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- /*
- * $Id: rawinflate.js,v 0.3 2013/04/09 14:25:38 dankogai Exp dankogai $
- *
- * GNU General Public License, version 2 (GPL-2.0)
- * http://opensource.org/licenses/GPL-2.0
- * original:
- * http://www.onicos.com/staff/iz/amuse/javascript/expert/inflate.txt
- */
-
- (function(ctx){
-
- /* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
- * Version: 1.0.0.1
- * LastModified: Dec 25 1999
- */
-
- /* Interface:
- * data = zip_inflate(src);
- */
-
- /* constant parameters */
- var zip_WSIZE = 32768; // Sliding Window size
- var zip_STORED_BLOCK = 0;
- var zip_STATIC_TREES = 1;
- var zip_DYN_TREES = 2;
-
- /* for inflate */
- var zip_lbits = 9; // bits in base literal/length lookup table
- var zip_dbits = 6; // bits in base distance lookup table
- var zip_INBUFSIZ = 32768; // Input buffer size
- var zip_INBUF_EXTRA = 64; // Extra buffer
-
- /* variables (inflate) */
- var zip_slide;
- var zip_wp; // current position in slide
- var zip_fixed_tl = null; // inflate static
- var zip_fixed_td; // inflate static
- var zip_fixed_bl, zip_fixed_bd; // inflate static
- var zip_bit_buf; // bit buffer
- var zip_bit_len; // bits in bit buffer
- var zip_method;
- var zip_eof;
- var zip_copy_leng;
- var zip_copy_dist;
- var zip_tl, zip_td; // literal/length and distance decoder tables
- var zip_bl, zip_bd; // number of bits decoded by tl and td
-
- var zip_inflate_data;
- var zip_inflate_pos;
-
-
- /* constant tables (inflate) */
- var zip_MASK_BITS = new Array(
- 0x0000,
- 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
- 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff);
- // Tables for deflate from PKZIP's appnote.txt.
- var zip_cplens = new Array( // Copy lengths for literal codes 257..285
- 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
- 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0);
- /* note: see note #13 above about the 258 in this list. */
- var zip_cplext = new Array( // Extra bits for literal codes 257..285
- 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
- 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99); // 99==invalid
- var zip_cpdist = new Array( // Copy offsets for distance codes 0..29
- 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
- 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
- 8193, 12289, 16385, 24577);
- var zip_cpdext = new Array( // Extra bits for distance codes
- 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
- 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
- 12, 12, 13, 13);
- var zip_border = new Array( // Order of the bit length code lengths
- 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15);
- /* objects (inflate) */
-
- var zip_HuftList = function() {
- this.next = null;
- this.list = null;
- }
-
- var zip_HuftNode = function() {
- this.e = 0; // number of extra bits or operation
- this.b = 0; // number of bits in this code or subcode
-
- // union
- this.n = 0; // literal, length base, or distance base
- this.t = null; // (zip_HuftNode) pointer to next level of table
- }
-
- var zip_HuftBuild = function(b, // code lengths in bits (all assumed <= BMAX)
- n, // number of codes (assumed <= N_MAX)
- s, // number of simple-valued codes (0..s-1)
- d, // list of base values for non-simple codes
- e, // list of extra bits for non-simple codes
- mm // maximum lookup bits
- ) {
- this.BMAX = 16; // maximum bit length of any code
- this.N_MAX = 288; // maximum number of codes in any set
- this.status = 0; // 0: success, 1: incomplete table, 2: bad input
- this.root = null; // (zip_HuftList) starting table
- this.m = 0; // maximum lookup bits, returns actual
-
- /* Given a list of code lengths and a maximum table size, make a set of
- tables to decode that set of codes. Return zero on success, one if
- the given code set is incomplete (the tables are still built in this
- case), two if the input is invalid (all zero length codes or an
- oversubscribed set of lengths), and three if not enough memory.
- The code with value 256 is special, and the tables are constructed
- so that no bits beyond that code are fetched when that code is
- decoded. */
- {
- var a; // counter for codes of length k
- var c = new Array(this.BMAX+1); // bit length count table
- var el; // length of EOB code (value 256)
- var f; // i repeats in table every f entries
- var g; // maximum code length
- var h; // table level
- var i; // counter, current code
- var j; // counter
- var k; // number of bits in current code
- var lx = new Array(this.BMAX+1); // stack of bits per table
- var p; // pointer into c[], b[], or v[]
- var pidx; // index of p
- var q; // (zip_HuftNode) points to current table
- var r = new zip_HuftNode(); // table entry for structure assignment
- var u = new Array(this.BMAX); // zip_HuftNode[BMAX][] table stack
- var v = new Array(this.N_MAX); // values in order of bit length
- var w;
- var x = new Array(this.BMAX+1);// bit offsets, then code stack
- var xp; // pointer into x or c
- var y; // number of dummy codes added
- var z; // number of entries in current table
- var o;
- var tail; // (zip_HuftList)
-
- tail = this.root = null;
- for(i = 0; i < c.length; i++)
- c[i] = 0;
- for(i = 0; i < lx.length; i++)
- lx[i] = 0;
- for(i = 0; i < u.length; i++)
- u[i] = null;
- for(i = 0; i < v.length; i++)
- v[i] = 0;
- for(i = 0; i < x.length; i++)
- x[i] = 0;
-
- // Generate counts for each bit length
- el = n > 256 ? b[256] : this.BMAX; // set length of EOB code, if any
- p = b; pidx = 0;
- i = n;
- do {
- c[p[pidx]]++; // assume all entries <= BMAX
- pidx++;
- } while(--i > 0);
- if(c[0] == n) { // null input--all zero length codes
- this.root = null;
- this.m = 0;
- this.status = 0;
- return;
- }
-
- // Find minimum and maximum length, bound *m by those
- for(j = 1; j <= this.BMAX; j++)
- if(c[j] != 0)
- break;
- k = j; // minimum code length
- if(mm < j)
- mm = j;
- for(i = this.BMAX; i != 0; i--)
- if(c[i] != 0)
- break;
- g = i; // maximum code length
- if(mm > i)
- mm = i;
-
- // Adjust last length count to fill out codes, if needed
- for(y = 1 << j; j < i; j++, y <<= 1)
- if((y -= c[j]) < 0) {
- this.status = 2; // bad input: more codes than bits
- this.m = mm;
- return;
- }
- if((y -= c[i]) < 0) {
- this.status = 2;
- this.m = mm;
- return;
- }
- c[i] += y;
-
- // Generate starting offsets into the value table for each length
- x[1] = j = 0;
- p = c;
- pidx = 1;
- xp = 2;
- while(--i > 0) // note that i == g from above
- x[xp++] = (j += p[pidx++]);
-
- // Make a table of values in order of bit lengths
- p = b; pidx = 0;
- i = 0;
- do {
- if((j = p[pidx++]) != 0)
- v[x[j]++] = i;
- } while(++i < n);
- n = x[g]; // set n to length of v
-
- // Generate the Huffman codes and for each, make the table entries
- x[0] = i = 0; // first Huffman code is zero
- p = v; pidx = 0; // grab values in bit order
- h = -1; // no tables yet--level -1
- w = lx[0] = 0; // no bits decoded yet
- q = null; // ditto
- z = 0; // ditto
-
- // go through the bit lengths (k already is bits in shortest code)
- for(; k <= g; k++) {
- a = c[k];
- while(a-- > 0) {
- // here i is the Huffman code of length k bits for value p[pidx]
- // make tables up to required level
- while(k > w + lx[1 + h]) {
- w += lx[1 + h]; // add bits already decoded
- h++;
-
- // compute minimum size table less than or equal to *m bits
- z = (z = g - w) > mm ? mm : z; // upper limit
- if((f = 1 << (j = k - w)) > a + 1) { // try a k-w bit table
- // too few codes for k-w bit table
- f -= a + 1; // deduct codes from patterns left
- xp = k;
- while(++j < z) { // try smaller tables up to z bits
- if((f <<= 1) <= c[++xp])
- break; // enough codes to use up j bits
- f -= c[xp]; // else deduct codes from patterns
- }
- }
- if(w + j > el && w < el)
- j = el - w; // make EOB code end at table
- z = 1 << j; // table entries for j-bit table
- lx[1 + h] = j; // set table size in stack
-
- // allocate and link in new table
- q = new Array(z);
- for(o = 0; o < z; o++) {
- q[o] = new zip_HuftNode();
- }
-
- if(tail == null)
- tail = this.root = new zip_HuftList();
- else
- tail = tail.next = new zip_HuftList();
- tail.next = null;
- tail.list = q;
- u[h] = q; // table starts after link
-
- /* connect to last table, if there is one */
- if(h > 0) {
- x[h] = i; // save pattern for backing up
- r.b = lx[h]; // bits to dump before this table
- r.e = 16 + j; // bits in this table
- r.t = q; // pointer to this table
- j = (i & ((1 << w) - 1)) >> (w - lx[h]);
- u[h-1][j].e = r.e;
- u[h-1][j].b = r.b;
- u[h-1][j].n = r.n;
- u[h-1][j].t = r.t;
- }
- }
-
- // set up table entry in r
- r.b = k - w;
- if(pidx >= n)
- r.e = 99; // out of values--invalid code
- else if(p[pidx] < s) {
- r.e = (p[pidx] < 256 ? 16 : 15); // 256 is end-of-block code
- r.n = p[pidx++]; // simple code is just the value
- } else {
- r.e = e[p[pidx] - s]; // non-simple--look up in lists
- r.n = d[p[pidx++] - s];
- }
-
- // fill code-like entries with r //
- f = 1 << (k - w);
- for(j = i >> w; j < z; j += f) {
- q[j].e = r.e;
- q[j].b = r.b;
- q[j].n = r.n;
- q[j].t = r.t;
- }
-
- // backwards increment the k-bit code i
- for(j = 1 << (k - 1); (i & j) != 0; j >>= 1)
- i ^= j;
- i ^= j;
-
- // backup over finished tables
- while((i & ((1 << w) - 1)) != x[h]) {
- w -= lx[h]; // don't need to update q
- h--;
- }
- }
- }
-
- /* return actual size of base table */
- this.m = lx[1];
-
- /* Return true (1) if we were given an incomplete table */
- this.status = ((y != 0 && g != 1) ? 1 : 0);
- } /* end of constructor */
- }
-
-
- /* routines (inflate) */
-
- var zip_GET_BYTE = function() {
- if(zip_inflate_data.length == zip_inflate_pos)
- return -1;
- return zip_inflate_data.charCodeAt(zip_inflate_pos++) & 0xff;
- }
-
- var zip_NEEDBITS = function(n) {
- while(zip_bit_len < n) {
- zip_bit_buf |= zip_GET_BYTE() << zip_bit_len;
- zip_bit_len += 8;
- }
- }
-
- var zip_GETBITS = function(n) {
- return zip_bit_buf & zip_MASK_BITS[n];
- }
-
- var zip_DUMPBITS = function(n) {
- zip_bit_buf >>= n;
- zip_bit_len -= n;
- }
-
- var zip_inflate_codes = function(buff, off, size) {
- /* inflate (decompress) the codes in a deflated (compressed) block.
- Return an error code or zero if it all goes ok. */
- var e; // table entry flag/number of extra bits
- var t; // (zip_HuftNode) pointer to table entry
- var n;
-
- if(size == 0)
- return 0;
-
- // inflate the coded data
- n = 0;
- for(;;) { // do until end of block
- zip_NEEDBITS(zip_bl);
- t = zip_tl.list[zip_GETBITS(zip_bl)];
- e = t.e;
- while(e > 16) {
- if(e == 99)
- return -1;
- zip_DUMPBITS(t.b);
- e -= 16;
- zip_NEEDBITS(e);
- t = t.t[zip_GETBITS(e)];
- e = t.e;
- }
- zip_DUMPBITS(t.b);
-
- if(e == 16) { // then it's a literal
- zip_wp &= zip_WSIZE - 1;
- buff[off + n++] = zip_slide[zip_wp++] = t.n;
- if(n == size)
- return size;
- continue;
- }
-
- // exit if end of block
- if(e == 15)
- break;
-
- // it's an EOB or a length
-
- // get length of block to copy
- zip_NEEDBITS(e);
- zip_copy_leng = t.n + zip_GETBITS(e);
- zip_DUMPBITS(e);
-
- // decode distance of block to copy
- zip_NEEDBITS(zip_bd);
- t = zip_td.list[zip_GETBITS(zip_bd)];
- e = t.e;
-
- while(e > 16) {
- if(e == 99)
- return -1;
- zip_DUMPBITS(t.b);
- e -= 16;
- zip_NEEDBITS(e);
- t = t.t[zip_GETBITS(e)];
- e = t.e;
- }
- zip_DUMPBITS(t.b);
- zip_NEEDBITS(e);
- zip_copy_dist = zip_wp - t.n - zip_GETBITS(e);
- zip_DUMPBITS(e);
-
- // do the copy
- while(zip_copy_leng > 0 && n < size) {
- zip_copy_leng--;
- zip_copy_dist &= zip_WSIZE - 1;
- zip_wp &= zip_WSIZE - 1;
- buff[off + n++] = zip_slide[zip_wp++]
- = zip_slide[zip_copy_dist++];
- }
-
- if(n == size)
- return size;
- }
-
- zip_method = -1; // done
- return n;
- }
-
- var zip_inflate_stored = function(buff, off, size) {
- /* "decompress" an inflated type 0 (stored) block. */
- var n;
-
- // go to byte boundary
- n = zip_bit_len & 7;
- zip_DUMPBITS(n);
-
- // get the length and its complement
- zip_NEEDBITS(16);
- n = zip_GETBITS(16);
- zip_DUMPBITS(16);
- zip_NEEDBITS(16);
- if(n != ((~zip_bit_buf) & 0xffff))
- return -1; // error in compressed data
- zip_DUMPBITS(16);
-
- // read and output the compressed data
- zip_copy_leng = n;
-
- n = 0;
- while(zip_copy_leng > 0 && n < size) {
- zip_copy_leng--;
- zip_wp &= zip_WSIZE - 1;
- zip_NEEDBITS(8);
- buff[off + n++] = zip_slide[zip_wp++] =
- zip_GETBITS(8);
- zip_DUMPBITS(8);
- }
-
- if(zip_copy_leng == 0)
- zip_method = -1; // done
- return n;
- }
-
- var zip_inflate_fixed = function(buff, off, size) {
- /* decompress an inflated type 1 (fixed Huffman codes) block. We should
- either replace this with a custom decoder, or at least precompute the
- Huffman tables. */
-
- // if first time, set up tables for fixed blocks
- if(zip_fixed_tl == null) {
- var i; // temporary variable
- var l = new Array(288); // length list for huft_build
- var h; // zip_HuftBuild
-
- // literal table
- for(i = 0; i < 144; i++)
- l[i] = 8;
- for(; i < 256; i++)
- l[i] = 9;
- for(; i < 280; i++)
- l[i] = 7;
- for(; i < 288; i++) // make a complete, but wrong code set
- l[i] = 8;
- zip_fixed_bl = 7;
-
- h = new zip_HuftBuild(l, 288, 257, zip_cplens, zip_cplext,
- zip_fixed_bl);
- if(h.status != 0) {
- alert("HufBuild error: "+h.status);
- return -1;
- }
- zip_fixed_tl = h.root;
- zip_fixed_bl = h.m;
-
- // distance table
- for(i = 0; i < 30; i++) // make an incomplete code set
- l[i] = 5;
- zip_fixed_bd = 5;
-
- h = new zip_HuftBuild(l, 30, 0, zip_cpdist, zip_cpdext, zip_fixed_bd);
- if(h.status > 1) {
- zip_fixed_tl = null;
- alert("HufBuild error: "+h.status);
- return -1;
- }
- zip_fixed_td = h.root;
- zip_fixed_bd = h.m;
- }
-
- zip_tl = zip_fixed_tl;
- zip_td = zip_fixed_td;
- zip_bl = zip_fixed_bl;
- zip_bd = zip_fixed_bd;
- return zip_inflate_codes(buff, off, size);
- }
-
- var zip_inflate_dynamic = function(buff, off, size) {
- // decompress an inflated type 2 (dynamic Huffman codes) block.
- var i; // temporary variables
- var j;
- var l; // last length
- var n; // number of lengths to get
- var t; // (zip_HuftNode) literal/length code table
- var nb; // number of bit length codes
- var nl; // number of literal/length codes
- var nd; // number of distance codes
- var ll = new Array(286+30); // literal/length and distance code lengths
- var h; // (zip_HuftBuild)
-
- for(i = 0; i < ll.length; i++)
- ll[i] = 0;
-
- // read in table lengths
- zip_NEEDBITS(5);
- nl = 257 + zip_GETBITS(5); // number of literal/length codes
- zip_DUMPBITS(5);
- zip_NEEDBITS(5);
- nd = 1 + zip_GETBITS(5); // number of distance codes
- zip_DUMPBITS(5);
- zip_NEEDBITS(4);
- nb = 4 + zip_GETBITS(4); // number of bit length codes
- zip_DUMPBITS(4);
- if(nl > 286 || nd > 30)
- return -1; // bad lengths
-
- // read in bit-length-code lengths
- for(j = 0; j < nb; j++)
- {
- zip_NEEDBITS(3);
- ll[zip_border[j]] = zip_GETBITS(3);
- zip_DUMPBITS(3);
- }
- for(; j < 19; j++)
- ll[zip_border[j]] = 0;
-
- // build decoding table for trees--single level, 7 bit lookup
- zip_bl = 7;
- h = new zip_HuftBuild(ll, 19, 19, null, null, zip_bl);
- if(h.status != 0)
- return -1; // incomplete code set
-
- zip_tl = h.root;
- zip_bl = h.m;
-
- // read in literal and distance code lengths
- n = nl + nd;
- i = l = 0;
- while(i < n) {
- zip_NEEDBITS(zip_bl);
- t = zip_tl.list[zip_GETBITS(zip_bl)];
- j = t.b;
- zip_DUMPBITS(j);
- j = t.n;
- if(j < 16) // length of code in bits (0..15)
- ll[i++] = l = j; // save last length in l
- else if(j == 16) { // repeat last length 3 to 6 times
- zip_NEEDBITS(2);
- j = 3 + zip_GETBITS(2);
- zip_DUMPBITS(2);
- if(i + j > n)
- return -1;
- while(j-- > 0)
- ll[i++] = l;
- } else if(j == 17) { // 3 to 10 zero length codes
- zip_NEEDBITS(3);
- j = 3 + zip_GETBITS(3);
- zip_DUMPBITS(3);
- if(i + j > n)
- return -1;
- while(j-- > 0)
- ll[i++] = 0;
- l = 0;
- } else { // j == 18: 11 to 138 zero length codes
- zip_NEEDBITS(7);
- j = 11 + zip_GETBITS(7);
- zip_DUMPBITS(7);
- if(i + j > n)
- return -1;
- while(j-- > 0)
- ll[i++] = 0;
- l = 0;
- }
- }
-
- // build the decoding tables for literal/length and distance codes
- zip_bl = zip_lbits;
- h = new zip_HuftBuild(ll, nl, 257, zip_cplens, zip_cplext, zip_bl);
- if(zip_bl == 0) // no literals or lengths
- h.status = 1;
- if(h.status != 0) {
- if(h.status == 1)
- ;// **incomplete literal tree**
- return -1; // incomplete code set
- }
- zip_tl = h.root;
- zip_bl = h.m;
-
- for(i = 0; i < nd; i++)
- ll[i] = ll[i + nl];
- zip_bd = zip_dbits;
- h = new zip_HuftBuild(ll, nd, 0, zip_cpdist, zip_cpdext, zip_bd);
- zip_td = h.root;
- zip_bd = h.m;
-
- if(zip_bd == 0 && nl > 257) { // lengths but no distances
- // **incomplete distance tree**
- return -1;
- }
-
- if(h.status == 1) {
- ;// **incomplete distance tree**
- }
- if(h.status != 0)
- return -1;
-
- // decompress until an end-of-block code
- return zip_inflate_codes(buff, off, size);
- }
-
- var zip_inflate_start = function() {
- var i;
-
- if(zip_slide == null)
- zip_slide = new Array(2 * zip_WSIZE);
- zip_wp = 0;
- zip_bit_buf = 0;
- zip_bit_len = 0;
- zip_method = -1;
- zip_eof = false;
- zip_copy_leng = zip_copy_dist = 0;
- zip_tl = null;
- }
-
- var zip_inflate_internal = function(buff, off, size) {
- // decompress an inflated entry
- var n, i;
-
- n = 0;
- while(n < size) {
- if(zip_eof && zip_method == -1)
- return n;
-
- if(zip_copy_leng > 0) {
- if(zip_method != zip_STORED_BLOCK) {
- // STATIC_TREES or DYN_TREES
- while(zip_copy_leng > 0 && n < size) {
- zip_copy_leng--;
- zip_copy_dist &= zip_WSIZE - 1;
- zip_wp &= zip_WSIZE - 1;
- buff[off + n++] = zip_slide[zip_wp++] =
- zip_slide[zip_copy_dist++];
- }
- } else {
- while(zip_copy_leng > 0 && n < size) {
- zip_copy_leng--;
- zip_wp &= zip_WSIZE - 1;
- zip_NEEDBITS(8);
- buff[off + n++] = zip_slide[zip_wp++] = zip_GETBITS(8);
- zip_DUMPBITS(8);
- }
- if(zip_copy_leng == 0)
- zip_method = -1; // done
- }
- if(n == size)
- return n;
- }
-
- if(zip_method == -1) {
- if(zip_eof)
- break;
-
- // read in last block bit
- zip_NEEDBITS(1);
- if(zip_GETBITS(1) != 0)
- zip_eof = true;
- zip_DUMPBITS(1);
-
- // read in block type
- zip_NEEDBITS(2);
- zip_method = zip_GETBITS(2);
- zip_DUMPBITS(2);
- zip_tl = null;
- zip_copy_leng = 0;
- }
-
- switch(zip_method) {
- case 0: // zip_STORED_BLOCK
- i = zip_inflate_stored(buff, off + n, size - n);
- break;
-
- case 1: // zip_STATIC_TREES
- if(zip_tl != null)
- i = zip_inflate_codes(buff, off + n, size - n);
- else
- i = zip_inflate_fixed(buff, off + n, size - n);
- break;
-
- case 2: // zip_DYN_TREES
- if(zip_tl != null)
- i = zip_inflate_codes(buff, off + n, size - n);
- else
- i = zip_inflate_dynamic(buff, off + n, size - n);
- break;
-
- default: // error
- i = -1;
- break;
- }
-
- if(i == -1) {
- if(zip_eof)
- return 0;
- return -1;
- }
- n += i;
- }
- return n;
- }
-
- var zip_inflate = function(str) {
- var i, j;
-
- zip_inflate_start();
- zip_inflate_data = str;
- zip_inflate_pos = 0;
-
- var buff = new Array(1024);
- var aout = [];
- while((i = zip_inflate_internal(buff, 0, buff.length)) > 0) {
- var cbuf = new Array(i);
- for(j = 0; j < i; j++){
- cbuf[j] = String.fromCharCode(buff[j]);
- }
- aout[aout.length] = cbuf.join("");
- }
- zip_inflate_data = null; // G.C.
- return aout.join("");
- }
-
- if (! ctx.RawDeflate) ctx.RawDeflate = {};
- ctx.RawDeflate.inflate = zip_inflate;
-
- })(this);
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