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author | Christian Beier <[email protected]> | 2018-10-01 20:50:35 +0200 |
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committer | Christian Beier <[email protected]> | 2018-10-01 20:50:35 +0200 |
commit | ffe33574918cf31926ed37caef12f24e73b2d478 (patch) | |
tree | a5402503529c20741556306aff0275ddaa44b159 /webclients/novnc/vendor/pako/lib/zlib/deflate.js | |
parent | de3a2f46b5c4913ba55dfb8c6f7c8b52136bf27a (diff) | |
download | libtdevnc-ffe33574918cf31926ed37caef12f24e73b2d478.tar.gz libtdevnc-ffe33574918cf31926ed37caef12f24e73b2d478.zip |
Update bundled noVNC to latest release 1.0.0
Closes #148
Diffstat (limited to 'webclients/novnc/vendor/pako/lib/zlib/deflate.js')
-rw-r--r-- | webclients/novnc/vendor/pako/lib/zlib/deflate.js | 1846 |
1 files changed, 1846 insertions, 0 deletions
diff --git a/webclients/novnc/vendor/pako/lib/zlib/deflate.js b/webclients/novnc/vendor/pako/lib/zlib/deflate.js new file mode 100644 index 0000000..c51915e --- /dev/null +++ b/webclients/novnc/vendor/pako/lib/zlib/deflate.js @@ -0,0 +1,1846 @@ +import * as utils from "../utils/common.js"; +import * as trees from "./trees.js"; +import adler32 from "./adler32.js"; +import crc32 from "./crc32.js"; +import msg from "./messages.js"; + +/* Public constants ==========================================================*/ +/* ===========================================================================*/ + + +/* Allowed flush values; see deflate() and inflate() below for details */ +var Z_NO_FLUSH = 0; +var Z_PARTIAL_FLUSH = 1; +//var Z_SYNC_FLUSH = 2; +var Z_FULL_FLUSH = 3; +var Z_FINISH = 4; +var Z_BLOCK = 5; +//var Z_TREES = 6; + + +/* Return codes for the compression/decompression functions. Negative values + * are errors, positive values are used for special but normal events. + */ +var Z_OK = 0; +var Z_STREAM_END = 1; +//var Z_NEED_DICT = 2; +//var Z_ERRNO = -1; +var Z_STREAM_ERROR = -2; +var Z_DATA_ERROR = -3; +//var Z_MEM_ERROR = -4; +var Z_BUF_ERROR = -5; +//var Z_VERSION_ERROR = -6; + + +/* compression levels */ +//var Z_NO_COMPRESSION = 0; +//var Z_BEST_SPEED = 1; +//var Z_BEST_COMPRESSION = 9; +var Z_DEFAULT_COMPRESSION = -1; + + +var Z_FILTERED = 1; +var Z_HUFFMAN_ONLY = 2; +var Z_RLE = 3; +var Z_FIXED = 4; +var Z_DEFAULT_STRATEGY = 0; + +/* Possible values of the data_type field (though see inflate()) */ +//var Z_BINARY = 0; +//var Z_TEXT = 1; +//var Z_ASCII = 1; // = Z_TEXT +var Z_UNKNOWN = 2; + + +/* The deflate compression method */ +var Z_DEFLATED = 8; + +/*============================================================================*/ + + +var MAX_MEM_LEVEL = 9; +/* Maximum value for memLevel in deflateInit2 */ +var MAX_WBITS = 15; +/* 32K LZ77 window */ +var DEF_MEM_LEVEL = 8; + + +var LENGTH_CODES = 29; +/* number of length codes, not counting the special END_BLOCK code */ +var LITERALS = 256; +/* number of literal bytes 0..255 */ +var L_CODES = LITERALS + 1 + LENGTH_CODES; +/* number of Literal or Length codes, including the END_BLOCK code */ +var D_CODES = 30; +/* number of distance codes */ +var BL_CODES = 19; +/* number of codes used to transfer the bit lengths */ +var HEAP_SIZE = 2 * L_CODES + 1; +/* maximum heap size */ +var MAX_BITS = 15; +/* All codes must not exceed MAX_BITS bits */ + +var MIN_MATCH = 3; +var MAX_MATCH = 258; +var MIN_LOOKAHEAD = (MAX_MATCH + MIN_MATCH + 1); + +var PRESET_DICT = 0x20; + +var INIT_STATE = 42; +var EXTRA_STATE = 69; +var NAME_STATE = 73; +var COMMENT_STATE = 91; +var HCRC_STATE = 103; +var BUSY_STATE = 113; +var FINISH_STATE = 666; + +var BS_NEED_MORE = 1; /* block not completed, need more input or more output */ +var BS_BLOCK_DONE = 2; /* block flush performed */ +var BS_FINISH_STARTED = 3; /* finish started, need only more output at next deflate */ +var BS_FINISH_DONE = 4; /* finish done, accept no more input or output */ + +var OS_CODE = 0x03; // Unix :) . Don't detect, use this default. + +function err(strm, errorCode) { + strm.msg = msg[errorCode]; + return errorCode; +} + +function rank(f) { + return ((f) << 1) - ((f) > 4 ? 9 : 0); +} + +function zero(buf) { var len = buf.length; while (--len >= 0) { buf[len] = 0; } } + + +/* ========================================================================= + * Flush as much pending output as possible. All deflate() output goes + * through this function so some applications may wish to modify it + * to avoid allocating a large strm->output buffer and copying into it. + * (See also read_buf()). + */ +function flush_pending(strm) { + var s = strm.state; + + //_tr_flush_bits(s); + var len = s.pending; + if (len > strm.avail_out) { + len = strm.avail_out; + } + if (len === 0) { return; } + + utils.arraySet(strm.output, s.pending_buf, s.pending_out, len, strm.next_out); + strm.next_out += len; + s.pending_out += len; + strm.total_out += len; + strm.avail_out -= len; + s.pending -= len; + if (s.pending === 0) { + s.pending_out = 0; + } +} + + +function flush_block_only(s, last) { + trees._tr_flush_block(s, (s.block_start >= 0 ? s.block_start : -1), s.strstart - s.block_start, last); + s.block_start = s.strstart; + flush_pending(s.strm); +} + + +function put_byte(s, b) { + s.pending_buf[s.pending++] = b; +} + + +/* ========================================================================= + * Put a short in the pending buffer. The 16-bit value is put in MSB order. + * IN assertion: the stream state is correct and there is enough room in + * pending_buf. + */ +function putShortMSB(s, b) { +// put_byte(s, (Byte)(b >> 8)); +// put_byte(s, (Byte)(b & 0xff)); + s.pending_buf[s.pending++] = (b >>> 8) & 0xff; + s.pending_buf[s.pending++] = b & 0xff; +} + + +/* =========================================================================== + * Read a new buffer from the current input stream, update the adler32 + * and total number of bytes read. All deflate() input goes through + * this function so some applications may wish to modify it to avoid + * allocating a large strm->input buffer and copying from it. + * (See also flush_pending()). + */ +function read_buf(strm, buf, start, size) { + var len = strm.avail_in; + + if (len > size) { len = size; } + if (len === 0) { return 0; } + + strm.avail_in -= len; + + // zmemcpy(buf, strm->next_in, len); + utils.arraySet(buf, strm.input, strm.next_in, len, start); + if (strm.state.wrap === 1) { + strm.adler = adler32(strm.adler, buf, len, start); + } + + else if (strm.state.wrap === 2) { + strm.adler = crc32(strm.adler, buf, len, start); + } + + strm.next_in += len; + strm.total_in += len; + + return len; +} + + +/* =========================================================================== + * Set match_start to the longest match starting at the given string and + * return its length. Matches shorter or equal to prev_length are discarded, + * in which case the result is equal to prev_length and match_start is + * garbage. + * IN assertions: cur_match is the head of the hash chain for the current + * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 + * OUT assertion: the match length is not greater than s->lookahead. + */ +function longest_match(s, cur_match) { + var chain_length = s.max_chain_length; /* max hash chain length */ + var scan = s.strstart; /* current string */ + var match; /* matched string */ + var len; /* length of current match */ + var best_len = s.prev_length; /* best match length so far */ + var nice_match = s.nice_match; /* stop if match long enough */ + var limit = (s.strstart > (s.w_size - MIN_LOOKAHEAD)) ? + s.strstart - (s.w_size - MIN_LOOKAHEAD) : 0/*NIL*/; + + var _win = s.window; // shortcut + + var wmask = s.w_mask; + var prev = s.prev; + + /* Stop when cur_match becomes <= limit. To simplify the code, + * we prevent matches with the string of window index 0. + */ + + var strend = s.strstart + MAX_MATCH; + var scan_end1 = _win[scan + best_len - 1]; + var scan_end = _win[scan + best_len]; + + /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. + * It is easy to get rid of this optimization if necessary. + */ + // Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); + + /* Do not waste too much time if we already have a good match: */ + if (s.prev_length >= s.good_match) { + chain_length >>= 2; + } + /* Do not look for matches beyond the end of the input. This is necessary + * to make deflate deterministic. + */ + if (nice_match > s.lookahead) { nice_match = s.lookahead; } + + // Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); + + do { + // Assert(cur_match < s->strstart, "no future"); + match = cur_match; + + /* Skip to next match if the match length cannot increase + * or if the match length is less than 2. Note that the checks below + * for insufficient lookahead only occur occasionally for performance + * reasons. Therefore uninitialized memory will be accessed, and + * conditional jumps will be made that depend on those values. + * However the length of the match is limited to the lookahead, so + * the output of deflate is not affected by the uninitialized values. + */ + + if (_win[match + best_len] !== scan_end || + _win[match + best_len - 1] !== scan_end1 || + _win[match] !== _win[scan] || + _win[++match] !== _win[scan + 1]) { + continue; + } + + /* The check at best_len-1 can be removed because it will be made + * again later. (This heuristic is not always a win.) + * It is not necessary to compare scan[2] and match[2] since they + * are always equal when the other bytes match, given that + * the hash keys are equal and that HASH_BITS >= 8. + */ + scan += 2; + match++; + // Assert(*scan == *match, "match[2]?"); + + /* We check for insufficient lookahead only every 8th comparison; + * the 256th check will be made at strstart+258. + */ + do { + // Do nothing + } while (_win[++scan] === _win[++match] && _win[++scan] === _win[++match] && + _win[++scan] === _win[++match] && _win[++scan] === _win[++match] && + _win[++scan] === _win[++match] && _win[++scan] === _win[++match] && + _win[++scan] === _win[++match] && _win[++scan] === _win[++match] && + scan < strend); + + // Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + + len = MAX_MATCH - (strend - scan); + scan = strend - MAX_MATCH; + + if (len > best_len) { + s.match_start = cur_match; + best_len = len; + if (len >= nice_match) { + break; + } + scan_end1 = _win[scan + best_len - 1]; + scan_end = _win[scan + best_len]; + } + } while ((cur_match = prev[cur_match & wmask]) > limit && --chain_length !== 0); + + if (best_len <= s.lookahead) { + return best_len; + } + return s.lookahead; +} + + +/* =========================================================================== + * Fill the window when the lookahead becomes insufficient. + * Updates strstart and lookahead. + * + * IN assertion: lookahead < MIN_LOOKAHEAD + * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD + * At least one byte has been read, or avail_in == 0; reads are + * performed for at least two bytes (required for the zip translate_eol + * option -- not supported here). + */ +function fill_window(s) { + var _w_size = s.w_size; + var p, n, m, more, str; + + //Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead"); + + do { + more = s.window_size - s.lookahead - s.strstart; + + // JS ints have 32 bit, block below not needed + /* Deal with !@#$% 64K limit: */ + //if (sizeof(int) <= 2) { + // if (more == 0 && s->strstart == 0 && s->lookahead == 0) { + // more = wsize; + // + // } else if (more == (unsigned)(-1)) { + // /* Very unlikely, but possible on 16 bit machine if + // * strstart == 0 && lookahead == 1 (input done a byte at time) + // */ + // more--; + // } + //} + + + /* If the window is almost full and there is insufficient lookahead, + * move the upper half to the lower one to make room in the upper half. + */ + if (s.strstart >= _w_size + (_w_size - MIN_LOOKAHEAD)) { + + utils.arraySet(s.window, s.window, _w_size, _w_size, 0); + s.match_start -= _w_size; + s.strstart -= _w_size; + /* we now have strstart >= MAX_DIST */ + s.block_start -= _w_size; + + /* Slide the hash table (could be avoided with 32 bit values + at the expense of memory usage). We slide even when level == 0 + to keep the hash table consistent if we switch back to level > 0 + later. (Using level 0 permanently is not an optimal usage of + zlib, so we don't care about this pathological case.) + */ + + n = s.hash_size; + p = n; + do { + m = s.head[--p]; + s.head[p] = (m >= _w_size ? m - _w_size : 0); + } while (--n); + + n = _w_size; + p = n; + do { + m = s.prev[--p]; + s.prev[p] = (m >= _w_size ? m - _w_size : 0); + /* If n is not on any hash chain, prev[n] is garbage but + * its value will never be used. + */ + } while (--n); + + more += _w_size; + } + if (s.strm.avail_in === 0) { + break; + } + + /* If there was no sliding: + * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && + * more == window_size - lookahead - strstart + * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) + * => more >= window_size - 2*WSIZE + 2 + * In the BIG_MEM or MMAP case (not yet supported), + * window_size == input_size + MIN_LOOKAHEAD && + * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. + * Otherwise, window_size == 2*WSIZE so more >= 2. + * If there was sliding, more >= WSIZE. So in all cases, more >= 2. + */ + //Assert(more >= 2, "more < 2"); + n = read_buf(s.strm, s.window, s.strstart + s.lookahead, more); + s.lookahead += n; + + /* Initialize the hash value now that we have some input: */ + if (s.lookahead + s.insert >= MIN_MATCH) { + str = s.strstart - s.insert; + s.ins_h = s.window[str]; + + /* UPDATE_HASH(s, s->ins_h, s->window[str + 1]); */ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[str + 1]) & s.hash_mask; +//#if MIN_MATCH != 3 +// Call update_hash() MIN_MATCH-3 more times +//#endif + while (s.insert) { + /* UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); */ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[str + MIN_MATCH - 1]) & s.hash_mask; + + s.prev[str & s.w_mask] = s.head[s.ins_h]; + s.head[s.ins_h] = str; + str++; + s.insert--; + if (s.lookahead + s.insert < MIN_MATCH) { + break; + } + } + } + /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, + * but this is not important since only literal bytes will be emitted. + */ + + } while (s.lookahead < MIN_LOOKAHEAD && s.strm.avail_in !== 0); + + /* If the WIN_INIT bytes after the end of the current data have never been + * written, then zero those bytes in order to avoid memory check reports of + * the use of uninitialized (or uninitialised as Julian writes) bytes by + * the longest match routines. Update the high water mark for the next + * time through here. WIN_INIT is set to MAX_MATCH since the longest match + * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead. + */ +// if (s.high_water < s.window_size) { +// var curr = s.strstart + s.lookahead; +// var init = 0; +// +// if (s.high_water < curr) { +// /* Previous high water mark below current data -- zero WIN_INIT +// * bytes or up to end of window, whichever is less. +// */ +// init = s.window_size - curr; +// if (init > WIN_INIT) +// init = WIN_INIT; +// zmemzero(s->window + curr, (unsigned)init); +// s->high_water = curr + init; +// } +// else if (s->high_water < (ulg)curr + WIN_INIT) { +// /* High water mark at or above current data, but below current data +// * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up +// * to end of window, whichever is less. +// */ +// init = (ulg)curr + WIN_INIT - s->high_water; +// if (init > s->window_size - s->high_water) +// init = s->window_size - s->high_water; +// zmemzero(s->window + s->high_water, (unsigned)init); +// s->high_water += init; +// } +// } +// +// Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD, +// "not enough room for search"); +} + +/* =========================================================================== + * Copy without compression as much as possible from the input stream, return + * the current block state. + * This function does not insert new strings in the dictionary since + * uncompressible data is probably not useful. This function is used + * only for the level=0 compression option. + * NOTE: this function should be optimized to avoid extra copying from + * window to pending_buf. + */ +function deflate_stored(s, flush) { + /* Stored blocks are limited to 0xffff bytes, pending_buf is limited + * to pending_buf_size, and each stored block has a 5 byte header: + */ + var max_block_size = 0xffff; + + if (max_block_size > s.pending_buf_size - 5) { + max_block_size = s.pending_buf_size - 5; + } + + /* Copy as much as possible from input to output: */ + for (;;) { + /* Fill the window as much as possible: */ + if (s.lookahead <= 1) { + + //Assert(s->strstart < s->w_size+MAX_DIST(s) || + // s->block_start >= (long)s->w_size, "slide too late"); +// if (!(s.strstart < s.w_size + (s.w_size - MIN_LOOKAHEAD) || +// s.block_start >= s.w_size)) { +// throw new Error("slide too late"); +// } + + fill_window(s); + if (s.lookahead === 0 && flush === Z_NO_FLUSH) { + return BS_NEED_MORE; + } + + if (s.lookahead === 0) { + break; + } + /* flush the current block */ + } + //Assert(s->block_start >= 0L, "block gone"); +// if (s.block_start < 0) throw new Error("block gone"); + + s.strstart += s.lookahead; + s.lookahead = 0; + + /* Emit a stored block if pending_buf will be full: */ + var max_start = s.block_start + max_block_size; + + if (s.strstart === 0 || s.strstart >= max_start) { + /* strstart == 0 is possible when wraparound on 16-bit machine */ + s.lookahead = s.strstart - max_start; + s.strstart = max_start; + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + + + } + /* Flush if we may have to slide, otherwise block_start may become + * negative and the data will be gone: + */ + if (s.strstart - s.block_start >= (s.w_size - MIN_LOOKAHEAD)) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + } + + s.insert = 0; + + if (flush === Z_FINISH) { + /*** FLUSH_BLOCK(s, 1); ***/ + flush_block_only(s, true); + if (s.strm.avail_out === 0) { + return BS_FINISH_STARTED; + } + /***/ + return BS_FINISH_DONE; + } + + if (s.strstart > s.block_start) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + + return BS_NEED_MORE; +} + +/* =========================================================================== + * Compress as much as possible from the input stream, return the current + * block state. + * This function does not perform lazy evaluation of matches and inserts + * new strings in the dictionary only for unmatched strings or for short + * matches. It is used only for the fast compression options. + */ +function deflate_fast(s, flush) { + var hash_head; /* head of the hash chain */ + var bflush; /* set if current block must be flushed */ + + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s.lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s.lookahead < MIN_LOOKAHEAD && flush === Z_NO_FLUSH) { + return BS_NEED_MORE; + } + if (s.lookahead === 0) { + break; /* flush the current block */ + } + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + hash_head = 0/*NIL*/; + if (s.lookahead >= MIN_MATCH) { + /*** INSERT_STRING(s, s.strstart, hash_head); ***/ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[s.strstart + MIN_MATCH - 1]) & s.hash_mask; + hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h]; + s.head[s.ins_h] = s.strstart; + /***/ + } + + /* Find the longest match, discarding those <= prev_length. + * At this point we have always match_length < MIN_MATCH + */ + if (hash_head !== 0/*NIL*/ && ((s.strstart - hash_head) <= (s.w_size - MIN_LOOKAHEAD))) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + s.match_length = longest_match(s, hash_head); + /* longest_match() sets match_start */ + } + if (s.match_length >= MIN_MATCH) { + // check_match(s, s.strstart, s.match_start, s.match_length); // for debug only + + /*** _tr_tally_dist(s, s.strstart - s.match_start, + s.match_length - MIN_MATCH, bflush); ***/ + bflush = trees._tr_tally(s, s.strstart - s.match_start, s.match_length - MIN_MATCH); + + s.lookahead -= s.match_length; + + /* Insert new strings in the hash table only if the match length + * is not too large. This saves time but degrades compression. + */ + if (s.match_length <= s.max_lazy_match/*max_insert_length*/ && s.lookahead >= MIN_MATCH) { + s.match_length--; /* string at strstart already in table */ + do { + s.strstart++; + /*** INSERT_STRING(s, s.strstart, hash_head); ***/ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[s.strstart + MIN_MATCH - 1]) & s.hash_mask; + hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h]; + s.head[s.ins_h] = s.strstart; + /***/ + /* strstart never exceeds WSIZE-MAX_MATCH, so there are + * always MIN_MATCH bytes ahead. + */ + } while (--s.match_length !== 0); + s.strstart++; + } else + { + s.strstart += s.match_length; + s.match_length = 0; + s.ins_h = s.window[s.strstart]; + /* UPDATE_HASH(s, s.ins_h, s.window[s.strstart+1]); */ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[s.strstart + 1]) & s.hash_mask; + +//#if MIN_MATCH != 3 +// Call UPDATE_HASH() MIN_MATCH-3 more times +//#endif + /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not + * matter since it will be recomputed at next deflate call. + */ + } + } else { + /* No match, output a literal byte */ + //Tracevv((stderr,"%c", s.window[s.strstart])); + /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/ + bflush = trees._tr_tally(s, 0, s.window[s.strstart]); + + s.lookahead--; + s.strstart++; + } + if (bflush) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + } + s.insert = ((s.strstart < (MIN_MATCH - 1)) ? s.strstart : MIN_MATCH - 1); + if (flush === Z_FINISH) { + /*** FLUSH_BLOCK(s, 1); ***/ + flush_block_only(s, true); + if (s.strm.avail_out === 0) { + return BS_FINISH_STARTED; + } + /***/ + return BS_FINISH_DONE; + } + if (s.last_lit) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + return BS_BLOCK_DONE; +} + +/* =========================================================================== + * Same as above, but achieves better compression. We use a lazy + * evaluation for matches: a match is finally adopted only if there is + * no better match at the next window position. + */ +function deflate_slow(s, flush) { + var hash_head; /* head of hash chain */ + var bflush; /* set if current block must be flushed */ + + var max_insert; + + /* Process the input block. */ + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s.lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s.lookahead < MIN_LOOKAHEAD && flush === Z_NO_FLUSH) { + return BS_NEED_MORE; + } + if (s.lookahead === 0) { break; } /* flush the current block */ + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + hash_head = 0/*NIL*/; + if (s.lookahead >= MIN_MATCH) { + /*** INSERT_STRING(s, s.strstart, hash_head); ***/ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[s.strstart + MIN_MATCH - 1]) & s.hash_mask; + hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h]; + s.head[s.ins_h] = s.strstart; + /***/ + } + + /* Find the longest match, discarding those <= prev_length. + */ + s.prev_length = s.match_length; + s.prev_match = s.match_start; + s.match_length = MIN_MATCH - 1; + + if (hash_head !== 0/*NIL*/ && s.prev_length < s.max_lazy_match && + s.strstart - hash_head <= (s.w_size - MIN_LOOKAHEAD)/*MAX_DIST(s)*/) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + s.match_length = longest_match(s, hash_head); + /* longest_match() sets match_start */ + + if (s.match_length <= 5 && + (s.strategy === Z_FILTERED || (s.match_length === MIN_MATCH && s.strstart - s.match_start > 4096/*TOO_FAR*/))) { + + /* If prev_match is also MIN_MATCH, match_start is garbage + * but we will ignore the current match anyway. + */ + s.match_length = MIN_MATCH - 1; + } + } + /* If there was a match at the previous step and the current + * match is not better, output the previous match: + */ + if (s.prev_length >= MIN_MATCH && s.match_length <= s.prev_length) { + max_insert = s.strstart + s.lookahead - MIN_MATCH; + /* Do not insert strings in hash table beyond this. */ + + //check_match(s, s.strstart-1, s.prev_match, s.prev_length); + + /***_tr_tally_dist(s, s.strstart - 1 - s.prev_match, + s.prev_length - MIN_MATCH, bflush);***/ + bflush = trees._tr_tally(s, s.strstart - 1 - s.prev_match, s.prev_length - MIN_MATCH); + /* Insert in hash table all strings up to the end of the match. + * strstart-1 and strstart are already inserted. If there is not + * enough lookahead, the last two strings are not inserted in + * the hash table. + */ + s.lookahead -= s.prev_length - 1; + s.prev_length -= 2; + do { + if (++s.strstart <= max_insert) { + /*** INSERT_STRING(s, s.strstart, hash_head); ***/ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[s.strstart + MIN_MATCH - 1]) & s.hash_mask; + hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h]; + s.head[s.ins_h] = s.strstart; + /***/ + } + } while (--s.prev_length !== 0); + s.match_available = 0; + s.match_length = MIN_MATCH - 1; + s.strstart++; + + if (bflush) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + + } else if (s.match_available) { + /* If there was no match at the previous position, output a + * single literal. If there was a match but the current match + * is longer, truncate the previous match to a single literal. + */ + //Tracevv((stderr,"%c", s->window[s->strstart-1])); + /*** _tr_tally_lit(s, s.window[s.strstart-1], bflush); ***/ + bflush = trees._tr_tally(s, 0, s.window[s.strstart - 1]); + + if (bflush) { + /*** FLUSH_BLOCK_ONLY(s, 0) ***/ + flush_block_only(s, false); + /***/ + } + s.strstart++; + s.lookahead--; + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + } else { + /* There is no previous match to compare with, wait for + * the next step to decide. + */ + s.match_available = 1; + s.strstart++; + s.lookahead--; + } + } + //Assert (flush != Z_NO_FLUSH, "no flush?"); + if (s.match_available) { + //Tracevv((stderr,"%c", s->window[s->strstart-1])); + /*** _tr_tally_lit(s, s.window[s.strstart-1], bflush); ***/ + bflush = trees._tr_tally(s, 0, s.window[s.strstart - 1]); + + s.match_available = 0; + } + s.insert = s.strstart < MIN_MATCH - 1 ? s.strstart : MIN_MATCH - 1; + if (flush === Z_FINISH) { + /*** FLUSH_BLOCK(s, 1); ***/ + flush_block_only(s, true); + if (s.strm.avail_out === 0) { + return BS_FINISH_STARTED; + } + /***/ + return BS_FINISH_DONE; + } + if (s.last_lit) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + + return BS_BLOCK_DONE; +} + + +/* =========================================================================== + * For Z_RLE, simply look for runs of bytes, generate matches only of distance + * one. Do not maintain a hash table. (It will be regenerated if this run of + * deflate switches away from Z_RLE.) + */ +function deflate_rle(s, flush) { + var bflush; /* set if current block must be flushed */ + var prev; /* byte at distance one to match */ + var scan, strend; /* scan goes up to strend for length of run */ + + var _win = s.window; + + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the longest run, plus one for the unrolled loop. + */ + if (s.lookahead <= MAX_MATCH) { + fill_window(s); + if (s.lookahead <= MAX_MATCH && flush === Z_NO_FLUSH) { + return BS_NEED_MORE; + } + if (s.lookahead === 0) { break; } /* flush the current block */ + } + + /* See how many times the previous byte repeats */ + s.match_length = 0; + if (s.lookahead >= MIN_MATCH && s.strstart > 0) { + scan = s.strstart - 1; + prev = _win[scan]; + if (prev === _win[++scan] && prev === _win[++scan] && prev === _win[++scan]) { + strend = s.strstart + MAX_MATCH; + do { + // Do nothing + } while (prev === _win[++scan] && prev === _win[++scan] && + prev === _win[++scan] && prev === _win[++scan] && + prev === _win[++scan] && prev === _win[++scan] && + prev === _win[++scan] && prev === _win[++scan] && + scan < strend); + s.match_length = MAX_MATCH - (strend - scan); + if (s.match_length > s.lookahead) { + s.match_length = s.lookahead; + } + } + //Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan"); + } + + /* Emit match if have run of MIN_MATCH or longer, else emit literal */ + if (s.match_length >= MIN_MATCH) { + //check_match(s, s.strstart, s.strstart - 1, s.match_length); + + /*** _tr_tally_dist(s, 1, s.match_length - MIN_MATCH, bflush); ***/ + bflush = trees._tr_tally(s, 1, s.match_length - MIN_MATCH); + + s.lookahead -= s.match_length; + s.strstart += s.match_length; + s.match_length = 0; + } else { + /* No match, output a literal byte */ + //Tracevv((stderr,"%c", s->window[s->strstart])); + /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/ + bflush = trees._tr_tally(s, 0, s.window[s.strstart]); + + s.lookahead--; + s.strstart++; + } + if (bflush) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + } + s.insert = 0; + if (flush === Z_FINISH) { + /*** FLUSH_BLOCK(s, 1); ***/ + flush_block_only(s, true); + if (s.strm.avail_out === 0) { + return BS_FINISH_STARTED; + } + /***/ + return BS_FINISH_DONE; + } + if (s.last_lit) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + return BS_BLOCK_DONE; +} + +/* =========================================================================== + * For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table. + * (It will be regenerated if this run of deflate switches away from Huffman.) + */ +function deflate_huff(s, flush) { + var bflush; /* set if current block must be flushed */ + + for (;;) { + /* Make sure that we have a literal to write. */ + if (s.lookahead === 0) { + fill_window(s); + if (s.lookahead === 0) { + if (flush === Z_NO_FLUSH) { + return BS_NEED_MORE; + } + break; /* flush the current block */ + } + } + + /* Output a literal byte */ + s.match_length = 0; + //Tracevv((stderr,"%c", s->window[s->strstart])); + /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/ + bflush = trees._tr_tally(s, 0, s.window[s.strstart]); + s.lookahead--; + s.strstart++; + if (bflush) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + } + s.insert = 0; + if (flush === Z_FINISH) { + /*** FLUSH_BLOCK(s, 1); ***/ + flush_block_only(s, true); + if (s.strm.avail_out === 0) { + return BS_FINISH_STARTED; + } + /***/ + return BS_FINISH_DONE; + } + if (s.last_lit) { + /*** FLUSH_BLOCK(s, 0); ***/ + flush_block_only(s, false); + if (s.strm.avail_out === 0) { + return BS_NEED_MORE; + } + /***/ + } + return BS_BLOCK_DONE; +} + +/* Values for max_lazy_match, good_match and max_chain_length, depending on + * the desired pack level (0..9). The values given below have been tuned to + * exclude worst case performance for pathological files. Better values may be + * found for specific files. + */ +function Config(good_length, max_lazy, nice_length, max_chain, func) { + this.good_length = good_length; + this.max_lazy = max_lazy; + this.nice_length = nice_length; + this.max_chain = max_chain; + this.func = func; +} + +var configuration_table; + +configuration_table = [ + /* good lazy nice chain */ + new Config(0, 0, 0, 0, deflate_stored), /* 0 store only */ + new Config(4, 4, 8, 4, deflate_fast), /* 1 max speed, no lazy matches */ + new Config(4, 5, 16, 8, deflate_fast), /* 2 */ + new Config(4, 6, 32, 32, deflate_fast), /* 3 */ + + new Config(4, 4, 16, 16, deflate_slow), /* 4 lazy matches */ + new Config(8, 16, 32, 32, deflate_slow), /* 5 */ + new Config(8, 16, 128, 128, deflate_slow), /* 6 */ + new Config(8, 32, 128, 256, deflate_slow), /* 7 */ + new Config(32, 128, 258, 1024, deflate_slow), /* 8 */ + new Config(32, 258, 258, 4096, deflate_slow) /* 9 max compression */ +]; + + +/* =========================================================================== + * Initialize the "longest match" routines for a new zlib stream + */ +function lm_init(s) { + s.window_size = 2 * s.w_size; + + /*** CLEAR_HASH(s); ***/ + zero(s.head); // Fill with NIL (= 0); + + /* Set the default configuration parameters: + */ + s.max_lazy_match = configuration_table[s.level].max_lazy; + s.good_match = configuration_table[s.level].good_length; + s.nice_match = configuration_table[s.level].nice_length; + s.max_chain_length = configuration_table[s.level].max_chain; + + s.strstart = 0; + s.block_start = 0; + s.lookahead = 0; + s.insert = 0; + s.match_length = s.prev_length = MIN_MATCH - 1; + s.match_available = 0; + s.ins_h = 0; +} + + +function DeflateState() { + this.strm = null; /* pointer back to this zlib stream */ + this.status = 0; /* as the name implies */ + this.pending_buf = null; /* output still pending */ + this.pending_buf_size = 0; /* size of pending_buf */ + this.pending_out = 0; /* next pending byte to output to the stream */ + this.pending = 0; /* nb of bytes in the pending buffer */ + this.wrap = 0; /* bit 0 true for zlib, bit 1 true for gzip */ + this.gzhead = null; /* gzip header information to write */ + this.gzindex = 0; /* where in extra, name, or comment */ + this.method = Z_DEFLATED; /* can only be DEFLATED */ + this.last_flush = -1; /* value of flush param for previous deflate call */ + + this.w_size = 0; /* LZ77 window size (32K by default) */ + this.w_bits = 0; /* log2(w_size) (8..16) */ + this.w_mask = 0; /* w_size - 1 */ + + this.window = null; + /* Sliding window. Input bytes are read into the second half of the window, + * and move to the first half later to keep a dictionary of at least wSize + * bytes. With this organization, matches are limited to a distance of + * wSize-MAX_MATCH bytes, but this ensures that IO is always + * performed with a length multiple of the block size. + */ + + this.window_size = 0; + /* Actual size of window: 2*wSize, except when the user input buffer + * is directly used as sliding window. + */ + + this.prev = null; + /* Link to older string with same hash index. To limit the size of this + * array to 64K, this link is maintained only for the last 32K strings. + * An index in this array is thus a window index modulo 32K. + */ + + this.head = null; /* Heads of the hash chains or NIL. */ + + this.ins_h = 0; /* hash index of string to be inserted */ + this.hash_size = 0; /* number of elements in hash table */ + this.hash_bits = 0; /* log2(hash_size) */ + this.hash_mask = 0; /* hash_size-1 */ + + this.hash_shift = 0; + /* Number of bits by which ins_h must be shifted at each input + * step. It must be such that after MIN_MATCH steps, the oldest + * byte no longer takes part in the hash key, that is: + * hash_shift * MIN_MATCH >= hash_bits + */ + + this.block_start = 0; + /* Window position at the beginning of the current output block. Gets + * negative when the window is moved backwards. + */ + + this.match_length = 0; /* length of best match */ + this.prev_match = 0; /* previous match */ + this.match_available = 0; /* set if previous match exists */ + this.strstart = 0; /* start of string to insert */ + this.match_start = 0; /* start of matching string */ + this.lookahead = 0; /* number of valid bytes ahead in window */ + + this.prev_length = 0; + /* Length of the best match at previous step. Matches not greater than this + * are discarded. This is used in the lazy match evaluation. + */ + + this.max_chain_length = 0; + /* To speed up deflation, hash chains are never searched beyond this + * length. A higher limit improves compression ratio but degrades the + * speed. + */ + + this.max_lazy_match = 0; + /* Attempt to find a better match only when the current match is strictly + * smaller than this value. This mechanism is used only for compression + * levels >= 4. + */ + // That's alias to max_lazy_match, don't use directly + //this.max_insert_length = 0; + /* Insert new strings in the hash table only if the match length is not + * greater than this length. This saves time but degrades compression. + * max_insert_length is used only for compression levels <= 3. + */ + + this.level = 0; /* compression level (1..9) */ + this.strategy = 0; /* favor or force Huffman coding*/ + + this.good_match = 0; + /* Use a faster search when the previous match is longer than this */ + + this.nice_match = 0; /* Stop searching when current match exceeds this */ + + /* used by trees.c: */ + + /* Didn't use ct_data typedef below to suppress compiler warning */ + + // struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */ + // struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */ + // struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */ + + // Use flat array of DOUBLE size, with interleaved fata, + // because JS does not support effective + this.dyn_ltree = new utils.Buf16(HEAP_SIZE * 2); + this.dyn_dtree = new utils.Buf16((2 * D_CODES + 1) * 2); + this.bl_tree = new utils.Buf16((2 * BL_CODES + 1) * 2); + zero(this.dyn_ltree); + zero(this.dyn_dtree); + zero(this.bl_tree); + + this.l_desc = null; /* desc. for literal tree */ + this.d_desc = null; /* desc. for distance tree */ + this.bl_desc = null; /* desc. for bit length tree */ + + //ush bl_count[MAX_BITS+1]; + this.bl_count = new utils.Buf16(MAX_BITS + 1); + /* number of codes at each bit length for an optimal tree */ + + //int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */ + this.heap = new utils.Buf16(2 * L_CODES + 1); /* heap used to build the Huffman trees */ + zero(this.heap); + + this.heap_len = 0; /* number of elements in the heap */ + this.heap_max = 0; /* element of largest frequency */ + /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. + * The same heap array is used to build all trees. + */ + + this.depth = new utils.Buf16(2 * L_CODES + 1); //uch depth[2*L_CODES+1]; + zero(this.depth); + /* Depth of each subtree used as tie breaker for trees of equal frequency + */ + + this.l_buf = 0; /* buffer index for literals or lengths */ + + this.lit_bufsize = 0; + /* Size of match buffer for literals/lengths. There are 4 reasons for + * limiting lit_bufsize to 64K: + * - frequencies can be kept in 16 bit counters + * - if compression is not successful for the first block, all input + * data is still in the window so we can still emit a stored block even + * when input comes from standard input. (This can also be done for + * all blocks if lit_bufsize is not greater than 32K.) + * - if compression is not successful for a file smaller than 64K, we can + * even emit a stored file instead of a stored block (saving 5 bytes). + * This is applicable only for zip (not gzip or zlib). + * - creating new Huffman trees less frequently may not provide fast + * adaptation to changes in the input data statistics. (Take for + * example a binary file with poorly compressible code followed by + * a highly compressible string table.) Smaller buffer sizes give + * fast adaptation but have of course the overhead of transmitting + * trees more frequently. + * - I can't count above 4 + */ + + this.last_lit = 0; /* running index in l_buf */ + + this.d_buf = 0; + /* Buffer index for distances. To simplify the code, d_buf and l_buf have + * the same number of elements. To use different lengths, an extra flag + * array would be necessary. + */ + + this.opt_len = 0; /* bit length of current block with optimal trees */ + this.static_len = 0; /* bit length of current block with static trees */ + this.matches = 0; /* number of string matches in current block */ + this.insert = 0; /* bytes at end of window left to insert */ + + + this.bi_buf = 0; + /* Output buffer. bits are inserted starting at the bottom (least + * significant bits). + */ + this.bi_valid = 0; + /* Number of valid bits in bi_buf. All bits above the last valid bit + * are always zero. + */ + + // Used for window memory init. We safely ignore it for JS. That makes + // sense only for pointers and memory check tools. + //this.high_water = 0; + /* High water mark offset in window for initialized bytes -- bytes above + * this are set to zero in order to avoid memory check warnings when + * longest match routines access bytes past the input. This is then + * updated to the new high water mark. + */ +} + + +function deflateResetKeep(strm) { + var s; + + if (!strm || !strm.state) { + return err(strm, Z_STREAM_ERROR); + } + + strm.total_in = strm.total_out = 0; + strm.data_type = Z_UNKNOWN; + + s = strm.state; + s.pending = 0; + s.pending_out = 0; + + if (s.wrap < 0) { + s.wrap = -s.wrap; + /* was made negative by deflate(..., Z_FINISH); */ + } + s.status = (s.wrap ? INIT_STATE : BUSY_STATE); + strm.adler = (s.wrap === 2) ? + 0 // crc32(0, Z_NULL, 0) + : + 1; // adler32(0, Z_NULL, 0) + s.last_flush = Z_NO_FLUSH; + trees._tr_init(s); + return Z_OK; +} + + +function deflateReset(strm) { + var ret = deflateResetKeep(strm); + if (ret === Z_OK) { + lm_init(strm.state); + } + return ret; +} + + +function deflateSetHeader(strm, head) { + if (!strm || !strm.state) { return Z_STREAM_ERROR; } + if (strm.state.wrap !== 2) { return Z_STREAM_ERROR; } + strm.state.gzhead = head; + return Z_OK; +} + + +function deflateInit2(strm, level, method, windowBits, memLevel, strategy) { + if (!strm) { // === Z_NULL + return Z_STREAM_ERROR; + } + var wrap = 1; + + if (level === Z_DEFAULT_COMPRESSION) { + level = 6; + } + + if (windowBits < 0) { /* suppress zlib wrapper */ + wrap = 0; + windowBits = -windowBits; + } + + else if (windowBits > 15) { + wrap = 2; /* write gzip wrapper instead */ + windowBits -= 16; + } + + + if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method !== Z_DEFLATED || + windowBits < 8 || windowBits > 15 || level < 0 || level > 9 || + strategy < 0 || strategy > Z_FIXED) { + return err(strm, Z_STREAM_ERROR); + } + + + if (windowBits === 8) { + windowBits = 9; + } + /* until 256-byte window bug fixed */ + + var s = new DeflateState(); + + strm.state = s; + s.strm = strm; + + s.wrap = wrap; + s.gzhead = null; + s.w_bits = windowBits; + s.w_size = 1 << s.w_bits; + s.w_mask = s.w_size - 1; + + s.hash_bits = memLevel + 7; + s.hash_size = 1 << s.hash_bits; + s.hash_mask = s.hash_size - 1; + s.hash_shift = ~~((s.hash_bits + MIN_MATCH - 1) / MIN_MATCH); + + s.window = new utils.Buf8(s.w_size * 2); + s.head = new utils.Buf16(s.hash_size); + s.prev = new utils.Buf16(s.w_size); + + // Don't need mem init magic for JS. + //s.high_water = 0; /* nothing written to s->window yet */ + + s.lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ + + s.pending_buf_size = s.lit_bufsize * 4; + + //overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); + //s->pending_buf = (uchf *) overlay; + s.pending_buf = new utils.Buf8(s.pending_buf_size); + + // It is offset from `s.pending_buf` (size is `s.lit_bufsize * 2`) + //s->d_buf = overlay + s->lit_bufsize/sizeof(ush); + s.d_buf = 1 * s.lit_bufsize; + + //s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; + s.l_buf = (1 + 2) * s.lit_bufsize; + + s.level = level; + s.strategy = strategy; + s.method = method; + + return deflateReset(strm); +} + +function deflateInit(strm, level) { + return deflateInit2(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY); +} + + +function deflate(strm, flush) { + var old_flush, s; + var beg, val; // for gzip header write only + + if (!strm || !strm.state || + flush > Z_BLOCK || flush < 0) { + return strm ? err(strm, Z_STREAM_ERROR) : Z_STREAM_ERROR; + } + + s = strm.state; + + if (!strm.output || + (!strm.input && strm.avail_in !== 0) || + (s.status === FINISH_STATE && flush !== Z_FINISH)) { + return err(strm, (strm.avail_out === 0) ? Z_BUF_ERROR : Z_STREAM_ERROR); + } + + s.strm = strm; /* just in case */ + old_flush = s.last_flush; + s.last_flush = flush; + + /* Write the header */ + if (s.status === INIT_STATE) { + + if (s.wrap === 2) { // GZIP header + strm.adler = 0; //crc32(0L, Z_NULL, 0); + put_byte(s, 31); + put_byte(s, 139); + put_byte(s, 8); + if (!s.gzhead) { // s->gzhead == Z_NULL + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, 0); + put_byte(s, s.level === 9 ? 2 : + (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2 ? + 4 : 0)); + put_byte(s, OS_CODE); + s.status = BUSY_STATE; + } + else { + put_byte(s, (s.gzhead.text ? 1 : 0) + + (s.gzhead.hcrc ? 2 : 0) + + (!s.gzhead.extra ? 0 : 4) + + (!s.gzhead.name ? 0 : 8) + + (!s.gzhead.comment ? 0 : 16) + ); + put_byte(s, s.gzhead.time & 0xff); + put_byte(s, (s.gzhead.time >> 8) & 0xff); + put_byte(s, (s.gzhead.time >> 16) & 0xff); + put_byte(s, (s.gzhead.time >> 24) & 0xff); + put_byte(s, s.level === 9 ? 2 : + (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2 ? + 4 : 0)); + put_byte(s, s.gzhead.os & 0xff); + if (s.gzhead.extra && s.gzhead.extra.length) { + put_byte(s, s.gzhead.extra.length & 0xff); + put_byte(s, (s.gzhead.extra.length >> 8) & 0xff); + } + if (s.gzhead.hcrc) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending, 0); + } + s.gzindex = 0; + s.status = EXTRA_STATE; + } + } + else // DEFLATE header + { + var header = (Z_DEFLATED + ((s.w_bits - 8) << 4)) << 8; + var level_flags = -1; + + if (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2) { + level_flags = 0; + } else if (s.level < 6) { + level_flags = 1; + } else if (s.level === 6) { + level_flags = 2; + } else { + level_flags = 3; + } + header |= (level_flags << 6); + if (s.strstart !== 0) { header |= PRESET_DICT; } + header += 31 - (header % 31); + + s.status = BUSY_STATE; + putShortMSB(s, header); + + /* Save the adler32 of the preset dictionary: */ + if (s.strstart !== 0) { + putShortMSB(s, strm.adler >>> 16); + putShortMSB(s, strm.adler & 0xffff); + } + strm.adler = 1; // adler32(0L, Z_NULL, 0); + } + } + +//#ifdef GZIP + if (s.status === EXTRA_STATE) { + if (s.gzhead.extra/* != Z_NULL*/) { + beg = s.pending; /* start of bytes to update crc */ + + while (s.gzindex < (s.gzhead.extra.length & 0xffff)) { + if (s.pending === s.pending_buf_size) { + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + flush_pending(strm); + beg = s.pending; + if (s.pending === s.pending_buf_size) { + break; + } + } + put_byte(s, s.gzhead.extra[s.gzindex] & 0xff); + s.gzindex++; + } + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + if (s.gzindex === s.gzhead.extra.length) { + s.gzindex = 0; + s.status = NAME_STATE; + } + } + else { + s.status = NAME_STATE; + } + } + if (s.status === NAME_STATE) { + if (s.gzhead.name/* != Z_NULL*/) { + beg = s.pending; /* start of bytes to update crc */ + //int val; + + do { + if (s.pending === s.pending_buf_size) { + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + flush_pending(strm); + beg = s.pending; + if (s.pending === s.pending_buf_size) { + val = 1; + break; + } + } + // JS specific: little magic to add zero terminator to end of string + if (s.gzindex < s.gzhead.name.length) { + val = s.gzhead.name.charCodeAt(s.gzindex++) & 0xff; + } else { + val = 0; + } + put_byte(s, val); + } while (val !== 0); + + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + if (val === 0) { + s.gzindex = 0; + s.status = COMMENT_STATE; + } + } + else { + s.status = COMMENT_STATE; + } + } + if (s.status === COMMENT_STATE) { + if (s.gzhead.comment/* != Z_NULL*/) { + beg = s.pending; /* start of bytes to update crc */ + //int val; + + do { + if (s.pending === s.pending_buf_size) { + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + flush_pending(strm); + beg = s.pending; + if (s.pending === s.pending_buf_size) { + val = 1; + break; + } + } + // JS specific: little magic to add zero terminator to end of string + if (s.gzindex < s.gzhead.comment.length) { + val = s.gzhead.comment.charCodeAt(s.gzindex++) & 0xff; + } else { + val = 0; + } + put_byte(s, val); + } while (val !== 0); + + if (s.gzhead.hcrc && s.pending > beg) { + strm.adler = crc32(strm.adler, s.pending_buf, s.pending - beg, beg); + } + if (val === 0) { + s.status = HCRC_STATE; + } + } + else { + s.status = HCRC_STATE; + } + } + if (s.status === HCRC_STATE) { + if (s.gzhead.hcrc) { + if (s.pending + 2 > s.pending_buf_size) { + flush_pending(strm); + } + if (s.pending + 2 <= s.pending_buf_size) { + put_byte(s, strm.adler & 0xff); + put_byte(s, (strm.adler >> 8) & 0xff); + strm.adler = 0; //crc32(0L, Z_NULL, 0); + s.status = BUSY_STATE; + } + } + else { + s.status = BUSY_STATE; + } + } +//#endif + + /* Flush as much pending output as possible */ + if (s.pending !== 0) { + flush_pending(strm); + if (strm.avail_out === 0) { + /* Since avail_out is 0, deflate will be called again with + * more output space, but possibly with both pending and + * avail_in equal to zero. There won't be anything to do, + * but this is not an error situation so make sure we + * return OK instead of BUF_ERROR at next call of deflate: + */ + s.last_flush = -1; + return Z_OK; + } + + /* Make sure there is something to do and avoid duplicate consecutive + * flushes. For repeated and useless calls with Z_FINISH, we keep + * returning Z_STREAM_END instead of Z_BUF_ERROR. + */ + } else if (strm.avail_in === 0 && rank(flush) <= rank(old_flush) && + flush !== Z_FINISH) { + return err(strm, Z_BUF_ERROR); + } + + /* User must not provide more input after the first FINISH: */ + if (s.status === FINISH_STATE && strm.avail_in !== 0) { + return err(strm, Z_BUF_ERROR); + } + + /* Start a new block or continue the current one. + */ + if (strm.avail_in !== 0 || s.lookahead !== 0 || + (flush !== Z_NO_FLUSH && s.status !== FINISH_STATE)) { + var bstate = (s.strategy === Z_HUFFMAN_ONLY) ? deflate_huff(s, flush) : + (s.strategy === Z_RLE ? deflate_rle(s, flush) : + configuration_table[s.level].func(s, flush)); + + if (bstate === BS_FINISH_STARTED || bstate === BS_FINISH_DONE) { + s.status = FINISH_STATE; + } + if (bstate === BS_NEED_MORE || bstate === BS_FINISH_STARTED) { + if (strm.avail_out === 0) { + s.last_flush = -1; + /* avoid BUF_ERROR next call, see above */ + } + return Z_OK; + /* If flush != Z_NO_FLUSH && avail_out == 0, the next call + * of deflate should use the same flush parameter to make sure + * that the flush is complete. So we don't have to output an + * empty block here, this will be done at next call. This also + * ensures that for a very small output buffer, we emit at most + * one empty block. + */ + } + if (bstate === BS_BLOCK_DONE) { + if (flush === Z_PARTIAL_FLUSH) { + trees._tr_align(s); + } + else if (flush !== Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */ + + trees._tr_stored_block(s, 0, 0, false); + /* For a full flush, this empty block will be recognized + * as a special marker by inflate_sync(). + */ + if (flush === Z_FULL_FLUSH) { + /*** CLEAR_HASH(s); ***/ /* forget history */ + zero(s.head); // Fill with NIL (= 0); + + if (s.lookahead === 0) { + s.strstart = 0; + s.block_start = 0; + s.insert = 0; + } + } + } + flush_pending(strm); + if (strm.avail_out === 0) { + s.last_flush = -1; /* avoid BUF_ERROR at next call, see above */ + return Z_OK; + } + } + } + //Assert(strm->avail_out > 0, "bug2"); + //if (strm.avail_out <= 0) { throw new Error("bug2");} + + if (flush !== Z_FINISH) { return Z_OK; } + if (s.wrap <= 0) { return Z_STREAM_END; } + + /* Write the trailer */ + if (s.wrap === 2) { + put_byte(s, strm.adler & 0xff); + put_byte(s, (strm.adler >> 8) & 0xff); + put_byte(s, (strm.adler >> 16) & 0xff); + put_byte(s, (strm.adler >> 24) & 0xff); + put_byte(s, strm.total_in & 0xff); + put_byte(s, (strm.total_in >> 8) & 0xff); + put_byte(s, (strm.total_in >> 16) & 0xff); + put_byte(s, (strm.total_in >> 24) & 0xff); + } + else + { + putShortMSB(s, strm.adler >>> 16); + putShortMSB(s, strm.adler & 0xffff); + } + + flush_pending(strm); + /* If avail_out is zero, the application will call deflate again + * to flush the rest. + */ + if (s.wrap > 0) { s.wrap = -s.wrap; } + /* write the trailer only once! */ + return s.pending !== 0 ? Z_OK : Z_STREAM_END; +} + +function deflateEnd(strm) { + var status; + + if (!strm/*== Z_NULL*/ || !strm.state/*== Z_NULL*/) { + return Z_STREAM_ERROR; + } + + status = strm.state.status; + if (status !== INIT_STATE && + status !== EXTRA_STATE && + status !== NAME_STATE && + status !== COMMENT_STATE && + status !== HCRC_STATE && + status !== BUSY_STATE && + status !== FINISH_STATE + ) { + return err(strm, Z_STREAM_ERROR); + } + + strm.state = null; + + return status === BUSY_STATE ? err(strm, Z_DATA_ERROR) : Z_OK; +} + + +/* ========================================================================= + * Initializes the compression dictionary from the given byte + * sequence without producing any compressed output. + */ +function deflateSetDictionary(strm, dictionary) { + var dictLength = dictionary.length; + + var s; + var str, n; + var wrap; + var avail; + var next; + var input; + var tmpDict; + + if (!strm/*== Z_NULL*/ || !strm.state/*== Z_NULL*/) { + return Z_STREAM_ERROR; + } + + s = strm.state; + wrap = s.wrap; + + if (wrap === 2 || (wrap === 1 && s.status !== INIT_STATE) || s.lookahead) { + return Z_STREAM_ERROR; + } + + /* when using zlib wrappers, compute Adler-32 for provided dictionary */ + if (wrap === 1) { + /* adler32(strm->adler, dictionary, dictLength); */ + strm.adler = adler32(strm.adler, dictionary, dictLength, 0); + } + + s.wrap = 0; /* avoid computing Adler-32 in read_buf */ + + /* if dictionary would fill window, just replace the history */ + if (dictLength >= s.w_size) { + if (wrap === 0) { /* already empty otherwise */ + /*** CLEAR_HASH(s); ***/ + zero(s.head); // Fill with NIL (= 0); + s.strstart = 0; + s.block_start = 0; + s.insert = 0; + } + /* use the tail */ + // dictionary = dictionary.slice(dictLength - s.w_size); + tmpDict = new utils.Buf8(s.w_size); + utils.arraySet(tmpDict, dictionary, dictLength - s.w_size, s.w_size, 0); + dictionary = tmpDict; + dictLength = s.w_size; + } + /* insert dictionary into window and hash */ + avail = strm.avail_in; + next = strm.next_in; + input = strm.input; + strm.avail_in = dictLength; + strm.next_in = 0; + strm.input = dictionary; + fill_window(s); + while (s.lookahead >= MIN_MATCH) { + str = s.strstart; + n = s.lookahead - (MIN_MATCH - 1); + do { + /* UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); */ + s.ins_h = ((s.ins_h << s.hash_shift) ^ s.window[str + MIN_MATCH - 1]) & s.hash_mask; + + s.prev[str & s.w_mask] = s.head[s.ins_h]; + + s.head[s.ins_h] = str; + str++; + } while (--n); + s.strstart = str; + s.lookahead = MIN_MATCH - 1; + fill_window(s); + } + s.strstart += s.lookahead; + s.block_start = s.strstart; + s.insert = s.lookahead; + s.lookahead = 0; + s.match_length = s.prev_length = MIN_MATCH - 1; + s.match_available = 0; + strm.next_in = next; + strm.input = input; + strm.avail_in = avail; + s.wrap = wrap; + return Z_OK; +} + + +export { deflateInit, deflateInit2, deflateReset, deflateResetKeep, deflateSetHeader, deflate, deflateEnd, deflateSetDictionary }; +export var deflateInfo = 'pako deflate (from Nodeca project)'; + +/* Not implemented +exports.deflateBound = deflateBound; +exports.deflateCopy = deflateCopy; +exports.deflateParams = deflateParams; +exports.deflatePending = deflatePending; +exports.deflatePrime = deflatePrime; +exports.deflateTune = deflateTune; +*/ |