diff options
Diffstat (limited to 'zlib/contrib/infback9/infback9.c')
| -rw-r--r-- | zlib/contrib/infback9/infback9.c | 91 |
1 files changed, 50 insertions, 41 deletions
diff --git a/zlib/contrib/infback9/infback9.c b/zlib/contrib/infback9/infback9.c index f5ddde67d..7bbe90ced 100644 --- a/zlib/contrib/infback9/infback9.c +++ b/zlib/contrib/infback9/infback9.c @@ -1,5 +1,5 @@ /* infback9.c -- inflate deflate64 data using a call-back interface - * Copyright (C) 1995-2003 Mark Adler + * Copyright (C) 1995-2008 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -242,7 +242,7 @@ void FAR *out_desc; code const FAR *distcode; /* starting table for distance codes */ unsigned lenbits; /* index bits for lencode */ unsigned distbits; /* index bits for distcode */ - code this; /* current decoding table entry */ + code here; /* current decoding table entry */ code last; /* parent table entry */ unsigned len; /* length to copy for repeats, bits to drop */ int ret; /* return code */ @@ -384,19 +384,19 @@ void FAR *out_desc; state->have = 0; while (state->have < state->nlen + state->ndist) { for (;;) { - this = lencode[BITS(lenbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = lencode[BITS(lenbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if (this.val < 16) { - NEEDBITS(this.bits); - DROPBITS(this.bits); - state->lens[state->have++] = this.val; + if (here.val < 16) { + NEEDBITS(here.bits); + DROPBITS(here.bits); + state->lens[state->have++] = here.val; } else { - if (this.val == 16) { - NEEDBITS(this.bits + 2); - DROPBITS(this.bits); + if (here.val == 16) { + NEEDBITS(here.bits + 2); + DROPBITS(here.bits); if (state->have == 0) { strm->msg = (char *)"invalid bit length repeat"; mode = BAD; @@ -406,16 +406,16 @@ void FAR *out_desc; copy = 3 + BITS(2); DROPBITS(2); } - else if (this.val == 17) { - NEEDBITS(this.bits + 3); - DROPBITS(this.bits); + else if (here.val == 17) { + NEEDBITS(here.bits + 3); + DROPBITS(here.bits); len = 0; copy = 3 + BITS(3); DROPBITS(3); } else { - NEEDBITS(this.bits + 7); - DROPBITS(this.bits); + NEEDBITS(here.bits + 7); + DROPBITS(here.bits); len = 0; copy = 11 + BITS(7); DROPBITS(7); @@ -433,7 +433,16 @@ void FAR *out_desc; /* handle error breaks in while */ if (mode == BAD) break; - /* build code tables */ + /* check for end-of-block code (better have one) */ + if (state->lens[256] == 0) { + strm->msg = (char *)"invalid code -- missing end-of-block"; + mode = BAD; + break; + } + + /* build code tables -- note: do not change the lenbits or distbits + values here (9 and 6) without reading the comments in inftree9.h + concerning the ENOUGH constants, which depend on those values */ state->next = state->codes; lencode = (code const FAR *)(state->next); lenbits = 9; @@ -460,28 +469,28 @@ void FAR *out_desc; case LEN: /* get a literal, length, or end-of-block code */ for (;;) { - this = lencode[BITS(lenbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = lencode[BITS(lenbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if (this.op && (this.op & 0xf0) == 0) { - last = this; + if (here.op && (here.op & 0xf0) == 0) { + last = here; for (;;) { - this = lencode[last.val + + here = lencode[last.val + (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; + if ((unsigned)(last.bits + here.bits) <= bits) break; PULLBYTE(); } DROPBITS(last.bits); } - DROPBITS(this.bits); - length = (unsigned)this.val; + DROPBITS(here.bits); + length = (unsigned)here.val; /* process literal */ - if (this.op == 0) { - Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + if (here.op == 0) { + Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", this.val)); + "inflate: literal 0x%02x\n", here.val)); ROOM(); *put++ = (unsigned char)(length); left--; @@ -490,21 +499,21 @@ void FAR *out_desc; } /* process end of block */ - if (this.op & 32) { + if (here.op & 32) { Tracevv((stderr, "inflate: end of block\n")); mode = TYPE; break; } /* invalid code */ - if (this.op & 64) { + if (here.op & 64) { strm->msg = (char *)"invalid literal/length code"; mode = BAD; break; } /* length code -- get extra bits, if any */ - extra = (unsigned)(this.op) & 31; + extra = (unsigned)(here.op) & 31; if (extra != 0) { NEEDBITS(extra); length += BITS(extra); @@ -514,30 +523,30 @@ void FAR *out_desc; /* get distance code */ for (;;) { - this = distcode[BITS(distbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = distcode[BITS(distbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if ((this.op & 0xf0) == 0) { - last = this; + if ((here.op & 0xf0) == 0) { + last = here; for (;;) { - this = distcode[last.val + + here = distcode[last.val + (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; + if ((unsigned)(last.bits + here.bits) <= bits) break; PULLBYTE(); } DROPBITS(last.bits); } - DROPBITS(this.bits); - if (this.op & 64) { + DROPBITS(here.bits); + if (here.op & 64) { strm->msg = (char *)"invalid distance code"; mode = BAD; break; } - offset = (unsigned)this.val; + offset = (unsigned)here.val; /* get distance extra bits, if any */ - extra = (unsigned)(this.op) & 15; + extra = (unsigned)(here.op) & 15; if (extra != 0) { NEEDBITS(extra); offset += BITS(extra); |