| From a3719bd5f937566faab554c9596e7984a37ec5c8 Mon Sep 17 00:00:00 2001 |
| From: Adenilson Cavalcanti <adenilson.cavalcanti@arm.com> |
| Date: Thu, 28 Sep 2017 12:31:26 -0700 |
| Subject: [PATCH] zlib: inflate using wider loads and stores |
| |
| In inflate_fast() the output pointer always has plenty of room to write. |
| This means that so long as the target is capable, wide un-aligned |
| loads and stores can be used to transfer several bytes at once. |
| |
| When the reference distance is too short simply unroll the data a |
| little to increase the distance. Patch by Simon Hosie. |
| |
| PNG decoding performance gains should be around 30-33%. |
| |
| This also includes the fix reported in madler/zlib#245. |
| --- |
| third_party/zlib/BUILD.gn | 19 + |
| third_party/zlib/contrib/arm/chunkcopy.h | 297 ++++++ |
| third_party/zlib/contrib/arm/inffast.c | 307 ++++++ |
| third_party/zlib/contrib/arm/inflate.c | 1572 ++++++++++++++++++++++++++++++ |
| 4 files changed, 2195 insertions(+) |
| create mode 100644 third_party/zlib/contrib/arm/chunkcopy.h |
| create mode 100644 third_party/zlib/contrib/arm/inffast.c |
| create mode 100644 third_party/zlib/contrib/arm/inflate.c |
| |
| diff --git a/third_party/zlib/BUILD.gn b/third_party/zlib/BUILD.gn |
| index 4b4db15..027a38c 100644 |
| --- a/third_party/zlib/BUILD.gn |
| +++ b/third_party/zlib/BUILD.gn |
| @@ -2,6 +2,10 @@ |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| +if (current_cpu == "arm" || current_cpu == "arm64") { |
| + import("//build/config/arm.gni") |
| +} |
| + |
| config("zlib_config") { |
| include_dirs = [ "." ] |
| } |
| @@ -71,6 +75,21 @@ static_library("zlib") { |
| "zutil.h", |
| ] |
| |
| + if (current_cpu == "arm" || current_cpu == "arm64") { |
| + if (arm_use_neon) { |
| + # TODO: handle InflateBack case, see crbug.com/769880. |
| + sources -= [ |
| + "inffast.c", |
| + "inflate.c", |
| + ] |
| + sources += [ |
| + "contrib/arm/chunkcopy.h", |
| + "contrib/arm/inffast.c", |
| + "contrib/arm/inflate.c", |
| + ] |
| + } |
| + } |
| + |
| if (!is_ios && (current_cpu == "x86" || current_cpu == "x64")) { |
| sources += [ "x86.c" ] |
| } |
| diff --git a/third_party/zlib/contrib/arm/chunkcopy.h b/third_party/zlib/contrib/arm/chunkcopy.h |
| new file mode 100644 |
| index 0000000..bc8a77d |
| --- /dev/null |
| +++ b/third_party/zlib/contrib/arm/chunkcopy.h |
| @@ -0,0 +1,297 @@ |
| +/* chunkcopy.h -- fast copies and sets |
| + * Copyright (C) 2017 ARM, Inc. |
| + * For conditions of distribution and use, see copyright notice in zlib.h |
| + */ |
| + |
| +#ifndef CHUNKCOPY_H |
| +#define CHUNKCOPY_H |
| + |
| +#include <arm_neon.h> |
| +#include "zutil.h" |
| + |
| +#if __STDC_VERSION__ >= 199901L |
| +#define Z_RESTRICT restrict |
| +#else |
| +#define Z_RESTRICT |
| +#endif |
| + |
| +typedef uint8x16_t chunkcopy_chunk_t; |
| +#define CHUNKCOPY_CHUNK_SIZE sizeof(chunkcopy_chunk_t) |
| + |
| +/* |
| + Ask the compiler to perform a wide, unaligned load with an machine |
| + instruction appropriate for the chunkcopy_chunk_t type. |
| + */ |
| +static inline chunkcopy_chunk_t loadchunk(const unsigned char FAR* s) { |
| + chunkcopy_chunk_t c; |
| + __builtin_memcpy(&c, s, sizeof(c)); |
| + return c; |
| +} |
| + |
| +/* |
| + Ask the compiler to perform a wide, unaligned store with an machine |
| + instruction appropriate for the chunkcopy_chunk_t type. |
| + */ |
| +static inline void storechunk(unsigned char FAR* d, chunkcopy_chunk_t c) { |
| + __builtin_memcpy(d, &c, sizeof(c)); |
| +} |
| + |
| +/* |
| + Perform a memcpy-like operation, but assume that length is non-zero and that |
| + it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE bytes of output even if |
| + the length is shorter than this. |
| + |
| + It also guarantees that it will properly unroll the data if the distance |
| + between `out` and `from` is at least CHUNKCOPY_CHUNK_SIZE, which we rely on |
| + in chunkcopy_relaxed(). |
| + |
| + Aside from better memory bus utilisation, this means that short copies |
| + (CHUNKCOPY_CHUNK_SIZE bytes or fewer) will fall straight through the loop |
| + without iteration, which will hopefully make the branch prediction more |
| + reliable. |
| + */ |
| +static inline unsigned char FAR* chunkcopy_core(unsigned char FAR* out, |
| + const unsigned char FAR* from, |
| + unsigned len) { |
| + int bump = (--len % CHUNKCOPY_CHUNK_SIZE) + 1; |
| + storechunk(out, loadchunk(from)); |
| + out += bump; |
| + from += bump; |
| + len /= CHUNKCOPY_CHUNK_SIZE; |
| + while (len-- > 0) { |
| + storechunk(out, loadchunk(from)); |
| + out += CHUNKCOPY_CHUNK_SIZE; |
| + from += CHUNKCOPY_CHUNK_SIZE; |
| + } |
| + return out; |
| +} |
| + |
| +/* |
| + Like chunkcopy_core, but avoid writing beyond of legal output. |
| + |
| + Accepts an additional pointer to the end of safe output. A generic safe |
| + copy would use (out + len), but it's normally the case that the end of the |
| + output buffer is beyond the end of the current copy, and this can still be |
| + exploited. |
| + */ |
| +static inline unsigned char FAR* chunkcopy_core_safe( |
| + unsigned char FAR* out, |
| + const unsigned char FAR* from, |
| + unsigned len, |
| + unsigned char FAR* limit) { |
| + Assert(out + len <= limit, "chunk copy exceeds safety limit"); |
| + if (limit - out < CHUNKCOPY_CHUNK_SIZE) { |
| + const unsigned char FAR* Z_RESTRICT rfrom = from; |
| + if (len & 8) { |
| + __builtin_memcpy(out, rfrom, 8); |
| + out += 8; |
| + rfrom += 8; |
| + } |
| + if (len & 4) { |
| + __builtin_memcpy(out, rfrom, 4); |
| + out += 4; |
| + rfrom += 4; |
| + } |
| + if (len & 2) { |
| + __builtin_memcpy(out, rfrom, 2); |
| + out += 2; |
| + rfrom += 2; |
| + } |
| + if (len & 1) { |
| + *out++ = *rfrom++; |
| + } |
| + return out; |
| + } |
| + return chunkcopy_core(out, from, len); |
| +} |
| + |
| +/* |
| + Perform short copies until distance can be rewritten as being at least |
| + CHUNKCOPY_CHUNK_SIZE. |
| + |
| + This assumes that it's OK to overwrite at least the first |
| + 2*CHUNKCOPY_CHUNK_SIZE bytes of output even if the copy is shorter than |
| + this. This assumption holds within inflate_fast() which starts every |
| + iteration with at least 258 bytes of output space available (258 being the |
| + maximum length output from a single token; see inffast.c). |
| + */ |
| +static inline unsigned char FAR* chunkunroll_relaxed(unsigned char FAR* out, |
| + unsigned FAR* dist, |
| + unsigned FAR* len) { |
| + const unsigned char FAR* from = out - *dist; |
| + while (*dist < *len && *dist < CHUNKCOPY_CHUNK_SIZE) { |
| + storechunk(out, loadchunk(from)); |
| + out += *dist; |
| + *len -= *dist; |
| + *dist += *dist; |
| + } |
| + return out; |
| +} |
| + |
| +static inline uint8x16_t chunkset_vld1q_dup_u8x8( |
| + const unsigned char FAR* Z_RESTRICT from) { |
| +#if defined(__clang__) || defined(__aarch64__) |
| + return vreinterpretq_u8_u64(vld1q_dup_u64((void*)from)); |
| +#else |
| + /* 32-bit GCC uses an alignment hint for vld1q_dup_u64, even when given a |
| + * void pointer, so here's an alternate implementation. |
| + */ |
| + uint8x8_t h = vld1_u8(from); |
| + return vcombine_u8(h, h); |
| +#endif |
| +} |
| + |
| +/* |
| + Perform an overlapping copy which behaves as a memset() operation, but |
| + supporting periods other than one, and assume that length is non-zero and |
| + that it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE*3 bytes of output |
| + even if the length is shorter than this. |
| + */ |
| +static inline unsigned char FAR* chunkset_core(unsigned char FAR* out, |
| + unsigned period, |
| + unsigned len) { |
| + uint8x16_t f; |
| + int bump = ((len - 1) % sizeof(f)) + 1; |
| + |
| + switch (period) { |
| + case 1: |
| + f = vld1q_dup_u8(out - 1); |
| + vst1q_u8(out, f); |
| + out += bump; |
| + len -= bump; |
| + while (len > 0) { |
| + vst1q_u8(out, f); |
| + out += sizeof(f); |
| + len -= sizeof(f); |
| + } |
| + return out; |
| + case 2: |
| + f = vreinterpretq_u8_u16(vld1q_dup_u16((void*)(out - 2))); |
| + vst1q_u8(out, f); |
| + out += bump; |
| + len -= bump; |
| + if (len > 0) { |
| + f = vreinterpretq_u8_u16(vld1q_dup_u16((void*)(out - 2))); |
| + do { |
| + vst1q_u8(out, f); |
| + out += sizeof(f); |
| + len -= sizeof(f); |
| + } while (len > 0); |
| + } |
| + return out; |
| + case 4: |
| + f = vreinterpretq_u8_u32(vld1q_dup_u32((void*)(out - 4))); |
| + vst1q_u8(out, f); |
| + out += bump; |
| + len -= bump; |
| + if (len > 0) { |
| + f = vreinterpretq_u8_u32(vld1q_dup_u32((void*)(out - 4))); |
| + do { |
| + vst1q_u8(out, f); |
| + out += sizeof(f); |
| + len -= sizeof(f); |
| + } while (len > 0); |
| + } |
| + return out; |
| + case 8: |
| + f = chunkset_vld1q_dup_u8x8(out - 8); |
| + vst1q_u8(out, f); |
| + out += bump; |
| + len -= bump; |
| + if (len > 0) { |
| + f = chunkset_vld1q_dup_u8x8(out - 8); |
| + do { |
| + vst1q_u8(out, f); |
| + out += sizeof(f); |
| + len -= sizeof(f); |
| + } while (len > 0); |
| + } |
| + return out; |
| + } |
| + out = chunkunroll_relaxed(out, &period, &len); |
| + return chunkcopy_core(out, out - period, len); |
| +} |
| + |
| +/* |
| + Perform a memcpy-like operation, but assume that length is non-zero and that |
| + it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE bytes of output even if |
| + the length is shorter than this. |
| + |
| + Unlike chunkcopy_core() above, no guarantee is made regarding the behaviour |
| + of overlapping buffers, regardless of the distance between the pointers. |
| + This is reflected in the `restrict`-qualified pointers, allowing the |
| + compiler to reorder loads and stores. |
| + */ |
| +static inline unsigned char FAR* chunkcopy_relaxed( |
| + unsigned char FAR* Z_RESTRICT out, |
| + const unsigned char FAR* Z_RESTRICT from, |
| + unsigned len) { |
| + return chunkcopy_core(out, from, len); |
| +} |
| + |
| +/* |
| + Like chunkcopy_relaxed, but avoid writing beyond of legal output. |
| + |
| + Unlike chunkcopy_core_safe() above, no guarantee is made regarding the |
| + behaviour of overlapping buffers, regardless of the distance between the |
| + pointers. This is reflected in the `restrict`-qualified pointers, allowing |
| + the compiler to reorder loads and stores. |
| + |
| + Accepts an additional pointer to the end of safe output. A generic safe |
| + copy would use (out + len), but it's normally the case that the end of the |
| + output buffer is beyond the end of the current copy, and this can still be |
| + exploited. |
| + */ |
| +static inline unsigned char FAR* chunkcopy_safe( |
| + unsigned char FAR* out, |
| + const unsigned char FAR* Z_RESTRICT from, |
| + unsigned len, |
| + unsigned char FAR* limit) { |
| + Assert(out + len <= limit, "chunk copy exceeds safety limit"); |
| + return chunkcopy_core_safe(out, from, len, limit); |
| +} |
| + |
| +/* |
| + Perform chunky copy within the same buffer, where the source and destination |
| + may potentially overlap. |
| + |
| + Assumes that len > 0 on entry, and that it's safe to write at least |
| + CHUNKCOPY_CHUNK_SIZE*3 bytes to the output. |
| + */ |
| +static inline unsigned char FAR* |
| +chunkcopy_lapped_relaxed(unsigned char FAR* out, unsigned dist, unsigned len) { |
| + if (dist < len && dist < CHUNKCOPY_CHUNK_SIZE) { |
| + return chunkset_core(out, dist, len); |
| + } |
| + return chunkcopy_core(out, out - dist, len); |
| +} |
| + |
| +/* |
| + Behave like chunkcopy_lapped_relaxed, but avoid writing beyond of legal |
| + output. |
| + |
| + Accepts an additional pointer to the end of safe output. A generic safe |
| + copy would use (out + len), but it's normally the case that the end of the |
| + output buffer is beyond the end of the current copy, and this can still be |
| + exploited. |
| + */ |
| +static inline unsigned char FAR* chunkcopy_lapped_safe( |
| + unsigned char FAR* out, |
| + unsigned dist, |
| + unsigned len, |
| + unsigned char FAR* limit) { |
| + Assert(out + len <= limit, "chunk copy exceeds safety limit"); |
| + if (limit - out < CHUNKCOPY_CHUNK_SIZE * 3) { |
| + /* TODO: try harder to optimise this */ |
| + while (len-- > 0) { |
| + *out = *(out - dist); |
| + out++; |
| + } |
| + return out; |
| + } |
| + return chunkcopy_lapped_relaxed(out, dist, len); |
| +} |
| + |
| +#undef Z_RESTRICT |
| + |
| +#endif /* CHUNKCOPY_H */ |
| diff --git a/third_party/zlib/contrib/arm/inffast.c b/third_party/zlib/contrib/arm/inffast.c |
| new file mode 100644 |
| index 0000000..f7f5007 |
| --- /dev/null |
| +++ b/third_party/zlib/contrib/arm/inffast.c |
| @@ -0,0 +1,307 @@ |
| +/* inffast.c -- fast decoding |
| + * Copyright (C) 1995-2017 Mark Adler |
| + * For conditions of distribution and use, see copyright notice in zlib.h |
| + */ |
| + |
| +#include "zutil.h" |
| +#include "inftrees.h" |
| +#include "inflate.h" |
| +#include "inffast.h" |
| +#include "chunkcopy.h" |
| + |
| +#ifdef ASMINF |
| +# pragma message("Assembler code may have bugs -- use at your own risk") |
| +#else |
| + |
| +/* |
| + 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. |
| + */ |
| +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; |
| + 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 */ |
| + unsigned char FAR *limit; /* safety limit for chunky copies */ |
| +#ifdef INFLATE_STRICT |
| + unsigned dmax; /* maximum distance from zlib header */ |
| +#endif |
| + unsigned wsize; /* window size or zero if not using window */ |
| + unsigned whave; /* valid bytes in the window */ |
| + 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 */ |
| + code const FAR *lcode; /* local strm->lencode */ |
| + 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 here; /* retrieved table entry */ |
| + unsigned op; /* code bits, operation, extra bits, or */ |
| + /* window position, window bytes to copy */ |
| + unsigned len; /* match length, unused bytes */ |
| + unsigned dist; /* match distance */ |
| + unsigned char FAR *from; /* where to copy match from */ |
| + |
| + /* copy state to local variables */ |
| + state = (struct inflate_state FAR *)strm->state; |
| + in = strm->next_in; |
| + last = in + (strm->avail_in - 5); |
| + out = strm->next_out; |
| + beg = out - (start - strm->avail_out); |
| + end = out + (strm->avail_out - 257); |
| + limit = out + strm->avail_out; |
| +#ifdef INFLATE_STRICT |
| + dmax = state->dmax; |
| +#endif |
| + wsize = state->wsize; |
| + whave = state->whave; |
| + wnext = (state->wnext == 0 && whave >= wsize) ? wsize : 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; |
| + |
| + /* decode literals and length/distances until end-of-block or not enough |
| + input data or output space */ |
| + do { |
| + if (bits < 15) { |
| + hold += (unsigned long)(*in++) << bits; |
| + bits += 8; |
| + hold += (unsigned long)(*in++) << bits; |
| + bits += 8; |
| + } |
| + here = lcode[hold & lmask]; |
| + dolen: |
| + op = (unsigned)(here.bits); |
| + hold >>= op; |
| + bits -= op; |
| + op = (unsigned)(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)); |
| + *out++ = (unsigned char)(here.val); |
| + } |
| + else if (op & 16) { /* length base */ |
| + len = (unsigned)(here.val); |
| + op &= 15; /* number of extra bits */ |
| + if (op) { |
| + if (bits < op) { |
| + hold += (unsigned long)(*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)(*in++) << bits; |
| + bits += 8; |
| + hold += (unsigned long)(*in++) << bits; |
| + bits += 8; |
| + } |
| + here = dcode[hold & dmask]; |
| + dodist: |
| + op = (unsigned)(here.bits); |
| + hold >>= op; |
| + bits -= op; |
| + op = (unsigned)(here.op); |
| + if (op & 16) { /* distance base */ |
| + dist = (unsigned)(here.val); |
| + op &= 15; /* number of extra bits */ |
| + if (bits < op) { |
| + hold += (unsigned long)(*in++) << bits; |
| + bits += 8; |
| + if (bits < op) { |
| + hold += (unsigned long)(*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); /* 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 = |
| + (char *)"invalid distance too far back"; |
| + state->mode = BAD; |
| + break; |
| + } |
| +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR |
| + if (len <= op - whave) { |
| + do { |
| + *out++ = 0; |
| + } while (--len); |
| + continue; |
| + } |
| + len -= op - whave; |
| + do { |
| + *out++ = 0; |
| + } while (--op > whave); |
| + if (op == 0) { |
| + from = out - dist; |
| + do { |
| + *out++ = *from++; |
| + } while (--len); |
| + continue; |
| + } |
| +#endif |
| + } |
| + from = window; |
| + if (wnext >= op) { /* contiguous in window */ |
| + from += wnext - op; |
| + } |
| + else { /* wrap around window */ |
| + op -= wnext; |
| + from += wsize - op; |
| + if (op < len) { /* some from end of window */ |
| + len -= op; |
| + out = chunkcopy_safe(out, from, op, limit); |
| + from = window; /* more from start of window */ |
| + op = wnext; |
| + /* This (rare) case can create a situation where |
| + the first chunkcopy below must be checked. |
| + */ |
| + } |
| + } |
| + if (op < len) { /* still need some from output */ |
| + out = chunkcopy_safe(out, from, op, limit); |
| + len -= op; |
| + /* When dist is small the amount of data that can be |
| + copied from the window is also small, and progress |
| + towards the dangerous end of the output buffer is |
| + also small. This means that for trivial memsets and |
| + for chunkunroll_relaxed() a safety check is |
| + unnecessary. However, these conditions may not be |
| + entered at all, and in that case it's possible that |
| + the main copy is near the end. |
| + */ |
| + out = chunkunroll_relaxed(out, &dist, &len); |
| + out = chunkcopy_safe(out, out - dist, len, limit); |
| + } else { |
| + /* from points to window, so there is no risk of |
| + overlapping pointers requiring memset-like behaviour |
| + */ |
| + out = chunkcopy_safe(out, from, len, limit); |
| + } |
| + } |
| + else { |
| + /* Whole reference is in range of current output. No |
| + range checks are necessary because we start with room |
| + for at least 258 bytes of output, so unroll and roundoff |
| + operations can write beyond `out+len` so long as they |
| + stay within 258 bytes of `out`. |
| + */ |
| + out = chunkcopy_lapped_relaxed(out, dist, len); |
| + } |
| + } |
| + else if ((op & 64) == 0) { /* 2nd level distance code */ |
| + 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) { /* 2nd level length code */ |
| + here = lcode[here.val + (hold & ((1U << op) - 1))]; |
| + goto dolen; |
| + } |
| + else if (op & 32) { /* end-of-block */ |
| + 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); |
| + |
| + /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ |
| + len = bits >> 3; |
| + in -= len; |
| + bits -= len << 3; |
| + hold &= (1U << bits) - 1; |
| + |
| + /* update state and return */ |
| + strm->next_in = in; |
| + strm->next_out = out; |
| + 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; |
| +} |
| + |
| +/* |
| + 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 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 |
| + - Swapping literal/length else |
| + - Swapping window/direct else |
| + - Larger unrolled copy loops (three is about right) |
| + - Moving len -= 3 statement into middle of loop |
| + */ |
| + |
| +#endif /* !ASMINF */ |
| diff --git a/third_party/zlib/contrib/arm/inflate.c b/third_party/zlib/contrib/arm/inflate.c |
| new file mode 100644 |
| index 0000000..23e95f1 |
| --- /dev/null |
| +++ b/third_party/zlib/contrib/arm/inflate.c |
| @@ -0,0 +1,1572 @@ |
| +/* inflate.c -- zlib decompression |
| + * Copyright (C) 1995-2016 Mark Adler |
| + * For conditions of distribution and use, see copyright notice in zlib.h |
| + */ |
| + |
| +/* |
| + * Change history: |
| + * |
| + * 1.2.beta0 24 Nov 2002 |
| + * - First version -- complete rewrite of inflate to simplify code, avoid |
| + * creation of window when not needed, minimize use of window when it is |
| + * needed, make inffast.c even faster, implement gzip decoding, and to |
| + * improve code readability and style over the previous zlib inflate code |
| + * |
| + * 1.2.beta1 25 Nov 2002 |
| + * - Use pointers for available input and output checking in inffast.c |
| + * - Remove input and output counters in inffast.c |
| + * - Change inffast.c entry and loop from avail_in >= 7 to >= 6 |
| + * - Remove unnecessary second byte pull from length extra in inffast.c |
| + * - Unroll direct copy to three copies per loop in inffast.c |
| + * |
| + * 1.2.beta2 4 Dec 2002 |
| + * - Change external routine names to reduce potential conflicts |
| + * - Correct filename to inffixed.h for fixed tables in inflate.c |
| + * - Make hbuf[] unsigned char to match parameter type in inflate.c |
| + * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset) |
| + * to avoid negation problem on Alphas (64 bit) in inflate.c |
| + * |
| + * 1.2.beta3 22 Dec 2002 |
| + * - Add comments on state->bits assertion in inffast.c |
| + * - Add comments on op field in inftrees.h |
| + * - Fix bug in reuse of allocated window after inflateReset() |
| + * - Remove bit fields--back to byte structure for speed |
| + * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths |
| + * - Change post-increments to pre-increments in inflate_fast(), PPC biased? |
| + * - Add compile time option, POSTINC, to use post-increments instead (Intel?) |
| + * - Make MATCH copy in inflate() much faster for when inflate_fast() not used |
| + * - Use local copies of stream next and avail values, as well as local bit |
| + * buffer and bit count in inflate()--for speed when inflate_fast() not used |
| + * |
| + * 1.2.beta4 1 Jan 2003 |
| + * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings |
| + * - Move a comment on output buffer sizes from inffast.c to inflate.c |
| + * - Add comments in inffast.c to introduce the inflate_fast() routine |
| + * - Rearrange window copies in inflate_fast() for speed and simplification |
| + * - Unroll last copy for window match in inflate_fast() |
| + * - Use local copies of window variables in inflate_fast() for speed |
| + * - Pull out common wnext == 0 case for speed in inflate_fast() |
| + * - Make op and len in inflate_fast() unsigned for consistency |
| + * - Add FAR to lcode and dcode declarations in inflate_fast() |
| + * - Simplified bad distance check in inflate_fast() |
| + * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new |
| + * source file infback.c to provide a call-back interface to inflate for |
| + * programs like gzip and unzip -- uses window as output buffer to avoid |
| + * window copying |
| + * |
| + * 1.2.beta5 1 Jan 2003 |
| + * - Improved inflateBack() interface to allow the caller to provide initial |
| + * input in strm. |
| + * - Fixed stored blocks bug in inflateBack() |
| + * |
| + * 1.2.beta6 4 Jan 2003 |
| + * - Added comments in inffast.c on effectiveness of POSTINC |
| + * - Typecasting all around to reduce compiler warnings |
| + * - Changed loops from while (1) or do {} while (1) to for (;;), again to |
| + * make compilers happy |
| + * - Changed type of window in inflateBackInit() to unsigned char * |
| + * |
| + * 1.2.beta7 27 Jan 2003 |
| + * - Changed many types to unsigned or unsigned short to avoid warnings |
| + * - Added inflateCopy() function |
| + * |
| + * 1.2.0 9 Mar 2003 |
| + * - Changed inflateBack() interface to provide separate opaque descriptors |
| + * for the in() and out() functions |
| + * - Changed inflateBack() argument and in_func typedef to swap the length |
| + * and buffer address return values for the input function |
| + * - Check next_in and next_out for Z_NULL on entry to inflate() |
| + * |
| + * The history for versions after 1.2.0 are in ChangeLog in zlib distribution. |
| + */ |
| + |
| +#include "zutil.h" |
| +#include "inftrees.h" |
| +#include "inflate.h" |
| +#include "inffast.h" |
| +#include "contrib/arm/chunkcopy.h" |
| + |
| +#ifdef MAKEFIXED |
| +# ifndef BUILDFIXED |
| +# define BUILDFIXED |
| +# endif |
| +#endif |
| + |
| +/* function prototypes */ |
| +local int inflateStateCheck OF((z_streamp strm)); |
| +local void fixedtables OF((struct inflate_state FAR *state)); |
| +local int updatewindow OF((z_streamp strm, const unsigned char FAR *end, |
| + unsigned copy)); |
| +#ifdef BUILDFIXED |
| + void makefixed OF((void)); |
| +#endif |
| +local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf, |
| + unsigned len)); |
| + |
| +local int inflateStateCheck(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + if (strm == Z_NULL || |
| + strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) |
| + return 1; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (state == Z_NULL || state->strm != strm || |
| + state->mode < HEAD || state->mode > SYNC) |
| + return 1; |
| + return 0; |
| +} |
| + |
| +int ZEXPORT inflateResetKeep(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + strm->total_in = strm->total_out = state->total = 0; |
| + strm->msg = Z_NULL; |
| + if (state->wrap) /* to support ill-conceived Java test suite */ |
| + strm->adler = state->wrap & 1; |
| + state->mode = HEAD; |
| + state->last = 0; |
| + state->havedict = 0; |
| + state->dmax = 32768U; |
| + state->head = Z_NULL; |
| + state->hold = 0; |
| + state->bits = 0; |
| + state->lencode = state->distcode = state->next = state->codes; |
| + state->sane = 1; |
| + state->back = -1; |
| + Tracev((stderr, "inflate: reset\n")); |
| + return Z_OK; |
| +} |
| + |
| +int ZEXPORT inflateReset(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + state->wsize = 0; |
| + state->whave = 0; |
| + state->wnext = 0; |
| + return inflateResetKeep(strm); |
| +} |
| + |
| +int ZEXPORT inflateReset2(strm, windowBits) |
| +z_streamp strm; |
| +int windowBits; |
| +{ |
| + int wrap; |
| + struct inflate_state FAR *state; |
| + |
| + /* get the state */ |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + |
| + /* extract wrap request from windowBits parameter */ |
| + if (windowBits < 0) { |
| + wrap = 0; |
| + windowBits = -windowBits; |
| + } |
| + else { |
| + wrap = (windowBits >> 4) + 5; |
| +#ifdef GUNZIP |
| + if (windowBits < 48) |
| + windowBits &= 15; |
| +#endif |
| + } |
| + |
| + /* set number of window bits, free window if different */ |
| + if (windowBits && (windowBits < 8 || windowBits > 15)) |
| + return Z_STREAM_ERROR; |
| + if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) { |
| + ZFREE(strm, state->window); |
| + state->window = Z_NULL; |
| + } |
| + |
| + /* update state and reset the rest of it */ |
| + state->wrap = wrap; |
| + state->wbits = (unsigned)windowBits; |
| + return inflateReset(strm); |
| +} |
| + |
| +int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) |
| +z_streamp strm; |
| +int windowBits; |
| +const char *version; |
| +int stream_size; |
| +{ |
| + int ret; |
| + struct inflate_state FAR *state; |
| + |
| + if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || |
| + stream_size != (int)(sizeof(z_stream))) |
| + return Z_VERSION_ERROR; |
| + if (strm == Z_NULL) return Z_STREAM_ERROR; |
| + strm->msg = Z_NULL; /* in case we return an error */ |
| + if (strm->zalloc == (alloc_func)0) { |
| +#ifdef Z_SOLO |
| + return Z_STREAM_ERROR; |
| +#else |
| + strm->zalloc = zcalloc; |
| + strm->opaque = (voidpf)0; |
| +#endif |
| + } |
| + if (strm->zfree == (free_func)0) |
| +#ifdef Z_SOLO |
| + return Z_STREAM_ERROR; |
| +#else |
| + strm->zfree = zcfree; |
| +#endif |
| + state = (struct inflate_state FAR *) |
| + ZALLOC(strm, 1, sizeof(struct inflate_state)); |
| + if (state == Z_NULL) return Z_MEM_ERROR; |
| + Tracev((stderr, "inflate: allocated\n")); |
| + strm->state = (struct internal_state FAR *)state; |
| + state->strm = strm; |
| + state->window = Z_NULL; |
| + state->mode = HEAD; /* to pass state test in inflateReset2() */ |
| + state->check = 1L; /* 1L is the result of adler32() zero length data */ |
| + ret = inflateReset2(strm, windowBits); |
| + if (ret != Z_OK) { |
| + ZFREE(strm, state); |
| + strm->state = Z_NULL; |
| + } |
| + return ret; |
| +} |
| + |
| +int ZEXPORT inflateInit_(strm, version, stream_size) |
| +z_streamp strm; |
| +const char *version; |
| +int stream_size; |
| +{ |
| + return inflateInit2_(strm, DEF_WBITS, version, stream_size); |
| +} |
| + |
| +int ZEXPORT inflatePrime(strm, bits, value) |
| +z_streamp strm; |
| +int bits; |
| +int value; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (bits < 0) { |
| + state->hold = 0; |
| + state->bits = 0; |
| + return Z_OK; |
| + } |
| + if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR; |
| + value &= (1L << bits) - 1; |
| + state->hold += (unsigned)value << state->bits; |
| + state->bits += (uInt)bits; |
| + return Z_OK; |
| +} |
| + |
| +/* |
| + Return state with length and distance decoding tables and index sizes set to |
| + fixed code decoding. Normally this returns fixed tables from inffixed.h. |
| + If BUILDFIXED is defined, then instead this routine builds the tables the |
| + first time it's called, and returns those tables the first time and |
| + thereafter. This reduces the size of the code by about 2K bytes, in |
| + exchange for a little execution time. However, BUILDFIXED should not be |
| + used for threaded applications, since the rewriting of the tables and virgin |
| + may not be thread-safe. |
| + */ |
| +local void fixedtables(state) |
| +struct inflate_state FAR *state; |
| +{ |
| +#ifdef BUILDFIXED |
| + static int virgin = 1; |
| + static code *lenfix, *distfix; |
| + static code fixed[544]; |
| + |
| + /* build fixed huffman tables if first call (may not be thread safe) */ |
| + if (virgin) { |
| + unsigned sym, bits; |
| + static code *next; |
| + |
| + /* literal/length table */ |
| + sym = 0; |
| + while (sym < 144) state->lens[sym++] = 8; |
| + while (sym < 256) state->lens[sym++] = 9; |
| + while (sym < 280) state->lens[sym++] = 7; |
| + while (sym < 288) state->lens[sym++] = 8; |
| + next = fixed; |
| + lenfix = next; |
| + bits = 9; |
| + inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); |
| + |
| + /* distance table */ |
| + sym = 0; |
| + while (sym < 32) state->lens[sym++] = 5; |
| + distfix = next; |
| + bits = 5; |
| + inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); |
| + |
| + /* do this just once */ |
| + virgin = 0; |
| + } |
| +#else /* !BUILDFIXED */ |
| +# include "inffixed.h" |
| +#endif /* BUILDFIXED */ |
| + state->lencode = lenfix; |
| + state->lenbits = 9; |
| + state->distcode = distfix; |
| + state->distbits = 5; |
| +} |
| + |
| +#ifdef MAKEFIXED |
| +#include <stdio.h> |
| + |
| +/* |
| + Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also |
| + defines BUILDFIXED, so the tables are built on the fly. makefixed() writes |
| + those tables to stdout, which would be piped to inffixed.h. A small program |
| + can simply call makefixed to do this: |
| + |
| + void makefixed(void); |
| + |
| + int main(void) |
| + { |
| + makefixed(); |
| + return 0; |
| + } |
| + |
| + Then that can be linked with zlib built with MAKEFIXED defined and run: |
| + |
| + a.out > inffixed.h |
| + */ |
| +void makefixed() |
| +{ |
| + unsigned low, size; |
| + struct inflate_state state; |
| + |
| + fixedtables(&state); |
| + puts(" /* inffixed.h -- table for decoding fixed codes"); |
| + puts(" * Generated automatically by makefixed()."); |
| + puts(" */"); |
| + puts(""); |
| + puts(" /* WARNING: this file should *not* be used by applications."); |
| + puts(" It is part of the implementation of this library and is"); |
| + puts(" subject to change. Applications should only use zlib.h."); |
| + puts(" */"); |
| + puts(""); |
| + size = 1U << 9; |
| + printf(" static const code lenfix[%u] = {", size); |
| + low = 0; |
| + for (;;) { |
| + if ((low % 7) == 0) printf("\n "); |
| + printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op, |
| + state.lencode[low].bits, state.lencode[low].val); |
| + if (++low == size) break; |
| + putchar(','); |
| + } |
| + puts("\n };"); |
| + size = 1U << 5; |
| + printf("\n static const code distfix[%u] = {", size); |
| + low = 0; |
| + for (;;) { |
| + if ((low % 6) == 0) printf("\n "); |
| + printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits, |
| + state.distcode[low].val); |
| + if (++low == size) break; |
| + putchar(','); |
| + } |
| + puts("\n };"); |
| +} |
| +#endif /* MAKEFIXED */ |
| + |
| +/* |
| + Update the window with the last wsize (normally 32K) bytes written before |
| + returning. If window does not exist yet, create it. This is only called |
| + when a window is already in use, or when output has been written during this |
| + inflate call, but the end of the deflate stream has not been reached yet. |
| + It is also called to create a window for dictionary data when a dictionary |
| + is loaded. |
| + |
| + Providing output buffers larger than 32K to inflate() should provide a speed |
| + advantage, since only the last 32K of output is copied to the sliding window |
| + upon return from inflate(), and since all distances after the first 32K of |
| + output will fall in the output data, making match copies simpler and faster. |
| + The advantage may be dependent on the size of the processor's data caches. |
| + */ |
| +local int updatewindow(strm, end, copy) |
| +z_streamp strm; |
| +const Bytef *end; |
| +unsigned copy; |
| +{ |
| + struct inflate_state FAR *state; |
| + unsigned dist; |
| + |
| + state = (struct inflate_state FAR *)strm->state; |
| + |
| + /* if it hasn't been done already, allocate space for the window */ |
| + if (state->window == Z_NULL) { |
| + unsigned wsize = 1U << state->wbits; |
| + state->window = (unsigned char FAR *) |
| + ZALLOC(strm, wsize + CHUNKCOPY_CHUNK_SIZE, |
| + sizeof(unsigned char)); |
| + if (state->window == Z_NULL) return 1; |
| +#ifdef INFLATE_CLEAR_UNUSED_UNDEFINED |
| + /* Copies from the overflow portion of this buffer are undefined and |
| + may cause analysis tools to raise a warning if we don't initialize |
| + it. However, this undefined data overwrites other undefined data |
| + and is subsequently either overwritten or left deliberately |
| + undefined at the end of decode; so there's really no point. |
| + */ |
| + memset(state->window + wsize, 0, CHUNKCOPY_CHUNK_SIZE); |
| +#endif |
| + } |
| + |
| + /* if window not in use yet, initialize */ |
| + if (state->wsize == 0) { |
| + state->wsize = 1U << state->wbits; |
| + state->wnext = 0; |
| + state->whave = 0; |
| + } |
| + |
| + /* copy state->wsize or less output bytes into the circular window */ |
| + if (copy >= state->wsize) { |
| + zmemcpy(state->window, end - state->wsize, state->wsize); |
| + state->wnext = 0; |
| + state->whave = state->wsize; |
| + } |
| + else { |
| + dist = state->wsize - state->wnext; |
| + if (dist > copy) dist = copy; |
| + zmemcpy(state->window + state->wnext, end - copy, dist); |
| + copy -= dist; |
| + if (copy) { |
| + zmemcpy(state->window, end - copy, copy); |
| + state->wnext = copy; |
| + state->whave = state->wsize; |
| + } |
| + else { |
| + state->wnext += dist; |
| + if (state->wnext == state->wsize) state->wnext = 0; |
| + if (state->whave < state->wsize) state->whave += dist; |
| + } |
| + } |
| + return 0; |
| +} |
| + |
| +/* Macros for inflate(): */ |
| + |
| +/* check function to use adler32() for zlib or crc32() for gzip */ |
| +#ifdef GUNZIP |
| +# define UPDATE(check, buf, len) \ |
| + (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) |
| +#else |
| +# define UPDATE(check, buf, len) adler32(check, buf, len) |
| +#endif |
| + |
| +/* check macros for header crc */ |
| +#ifdef GUNZIP |
| +# define CRC2(check, word) \ |
| + do { \ |
| + hbuf[0] = (unsigned char)(word); \ |
| + hbuf[1] = (unsigned char)((word) >> 8); \ |
| + check = crc32(check, hbuf, 2); \ |
| + } while (0) |
| + |
| +# define CRC4(check, word) \ |
| + do { \ |
| + hbuf[0] = (unsigned char)(word); \ |
| + hbuf[1] = (unsigned char)((word) >> 8); \ |
| + hbuf[2] = (unsigned char)((word) >> 16); \ |
| + hbuf[3] = (unsigned char)((word) >> 24); \ |
| + check = crc32(check, hbuf, 4); \ |
| + } while (0) |
| +#endif |
| + |
| +/* Load registers with state in inflate() for speed */ |
| +#define LOAD() \ |
| + do { \ |
| + put = strm->next_out; \ |
| + left = strm->avail_out; \ |
| + next = strm->next_in; \ |
| + have = strm->avail_in; \ |
| + hold = state->hold; \ |
| + bits = state->bits; \ |
| + } while (0) |
| + |
| +/* Restore state from registers in inflate() */ |
| +#define RESTORE() \ |
| + do { \ |
| + strm->next_out = put; \ |
| + strm->avail_out = left; \ |
| + strm->next_in = next; \ |
| + strm->avail_in = have; \ |
| + state->hold = hold; \ |
| + state->bits = bits; \ |
| + } while (0) |
| + |
| +/* Clear the input bit accumulator */ |
| +#define INITBITS() \ |
| + do { \ |
| + hold = 0; \ |
| + bits = 0; \ |
| + } while (0) |
| + |
| +/* Get a byte of input into the bit accumulator, or return from inflate() |
| + if there is no input available. */ |
| +#define PULLBYTE() \ |
| + do { \ |
| + if (have == 0) goto inf_leave; \ |
| + have--; \ |
| + hold += (unsigned long)(*next++) << bits; \ |
| + bits += 8; \ |
| + } while (0) |
| + |
| +/* Assure that there are at least n bits in the bit accumulator. If there is |
| + not enough available input to do that, then return from inflate(). */ |
| +#define NEEDBITS(n) \ |
| + do { \ |
| + while (bits < (unsigned)(n)) \ |
| + PULLBYTE(); \ |
| + } while (0) |
| + |
| +/* Return the low n bits of the bit accumulator (n < 16) */ |
| +#define BITS(n) \ |
| + ((unsigned)hold & ((1U << (n)) - 1)) |
| + |
| +/* Remove n bits from the bit accumulator */ |
| +#define DROPBITS(n) \ |
| + do { \ |
| + hold >>= (n); \ |
| + bits -= (unsigned)(n); \ |
| + } while (0) |
| + |
| +/* Remove zero to seven bits as needed to go to a byte boundary */ |
| +#define BYTEBITS() \ |
| + do { \ |
| + hold >>= bits & 7; \ |
| + bits -= bits & 7; \ |
| + } while (0) |
| + |
| +/* |
| + inflate() uses a state machine to process as much input data and generate as |
| + much output data as possible before returning. The state machine is |
| + structured roughly as follows: |
| + |
| + for (;;) switch (state) { |
| + ... |
| + case STATEn: |
| + if (not enough input data or output space to make progress) |
| + return; |
| + ... make progress ... |
| + state = STATEm; |
| + break; |
| + ... |
| + } |
| + |
| + so when inflate() is called again, the same case is attempted again, and |
| + if the appropriate resources are provided, the machine proceeds to the |
| + next state. The NEEDBITS() macro is usually the way the state evaluates |
| + whether it can proceed or should return. NEEDBITS() does the return if |
| + the requested bits are not available. The typical use of the BITS macros |
| + is: |
| + |
| + NEEDBITS(n); |
| + ... do something with BITS(n) ... |
| + DROPBITS(n); |
| + |
| + where NEEDBITS(n) either returns from inflate() if there isn't enough |
| + input left to load n bits into the accumulator, or it continues. BITS(n) |
| + gives the low n bits in the accumulator. When done, DROPBITS(n) drops |
| + the low n bits off the accumulator. INITBITS() clears the accumulator |
| + and sets the number of available bits to zero. BYTEBITS() discards just |
| + enough bits to put the accumulator on a byte boundary. After BYTEBITS() |
| + and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. |
| + |
| + NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return |
| + if there is no input available. The decoding of variable length codes uses |
| + PULLBYTE() directly in order to pull just enough bytes to decode the next |
| + code, and no more. |
| + |
| + Some states loop until they get enough input, making sure that enough |
| + state information is maintained to continue the loop where it left off |
| + if NEEDBITS() returns in the loop. For example, want, need, and keep |
| + would all have to actually be part of the saved state in case NEEDBITS() |
| + returns: |
| + |
| + case STATEw: |
| + while (want < need) { |
| + NEEDBITS(n); |
| + keep[want++] = BITS(n); |
| + DROPBITS(n); |
| + } |
| + state = STATEx; |
| + case STATEx: |
| + |
| + As shown above, if the next state is also the next case, then the break |
| + is omitted. |
| + |
| + A state may also return if there is not enough output space available to |
| + complete that state. Those states are copying stored data, writing a |
| + literal byte, and copying a matching string. |
| + |
| + When returning, a "goto inf_leave" is used to update the total counters, |
| + update the check value, and determine whether any progress has been made |
| + during that inflate() call in order to return the proper return code. |
| + Progress is defined as a change in either strm->avail_in or strm->avail_out. |
| + When there is a window, goto inf_leave will update the window with the last |
| + output written. If a goto inf_leave occurs in the middle of decompression |
| + and there is no window currently, goto inf_leave will create one and copy |
| + output to the window for the next call of inflate(). |
| + |
| + In this implementation, the flush parameter of inflate() only affects the |
| + return code (per zlib.h). inflate() always writes as much as possible to |
| + strm->next_out, given the space available and the provided input--the effect |
| + documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers |
| + the allocation of and copying into a sliding window until necessary, which |
| + provides the effect documented in zlib.h for Z_FINISH when the entire input |
| + stream available. So the only thing the flush parameter actually does is: |
| + when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it |
| + will return Z_BUF_ERROR if it has not reached the end of the stream. |
| + */ |
| + |
| +int ZEXPORT inflate(strm, flush) |
| +z_streamp strm; |
| +int flush; |
| +{ |
| + struct inflate_state FAR *state; |
| + z_const unsigned char FAR *next; /* next input */ |
| + unsigned char FAR *put; /* next output */ |
| + unsigned have, left; /* available input and output */ |
| + unsigned long hold; /* bit buffer */ |
| + unsigned bits; /* bits in bit buffer */ |
| + unsigned in, out; /* save starting available input and output */ |
| + unsigned copy; /* number of stored or match bytes to copy */ |
| + unsigned char FAR *from; /* where to copy match bytes from */ |
| + 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 */ |
| +#ifdef GUNZIP |
| + unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ |
| +#endif |
| + static const unsigned short order[19] = /* permutation of code lengths */ |
| + {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
| + |
| + if (inflateStateCheck(strm) || strm->next_out == Z_NULL || |
| + (strm->next_in == Z_NULL && strm->avail_in != 0)) |
| + return Z_STREAM_ERROR; |
| + |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ |
| + LOAD(); |
| + in = have; |
| + out = left; |
| + ret = Z_OK; |
| + for (;;) |
| + switch (state->mode) { |
| + case HEAD: |
| + if (state->wrap == 0) { |
| + state->mode = TYPEDO; |
| + break; |
| + } |
| + NEEDBITS(16); |
| +#ifdef GUNZIP |
| + if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ |
| + if (state->wbits == 0) |
| + state->wbits = 15; |
| + state->check = crc32(0L, Z_NULL, 0); |
| + CRC2(state->check, hold); |
| + INITBITS(); |
| + state->mode = FLAGS; |
| + break; |
| + } |
| + state->flags = 0; /* expect zlib header */ |
| + if (state->head != Z_NULL) |
| + state->head->done = -1; |
| + if (!(state->wrap & 1) || /* check if zlib header allowed */ |
| +#else |
| + if ( |
| +#endif |
| + ((BITS(8) << 8) + (hold >> 8)) % 31) { |
| + strm->msg = (char *)"incorrect header check"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + if (BITS(4) != Z_DEFLATED) { |
| + strm->msg = (char *)"unknown compression method"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + DROPBITS(4); |
| + len = BITS(4) + 8; |
| + if (state->wbits == 0) |
| + state->wbits = len; |
| + if (len > 15 || len > state->wbits) { |
| + strm->msg = (char *)"invalid window size"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + state->dmax = 1U << len; |
| + Tracev((stderr, "inflate: zlib header ok\n")); |
| + strm->adler = state->check = adler32(0L, Z_NULL, 0); |
| + state->mode = hold & 0x200 ? DICTID : TYPE; |
| + INITBITS(); |
| + break; |
| +#ifdef GUNZIP |
| + case FLAGS: |
| + NEEDBITS(16); |
| + state->flags = (int)(hold); |
| + if ((state->flags & 0xff) != Z_DEFLATED) { |
| + strm->msg = (char *)"unknown compression method"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + if (state->flags & 0xe000) { |
| + strm->msg = (char *)"unknown header flags set"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + if (state->head != Z_NULL) |
| + state->head->text = (int)((hold >> 8) & 1); |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + CRC2(state->check, hold); |
| + INITBITS(); |
| + state->mode = TIME; |
| + case TIME: |
| + NEEDBITS(32); |
| + if (state->head != Z_NULL) |
| + state->head->time = hold; |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + CRC4(state->check, hold); |
| + INITBITS(); |
| + state->mode = OS; |
| + case OS: |
| + NEEDBITS(16); |
| + if (state->head != Z_NULL) { |
| + state->head->xflags = (int)(hold & 0xff); |
| + state->head->os = (int)(hold >> 8); |
| + } |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + CRC2(state->check, hold); |
| + INITBITS(); |
| + state->mode = EXLEN; |
| + case EXLEN: |
| + if (state->flags & 0x0400) { |
| + NEEDBITS(16); |
| + state->length = (unsigned)(hold); |
| + if (state->head != Z_NULL) |
| + state->head->extra_len = (unsigned)hold; |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + CRC2(state->check, hold); |
| + INITBITS(); |
| + } |
| + else if (state->head != Z_NULL) |
| + state->head->extra = Z_NULL; |
| + state->mode = EXTRA; |
| + case EXTRA: |
| + if (state->flags & 0x0400) { |
| + copy = state->length; |
| + if (copy > have) copy = have; |
| + if (copy) { |
| + if (state->head != Z_NULL && |
| + state->head->extra != Z_NULL) { |
| + len = state->head->extra_len - state->length; |
| + zmemcpy(state->head->extra + len, next, |
| + len + copy > state->head->extra_max ? |
| + state->head->extra_max - len : copy); |
| + } |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + state->check = crc32(state->check, next, copy); |
| + have -= copy; |
| + next += copy; |
| + state->length -= copy; |
| + } |
| + if (state->length) goto inf_leave; |
| + } |
| + state->length = 0; |
| + state->mode = NAME; |
| + case NAME: |
| + if (state->flags & 0x0800) { |
| + if (have == 0) goto inf_leave; |
| + copy = 0; |
| + do { |
| + len = (unsigned)(next[copy++]); |
| + if (state->head != Z_NULL && |
| + state->head->name != Z_NULL && |
| + state->length < state->head->name_max) |
| + state->head->name[state->length++] = (Bytef)len; |
| + } while (len && copy < have); |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + state->check = crc32(state->check, next, copy); |
| + have -= copy; |
| + next += copy; |
| + if (len) goto inf_leave; |
| + } |
| + else if (state->head != Z_NULL) |
| + state->head->name = Z_NULL; |
| + state->length = 0; |
| + state->mode = COMMENT; |
| + case COMMENT: |
| + if (state->flags & 0x1000) { |
| + if (have == 0) goto inf_leave; |
| + copy = 0; |
| + do { |
| + len = (unsigned)(next[copy++]); |
| + if (state->head != Z_NULL && |
| + state->head->comment != Z_NULL && |
| + state->length < state->head->comm_max) |
| + state->head->comment[state->length++] = (Bytef)len; |
| + } while (len && copy < have); |
| + if ((state->flags & 0x0200) && (state->wrap & 4)) |
| + state->check = crc32(state->check, next, copy); |
| + have -= copy; |
| + next += copy; |
| + if (len) goto inf_leave; |
| + } |
| + else if (state->head != Z_NULL) |
| + state->head->comment = Z_NULL; |
| + state->mode = HCRC; |
| + case HCRC: |
| + if (state->flags & 0x0200) { |
| + NEEDBITS(16); |
| + if ((state->wrap & 4) && hold != (state->check & 0xffff)) { |
| + strm->msg = (char *)"header crc mismatch"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + INITBITS(); |
| + } |
| + if (state->head != Z_NULL) { |
| + state->head->hcrc = (int)((state->flags >> 9) & 1); |
| + state->head->done = 1; |
| + } |
| + strm->adler = state->check = crc32(0L, Z_NULL, 0); |
| + state->mode = TYPE; |
| + break; |
| +#endif |
| + case DICTID: |
| + NEEDBITS(32); |
| + strm->adler = state->check = ZSWAP32(hold); |
| + INITBITS(); |
| + state->mode = DICT; |
| + case DICT: |
| + if (state->havedict == 0) { |
| + RESTORE(); |
| + return Z_NEED_DICT; |
| + } |
| + strm->adler = state->check = adler32(0L, Z_NULL, 0); |
| + state->mode = TYPE; |
| + case TYPE: |
| + if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave; |
| + case TYPEDO: |
| + if (state->last) { |
| + BYTEBITS(); |
| + state->mode = CHECK; |
| + break; |
| + } |
| + NEEDBITS(3); |
| + state->last = BITS(1); |
| + DROPBITS(1); |
| + switch (BITS(2)) { |
| + case 0: /* stored block */ |
| + Tracev((stderr, "inflate: stored block%s\n", |
| + state->last ? " (last)" : "")); |
| + state->mode = STORED; |
| + break; |
| + case 1: /* fixed block */ |
| + fixedtables(state); |
| + Tracev((stderr, "inflate: fixed codes block%s\n", |
| + state->last ? " (last)" : "")); |
| + state->mode = LEN_; /* decode codes */ |
| + if (flush == Z_TREES) { |
| + DROPBITS(2); |
| + goto inf_leave; |
| + } |
| + break; |
| + case 2: /* dynamic block */ |
| + Tracev((stderr, "inflate: dynamic codes block%s\n", |
| + state->last ? " (last)" : "")); |
| + state->mode = TABLE; |
| + break; |
| + case 3: |
| + strm->msg = (char *)"invalid block type"; |
| + state->mode = BAD; |
| + } |
| + DROPBITS(2); |
| + break; |
| + case STORED: |
| + BYTEBITS(); /* go to byte boundary */ |
| + NEEDBITS(32); |
| + if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { |
| + strm->msg = (char *)"invalid stored block lengths"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + state->length = (unsigned)hold & 0xffff; |
| + Tracev((stderr, "inflate: stored length %u\n", |
| + state->length)); |
| + INITBITS(); |
| + state->mode = COPY_; |
| + if (flush == Z_TREES) goto inf_leave; |
| + case COPY_: |
| + state->mode = COPY; |
| + case COPY: |
| + copy = state->length; |
| + if (copy) { |
| + if (copy > have) copy = have; |
| + if (copy > left) copy = left; |
| + if (copy == 0) goto inf_leave; |
| + zmemcpy(put, next, copy); |
| + have -= copy; |
| + next += copy; |
| + left -= copy; |
| + put += copy; |
| + state->length -= copy; |
| + break; |
| + } |
| + Tracev((stderr, "inflate: stored end\n")); |
| + state->mode = TYPE; |
| + break; |
| + case TABLE: |
| + NEEDBITS(14); |
| + state->nlen = BITS(5) + 257; |
| + DROPBITS(5); |
| + state->ndist = BITS(5) + 1; |
| + DROPBITS(5); |
| + state->ncode = BITS(4) + 4; |
| + DROPBITS(4); |
| +#ifndef PKZIP_BUG_WORKAROUND |
| + if (state->nlen > 286 || state->ndist > 30) { |
| + strm->msg = (char *)"too many length or distance symbols"; |
| + state->mode = BAD; |
| + break; |
| + } |
| +#endif |
| + Tracev((stderr, "inflate: table sizes ok\n")); |
| + state->have = 0; |
| + state->mode = LENLENS; |
| + case LENLENS: |
| + while (state->have < state->ncode) { |
| + NEEDBITS(3); |
| + state->lens[order[state->have++]] = (unsigned short)BITS(3); |
| + DROPBITS(3); |
| + } |
| + while (state->have < 19) |
| + state->lens[order[state->have++]] = 0; |
| + state->next = state->codes; |
| + state->lencode = (const code FAR *)(state->next); |
| + state->lenbits = 7; |
| + ret = inflate_table(CODES, state->lens, 19, &(state->next), |
| + &(state->lenbits), state->work); |
| + if (ret) { |
| + strm->msg = (char *)"invalid code lengths set"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + Tracev((stderr, "inflate: code lengths ok\n")); |
| + state->have = 0; |
| + state->mode = CODELENS; |
| + case CODELENS: |
| + while (state->have < state->nlen + state->ndist) { |
| + for (;;) { |
| + here = state->lencode[BITS(state->lenbits)]; |
| + if ((unsigned)(here.bits) <= bits) break; |
| + PULLBYTE(); |
| + } |
| + if (here.val < 16) { |
| + DROPBITS(here.bits); |
| + state->lens[state->have++] = here.val; |
| + } |
| + else { |
| + if (here.val == 16) { |
| + NEEDBITS(here.bits + 2); |
| + DROPBITS(here.bits); |
| + if (state->have == 0) { |
| + strm->msg = (char *)"invalid bit length repeat"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + len = state->lens[state->have - 1]; |
| + copy = 3 + BITS(2); |
| + DROPBITS(2); |
| + } |
| + else if (here.val == 17) { |
| + NEEDBITS(here.bits + 3); |
| + DROPBITS(here.bits); |
| + len = 0; |
| + copy = 3 + BITS(3); |
| + DROPBITS(3); |
| + } |
| + else { |
| + NEEDBITS(here.bits + 7); |
| + DROPBITS(here.bits); |
| + len = 0; |
| + copy = 11 + BITS(7); |
| + DROPBITS(7); |
| + } |
| + if (state->have + copy > state->nlen + state->ndist) { |
| + strm->msg = (char *)"invalid bit length repeat"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + while (copy--) |
| + state->lens[state->have++] = (unsigned short)len; |
| + } |
| + } |
| + |
| + /* handle error breaks in while */ |
| + if (state->mode == BAD) break; |
| + |
| + /* check for end-of-block code (better have one) */ |
| + if (state->lens[256] == 0) { |
| + strm->msg = (char *)"invalid code -- missing end-of-block"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + |
| + /* build code tables -- note: do not change the lenbits or distbits |
| + values here (9 and 6) without reading the comments in inftrees.h |
| + concerning the ENOUGH constants, which depend on those values */ |
| + state->next = state->codes; |
| + state->lencode = (const code FAR *)(state->next); |
| + state->lenbits = 9; |
| + ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), |
| + &(state->lenbits), state->work); |
| + if (ret) { |
| + strm->msg = (char *)"invalid literal/lengths set"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + state->distcode = (const code FAR *)(state->next); |
| + state->distbits = 6; |
| + ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, |
| + &(state->next), &(state->distbits), state->work); |
| + if (ret) { |
| + strm->msg = (char *)"invalid distances set"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + Tracev((stderr, "inflate: codes ok\n")); |
| + state->mode = LEN_; |
| + if (flush == Z_TREES) goto inf_leave; |
| + case LEN_: |
| + state->mode = LEN; |
| + case LEN: |
| + if (have >= 6 && left >= 258) { |
| + RESTORE(); |
| + inflate_fast(strm, out); |
| + LOAD(); |
| + if (state->mode == TYPE) |
| + state->back = -1; |
| + break; |
| + } |
| + state->back = 0; |
| + for (;;) { |
| + here = state->lencode[BITS(state->lenbits)]; |
| + if ((unsigned)(here.bits) <= bits) break; |
| + PULLBYTE(); |
| + } |
| + if (here.op && (here.op & 0xf0) == 0) { |
| + last = here; |
| + for (;;) { |
| + here = state->lencode[last.val + |
| + (BITS(last.bits + last.op) >> last.bits)]; |
| + if ((unsigned)(last.bits + here.bits) <= bits) break; |
| + PULLBYTE(); |
| + } |
| + DROPBITS(last.bits); |
| + state->back += last.bits; |
| + } |
| + DROPBITS(here.bits); |
| + state->back += here.bits; |
| + state->length = (unsigned)here.val; |
| + if ((int)(here.op) == 0) { |
| + Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? |
| + "inflate: literal '%c'\n" : |
| + "inflate: literal 0x%02x\n", here.val)); |
| + state->mode = LIT; |
| + break; |
| + } |
| + if (here.op & 32) { |
| + Tracevv((stderr, "inflate: end of block\n")); |
| + state->back = -1; |
| + state->mode = TYPE; |
| + break; |
| + } |
| + if (here.op & 64) { |
| + strm->msg = (char *)"invalid literal/length code"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + state->extra = (unsigned)(here.op) & 15; |
| + state->mode = LENEXT; |
| + case LENEXT: |
| + if (state->extra) { |
| + NEEDBITS(state->extra); |
| + state->length += BITS(state->extra); |
| + DROPBITS(state->extra); |
| + state->back += state->extra; |
| + } |
| + Tracevv((stderr, "inflate: length %u\n", state->length)); |
| + state->was = state->length; |
| + state->mode = DIST; |
| + case DIST: |
| + for (;;) { |
| + here = state->distcode[BITS(state->distbits)]; |
| + if ((unsigned)(here.bits) <= bits) break; |
| + PULLBYTE(); |
| + } |
| + if ((here.op & 0xf0) == 0) { |
| + last = here; |
| + for (;;) { |
| + here = state->distcode[last.val + |
| + (BITS(last.bits + last.op) >> last.bits)]; |
| + if ((unsigned)(last.bits + here.bits) <= bits) break; |
| + PULLBYTE(); |
| + } |
| + DROPBITS(last.bits); |
| + state->back += last.bits; |
| + } |
| + DROPBITS(here.bits); |
| + state->back += here.bits; |
| + if (here.op & 64) { |
| + strm->msg = (char *)"invalid distance code"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + state->offset = (unsigned)here.val; |
| + state->extra = (unsigned)(here.op) & 15; |
| + state->mode = DISTEXT; |
| + case DISTEXT: |
| + if (state->extra) { |
| + NEEDBITS(state->extra); |
| + state->offset += BITS(state->extra); |
| + DROPBITS(state->extra); |
| + state->back += state->extra; |
| + } |
| +#ifdef INFLATE_STRICT |
| + if (state->offset > state->dmax) { |
| + strm->msg = (char *)"invalid distance too far back"; |
| + state->mode = BAD; |
| + break; |
| + } |
| +#endif |
| + Tracevv((stderr, "inflate: distance %u\n", state->offset)); |
| + state->mode = MATCH; |
| + case MATCH: |
| + if (left == 0) goto inf_leave; |
| + copy = out - left; |
| + if (state->offset > copy) { /* copy from window */ |
| + copy = state->offset - copy; |
| + if (copy > state->whave) { |
| + if (state->sane) { |
| + strm->msg = (char *)"invalid distance too far back"; |
| + state->mode = BAD; |
| + break; |
| + } |
| +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR |
| + Trace((stderr, "inflate.c too far\n")); |
| + copy -= state->whave; |
| + if (copy > state->length) copy = state->length; |
| + if (copy > left) copy = left; |
| + left -= copy; |
| + state->length -= copy; |
| + do { |
| + *put++ = 0; |
| + } while (--copy); |
| + if (state->length == 0) state->mode = LEN; |
| + break; |
| +#endif |
| + } |
| + if (copy > state->wnext) { |
| + copy -= state->wnext; |
| + from = state->window + (state->wsize - copy); |
| + } |
| + else |
| + from = state->window + (state->wnext - copy); |
| + if (copy > state->length) copy = state->length; |
| + if (copy > left) copy = left; |
| + put = chunkcopy_safe(put, from, copy, put + left); |
| + } |
| + else { /* copy from output */ |
| + copy = state->length; |
| + if (copy > left) copy = left; |
| + put = chunkcopy_lapped_safe(put, state->offset, copy, put + left); |
| + } |
| + left -= copy; |
| + state->length -= copy; |
| + if (state->length == 0) state->mode = LEN; |
| + break; |
| + case LIT: |
| + if (left == 0) goto inf_leave; |
| + *put++ = (unsigned char)(state->length); |
| + left--; |
| + state->mode = LEN; |
| + break; |
| + case CHECK: |
| + if (state->wrap) { |
| + NEEDBITS(32); |
| + out -= left; |
| + strm->total_out += out; |
| + state->total += out; |
| + if ((state->wrap & 4) && out) |
| + strm->adler = state->check = |
| + UPDATE(state->check, put - out, out); |
| + out = left; |
| + if ((state->wrap & 4) && ( |
| +#ifdef GUNZIP |
| + state->flags ? hold : |
| +#endif |
| + ZSWAP32(hold)) != state->check) { |
| + strm->msg = (char *)"incorrect data check"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + INITBITS(); |
| + Tracev((stderr, "inflate: check matches trailer\n")); |
| + } |
| +#ifdef GUNZIP |
| + state->mode = LENGTH; |
| + case LENGTH: |
| + if (state->wrap && state->flags) { |
| + NEEDBITS(32); |
| + if (hold != (state->total & 0xffffffffUL)) { |
| + strm->msg = (char *)"incorrect length check"; |
| + state->mode = BAD; |
| + break; |
| + } |
| + INITBITS(); |
| + Tracev((stderr, "inflate: length matches trailer\n")); |
| + } |
| +#endif |
| + state->mode = DONE; |
| + case DONE: |
| + ret = Z_STREAM_END; |
| + goto inf_leave; |
| + case BAD: |
| + ret = Z_DATA_ERROR; |
| + goto inf_leave; |
| + case MEM: |
| + return Z_MEM_ERROR; |
| + case SYNC: |
| + default: |
| + return Z_STREAM_ERROR; |
| + } |
| + |
| + /* |
| + Return from inflate(), updating the total counts and the check value. |
| + If there was no progress during the inflate() call, return a buffer |
| + error. Call updatewindow() to create and/or update the window state. |
| + Note: a memory error from inflate() is non-recoverable. |
| + */ |
| + inf_leave: |
| + RESTORE(); |
| + if (state->wsize || (out != strm->avail_out && state->mode < BAD && |
| + (state->mode < CHECK || flush != Z_FINISH))) |
| + if (updatewindow(strm, strm->next_out, out - strm->avail_out)) { |
| + state->mode = MEM; |
| + return Z_MEM_ERROR; |
| + } |
| + in -= strm->avail_in; |
| + out -= strm->avail_out; |
| + strm->total_in += in; |
| + strm->total_out += out; |
| + state->total += out; |
| + if ((state->wrap & 4) && out) |
| + strm->adler = state->check = |
| + UPDATE(state->check, strm->next_out - out, out); |
| + strm->data_type = (int)state->bits + (state->last ? 64 : 0) + |
| + (state->mode == TYPE ? 128 : 0) + |
| + (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0); |
| + if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) |
| + ret = Z_BUF_ERROR; |
| + return ret; |
| +} |
| + |
| +int ZEXPORT inflateEnd(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + if (inflateStateCheck(strm)) |
| + return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (state->window != Z_NULL) ZFREE(strm, state->window); |
| + ZFREE(strm, strm->state); |
| + strm->state = Z_NULL; |
| + Tracev((stderr, "inflate: end\n")); |
| + return Z_OK; |
| +} |
| + |
| +int ZEXPORT inflateGetDictionary(strm, dictionary, dictLength) |
| +z_streamp strm; |
| +Bytef *dictionary; |
| +uInt *dictLength; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + /* check state */ |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + |
| + /* copy dictionary */ |
| + if (state->whave && dictionary != Z_NULL) { |
| + zmemcpy(dictionary, state->window + state->wnext, |
| + state->whave - state->wnext); |
| + zmemcpy(dictionary + state->whave - state->wnext, |
| + state->window, state->wnext); |
| + } |
| + if (dictLength != Z_NULL) |
| + *dictLength = state->whave; |
| + return Z_OK; |
| +} |
| + |
| +int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength) |
| +z_streamp strm; |
| +const Bytef *dictionary; |
| +uInt dictLength; |
| +{ |
| + struct inflate_state FAR *state; |
| + unsigned long dictid; |
| + int ret; |
| + |
| + /* check state */ |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (state->wrap != 0 && state->mode != DICT) |
| + return Z_STREAM_ERROR; |
| + |
| + /* check for correct dictionary identifier */ |
| + if (state->mode == DICT) { |
| + dictid = adler32(0L, Z_NULL, 0); |
| + dictid = adler32(dictid, dictionary, dictLength); |
| + if (dictid != state->check) |
| + return Z_DATA_ERROR; |
| + } |
| + |
| + /* copy dictionary to window using updatewindow(), which will amend the |
| + existing dictionary if appropriate */ |
| + ret = updatewindow(strm, dictionary + dictLength, dictLength); |
| + if (ret) { |
| + state->mode = MEM; |
| + return Z_MEM_ERROR; |
| + } |
| + state->havedict = 1; |
| + Tracev((stderr, "inflate: dictionary set\n")); |
| + return Z_OK; |
| +} |
| + |
| +int ZEXPORT inflateGetHeader(strm, head) |
| +z_streamp strm; |
| +gz_headerp head; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + /* check state */ |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if ((state->wrap & 2) == 0) return Z_STREAM_ERROR; |
| + |
| + /* save header structure */ |
| + state->head = head; |
| + head->done = 0; |
| + return Z_OK; |
| +} |
| + |
| +/* |
| + Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found |
| + or when out of input. When called, *have is the number of pattern bytes |
| + found in order so far, in 0..3. On return *have is updated to the new |
| + state. If on return *have equals four, then the pattern was found and the |
| + return value is how many bytes were read including the last byte of the |
| + pattern. If *have is less than four, then the pattern has not been found |
| + yet and the return value is len. In the latter case, syncsearch() can be |
| + called again with more data and the *have state. *have is initialized to |
| + zero for the first call. |
| + */ |
| +local unsigned syncsearch(have, buf, len) |
| +unsigned FAR *have; |
| +const unsigned char FAR *buf; |
| +unsigned len; |
| +{ |
| + unsigned got; |
| + unsigned next; |
| + |
| + got = *have; |
| + next = 0; |
| + while (next < len && got < 4) { |
| + if ((int)(buf[next]) == (got < 2 ? 0 : 0xff)) |
| + got++; |
| + else if (buf[next]) |
| + got = 0; |
| + else |
| + got = 4 - got; |
| + next++; |
| + } |
| + *have = got; |
| + return next; |
| +} |
| + |
| +int ZEXPORT inflateSync(strm) |
| +z_streamp strm; |
| +{ |
| + unsigned len; /* number of bytes to look at or looked at */ |
| + unsigned long in, out; /* temporary to save total_in and total_out */ |
| + unsigned char buf[4]; /* to restore bit buffer to byte string */ |
| + struct inflate_state FAR *state; |
| + |
| + /* check parameters */ |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR; |
| + |
| + /* if first time, start search in bit buffer */ |
| + if (state->mode != SYNC) { |
| + state->mode = SYNC; |
| + state->hold <<= state->bits & 7; |
| + state->bits -= state->bits & 7; |
| + len = 0; |
| + while (state->bits >= 8) { |
| + buf[len++] = (unsigned char)(state->hold); |
| + state->hold >>= 8; |
| + state->bits -= 8; |
| + } |
| + state->have = 0; |
| + syncsearch(&(state->have), buf, len); |
| + } |
| + |
| + /* search available input */ |
| + len = syncsearch(&(state->have), strm->next_in, strm->avail_in); |
| + strm->avail_in -= len; |
| + strm->next_in += len; |
| + strm->total_in += len; |
| + |
| + /* return no joy or set up to restart inflate() on a new block */ |
| + if (state->have != 4) return Z_DATA_ERROR; |
| + in = strm->total_in; out = strm->total_out; |
| + inflateReset(strm); |
| + strm->total_in = in; strm->total_out = out; |
| + state->mode = TYPE; |
| + return Z_OK; |
| +} |
| + |
| +/* |
| + Returns true if inflate is currently at the end of a block generated by |
| + Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP |
| + implementation to provide an additional safety check. PPP uses |
| + Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored |
| + block. When decompressing, PPP checks that at the end of input packet, |
| + inflate is waiting for these length bytes. |
| + */ |
| +int ZEXPORT inflateSyncPoint(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + return state->mode == STORED && state->bits == 0; |
| +} |
| + |
| +int ZEXPORT inflateCopy(dest, source) |
| +z_streamp dest; |
| +z_streamp source; |
| +{ |
| + struct inflate_state FAR *state; |
| + struct inflate_state FAR *copy; |
| + unsigned char FAR *window; |
| + unsigned wsize; |
| + |
| + /* check input */ |
| + if (inflateStateCheck(source) || dest == Z_NULL) |
| + return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)source->state; |
| + |
| + /* allocate space */ |
| + copy = (struct inflate_state FAR *) |
| + ZALLOC(source, 1, sizeof(struct inflate_state)); |
| + if (copy == Z_NULL) return Z_MEM_ERROR; |
| + window = Z_NULL; |
| + if (state->window != Z_NULL) { |
| + window = (unsigned char FAR *) |
| + ZALLOC(source, 1U << state->wbits, sizeof(unsigned char)); |
| + if (window == Z_NULL) { |
| + ZFREE(source, copy); |
| + return Z_MEM_ERROR; |
| + } |
| + } |
| + |
| + /* copy state */ |
| + zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream)); |
| + zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state)); |
| + copy->strm = dest; |
| + if (state->lencode >= state->codes && |
| + state->lencode <= state->codes + ENOUGH - 1) { |
| + copy->lencode = copy->codes + (state->lencode - state->codes); |
| + copy->distcode = copy->codes + (state->distcode - state->codes); |
| + } |
| + copy->next = copy->codes + (state->next - state->codes); |
| + if (window != Z_NULL) { |
| + wsize = 1U << state->wbits; |
| + zmemcpy(window, state->window, wsize); |
| + } |
| + copy->window = window; |
| + dest->state = (struct internal_state FAR *)copy; |
| + return Z_OK; |
| +} |
| + |
| +int ZEXPORT inflateUndermine(strm, subvert) |
| +z_streamp strm; |
| +int subvert; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR |
| + state->sane = !subvert; |
| + return Z_OK; |
| +#else |
| + (void)subvert; |
| + state->sane = 1; |
| + return Z_DATA_ERROR; |
| +#endif |
| +} |
| + |
| +int ZEXPORT inflateValidate(strm, check) |
| +z_streamp strm; |
| +int check; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
| + state = (struct inflate_state FAR *)strm->state; |
| + if (check) |
| + state->wrap |= 4; |
| + else |
| + state->wrap &= ~4; |
| + return Z_OK; |
| +} |
| + |
| +long ZEXPORT inflateMark(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + |
| + if (inflateStateCheck(strm)) |
| + return -(1L << 16); |
| + state = (struct inflate_state FAR *)strm->state; |
| + return (long)(((unsigned long)((long)state->back)) << 16) + |
| + (state->mode == COPY ? state->length : |
| + (state->mode == MATCH ? state->was - state->length : 0)); |
| +} |
| + |
| +unsigned long ZEXPORT inflateCodesUsed(strm) |
| +z_streamp strm; |
| +{ |
| + struct inflate_state FAR *state; |
| + if (inflateStateCheck(strm)) return (unsigned long)-1; |
| + state = (struct inflate_state FAR *)strm->state; |
| + return (unsigned long)(state->next - state->codes); |
| +} |
| -- |
| 2.7.4 |
| |