trees.cc File Reference

#include "deflate.h"

Go to the source code of this file.

Data Structures

struct  static_tree_desc_s

Defines

#define MAX_BL_BITS   7
#define END_BLOCK   256
#define REP_3_6   16
#define REPZ_3_10   17
#define REPZ_11_138   18
#define Buf_size   (8 * 2*sizeof(char))
#define DIST_CODE_LEN   512
#define send_code(s, c, tree)   send_bits(s, tree[c].Code, tree[c].Len)
#define put_short(s, w)
#define send_bits(s, value, length)
#define SMALLEST   1
#define pqremove(s, tree, top)
#define smaller(tree, n, m, depth)

Functions

local void tr_static_init OF ((void))
local void init_block OF ((deflate_state *s))
local void pqdownheap OF ((deflate_state *s, ct_data *tree, int k))
local void gen_bitlen OF ((deflate_state *s, tree_desc *desc))
local void gen_codes OF ((ct_data *tree, int max_code, ushf *bl_count))
local void scan_tree OF ((deflate_state *s, ct_data *tree, int max_code))
local void send_all_trees OF ((deflate_state *s, int lcodes, int dcodes, int blcodes))
local void compress_block OF ((deflate_state *s, ct_data *ltree, ct_data *dtree))
local unsigned bi_reverse OF ((unsigned value, int length))
local void copy_block OF ((deflate_state *s, charf *buf, unsigned len, int header))
local void tr_static_init ()
void _tr_init (deflate_state *s)
local void init_block (deflate_state *s)
local void pqdownheap (deflate_state *s, ct_data *tree, int k)
local void gen_bitlen (deflate_state *s, tree_desc *desc)
local void gen_codes (ct_data *tree, int max_code, ushf *bl_count)
local void build_tree (deflate_state *s, tree_desc *desc)
local void scan_tree (deflate_state *s, ct_data *tree, int max_code)
local void send_tree (deflate_state *s, ct_data *tree, int max_code)
local int build_bl_tree (deflate_state *s)
local void send_all_trees (deflate_state *s, int lcodes, int dcodes, int blcodes)
void _tr_stored_block (deflate_state *s, charf *buf, ulg stored_len, int eof)
void _tr_align (deflate_state *s)
void _tr_flush_block (deflate_state *s, charf *buf, ulg stored_len, int eof)
int _tr_tally (deflate_state *s, unsigned dist, unsigned lc)
local void compress_block (deflate_state *s, ct_data *ltree, ct_data *dtree)
local void set_data_type (deflate_state *s)
local unsigned bi_reverse (unsigned code, int len)
local void bi_flush (deflate_state *s)
local void bi_windup (deflate_state *s)
local void copy_block (deflate_state *s, charf *buf, unsigned len, int header)

Variables

local const int extra_lbits [LENGTH_CODES] = {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 int extra_dbits [D_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}
local const int extra_blbits [BL_CODES] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}
local const uch bl_order [BL_CODES] = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}
local ct_data static_ltree [L_CODES+2]
local ct_data static_dtree [D_CODES]
uch _dist_code [DIST_CODE_LEN]
uch _length_code [MAX_MATCH-MIN_MATCH+1]
local int base_length [LENGTH_CODES]
local int base_dist [D_CODES]
local static_tree_desc static_l_desc
local static_tree_desc static_d_desc
local static_tree_desc static_bl_desc


Define Documentation

#define Buf_size   (8 * 2*sizeof(char))

Definition at line 76 of file trees.cc.

#define DIST_CODE_LEN   512

Definition at line 85 of file trees.cc.

#define END_BLOCK   256

Definition at line 49 of file trees.cc.

Referenced by _tr_align(), compress_block(), and init_block().

#define MAX_BL_BITS   7

Definition at line 46 of file trees.cc.

#define pqremove ( s,
tree,
top   ) 

Value:

{\
    top = s->heap[SMALLEST]; \
    s->heap[SMALLEST] = s->heap[s->heap_len--]; \
    pqdownheap(s, tree, SMALLEST); \
}

Definition at line 429 of file trees.cc.

#define put_short ( s,
 ) 

Value:

{ \
    put_byte(s, (uch)((w) & 0xff)); \
    put_byte(s, (uch)((ush)(w) >> 8)); \
}

Definition at line 180 of file trees.cc.

Referenced by bi_flush(), bi_windup(), and copy_block().

#define REP_3_6   16

Definition at line 52 of file trees.cc.

Referenced by scan_tree(), and send_tree().

#define REPZ_11_138   18

Definition at line 58 of file trees.cc.

Referenced by scan_tree(), and send_tree().

#define REPZ_3_10   17

Definition at line 55 of file trees.cc.

Referenced by scan_tree(), and send_tree().

#define send_bits ( s,
value,
length   ) 

Value:

{ int len = length;\
  if (s->bi_valid > (int)Buf_size - len) {\
    int val = value;\
    s->bi_buf |= (val << s->bi_valid);\
    put_short(s, s->bi_buf);\
    s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
    s->bi_valid += len - Buf_size;\
  } else {\
    s->bi_buf |= (value) << s->bi_valid;\
    s->bi_valid += len;\
  }\
}

Definition at line 214 of file trees.cc.

Referenced by _tr_align(), _tr_flush_block(), _tr_stored_block(), compress_block(), send_all_trees(), and send_tree().

#define send_code ( s,
c,
tree   )     send_bits(s, tree[c].Code, tree[c].Len)

Definition at line 167 of file trees.cc.

Referenced by _tr_align(), compress_block(), and send_tree().

#define smaller ( tree,
n,
m,
depth   ) 

Value:

(tree[n].Freq < tree[m].Freq || \
   (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))

Definition at line 440 of file trees.cc.

Referenced by pqdownheap().

#define SMALLEST   1

Definition at line 421 of file trees.cc.


Function Documentation

void _tr_align ( deflate_state *  s  ) 

Definition at line 864 of file trees.cc.

References bi_flush(), END_BLOCK, send_bits, send_code, and static_ltree.

Referenced by deflate().

00865 {
00866     send_bits(s, STATIC_TREES<<1, 3);
00867     send_code(s, END_BLOCK, static_ltree);
00868 #ifdef DEBUG
00869     s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
00870 #endif
00871     bi_flush(s);
00872     /* Of the 10 bits for the empty block, we have already sent
00873      * (10 - bi_valid) bits. The lookahead for the last real code (before
00874      * the EOB of the previous block) was thus at least one plus the length
00875      * of the EOB plus what we have just sent of the empty static block.
00876      */
00877     if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
00878         send_bits(s, STATIC_TREES<<1, 3);
00879         send_code(s, END_BLOCK, static_ltree);
00880 #ifdef DEBUG
00881         s->compressed_len += 10L;
00882 #endif
00883         bi_flush(s);
00884     }
00885     s->last_eob_len = 7;
00886 }

void _tr_flush_block ( deflate_state *  s,
charf *  buf,
ulg  stored_len,
int  eof 
)

Definition at line 892 of file trees.cc.

References _tr_stored_block(), bi_windup(), build_bl_tree(), build_tree(), compress_block(), init_block(), send_all_trees(), send_bits, set_data_type(), static_dtree, and static_ltree.

00893 {
00894     ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
00895     int max_blindex = 0;  /* index of last bit length code of non zero freq */
00896 
00897     /* Build the Huffman trees unless a stored block is forced */
00898     if (s->level > 0) {
00899 
00900          /* Check if the file is ascii or binary */
00901         if (s->strm->data_type == Z_UNKNOWN) set_data_type(s);
00902 
00903         /* Construct the literal and distance trees */
00904         build_tree(s, (tree_desc *)(&(s->l_desc)));
00905         Tracev((stderr, (char*)"\nlit data: dyn %ld, stat %ld", s->opt_len,
00906                 s->static_len));
00907 
00908         build_tree(s, (tree_desc *)(&(s->d_desc)));
00909         Tracev((stderr, (char*)"\ndist data: dyn %ld, stat %ld", s->opt_len,
00910                 s->static_len));
00911         /* At this point, opt_len and static_len are the total bit lengths of
00912          * the compressed block data, excluding the tree representations.
00913          */
00914 
00915         /* Build the bit length tree for the above two trees, and get the index
00916          * in bl_order of the last bit length code to send.
00917          */
00918         max_blindex = build_bl_tree(s);
00919 
00920         /* Determine the best encoding. Compute the block lengths in bytes. */
00921         opt_lenb = (s->opt_len+3+7)>>3;
00922         static_lenb = (s->static_len+3+7)>>3;
00923 
00924         Tracev((stderr, (char*)"\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
00925                 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
00926                 s->last_lit));
00927 
00928         if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
00929 
00930     } else {
00931         Assert(buf != (char*)0, (char*)"lost buf");
00932         opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
00933     }
00934 
00935 #ifdef FORCE_STORED
00936     if (buf != (char*)0) { /* force stored block */
00937 #else
00938     if (stored_len+4 <= opt_lenb && buf != (char*)0) {
00939                        /* 4: two words for the lengths */
00940 #endif
00941         /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
00942          * Otherwise we can't have processed more than WSIZE input bytes since
00943          * the last block flush, because compression would have been
00944          * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
00945          * transform a block into a stored block.
00946          */
00947         _tr_stored_block(s, buf, stored_len, eof);
00948 
00949 #ifdef FORCE_STATIC
00950     } else if (static_lenb >= 0) { /* force static trees */
00951 #else
00952     } else if (static_lenb == opt_lenb) {
00953 #endif
00954         send_bits(s, (STATIC_TREES<<1)+eof, 3);
00955         compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
00956 #ifdef DEBUG
00957         s->compressed_len += 3 + s->static_len;
00958 #endif
00959     } else {
00960         send_bits(s, (DYN_TREES<<1)+eof, 3);
00961         send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
00962                        max_blindex+1);
00963         compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
00964 #ifdef DEBUG
00965         s->compressed_len += 3 + s->opt_len;
00966 #endif
00967     }
00968     Assert (s->compressed_len == s->bits_sent, (char*)"bad compressed size");
00969     /* The above check is made mod 2^32, for files larger than 512 MB
00970      * and uLong implemented on 32 bits.
00971      */
00972     init_block(s);
00973 
00974     if (eof) {
00975         bi_windup(s);
00976 #ifdef DEBUG
00977         s->compressed_len += 7;  /* align on byte boundary */
00978 #endif
00979     }
00980     Tracev((stderr,(char*)"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
00981            s->compressed_len-7*eof));
00982 }

void _tr_init ( deflate_state *  s  ) 

Definition at line 379 of file trees.cc.

References init_block(), static_bl_desc, static_d_desc, static_l_desc, and tr_static_init().

Referenced by deflateReset().

00380 {
00381     tr_static_init();
00382 
00383     s->l_desc.dyn_tree = s->dyn_ltree;
00384     s->l_desc.stat_desc = &static_l_desc;
00385 
00386     s->d_desc.dyn_tree = s->dyn_dtree;
00387     s->d_desc.stat_desc = &static_d_desc;
00388 
00389     s->bl_desc.dyn_tree = s->bl_tree;
00390     s->bl_desc.stat_desc = &static_bl_desc;
00391 
00392     s->bi_buf = 0;
00393     s->bi_valid = 0;
00394     s->last_eob_len = 8; /* enough lookahead for inflate */
00395 #ifdef DEBUG
00396     s->compressed_len = 0L;
00397     s->bits_sent = 0L;
00398 #endif
00399 
00400     /* Initialize the first block of the first file: */
00401     init_block(s);
00402 }

void _tr_stored_block ( deflate_state *  s,
charf *  buf,
ulg  stored_len,
int  eof 
)

Definition at line 843 of file trees.cc.

References copy_block(), and send_bits.

Referenced by _tr_flush_block(), and deflate().

00844 {
00845     send_bits(s, (STORED_BLOCK<<1)+eof, 3);  /* send block type */
00846 #ifdef DEBUG
00847     s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
00848     s->compressed_len += (stored_len + 4) << 3;
00849 #endif
00850     copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
00851 }

int _tr_tally ( deflate_state *  s,
unsigned  dist,
unsigned  lc 
)

Definition at line 988 of file trees.cc.

References _length_code, and extra_dbits.

00989 {
00990     s->d_buf[s->last_lit] = (ush)dist;
00991     s->l_buf[s->last_lit++] = (uch)lc;
00992     if (dist == 0) {
00993         /* lc is the unmatched char */
00994         s->dyn_ltree[lc].Freq++;
00995     } else {
00996         s->matches++;
00997         /* Here, lc is the match length - MIN_MATCH */
00998         dist--;             /* dist = match distance - 1 */
00999         Assert((ush)dist < (ush)MAX_DIST(s) &&
01000                (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
01001                (ush)d_code(dist) < (ush)D_CODES,  (char*)"_tr_tally: bad match");
01002 
01003         s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
01004         s->dyn_dtree[d_code(dist)].Freq++;
01005     }
01006 
01007 #ifdef TRUNCATE_BLOCK
01008     /* Try to guess if it is profitable to stop the current block here */
01009     if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
01010         /* Compute an upper bound for the compressed length */
01011         ulg out_length = (ulg)s->last_lit*8L;
01012         ulg in_length = (ulg)((long)s->strstart - s->block_start);
01013         int dcode;
01014         for (dcode = 0; dcode < D_CODES; dcode++) {
01015             out_length += (ulg)s->dyn_dtree[dcode].Freq *
01016                 (5L+extra_dbits[dcode]);
01017         }
01018         out_length >>= 3;
01019         Tracev((stderr,(char*)"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
01020                s->last_lit, in_length, out_length,
01021                100L - out_length*100L/in_length));
01022         if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
01023     }
01024 #endif
01025     return (s->last_lit == s->lit_bufsize-1);
01026     /* We avoid equality with lit_bufsize because of wraparound at 64K
01027      * on 16 bit machines and because stored blocks are restricted to
01028      * 64K-1 bytes.
01029      */
01030 }

local void bi_flush ( deflate_state *  s  ) 

Definition at line 1115 of file trees.cc.

References put_short.

Referenced by _tr_align().

01116 {
01117     if (s->bi_valid == 16) {
01118         put_short(s, s->bi_buf);
01119         s->bi_buf = 0;
01120         s->bi_valid = 0;
01121     } else if (s->bi_valid >= 8) {
01122         put_byte(s, (Byte)s->bi_buf);
01123         s->bi_buf >>= 8;
01124         s->bi_valid -= 8;
01125     }
01126 }

local unsigned bi_reverse ( unsigned  code,
int  len 
)

Definition at line 1102 of file trees.cc.

Referenced by gen_codes(), and tr_static_init().

01103 {
01104     register unsigned res = 0;
01105     do {
01106         res |= code & 1;
01107         code >>= 1, res <<= 1;
01108     } while (--len > 0);
01109     return res >> 1;
01110 }

local void bi_windup ( deflate_state *  s  ) 

Definition at line 1131 of file trees.cc.

References put_short.

Referenced by _tr_flush_block(), and copy_block().

01132 {
01133     if (s->bi_valid > 8) {
01134         put_short(s, s->bi_buf);
01135     } else if (s->bi_valid > 0) {
01136         put_byte(s, (Byte)s->bi_buf);
01137     }
01138     s->bi_buf = 0;
01139     s->bi_valid = 0;
01140 #ifdef DEBUG
01141     s->bits_sent = (s->bits_sent+7) & ~7;
01142 #endif
01143 }

local int build_bl_tree ( deflate_state *  s  ) 

Definition at line 782 of file trees.cc.

References bl_order, build_tree(), and scan_tree().

Referenced by _tr_flush_block().

00783 {
00784     int max_blindex;  /* index of last bit length code of non zero freq */
00785 
00786     /* Determine the bit length frequencies for literal and distance trees */
00787     scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
00788     scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
00789 
00790     /* Build the bit length tree: */
00791     build_tree(s, (tree_desc *)(&(s->bl_desc)));
00792     /* opt_len now includes the length of the tree representations, except
00793      * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
00794      */
00795 
00796     /* Determine the number of bit length codes to send. The pkzip format
00797      * requires that at least 4 bit length codes be sent. (appnote.txt says
00798      * 3 but the actual value used is 4.)
00799      */
00800     for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
00801         if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
00802     }
00803     /* Update opt_len to include the bit length tree and counts */
00804     s->opt_len += 3*(max_blindex+1) + 5+5+4;
00805     Tracev((stderr, (char*)"\ndyn trees: dyn %ld, stat %ld",
00806             s->opt_len, s->static_len));
00807 
00808     return max_blindex;
00809 }

local void build_tree ( deflate_state *  s,
tree_desc *  desc 
)

Definition at line 606 of file trees.cc.

References CLHEP::detail::n.

Referenced by _tr_flush_block(), and build_bl_tree().

00607 {
00608     ct_data *tree         = desc->dyn_tree;
00609     const ct_data *stree  = desc->stat_desc->static_tree;
00610     int elems             = desc->stat_desc->elems;
00611     int n, m;          /* iterate over heap elements */
00612     int max_code = -1; /* largest code with non zero frequency */
00613     int node;          /* new node being created */
00614 
00615     /* Construct the initial heap, with least frequent element in
00616      * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
00617      * heap[0] is not used.
00618      */
00619     s->heap_len = 0, s->heap_max = HEAP_SIZE;
00620 
00621     for (n = 0; n < elems; n++) {
00622         if (tree[n].Freq != 0) {
00623             s->heap[++(s->heap_len)] = max_code = n;
00624             s->depth[n] = 0;
00625         } else {
00626             tree[n].Len = 0;
00627         }
00628     }
00629 
00630     /* The pkzip format requires that at least one distance code exists,
00631      * and that at least one bit should be sent even if there is only one
00632      * possible code. So to avoid special checks later on we force at least
00633      * two codes of non zero frequency.
00634      */
00635     while (s->heap_len < 2) {
00636         node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
00637         tree[node].Freq = 1;
00638         s->depth[node] = 0;
00639         s->opt_len--; if (stree) s->static_len -= stree[node].Len;
00640         /* node is 0 or 1 so it does not have extra bits */
00641     }
00642     desc->max_code = max_code;
00643 
00644     /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
00645      * establish sub-heaps of increasing lengths:
00646      */
00647     for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
00648 
00649     /* Construct the Huffman tree by repeatedly combining the least two
00650      * frequent nodes.
00651      */
00652     node = elems;              /* next internal node of the tree */
00653     do {
00654         pqremove(s, tree, n);  /* n = node of least frequency */
00655         m = s->heap[SMALLEST]; /* m = node of next least frequency */
00656 
00657         s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
00658         s->heap[--(s->heap_max)] = m;
00659 
00660         /* Create a new node father of n and m */
00661         tree[node].Freq = tree[n].Freq + tree[m].Freq;
00662         s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ?
00663                                 s->depth[n] : s->depth[m]) + 1);
00664         tree[n].Dad = tree[m].Dad = (ush)node;
00665 #ifdef DUMP_BL_TREE
00666         if (tree == s->bl_tree) {
00667             fprintf(stderr,(char*)"\nnode %d(%d), sons %d(%d) %d(%d)",
00668                     node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
00669         }
00670 #endif
00671         /* and insert the new node in the heap */
00672         s->heap[SMALLEST] = node++;
00673         pqdownheap(s, tree, SMALLEST);
00674 
00675     } while (s->heap_len >= 2);
00676 
00677     s->heap[--(s->heap_max)] = s->heap[SMALLEST];
00678 
00679     /* At this point, the fields freq and dad are set. We can now
00680      * generate the bit lengths.
00681      */
00682     gen_bitlen(s, (tree_desc *)desc);
00683 
00684     /* The field len is now set, we can generate the bit codes */
00685     gen_codes ((ct_data *)tree, max_code, s->bl_count);
00686 }

local void compress_block ( deflate_state *  s,
ct_data *  ltree,
ct_data *  dtree 
)

Definition at line 1035 of file trees.cc.

References _length_code, base_dist, base_length, END_BLOCK, extra_dbits, extra_lbits, send_bits, and send_code.

Referenced by _tr_flush_block().

01036 {
01037     unsigned dist;      /* distance of matched string */
01038     int lc;             /* match length or unmatched char (if dist == 0) */
01039     unsigned lx = 0;    /* running index in l_buf */
01040     unsigned code;      /* the code to send */
01041     int extra;          /* number of extra bits to send */
01042 
01043     if (s->last_lit != 0) do {
01044         dist = s->d_buf[lx];
01045         lc = s->l_buf[lx++];
01046         if (dist == 0) {
01047             send_code(s, lc, ltree); /* send a literal byte */
01048             Tracecv(isgraph(lc), (stderr," '%c' ", lc));
01049         } else {
01050             /* Here, lc is the match length - MIN_MATCH */
01051             code = _length_code[lc];
01052             send_code(s, code+LITERALS+1, ltree); /* send the length code */
01053             extra = extra_lbits[code];
01054             if (extra != 0) {
01055                 lc -= base_length[code];
01056                 send_bits(s, lc, extra);       /* send the extra length bits */
01057             }
01058             dist--; /* dist is now the match distance - 1 */
01059             code = d_code(dist);
01060             Assert (code < D_CODES, (char*)"bad d_code");
01061 
01062             send_code(s, code, dtree);       /* send the distance code */
01063             extra = extra_dbits[code];
01064             if (extra != 0) {
01065                 dist -= base_dist[code];
01066                 send_bits(s, dist, extra);   /* send the extra distance bits */
01067             }
01068         } /* literal or match pair ? */
01069 
01070         /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
01071         Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx,
01072                (char*)"pendingBuf overflow");
01073 
01074     } while (lx < s->last_lit);
01075 
01076     send_code(s, END_BLOCK, ltree);
01077     s->last_eob_len = ltree[END_BLOCK].Len;
01078 }

local void copy_block ( deflate_state *  s,
charf *  buf,
unsigned  len,
int  header 
)

Definition at line 1149 of file trees.cc.

References bi_windup(), and put_short.

Referenced by _tr_stored_block().

01150 {
01151     bi_windup(s);        /* align on byte boundary */
01152     s->last_eob_len = 8; /* enough lookahead for inflate */
01153 
01154     if (header) {
01155         put_short(s, (ush)len);
01156         put_short(s, (ush)~len);
01157 #ifdef DEBUG
01158         s->bits_sent += 2*16;
01159 #endif
01160     }
01161 #ifdef DEBUG
01162     s->bits_sent += (ulg)len<<3;
01163 #endif
01164     while (len--) {
01165         put_byte(s, *buf++);
01166     }
01167 }

local void gen_bitlen ( deflate_state *  s,
tree_desc *  desc 
)

Definition at line 482 of file trees.cc.

References CLHEP::detail::n.

00483 {
00484     ct_data *tree        = desc->dyn_tree;
00485     int max_code         = desc->max_code;
00486     const ct_data *stree = desc->stat_desc->static_tree;
00487     const intf *extra    = desc->stat_desc->extra_bits;
00488     int base             = desc->stat_desc->extra_base;
00489     int max_length       = desc->stat_desc->max_length;
00490     int h;              /* heap index */
00491     int n, m;           /* iterate over the tree elements */
00492     int bits;           /* bit length */
00493     int xbits;          /* extra bits */
00494     ush f;              /* frequency */
00495     int overflow = 0;   /* number of elements with bit length too large */
00496 
00497     for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
00498 
00499     /* In a first pass, compute the optimal bit lengths (which may
00500      * overflow in the case of the bit length tree).
00501      */
00502     tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
00503 
00504     for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
00505         n = s->heap[h];
00506         bits = tree[tree[n].Dad].Len + 1;
00507         if (bits > max_length) bits = max_length, overflow++;
00508         tree[n].Len = (ush)bits;
00509         /* We overwrite tree[n].Dad which is no longer needed */
00510 
00511         if (n > max_code) continue; /* not a leaf node */
00512 
00513         s->bl_count[bits]++;
00514         xbits = 0;
00515         if (n >= base) xbits = extra[n-base];
00516         f = tree[n].Freq;
00517         s->opt_len += (ulg)f * (bits + xbits);
00518         if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
00519     }
00520     if (overflow == 0) return;
00521 
00522     Trace((stderr,(char*)"\nbit length overflow\n"));
00523     /* This happens for example on obj2 and pic of the Calgary corpus */
00524 
00525     /* Find the first bit length which could increase: */
00526     do {
00527         bits = max_length-1;
00528         while (s->bl_count[bits] == 0) bits--;
00529         s->bl_count[bits]--;      /* move one leaf down the tree */
00530         s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
00531         s->bl_count[max_length]--;
00532         /* The brother of the overflow item also moves one step up,
00533          * but this does not affect bl_count[max_length]
00534          */
00535         overflow -= 2;
00536     } while (overflow > 0);
00537 
00538     /* Now recompute all bit lengths, scanning in increasing frequency.
00539      * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
00540      * lengths instead of fixing only the wrong ones. This idea is taken
00541      * from 'ar' written by Haruhiko Okumura.)
00542      */
00543     for (bits = max_length; bits != 0; bits--) {
00544         n = s->bl_count[bits];
00545         while (n != 0) {
00546             m = s->heap[--h];
00547             if (m > max_code) continue;
00548             if (tree[m].Len != (unsigned) bits) {
00549                 Trace((stderr,(char*)"code %d bits %d->%d\n", m, tree[m].Len, bits));
00550                 s->opt_len += ((long)bits - (long)tree[m].Len)
00551                               *(long)tree[m].Freq;
00552                 tree[m].Len = (ush)bits;
00553             }
00554             n--;
00555         }
00556     }
00557 }

local void gen_codes ( ct_data *  tree,
int  max_code,
ushf *  bl_count 
)

Definition at line 567 of file trees.cc.

References bi_reverse(), CLHEP::detail::n, and static_ltree.

Referenced by tr_static_init().

00568 {
00569     ush next_code[MAX_BITS+1]; /* next code value for each bit length */
00570     ush code = 0;              /* running code value */
00571     int bits;                  /* bit index */
00572     int n;                     /* code index */
00573 
00574     /* The distribution counts are first used to generate the code values
00575      * without bit reversal.
00576      */
00577     for (bits = 1; bits <= MAX_BITS; bits++) {
00578         next_code[bits] = code = (code + bl_count[bits-1]) << 1;
00579     }
00580     /* Check that the bit counts in bl_count are consistent. The last code
00581      * must be all ones.
00582      */
00583     Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
00584             (char*)"inconsistent bit counts");
00585     Tracev((stderr,(char*)"\ngen_codes: max_code %d ", max_code));
00586 
00587     for (n = 0;  n <= max_code; n++) {
00588         int len = tree[n].Len;
00589         if (len == 0) continue;
00590         /* Now reverse the bits */
00591         tree[n].Code = bi_reverse(next_code[len]++, len);
00592 
00593         Tracecv(tree != static_ltree, (stderr,(char*)"\nn %3d %c l %2d c %4x (%x) ",
00594              n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
00595     }
00596 }

local void init_block ( deflate_state *  s  ) 

Definition at line 407 of file trees.cc.

References END_BLOCK, and CLHEP::detail::n.

Referenced by _tr_flush_block(), and _tr_init().

00408 {
00409     int n; /* iterates over tree elements */
00410 
00411     /* Initialize the trees. */
00412     for (n = 0; n < L_CODES;  n++) s->dyn_ltree[n].Freq = 0;
00413     for (n = 0; n < D_CODES;  n++) s->dyn_dtree[n].Freq = 0;
00414     for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
00415 
00416     s->dyn_ltree[END_BLOCK].Freq = 1;
00417     s->opt_len = s->static_len = 0L;
00418     s->last_lit = s->matches = 0;
00419 }

local void copy_block OF ( (deflate_state *s, charf *buf, unsigned len, int header)   ) 

local unsigned bi_reverse OF ( (unsigned value, int length)   ) 

local void compress_block OF ( (deflate_state *s, ct_data *ltree, ct_data *dtree)   ) 

local void send_all_trees OF ( (deflate_state *s, int lcodes, int dcodes, int blcodes)   ) 

local void scan_tree OF ( (deflate_state *s, ct_data *tree, int max_code)   ) 

local void gen_codes OF ( (ct_data *tree, int max_code, ushf *bl_count)   ) 

local void gen_bitlen OF ( (deflate_state *s, tree_desc *desc)   ) 

local void pqdownheap OF ( (deflate_state *s, ct_data *tree, int k)   ) 

local void init_block OF ( (deflate_state *s)   ) 

local void tr_static_init OF ( (void)   ) 

local void pqdownheap ( deflate_state *  s,
ct_data *  tree,
int  k 
)

Definition at line 450 of file trees.cc.

References smaller.

00451 {
00452     int v = s->heap[k];
00453     int j = k << 1;  /* left son of k */
00454     while (j <= s->heap_len) {
00455         /* Set j to the smallest of the two sons: */
00456         if (j < s->heap_len &&
00457             smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
00458             j++;
00459         }
00460         /* Exit if v is smaller than both sons */
00461         if (smaller(tree, v, s->heap[j], s->depth)) break;
00462 
00463         /* Exchange v with the smallest son */
00464         s->heap[k] = s->heap[j];  k = j;
00465 
00466         /* And continue down the tree, setting j to the left son of k */
00467         j <<= 1;
00468     }
00469     s->heap[k] = v;
00470 }

local void scan_tree ( deflate_state *  s,
ct_data *  tree,
int  max_code 
)

Definition at line 692 of file trees.cc.

References CLHEP::detail::n, REP_3_6, REPZ_11_138, and REPZ_3_10.

Referenced by build_bl_tree().

00693 {
00694     int n;                     /* iterates over all tree elements */
00695     int prevlen = -1;          /* last emitted length */
00696     int curlen;                /* length of current code */
00697     int nextlen = tree[0].Len; /* length of next code */
00698     int count = 0;             /* repeat count of the current code */
00699     int max_count = 7;         /* max repeat count */
00700     int min_count = 4;         /* min repeat count */
00701 
00702     if (nextlen == 0) max_count = 138, min_count = 3;
00703     tree[max_code+1].Len = (ush)0xffff; /* guard */
00704 
00705     for (n = 0; n <= max_code; n++) {
00706         curlen = nextlen; nextlen = tree[n+1].Len;
00707         if (++count < max_count && curlen == nextlen) {
00708             continue;
00709         } else if (count < min_count) {
00710             s->bl_tree[curlen].Freq += count;
00711         } else if (curlen != 0) {
00712             if (curlen != prevlen) s->bl_tree[curlen].Freq++;
00713             s->bl_tree[REP_3_6].Freq++;
00714         } else if (count <= 10) {
00715             s->bl_tree[REPZ_3_10].Freq++;
00716         } else {
00717             s->bl_tree[REPZ_11_138].Freq++;
00718         }
00719         count = 0; prevlen = curlen;
00720         if (nextlen == 0) {
00721             max_count = 138, min_count = 3;
00722         } else if (curlen == nextlen) {
00723             max_count = 6, min_count = 3;
00724         } else {
00725             max_count = 7, min_count = 4;
00726         }
00727     }
00728 }

local void send_all_trees ( deflate_state *  s,
int  lcodes,
int  dcodes,
int  blcodes 
)

Definition at line 816 of file trees.cc.

References bl_order, send_bits, and send_tree().

Referenced by _tr_flush_block().

00817 {
00818     int rank;                    /* index in bl_order */
00819 
00820     Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, (char*)"not enough codes");
00821     Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
00822             (char*)"too many codes");
00823     Tracev((stderr, (char*)"\nbl counts: "));
00824     send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
00825     send_bits(s, dcodes-1,   5);
00826     send_bits(s, blcodes-4,  4); /* not -3 as stated in appnote.txt */
00827     for (rank = 0; rank < blcodes; rank++) {
00828         Tracev((stderr, (char*)"\nbl code %2d ", bl_order[rank]));
00829         send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
00830     }
00831     Tracev((stderr, (char*)"\nbl tree: sent %ld", s->bits_sent));
00832 
00833     send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
00834     Tracev((stderr, (char*)"\nlit tree: sent %ld", s->bits_sent));
00835 
00836     send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
00837     Tracev((stderr, (char*)"\ndist tree: sent %ld", s->bits_sent));
00838 }

local void send_tree ( deflate_state *  s,
ct_data *  tree,
int  max_code 
)

Definition at line 734 of file trees.cc.

References CLHEP::detail::n, REP_3_6, REPZ_11_138, REPZ_3_10, send_bits, and send_code.

Referenced by send_all_trees().

00735 {
00736     int n;                     /* iterates over all tree elements */
00737     int prevlen = -1;          /* last emitted length */
00738     int curlen;                /* length of current code */
00739     int nextlen = tree[0].Len; /* length of next code */
00740     int count = 0;             /* repeat count of the current code */
00741     int max_count = 7;         /* max repeat count */
00742     int min_count = 4;         /* min repeat count */
00743 
00744     /* tree[max_code+1].Len = -1; */  /* guard already set */
00745     if (nextlen == 0) max_count = 138, min_count = 3;
00746 
00747     for (n = 0; n <= max_code; n++) {
00748         curlen = nextlen; nextlen = tree[n+1].Len;
00749         if (++count < max_count && curlen == nextlen) {
00750             continue;
00751         } else if (count < min_count) {
00752             do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
00753 
00754         } else if (curlen != 0) {
00755             if (curlen != prevlen) {
00756                 send_code(s, curlen, s->bl_tree); count--;
00757             }
00758             Assert(count >= 3 && count <= 6, (char*)" 3_6?");
00759             send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
00760 
00761         } else if (count <= 10) {
00762             send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
00763 
00764         } else {
00765             send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
00766         }
00767         count = 0; prevlen = curlen;
00768         if (nextlen == 0) {
00769             max_count = 138, min_count = 3;
00770         } else if (curlen == nextlen) {
00771             max_count = 6, min_count = 3;
00772         } else {
00773             max_count = 7, min_count = 4;
00774         }
00775     }
00776 }

local void set_data_type ( deflate_state *  s  ) 

Definition at line 1086 of file trees.cc.

References CLHEP::detail::n.

Referenced by _tr_flush_block().

01087 {
01088     int n = 0;
01089     unsigned ascii_freq = 0;
01090     unsigned bin_freq = 0;
01091     while (n < 7)        bin_freq += s->dyn_ltree[n++].Freq;
01092     while (n < 128)    ascii_freq += s->dyn_ltree[n++].Freq;
01093     while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
01094     s->strm->data_type = bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII;
01095 }

local void tr_static_init (  ) 

Definition at line 235 of file trees.cc.

References _dist_code, _length_code, base_dist, base_length, bi_reverse(), extra_blbits, extra_dbits, extra_lbits, gen_codes(), CLHEP::detail::n, static_bl_desc, static_d_desc, static_dtree, static_l_desc, and static_ltree.

Referenced by _tr_init().

00236 {
00237 #if defined(GEN_TREES_H) || !defined(STDC)
00238     static int static_init_done = 0;
00239     int n;        /* iterates over tree elements */
00240     int bits;     /* bit counter */
00241     int length;   /* length value */
00242     int code;     /* code value */
00243     int dist;     /* distance index */
00244     ush bl_count[MAX_BITS+1];
00245     /* number of codes at each bit length for an optimal tree */
00246 
00247     if (static_init_done) return;
00248 
00249     /* For some embedded targets, global variables are not initialized: */
00250     static_l_desc.static_tree = static_ltree;
00251     static_l_desc.extra_bits = extra_lbits;
00252     static_d_desc.static_tree = static_dtree;
00253     static_d_desc.extra_bits = extra_dbits;
00254     static_bl_desc.extra_bits = extra_blbits;
00255 
00256     /* Initialize the mapping length (0..255) -> length code (0..28) */
00257     length = 0;
00258     for (code = 0; code < LENGTH_CODES-1; code++) {
00259         base_length[code] = length;
00260         for (n = 0; n < (1<<extra_lbits[code]); n++) {
00261             _length_code[length++] = (uch)code;
00262         }
00263     }
00264     Assert (length == 256, (char*)"tr_static_init: length != 256");
00265     /* Note that the length 255 (match length 258) can be represented
00266      * in two different ways: code 284 + 5 bits or code 285, so we
00267      * overwrite length_code[255] to use the best encoding:
00268      */
00269     _length_code[length-1] = (uch)code;
00270 
00271     /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
00272     dist = 0;
00273     for (code = 0 ; code < 16; code++) {
00274         base_dist[code] = dist;
00275         for (n = 0; n < (1<<extra_dbits[code]); n++) {
00276             _dist_code[dist++] = (uch)code;
00277         }
00278     }
00279     Assert (dist == 256, (char*)"tr_static_init: dist != 256");
00280     dist >>= 7; /* from now on, all distances are divided by 128 */
00281     for ( ; code < D_CODES; code++) {
00282         base_dist[code] = dist << 7;
00283         for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
00284             _dist_code[256 + dist++] = (uch)code;
00285         }
00286     }
00287     Assert (dist == 256, (char*)"tr_static_init: 256+dist != 512");
00288 
00289     /* Construct the codes of the static literal tree */
00290     for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
00291     n = 0;
00292     while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
00293     while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
00294     while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
00295     while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
00296     /* Codes 286 and 287 do not exist, but we must include them in the
00297      * tree construction to get a canonical Huffman tree (longest code
00298      * all ones)
00299      */
00300     gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
00301 
00302     /* The static distance tree is trivial: */
00303     for (n = 0; n < D_CODES; n++) {
00304         static_dtree[n].Len = 5;
00305         static_dtree[n].Code = bi_reverse((unsigned)n, 5);
00306     }
00307     static_init_done = 1;
00308 
00309 #  ifdef GEN_TREES_H
00310     gen_trees_header();
00311 #  endif
00312 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
00313 }


Variable Documentation

uch _dist_code[DIST_CODE_LEN]

Definition at line 102 of file trees.cc.

Referenced by tr_static_init().

uch _length_code[MAX_MATCH-MIN_MATCH+1]

Definition at line 108 of file trees.cc.

Referenced by _tr_tally(), compress_block(), and tr_static_init().

local int base_dist[D_CODES]

Definition at line 114 of file trees.cc.

Referenced by compress_block(), and tr_static_init().

local int base_length[LENGTH_CODES]

Definition at line 111 of file trees.cc.

Referenced by compress_block(), and tr_static_init().

local const uch bl_order[BL_CODES] = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}

Definition at line 71 of file trees.cc.

Referenced by build_bl_tree(), and send_all_trees().

local const int extra_blbits[BL_CODES] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}

Definition at line 68 of file trees.cc.

Referenced by tr_static_init().

local const int extra_dbits[D_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}

Definition at line 65 of file trees.cc.

Referenced by _tr_tally(), compress_block(), and tr_static_init().

local const int extra_lbits[LENGTH_CODES] = {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}

Definition at line 62 of file trees.cc.

Referenced by compress_block(), and tr_static_init().

local static_tree_desc static_bl_desc

Initial value:

{(const ct_data *)0, extra_blbits, 0,   BL_CODES, MAX_BL_BITS}

Definition at line 135 of file trees.cc.

Referenced by _tr_init(), and tr_static_init().

local static_tree_desc static_d_desc

Initial value:

{static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS}

Definition at line 132 of file trees.cc.

Referenced by _tr_init(), and tr_static_init().

local ct_data static_dtree[D_CODES]

Definition at line 97 of file trees.cc.

Referenced by _tr_flush_block(), and tr_static_init().

local static_tree_desc static_l_desc

Initial value:

{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}

Definition at line 129 of file trees.cc.

Referenced by _tr_init(), and tr_static_init().

local ct_data static_ltree[L_CODES+2]

Definition at line 90 of file trees.cc.

Referenced by _tr_align(), _tr_flush_block(), gen_codes(), and tr_static_init().


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