forked from KolibriOS/kolibrios
2096 lines
55 KiB
NASM
2096 lines
55 KiB
NASM
; trees.asm -- output deflated data using Huffman coding
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; Copyright (C) 1995-2012 Jean-loup Gailly
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; detect_data_type() function provided freely by Cosmin Truta, 2006
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; For conditions of distribution and use, see copyright notice in zlib.h
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; ALGORITHM
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; The "deflation" process uses several Huffman trees. The more
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; common source values are represented by shorter bit sequences.
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; Each code tree is stored in a compressed form which is itself
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; a Huffman encoding of the lengths of all the code strings (in
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; ascending order by source values). The actual code strings are
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; reconstructed from the lengths in the inflate process, as described
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; in the deflate specification.
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; REFERENCES
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; Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
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; Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
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; Storer, James A.
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; Data Compression: Methods and Theory, pp. 49-50.
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; Computer Science Press, 1988. ISBN 0-7167-8156-5.
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; Sedgewick, R.
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; Algorithms, p290.
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; Addison-Wesley, 1983. ISBN 0-201-06672-6.
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; ===========================================================================
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; Constants
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MAX_BL_BITS equ 7
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; Bit length codes must not exceed MAX_BL_BITS bits
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END_BLOCK equ 256
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; end of block literal code
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REP_3_6 equ 16
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; repeat previous bit length 3-6 times (2 bits of repeat count)
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REPZ_3_10 equ 17
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; repeat a zero length 3-10 times (3 bits of repeat count)
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REPZ_11_138 equ 18
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; repeat a zero length 11-138 times (7 bits of repeat count)
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align 4
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extra_lbits dd \ ;int [LENGTH_CODES] ;extra bits for each length code
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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
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align 4
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extra_dbits dd \ ;int [D_CODES] ;extra bits for each distance code
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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
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align 4
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extra_blbits dd \ ;int [BL_CODES] ;extra bits for each bit length code
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7
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align 4
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bl_order db 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15
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; The lengths of the bit length codes are sent in order of decreasing
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; probability, to avoid transmitting the lengths for unused bit length codes.
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; ===========================================================================
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; Local data. These are initialized only once.
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DIST_CODE_LEN equ 512 ;see definition of array dist_code below
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if GEN_TREES_H eq 1 ;| !(STDC)
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; non ANSI compilers may not accept trees.inc
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align 4
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static_ltree rb sizeof.ct_data * (L_CODES+2)
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; The static literal tree. Since the bit lengths are imposed, there is no
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; need for the L_CODES extra codes used during heap construction. However
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; The codes 286 and 287 are needed to build a canonical tree (see _tr_init
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; below).
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align 4
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static_dtree rb sizeof.ct_data * D_CODES
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; The static distance tree. (Actually a trivial tree since all codes use
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; 5 bits.)
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align 4
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_dist_code rb DIST_CODE_LEN ;uch[]
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; Distance codes. The first 256 values correspond to the distances
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; 3 .. 258, the last 256 values correspond to the top 8 bits of
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; the 15 bit distances.
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align 4
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_length_code rb MAX_MATCH-MIN_MATCH+1 ;uch[]
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; length code for each normalized match length (0 == MIN_MATCH)
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align 4
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base_length rd LENGTH_CODES ;int[]
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; First normalized length for each code (0 = MIN_MATCH)
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align 4
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base_dist rd D_CODES ;int[]
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; First normalized distance for each code (0 = distance of 1)
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else
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include 'trees.inc'
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end if ;GEN_TREES_H
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struct static_tree_desc ;_s
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static_tree dd ? ;const ct_data * ;static tree or NULL
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extra_bits dd ? ;const intf * ;extra bits for each code or NULL
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extra_base dd ? ;int ;base index for extra_bits
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elems dd ? ;int ;max number of elements in the tree
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max_length dd ? ;int ;max bit length for the codes
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ends
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align 4
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static_l_desc static_tree_desc static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS
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align 4
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static_d_desc static_tree_desc static_dtree, extra_dbits, 0, D_CODES, MAX_BITS
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align 4
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static_bl_desc static_tree_desc 0, extra_blbits, 0, BL_CODES, MAX_BL_BITS
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; ===========================================================================
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; Local (static) routines in this file.
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macro send_code s, c, tree
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{
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if DEBUG eq 1
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; if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c))
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end if
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push eax ebx
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if c eq eax
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else
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mov eax,c
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end if
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imul eax,sizeof.ct_data
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add eax,tree
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movzx ebx,word[eax+Len]
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push ebx
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movzx ebx,word[eax+Code]
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push ebx
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stdcall send_bits, s ;tree[c].Code, tree[c].Len
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pop ebx eax
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}
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; Send a code of the given tree[c] and tree must not have side effects
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; ===========================================================================
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; Output a short LSB first on the stream.
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; IN assertion: there is enough room in pendingBuf.
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macro put_short s, w
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{
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movzx eax,word[s+deflate_state.pending]
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add eax,[s+deflate_state.pending_buf]
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mov word[eax],w
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add word[s+deflate_state.pending],2
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}
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; ===========================================================================
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; Send a value on a given number of bits.
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; IN assertion: length <= 16 and value fits in length bits.
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;void (s, value, length)
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; deflate_state* s
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; int value ;value to send
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; int length ;number of bits
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align 4
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proc send_bits uses eax ecx edi, s:dword, value:dword, length:dword
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; Tracevv((stderr," l %2d v %4x ", length, value));
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zlib_debug 'send_bits value = %d',[value]
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;if DEBUG eq 1
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mov eax,[length]
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cmp eax,0
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jle @f
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cmp eax,15
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jle .end1
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@@:
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zlib_assert 'invalid length' ;Assert(..>0 && ..<=15)
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.end1:
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mov edi,[s]
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add [edi+deflate_state.bits_sent],eax
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; If not enough room in bi_buf, use (valid) bits from bi_buf and
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; (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
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; unused bits in value.
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mov ecx,Buf_size
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sub ecx,eax
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cmp [edi+deflate_state.bi_valid],ecx
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jle @f ;if (..>..)
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mov eax,[value]
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mov ecx,[edi+deflate_state.bi_valid]
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shl eax,cl
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or [edi+deflate_state.bi_buf],ax
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mov cx,[edi+deflate_state.bi_buf]
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put_short edi, cx
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mov eax,[value]
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mov ecx,Buf_size
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sub ecx,[edi+deflate_state.bi_valid]
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shr eax,cl
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mov [edi+deflate_state.bi_buf],ax
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mov eax,[length]
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sub eax,Buf_size
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jmp .end0
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@@: ;else
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mov eax,[value]
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mov ecx,[edi+deflate_state.bi_valid]
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shl eax,cl
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or [edi+deflate_state.bi_buf],ax
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mov eax,[length]
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.end0:
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add [edi+deflate_state.bi_valid],eax
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;else ;!DEBUG
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;{ int len = length;
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; if (s->bi_valid > (int)Buf_size - len) {
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; int val = value;
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; s->bi_buf |= (uint_16)val << s->bi_valid;
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; put_short(s, s->bi_buf);
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; s->bi_buf = (uint_16)val >> (Buf_size - s->bi_valid);
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; s->bi_valid += len - Buf_size;
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; } else {
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; s->bi_buf |= (uint_16)(value) << s->bi_valid;
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; s->bi_valid += len;
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; }
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;}
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;end if ;DEBUG
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ret
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endp
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; the arguments must not have side effects
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; ===========================================================================
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; Initialize the various 'constant' tables.
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;int static_init_done = 0
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;void ()
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align 4
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proc tr_static_init
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if GEN_TREES_H eq 1
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; int n ;iterates over tree elements
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; int bits ;bit counter
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; int length ;length value
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; int code ;code value
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; int dist ;distance index
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; uint_16 bl_count[MAX_BITS+1];
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; number of codes at each bit length for an optimal tree
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; if (static_init_done) return;
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; For some embedded targets, global variables are not initialized:
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;if NO_INIT_GLOBAL_POINTERS
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; static_l_desc.static_tree = static_ltree;
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; static_l_desc.extra_bits = extra_lbits;
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; static_d_desc.static_tree = static_dtree;
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; static_d_desc.extra_bits = extra_dbits;
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; static_bl_desc.extra_bits = extra_blbits;
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;end if
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; Initialize the mapping length (0..255) -> length code (0..28)
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; length = 0;
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; for (code = 0; code < LENGTH_CODES-1; code++) {
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; base_length[code] = length;
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; for (n = 0; n < (1<<extra_lbits[code]); n++) {
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; _length_code[length++] = (uch)code;
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; }
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; }
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; Assert (length == 256, "tr_static_init: length != 256");
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; Note that the length 255 (match length 258) can be represented
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; in two different ways: code 284 + 5 bits or code 285, so we
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; overwrite length_code[255] to use the best encoding:
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; _length_code[length-1] = (uch)code;
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; Initialize the mapping dist (0..32K) -> dist code (0..29)
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; dist = 0;
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; for (code = 0 ; code < 16; code++) {
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; base_dist[code] = dist;
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; for (n = 0; n < (1<<extra_dbits[code]); n++) {
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; _dist_code[dist++] = (uch)code;
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; }
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; }
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; Assert (dist == 256, "tr_static_init: dist != 256");
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; dist >>= 7; /* from now on, all distances are divided by 128 */
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; for ( ; code < D_CODES; code++) {
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; base_dist[code] = dist << 7;
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; for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
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; _dist_code[256 + dist++] = (uch)code;
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; }
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; }
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; Assert (dist == 256, "tr_static_init: 256+dist != 512");
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; Construct the codes of the static literal tree
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; for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
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; n = 0;
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; while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
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; while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
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; while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
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; while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
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; Codes 286 and 287 do not exist, but we must include them in the
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; tree construction to get a canonical Huffman tree (longest code
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; all ones)
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; gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
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; The static distance tree is trivial:
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; for (n = 0; n < D_CODES; n++) {
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; static_dtree[n].Len = 5;
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; static_dtree[n].Code = bi_reverse((unsigned)n, 5);
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; }
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; static_init_done = 1;
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if GEN_TREES_H eq 1
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call gen_trees_header
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end if
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end if ;(GEN_TREES_H) | !(STDC)
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ret
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endp
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; ===========================================================================
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; Genererate the file trees.h describing the static trees.
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;# define SEPARATOR(i, last, width) \
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; ((i) == (last)? "\n};\n\n" : \
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; ((i) % (width) == (width)-1 ? ",\n" : ", "))
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;void ()
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align 4
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proc gen_trees_header
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; FILE *header = fopen("trees.inc", "w");
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; int i;
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; Assert (header != NULL, "Can't open trees.inc");
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; fprintf(header,
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; "/* header created automatically with -DGEN_TREES_H */\n\n");
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; fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
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; for (i = 0; i < L_CODES+2; i++) {
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; fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
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; static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
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; }
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; fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
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; for (i = 0; i < D_CODES; i++) {
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; fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
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; static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
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; }
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; fprintf(header, "const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {\n");
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; for (i = 0; i < DIST_CODE_LEN; i++) {
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; fprintf(header, "%2u%s", _dist_code[i],
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; SEPARATOR(i, DIST_CODE_LEN-1, 20));
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; }
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; fprintf(header,
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; "const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
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; for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
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; fprintf(header, "%2u%s", _length_code[i],
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; SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
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; }
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; fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
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; for (i = 0; i < LENGTH_CODES; i++) {
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; fprintf(header, "%1u%s", base_length[i],
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; SEPARATOR(i, LENGTH_CODES-1, 20));
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; }
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; fprintf(header, "local const int base_dist[D_CODES] = {\n");
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; for (i = 0; i < D_CODES; i++) {
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; fprintf(header, "%5u%s", base_dist[i],
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; SEPARATOR(i, D_CODES-1, 10));
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; }
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; fclose(header);
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ret
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endp
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; ===========================================================================
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; Initialize the tree data structures for a new zlib stream.
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;void (s)
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; deflate_state* s;
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align 4
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proc _tr_init uses eax edi, s:dword
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mov edi,[s]
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zlib_debug '_tr_init'
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call tr_static_init
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mov eax,edi
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add eax,deflate_state.dyn_ltree
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mov [edi+deflate_state.l_desc.dyn_tree],eax
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mov [edi+deflate_state.l_desc.stat_desc],static_l_desc
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add eax,deflate_state.dyn_dtree-deflate_state.dyn_ltree
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mov [edi+deflate_state.d_desc.dyn_tree],eax
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mov [edi+deflate_state.d_desc.stat_desc],static_d_desc
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add eax,deflate_state.bl_tree-deflate_state.dyn_dtree
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mov [edi+deflate_state.bl_desc.dyn_tree],eax
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mov [edi+deflate_state.bl_desc.stat_desc],static_bl_desc;
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mov word[edi+deflate_state.bi_buf],0
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mov dword[edi+deflate_state.bi_valid],0
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if DEBUG eq 1
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mov dword[edi+deflate_state.compressed_len],0
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mov dword[edi+deflate_state.bits_sent],0
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end if
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; Initialize the first block of the first file:
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stdcall init_block,edi
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ret
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endp
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; ===========================================================================
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; Initialize a new block.
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;void (s)
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; deflate_state* s
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align 4
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proc init_block uses eax ecx edi, s:dword
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; int n ;iterates over tree elements
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mov edi,[s]
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; Initialize the trees.
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mov eax,edi
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add eax,deflate_state.dyn_ltree+Freq
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mov ecx,L_CODES
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@@:
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mov word[eax],0
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add eax,sizeof.ct_data
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loop @b
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mov eax,edi
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add eax,deflate_state.dyn_dtree+Freq
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mov ecx,D_CODES
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@@:
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mov word[eax],0
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add eax,sizeof.ct_data
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loop @b
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mov eax,edi
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add eax,deflate_state.bl_tree+Freq
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mov ecx,BL_CODES
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@@:
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mov word[eax],0
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add eax,sizeof.ct_data
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loop @b
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mov ecx,sizeof.ct_data*END_BLOCK+deflate_state.dyn_ltree+Freq
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mov word[ecx+edi],1
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mov dword[edi+deflate_state.static_len],0
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mov dword[edi+deflate_state.opt_len],0
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mov dword[edi+deflate_state.matches],0
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mov dword[edi+deflate_state.last_lit],0
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ret
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endp
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SMALLEST equ 1
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; Index within the heap array of least frequent node in the Huffman tree
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|
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; ===========================================================================
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; Remove the smallest element from the heap and recreate the heap with
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; one less element. Updates heap and heap_len.
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macro pqremove s, tree, top
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{
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mov eax,s
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add eax,deflate_state.heap+2*SMALLEST
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movzx top,word[eax]
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push ebx
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mov ebx,[s+deflate_state.heap_len]
|
|
mov bx,[s+deflate_state.heap+2*ebx]
|
|
mov word[eax],bx
|
|
dec dword[s+deflate_state.heap_len]
|
|
pop ebx
|
|
stdcall pqdownheap, s, tree, SMALLEST
|
|
}
|
|
|
|
; ===========================================================================
|
|
; 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, m_end
|
|
{
|
|
;if (..<.. || (..==.. && depth[n] <= depth[m]))
|
|
local .end0
|
|
movzx eax,n
|
|
imul eax,sizeof.ct_data
|
|
add eax,tree
|
|
mov ax,word[eax+Freq]
|
|
movzx ebx,m
|
|
imul ebx,sizeof.ct_data
|
|
add ebx,tree
|
|
mov bx,word[ebx+Freq]
|
|
cmp ax,bx
|
|
jl .end0
|
|
jne m_end
|
|
movzx eax,n
|
|
add eax,depth
|
|
mov al,byte[eax]
|
|
movzx ebx,m
|
|
add ebx,depth
|
|
mov bl,byte[ebx]
|
|
cmp al,bl
|
|
jg m_end
|
|
.end0:
|
|
}
|
|
|
|
; ===========================================================================
|
|
; 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).
|
|
|
|
;void (s, tree, k)
|
|
; deflate_state* s
|
|
; ct_data* tree ;the tree to restore
|
|
; int k ;node to move down
|
|
align 4
|
|
proc pqdownheap, s:dword, tree:dword, k:dword
|
|
locals
|
|
v dw ?
|
|
endl
|
|
pushad
|
|
mov edi,[s]
|
|
mov eax,[k]
|
|
zlib_debug 'pqdownheap k = %d',eax
|
|
mov esi,eax
|
|
shl esi,1
|
|
mov ax,[edi+deflate_state.heap+2*eax]
|
|
mov [v],ax
|
|
;esi = j ;left son of k
|
|
.cycle0: ;while (..<=..)
|
|
cmp esi,[edi+deflate_state.heap_len]
|
|
jg .cycle0end
|
|
; Set j to the smallest of the two sons:
|
|
;;cmp esi,[edi+deflate_state.heap_len]
|
|
jge .end1 ;if (..<.. &&
|
|
mov ecx,edi
|
|
add ecx,deflate_state.depth
|
|
mov edx,esi
|
|
shl edx,1
|
|
add edx,edi
|
|
add edx,deflate_state.heap
|
|
smaller [tree], word[edx+2], word[edx], ecx, .end1
|
|
inc esi
|
|
.end1:
|
|
; Exit if v is smaller than both sons
|
|
mov ecx,edi
|
|
add ecx,deflate_state.depth
|
|
mov dx,[edi+deflate_state.heap+2*esi]
|
|
smaller [tree], [v], dx, ecx, .end2
|
|
jmp .cycle0end ;break
|
|
.end2:
|
|
; Exchange v with the smallest son
|
|
mov dx,[edi+deflate_state.heap+2*esi]
|
|
mov eax,[k]
|
|
mov [edi+deflate_state.heap+2*eax],dx
|
|
mov [k],esi
|
|
; And continue down the tree, setting j to the left son of k
|
|
shl esi,1
|
|
jmp .cycle0
|
|
.cycle0end:
|
|
mov eax,[k]
|
|
mov bx,[v]
|
|
mov [edi+deflate_state.heap+2*eax],bx
|
|
popad
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; 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.
|
|
|
|
;void (s, desc)
|
|
; deflate_state* s
|
|
; tree_desc* desc ;the tree descriptor
|
|
align 4
|
|
proc gen_bitlen, s:dword, desc:dword
|
|
locals
|
|
tree dd ? ;ct_data* ;= desc.dyn_tree
|
|
max_code dd ? ;int ;= desc.max_code
|
|
stree dd ? ;ct_data* ;= desc.stat_desc.static_tree
|
|
extra dd ? ;intf* ;= desc.stat_desc.extra_bits
|
|
base dd ? ;int ;= desc.stat_desc.extra_base
|
|
max_length dd ? ;int ;= desc.stat_desc.max_length
|
|
h dd ? ;int ;heap index
|
|
m dd ? ;int ;iterate over the tree elements
|
|
bits dd ? ;int ;bit length
|
|
xbits dd ? ;int ;extra bits
|
|
f dw ? ;uint_16 ;frequency
|
|
overflow dd 0 ;int ;number of elements with bit length too large
|
|
endl
|
|
pushad
|
|
zlib_debug 'gen_bitlen'
|
|
mov edi,[s]
|
|
mov edx,[desc]
|
|
mov eax,[edx+tree_desc.dyn_tree]
|
|
mov [tree],eax
|
|
mov eax,[edx+tree_desc.max_code]
|
|
mov [max_code],eax
|
|
mov ebx,[edx+tree_desc.stat_desc]
|
|
mov eax,[ebx+static_tree_desc.static_tree]
|
|
mov [stree],eax
|
|
mov eax,[ebx+static_tree_desc.extra_bits]
|
|
mov [extra],eax
|
|
mov eax,[ebx+static_tree_desc.extra_base]
|
|
mov [base],eax
|
|
mov eax,[ebx+static_tree_desc.max_length]
|
|
mov [max_length],eax
|
|
|
|
xor ecx,ecx
|
|
.cycle0:
|
|
cmp ecx,MAX_BITS
|
|
jg .cycle0end ;for (..;..<=..;..)
|
|
mov word[edi+deflate_state.bl_count+2*ecx],0
|
|
inc ecx
|
|
jmp .cycle0
|
|
align 4
|
|
.cycle0end:
|
|
|
|
; In a first pass, compute the optimal bit lengths (which may
|
|
; overflow in the case of the bit length tree).
|
|
|
|
mov eax,[edi+deflate_state.heap_max]
|
|
movzx eax,word[edi+deflate_state.heap+2*eax]
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
mov word[eax+Len],0 ;root of the heap
|
|
|
|
mov eax,[edi+deflate_state.heap_max]
|
|
inc eax
|
|
mov [h],eax
|
|
.cycle1:
|
|
cmp dword[h],HEAP_SIZE
|
|
jge .cycle1end ;for (..;..<..;..)
|
|
mov eax,[h]
|
|
movzx ecx,word[edi+deflate_state.heap+2*eax]
|
|
;ecx = n
|
|
mov eax,sizeof.ct_data
|
|
imul eax,ecx
|
|
add eax,[tree]
|
|
movzx eax,word[eax+Dad]
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
movzx eax,word[eax+Len]
|
|
inc eax
|
|
mov [bits],eax ;bits = tree[tree[n].Dad].Len + 1
|
|
mov eax,[max_length]
|
|
cmp [bits],eax
|
|
jle @f ;if (..>..)
|
|
mov [bits],eax
|
|
inc dword[overflow]
|
|
@@:
|
|
mov esi,[bits]
|
|
mov eax,sizeof.ct_data
|
|
imul eax,ecx
|
|
add eax,[tree]
|
|
mov word[eax+Len],si
|
|
; We overwrite tree[n].Dad which is no longer needed
|
|
|
|
cmp ecx,[max_code]
|
|
jle @f
|
|
inc dword[h]
|
|
jmp .cycle1 ;if (..>..) continue ;not a leaf node
|
|
@@:
|
|
|
|
mov eax,[bits]
|
|
shl eax,1 ;*= sizeof.uint_16
|
|
inc word[eax+edi+deflate_state.bl_count]
|
|
mov dword[xbits],0
|
|
cmp ecx,[base]
|
|
jl @f ;if (..>=..)
|
|
mov eax,ecx
|
|
sub eax,[base]
|
|
shl eax,2 ;*= sizeof.dd
|
|
add eax,[extra]
|
|
mov eax,[eax]
|
|
mov [xbits],eax
|
|
@@:
|
|
mov eax,sizeof.ct_data
|
|
imul eax,ecx
|
|
add eax,[tree]
|
|
movzx eax,word[eax+Freq]
|
|
mov [f],ax
|
|
mov esi,[bits]
|
|
add esi,[xbits]
|
|
imul eax,esi
|
|
add [edi+deflate_state.opt_len],eax
|
|
cmp dword[stree],0
|
|
je @f ;if (..)
|
|
movzx eax,word[f]
|
|
mov esi,sizeof.ct_data
|
|
imul esi,ecx
|
|
add esi,[tree]
|
|
movzx esi,word[esi+Len]
|
|
add esi,[xbits]
|
|
imul eax,esi
|
|
add [edi+deflate_state.static_len],eax
|
|
@@:
|
|
inc dword[h]
|
|
jmp .cycle1
|
|
align 4
|
|
.cycle1end:
|
|
cmp dword[overflow],0
|
|
je .end_f ;if (..==0) return
|
|
|
|
; Trace((stderr,"\nbit length overflow\n"));
|
|
; This happens for example on obj2 and pic of the Calgary corpus
|
|
|
|
; Find the first bit length which could increase:
|
|
.cycle2: ;do
|
|
mov eax,[max_length]
|
|
dec eax
|
|
mov [bits],eax
|
|
shl eax,1 ;*= sizeof.dw
|
|
add eax,edi
|
|
add eax,deflate_state.bl_count
|
|
@@:
|
|
cmp word[eax],0
|
|
jne @f ;while (..==0) bits--
|
|
dec dword[bits]
|
|
sub eax,2
|
|
jmp @b
|
|
@@:
|
|
dec word[eax] ;move one leaf down the tree
|
|
add word[eax+2],2 ;move one overflow item as its brother
|
|
mov eax,[max_length]
|
|
dec word[edi+deflate_state.bl_count+2*eax]
|
|
; The brother of the overflow item also moves one step up,
|
|
; but this does not affect bl_count[max_length]
|
|
|
|
sub dword[overflow],2
|
|
cmp dword[overflow],0
|
|
jg .cycle2 ;while (..>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.)
|
|
|
|
mov eax,[max_length]
|
|
mov [bits],eax
|
|
.cycle3:
|
|
cmp dword[bits],0
|
|
je .end_f ;for (..;..!=0;..)
|
|
mov eax,[bits]
|
|
shl eax,1 ;*= sizeof.dw
|
|
movzx ecx,word[eax+edi+deflate_state.bl_count]
|
|
.cycle4: ;while (..!=0)
|
|
cmp ecx,0
|
|
je .cycle4end
|
|
dec dword[h]
|
|
mov eax,[h]
|
|
movzx eax,word[edi+deflate_state.heap+2*eax]
|
|
mov [m],eax ;m = s.heap[--h]
|
|
cmp eax,[max_code]
|
|
jle @f ;if (..>..) continue
|
|
dec ecx
|
|
jmp .cycle4
|
|
@@:
|
|
mov esi,[m]
|
|
imul esi,sizeof.ct_data
|
|
add esi,[tree] ;esi = &tree[m]
|
|
mov eax,[bits]
|
|
cmp word[esi+Len],ax
|
|
je @f ;if (..!=..)
|
|
; Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
|
|
movzx ebx,word[esi+Len]
|
|
sub eax,ebx
|
|
movzx ebx,word[esi+Freq]
|
|
imul eax,ebx ;eax = (bits - tree[m].Len) * tree[m].Freq
|
|
add [edi+deflate_state.opt_len],eax
|
|
mov eax,[bits]
|
|
mov word[esi+Len],ax
|
|
@@:
|
|
dec ecx
|
|
jmp .cycle4
|
|
.cycle4end:
|
|
dec dword[bits]
|
|
jmp .cycle3
|
|
.end_f:
|
|
popad
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; 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.
|
|
|
|
;void (tree, max_code, bl_count)
|
|
; ct_data *tree ;the tree to decorate
|
|
; int max_code ;largest code with non zero frequency
|
|
; uint_16p bl_count ;number of codes at each bit length
|
|
align 4
|
|
proc gen_codes uses eax ebx ecx edx edi, tree:dword, max_code:dword, bl_count:dword
|
|
locals
|
|
u_code dw 0 ;uint_16 ;running code value
|
|
bits dd 1 ;int ;bit index
|
|
next_code rw MAX_BITS+1 ;uint_16[] ;next code value for each bit length
|
|
endl
|
|
; The distribution counts are first used to generate the code values
|
|
; without bit reversal.
|
|
zlib_debug 'gen_codes'
|
|
mov ebx,ebp
|
|
sub ebx,2*(MAX_BITS+1)
|
|
|
|
.cycle0: ;for (..;..<=..;..)
|
|
cmp dword[bits],MAX_BITS
|
|
jg .cycle0end
|
|
mov eax,[bits]
|
|
dec eax
|
|
shl eax,1
|
|
add eax,[bl_count]
|
|
mov ax,word[eax]
|
|
add ax,[u_code]
|
|
shl ax,1 ;ax = (u_code + bl_count[bits-1]) << 1
|
|
mov [u_code],ax
|
|
mov ecx,[bits]
|
|
mov word[ebx+2*ecx],ax ;next_code[bits] = u_code
|
|
inc dword[bits]
|
|
jmp .cycle0
|
|
.cycle0end:
|
|
; Check that the bit counts in bl_count are consistent. The last code
|
|
; must be all ones.
|
|
|
|
mov eax,[bl_count]
|
|
mov ax,word[eax+2*MAX_BITS]
|
|
add ax,[u_code]
|
|
dec ax
|
|
cmp ax,(1 shl MAX_BITS)-1
|
|
je @f
|
|
zlib_assert 'inconsistent bit counts' ;Assert(..==..)
|
|
@@:
|
|
; Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
|
|
|
|
xor ecx,ecx ;n = 0
|
|
.cycle1: ;for (..;..<=..;..)
|
|
cmp ecx,[max_code]
|
|
jg .cycle1end
|
|
mov edx,sizeof.ct_data
|
|
imul edx,ecx
|
|
add edx,[tree] ;edx = &tree[n]
|
|
movzx edi,word[edx+Len]
|
|
cmp edi,0
|
|
jne @f ;if (..==0) continue
|
|
inc ecx
|
|
jmp .cycle1
|
|
@@:
|
|
; Now reverse the bits
|
|
movzx eax,word[ebx+2*edi]
|
|
stdcall bi_reverse, eax, edi
|
|
mov word[edx+Code],ax
|
|
inc word[ebx+2*edi]
|
|
|
|
; Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
|
|
; n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
|
|
inc ecx
|
|
jmp .cycle1
|
|
.cycle1end:
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; 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.
|
|
|
|
;void (s, desc)
|
|
; deflate_state* s
|
|
; tree_desc *desc ;the tree descriptor
|
|
align 4
|
|
proc build_tree uses eax ebx ecx edx edi, s:dword, desc:dword
|
|
locals
|
|
tree dd ? ;ct_data* ;= desc.dyn_tree
|
|
stree dd ? ;ct_data* ;= desc.stat_desc.static_tree
|
|
elems dd ? ;int ;= desc.stat_desc.elems
|
|
m dd ? ;int ;iterate over heap elements
|
|
max_code dd -1 ;int ;largest code with non zero frequency
|
|
node dd ? ;int ;new node being created
|
|
endl
|
|
; 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.
|
|
mov ebx,[desc]
|
|
mov eax,[ebx+tree_desc.dyn_tree]
|
|
mov [tree],eax
|
|
mov ecx,[ebx+tree_desc.stat_desc]
|
|
mov eax,[ecx+static_tree_desc.static_tree]
|
|
mov [stree],eax
|
|
mov ecx,[ecx+static_tree_desc.elems]
|
|
mov [elems],ecx
|
|
mov edi,[s]
|
|
zlib_debug 'build_tree cycle0 ecx = %d',ecx
|
|
|
|
mov dword[edi+deflate_state.heap_len],0
|
|
mov dword[edi+deflate_state.heap_max],HEAP_SIZE
|
|
|
|
cmp ecx,0
|
|
jle .cycle0end
|
|
xor edx,edx
|
|
.cycle0: ;for (..;..<..;..)
|
|
mov eax,edx
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
cmp word[eax+Freq],0
|
|
je @f ;if (..!=0)
|
|
inc dword[edi+deflate_state.heap_len]
|
|
mov eax,[edi+deflate_state.heap_len]
|
|
mov [max_code],edx
|
|
mov [edi+deflate_state.heap+2*eax],dx
|
|
mov eax,edx
|
|
add eax,edi
|
|
add eax,deflate_state.depth
|
|
mov byte[eax],0
|
|
jmp .end0
|
|
align 4
|
|
@@: ;else
|
|
mov word[eax+Len],0
|
|
.end0:
|
|
inc edx
|
|
loop .cycle0
|
|
align 4
|
|
.cycle0end:
|
|
|
|
; 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.
|
|
|
|
.cycle1: ;while (..<..)
|
|
cmp dword[edi+deflate_state.heap_len],2
|
|
jge .cycle1end
|
|
inc dword[edi+deflate_state.heap_len]
|
|
xor eax,eax
|
|
cmp dword[max_code],2
|
|
jge @f
|
|
inc dword[max_code]
|
|
mov eax,[max_code]
|
|
@@:
|
|
mov ecx,[edi+deflate_state.heap_len]
|
|
mov [edi+deflate_state.heap+2*ecx],ax
|
|
mov [node],eax
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
mov word[eax+Freq],1
|
|
mov eax,[node]
|
|
mov byte[edi+deflate_state.depth+eax],0
|
|
dec dword[edi+deflate_state.opt_len]
|
|
cmp dword[stree],0
|
|
je .cycle1 ;if (..)
|
|
mov eax,[node]
|
|
imul eax,sizeof.ct_data
|
|
add eax,[stree]
|
|
movzx eax,word[eax+Len]
|
|
sub [edi+deflate_state.static_len],eax
|
|
; node is 0 or 1 so it does not have extra bits
|
|
jmp .cycle1
|
|
align 4
|
|
.cycle1end:
|
|
mov eax,[max_code]
|
|
mov [ebx+tree_desc.max_code],eax
|
|
|
|
; The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
|
|
; establish sub-heaps of increasing lengths:
|
|
|
|
mov ecx,[edi+deflate_state.heap_len]
|
|
shr ecx,1
|
|
.cycle2: ;for (..;..>=..;..)
|
|
cmp ecx,1
|
|
jl .cycle2end
|
|
stdcall pqdownheap, edi, [tree], ecx
|
|
dec ecx
|
|
jmp .cycle2
|
|
align 4
|
|
.cycle2end:
|
|
|
|
; Construct the Huffman tree by repeatedly combining the least two
|
|
; frequent nodes.
|
|
|
|
mov eax,[elems]
|
|
mov [node],eax ;next internal node of the tree
|
|
.cycle3: ;do
|
|
pqremove edi, [tree], ecx ;n = node of least frequency
|
|
movzx edx,word[eax]
|
|
mov [m],edx ;m = node of next least frequency
|
|
|
|
mov eax,[edi+deflate_state.heap_max]
|
|
dec eax
|
|
mov [edi+deflate_state.heap+2*eax],cx ;keep the nodes sorted by frequency
|
|
dec eax
|
|
mov [edi+deflate_state.heap_max],eax
|
|
mov [edi+deflate_state.heap+2*eax],dx
|
|
|
|
; Create a new node father of n and m
|
|
;;mov edx,[m]
|
|
imul edx,sizeof.ct_data
|
|
add edx,[tree]
|
|
mov ax,word[edx+Freq]
|
|
mov edx,ecx
|
|
imul edx,sizeof.ct_data
|
|
add edx,[tree]
|
|
add ax,word[edx+Freq]
|
|
mov edx,[node]
|
|
imul edx,sizeof.ct_data
|
|
add edx,[tree]
|
|
mov word[edx+Freq],ax
|
|
|
|
mov eax,ecx
|
|
add eax,edi
|
|
add eax,deflate_state.depth
|
|
mov al,byte[eax]
|
|
mov edx,[m]
|
|
add edx,edi
|
|
add edx,deflate_state.depth
|
|
mov ah,byte[edx]
|
|
cmp al,ah
|
|
jl @f ;if (al>=ah) al=al : al=ah
|
|
mov al,ah
|
|
@@:
|
|
inc al
|
|
mov edx,[node]
|
|
add edx,edi
|
|
add edx,deflate_state.depth
|
|
mov byte[edx],al
|
|
|
|
mov eax,[node]
|
|
mov edx,[m]
|
|
imul edx,sizeof.ct_data
|
|
add edx,[tree]
|
|
mov [edx+Dad],ax
|
|
mov edx,ecx
|
|
imul edx,sizeof.ct_data
|
|
add edx,[tree]
|
|
mov [edx+Dad],ax
|
|
;if DUMP_BL_TREE eq 1
|
|
; if (tree == s->bl_tree) {
|
|
; fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
|
|
; node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
|
|
; }
|
|
;end if
|
|
; and insert the new node in the heap
|
|
mov ecx,[node]
|
|
mov [edi+deflate_state.heap+2*SMALLEST],cx
|
|
inc dword[node]
|
|
stdcall pqdownheap, edi, [tree], SMALLEST
|
|
cmp dword[edi+deflate_state.heap_len],2
|
|
jge .cycle3 ;while (..>=..)
|
|
|
|
mov cx,[edi+deflate_state.heap+2*SMALLEST]
|
|
dec dword[edi+deflate_state.heap_max]
|
|
mov eax,[edi+deflate_state.heap_max]
|
|
mov [edi+deflate_state.heap+2*eax],cx
|
|
|
|
; At this point, the fields freq and dad are set. We can now
|
|
; generate the bit lengths.
|
|
|
|
stdcall gen_bitlen, edi, [desc]
|
|
|
|
; The field len is now set, we can generate the bit codes
|
|
mov eax,edi
|
|
add eax,deflate_state.bl_count
|
|
stdcall gen_codes, [tree], [max_code], eax
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Scan a literal or distance tree to determine the frequencies of the codes
|
|
; in the bit length tree.
|
|
|
|
;void (s, tree, max_code)
|
|
; deflate_state* s
|
|
; ct_data *tree ;the tree to be scanned
|
|
; int max_code ;and its largest code of non zero frequency
|
|
align 4
|
|
proc scan_tree uses eax ebx ecx edi, s:dword, tree:dword, max_code:dword
|
|
locals
|
|
n dd ? ;int ;iterates over all tree elements
|
|
prevlen dd -1 ;int ;last emitted length
|
|
curlen dd ? ;int ;length of current code
|
|
nextlen dd ? ;int ;= tree[0].Len ;length of next code
|
|
count dd 0 ;int ;repeat count of the current code
|
|
max_count dd 7 ;int ;max repeat count
|
|
min_count dd 4 ;int ;min repeat count
|
|
endl
|
|
mov edi,[s]
|
|
zlib_debug 'scan_tree'
|
|
mov eax,[tree]
|
|
movzx eax,word[eax+Len]
|
|
mov [nextlen],eax
|
|
cmp eax,0
|
|
jne @f ;if (..==0)
|
|
mov dword[max_count],138
|
|
mov dword[min_count],3
|
|
@@:
|
|
mov eax,[max_code]
|
|
inc eax
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
mov word[eax+Len],0xffff ;guard
|
|
|
|
xor ecx,ecx
|
|
.cycle0:
|
|
cmp ecx,[max_code]
|
|
jg .cycle0end ;for (..;..<=..;..)
|
|
mov eax,[nextlen]
|
|
mov [curlen],eax
|
|
mov eax,ecx
|
|
inc eax
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
movzx eax,word[eax+Len]
|
|
mov [nextlen],eax
|
|
inc dword[count]
|
|
mov ebx,[count]
|
|
cmp ebx,[max_count]
|
|
jge .end0
|
|
mov eax,[nextlen]
|
|
cmp [curlen],eax
|
|
jne .end0 ;if (..<.. && ..==..)
|
|
inc ecx
|
|
jmp .cycle0 ;continue
|
|
.end0:
|
|
cmp ebx,[min_count]
|
|
jge .end1 ;else if (..<..)
|
|
mov eax,[curlen]
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Freq
|
|
add word[eax],bx
|
|
jmp .end4
|
|
.end1:
|
|
cmp dword[curlen],0
|
|
je .end2 ;else if (..!=0)
|
|
mov eax,[curlen]
|
|
cmp eax,[prevlen]
|
|
je @f ;if (..!=..)
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Freq
|
|
inc word[eax]
|
|
@@:
|
|
mov eax,REP_3_6
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Freq
|
|
inc word[eax]
|
|
jmp .end4
|
|
.end2:
|
|
cmp ebx,10
|
|
jg .end3 ;else if (..<=..)
|
|
mov eax,REPZ_3_10
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Freq
|
|
inc word[eax]
|
|
jmp .end4
|
|
.end3: ;else
|
|
mov eax,REPZ_11_138
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Freq
|
|
inc word[eax]
|
|
.end4:
|
|
mov dword[curlen],0
|
|
mov eax,[curlen]
|
|
mov [prevlen],eax
|
|
mov [nextlen],eax
|
|
cmp eax,0
|
|
jne .end5 ;if (..==0)
|
|
mov dword[max_count],138
|
|
mov dword[min_count],3
|
|
jmp .end7
|
|
.end5:
|
|
mov eax,[curlen]
|
|
cmp eax,[nextlen]
|
|
jne .end6 ;else if (..==..)
|
|
mov dword[max_count],6
|
|
mov dword[min_count],3
|
|
jmp .end7
|
|
.end6: ;else
|
|
mov dword[max_count],7
|
|
mov dword[min_count],4
|
|
.end7:
|
|
inc ecx
|
|
jmp .cycle0
|
|
.cycle0end:
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Send a literal or distance tree in compressed form, using the codes in
|
|
; bl_tree.
|
|
|
|
;void (s, tree, max_code)
|
|
; deflate_state* s
|
|
; ct_data *tree ;the tree to be scanned
|
|
; int max_code ;and its largest code of non zero frequency
|
|
align 4
|
|
proc send_tree uses eax ebx ecx edi, s:dword, tree:dword, max_code:dword
|
|
locals
|
|
n dd ? ;int ;iterates over all tree elements
|
|
prevlen dd -1 ;int ;last emitted length
|
|
curlen dd ? ;int ;length of current code
|
|
nextlen dd ? ;int ;= tree[0].Len ;length of next code
|
|
count dd 0 ;int ;repeat count of the current code
|
|
max_count dd 7 ;int ;max repeat count
|
|
min_count dd 4 ;int ;min repeat count
|
|
endl
|
|
mov edi,[s]
|
|
zlib_debug 'send_tree'
|
|
; *** tree[max_code+1].Len = -1 ;guard already set
|
|
mov eax,[tree]
|
|
movzx eax,word[eax+Len]
|
|
mov [nextlen],eax
|
|
cmp eax,0
|
|
jne @f ;if (..==0)
|
|
mov dword[max_count],138
|
|
mov dword[min_count],3
|
|
@@:
|
|
|
|
xor ecx,ecx
|
|
.cycle0: ;for (..;..<=..;..)
|
|
cmp ecx,[max_code]
|
|
jg .cycle0end
|
|
mov eax,[nextlen]
|
|
mov [curlen],eax
|
|
mov eax,ecx
|
|
inc eax
|
|
imul eax,sizeof.ct_data
|
|
add eax,[tree]
|
|
movzx eax,word[eax+Len]
|
|
mov [nextlen],eax
|
|
inc dword[count]
|
|
mov ebx,[count]
|
|
cmp ebx,[max_count]
|
|
jge .end0
|
|
mov eax,[nextlen]
|
|
cmp [curlen],eax
|
|
jne .end0 ;if (..<.. && ..==..)
|
|
inc ecx
|
|
jmp .cycle0 ;continue
|
|
.end0:
|
|
cmp ebx,[min_count]
|
|
jge .end1 ;else if (..<..)
|
|
@@: ;do
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree
|
|
send_code edi, [curlen], ebx
|
|
dec dword[count]
|
|
cmp dword[count],0
|
|
jne @b ;while (..!=0)
|
|
jmp .end4
|
|
align 4
|
|
.end1:
|
|
cmp dword[curlen],0
|
|
je .end2 ;else if (..!=0)
|
|
mov eax,[curlen]
|
|
cmp eax,[prevlen]
|
|
je @f ;if (..!=..)
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree
|
|
send_code edi, eax, ebx
|
|
dec dword[count]
|
|
@@:
|
|
cmp dword[count],3
|
|
jl @f
|
|
cmp dword[count],6
|
|
jle .end8
|
|
@@:
|
|
zlib_assert ' 3_6?' ;Assert(..>=.. && ..<=..)
|
|
.end8:
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree
|
|
send_code edi, REP_3_6, ebx
|
|
mov ebx,[count]
|
|
sub ebx,3
|
|
stdcall send_bits, edi, ebx, 2
|
|
jmp .end4
|
|
.end2:
|
|
cmp ebx,10
|
|
jg .end3 ;else if (..<=..)
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree
|
|
send_code edi, REPZ_3_10, ebx
|
|
mov ebx,[count]
|
|
sub ebx,3
|
|
stdcall send_bits, edi, ebx, 3
|
|
jmp .end4
|
|
.end3: ;else
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree
|
|
send_code edi, REPZ_11_138, ebx
|
|
mov ebx,[count]
|
|
sub ebx,11
|
|
stdcall send_bits, edi, ebx, 7
|
|
.end4:
|
|
mov dword[curlen],0
|
|
mov eax,[curlen]
|
|
mov [prevlen],eax
|
|
mov [nextlen],eax
|
|
cmp eax,0
|
|
jne .end5 ;if (..==0)
|
|
mov dword[max_count],138
|
|
mov dword[min_count],3
|
|
jmp .end7
|
|
.end5:
|
|
mov eax,[curlen]
|
|
cmp eax,[nextlen]
|
|
jne .end6 ;else if (..==..)
|
|
mov dword[max_count],6
|
|
mov dword[min_count],3
|
|
jmp .end7
|
|
.end6: ;else
|
|
mov dword[max_count],7
|
|
mov dword[min_count],4
|
|
.end7:
|
|
inc ecx
|
|
jmp .cycle0
|
|
align 4
|
|
.cycle0end:
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Construct the Huffman tree for the bit lengths and return the index in
|
|
; bl_order of the last bit length code to send.
|
|
|
|
;int (s)
|
|
; deflate_state* s
|
|
align 4
|
|
proc build_bl_tree uses edi, s:dword
|
|
locals
|
|
max_blindex dd ? ;int ;index of last bit length code of non zero freq
|
|
endl
|
|
mov edi,[s]
|
|
; Determine the bit length frequencies for literal and distance trees
|
|
mov eax,edi
|
|
add eax,deflate_state.dyn_ltree
|
|
stdcall scan_tree, edi, eax, [edi+deflate_state.l_desc.max_code]
|
|
mov eax,edi
|
|
add eax,deflate_state.dyn_dtree
|
|
stdcall scan_tree, edi, eax, [edi+deflate_state.d_desc.max_code]
|
|
|
|
; Build the bit length tree:
|
|
mov eax,edi
|
|
add eax,deflate_state.bl_desc
|
|
stdcall build_tree, edi, eax
|
|
; 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.)
|
|
|
|
mov dword[max_blindex],BL_CODES-1
|
|
.cycle0: ;for (..;..>=..;..)
|
|
cmp dword[max_blindex],3
|
|
jl .cycle0end
|
|
dec dword[max_blindex]
|
|
mov eax,[max_blindex]
|
|
add eax,bl_order
|
|
movzx eax,byte[eax]
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.bl_tree+Len
|
|
cmp word[eax],0
|
|
jne .cycle0end ;if (..!=0) break
|
|
jmp .cycle0
|
|
.cycle0end:
|
|
; Update opt_len to include the bit length tree and counts
|
|
mov eax,[max_blindex]
|
|
inc eax
|
|
imul eax,3
|
|
add eax,5+5+4
|
|
add [edi+deflate_state.opt_len],eax
|
|
; Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", s->opt_len, s->static_len));
|
|
|
|
mov eax,[max_blindex]
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; 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.
|
|
|
|
;void (s, lcodes, dcodes, blcodes)
|
|
; deflate_state* s
|
|
; int lcodes, dcodes, blcodes ;number of codes for each tree
|
|
align 4
|
|
proc send_all_trees uses eax ebx ecx edi, s:dword, lcodes:dword, dcodes:dword, blcodes:dword
|
|
;ecx = index in bl_order
|
|
zlib_debug 'send_all_trees'
|
|
cmp dword[lcodes],257
|
|
jl @f
|
|
cmp dword[dcodes],1
|
|
jl @f
|
|
cmp dword[blcodes],4
|
|
jge .end0
|
|
@@:
|
|
zlib_assert 'not enough codes' ;Assert(..>=.. && ..>=.. && ..>=..)
|
|
.end0:
|
|
cmp dword[lcodes],L_CODES
|
|
jg @f
|
|
cmp dword[dcodes],D_CODES
|
|
jg @f
|
|
cmp dword[blcodes],BL_CODES
|
|
jle .end1
|
|
@@:
|
|
zlib_assert 'too many codes' ;Assert(..<=.. && ..<=.. && ..<=..)
|
|
.end1:
|
|
; Tracev((stderr, "\nbl counts: "));
|
|
mov edi,[s]
|
|
mov eax,[lcodes]
|
|
sub eax,257
|
|
stdcall send_bits, edi, eax, 5 ;not +255 as stated in appnote.txt
|
|
mov eax,[dcodes]
|
|
dec eax
|
|
stdcall send_bits, edi, eax, 5
|
|
mov eax,[blcodes]
|
|
sub eax,4
|
|
stdcall send_bits, edi, eax, 4 ;not -3 as stated in appnote.txt
|
|
xor ecx,ecx
|
|
.cycle0:
|
|
cmp ecx,[blcodes]
|
|
jge .cycle0end ;for (..;..<..;..)
|
|
; Tracev((stderr, "\nbl code %2d ", bl_order[ecx]));
|
|
mov eax,ecx
|
|
add eax,bl_order
|
|
movzx eax,byte[eax]
|
|
imul eax,sizeof.ct_data
|
|
mov ebx,edi
|
|
add ebx,deflate_state.bl_tree+Len
|
|
add ebx,eax
|
|
stdcall send_bits, edi, ebx, 3
|
|
inc ecx
|
|
jmp .cycle0
|
|
align 4
|
|
.cycle0end:
|
|
; Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
|
|
|
|
mov ebx,[lcodes]
|
|
dec ebx
|
|
mov eax,edi
|
|
add eax,deflate_state.dyn_ltree
|
|
stdcall send_tree, edi, eax, ebx ;literal tree
|
|
; Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
|
|
|
|
mov ebx,[dcodes]
|
|
dec ebx
|
|
add eax,deflate_state.dyn_dtree-deflate_state.dyn_ltree
|
|
stdcall send_tree, edi, eax, ebx ;distance tree
|
|
; Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Send a stored block
|
|
|
|
;void (s, buf, stored_len, last)
|
|
; deflate_state* s
|
|
; charf *buf ;input block
|
|
; ulg stored_len ;length of input block
|
|
; int last ;one if this is the last block for a file
|
|
align 4
|
|
proc _tr_stored_block uses eax edi, s:dword, buf:dword, stored_len:dword, last:dword
|
|
mov edi,[s]
|
|
mov eax,[last]
|
|
add eax,STORED_BLOCK shl 1
|
|
stdcall send_bits, edi, eax, 3 ;send block type
|
|
if DEBUG eq 1
|
|
mov eax,[edi+deflate_state.compressed_len]
|
|
add eax,3+7
|
|
and eax,not 7
|
|
mov [edi+deflate_state.compressed_len],eax
|
|
mov eax,[stored_len]
|
|
add eax,4
|
|
shl eax,3
|
|
add [edi+deflate_state.compressed_len],eax
|
|
end if
|
|
stdcall copy_block, edi, [buf], [stored_len], 1 ;with header
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Flush the bits in the bit buffer to pending output (leaves at most 7 bits)
|
|
|
|
;void (s)
|
|
; deflate_state* s;
|
|
align 4
|
|
proc _tr_flush_bits, s:dword
|
|
stdcall bi_flush, [s]
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Send one empty static block to give enough lookahead for inflate.
|
|
; This takes 10 bits, of which 7 may remain in the bit buffer.
|
|
|
|
;void (s)
|
|
; deflate_state* s
|
|
align 4
|
|
proc _tr_align uses edi, s:dword
|
|
mov edi,[s]
|
|
stdcall send_bits, edi, STATIC_TREES shl 1, 3
|
|
send_code edi, END_BLOCK, static_ltree
|
|
if DEBUG eq 1
|
|
add [edi+deflate_state.compressed_len],10 ;3 for block type, 7 for EOB
|
|
end if
|
|
stdcall bi_flush, edi
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Determine the best encoding for the current block: dynamic trees, static
|
|
; trees or store, and output the encoded block to the zip file.
|
|
|
|
;void (s, buf, stored_len, last)
|
|
; deflate_state* s
|
|
; charf *buf ;input block, or NULL if too old
|
|
; ulg stored_len ;length of input block
|
|
; int last ;one if this is the last block for a file
|
|
align 4
|
|
proc _tr_flush_block uses eax ebx edi, s:dword, buf:dword, stored_len:dword, last:dword
|
|
locals
|
|
opt_lenb dd ? ;ulg
|
|
static_lenb dd ? ;opt_len and static_len in bytes
|
|
max_blindex dd 0 ;int ;index of last bit length code of non zero freq
|
|
endl
|
|
; Build the Huffman trees unless a stored block is forced
|
|
mov edi,[s]
|
|
zlib_debug '_tr_flush_block'
|
|
cmp word[edi+deflate_state.level],0
|
|
jle .end0 ;if (..>0)
|
|
|
|
; Check if the file is binary or text
|
|
mov ebx,[edi+deflate_state.strm]
|
|
cmp word[ebx+z_stream.data_type],Z_UNKNOWN
|
|
jne @f ;if (..==..)
|
|
stdcall detect_data_type, edi
|
|
mov [ebx+z_stream.data_type],ax
|
|
@@:
|
|
|
|
; Construct the literal and distance trees
|
|
mov eax,edi
|
|
add eax,deflate_state.l_desc
|
|
stdcall build_tree, edi, eax
|
|
; Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, s->static_len));
|
|
|
|
mov eax,edi
|
|
add eax,deflate_state.d_desc
|
|
stdcall build_tree, edi, eax
|
|
; Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, s->static_len));
|
|
; 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.
|
|
|
|
stdcall build_bl_tree, edi
|
|
mov [max_blindex],eax
|
|
|
|
; Determine the best encoding. Compute the block lengths in bytes.
|
|
mov eax,[edi+deflate_state.opt_len]
|
|
add eax,3+7
|
|
shr eax,3
|
|
mov [opt_lenb],eax
|
|
mov eax,[edi+deflate_state.static_len]
|
|
add eax,3+7
|
|
shr eax,3
|
|
mov [static_lenb],eax
|
|
|
|
; Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
|
|
; opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
|
|
; s->last_lit));
|
|
|
|
cmp eax,[opt_lenb]
|
|
jg .end1 ;if (..<=..)
|
|
mov [opt_lenb],eax
|
|
jmp .end1
|
|
.end0: ;else
|
|
cmp dword[buf],0
|
|
jne @f
|
|
zlib_assert 'lost buf' ;Assert(..!=0)
|
|
@@:
|
|
mov eax,[stored_len]
|
|
add eax,5
|
|
mov [static_lenb],eax
|
|
mov [opt_lenb],eax ;force a stored block
|
|
.end1:
|
|
|
|
if FORCE_STORED eq 1
|
|
cmp dword[buf],0
|
|
je .end2 ;if (..!=0) ;force stored block
|
|
else
|
|
mov eax,[stored_len]
|
|
add eax,4
|
|
cmp eax,[opt_lenb]
|
|
jg .end2
|
|
cmp dword[buf],0
|
|
je .end2 ;if (..<=.. && ..!=0)
|
|
;4: two words for the lengths
|
|
end if
|
|
; 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.
|
|
|
|
stdcall _tr_stored_block, edi, [buf], [stored_len], [last]
|
|
jmp .end4
|
|
.end2:
|
|
if FORCE_STATIC eq 1
|
|
cmp dword[static_lenb],0
|
|
jl .end3 ;else if (..>=0) ;force static trees
|
|
else
|
|
cmp word[edi+deflate_state.strategy],Z_FIXED
|
|
je @f
|
|
mov eax,[opt_lenb]
|
|
cmp [static_lenb],eax
|
|
je @f ;else if (..==.. || ..==..)
|
|
jmp .end3
|
|
@@:
|
|
end if
|
|
mov eax,STATIC_TREES shl 1
|
|
add eax,[last]
|
|
stdcall send_bits, edi, eax, 3
|
|
stdcall compress_block, edi, static_ltree, static_dtree
|
|
if DEBUG eq 1
|
|
mov eax,[edi+deflate_state.static_len]
|
|
add eax,3
|
|
add [edi+deflate_state.compressed_len],eax
|
|
end if
|
|
jmp .end4
|
|
.end3: ;else
|
|
mov eax,DYN_TREES shl 1
|
|
add eax,[last]
|
|
stdcall send_bits, edi, eax, 3
|
|
mov eax,[max_blindex]
|
|
inc eax
|
|
push eax
|
|
mov eax,[edi+deflate_state.d_desc.max_code]
|
|
inc eax
|
|
push eax
|
|
mov eax,[edi+deflate_state.l_desc.max_code]
|
|
inc eax
|
|
stdcall send_all_trees, edi, eax ;, ..., ...
|
|
mov eax,edi
|
|
add eax,deflate_state.dyn_dtree
|
|
push eax
|
|
add eax,deflate_state.dyn_ltree-deflate_state.dyn_dtree
|
|
stdcall compress_block, edi, eax ;, ...
|
|
if DEBUG eq 1
|
|
mov eax,[edi+deflate_state.opt_len]
|
|
add eax,3
|
|
add [edi+deflate_state.compressed_len],eax
|
|
end if
|
|
.end4:
|
|
; Assert (s->compressed_len == s->bits_sent, "bad compressed size");
|
|
; The above check is made mod 2^32, for files larger than 512 MB
|
|
; and uLong implemented on 32 bits.
|
|
|
|
stdcall init_block,edi
|
|
|
|
cmp dword[last],0
|
|
je @f ;if (..)
|
|
stdcall bi_windup,edi
|
|
if DEBUG eq 1
|
|
add [edi+deflate_state.compressed_len],7 ;align on byte boundary
|
|
end if
|
|
@@:
|
|
; Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
|
|
; s->compressed_len-7*last));
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Save the match info and tally the frequency counts. Return true if
|
|
; the current block must be flushed.
|
|
|
|
;int (s, dist, lc)
|
|
; deflate_state* s
|
|
; unsigned dist ;distance of matched string
|
|
; unsigned lc ;match length-MIN_MATCH or unmatched char (if dist==0)
|
|
align 4
|
|
proc _tr_tally uses ebx edi, s:dword, dist:dword, lc:dword
|
|
mov edi,[s]
|
|
zlib_debug '_tr_tally'
|
|
mov eax,[edi+deflate_state.last_lit]
|
|
shl eax,1
|
|
add eax,[edi+deflate_state.d_buf]
|
|
mov ebx,[dist]
|
|
mov word[eax],bx
|
|
mov eax,[edi+deflate_state.last_lit]
|
|
add eax,[edi+deflate_state.l_buf]
|
|
mov ebx,[lc]
|
|
mov byte[eax],bl
|
|
inc dword[edi+deflate_state.last_lit]
|
|
cmp dword[dist],0
|
|
jne @f ;if (..==0)
|
|
; lc is the unmatched char
|
|
mov eax,[lc]
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
inc word[eax+deflate_state.dyn_ltree+Freq]
|
|
jmp .end0
|
|
@@: ;else
|
|
inc dword[edi+deflate_state.matches]
|
|
; Here, lc is the match length - MIN_MATCH
|
|
dec dword[dist] ;dist = match distance - 1
|
|
MAX_DIST edi
|
|
cmp word[dist],ax
|
|
jge @f
|
|
cmp word[lc],MAX_MATCH-MIN_MATCH
|
|
jg @f
|
|
d_code [dist]
|
|
cmp ax,D_CODES
|
|
jl .end2
|
|
@@:
|
|
zlib_assert '_tr_tally: bad match' ;Assert(..<.. && ..<=.. && ..<..)
|
|
.end2:
|
|
mov eax,[lc]
|
|
add eax,_length_code
|
|
movzx eax,byte[eax]
|
|
add eax,LITERALS+1
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.dyn_ltree+Freq
|
|
inc word[eax]
|
|
d_code [dist]
|
|
imul eax,sizeof.ct_data
|
|
add eax,edi
|
|
add eax,deflate_state.dyn_dtree+Freq
|
|
inc word[eax]
|
|
.end0:
|
|
|
|
if TRUNCATE_BLOCK eq 1
|
|
; Try to guess if it is profitable to stop the current block here
|
|
mov eax,[edi+deflate_state.last_lit]
|
|
and eax,0x1fff
|
|
cmp eax,0
|
|
jne .end1
|
|
cmp word[edi+deflate_state.level],2
|
|
jle .end1 ;if (..==.. && ..>..)
|
|
; Compute an upper bound for the compressed length
|
|
; ulg out_length = (ulg)s->last_lit*8L;
|
|
; ulg in_length = (ulg)((long)s->strstart - s->block_start);
|
|
; int dcode;
|
|
; for (dcode = 0; dcode < D_CODES; dcode++) {
|
|
; out_length += (ulg)s->dyn_dtree[dcode].Freq *
|
|
; (5L+extra_dbits[dcode]);
|
|
; }
|
|
; out_length >>= 3;
|
|
; Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
|
|
; s->last_lit, in_length, out_length,
|
|
; 100L - out_length*100L/in_length));
|
|
; if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
|
|
.end1:
|
|
end if
|
|
mov ebx,[edi+deflate_state.last_lit]
|
|
mov edi,[edi+deflate_state.lit_bufsize]
|
|
dec edi
|
|
xor eax,eax
|
|
cmp ebx,edi
|
|
jne @f
|
|
inc eax ;return (..==..)
|
|
@@:
|
|
; 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.
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Send the block data compressed using the given Huffman trees
|
|
|
|
;void (s, ltree, dtree)
|
|
; deflate_state* s;
|
|
; ct_data *ltree ;literal tree
|
|
; ct_data *dtree ;distance tree
|
|
align 4
|
|
proc compress_block uses eax edi, s:dword, ltree:dword, dtree:dword
|
|
locals
|
|
dist dd ? ;unsigned ;distance of matched string
|
|
lc dd ? ;int ;match length or unmatched char (if dist == 0)
|
|
lx dd 0 ;unsigned ;running index in l_buf
|
|
u_code dd ? ;unsigned ;the code to send
|
|
extra dd ? ;int ;number of extra bits to send
|
|
endl
|
|
mov edi,[s]
|
|
cmp dword[edi+deflate_state.last_lit],0
|
|
je .end0 ;if (..!=0)
|
|
.cycle0: ; do
|
|
mov eax,[lx]
|
|
shl eax,1
|
|
add eax,[edi+deflate_state.d_buf]
|
|
movzx eax,word[eax]
|
|
mov [dist],eax
|
|
mov eax,[lx]
|
|
add eax,[edi+deflate_state.l_buf]
|
|
movzx eax,byte[eax]
|
|
mov [lc],eax
|
|
inc dword[lx]
|
|
cmp dword[dist],0
|
|
jne @f ;if (..==0)
|
|
send_code edi, [lc], [ltree] ;send a literal byte
|
|
; Tracecv(isgraph(lc), (stderr," '%c' ", lc));
|
|
jmp .end1
|
|
@@: ;else
|
|
; Here, lc is the match length - MIN_MATCH
|
|
mov eax,[lc]
|
|
add eax,_length_code
|
|
movzx eax,byte[eax]
|
|
mov [u_code],eax
|
|
add eax,LITERALS+1
|
|
send_code edi, eax, [ltree] ;send the length code
|
|
mov eax,[u_code]
|
|
shl eax,2
|
|
add eax,extra_lbits
|
|
mov eax,[eax]
|
|
mov [extra],eax
|
|
cmp eax,0
|
|
je @f ;if (..!=0)
|
|
mov eax,[u_code]
|
|
shl eax,2
|
|
add eax,base_length
|
|
mov eax,[eax]
|
|
sub [lc],eax
|
|
stdcall send_bits, edi, [lc], [extra] ;send the extra length bits
|
|
@@:
|
|
dec dword[dist] ;dist is now the match distance - 1
|
|
d_code [dist]
|
|
mov [u_code],eax
|
|
cmp eax,D_CODES
|
|
jl @f
|
|
zlib_assert 'bad d_code' ;Assert(..<..)
|
|
@@:
|
|
send_code edi, [u_code], [dtree] ;send the distance code
|
|
mov eax,[u_code]
|
|
shl eax,2
|
|
add eax,extra_dbits
|
|
mov eax,[eax]
|
|
mov [extra],eax
|
|
cmp eax,0
|
|
je .end1 ;if (..!=0)
|
|
mov eax,[u_code]
|
|
shl eax,2
|
|
add eax,base_dist
|
|
mov eax,[eax]
|
|
sub [dist],eax
|
|
stdcall send_bits, edi, [dist], [extra] ;send the extra distance bits
|
|
.end1: ;literal or match pair ?
|
|
|
|
; Check that the overlay between pending_buf and d_buf+l_buf is ok:
|
|
mov eax,[lx]
|
|
shl eax,1
|
|
add eax,[edi+deflate_state.lit_bufsize]
|
|
cmp word[edi+deflate_state.pending],ax
|
|
jl @f
|
|
zlib_assert 'pendingBuf overflow' ;Assert(..<..)
|
|
@@:
|
|
mov eax,[edi+deflate_state.last_lit]
|
|
cmp [lx],eax
|
|
jl .cycle0 ;while (..<..)
|
|
align 4
|
|
.end0:
|
|
|
|
send_code edi, END_BLOCK, [ltree]
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Check if the data type is TEXT or BINARY, using the following algorithm:
|
|
; - TEXT if the two conditions below are satisfied:
|
|
; a) There are no non-portable control characters belonging to the
|
|
; "black list" (0..6, 14..25, 28..31).
|
|
; b) There is at least one printable character belonging to the
|
|
; "white list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
|
|
; - BINARY otherwise.
|
|
; - The following partially-portable control characters form a
|
|
; "gray list" that is ignored in this detection algorithm:
|
|
; (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
|
|
; IN assertion: the fields Freq of dyn_ltree are set.
|
|
|
|
;int (s)
|
|
; deflate_state* s
|
|
align 4
|
|
proc detect_data_type uses ebx ecx edi, s:dword
|
|
; black_mask is the bit mask of black-listed bytes
|
|
; set bits 0..6, 14..25, and 28..31
|
|
; 0xf3ffc07f = binary 11110011111111111100000001111111
|
|
locals
|
|
black_mask dd 0xf3ffc07f
|
|
endl
|
|
mov edi,[s]
|
|
zlib_debug 'detect_data_type'
|
|
|
|
; Check for non-textual ("black-listed") bytes.
|
|
xor ecx,ecx
|
|
mov ebx,edi
|
|
add ebx,deflate_state.dyn_ltree+Freq
|
|
.cycle0:
|
|
cmp ecx,31
|
|
jg .cycle0end ;for (..;..<=..;..,..)
|
|
bt dword[black_mask],0
|
|
jnc @f
|
|
cmp word[ebx],0
|
|
je @f ;if (..&.. && ..!=0)
|
|
mov eax,Z_BINARY
|
|
jmp .end_f
|
|
@@:
|
|
shr dword[black_mask],1
|
|
add ebx,sizeof.ct_data
|
|
inc ecx
|
|
jmp .cycle0
|
|
.cycle0end:
|
|
|
|
; Check for textual ("white-listed") bytes.
|
|
mov ebx,edi
|
|
add ebx,deflate_state.dyn_ltree+Freq+9*sizeof.ct_data
|
|
cmp word[ebx],0
|
|
jne @f
|
|
add ebx,sizeof.ct_data
|
|
cmp word[ebx],0
|
|
jne @f
|
|
add ebx,3*sizeof.ct_data
|
|
cmp word[ebx],0
|
|
je .end0
|
|
@@: ;if (..!=0 || ..!=0 || ..!= 0)
|
|
mov eax,Z_TEXT
|
|
jmp .end_f
|
|
.end0:
|
|
mov ecx,32
|
|
mov ebx,edi
|
|
add ebx,deflate_state.dyn_ltree+Freq
|
|
.cycle1:
|
|
cmp ecx,LITERALS
|
|
jge .cycle1end ;for (..;..<..;..,..)
|
|
cmp word[ebx],0
|
|
je @f ;if (..!=0)
|
|
mov eax,Z_TEXT
|
|
jmp .end_f
|
|
@@:
|
|
add ebx,sizeof.ct_data
|
|
inc ecx
|
|
jmp .cycle1
|
|
.cycle1end:
|
|
|
|
; There are no "black-listed" or "white-listed" bytes:
|
|
; this stream either is empty or has tolerated ("gray-listed") bytes only.
|
|
|
|
mov eax,Z_BINARY
|
|
.end_f:
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Reverse the first len bits of a code, using straightforward code (a faster
|
|
; method would use a table)
|
|
; IN assertion: 1 <= len <= 15
|
|
|
|
;unsigned (code, len)
|
|
; unsigned code ;the value to invert
|
|
; int len ;its bit length
|
|
align 4
|
|
proc bi_reverse uses ebx, p1code:dword, len:dword
|
|
zlib_debug 'bi_reverse'
|
|
xor eax,eax
|
|
@@: ;do
|
|
mov ebx,[p1code]
|
|
and ebx,1
|
|
or eax,ebx
|
|
shr dword[p1code],1
|
|
shl eax,1
|
|
dec dword[len]
|
|
cmp dword[len],0
|
|
jg @b ;while (..>..)
|
|
shl eax,1
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Flush the bit buffer, keeping at most 7 bits in it.
|
|
|
|
;void (s)
|
|
; deflate_state* s
|
|
align 4
|
|
proc bi_flush uses eax ecx edi, s:dword
|
|
mov edi,[s]
|
|
cmp dword[edi+deflate_state.bi_valid],16
|
|
jne @f ;if (..==..)
|
|
mov cx,[edi+deflate_state.bi_buf]
|
|
put_short edi,cx
|
|
mov word[edi+deflate_state.bi_buf],0
|
|
mov dword[edi+deflate_state.bi_valid],0
|
|
jmp .end0
|
|
@@: ;else if (..>=..)
|
|
cmp dword[edi+deflate_state.bi_valid],8
|
|
jl .end0
|
|
mov cl,byte[edi+deflate_state.bi_buf]
|
|
put_byte edi,cl
|
|
shr word[edi+deflate_state.bi_buf],8
|
|
sub dword[edi+deflate_state.bi_valid],8
|
|
.end0:
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Flush the bit buffer and align the output on a byte boundary
|
|
|
|
;void (s)
|
|
; deflate_state* s
|
|
align 4
|
|
proc bi_windup uses eax ecx edi, s:dword
|
|
mov edi,[s]
|
|
cmp dword[edi+deflate_state.bi_valid],8
|
|
jle @f ;if (..>..)
|
|
mov cx,[edi+deflate_state.bi_buf]
|
|
put_short edi, cx
|
|
jmp .end0
|
|
@@: ;else if (..>0)
|
|
cmp dword[edi+deflate_state.bi_valid],0
|
|
jle .end0
|
|
mov cl,byte[edi+deflate_state.bi_buf]
|
|
put_byte edi, cl
|
|
.end0:
|
|
mov word[edi+deflate_state.bi_buf],0
|
|
mov dword[edi+deflate_state.bi_valid],0
|
|
if DEBUG eq 1
|
|
mov eax,[edi+deflate_state.bits_sent]
|
|
add eax,7
|
|
and eax,not 7
|
|
mov [edi+deflate_state.bits_sent],eax
|
|
end if
|
|
ret
|
|
endp
|
|
|
|
; ===========================================================================
|
|
; Copy a stored block, storing first the length and its
|
|
; one's complement if requested.
|
|
|
|
;void (s, buf, len, header)
|
|
; deflate_state* s
|
|
; charf *buf ;the input data
|
|
; unsigned len ;its length
|
|
; int header ;true if block header must be written
|
|
align 4
|
|
proc copy_block uses eax ebx ecx edi esi, s:dword, buf:dword, len:dword, p4header:dword
|
|
mov edi,[s]
|
|
stdcall bi_windup,edi ;align on byte boundary
|
|
|
|
cmp dword[p4header],0
|
|
je @f ;if (..)
|
|
mov ecx,[len]
|
|
put_short edi, cx
|
|
not cx
|
|
put_short edi, cx
|
|
if DEBUG eq 1
|
|
add dword[edi+deflate_state.bits_sent],2*16
|
|
end if
|
|
@@:
|
|
if DEBUG eq 1
|
|
mov ecx,[len]
|
|
shl ecx,3
|
|
add [edi+deflate_state.bits_sent],ecx
|
|
end if
|
|
mov ecx,[len]
|
|
mov esi,[buf]
|
|
@@: ;while (len--)
|
|
lodsb
|
|
mov bl,al
|
|
put_byte edi, bl
|
|
loop @b
|
|
ret
|
|
endp
|