diff options
Diffstat (limited to 'school/node_modules/pako/lib/zlib/inffast.js')
-rw-r--r-- | school/node_modules/pako/lib/zlib/inffast.js | 345 |
1 files changed, 0 insertions, 345 deletions
diff --git a/school/node_modules/pako/lib/zlib/inffast.js b/school/node_modules/pako/lib/zlib/inffast.js deleted file mode 100644 index 4cc958f..0000000 --- a/school/node_modules/pako/lib/zlib/inffast.js +++ /dev/null @@ -1,345 +0,0 @@ -'use strict'; - -// (C) 1995-2013 Jean-loup Gailly and Mark Adler -// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin -// -// This software is provided 'as-is', without any express or implied -// warranty. In no event will the authors be held liable for any damages -// arising from the use of this software. -// -// Permission is granted to anyone to use this software for any purpose, -// including commercial applications, and to alter it and redistribute it -// freely, subject to the following restrictions: -// -// 1. The origin of this software must not be misrepresented; you must not -// claim that you wrote the original software. If you use this software -// in a product, an acknowledgment in the product documentation would be -// appreciated but is not required. -// 2. Altered source versions must be plainly marked as such, and must not be -// misrepresented as being the original software. -// 3. This notice may not be removed or altered from any source distribution. - -// See state defs from inflate.js -var BAD = 30; /* got a data error -- remain here until reset */ -var TYPE = 12; /* i: waiting for type bits, including last-flag bit */ - -/* - Decode literal, length, and distance codes and write out the resulting - literal and match bytes until either not enough input or output is - available, an end-of-block is encountered, or a data error is encountered. - When large enough input and output buffers are supplied to inflate(), for - example, a 16K input buffer and a 64K output buffer, more than 95% of the - inflate execution time is spent in this routine. - - Entry assumptions: - - state.mode === LEN - strm.avail_in >= 6 - strm.avail_out >= 258 - start >= strm.avail_out - state.bits < 8 - - On return, state.mode is one of: - - LEN -- ran out of enough output space or enough available input - TYPE -- reached end of block code, inflate() to interpret next block - BAD -- error in block data - - Notes: - - - The maximum input bits used by a length/distance pair is 15 bits for the - length code, 5 bits for the length extra, 15 bits for the distance code, - and 13 bits for the distance extra. This totals 48 bits, or six bytes. - Therefore if strm.avail_in >= 6, then there is enough input to avoid - checking for available input while decoding. - - - The maximum bytes that a single length/distance pair can output is 258 - bytes, which is the maximum length that can be coded. inflate_fast() - requires strm.avail_out >= 258 for each loop to avoid checking for - output space. - */ -module.exports = function inflate_fast(strm, start) { - var state; - var _in; /* local strm.input */ - var last; /* have enough input while in < last */ - var _out; /* local strm.output */ - var beg; /* inflate()'s initial strm.output */ - var end; /* while out < end, enough space available */ -//#ifdef INFLATE_STRICT - var dmax; /* maximum distance from zlib header */ -//#endif - var wsize; /* window size or zero if not using window */ - var whave; /* valid bytes in the window */ - var wnext; /* window write index */ - // Use `s_window` instead `window`, avoid conflict with instrumentation tools - var s_window; /* allocated sliding window, if wsize != 0 */ - var hold; /* local strm.hold */ - var bits; /* local strm.bits */ - var lcode; /* local strm.lencode */ - var dcode; /* local strm.distcode */ - var lmask; /* mask for first level of length codes */ - var dmask; /* mask for first level of distance codes */ - var here; /* retrieved table entry */ - var op; /* code bits, operation, extra bits, or */ - /* window position, window bytes to copy */ - var len; /* match length, unused bytes */ - var dist; /* match distance */ - var from; /* where to copy match from */ - var from_source; - - - var input, output; // JS specific, because we have no pointers - - /* copy state to local variables */ - state = strm.state; - //here = state.here; - _in = strm.next_in; - input = strm.input; - last = _in + (strm.avail_in - 5); - _out = strm.next_out; - output = strm.output; - beg = _out - (start - strm.avail_out); - end = _out + (strm.avail_out - 257); -//#ifdef INFLATE_STRICT - dmax = state.dmax; -//#endif - wsize = state.wsize; - whave = state.whave; - wnext = state.wnext; - s_window = state.window; - hold = state.hold; - bits = state.bits; - lcode = state.lencode; - dcode = state.distcode; - lmask = (1 << state.lenbits) - 1; - dmask = (1 << state.distbits) - 1; - - - /* decode literals and length/distances until end-of-block or not enough - input data or output space */ - - top: - do { - if (bits < 15) { - hold += input[_in++] << bits; - bits += 8; - hold += input[_in++] << bits; - bits += 8; - } - - here = lcode[hold & lmask]; - - dolen: - for (;;) { // Goto emulation - op = here >>> 24/*here.bits*/; - hold >>>= op; - bits -= op; - op = (here >>> 16) & 0xff/*here.op*/; - if (op === 0) { /* literal */ - //Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? - // "inflate: literal '%c'\n" : - // "inflate: literal 0x%02x\n", here.val)); - output[_out++] = here & 0xffff/*here.val*/; - } - else if (op & 16) { /* length base */ - len = here & 0xffff/*here.val*/; - op &= 15; /* number of extra bits */ - if (op) { - if (bits < op) { - hold += input[_in++] << bits; - bits += 8; - } - len += hold & ((1 << op) - 1); - hold >>>= op; - bits -= op; - } - //Tracevv((stderr, "inflate: length %u\n", len)); - if (bits < 15) { - hold += input[_in++] << bits; - bits += 8; - hold += input[_in++] << bits; - bits += 8; - } - here = dcode[hold & dmask]; - - dodist: - for (;;) { // goto emulation - op = here >>> 24/*here.bits*/; - hold >>>= op; - bits -= op; - op = (here >>> 16) & 0xff/*here.op*/; - - if (op & 16) { /* distance base */ - dist = here & 0xffff/*here.val*/; - op &= 15; /* number of extra bits */ - if (bits < op) { - hold += input[_in++] << bits; - bits += 8; - if (bits < op) { - hold += input[_in++] << bits; - bits += 8; - } - } - dist += hold & ((1 << op) - 1); -//#ifdef INFLATE_STRICT - if (dist > dmax) { - strm.msg = 'invalid distance too far back'; - state.mode = BAD; - break top; - } -//#endif - hold >>>= op; - bits -= op; - //Tracevv((stderr, "inflate: distance %u\n", dist)); - op = _out - beg; /* max distance in output */ - if (dist > op) { /* see if copy from window */ - op = dist - op; /* distance back in window */ - if (op > whave) { - if (state.sane) { - strm.msg = 'invalid distance too far back'; - state.mode = BAD; - break top; - } - -// (!) This block is disabled in zlib defaults, -// don't enable it for binary compatibility -//#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR -// if (len <= op - whave) { -// do { -// output[_out++] = 0; -// } while (--len); -// continue top; -// } -// len -= op - whave; -// do { -// output[_out++] = 0; -// } while (--op > whave); -// if (op === 0) { -// from = _out - dist; -// do { -// output[_out++] = output[from++]; -// } while (--len); -// continue top; -// } -//#endif - } - from = 0; // window index - from_source = s_window; - if (wnext === 0) { /* very common case */ - from += wsize - op; - if (op < len) { /* some from window */ - len -= op; - do { - output[_out++] = s_window[from++]; - } while (--op); - from = _out - dist; /* rest from output */ - from_source = output; - } - } - else if (wnext < op) { /* wrap around window */ - from += wsize + wnext - op; - op -= wnext; - if (op < len) { /* some from end of window */ - len -= op; - do { - output[_out++] = s_window[from++]; - } while (--op); - from = 0; - if (wnext < len) { /* some from start of window */ - op = wnext; - len -= op; - do { - output[_out++] = s_window[from++]; - } while (--op); - from = _out - dist; /* rest from output */ - from_source = output; - } - } - } - else { /* contiguous in window */ - from += wnext - op; - if (op < len) { /* some from window */ - len -= op; - do { - output[_out++] = s_window[from++]; - } while (--op); - from = _out - dist; /* rest from output */ - from_source = output; - } - } - while (len > 2) { - output[_out++] = from_source[from++]; - output[_out++] = from_source[from++]; - output[_out++] = from_source[from++]; - len -= 3; - } - if (len) { - output[_out++] = from_source[from++]; - if (len > 1) { - output[_out++] = from_source[from++]; - } - } - } - else { - from = _out - dist; /* copy direct from output */ - do { /* minimum length is three */ - output[_out++] = output[from++]; - output[_out++] = output[from++]; - output[_out++] = output[from++]; - len -= 3; - } while (len > 2); - if (len) { - output[_out++] = output[from++]; - if (len > 1) { - output[_out++] = output[from++]; - } - } - } - } - else if ((op & 64) === 0) { /* 2nd level distance code */ - here = dcode[(here & 0xffff)/*here.val*/ + (hold & ((1 << op) - 1))]; - continue dodist; - } - else { - strm.msg = 'invalid distance code'; - state.mode = BAD; - break top; - } - - break; // need to emulate goto via "continue" - } - } - else if ((op & 64) === 0) { /* 2nd level length code */ - here = lcode[(here & 0xffff)/*here.val*/ + (hold & ((1 << op) - 1))]; - continue dolen; - } - else if (op & 32) { /* end-of-block */ - //Tracevv((stderr, "inflate: end of block\n")); - state.mode = TYPE; - break top; - } - else { - strm.msg = 'invalid literal/length code'; - state.mode = BAD; - break top; - } - - break; // need to emulate goto via "continue" - } - } while (_in < last && _out < end); - - /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ - len = bits >> 3; - _in -= len; - bits -= len << 3; - hold &= (1 << bits) - 1; - - /* update state and return */ - strm.next_in = _in; - strm.next_out = _out; - strm.avail_in = (_in < last ? 5 + (last - _in) : 5 - (_in - last)); - strm.avail_out = (_out < end ? 257 + (end - _out) : 257 - (_out - end)); - state.hold = hold; - state.bits = bits; - return; -}; |