public static URShift ( int number, int bits ) : int | ||
number | int | Number to operate on |
bits | int | Ammount of bits to shift |
Результат | int |
// Reverse the first len bits of a code, using straightforward code (a faster // method would use a table) // IN assertion: 1 <= len <= 15 internal static int bi_reverse(int code, int len) { int res = 0; do { res |= code & 1; code = SupportClass.URShift(code, 1); res <<= 1; }while (--len > 0); return(SupportClass.URShift(res, 1)); }
internal int[] x = null; // bit offsets, then code stack private int huft_build(int[] b, int bindex, int n, int s, int[] d, int[] e, int[] t, int[] m, int[] hp, int[] hn, int[] v) { // Given a list of code lengths and a maximum table size, make a set of // tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR // if the given code set is incomplete (the tables are still built in this // case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of // lengths), or Z_MEM_ERROR if not enough memory. int a; // counter for codes of length k int f; // i repeats in table every f entries int g; // maximum code length int h; // table level int i; // counter, current code int j; // counter int k; // number of bits in current code int l; // bits per table (returned in m) int mask; // (1 << w) - 1, to avoid cc -O bug on HP int p; // pointer into c[], b[], or v[] int q; // points to current table int w; // bits before this table == (l * h) int xp; // pointer into x int y; // number of dummy codes added int z; // number of entries in current table // Generate counts for each bit length p = 0; i = n; do { c[b[bindex + p]]++; p++; i--; // assume all entries <= BMAX }while (i != 0); if (c[0] == n) { // null input--all zero length codes t[0] = -1; m[0] = 0; return(Z_OK); } // Find minimum and maximum length, bound *m by those l = m[0]; for (j = 1; j <= BMAX; j++) { if (c[j] != 0) { break; } } k = j; // minimum code length if (l < j) { l = j; } for (i = BMAX; i != 0; i--) { if (c[i] != 0) { break; } } g = i; // maximum code length if (l > i) { l = i; } m[0] = l; // Adjust last length count to fill out codes, if needed for (y = 1 << j; j < i; j++, y <<= 1) { if ((y -= c[j]) < 0) { return(Z_DATA_ERROR); } } if ((y -= c[i]) < 0) { return(Z_DATA_ERROR); } c[i] += y; // Generate starting offsets into the value table for each length x[1] = j = 0; p = 1; xp = 2; while (--i != 0) { // note that i == g from above x[xp] = (j += c[p]); xp++; p++; } // Make a table of values in order of bit lengths i = 0; p = 0; do { if ((j = b[bindex + p]) != 0) { v[x[j]++] = i; } p++; }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 = 0; // grab values in bit order h = -1; // no tables yet--level -1 w = -l; // bits decoded == (l * h) u[0] = 0; // just to keep compilers happy q = 0; // 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 // make tables up to required level while (k > w + l) { h++; w += l; // previous table always l bits // compute minimum size table less than or equal to l bits z = g - w; z = (z > l)?l:z; // table size 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; if (j < z) { 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 } } } z = 1 << j; // table entries for j-bit table // allocate new table if (hn[0] + z > MANY) { // (note: doesn't matter for fixed) return(Z_DATA_ERROR); // overflow of MANY } u[h] = q = hn[0]; // DEBUG hn[0] += z; // connect to last table, if there is one if (h != 0) { x[h] = i; // save pattern for backing up r[0] = (byte)j; // bits in this table r[1] = (byte)l; // bits to dump before this table j = SupportClass.URShift(i, (w - l)); r[2] = (int)(q - u[h - 1] - j); // offset to this table Array.Copy(r, 0, hp, (u[h - 1] + j) * 3, 3); // connect to last table } else { t[0] = q; // first table is returned result } } // set up table entry in r r[1] = (byte)(k - w); if (p >= n) { r[0] = 128 + 64; // out of values--invalid code } else if (v[p] < s) { r[0] = (byte)(v[p] < 256?0:32 + 64); // 256 is end-of-block r[2] = v[p++]; // simple code is just the value } else { r[0] = (byte)(e[v[p] - s] + 16 + 64); // non-simple--look up in lists r[2] = d[v[p++] - s]; } // fill code-like entries with r f = 1 << (k - w); for (j = SupportClass.URShift(i, w); j < z; j += f) { Array.Copy(r, 0, hp, (q + j) * 3, 3); } // backwards increment the k-bit code i for (j = 1 << (k - 1); (i & j) != 0; j = SupportClass.URShift(j, 1)) { i ^= j; } i ^= j; // backup over finished tables mask = (1 << w) - 1; // needed on HP, cc -O bug while ((i & mask) != x[h]) { h--; // don't need to update q w -= l; mask = (1 << w) - 1; } } } // Return Z_BUF_ERROR if we were given an incomplete table return(y != 0 && g != 1?Z_BUF_ERROR:Z_OK); }
internal int proc(InfBlocks s, ZStream z, int r) { int j; // temporary storage //int[] t; // temporary pointer int tindex; // temporary pointer int e; // extra bits or operation int b = 0; // bit buffer int k = 0; // bits in bit buffer int p = 0; // input data pointer int n; // bytes available there int q; // output window write pointer int m; // bytes to end of window or read pointer int f; // pointer to copy strings from // copy input/output information to locals (UPDATE macro restores) p = z.next_in_index; n = z.avail_in; b = s.bitb; k = s.bitk; q = s.write; m = q < s.read?s.read - q - 1:s.end - q; // process input and output based on current state while (true) { switch (mode) { // waiting for "i:"=input, "o:"=output, "x:"=nothing case START: // x: set up for LEN if (m >= 258 && n >= 10) { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; r = inflate_fast(lbits, dbits, ltree, ltree_index, dtree, dtree_index, s, z); p = z.next_in_index; n = z.avail_in; b = s.bitb; k = s.bitk; q = s.write; m = q < s.read?s.read - q - 1:s.end - q; if (r != Z_OK) { mode = r == Z_STREAM_END?WASH:BADCODE; break; } } need = lbits; tree = ltree; tree_index = ltree_index; mode = LEN; goto case LEN; case LEN: // i: get length/literal/eob next j = need; while (k < (j)) { if (n != 0) { r = Z_OK; } else { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } tindex = (tree_index + (b & inflate_mask[j])) * 3; b = SupportClass.URShift(b, (tree[tindex + 1])); k -= (tree[tindex + 1]); e = tree[tindex]; if (e == 0) { // literal lit = tree[tindex + 2]; mode = LIT; break; } if ((e & 16) != 0) { // length get_Renamed = e & 15; len = tree[tindex + 2]; mode = LENEXT; break; } if ((e & 64) == 0) { // next table need = e; tree_index = tindex / 3 + tree[tindex + 2]; break; } if ((e & 32) != 0) { // end of block mode = WASH; break; } mode = BADCODE; // invalid code z.msg = "invalid literal/length code"; r = Z_DATA_ERROR; s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); case LENEXT: // i: getting length extra (have base) j = get_Renamed; while (k < (j)) { if (n != 0) { r = Z_OK; } else { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } len += (b & inflate_mask[j]); b >>= j; k -= j; need = dbits; tree = dtree; tree_index = dtree_index; mode = DIST; goto case DIST; case DIST: // i: get distance next j = need; while (k < (j)) { if (n != 0) { r = Z_OK; } else { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } tindex = (tree_index + (b & inflate_mask[j])) * 3; b >>= tree[tindex + 1]; k -= tree[tindex + 1]; e = (tree[tindex]); if ((e & 16) != 0) { // distance get_Renamed = e & 15; dist = tree[tindex + 2]; mode = DISTEXT; break; } if ((e & 64) == 0) { // next table need = e; tree_index = tindex / 3 + tree[tindex + 2]; break; } mode = BADCODE; // invalid code z.msg = "invalid distance code"; r = Z_DATA_ERROR; s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); case DISTEXT: // i: getting distance extra j = get_Renamed; while (k < (j)) { if (n != 0) { r = Z_OK; } else { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } dist += (b & inflate_mask[j]); b >>= j; k -= j; mode = COPY; goto case COPY; case COPY: // o: copying bytes in window, waiting for space f = q - dist; while (f < 0) { // modulo window size-"while" instead f += s.end; // of "if" handles invalid distances } while (len != 0) { if (m == 0) { if (q == s.end && s.read != 0) { q = 0; m = q < s.read?s.read - q - 1:s.end - q; } if (m == 0) { s.write = q; r = s.inflate_flush(z, r); q = s.write; m = q < s.read?s.read - q - 1:s.end - q; if (q == s.end && s.read != 0) { q = 0; m = q < s.read?s.read - q - 1:s.end - q; } if (m == 0) { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } } } s.window[q++] = s.window[f++]; m--; if (f == s.end) { f = 0; } len--; } mode = START; break; case LIT: // o: got literal, waiting for output space if (m == 0) { if (q == s.end && s.read != 0) { q = 0; m = q < s.read?s.read - q - 1:s.end - q; } if (m == 0) { s.write = q; r = s.inflate_flush(z, r); q = s.write; m = q < s.read?s.read - q - 1:s.end - q; if (q == s.end && s.read != 0) { q = 0; m = q < s.read?s.read - q - 1:s.end - q; } if (m == 0) { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } } } r = Z_OK; s.window[q++] = (byte)lit; m--; mode = START; break; case WASH: // o: got eob, possibly more output if (k > 7) { // return unused byte, if any k -= 8; n++; p--; // can always return one } s.write = q; r = s.inflate_flush(z, r); q = s.write; m = q < s.read?s.read - q - 1:s.end - q; if (s.read != s.write) { s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } mode = END; goto case END; case END: r = Z_STREAM_END; s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); case BADCODE: // x: got error r = Z_DATA_ERROR; s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); default: r = Z_STREAM_ERROR; s.bitb = b; s.bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; s.write = q; return(s.inflate_flush(z, r)); } } }
internal int proc(ZStream z, int r) { int t; // temporary storage int b; // bit buffer int k; // bits in bit buffer int p; // input data pointer int n; // bytes available there int q; // output window write pointer int m; // bytes to end of window or read pointer // copy input/output information to locals (UPDATE macro restores) { p = z.next_in_index; n = z.avail_in; b = bitb; k = bitk; } { q = write; m = (int)(q < read?read - q - 1:end - q); } // process input based on current state while (true) { switch (mode) { case TYPE: while (k < (3)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } t = (int)(b & 7); last = t & 1; switch (SupportClass.URShift(t, 1)) { case 0: // stored { b = SupportClass.URShift(b, (3)); k -= (3); } t = k & 7; // go to byte boundary { b = SupportClass.URShift(b, (t)); k -= (t); } mode = LENS; // get length of stored block break; case 1: // fixed { int[] bl = new int[1]; int[] bd = new int[1]; int[][] tl = new int[1][]; int[][] td = new int[1][]; InfTree.inflate_trees_fixed(bl, bd, tl, td, z); codes.init(bl[0], bd[0], tl[0], 0, td[0], 0, z); } { b = SupportClass.URShift(b, (3)); k -= (3); } mode = CODES; break; case 2: // dynamic { b = SupportClass.URShift(b, (3)); k -= (3); } mode = TABLE; break; case 3: // illegal { b = SupportClass.URShift(b, (3)); k -= (3); } mode = BAD; z.msg = "invalid block type"; r = Z_DATA_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } break; case LENS: while (k < (32)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } if (((SupportClass.URShift((~b), 16)) & 0xffff) != (b & 0xffff)) { mode = BAD; z.msg = "invalid stored block lengths"; r = Z_DATA_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } left = (b & 0xffff); b = k = 0; // dump bits mode = left != 0?STORED:(last != 0?DRY:TYPE); break; case STORED: if (n == 0) { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } if (m == 0) { if (q == end && read != 0) { q = 0; m = (int)(q < read?read - q - 1:end - q); } if (m == 0) { write = q; r = inflate_flush(z, r); q = write; m = (int)(q < read?read - q - 1:end - q); if (q == end && read != 0) { q = 0; m = (int)(q < read?read - q - 1:end - q); } if (m == 0) { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } } } r = Z_OK; t = left; if (t > n) { t = n; } if (t > m) { t = m; } Array.Copy(z.next_in, p, window, q, t); p += t; n -= t; q += t; m -= t; if ((left -= t) != 0) { break; } mode = last != 0?DRY:TYPE; break; case TABLE: while (k < (14)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } table = t = (b & 0x3fff); if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) { mode = BAD; z.msg = "too many length or distance symbols"; r = Z_DATA_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); if (blens == null || blens.Length < t) { blens = new int[t]; } else { for (int i = 0; i < t; i++) { blens[i] = 0; } } { b = SupportClass.URShift(b, (14)); k -= (14); } index = 0; mode = BTREE; goto case BTREE; case BTREE: while (index < 4 + (SupportClass.URShift(table, 10))) { while (k < (3)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } blens[border[index++]] = b & 7; { b = SupportClass.URShift(b, (3)); k -= (3); } } while (index < 19) { blens[border[index++]] = 0; } bb[0] = 7; t = inftree.inflate_trees_bits(blens, bb, tb, hufts, z); if (t != Z_OK) { r = t; if (r == Z_DATA_ERROR) { blens = null; mode = BAD; } bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } index = 0; mode = DTREE; goto case DTREE; case DTREE: while (true) { t = table; if (!(index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))) { break; } //int[] h; int i, j, c; t = bb[0]; while (k < (t)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } if (tb[0] == -1) { //System.err.println("null..."); } t = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 1]; c = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 2]; if (c < 16) { b = SupportClass.URShift(b, (t)); k -= (t); blens[index++] = c; } else { // c == 16..18 i = c == 18?7:c - 14; j = c == 18?11:3; while (k < (t + i)) { if (n != 0) { r = Z_OK; } else { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } ; n--; b |= (z.next_in[p++] & 0xff) << k; k += 8; } b = SupportClass.URShift(b, (t)); k -= (t); j += (b & inflate_mask[i]); b = SupportClass.URShift(b, (i)); k -= (i); i = index; t = table; if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || (c == 16 && i < 1)) { blens = null; mode = BAD; z.msg = "invalid bit length repeat"; r = Z_DATA_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } c = c == 16?blens[i - 1]:0; do { blens[i++] = c; }while (--j != 0); index = i; } } tb[0] = -1; { int[] bl = new int[1]; int[] bd = new int[1]; int[] tl = new int[1]; int[] td = new int[1]; bl[0] = 9; // must be <= 9 for lookahead assumptions bd[0] = 6; // must be <= 9 for lookahead assumptions t = table; t = inftree.inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), blens, bl, bd, tl, td, hufts, z); if (t != Z_OK) { if (t == Z_DATA_ERROR) { blens = null; mode = BAD; } r = t; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } codes.init(bl[0], bd[0], hufts, tl[0], hufts, td[0], z); } mode = CODES; goto case CODES; case CODES: bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; if ((r = codes.proc(this, z, r)) != Z_STREAM_END) { return(inflate_flush(z, r)); } r = Z_OK; codes.free(z); p = z.next_in_index; n = z.avail_in; b = bitb; k = bitk; q = write; m = (int)(q < read?read - q - 1:end - q); if (last == 0) { mode = TYPE; break; } mode = DRY; goto case DRY; case DRY: write = q; r = inflate_flush(z, r); q = write; m = (int)(q < read?read - q - 1:end - q); if (read != write) { bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } mode = DONE; goto case DONE; case DONE: r = Z_STREAM_END; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); case BAD: r = Z_DATA_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); default: r = Z_STREAM_ERROR; bitb = b; bitk = k; z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p; write = q; return(inflate_flush(z, r)); } } }
// Mapping from a distance to a distance code. dist is the distance - 1 and // must not have side effects. _dist_code[256] and _dist_code[257] are never // used. internal static int d_code(int dist) { return((dist) < 256?_dist_code[dist]:_dist_code[256 + (SupportClass.URShift((dist), 7))]); }