),
((0,9),194), ((80,7),10), ((0,8),97), ((0,8),33), ((0,9),162),
((0,8),1), ((0,8),129), ((0,8),65), ((0,9),226), ((80,7),6),
((0,8),89), ((0,8),25), ((0,9),146), ((83,7),59), ((0,8),121),
((0,8),57), ((0,9),210), ((81,7),17), ((0,8),105), ((0,8),41),
((0,9),178), ((0,8),9), ((0,8),137), ((0,8),73), ((0,9),242),
((80,7),4), ((0,8),85), ((0,8),21), ((80,8),258), ((83,7),43),
((0,8),117), ((0,8),53), ((0,9),202), ((81,7),13), ((0,8),101),
((0,8),37), ((0,9),170), ((0,8),5), ((0,8),133), ((0,8),69),
((0,9),234), ((80,7),8), ((0,8),93), ((0,8),29), ((0,9),154),
((84,7),83), ((0,8),125), ((0,8),61), ((0,9),218), ((82,7),23),
((0,8),109), ((0,8),45), ((0,9),186), ((0,8),13), ((0,8),141),
((0,8),77), ((0,9),250), ((80,7),3), ((0,8),83), ((0,8),19),
((85,8),195), ((83,7),35), ((0,8),115), ((0,8),51), ((0,9),198),
((81,7),11), ((0,8),99), ((0,8),35), ((0,9),166), ((0,8),3),
((0,8),131), ((0,8),67), ((0,9),230), ((80,7),7), ((0,8),91),
((0,8),27), ((0,9),150), ((84,7),67), ((0,8),123), ((0,8),59),
((0,9),214), ((82,7),19), ((0,8),107), ((0,8),43), ((0,9),182),
((0,8),11), ((0,8),139), ((0,8),75), ((0,9),246), ((80,7),5),
((0,8),87), ((0,8),23), ((192,8),0), ((83,7),51), ((0,8),119),
((0,8),55), ((0,9),206), ((81,7),15), ((0,8),103), ((0,8),39),
((0,9),174), ((0,8),7), ((0,8),135), ((0,8),71), ((0,9),238),
((80,7),9), ((0,8),95), ((0,8),31), ((0,9),158), ((84,7),99),
((0,8),127), ((0,8),63), ((0,9),222), ((82,7),27), ((0,8),111),
((0,8),47), ((0,9),190), ((0,8),15), ((0,8),143), ((0,8),79),
((0,9),254), ((96,7),256), ((0,8),80), ((0,8),16), ((84,8),115),
((82,7),31), ((0,8),112), ((0,8),48), ((0,9),193), ((80,7),10),
((0,8),96), ((0,8),32), ((0,9),161), ((0,8),0), ((0,8),128),
((0,8),64), ((0,9),225), ((80,7),6), ((0,8),88), ((0,8),24),
((0,9),145), ((83,7),59), ((0,8),120), ((0,8),56), ((0,9),209),
((81,7),17), ((0,8),104), ((0,8),40), ((0,9),177), ((0,8),8),
((0,8),136), ((0,8),72), ((0,9),241), ((80,7),4), ((0,8),84),
((0,8),20), ((85,8),227), ((83,7),43), ((0,8),116), ((0,8),52),
((0,9),201), ((81,7),13), ((0,8),100), ((0,8),36), ((0,9),169),
((0,8),4), ((0,8),132), ((0,8),68), ((0,9),233), ((80,7),8),
((0,8),92), ((0,8),28), ((0,9),153), ((84,7),83), ((0,8),124),
((0,8),60), ((0,9),217), ((82,7),23), ((0,8),108), ((0,8),44),
((0,9),185), ((0,8),12), ((0,8),140), ((0,8),76), ((0,9),249),
((80,7),3), ((0,8),82), ((0,8),18), ((85,8),163), ((83,7),35),
((0,8),114), ((0,8),50), ((0,9),197), ((81,7),11), ((0,8),98),
((0,8),34), ((0,9),165), ((0,8),2), ((0,8),130), ((0,8),66),
((0,9),229), ((80,7),7), ((0,8),90), ((0,8),26), ((0,9),149),
((84,7),67), ((0,8),122), ((0,8),58), ((0,9),213), ((82,7),19),
((0,8),106), ((0,8),42), ((0,9),181), ((0,8),10), ((0,8),138),
((0,8),74), ((0,9),245), ((80,7),5), ((0,8),86), ((0,8),22),
((192,8),0), ((83,7),51), ((0,8),118), ((0,8),54), ((0,9),205),
((81,7),15), ((0,8),102), ((0,8),38), ((0,9),173), ((0,8),6),
((0,8),134), ((0,8),70), ((0,9),237), ((80,7),9), ((0,8),94),
((0,8),30), ((0,9),157), ((84,7),99), ((0,8),126), ((0,8),62),
((0,9),221), ((82,7),27), ((0,8),110), ((0,8),46), ((0,9),189),
((0,8),14), ((0,8),142), ((0,8),78), ((0,9),253), ((96,7),256),
((0,8),81), ((0,8),17), ((85,8),131), ((82,7),31), ((0,8),113),
((0,8),49), ((0,9),195), ((80,7),10), ((0,8),97), ((0,8),33),
((0,9),163), ((0,8),1), ((0,8),129), ((0,8),65), ((0,9),227),
((80,7),6), ((0,8),89), ((0,8),25), ((0,9),147), ((83,7),59),
((0,8),121), ((0,8),57), ((0,9),211), ((81,7),17), ((0,8),105),
((0,8),41), ((0,9),179), ((0,8),9), ((0,8),137), ((0,8),73),
((0,9),243), ((80,7),4), ((0,8),85), ((0,8),21), ((80,8),258),
((83,7),43), ((0,8),117), ((0,8),53), ((0,9),203), ((81,7),13),
((0,8),101), ((0,8),37), ((0,9),171), ((0,8),5), ((0,8),133),
((0,8),69), ((0,9),235), ((80,7),8), ((0,8),93), ((0,8),29),
((0,9),155), ((84,7),83), ((0,8),125), ((0,8),61), ((0,9),219),
((82,7),23), ((0,8),109), ((0,8),45), ((0,9),187), ((0,8),13),
((0,8),141), ((0,8),77), ((0,9),251), ((80,7),3), ((0,8),83),
((0,8),19), ((85,8),195), ((83,7),35), ((0,8),115), ((0,8),51),
((0,9),199), ((81,7),11), ((0,8),99), ((0,8),35), ((0,9),167),
((0,8),3), ((0,8),131), ((0,8),67), ((0,9),231), ((80,7),7),
((0,8),91), ((0,8),27), ((0,9),151), ((84,7),67), ((0,8),123),
((0,8),59), ((0,9),215), ((82,7),19), ((0,8),107), ((0,8),43),
((0,9),183), ((0,8),11), ((0,8),139), ((0,8),75), ((0,9),247),
((80,7),5), ((0,8),87), ((0,8),23), ((192,8),0), ((83,7),51),
((0,8),119), ((0,8),55), ((0,9),207), ((81,7),15), ((0,8),103),
((0,8),39), ((0,9),175), ((0,8),7), ((0,8),135), ((0,8),71),
((0,9),239), ((80,7),9), ((0,8),95), ((0,8),31), ((0,9),159),
((84,7),99), ((0,8),127), ((0,8),63), ((0,9),223), ((82,7),27),
((0,8),111), ((0,8),47), ((0,9),191), ((0,8),15), ((0,8),143),
((0,8),79), ((0,9),255)
);
{local}
const
fixed_td : array[0..32-1] of inflate_huft = (
(Exop:80;bits:5;base:1), (Exop:87;bits:5;base:257), (Exop:83;bits:5;base:17),
(Exop:91;bits:5;base:4097), (Exop:81;bits:5;base), (Exop:89;bits:5;base:1025),
(Exop:85;bits:5;base:65), (Exop:93;bits:5;base:16385), (Exop:80;bits:5;base:3),
(Exop:88;bits:5;base:513), (Exop:84;bits:5;base:33), (Exop:92;bits:5;base:8193),
(Exop:82;bits:5;base:9), (Exop:90;bits:5;base:2049), (Exop:86;bits:5;base:129),
(Exop:192;bits:5;base:24577), (Exop:80;bits:5;base:2), (Exop:87;bits:5;base:385),
(Exop:83;bits:5;base:25), (Exop:91;bits:5;base:6145), (Exop:81;bits:5;base:7),
(Exop:89;bits:5;base:1537), (Exop:85;bits:5;base:97), (Exop:93;bits:5;base:24577),
(Exop:80;bits:5;base:4), (Exop:88;bits:5;base:769), (Exop:84;bits:5;base:49),
(Exop:92;bits:5;base:12289), (Exop:82;bits:5;base:13), (Exop:90;bits:5;base:3073),
(Exop:86;bits:5;base:193), (Exop:192;bits:5;base:24577)
);
{$ENDIF}
function inflate_trees_fixed(
var bl : uIntf; { literal desired/actual bit depth }
var bd : uIntf; { distance desired/actual bit depth }
var tl : pInflate_huft; { literal/length tree result }
var td : pInflate_huft; { distance tree result }
var z : z_stream { for memory allocation }
) : int;
type
pFixed_table = ^fixed_table;
fixed_table = array[0..288-1] of uIntf;
var
k : int; { temporary variable }
c : pFixed_table; { length list for huft_build }
v : PuIntArray; { work area for huft_build }
var
f : uInt; { number of hufts used in fixed_mem }
begin
{ build fixed tables if not already (multiple overlapped executions ok) }
if not fixed_built then
begin
f := 0;
{ allocate memory }
c := pFixed_table( ZALLOC(z, 288, sizeof(uInt)) );
if (c = Z_NULL) then
begin
inflate_trees_fixed := Z_MEM_ERROR;
exit;
end;
v := PuIntArray( ZALLOC(z, 288, sizeof(uInt)) );
if (v = Z_NULL) then
begin
ZFREE(z, c);
inflate_trees_fixed := Z_MEM_ERROR;
exit;
end;
{ literal table }
for k := 0 to Pred(144) do
c^[k] := 8;
for k := 144 to Pred(256) do
c^[k] := 9;
for k := 256 to Pred(280) do
c^[k] := 7;
for k := 280 to Pred(288) do
c^[k] := 8;
fixed_bl := 9;
huft_build(c^, 288, 257, cplens, cplext, @fixed_tl, fixed_bl,
fixed_mem, f, v^);
{ distance table }
for k := 0 to Pred(30) do
c^[k] := 5;
fixed_bd := 5;
huft_build(c^, 30, 0, cpdist, cpdext, @fixed_td, fixed_bd,
fixed_mem, f, v^);
{ done }
ZFREE(z, v);
ZFREE(z, c);
fixed_built := True;
end;
bl := fixed_bl;
bd := fixed_bd;
tl := fixed_tl;
td := fixed_td;
inflate_trees_fixed := Z_OK;
end; { inflate_trees_fixed }
{ macros for bit input with no checking and for returning unused bytes }
procedure GRABBITS(j : int);
begin
{while (k < j) do
begin
Dec(z^.avail_in);
Inc(z^.total_in);
b := b or (uLong(z^.next_in^) shl k);
Inc(z^.next_in);
Inc(k, 8);
end;}
end;
procedure DUMPBITS(j : int);
begin
{b := b shr j;
Dec(k, j);}
end;
procedure NEEDBITS(j : int);
begin
(*
while (k < j) do
begin
{NEEDBYTE;}
if (n <> 0) then
r :=Z_OK
else
begin
{UPDATE}
s.bitb := b;
s.bitk := k;
z.avail_in := n;
Inc(z.total_in, LongInt(p)-LongInt(z.next_in));
z.next_in := p;
s.write := q;
result := inflate_flush(s,z,r);
exit;
end;
Dec(n);
b := b or (uLong(p^) shl k);
Inc(p);
Inc(k, 8);
end;
*)
end;
procedure NEEDOUT;
begin
(*
if (m = 0) then
begin
{WRAP}
if (q = s.zend) and (s.read <> s.window) then
begin
q := s.window;
if LongInt(q) < LongInt(s.read) then
m := uInt(LongInt(s.read)-LongInt(q)-1)
else
m := uInt(LongInt(s.zend)-LongInt(q));
end;
if (m = 0) then
begin
{FLUSH}
s.write := q;
r := inflate_flush(s,z,r);
q := s.write;
if LongInt(q) < LongInt(s.read) then
m := uInt(LongInt(s.read)-LongInt(q)-1)
else
m := uInt(LongInt(s.zend)-LongInt(q));
{WRAP}
if (q = s.zend) and (s.read <> s.window) then
begin
q := s.window;
if LongInt(q) < LongInt(s.read) then
m := uInt(LongInt(s.read)-LongInt(q)-1)
else
m := uInt(LongInt(s.zend)-LongInt(q));
end;
if (m = 0) then
begin
{UPDATE}
s.bitb := b;
s.bitk := k;
z.avail_in := n;
Inc(z.total_in, LongInt(p)-LongInt(z.next_in));
z.next_in := p;
s.write := q;
result := inflate_flush(s,z,r);
exit;
end;
end;
end;
r := Z_OK;
*)
end;
{ copy as much as possible from the sliding window to the output area }
function inflate_flush(var s : inflate_blocks_state;
var z : z_stream;
r : int) : int;
var
n : uInt;
p : pBytef;
q : pBytef;
begin
{ local copies of source and destination pointers }
p := z.next_out;
q := s.read;
{ compute number of bytes to copy as far as end of window }
if ptr2int(q) <= ptr2int(s.write) then
n := uInt(ptr2int(s.write) - ptr2int(q))
else
n := uInt(ptr2int(s.zend) - ptr2int(q));
if (n > z.avail_out) then
n := z.avail_out;
if (n <> 0) and (r = Z_BUF_ERROR) then
r := Z_OK;
{ update counters }
Dec(z.avail_out, n);
Inc(z.total_out, n);
{ update check information }
if Assigned(s.checkfn) then
begin
s.check := s.checkfn(s.check, q, n);
z.adler := s.check;
end;
{ copy as far as end of window }
zmemcpy(p, q, n);
Inc(p, n);
Inc(q, n);
{ see if more to copy at beginning of window }
if (q = s.zend) then
begin
{ wrap pointers }
q := s.window;
if (s.write = s.zend) then
s.write := s.window;
{ compute bytes to copy }
n := uInt(ptr2int(s.write) - ptr2int(q));
if (n > z.avail_out) then
n := z.avail_out;
if (n <> 0) and (r = Z_BUF_ERROR) then
r := Z_OK;
{ update counters }
Dec( z.avail_out, n);
Inc( z.total_out, n);
{ update check information }
if Assigned(s.checkfn) then
begin
s.check := s.checkfn(s.check, q, n);
z.adler := s.check;
end;
{ copy }
zmemcpy(p, q, n);
Inc(p, n);
Inc(q, n);
end;
{ update pointers }
z.next_out := p;
s.read := q;
{ done }
inflate_flush := r;
end;
{ #define GEN_TREES_H }
{$ifndef GEN_TREES_H}
{ header created automatically with -DGEN_TREES_H }
const
DIST_CODE_LEN = 512; { see definition of array dist_code below }
{ The static literal tree. Since the bit lengths are imposed, there is no
need for the L_CODES extra codes used during heap construction. However
The codes 286 and 287 are needed to build a canonical tree (see _tr_init
below). }
type
tstatic_ltree = ARRAY[0..L_CODES+2-1] of ct_data;
const
static_ltree : tstatic_ltree = (
{ fc:(freq, code) dl:(dad,len) }
(fc:(freq: 12);dl:(len: 8)), (fc:(freq:140);dl:(len: 8)), (fc:(freq: 76);dl:(len: 8)),
(fc:(freq:204);dl:(len: 8)), (fc:(freq: 44);dl:(len: 8)), (fc:(freq:172);dl:(len: 8)),
(fc:(freq:108);dl:(len: 8)), (fc:(freq:236);dl:(len: 8)), (fc:(freq: 28);dl:(len: 8)),
(fc:(freq:156);dl:(len: 8)), (fc:(freq: 92);dl:(len: 8)), (fc:(freq:220);dl:(len: 8)),
(fc:(freq: 60);dl:(len: 8)), (fc:(freq:188);dl:(len: 8)), (fc:(freq:124);dl:(len: 8)),
(fc:(freq:252);dl:(len: 8)), (fc:(freq: 2);dl:(len: 8)), (fc:(freq:130);dl:(len: 8)),
(fc:(freq: 66);dl:(len: 8)), (fc:(freq:194);dl:(len: 8)), (fc:(freq: 34);dl:(len: 8)),
(fc:(freq:162);dl:(len: 8)), (fc:(freq: 98);dl:(len: 8)), (fc:(freq:226);dl:(len: 8)),
(fc:(freq: 18);dl:(len: 8)), (fc:(freq:146);dl:(len: 8)), (fc:(freq: 82);dl:(len: 8)),
(fc:(freq:210);dl:(len: 8)), (fc:(freq: 50);dl:(len: 8)), (fc:(freq:178);dl:(len: 8)),
(fc:(freq:114);dl:(len: 8)), (fc:(freq:242);dl:(len: 8)), (fc:(freq: 10);dl:(len: 8)),
(fc:(freq:138);dl:(len: 8)), (fc:(freq: 74);dl:(len: 8)), (fc:(freq:202);dl:(len: 8)),
(fc:(freq: 42);dl:(len: 8)), (fc:(freq:170);dl:(len: 8)), (fc:(freq:106);dl:(len: 8)),
(fc:(freq:234);dl:(len: 8)), (fc:(freq: 26);dl:(len: 8)), (fc:(freq:154);dl:(len: 8)),
(fc:(freq: 90);dl:(len: 8)), (fc:(freq:218);dl:(len: 8)), (fc:(freq: 58);dl:(len: 8)),
(fc:(freq:186);dl:(len: 8)), (fc:(freq:122);dl:(len: 8)), (fc:(freq:250);dl:(len: 8)),
(fc:(freq: 6);dl:(len: 8)), (fc:(freq:134);dl:(len: 8)), (fc:(freq: 70);dl:(len: 8)),
(fc:(freq:198);dl:(len: 8)), (fc:(freq: 38);dl:(len: 8)), (fc:(freq:166);dl:(len: 8)),
(fc:(freq:102);dl:(len: 8)), (fc:(freq:230);dl:(len: 8)), (fc:(freq: 22);dl:(len: 8)),
(fc:(freq:150);dl:(len: 8)), (fc:(freq: 86);dl:(len: 8)), (fc:(freq:214);dl:(len: 8)),
(fc:(freq: 54);dl:(len: 8)), (fc:(freq:182);dl:(len: 8)), (fc:(freq:118);dl:(len: 8)),
(fc:(freq:246);dl:(len: 8)), (fc:(freq: 14);dl:(len: 8)), (fc:(freq:142);dl:(len: 8)),
(fc:(freq: 78);dl:(len: 8)), (fc:(freq:206);dl:(len: 8)), (fc:(freq: 46);dl:(len: 8)),
(fc:(freq:174);dl:(len: 8)), (fc:(freq:110);dl:(len: 8)), (fc:(freq:238);dl:(len: 8)),
(fc:(freq: 30);dl:(len: 8)), (fc:(freq:158);dl:(len: 8)), (fc:(freq: 94);dl:(len: 8)),
(fc:(freq:222);dl:(len: 8)), (fc:(freq: 62);dl:(len: 8)), (fc:(freq:190);dl:(len: 8)),
(fc:(freq:126);dl:(len: 8)), (fc:(freq:254);dl:(len: 8)), (fc:(freq: 1);dl:(len: 8)),
(fc:(freq:129);dl:(len: 8)), (fc:(freq: 65);dl:(len: 8)), (fc:(freq:193);dl:(len: 8)),
(fc:(freq: 33);dl:(len: 8)), (fc:(freq:161);dl:(len: 8)), (fc:(freq: 97);dl:(len: 8)),
(fc:(freq:225);dl:(len: 8)), (fc:(freq: 17);dl:(len: 8)), (fc:(freq:145);dl:(len: 8)),
(fc:(freq: 81);dl:(len: 8)), (fc:(freq:209);dl:(len: 8)), (fc:(freq: 49);dl:(len: 8)),
(fc:(freq:177);dl:(len: 8)), (fc:(freq:113);dl:(len: 8)), (fc:(freq:241);dl:(len: 8)),
(fc:(freq: 9);dl:(len: 8)), (fc:(freq:137);dl:(len: 8)), (fc:(freq: 73);dl:(len: 8)),
(fc:(freq:201);dl:(len: 8)), (fc:(freq: 41);dl:(len: 8)), (fc:(freq:169);dl:(len: 8)),
(fc:(freq:105);dl:(len: 8)), (fc:(freq:233);dl:(len: 8)), (fc:(freq: 25);dl:(len: 8)),
(fc:(freq:153);dl:(len: 8)), (fc:(freq: 89);dl:(len: 8)), (fc:(freq:217);dl:(len: 8)),
(fc:(freq: 57);dl:(len: 8)), (fc:(freq:185);dl:(len: 8)), (fc:(freq:121);dl:(len: 8)),
(fc:(freq:249);dl:(len: 8)), (fc:(freq: 5);dl:(len: 8)), (fc:(freq:133);dl:(len: 8)),
(fc:(freq: 69);dl:(len: 8)), (fc:(freq:197);dl:(len: 8)), (fc:(freq: 37);dl:(len: 8)),
(fc:(freq:165);dl:(len: 8)), (fc:(freq:101);dl:(len: 8)), (fc:(freq:229);dl:(len: 8)),
(fc:(freq: 21);dl:(len: 8)), (fc:(freq:149);dl:(len: 8)), (fc:(freq: 85);dl:(len: 8)),
(fc:(freq:213);dl:(len: 8)), (fc:(freq: 53);dl:(len: 8)), (fc:(freq:181);dl:(len: 8)),
(fc:(freq:117);dl:(len: 8)), (fc:(freq:245);dl:(len: 8)), (fc:(freq: 13);dl:(len: 8)),
(fc:(freq:141);dl:(len: 8)), (fc:(freq: 77);dl:(len: 8)), (fc:(freq:205);dl:(len: 8)),
(fc:(freq: 45);dl:(len: 8)), (fc:(freq:173);dl:(len: 8)), (fc:(freq:109);dl:(len: 8)),
(fc:(freq:237);dl:(len: 8)), (fc:(freq: 29);dl:(len: 8)), (fc:(freq:157);dl:(len: 8)),
(fc:(freq: 93);dl:(len: 8)), (fc:(freq:221);dl:(len: 8)), (fc:(freq: 61);dl:(len: 8)),
(fc:(freq:189);dl:(len: 8)), (fc:(freq:125);dl:(len: 8)), (fc:(freq:253);dl:(len: 8)),
(fc:(freq: 19);dl:(len: 9)), (fc:(freq:275);dl:(len: 9)), (fc:(freq:147);dl:(len: 9)),
(fc:(freq:403);dl:(len: 9)), (fc:(freq: 83);dl:(len: 9)), (fc:(freq:339);dl:(len: 9)),
(fc:(freq:211);dl:(len: 9)), (fc:(freq:467);dl:(len: 9)), (fc:(freq: 51);dl:(len: 9)),
(fc:(freq:307);dl:(len: 9)), (fc:(freq:179);dl:(len: 9)), (fc:(freq:435);dl:(len: 9)),
(fc:(freq:115);dl:(len: 9)), (fc:(freq:371);dl:(len: 9)), (fc:(freq:243);dl:(len: 9)),
(fc:(freq:499);dl:(len: 9)), (fc:(freq: 11);dl:(len: 9)), (fc:(freq:267);dl:(len: 9)),
(fc:(freq:139);dl:(len: 9)), (fc:(freq:395);dl:(len: 9)), (fc:(freq: 75);dl:(len: 9)),
(fc:(freq:331);dl:(len: 9)), (fc:(freq:203);dl:(len: 9)), (fc:(freq:459);dl:(len: 9)),
(fc:(freq: 43);dl:(len: 9)), (fc:(freq:299);dl:(len: 9)), (fc:(freq:171);dl:(len: 9)),
(fc:(freq:427);dl:(len: 9)), (fc:(freq:107);dl:(len: 9)), (fc:(freq:363);dl:(len: 9)),
(fc:(freq:235);dl:(len: 9)), (fc:(freq:491);dl:(len: 9)), (fc:(freq: 27);dl:(len: 9)),
(fc:(freq:283);dl:(len: 9)), (fc:(freq:155);dl:(len: 9)), (fc:(freq:411);dl:(len: 9)),
(fc:(freq: 91);dl:(len: 9)), (fc:(freq:347);dl:(len: 9)), (fc:(freq:219);dl:(len: 9)),
(fc:(freq:475);dl:(len: 9)), (fc:(freq: 59);dl:(len: 9)), (fc:(freq:315);dl:(len: 9)),
(fc:(freq:187);dl:(len: 9)), (fc:(freq:443);dl:(len: 9)), (fc:(freq:123);dl:(len: 9)),
(fc:(freq:379);dl:(len: 9)), (fc:(freq:251);dl:(len: 9)), (fc:(freq:507);dl:(len: 9)),
(fc:(freq: 7);dl:(len: 9)), (fc:(freq:263);dl:(len: 9)), (fc:(freq:135);dl:(len: 9)),
(fc:(freq:391);dl:(len: 9)), (fc:(freq: 71);dl:(len: 9)), (fc:(freq:327);dl:(len: 9)),
(fc:(freq:199);dl:(len: 9)), (fc:(freq:455);dl:(len: 9)), (fc:(freq: 39);dl:(len: 9)),
(fc:(freq:295);dl:(len: 9)), (fc:(freq:167);dl:(len: 9)), (fc:(freq:423);dl:(len: 9)),
(fc:(freq:103);dl:(len: 9)), (fc:(freq:359);dl:(len: 9)), (fc:(freq:231);dl:(len: 9)),
(fc:(freq:487);dl:(len: 9)), (fc:(freq: 23);dl:(len: 9)), (fc:(freq:279);dl:(len: 9)),
(fc:(freq:151);dl:(len: 9)), (fc:(freq:407);dl:(len: 9)), (fc:(freq: 87);dl:(len: 9)),
(fc:(freq:343);dl:(len: 9)), (fc:(freq:215);dl:(len: 9)), (fc:(freq:471);dl:(len: 9)),
(fc:(freq: 55);dl:(len: 9)), (fc:(freq:311);dl:(len: 9)), (fc:(freq:183);dl:(len: 9)),
(fc:(freq:439);dl:(len: 9)), (fc:(freq:119);dl:(len: 9)), (fc:(freq:375);dl:(len: 9)),
(fc:(freq:247);dl:(len: 9)), (fc:(freq:503);dl:(len: 9)), (fc:(freq: 15);dl:(len: 9)),
(fc:(freq:271);dl:(len: 9)), (fc:(freq:143);dl:(len: 9)), (fc:(freq:399);dl:(len: 9)),
(fc:(freq: 79);dl:(len: 9)), (fc:(freq:335);dl:(len: 9)), (fc:(freq:207);dl:(len: 9)),
(fc:(freq:463);dl:(len: 9)), (fc:(freq: 47);dl:(len: 9)), (fc:(freq:303);dl:(len: 9)),
(fc:(freq:175);dl:(len: 9)), (fc:(freq:431);dl:(len: 9)), (fc:(freq:111);dl:(len: 9)),
(fc:(freq:367);dl:(len: 9)), (fc:(freq:239);dl:(len: 9)), (fc:(freq:495);dl:(len: 9)),
(fc:(freq: 31);dl:(len: 9)), (fc:(freq:287);dl:(len: 9)), (fc:(freq:159);dl:(len: 9)),
(fc:(freq:415);dl:(len: 9)), (fc:(freq: 95);dl:(len: 9)), (fc:(freq:351);dl:(len: 9)),
(fc:(freq:223);dl:(len: 9)), (fc:(freq:479);dl:(len: 9)), (fc:(freq: 63);dl:(len: 9)),
(fc:(freq:319);dl:(len: 9)), (fc:(freq:191);dl:(len: 9)), (fc:(freq:447);dl:(len: 9)),
(fc:(freq:127);dl:(len: 9)), (fc:(freq:383);dl:(len: 9)), (fc:(freq:255);dl:(len: 9)),
(fc:(freq:511);dl:(len: 9)), (fc:(freq: 0);dl:(len: 7)), (fc:(freq: 64);dl:(len: 7)),
(fc:(freq: 32);dl:(len: 7)), (fc:(freq: 96);dl:(len: 7)), (fc:(freq: 16);dl:(len: 7)),
(fc:(freq: 80);dl:(len: 7)), (fc:(freq: 48);dl:(len: 7)), (fc:(freq:112);dl:(len: 7)),
(fc:(freq: 8);dl:(len: 7)), (fc:(freq: 72);dl:(len: 7)), (fc:(freq: 40);dl:(len: 7)),
(fc:(freq:104);dl:(len: 7)), (fc:(freq: 24);dl:(len: 7)), (fc:(freq: 88);dl:(len: 7)),
(fc:(freq: 56);dl:(len: 7)), (fc:(freq:120);dl:(len: 7)), (fc:(freq: 4);dl:(len: 7)),
(fc:(freq: 68);dl:(len: 7)), (fc:(freq: 36);dl:(len: 7)), (fc:(freq:100);dl:(len: 7)),
(fc:(freq: 20);dl:(len: 7)), (fc:(freq: 84);dl:(len: 7)), (fc:(freq: 52);dl:(len: 7)),
(fc:(freq:116);dl:(len: 7)), (fc:(freq: 3);dl:(len: 8)), (fc:(freq:131);dl:(len: 8)),
(fc:(freq: 67);dl:(len: 8)), (fc:(freq:195);dl:(len: 8)), (fc:(freq: 35);dl:(len: 8)),
(fc:(freq:163);dl:(len: 8)), (fc:(freq: 99);dl:(len: 8)), (fc:(freq:227);dl:(len: 8))
);
type
tstatic_dtree = array[0..D_CODES-1] of ct_data;
{ The static distance tree. (Actually a trivial tree since all lens use
5 bits.) }
const
static_dtree : tstatic_dtree = (
(fc:(freq: 0); dl:(len:5)), (fc:(freq:16); dl:(len:5)), (fc:(freq: 8); dl:(len:5)),
(fc:(freq:24); dl:(len:5)), (fc:(freq: 4); dl:(len:5)), (fc:(freq:20); dl:(len:5)),
(fc:(freq:12); dl:(len:5)), (fc:(freq:28); dl:(len:5)), (fc:(freq: 2); dl:(len:5)),
(fc:(freq:18); dl:(len:5)), (fc:(freq:10); dl:(len:5)), (fc:(freq:26); dl:(len:5)),
(fc:(freq: 6); dl:(len:5)), (fc:(freq:22); dl:(len:5)), (fc:(freq:14); dl:(len:5)),
(fc:(freq:30); dl:(len:5)), (fc:(freq: 1); dl:(len:5)), (fc:(freq:17); dl:(len:5)),
(fc:(freq: 9); dl:(len:5)), (fc:(freq:25); dl:(len:5)), (fc:(freq: 5); dl:(len:5)),
(fc:(freq:21); dl:(len:5)), (fc:(freq:13); dl:(len:5)), (fc:(freq:29); dl:(len:5)),
(fc:(freq: 3); dl:(len:5)), (fc:(freq:19); dl:(len:5)), (fc:(freq:11); dl:(len:5)),
(fc:(freq:27); dl:(len:5)), (fc:(freq: 7); dl:(len:5)), (fc:(freq:23); dl:(len:5))
);
{ Distance codes. The first 256 values correspond to the distances
3 .. 258, the last 256 values correspond to the top 8 bits of
the 15 bit distances. }
_dist_code : array[0..DIST_CODE_LEN-1] of uch = (
0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
);
{ length code for each normalized match length (0 == MIN_MATCH) }
_length_code : array[0..MAX_MATCH-MIN_MATCH+1-1] of uch = (
0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
);
{ First normalized length for each code (0 = MIN_MATCH) }
base_length : array[0..LENGTH_CODES-1] of int = (
0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
64, 80, 96, 112, 128, 160, 192, 224, 0
);
{ First normalized distance for each code (0 = distance of 1) }
base_dist : array[0..D_CODES-1] of int = (
0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
);
{$endif}
{ ===========================================================================
Constants }
const
MAX_BL_BITS = 7;
{ Bit length codes must not exceed MAX_BL_BITS bits }
const
END_BLOCK = 256;
{ end of block literal code }
const
REP_3_6 = 16;
{ repeat previous bit length 3-6 times (2 bits of repeat count) }
const
REPZ_3_10 = 17;
{ repeat a zero length 3-10 times (3 bits of repeat count) }
const
REPZ_11_138 = 18;
{ repeat a zero length 11-138 times (7 bits of repeat count) }
{local}
const
extra_lbits : array[0..LENGTH_CODES-1] of int
{ extra bits for each length code }
= (0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0);
{local}
const
extra_dbits : array[0..D_CODES-1] of int
{ extra bits for each distance code }
= (0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13);
{local}
const
extra_blbits : array[0..BL_CODES-1] of int { extra bits for each bit length code }
= (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7);
{local}
const
bl_order : array[0..BL_CODES-1] of uch
= (16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15);
{ The lengths of the bit length codes are sent in order of decreasing
probability, to avoid transmitting the lengths for unused bit length codes.
}
const
Buf_size = (8 * 2*sizeof(char));
{ Number of bits used within bi_buf. (bi_buf might be implemented on
more than 16 bits on some systems.) }
{ ===========================================================================
Local data. These are initialized only once. }
{$ifdef GEN_TREES_H)}
{ non ANSI compilers may not accept trees.h }
const
DIST_CODE_LEN = 512; { see definition of array dist_code below }
{local}
var
static_ltree : array[0..L_CODES+2-1] of ct_data;
{ The static literal tree. Since the bit lengths are imposed, there is no
need for the L_CODES extra codes used during heap construction. However
The codes 286 and 287 are needed to build a canonical tree (see _tr_init
below). }
{local}
static_dtree : array[0..D_CODES-1] of ct_data;
{ The static distance tree. (Actually a trivial tree since all codes use
5 bits.) }
_dist_code : array[0..DIST_CODE_LEN-1] of uch;
{ Distance codes. The first 256 values correspond to the distances
3 .. 258, the last 256 values correspond to the top 8 bits of
the 15 bit distances. }
_length_code : array[0..MAX_MATCH-MIN_MATCH+1-1] of uch;
{ length code for each normalized match length (0 == MIN_MATCH) }
{local}
base_length : array[0..LENGTH_CODES-1] of int;
{ First normalized length for each code (0 = MIN_MATCH) }
{local}
base_dist : array[0..D_CODES-1] of int;
{ First normalized distance for each code (0 = distance of 1) }
{$endif} { GEN_TREES_H }
{local}
const
static_l_desc : static_tree_desc =
(static_tree: {tree_ptr}(@(static_ltree)); { pointer to array of ct_data }
extra_bits: {pzIntfArray}(@(extra_lbits)); { pointer to array of int }
extra_base: LITERALS+1;
elems: L_CODES;
max_length: MAX_BITS);
{local}
const
static_d_desc : static_tree_desc =
(static_tree: {tree_ptr}(@(static_dtree));
extra_bits: {pzIntfArray}(@(extra_dbits));
extra_base : 0;
elems: D_CODES;
max_length: MAX_BITS);
{local}
const
static_bl_desc : static_tree_desc =
(static_tree: {tree_ptr}(NIL);
extra_bits: {pzIntfArray}@(extra_blbits);
extra_base : 0;
elems: BL_CODES;
max_length: MAX_BL_BITS);
(* ===========================================================================
Local (static) routines in this file. }
procedure tr_static_init;
procedure init_block(var deflate_state);
procedure pqdownheap(var s : deflate_state;
var tree : ct_data;
k : int);
procedure gen_bitlen(var s : deflate_state;
var desc : tree_desc);
procedure gen_codes(var tree : ct_data;
max_code : int;
bl_count : pushf);
procedure build_tree(var s : deflate_state;
var desc : tree_desc);
procedure scan_tree(var s : deflate_state;
var tree : ct_data;
max_code : int);
procedure send_tree(var s : deflate_state;
var tree : ct_data;
max_code : int);
function build_bl_tree(var deflate_state) : int;
procedure send_all_trees(var deflate_state;
lcodes : int;
dcodes : int;
blcodes : int);
procedure compress_block(var s : deflate_state;
var ltree : ct_data;
var dtree : ct_data);
procedure set_data_type(var s : deflate_state);
function bi_reverse(value : unsigned;
length : int) : unsigned;
procedure bi_windup(var deflate_state);
procedure bi_flush(var deflate_state);
procedure copy_block(var deflate_state;
buf : pcharf;
len : unsigned;
header : int);
*)
{$ifdef GEN_TREES_H}
{local}
procedure gen_trees_header;
{$endif}
(*
{ ===========================================================================
Output a short LSB first on the stream.
IN assertion: there is enough room in pendingBuf. }
macro put_short(s, w)
begin
{put_byte(s, (uch)((w) & 0xff));}
s.pending_buf^[s.pending] := uch((w) and $ff);
Inc(s.pending);
{put_byte(s, (uch)((ush)(w) >> 8));}
s.pending_buf^[s.pending] := uch(ush(w) shr 8);;
Inc(s.pending);
end
*)
{ ===========================================================================
Send a value on a given number of bits.
IN assertion: length <= 16 and value fits in length bits. }
{local}
procedure send_bits(var s : deflate_state;
value : int; { value to send }
length : int); { number of bits }
begin
{$ifdef DEBUG}
Tracevv(' l '+IntToStr(length)+ ' v '+IntToStr(value));
Assert((length > 0) and (length <= 15), 'invalid length');
Inc(s.bits_sent, ulg(length));
{$ENDIF}
{ If not enough room in bi_buf, use (valid) bits from bi_buf and
(16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
unused bits in value. }
{$IFOPT Q+} {$Q-} {$DEFINE NoOverflowCheck} {$ENDIF}
{$IFOPT R+} {$R-} {$DEFINE NoRangeCheck} {$ENDIF}
if (s.bi_valid > int(Buf_size) - length) then
begin
s.bi_buf := s.bi_buf or int(value shl s.bi_valid);
{put_short(s, s.bi_buf);}
s.pending_buf^[s.pending] := uch(s.bi_buf and $ff);
Inc(s.pending);
s.pending_buf^[s.pending] := uch(ush(s.bi_buf) shr 8);;
Inc(s.pending);
s.bi_buf := ush(value) shr (Buf_size - s.bi_valid);
Inc(s.bi_valid, length - Buf_size);
end
else
begin
s.bi_buf := s.bi_buf or int(value shl s.bi_valid);
Inc(s.bi_valid, length);
end;
{$IFDEF NoOverflowCheck} {$Q+} {$UNDEF NoOverflowCheck} {$ENDIF}
{$IFDEF NoRangeCheck} {$Q+} {$UNDEF NoRangeCheck} {$ENDIF}
end;
{ ===========================================================================
Reverse the first len bits of a code, using straightforward code (a faster
method would use a table)
IN assertion: 1 <= len <= 15 }
{local}
function bi_reverse(code : unsigned; { the value to invert }
len : int) : unsigned; { its bit length }
var
res : unsigned; {register}
begin
res := 0;
repeat
res := res or (code and 1);
code := code shr 1;
res := res shl 1;
Dec(len);
until (len <= 0);
bi_reverse := res shr 1;
end;
{ ===========================================================================
Generate the codes for a given tree and bit counts (which need not be
optimal).
IN assertion: the array bl_count contains the bit length statistics for
the given tree and the field len is set for all tree elements.
OUT assertion: the field code is set for all tree elements of non
zero code length. }
{local}
procedure gen_codes(tree : tree_ptr; { the tree to decorate }
max_code : int; { largest code with non zero frequency }
var bl_count : array of ushf); { number of codes at each bit length }
var
next_code : array[0..MAX_BITS+1-1] of ush; { next code value for each bit length }
code : ush; { running code value }
bits : int; { bit index }
n : int; { code index }
var
len : int;
begin
code := 0;
{ The distribution counts are first used to generate the code values
without bit reversal. }
for bits := 1 to MAX_BITS do
begin
code := ((code + bl_count[bits-1]) shl 1);
next_code[bits] := code;
end;
{ Check that the bit counts in bl_count are consistent. The last code
must be all ones. }
{$IFDEF DEBUG}
Assert (code + bl_count[MAX_BITS]-1 = (1 shl MAX_BITS)-1,
'inconsistent bit counts');
Tracev(#13'gen_codes: max_code '+IntToStr(max_code));
{$ENDIF}
for n := 0 to max_code do
begin
len := tree^[n].dl.Len;
if (len = 0) then
continue;
{ Now reverse the bits }
tree^[n].fc.Code := bi_reverse(next_code[len], len);
Inc(next_code[len]);
{$ifdef DEBUG}
if (n>31) and (n<128) then
Tracecv(tree <> tree_ptr(@static_ltree),
(^M'n #'+IntToStr(n)+' '+char(n)+' l '+IntToStr(len)+' c '+
IntToStr(tree^[n].fc.Code)+' ('+IntToStr(next_code[len]-1)+')'))
else
Tracecv(tree <> tree_ptr(@static_ltree),
(^M'n #'+IntToStr(n)+' l '+IntToStr(len)+' c '+
IntToStr(tree^[n].fc.Code)+' ('+IntToStr(next_code[len]-1)+')'));
{$ENDIF}
end;
end;
{ ===========================================================================
Genererate the file trees.h describing the static trees. }
{$ifdef GEN_TREES_H}
macro SEPARATOR(i, last, width)
if (i) = (last) then
( ^M');'^M^M
else
if (i) mod (width) = (width)-1 then
','^M
else
', '
procedure gen_trees_header;
var
header : system.text;
i : int;
begin
system.assign(header, 'trees.inc');
{$I-}
ReWrite(header);
{$I+}
Assert (IOresult <> 0, 'Can''t open trees.h');
WriteLn(header,
'{ header created automatically with -DGEN_TREES_H }'^M);
WriteLn(header, 'local const ct_data static_ltree[L_CODES+2] := (');
for i := 0 to L_CODES+2-1 do
begin
WriteLn(header, '((%3u),(%3u))%s', static_ltree[i].Code,
static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
end;
WriteLn(header, 'local const ct_data static_dtree[D_CODES] := (');
for i := 0 to D_CODES-1 do
begin
WriteLn(header, '((%2u),(%2u))%s', static_dtree[i].Code,
static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
end;
WriteLn(header, 'const uch _dist_code[DIST_CODE_LEN] := (');
for i := 0 to DIST_CODE_LEN-1 do
begin
WriteLn(header, '%2u%s', _dist_code[i],
SEPARATOR(i, DIST_CODE_LEN-1, 20));
end;
WriteLn(header, 'const uch _length_code[MAX_MATCH-MIN_MATCH+1]= (');
for i := 0 to MAX_MATCH-MIN_MATCH+1-1 do
begin
WriteLn(header, '%2u%s', _length_code[i],
SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
end;
WriteLn(header, 'local const int base_length[LENGTH_CODES] := (');
for i := 0 to LENGTH_CODES-1 do
begin
WriteLn(header, '%1u%s', base_length[i],
SEPARATOR(i, LENGTH_CODES-1, 20));
end;
WriteLn(header, 'local const int base_dist[D_CODES] := (');
for i := 0 to D_CODES-1 do
begin
WriteLn(header, '%5u%s', base_dist[i],
SEPARATOR(i, D_CODES-1, 10));
end;
close(header);
end;
{$endif} { GEN_TREES_H }
{ ===========================================================================
Initialize the various 'constant' tables. }
{local}
procedure tr_static_init;
{$ifdef GEN_TREES_H}
const
static_init_done : boolean = FALSE;
var
n : int; { iterates over tree elements }
bits : int; { bit counter }
length : int; { length value }
code : int; { code value }
dist : int; { distance index }
bl_count : array[0..MAX_BITS+1-1] of ush;
{ number of codes at each bit length for an optimal tree }
begin
if (static_init_done) then
exit;
{ Initialize the mapping length (0..255) -> length code (0..28) }
length := 0;
for code := 0 to LENGTH_CODES-1-1 do
begin
base_length[code] := length;
for n := 0 to (1 shl extra_lbits[code])-1 do
begin
_length_code[length] := uch(code);
Inc(length);
end;
end;
Assert (length = 256, 'tr_static_init: length <> 256');
{ Note that the length 255 (match length 258) can be represented
in two different ways: code 284 + 5 bits or code 285, so we
overwrite length_code[255] to use the best encoding: }
_length_code[length-1] := uch(code);
{ Initialize the mapping dist (0..32K) -> dist code (0..29) }
dist := 0;
for code := 0 to 16-1 do
begin
base_dist[code] := dist;
for n := 0 to (1 shl extra_dbits[code])-1 do
begin
_dist_code[dist] := uch(code);
Inc(dist);
end;
end;
Assert (dist = 256, 'tr_static_init: dist <> 256');
dist := dist shr 7; { from now on, all distances are divided by 128 }
for code := 16 to D_CODES-1 do
begin
base_dist[code] := dist shl 7;
for n := 0 to (1 shl (extra_dbits[code]-7))-1 do
begin
_dist_code[256 + dist] := uch(code);
Inc(dist);
end;
end;
Assert (dist = 256, 'tr_static_init: 256+dist <> 512');
{ Construct the codes of the static literal tree }
for bits := 0 to MAX_BITS do
bl_count[bits] := 0;
n := 0;
while (n <= 143) do
begin
static_ltree[n].dl.Len := 8;
Inc(n);
Inc(bl_count[8]);
end;
while (n <= 255) do
begin
static_ltree[n].dl.Len := 9;
Inc(n);
Inc(bl_count[9]);
end;
while (n <= 279) do
begin
static_ltree[n].dl.Len := 7;
Inc(n);
Inc(bl_count[7]);
end;
while (n <= 287) do
begin
static_ltree[n].dl.Len := 8;
Inc(n);
Inc(bl_count[8]);
end;
{ Codes 286 and 287 do not exist, but we must include them in the
tree construction to get a canonical Huffman tree (longest code
all ones) }
gen_codes(tree_ptr(@static_ltree), L_CODES+1, bl_count);
{ The static distance tree is trivial: }
for n := 0 to D_CODES-1 do
begin
static_dtree[n].dl.Len := 5;
static_dtree[n].fc.Code := bi_reverse(unsigned(n), 5);
end;
static_init_done := TRUE;
gen_trees_header; { save to include file }
{$else}
begin
{$endif} { GEN_TREES_H) }
end;
{ ===========================================================================
Initialize a new block. }
{local}
procedure init_block(var s : deflate_state);
var
n : int; { iterates over tree elements }
begin
{ Initialize the trees. }
for n := 0 to L_CODES-1 do
s.dyn_ltree[n].fc.Freq := 0;
for n := 0 to D_CODES-1 do
s.dyn_dtree[n].fc.Freq := 0;
for n := 0 to BL_CODES-1 do
s.bl_tree[n].fc.Freq := 0;
s.dyn_ltree[END_BLOCK].fc.Freq := 1;
s.static_len := Long(0);
s.opt_len := Long(0);
s.matches := 0;
s.last_lit := 0;
end;
const
SMALLEST = 1;
{ Index within the heap array of least frequent node in the Huffman tree }
{ ===========================================================================
Initialize the tree data structures for a new zlib stream. }
procedure _tr_init(var s : deflate_state);
begin
tr_static_init;
s.compressed_len := Long(0);
s.l_desc.dyn_tree := tree_ptr(@s.dyn_ltree);
s.l_desc.stat_desc := @static_l_desc;
s.d_desc.dyn_tree := tree_ptr(@s.dyn_dtree);
s.d_desc.stat_desc := @static_d_desc;
s.bl_desc.dyn_tree := tree_ptr(@s.bl_tree);
s.bl_desc.stat_desc := @static_bl_desc;
s.bi_buf := 0;
s.bi_valid := 0;
s.last_eob_len := 8; { enough lookahead for inflate }
{$ifdef DEBUG}
s.bits_sent := Long(0);
{$endif}
{ Initialize the first block of the first file: }
init_block(s);
end;
{ ===========================================================================
Remove the smallest element from the heap and recreate the heap with
one less element. Updates heap and heap_len.
macro pqremove(s, tree, top)
begin
top := s.heap[SMALLEST];
s.heap[SMALLEST] := s.heap[s.heap_len];
Dec(s.heap_len);
pqdownheap(s, tree, SMALLEST);
end
}
{ ===========================================================================
Compares to subtrees, using the tree depth as tie breaker when
the subtrees have equal frequency. This minimizes the worst case length.
macro smaller(tree, n, m, depth)
( (tree[n].Freq < tree[m].Freq) or
((tree[n].Freq = tree[m].Freq) and (depth[n] <= depth[m])) )
}
{ ===========================================================================
Restore the heap property by moving down the tree starting at node k,
exchanging a node with the smallest of its two sons if necessary, stopping
when the heap property is re-established (each father smaller than its
two sons). }
{local}
procedure pqdownheap(var s : deflate_state;
var tree : tree_type; { the tree to restore }
k : int); { node to move down }
var
v : int;
j : int;
begin
v := s.heap[k];
j := k shl 1; { left son of k }
while (j <= s.heap_len) do
begin
{ Set j to the smallest of the two sons: }
if (j < s.heap_len) and
{smaller(tree, s.heap[j+1], s.heap[j], s.depth)}
( (tree[s.heap[j+1]].fc.Freq < tree[s.heap[j]].fc.Freq) or
((tree[s.heap[j+1]].fc.Freq = tree[s.heap[j]].fc.Freq) and
(s.depth[s.heap[j+1]] <= s.depth[s.heap[j]])) ) then
begin
Inc(j);
end;
{ Exit if v is smaller than both sons }
if {(smaller(tree, v, s.heap[j], s.depth))}
( (tree[v].fc.Freq < tree[s.heap[j]].fc.Freq) or
((tree[v].fc.Freq = tree[s.heap[j]].fc.Freq) and
(s.depth[v] <= s.depth[s.heap[j]])) ) then
break;
{ Exchange v with the smallest son }
s.heap[k] := s.heap[j];
k := j;
{ And continue down the tree, setting j to the left son of k }
j := j shl 1;
end;
s.heap[k] := v;
end;
{ ===========================================================================
Compute the optimal bit lengths for a tree and update the total bit length
for the current block.
IN assertion: the fields freq and dad are set, heap[heap_max] and
above are the tree nodes sorted by increasing frequency.
OUT assertions: the field len is set to the optimal bit length, the
array bl_count contains the frequencies for each bit length.
The length opt_len is updated; static_len is also updated if stree is
not null. }
{local}
procedure gen_bitlen(var s : deflate_state;
var desc : tree_desc); { the tree descriptor }
var
tree : tree_ptr;
max_code : int;
stree : tree_ptr; {const}
extra : pzIntfArray; {const}
base : int;
max_length : int;
h : int; { heap index }
n, m : int; { iterate over the tree elements }
bits : int; { bit length }
xbits : int; { extra bits }
f : ush; { frequency }
overflow : int; { number of elements with bit length too large }
begin
tree := desc.dyn_tree;
max_code := desc.max_code;
stree := desc.stat_desc^.static_tree;
extra := desc.stat_desc^.extra_bits;
base := desc.stat_desc^.extra_base;
max_length := desc.stat_desc^.max_length;
overflow := 0;
for bits := 0 to MAX_BITS do
s.bl_count[bits] := 0;
{ In a first pass, compute the optimal bit lengths (which may
overflow in the case of the bit length tree). }
tree^[s.heap[s.heap_max]].dl.Len := 0; { root of the heap }
for h := s.heap_max+1 to HEAP_SIZE-1 do
begin
n := s.heap[h];
bits := tree^[tree^[n].dl.Dad].dl.Len + 1;
if (bits > max_length) then
begin
bits := max_length;
Inc(overflow);
end;
tree^[n].dl.Len := ush(bits);
{ We overwrite tree[n].dl.Dad which is no longer needed }
if (n > max_code) then
continue; { not a leaf node }
Inc(s.bl_count[bits]);
xbits := 0;
if (n >= base) then
xbits := extra^[n-base];
f := tree^[n].fc.Freq;
Inc(s.opt_len, ulg(f) * (bits + xbits));
if (stree <> NIL) then
Inc(s.static_len, ulg(f) * (stree^[n].dl.Len + xbits));
end;
if (overflow = 0) then
exit;
{$ifdef DEBUG}
Tracev(^M'bit length overflow');
{$endif}
{ This happens for example on obj2 and pic of the Calgary corpus }
{ Find the first bit length which could increase: }
repeat
bits := max_length-1;
while (s.bl_count[bits] = 0) do
Dec(bits);
Dec(s.bl_count[bits]); { move one leaf down the tree }
Inc(s.bl_count[bits+1], 2); { move one overflow item as its brother }
Dec(s.bl_count[max_length]);
{ The brother of the overflow item also moves one step up,
but this does not affect bl_count[max_length] }
Dec(overflow, 2);
until (overflow <= 0);
{ Now recompute all bit lengths, scanning in increasing frequency.
h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
lengths instead of fixing only the wrong ones. This idea is taken
from 'ar' written by Haruhiko Okumura.) }
h := HEAP_SIZE; { Delphi3: compiler warning w/o this }
for bits := max_length downto 1 do
begin
n := s.bl_count[bits];
while (n <> 0) do
begin
Dec(h);
m := s.heap[h];
if (m > max_code) then
continue;
if (tree^[m].dl.Len <> unsigned(bits)) then
begin
{$ifdef DEBUG}
Trace('code '+IntToStr(m)+' bits '+IntToStr(tree^[m].dl.Len)
+'.'+IntToStr(bits));
{$ENDIF}
Inc(s.opt_len, (long(bits) - long(tree^[m].dl.Len))
* long(tree^[m].fc.Freq) );
tree^[m].dl.Len := ush(bits);
end;
Dec(n);
end;
end;
end;
{ ===========================================================================
Construct one Huffman tree and assigns the code bit strings and lengths.
Update the total bit length for the current block.
IN assertion: the field freq is set for all tree elements.
OUT assertions: the fields len and code are set to the optimal bit length
and corresponding code. The length opt_len is updated; static_len is
also updated if stree is not null. The field max_code is set. }
{local}
procedure build_tree(var s : deflate_state;
var desc : tree_desc); { the tree descriptor }
var
tree : tree_ptr;
stree : tree_ptr; {const}
elems : int;
n, m : int; { iterate over heap elements }
max_code : int; { largest code with non zero frequency }
node : int; { new node being created }
begin
tree := desc.dyn_tree;
stree := desc.stat_desc^.static_tree;
elems := desc.stat_desc^.elems;
max_code := -1;
{ Construct the initial heap, with least frequent element in
heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
heap[0] is not used. }
s.heap_len := 0;
s.heap_max := HEAP_SIZE;
for n := 0 to elems-1 do
begin
if (tree^[n].fc.Freq <> 0) then
begin
max_code := n;
Inc(s.heap_len);
s.heap[s.heap_len] := n;
s.depth[n] := 0;
end
else
begin
tree^[n].dl.Len := 0;
end;
end;
{ The pkzip format requires that at least one distance code exists,
and that at least one bit should be sent even if there is only one
possible code. So to avoid special checks later on we force at least
two codes of non zero frequency. }
while (s.heap_len < 2) do
begin
Inc(s.heap_len);
if (max_code < 2) then
begin
Inc(max_code);
s.heap[s.heap_len] := max_code;
node := max_code;
end
else
begin
s.heap[s.heap_len] := 0;
node := 0;
end;
tree^[node].fc.Freq := 1;
s.depth[node] := 0;
Dec(s.opt_len);
if (stree <> NIL) then
Dec(s.static_len, stree^[node].dl.Len);
{ node is 0 or 1 so it does not have extra bits }
end;
desc.max_code := max_code;
{ The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
establish sub-heaps of increasing lengths: }
for n := s.heap_len div 2 downto 1 do
pqdownheap(s, tree^, n);
{ Construct the Huffman tree by repeatedly combining the least two
frequent nodes. }
node := elems; { next internal node of the tree }
repeat
{pqremove(s, tree, n);} { n := node of least frequency }
n := s.heap[SMALLEST];
s.heap[SMALLEST] := s.heap[s.heap_len];
Dec(s.heap_len);
pqdownheap(s, tree^, SMALLEST);
m := s.heap[SMALLEST]; { m := node of next least frequency }
Dec(s.heap_max);
s.heap[s.heap_max] := n; { keep the nodes sorted by frequency }
Dec(s.heap_max);
s.heap[s.heap_max] := m;
{ Create a new node father of n and m }
tree^[node].fc.Freq := tree^[n].fc.Freq + tree^[m].fc.Freq;
{ maximum }
if (s.depth[n] >= s.depth[m]) then
s.depth[node] := uch (s.depth[n] + 1)
else
s.depth[node] := uch (s.depth[m] + 1);
tree^[m].dl.Dad := ush(node);
tree^[n].dl.Dad := ush(node);
{$ifdef DUMP_BL_TREE}
if (tree = tree_ptr(@s.bl_tree)) then
begin
WriteLn(#13'node ',node,'(',tree^[node].fc.Freq,') sons ',n,
'(',tree^[n].fc.Freq,') ', m, '(',tree^[m].fc.Freq,')');
end;
{$endif}
{ and insert the new node in the heap }
s.heap[SMALLEST] := node;
Inc(node);
pqdownheap(s, tree^, SMALLEST);
until (s.heap_len < 2);
Dec(s.heap_max);
s.heap[s.heap_max] := s.heap[SMALLEST];
{ At this point, the fields freq and dad are set. We can now
generate the bit lengths. }
gen_bitlen(s, desc);
{ The field len is now set, we can generate the bit codes }
gen_codes (tree, max_code, s.bl_count);
end;
{ ===========================================================================
Scan a literal or distance tree to determine the frequencies of the codes
in the bit length tree. }
{local}
procedure scan_tree(var s : deflate_state;
var tree : array of ct_data; { the tree to be scanned }
max_code : int); { and its largest code of non zero frequency }
var
n : int; { iterates over all tree elements }
prevlen : int; { last emitted length }
curlen : int; { length of current code }
nextlen : int; { length of next code }
count : int; { repeat count of the current code }
max_count : int; { max repeat count }
min_count : int; { min repeat count }
begin
prevlen := -1;
nextlen := tree[0].dl.Len;
count := 0;
max_count := 7;
min_count := 4;
if (nextlen = 0) then
begin
max_count := 138;
min_count := 3;
end;
tree[max_code+1].dl.Len := ush($ffff); { guard }
for n := 0 to max_code do
begin
curlen := nextlen;
nextlen := tree[n+1].dl.Len;
Inc(count);
if (count < max_count) and (curlen = nextlen) then
continue
else
if (count < min_count) then
Inc(s.bl_tree[curlen].fc.Freq, count)
else
if (curlen <> 0) then
begin
if (curlen <> prevlen) then
Inc(s.bl_tree[curlen].fc.Freq);
Inc(s.bl_tree[REP_3_6].fc.Freq);
end
else
if (count <= 10) then
Inc(s.bl_tree[REPZ_3_10].fc.Freq)
else
Inc(s.bl_tree[REPZ_11_138].fc.Freq);
count := 0;
prevlen := curlen;
if (nextlen = 0) then
begin
max_count := 138;
min_count := 3;
end
else
if (curlen = nextlen) then
begin
max_count := 6;
min_count := 3;
end
else
begin
max_count := 7;
min_count := 4;
end;
end;
end;
{ ===========================================================================
Send a literal or distance tree in compressed form, using the codes in
bl_tree. }
{local}
procedure send_tree(var s : deflate_state;
var tree : array of ct_data; { the tree to be scanned }
max_code : int); { and its largest code of non zero frequency }
var
n : int; { iterates over all tree elements }
prevlen : int; { last emitted length }
curlen : int; { length of current code }
nextlen : int; { length of next code }
count : int; { repeat count of the current code }
max_count : int; { max repeat count }
min_count : int; { min repeat count }
begin
prevlen := -1;
nextlen := tree[0].dl.Len;
count := 0;
max_count := 7;
min_count := 4;
{ tree[max_code+1].dl.Len := -1; } { guard already set }
if (nextlen = 0) then
begin
max_count := 138;
min_count := 3;
end;
for n := 0 to max_code do
begin
curlen := nextlen;
nextlen := tree[n+1].dl.Len;
Inc(count);
if (count < max_count) and (curlen = nextlen) then
continue
else
if (count < min_count) then
begin
repeat
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(curlen));
{$ENDIF}
send_bits(s, s.bl_tree[curlen].fc.Code, s.bl_tree[curlen].dl.Len);
Dec(count);
until (count = 0);
end
else
if (curlen <> 0) then
begin
if (curlen <> prevlen) then
begin
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(curlen));
{$ENDIF}
send_bits(s, s.bl_tree[curlen].fc.Code, s.bl_tree[curlen].dl.Len);
Dec(count);
end;
{$IFDEF DEBUG}
Assert((count >= 3) and (count <= 6), ' 3_6?');
{$ENDIF}
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(REP_3_6));
{$ENDIF}
send_bits(s, s.bl_tree[REP_3_6].fc.Code, s.bl_tree[REP_3_6].dl.Len);
send_bits(s, count-3, 2);
end
else
if (count <= 10) then
begin
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(REPZ_3_10));
{$ENDIF}
send_bits(s, s.bl_tree[REPZ_3_10].fc.Code, s.bl_tree[REPZ_3_10].dl.Len);
send_bits(s, count-3, 3);
end
else
begin
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(REPZ_11_138));
{$ENDIF}
send_bits(s, s.bl_tree[REPZ_11_138].fc.Code, s.bl_tree[REPZ_11_138].dl.Len);
send_bits(s, count-11, 7);
end;
count := 0;
prevlen := curlen;
if (nextlen = 0) then
begin
max_count := 138;
min_count := 3;
end
else
if (curlen = nextlen) then
begin
max_count := 6;
min_count := 3;
end
else
begin
max_count := 7;
min_count := 4;
end;
end;
end;
{ ===========================================================================
Construct the Huffman tree for the bit lengths and return the index in
bl_order of the last bit length code to send. }
{local}
function build_bl_tree(var s : deflate_state) : int;
var
max_blindex : int; { index of last bit length code of non zero freq }
begin
{ Determine the bit length frequencies for literal and distance trees }
scan_tree(s, s.dyn_ltree, s.l_desc.max_code);
scan_tree(s, s.dyn_dtree, s.d_desc.max_code);
{ Build the bit length tree: }
build_tree(s, s.bl_desc);
{ opt_len now includes the length of the tree representations, except
the lengths of the bit lengths codes and the 5+5+4 bits for the counts. }
{ Determine the number of bit length codes to send. The pkzip format
requires that at least 4 bit length codes be sent. (appnote.txt says
3 but the actual value used is 4.) }
for max_blindex := BL_CODES-1 downto 3 do
begin
if (s.bl_tree[bl_order[max_blindex]].dl.Len <> 0) then
break;
end;
{ Update opt_len to include the bit length tree and counts }
Inc(s.opt_len, 3*(max_blindex+1) + 5+5+4);
{$ifdef DEBUG}
Tracev(^M'dyn trees: dyn %ld, stat %ld {s.opt_len, s.static_len}');
{$ENDIF}
build_bl_tree := max_blindex;
end;
{ ===========================================================================
Send the header for a block using dynamic Huffman trees: the counts, the
lengths of the bit length codes, the literal tree and the distance tree.
IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. }
{local}
procedure send_all_trees(var s : deflate_state;
lcodes : int;
dcodes : int;
blcodes : int); { number of codes for each tree }
var
rank : int; { index in bl_order }
begin
{$IFDEF DEBUG}
Assert ((lcodes >= 257) and (dcodes >= 1) and (blcodes >= 4),
'not enough codes');
Assert ((lcodes <= L_CODES) and (dcodes <= D_CODES)
and (blcodes <= BL_CODES), 'too many codes');
Tracev(^M'bl counts: ');
{$ENDIF}
send_bits(s, lcodes-257, 5); { not +255 as stated in appnote.txt }
send_bits(s, dcodes-1, 5);
send_bits(s, blcodes-4, 4); { not -3 as stated in appnote.txt }
for rank := 0 to blcodes-1 do
begin
{$ifdef DEBUG}
Tracev(^M'bl code '+IntToStr(bl_order[rank]));
{$ENDIF}
send_bits(s, s.bl_tree[bl_order[rank]].dl.Len, 3);
end;
{$ifdef DEBUG}
Tracev(^M'bl tree: sent '+IntToStr(s.bits_sent));
{$ENDIF}
send_tree(s, s.dyn_ltree, lcodes-1); { literal tree }
{$ifdef DEBUG}
Tracev(^M'lit tree: sent '+IntToStr(s.bits_sent));
{$ENDIF}
send_tree(s, s.dyn_dtree, dcodes-1); { distance tree }
{$ifdef DEBUG}
Tracev(^M'dist tree: sent '+IntToStr(s.bits_sent));
{$ENDIF}
end;
{ ===========================================================================
Flush the bit buffer and align the output on a byte boundary }
{local}
procedure bi_windup(var s : deflate_state);
begin
if (s.bi_valid > 8) then
begin
{put_short(s, s.bi_buf);}
s.pending_buf^[s.pending] := uch(s.bi_buf and $ff);
Inc(s.pending);
s.pending_buf^[s.pending] := uch(ush(s.bi_buf) shr 8);;
Inc(s.pending);
end
else
if (s.bi_valid > 0) then
begin
{put_byte(s, (Byte)s^.bi_buf);}
s.pending_buf^[s.pending] := Byte(s.bi_buf);
Inc(s.pending);
end;
s.bi_buf := 0;
s.bi_valid := 0;
{$ifdef DEBUG}
s.bits_sent := (s.bits_sent+7) and (not 7);
{$endif}
end;
{ ===========================================================================
Copy a stored block, storing first the length and its
one's complement if requested. }
{local}
procedure copy_block(var s : deflate_state;
buf : pcharf; { the input data }
len : unsigned; { its length }
header : boolean); { true if block header must be written }
begin
bi_windup(s); { align on byte boundary }
s.last_eob_len := 8; { enough lookahead for inflate }
if (header) then
begin
{put_short(s, (ush)len);}
s.pending_buf^[s.pending] := uch(ush(len) and $ff);
Inc(s.pending);
s.pending_buf^[s.pending] := uch(ush(len) shr 8);;
Inc(s.pending);
{put_short(s, (ush)~len);}
s.pending_buf^[s.pending] := uch(ush(not len) and $ff);
Inc(s.pending);
s.pending_buf^[s.pending] := uch(ush(not len) shr 8);;
Inc(s.pending);
{$ifdef DEBUG}
Inc(s.bits_sent, 2*16);
{$endif}
end;
{$ifdef DEBUG}
Inc(s.bits_sent, ulg(len shl 3));
{$endif}
while (len <> 0) do
begin
Dec(len);
{put_byte(s, *buf++);}
s.pending_buf^[s.pending] := buf^;
Inc(buf);
Inc(s.pending);
end;
end;
{ ===========================================================================
Send a stored block }
procedure _tr_stored_block(var s : deflate_state;
buf : pcharf; { input block }
stored_len : ulg; { length of input block }
eof : boolean); { true if this is the last block for a file }
begin
send_bits(s, (STORED_BLOCK shl 1)+ord(eof), 3); { send block type }
s.compressed_len := (s.compressed_len + 3 + 7) and ulg(not Long(7));
Inc(s.compressed_len, (stored_len + 4) shl 3);
copy_block(s, buf, unsigned(stored_len), TRUE); { with header }
end;
{ ===========================================================================
Flush the bit buffer, keeping at most 7 bits in it. }
{local}
procedure bi_flush(var s : deflate_state);
begin
if (s.bi_valid = 16) then
begin
{put_short(s, s.bi_buf);}
s.pending_buf^[s.pending] := uch(s.bi_buf and $ff);
Inc(s.pending);
s.pending_buf^[s.pending] := uch(ush(s.bi_buf) shr 8);;
Inc(s.pending);
s.bi_buf := 0;
s.bi_valid := 0;
end
else
if (s.bi_valid >= 8) then
begin
{put_byte(s, (Byte)s^.bi_buf);}
s.pending_buf^[s.pending] := Byte(s.bi_buf);
Inc(s.pending);
s.bi_buf := s.bi_buf shr 8;
Dec(s.bi_valid, 8);
end;
end;
{ ===========================================================================
Send one empty static block to give enough lookahead for inflate.
This takes 10 bits, of which 7 may remain in the bit buffer.
The current inflate code requires 9 bits of lookahead. If the
last two codes for the previous block (real code plus EOB) were coded
on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
the last real code. In this case we send two empty static blocks instead
of one. (There are no problems if the previous block is stored or fixed.)
To simplify the code, we assume the worst case of last real code encoded
on one bit only. }
procedure _tr_align(var s : deflate_state);
begin
send_bits(s, STATIC_TREES shl 1, 3);
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(END_BLOCK));
{$ENDIF}
send_bits(s, static_ltree[END_BLOCK].fc.Code, static_ltree[END_BLOCK].dl.Len);
Inc(s.compressed_len, Long(10)); { 3 for block type, 7 for EOB }
bi_flush(s);
{ Of the 10 bits for the empty block, we have already sent
(10 - bi_valid) bits. The lookahead for the last real code (before
the EOB of the previous block) was thus at least one plus the length
of the EOB plus what we have just sent of the empty static block. }
if (1 + s.last_eob_len + 10 - s.bi_valid < 9) then
begin
send_bits(s, STATIC_TREES shl 1, 3);
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(END_BLOCK));
{$ENDIF}
send_bits(s, static_ltree[END_BLOCK].fc.Code, static_ltree[END_BLOCK].dl.Len);
Inc(s.compressed_len, Long(10));
bi_flush(s);
end;
s.last_eob_len := 7;
end;
{ ===========================================================================
Set the data type to ASCII or BINARY, using a crude approximation:
binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
IN assertion: the fields freq of dyn_ltree are set and the total of all
frequencies does not exceed 64K (to fit in an int on 16 bit machines). }
{local}
procedure set_data_type(var s : deflate_state);
var
n : int;
ascii_freq : unsigned;
bin_freq : unsigned;
begin
n := 0;
ascii_freq := 0;
bin_freq := 0;
while (n < 7) do
begin
Inc(bin_freq, s.dyn_ltree[n].fc.Freq);
Inc(n);
end;
while (n < 128) do
begin
Inc(ascii_freq, s.dyn_ltree[n].fc.Freq);
Inc(n);
end;
while (n < LITERALS) do
begin
Inc(bin_freq, s.dyn_ltree[n].fc.Freq);
Inc(n);
end;
if (bin_freq > (ascii_freq shr 2)) then
s.data_type := Byte(Z_BINARY)
else
s.data_type := Byte(Z_ASCII);
end;
{ ===========================================================================
Send the block data compressed using the given Huffman trees }
{local}
procedure compress_block(var s : deflate_state;
var ltree : array of ct_data; { literal tree }
var dtree : array of ct_data); { distance tree }
var
dist : unsigned; { distance of matched string }
lc : int; { match length or unmatched char (if dist == 0) }
lx : unsigned; { running index in l_buf }
code : unsigned; { the code to send }
extra : int; { number of extra bits to send }
begin
lx := 0;
if (s.last_lit <> 0) then
repeat
dist := s.d_buf^[lx];
lc := s.l_buf^[lx];
Inc(lx);
if (dist = 0) then
begin
{ send a literal byte }
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(lc));
Tracecv((lc > 31) and (lc < 128), ' '+char(lc)+' ');
{$ENDIF}
send_bits(s, ltree[lc].fc.Code, ltree[lc].dl.Len);
end
else
begin
{ Here, lc is the match length - MIN_MATCH }
code := _length_code[lc];
{ send the length code }
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(code+LITERALS+1));
{$ENDIF}
send_bits(s, ltree[code+LITERALS+1].fc.Code, ltree[code+LITERALS+1].dl.Len);
extra := extra_lbits[code];
if (extra <> 0) then
begin
Dec(lc, base_length[code]);
send_bits(s, lc, extra); { send the extra length bits }
end;
Dec(dist); { dist is now the match distance - 1 }
{code := d_code(dist);}
if (dist < 256) then
code := _dist_code[dist]
else
code := _dist_code[256+(dist shr 7)];
{$IFDEF DEBUG}
Assert (code < D_CODES, 'bad d_code');
{$ENDIF}
{ send the distance code }
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(code));
{$ENDIF}
send_bits(s, dtree[code].fc.Code, dtree[code].dl.Len);
extra := extra_dbits[code];
if (extra <> 0) then
begin
Dec(dist, base_dist[code]);
send_bits(s, dist, extra); { send the extra distance bits }
end;
end; { literal or match pair ? }
{ Check that the overlay between pending_buf and d_buf+l_buf is ok: }
{$IFDEF DEBUG}
Assert(s.pending < s.lit_bufsize + 2*lx, 'pendingBuf overflow');
{$ENDIF}
until (lx >= s.last_lit);
{$ifdef DEBUG}
Tracevvv(#13'cd '+IntToStr(END_BLOCK));
{$ENDIF}
send_bits(s, ltree[END_BLOCK].fc.Code, ltree[END_BLOCK].dl.Len);
s.last_eob_len := ltree[END_BLOCK].dl.Len;
end;
{ ===========================================================================
Determine the best encoding for the current block: dynamic trees, static
trees or store, and output the encoded block to the zip file. This function
returns the total compressed length for the file so far. }
function _tr_flush_block (var s : deflate_state;
buf : pcharf; { input block, or NULL if too old }
stored_len : ulg; { length of input block }
eof : boolean) : ulg; { true if this is the last block for a file }
var
opt_lenb, static_lenb : ulg; { opt_len and static_len in bytes }
max_blindex : int; { index of last bit length code of non zero freq }
vstatic_ltree : tstatic_ltree;
vstatic_dtree : tstatic_dtree;
begin
max_blindex := 0;
{ Build the Huffman trees unless a stored block is forced }
if (s.level > 0) then
begin
{ Check if the file is ascii or binary }
if (s.data_type = Z_UNKNOWN) then
set_data_type(s);
{ Construct the literal and distance trees }
build_tree(s, s.l_desc);
{$ifdef DEBUG}
Tracev(^M'lit data: dyn %ld, stat %ld {s.opt_len, s.static_len}');
{$ENDIF}
build_tree(s, s.d_desc);
{$ifdef DEBUG}
Tracev(^M'dist data: dyn %ld, stat %ld {s.opt_len, s.static_len}');
{$ENDIF}
{ At this point, opt_len and static_len are the total bit lengths of
the compressed block data, excluding the tree representations. }
{ Build the bit length tree for the above two trees, and get the index
in bl_order of the last bit length code to send. }
max_blindex := build_bl_tree(s);
{ Determine the best encoding. Compute first the block length in bytes}
opt_lenb := (s.opt_len+3+7) shr 3;
static_lenb := (s.static_len+3+7) shr 3;
{$ifdef DEBUG}
Tracev(^M'opt %lu(%lu) stat %lu(%lu) stored %lu lit %u '+
'{opt_lenb, s.opt_len, static_lenb, s.static_len, stored_len,'+
's.last_lit}');
{$ENDIF}
if (static_lenb <= opt_lenb) then
opt_lenb := static_lenb;
end
else
begin
{$IFDEF DEBUG}
Assert(buf <> pcharf(NIL), 'lost buf');
{$ENDIF}
static_lenb := stored_len + 5;
opt_lenb := static_lenb; { force a stored block }
end;
{ If compression failed and this is the first and last block,
and if the .zip file can be seeked (to rewrite the local header),
the whole file is transformed into a stored file: }
{$ifdef STORED_FILE_OK}
{$ifdef FORCE_STORED_FILE}
if eof and (s.compressed_len = Long(0)) then
begin { force stored file }
{$else}
if (stored_len <= opt_lenb) and eof and (s.compressed_len=Long(0))
and seekable()) do
begin
{$endif}
{ Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: }
if (buf = pcharf(0)) then
error ('block vanished');
copy_block(buf, unsigned(stored_len), 0); { without header }
s.compressed_len := stored_len shl 3;
s.method := STORED;
end
else
{$endif} { STORED_FILE_OK }
{$ifdef FORCE_STORED}
if (buf <> pchar(0)) then
begin { force stored block }
{$else}
if (stored_len+4 <= opt_lenb) and (buf <> pcharf(0)) then
begin
{ 4: two words for the lengths }
{$endif}
{ The test buf <> NULL is only necessary if LIT_BUFSIZE > WSIZE.
Otherwise we can't have processed more than WSIZE input bytes since
the last block flush, because compression would have been
successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
transform a block into a stored block. }
_tr_stored_block(s, buf, stored_len, eof);
{$ifdef FORCE_STATIC}
end
else
if (static_lenb >= 0) then
begin { force static trees }
{$else}
end
else
if (static_lenb = opt_lenb) then
begin
{$endif}
send_bits(s, (STATIC_TREES shl 1)+ord(eof), 3);
vstatic_ltree := static_ltree;
vstatic_dtree := static_dtree;
compress_block(s, vstatic_ltree, vstatic_dtree);
Inc(s.compressed_len, 3 + s.static_len);
end
else
begin
send_bits(s, (DYN_TREES shl 1)+ord(eof), 3);
send_all_trees(s, s.l_desc.max_code+1, s.d_desc.max_code+1,
max_blindex+1);
compress_block(s, s.dyn_ltree, s.dyn_dtree);
Inc(s.compressed_len, 3 + s.opt_len);
end;
{$ifdef DEBUG}
Assert (s.compressed_len = s.bits_sent, 'bad compressed size');
{$ENDIF}
init_block(s);
if (eof) then
begin
bi_windup(s);
Inc(s.compressed_len, 7); { align on byte boundary }
end;
{$ifdef DEBUG}
Tracev(#13'comprlen %lu(%lu) {s.compressed_len shr 3,'+
's.compressed_len-7*ord(eof)}');
{$ENDIF}
_tr_flush_block := s.compressed_len shr 3;
end;
{ ===========================================================================
Save the match info and tally the frequency counts. Return true if
the current block must be flushed. }
function _tr_tally (var s : deflate_state;
dist : unsigned; { distance of matched string }
lc : unsigned) : boolean; { match length-MIN_MATCH or unmatched char (if dist=0) }
var
{$IFDEF DEBUG}
MAX_DIST : ush;
{$ENDIF}
code : ush;
{$ifdef TRUNCATE_BLOCK}
var
out_length : ulg;
in_length : ulg;
dcode : int;
{$endif}
begin
s.d_buf^[s.last_lit] := ush(dist);
s.l_buf^[s.last_lit] := uch(lc);
Inc(s.last_lit);
if (dist = 0) then
begin
{ lc is the unmatched char }
Inc(s.dyn_ltree[lc].fc.Freq);
end
else
begin
Inc(s.matches);
{ Here, lc is the match length - MIN_MATCH }
Dec(dist); { dist := match distance - 1 }
{macro d_code(dist)}
if (dist) < 256 then
code := _dist_code[dist]
else
code := _dist_code[256+(dist shr 7)];
{$IFDEF DEBUG}
{macro MAX_DIST(s) <=> ((s)^.w_size-MIN_LOOKAHEAD)
In order to simplify the code, particularly on 16 bit machines, match
distances are limited to MAX_DIST instead of WSIZE. }
MAX_DIST := ush(s.w_size-MIN_LOOKAHEAD);
Assert((dist < ush(MAX_DIST)) and
(ush(lc) <= ush(MAX_MATCH-MIN_MATCH)) and
(ush(code) < ush(D_CODES)), '_tr_tally: bad match');
{$ENDIF}
Inc(s.dyn_ltree[_length_code[lc]+LITERALS+1].fc.Freq);
{s.dyn_dtree[d_code(dist)].Freq++;}
Inc(s.dyn_dtree[code].fc.Freq);
end;
{$ifdef TRUNCATE_BLOCK}
{ Try to guess if it is profitable to stop the current block here }
if (s.last_lit and $1fff = 0) and (s.level > 2) then
begin
{ Compute an upper bound for the compressed length }
out_length := ulg(s.last_lit)*Long(8);
in_length := ulg(long(s.strstart) - s.block_start);
for dcode := 0 to D_CODES-1 do
begin
Inc(out_length, ulg(s.dyn_dtree[dcode].fc.Freq *
(Long(5)+extra_dbits[dcode])) );
end;
out_length := out_length shr 3;
if (s.matches < s.last_lit div 2) and (out_length < in_length div 2) then
begin
_tr_tally := TRUE;
exit;
end;
end;
{$endif}
_tr_tally := (s.last_lit = s.lit_bufsize-1);
{ We avoid equality with lit_bufsize because of wraparound at 64K
on 16 bit machines and because stored blocks are restricted to
64K-1 bytes. }
end;
end.