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author | Björn Gustavsson <[email protected]> | 2014-01-09 12:26:18 +0100 |
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committer | Björn Gustavsson <[email protected]> | 2014-01-14 09:30:34 +0100 |
commit | 9205b6671892e7516e8571e4ecf19bfa2ade1130 (patch) | |
tree | e2027206adefa16bdd3a323824986ef0719b4806 /erts/emulator/zlib/inffast.c | |
parent | 069f9ec3dfd7a4dc17973e22dc271d40ebe11467 (diff) | |
download | otp-9205b6671892e7516e8571e4ecf19bfa2ade1130.tar.gz otp-9205b6671892e7516e8571e4ecf19bfa2ade1130.tar.bz2 otp-9205b6671892e7516e8571e4ecf19bfa2ade1130.zip |
Update zlib to 1.2.8
Diffstat (limited to 'erts/emulator/zlib/inffast.c')
-rw-r--r-- | erts/emulator/zlib/inffast.c | 86 |
1 files changed, 53 insertions, 33 deletions
diff --git a/erts/emulator/zlib/inffast.c b/erts/emulator/zlib/inffast.c index eb81884888..5187743fde 100644 --- a/erts/emulator/zlib/inffast.c +++ b/erts/emulator/zlib/inffast.c @@ -1,10 +1,8 @@ /* inffast.c -- fast decoding - * Copyright (C) 1995-2004 Mark Adler + * Copyright (C) 1995-2008, 2010, 2013 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ -/* %ExternalCopyright% */ - #ifdef HAVE_CONFIG_H # include "config.h" #endif @@ -69,13 +67,13 @@ requires strm->avail_out >= 258 for each loop to avoid checking for output space. */ -void inflate_fast(strm, start) +void ZLIB_INTERNAL inflate_fast(strm, start) z_streamp strm; unsigned start; /* inflate()'s starting value for strm->avail_out */ { struct inflate_state FAR *state; - unsigned char FAR *in; /* local strm->next_in */ - unsigned char FAR *last; /* while in < last, enough input available */ + z_const unsigned char FAR *in; /* local strm->next_in */ + z_const unsigned char FAR *last; /* have enough input while in < last */ unsigned char FAR *out; /* local strm->next_out */ unsigned char FAR *beg; /* inflate()'s initial strm->next_out */ unsigned char FAR *end; /* while out < end, enough space available */ @@ -84,7 +82,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ #endif unsigned wsize; /* window size or zero if not using window */ unsigned whave; /* valid bytes in the window */ - unsigned write; /* window write index */ + unsigned wnext; /* window write index */ unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ unsigned long hold; /* local strm->hold */ unsigned bits; /* local strm->bits */ @@ -92,7 +90,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ code const FAR *dcode; /* local strm->distcode */ unsigned lmask; /* mask for first level of length codes */ unsigned dmask; /* mask for first level of distance codes */ - code this; /* retrieved table entry */ + code here; /* retrieved table entry */ unsigned op; /* code bits, operation, extra bits, or */ /* window position, window bytes to copy */ unsigned len; /* match length, unused bytes */ @@ -111,7 +109,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ #endif wsize = state->wsize; whave = state->whave; - write = state->write; + wnext = state->wnext; window = state->window; hold = state->hold; bits = state->bits; @@ -129,20 +127,20 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ hold += (unsigned long)(PUP(in)) << bits; bits += 8; } - this = lcode[hold & lmask]; + here = lcode[hold & lmask]; dolen: - op = (unsigned)(this.bits); + op = (unsigned)(here.bits); hold >>= op; bits -= op; - op = (unsigned)(this.op); + op = (unsigned)(here.op); if (op == 0) { /* literal */ - Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", this.val)); - PUP(out) = (unsigned char)(this.val); + "inflate: literal 0x%02x\n", here.val)); + PUP(out) = (unsigned char)(here.val); } else if (op & 16) { /* length base */ - len = (unsigned)(this.val); + len = (unsigned)(here.val); op &= 15; /* number of extra bits */ if (op) { if (bits < op) { @@ -160,14 +158,14 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ hold += (unsigned long)(PUP(in)) << bits; bits += 8; } - this = dcode[hold & dmask]; + here = dcode[hold & dmask]; dodist: - op = (unsigned)(this.bits); + op = (unsigned)(here.bits); hold >>= op; bits -= op; - op = (unsigned)(this.op); + op = (unsigned)(here.op); if (op & 16) { /* distance base */ - dist = (unsigned)(this.val); + dist = (unsigned)(here.val); op &= 15; /* number of extra bits */ if (bits < op) { hold += (unsigned long)(PUP(in)) << bits; @@ -192,12 +190,34 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ if (dist > op) { /* see if copy from window */ op = dist - op; /* distance back in window */ if (op > whave) { - strm->msg = (char *)"invalid distance too far back"; - state->mode = BAD; - break; + if (state->sane) { + strm->msg = + (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR + if (len <= op - whave) { + do { + PUP(out) = 0; + } while (--len); + continue; + } + len -= op - whave; + do { + PUP(out) = 0; + } while (--op > whave); + if (op == 0) { + from = out - dist; + do { + PUP(out) = PUP(from); + } while (--len); + continue; + } +#endif } from = window - OFF; - if (write == 0) { /* very common case */ + if (wnext == 0) { /* very common case */ from += wsize - op; if (op < len) { /* some from window */ len -= op; @@ -207,17 +227,17 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ from = out - dist; /* rest from output */ } } - else if (write < op) { /* wrap around window */ - from += wsize + write - op; - op -= write; + else if (wnext < op) { /* wrap around window */ + from += wsize + wnext - op; + op -= wnext; if (op < len) { /* some from end of window */ len -= op; do { PUP(out) = PUP(from); } while (--op); from = window - OFF; - if (write < len) { /* some from start of window */ - op = write; + if (wnext < len) { /* some from start of window */ + op = wnext; len -= op; do { PUP(out) = PUP(from); @@ -227,7 +247,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ } } else { /* contiguous in window */ - from += write - op; + from += wnext - op; if (op < len) { /* some from window */ len -= op; do { @@ -264,7 +284,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ } } else if ((op & 64) == 0) { /* 2nd level distance code */ - this = dcode[this.val + (hold & ((1U << op) - 1))]; + here = dcode[here.val + (hold & ((1U << op) - 1))]; goto dodist; } else { @@ -274,7 +294,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ } } else if ((op & 64) == 0) { /* 2nd level length code */ - this = lcode[this.val + (hold & ((1U << op) - 1))]; + here = lcode[here.val + (hold & ((1U << op) - 1))]; goto dolen; } else if (op & 32) { /* end-of-block */ @@ -310,7 +330,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */ inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe): - Using bit fields for code structure - Different op definition to avoid & for extra bits (do & for table bits) - - Three separate decoding do-loops for direct, window, and write == 0 + - Three separate decoding do-loops for direct, window, and wnext == 0 - Special case for distance > 1 copies to do overlapped load and store copy - Explicit branch predictions (based on measured branch probabilities) - Deferring match copy and interspersed it with decoding subsequent codes |