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-rw-r--r--webclients/novnc/vendor/pako/lib/zlib/inffast.js324
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diff --git a/webclients/novnc/vendor/pako/lib/zlib/inffast.js b/webclients/novnc/vendor/pako/lib/zlib/inffast.js
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+++ b/webclients/novnc/vendor/pako/lib/zlib/inffast.js
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+// 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.
+ */
+export default 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 defailts,
+// 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;
+};
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