Index: third_party/bzip2/huffman.c |
=================================================================== |
--- third_party/bzip2/huffman.c (revision 199288) |
+++ third_party/bzip2/huffman.c (working copy) |
@@ -1,205 +0,0 @@ |
- |
-/*-------------------------------------------------------------*/ |
-/*--- Huffman coding low-level stuff ---*/ |
-/*--- huffman.c ---*/ |
-/*-------------------------------------------------------------*/ |
- |
-/* ------------------------------------------------------------------ |
- This file is part of bzip2/libbzip2, a program and library for |
- lossless, block-sorting data compression. |
- |
- bzip2/libbzip2 version 1.0.6 of 6 September 2010 |
- Copyright (C) 1996-2010 Julian Seward <jseward@bzip.org> |
- |
- Please read the WARNING, DISCLAIMER and PATENTS sections in the |
- README file. |
- |
- This program is released under the terms of the license contained |
- in the file LICENSE. |
- ------------------------------------------------------------------ */ |
- |
- |
-#include "bzlib_private.h" |
- |
-/*---------------------------------------------------*/ |
-#define WEIGHTOF(zz0) ((zz0) & 0xffffff00) |
-#define DEPTHOF(zz1) ((zz1) & 0x000000ff) |
-#define MYMAX(zz2,zz3) ((zz2) > (zz3) ? (zz2) : (zz3)) |
- |
-#define ADDWEIGHTS(zw1,zw2) \ |
- (WEIGHTOF(zw1)+WEIGHTOF(zw2)) | \ |
- (1 + MYMAX(DEPTHOF(zw1),DEPTHOF(zw2))) |
- |
-#define UPHEAP(z) \ |
-{ \ |
- Int32 zz, tmp; \ |
- zz = z; tmp = heap[zz]; \ |
- while (weight[tmp] < weight[heap[zz >> 1]]) { \ |
- heap[zz] = heap[zz >> 1]; \ |
- zz >>= 1; \ |
- } \ |
- heap[zz] = tmp; \ |
-} |
- |
-#define DOWNHEAP(z) \ |
-{ \ |
- Int32 zz, yy, tmp; \ |
- zz = z; tmp = heap[zz]; \ |
- while (True) { \ |
- yy = zz << 1; \ |
- if (yy > nHeap) break; \ |
- if (yy < nHeap && \ |
- weight[heap[yy+1]] < weight[heap[yy]]) \ |
- yy++; \ |
- if (weight[tmp] < weight[heap[yy]]) break; \ |
- heap[zz] = heap[yy]; \ |
- zz = yy; \ |
- } \ |
- heap[zz] = tmp; \ |
-} |
- |
- |
-/*---------------------------------------------------*/ |
-void BZ2_hbMakeCodeLengths ( UChar *len, |
- Int32 *freq, |
- Int32 alphaSize, |
- Int32 maxLen ) |
-{ |
- /*-- |
- Nodes and heap entries run from 1. Entry 0 |
- for both the heap and nodes is a sentinel. |
- --*/ |
- Int32 nNodes, nHeap, n1, n2, i, j, k; |
- Bool tooLong; |
- |
- Int32 heap [ BZ_MAX_ALPHA_SIZE + 2 ]; |
- Int32 weight [ BZ_MAX_ALPHA_SIZE * 2 ]; |
- Int32 parent [ BZ_MAX_ALPHA_SIZE * 2 ]; |
- |
- for (i = 0; i < alphaSize; i++) |
- weight[i+1] = (freq[i] == 0 ? 1 : freq[i]) << 8; |
- |
- while (True) { |
- |
- nNodes = alphaSize; |
- nHeap = 0; |
- |
- heap[0] = 0; |
- weight[0] = 0; |
- parent[0] = -2; |
- |
- for (i = 1; i <= alphaSize; i++) { |
- parent[i] = -1; |
- nHeap++; |
- heap[nHeap] = i; |
- UPHEAP(nHeap); |
- } |
- |
- AssertH( nHeap < (BZ_MAX_ALPHA_SIZE+2), 2001 ); |
- |
- while (nHeap > 1) { |
- n1 = heap[1]; heap[1] = heap[nHeap]; nHeap--; DOWNHEAP(1); |
- n2 = heap[1]; heap[1] = heap[nHeap]; nHeap--; DOWNHEAP(1); |
- nNodes++; |
- parent[n1] = parent[n2] = nNodes; |
- weight[nNodes] = ADDWEIGHTS(weight[n1], weight[n2]); |
- parent[nNodes] = -1; |
- nHeap++; |
- heap[nHeap] = nNodes; |
- UPHEAP(nHeap); |
- } |
- |
- AssertH( nNodes < (BZ_MAX_ALPHA_SIZE * 2), 2002 ); |
- |
- tooLong = False; |
- for (i = 1; i <= alphaSize; i++) { |
- j = 0; |
- k = i; |
- while (parent[k] >= 0) { k = parent[k]; j++; } |
- len[i-1] = j; |
- if (j > maxLen) tooLong = True; |
- } |
- |
- if (! tooLong) break; |
- |
- /* 17 Oct 04: keep-going condition for the following loop used |
- to be 'i < alphaSize', which missed the last element, |
- theoretically leading to the possibility of the compressor |
- looping. However, this count-scaling step is only needed if |
- one of the generated Huffman code words is longer than |
- maxLen, which up to and including version 1.0.2 was 20 bits, |
- which is extremely unlikely. In version 1.0.3 maxLen was |
- changed to 17 bits, which has minimal effect on compression |
- ratio, but does mean this scaling step is used from time to |
- time, enough to verify that it works. |
- |
- This means that bzip2-1.0.3 and later will only produce |
- Huffman codes with a maximum length of 17 bits. However, in |
- order to preserve backwards compatibility with bitstreams |
- produced by versions pre-1.0.3, the decompressor must still |
- handle lengths of up to 20. */ |
- |
- for (i = 1; i <= alphaSize; i++) { |
- j = weight[i] >> 8; |
- j = 1 + (j / 2); |
- weight[i] = j << 8; |
- } |
- } |
-} |
- |
- |
-/*---------------------------------------------------*/ |
-void BZ2_hbAssignCodes ( Int32 *code, |
- UChar *length, |
- Int32 minLen, |
- Int32 maxLen, |
- Int32 alphaSize ) |
-{ |
- Int32 n, vec, i; |
- |
- vec = 0; |
- for (n = minLen; n <= maxLen; n++) { |
- for (i = 0; i < alphaSize; i++) |
- if (length[i] == n) { code[i] = vec; vec++; }; |
- vec <<= 1; |
- } |
-} |
- |
- |
-/*---------------------------------------------------*/ |
-void BZ2_hbCreateDecodeTables ( Int32 *limit, |
- Int32 *base, |
- Int32 *perm, |
- UChar *length, |
- Int32 minLen, |
- Int32 maxLen, |
- Int32 alphaSize ) |
-{ |
- Int32 pp, i, j, vec; |
- |
- pp = 0; |
- for (i = minLen; i <= maxLen; i++) |
- for (j = 0; j < alphaSize; j++) |
- if (length[j] == i) { perm[pp] = j; pp++; }; |
- |
- for (i = 0; i < BZ_MAX_CODE_LEN; i++) base[i] = 0; |
- for (i = 0; i < alphaSize; i++) base[length[i]+1]++; |
- |
- for (i = 1; i < BZ_MAX_CODE_LEN; i++) base[i] += base[i-1]; |
- |
- for (i = 0; i < BZ_MAX_CODE_LEN; i++) limit[i] = 0; |
- vec = 0; |
- |
- for (i = minLen; i <= maxLen; i++) { |
- vec += (base[i+1] - base[i]); |
- limit[i] = vec-1; |
- vec <<= 1; |
- } |
- for (i = minLen + 1; i <= maxLen; i++) |
- base[i] = ((limit[i-1] + 1) << 1) - base[i]; |
-} |
- |
- |
-/*-------------------------------------------------------------*/ |
-/*--- end huffman.c ---*/ |
-/*-------------------------------------------------------------*/ |