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| #include "zutil.h" |
| #include "inftrees.h" |
| #include "inflate.h" |
| #include "inffast.h" |
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| #ifndef ASMINF |
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| #ifdef POSTINC |
| # define OFF 0 |
| # define PUP(a) *(a)++ |
| #else |
| # define OFF 1 |
| # define PUP(a) *++(a) |
| #endif |
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| void ZLIB_INTERNAL inflate_fast(strm, start) |
| z_streamp strm; |
| unsigned start; |
| { |
| struct inflate_state FAR *state; |
| z_const unsigned char FAR *in; |
| z_const unsigned char FAR *last; |
| unsigned char FAR *out; |
| unsigned char FAR *beg; |
| unsigned char FAR *end; |
| #ifdef INFLATE_STRICT |
| unsigned dmax; |
| #endif |
| unsigned wsize; |
| unsigned whave; |
| unsigned wnext; |
| unsigned char FAR *window; |
| unsigned long hold; |
| unsigned bits; |
| code const FAR *lcode; |
| code const FAR *dcode; |
| unsigned lmask; |
| unsigned dmask; |
| code here; |
| unsigned op; |
| |
| unsigned len; |
| unsigned dist; |
| unsigned char FAR *from; |
| |
| |
| state = (struct inflate_state FAR *)strm->state; |
| in = strm->next_in - OFF; |
| last = in + (strm->avail_in - 5); |
| out = strm->next_out - OFF; |
| 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; |
| window = state->window; |
| hold = state->hold; |
| bits = state->bits; |
| lcode = state->lencode; |
| dcode = state->distcode; |
| lmask = (1U << state->lenbits) - 1; |
| dmask = (1U << state->distbits) - 1; |
| |
| |
| |
| do { |
| if (bits < 15) { |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| } |
| here = lcode[hold & lmask]; |
| dolen: |
| op = (unsigned)(here.bits); |
| hold >>= op; |
| bits -= op; |
| op = (unsigned)(here.op); |
| if (op == 0) { |
| Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? |
| "inflate: literal '%c'\n" : |
| "inflate: literal 0x%02x\n", here.val)); |
| PUP(out) = (unsigned char)(here.val); |
| } |
| else if (op & 16) { |
| len = (unsigned)(here.val); |
| op &= 15; |
| if (op) { |
| if (bits < op) { |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| } |
| len += (unsigned)hold & ((1U << op) - 1); |
| hold >>= op; |
| bits -= op; |
| } |
| Tracevv((stderr, "inflate: length %u\n", len)); |
| if (bits < 15) { |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| } |
| here = dcode[hold & dmask]; |
| dodist: |
| op = (unsigned)(here.bits); |
| hold >>= op; |
| bits -= op; |
| op = (unsigned)(here.op); |
| if (op & 16) { |
| dist = (unsigned)(here.val); |
| op &= 15; |
| if (bits < op) { |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| if (bits < op) { |
| hold += (unsigned long)(PUP(in)) << bits; |
| bits += 8; |
| } |
| } |
| dist += (unsigned)hold & ((1U << op) - 1); |
| #ifdef INFLATE_STRICT |
| if (dist > dmax) { |
| strm->msg = (char *)"invalid distance too far back"; |
| state->mode = BAD; |
| break; |
| } |
| #endif |
| hold >>= op; |
| bits -= op; |
| Tracevv((stderr, "inflate: distance %u\n", dist)); |
| op = (unsigned)(out - beg); |
| if (dist > op) { |
| op = dist - op; |
| if (op > whave) { |
| 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 (wnext == 0) { |
| from += wsize - op; |
| if (op < len) { |
| len -= op; |
| do { |
| PUP(out) = PUP(from); |
| } while (--op); |
| from = out - dist; |
| } |
| } |
| else if (wnext < op) { |
| from += wsize + wnext - op; |
| op -= wnext; |
| if (op < len) { |
| len -= op; |
| do { |
| PUP(out) = PUP(from); |
| } while (--op); |
| from = window - OFF; |
| if (wnext < len) { |
| op = wnext; |
| len -= op; |
| do { |
| PUP(out) = PUP(from); |
| } while (--op); |
| from = out - dist; |
| } |
| } |
| } |
| else { |
| from += wnext - op; |
| if (op < len) { |
| len -= op; |
| do { |
| PUP(out) = PUP(from); |
| } while (--op); |
| from = out - dist; |
| } |
| } |
| while (len > 2) { |
| PUP(out) = PUP(from); |
| PUP(out) = PUP(from); |
| PUP(out) = PUP(from); |
| len -= 3; |
| } |
| if (len) { |
| PUP(out) = PUP(from); |
| if (len > 1) |
| PUP(out) = PUP(from); |
| } |
| } |
| else { |
| from = out - dist; |
| do { |
| PUP(out) = PUP(from); |
| PUP(out) = PUP(from); |
| PUP(out) = PUP(from); |
| len -= 3; |
| } while (len > 2); |
| if (len) { |
| PUP(out) = PUP(from); |
| if (len > 1) |
| PUP(out) = PUP(from); |
| } |
| } |
| } |
| else if ((op & 64) == 0) { |
| here = dcode[here.val + (hold & ((1U << op) - 1))]; |
| goto dodist; |
| } |
| else { |
| strm->msg = (char *)"invalid distance code"; |
| state->mode = BAD; |
| break; |
| } |
| } |
| else if ((op & 64) == 0) { |
| here = lcode[here.val + (hold & ((1U << op) - 1))]; |
| goto dolen; |
| } |
| else if (op & 32) { |
| Tracevv((stderr, "inflate: end of block\n")); |
| state->mode = TYPE; |
| break; |
| } |
| else { |
| strm->msg = (char *)"invalid literal/length code"; |
| state->mode = BAD; |
| break; |
| } |
| } while (in < last && out < end); |
| |
| |
| len = bits >> 3; |
| in -= len; |
| bits -= len << 3; |
| hold &= (1U << bits) - 1; |
| |
| |
| strm->next_in = in + OFF; |
| strm->next_out = out + OFF; |
| strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last)); |
| strm->avail_out = (unsigned)(out < end ? |
| 257 + (end - out) : 257 - (out - end)); |
| state->hold = hold; |
| state->bits = bits; |
| return; |
| } |
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| #endif /* !ASMINF */ |