Add brotli decompressor
This commit is for the decoder for brotli compression format.
Brotli is a generic byte-level compression algorithm.
diff --git a/brotli/LICENSE b/brotli/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/brotli/LICENSE
@@ -0,0 +1,202 @@
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diff --git a/brotli/dec/README b/brotli/dec/README
new file mode 100644
index 0000000..933bdfd
--- /dev/null
+++ b/brotli/dec/README
@@ -0,0 +1,3 @@
+This directory holds the decoder for brotli compression format.
+
+Brotli is proposed to be used at the byte-compression level in WOFF 2.0 format.
diff --git a/brotli/dec/bit_reader.c b/brotli/dec/bit_reader.c
new file mode 100644
index 0000000..858afcb
--- /dev/null
+++ b/brotli/dec/bit_reader.c
@@ -0,0 +1,122 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Bit reading helpers
+
+#include <assert.h>
+
+#include "./bit_reader.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#define MAX_NUM_BIT_READ 25
+
+#define LBITS 64 // Number of bits prefetched.
+#define WBITS 32 // Minimum number of bytes needed after
+ // BrotliFillBitWindow.
+#define LOG8_WBITS 4 // Number of bytes needed to store WBITS bits.
+
+static const uint32_t kBitMask[MAX_NUM_BIT_READ] = {
+ 0, 1, 3, 7, 15, 31, 63, 127, 255, 511, 1023, 2047, 4095, 8191, 16383, 32767,
+ 65535, 131071, 262143, 524287, 1048575, 2097151, 4194303, 8388607, 16777215
+};
+
+void BrotliInitBitReader(BrotliBitReader* const br,
+ const uint8_t* const start,
+ size_t length) {
+ size_t i;
+ assert(br != NULL);
+ assert(start != NULL);
+ assert(length < 0xfffffff8u); // can't happen with a RIFF chunk.
+
+ br->buf_ = start;
+ br->len_ = length;
+ br->val_ = 0;
+ br->pos_ = 0;
+ br->bit_pos_ = 0;
+ br->eos_ = 0;
+ br->error_ = 0;
+ for (i = 0; i < sizeof(br->val_) && i < br->len_; ++i) {
+ br->val_ |= ((uint64_t)br->buf_[br->pos_]) << (8 * i);
+ ++br->pos_;
+ }
+}
+
+void BrotliBitReaderSetBuffer(BrotliBitReader* const br,
+ const uint8_t* const buf, size_t len) {
+ assert(br != NULL);
+ assert(buf != NULL);
+ assert(len < 0xfffffff8u); // can't happen with a RIFF chunk.
+ br->eos_ = (br->pos_ >= len);
+ br->buf_ = buf;
+ br->len_ = len;
+}
+
+// If not at EOS, reload up to LBITS byte-by-byte
+static void ShiftBytes(BrotliBitReader* const br) {
+ while (br->bit_pos_ >= 8 && br->pos_ < br->len_) {
+ br->val_ >>= 8;
+ br->val_ |= ((uint64_t)br->buf_[br->pos_]) << (LBITS - 8);
+ ++br->pos_;
+ br->bit_pos_ -= 8;
+ }
+}
+
+void BrotliFillBitWindow(BrotliBitReader* const br) {
+ if (br->bit_pos_ >= WBITS) {
+#if (defined(__x86_64__) || defined(_M_X64))
+ if (br->pos_ + sizeof(br->val_) < br->len_) {
+ br->val_ >>= WBITS;
+ br->bit_pos_ -= WBITS;
+ // The expression below needs a little-endian arch to work correctly.
+ // This gives a large speedup for decoding speed.
+ br->val_ |= *(const uint64_t*)(br->buf_ + br->pos_) << (LBITS - WBITS);
+ br->pos_ += LOG8_WBITS;
+ return;
+ }
+#endif
+ ShiftBytes(br); // Slow path.
+ if (br->pos_ == br->len_ && br->bit_pos_ == LBITS) {
+ br->eos_ = 1;
+ }
+ }
+}
+
+uint32_t BrotliReadBits(BrotliBitReader* const br, int n_bits) {
+ assert(n_bits >= 0);
+ // Flag an error if end_of_stream or n_bits is more than allowed limit.
+ if (n_bits == 0 || (!br->eos_ && n_bits < MAX_NUM_BIT_READ)) {
+ const uint32_t val =
+ (uint32_t)(br->val_ >> br->bit_pos_) & kBitMask[n_bits];
+ const int new_bits = br->bit_pos_ + n_bits;
+ br->bit_pos_ = new_bits;
+ // If this read is going to cross the read buffer, set the eos flag.
+ if (br->pos_ == br->len_) {
+ if (new_bits >= LBITS) {
+ br->eos_ = 1;
+ }
+ }
+ ShiftBytes(br);
+ return val;
+ } else {
+ br->error_ = 1;
+ return 0;
+ }
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
diff --git a/brotli/dec/bit_reader.h b/brotli/dec/bit_reader.h
new file mode 100644
index 0000000..8ee16e5
--- /dev/null
+++ b/brotli/dec/bit_reader.h
@@ -0,0 +1,67 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Bit reading helpers
+
+#ifndef BROTLI_DEC_BIT_READER_H_
+#define BROTLI_DEC_BIT_READER_H_
+
+#include "./types.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+typedef struct {
+ uint64_t val_; // pre-fetched bits
+ const uint8_t* buf_; // input byte buffer
+ size_t len_; // buffer length
+ size_t pos_; // byte position in buf_
+ int bit_pos_; // current bit-reading position in val_
+ int eos_; // bitstream is finished
+ int error_; // an error occurred (buffer overflow attempt...)
+} BrotliBitReader;
+
+void BrotliInitBitReader(BrotliBitReader* const br,
+ const uint8_t* const start,
+ size_t length);
+
+// Sets a new data buffer.
+void BrotliBitReaderSetBuffer(BrotliBitReader* const br,
+ const uint8_t* const buffer, size_t length);
+
+// Reads the specified number of bits from Read Buffer.
+// Flags an error in case end_of_stream or n_bits is more than allowed limit.
+// Flags eos if this read attempt is going to cross the read buffer.
+uint32_t BrotliReadBits(BrotliBitReader* const br, int n_bits);
+
+// Return the prefetched bits, so they can be looked up.
+static BROTLI_INLINE uint32_t BrotliPrefetchBits(BrotliBitReader* const br) {
+ return (uint32_t)(br->val_ >> br->bit_pos_);
+}
+
+// For jumping over a number of bits in the bit stream when accessed with
+// BrotliPrefetchBits and BrotliFillBitWindow.
+static BROTLI_INLINE void BrotliSetBitPos(BrotliBitReader* const br, int val) {
+ br->bit_pos_ = val;
+}
+
+// Advances the Read buffer by 4 bytes to make room for reading next 32 bits.
+void BrotliFillBitWindow(BrotliBitReader* const br);
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
+
+#endif // BROTLI_DEC_BIT_READER_H_
diff --git a/brotli/dec/context.h b/brotli/dec/context.h
new file mode 100644
index 0000000..0b1abd1
--- /dev/null
+++ b/brotli/dec/context.h
@@ -0,0 +1,124 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Lookup tables to map the previous one to three bytes to a context id.
+
+#ifndef BROTLI_DEC_CONTEXT_H_
+#define BROTLI_DEC_CONTEXT_H_
+
+
+#include "./types.h"
+
+static const int kSigned2BitContextLookup[] = {
+ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3,
+};
+
+static const int kSigned3BitContextLookup[] = {
+ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
+};
+
+static const int kSigned4BitContextLookup[] = {
+ 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 14, 15,
+};
+
+enum ContextType {
+ CONTEXT_FULL = 0,
+ CONTEXT_MSB7 = 1,
+ CONTEXT_MSB6 = 2,
+ CONTEXT_MSB5 = 3,
+ CONTEXT_MSB4 = 4,
+ CONTEXT_MSB3 = 5,
+ CONTEXT_MSB2 = 6,
+ CONTEXT_MSB1 = 7,
+ CONTEXT_IS_ZERO = 8,
+ CONTEXT_SIGNED_2BIT = 9,
+ CONTEXT_SIGNED_3BIT = 10,
+ CONTEXT_SIGNED_4BIT = 11,
+ CONTEXT_SIGNED_MIXED_3BYTE = 12,
+};
+
+static const int kContextSize[] = {
+ 256, 128, 64, 32, 16, 8, 4, 2, 2, 4, 8, 16, 64,
+};
+
+static BROTLI_INLINE int NumContexts(int mode) {
+ return kContextSize[mode];
+}
+
+static BROTLI_INLINE uint8_t Context(uint8_t prev_byte, uint8_t prev_byte2,
+ uint8_t prev_byte3, int mode) {
+ switch (mode) {
+ case CONTEXT_IS_ZERO:
+ return prev_byte == 0 ? 0 : 1;
+ case CONTEXT_SIGNED_2BIT:
+ return kSigned2BitContextLookup[prev_byte];
+ case CONTEXT_SIGNED_3BIT:
+ return kSigned3BitContextLookup[prev_byte];
+ case CONTEXT_SIGNED_4BIT:
+ return kSigned4BitContextLookup[prev_byte];
+ case CONTEXT_SIGNED_MIXED_3BYTE:
+ return ((kSigned3BitContextLookup[prev_byte] << 3) +
+ (kSigned2BitContextLookup[prev_byte2] << 1) +
+ (prev_byte3 == 0 ? 0 : 1));
+ default:
+ return prev_byte >> mode;
+ }
+}
+
+#endif // BROTLI_DEC_CONTEXT_H_
diff --git a/brotli/dec/decode.c b/brotli/dec/decode.c
new file mode 100644
index 0000000..85f906a
--- /dev/null
+++ b/brotli/dec/decode.c
@@ -0,0 +1,788 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "./bit_reader.h"
+#include "./context.h"
+#include "./decode.h"
+#include "./huffman.h"
+#include "./prefix.h"
+#include "./safe_malloc.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#ifdef BROTLI_DECODE_DEBUG
+#define BROTLI_LOG_UINT(name) \
+ printf("[%s] %s = %zd\n", __func__, #name, (size_t)name)
+#define BROTLI_LOG_ARRAY_INDEX(array_name, idx) \
+ printf("[%s] %s[%zd] = %zd\n", __func__, #array_name, \
+ (size_t)idx, (size_t)array_name[idx])
+#else
+#define BROTLI_LOG_UINT(name)
+#define BROTLI_LOG_ARRAY_INDEX(array_name, idx)
+#endif
+
+static const int kDefaultCodeLength = 8;
+static const int kCodeLengthLiterals = 16;
+static const int kCodeLengthRepeatCode = 16;
+static const int kCodeLengthExtraBits[3] = { 2, 3, 7 };
+static const int kCodeLengthRepeatOffsets[3] = { 3, 3, 11 };
+
+static const int kNumLiteralCodes = 256;
+static const int kNumInsertAndCopyCodes = 704;
+static const int kNumBlockLengthCodes = 26;
+
+#define CODE_LENGTH_CODES 19
+static const uint8_t kCodeLengthCodeOrder[CODE_LENGTH_CODES] = {
+ 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+};
+
+#define NUM_DISTANCE_SHORT_CODES 16
+static const int kDistanceShortCodeIndexOffset[NUM_DISTANCE_SHORT_CODES] = {
+ 3, 2, 1, 0, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2
+};
+
+static const int kDistanceShortCodeValueOffset[NUM_DISTANCE_SHORT_CODES] = {
+ 0, 0, 0, 0, -1, 1, -2, 2, -3, 3, -1, 1, -2, 2, -3, 3
+};
+
+static int DecodeSize(BrotliBitReader* br, size_t* len) {
+ int size_bytes = BrotliReadBits(br, 3);
+ *len = 0;
+ int i = 0;
+ for (; i < size_bytes; ++i) {
+ *len |= BrotliReadBits(br, 8) << (i * 8);
+ }
+ return !br->error_;
+}
+
+static int DecodeMetaBlockLength(int input_size_bits,
+ size_t remaining_length,
+ BrotliBitReader* br,
+ size_t* meta_block_length) {
+ if (BrotliReadBits(br, 1)) {
+ *meta_block_length = remaining_length;
+ return 1;
+ }
+ *meta_block_length = 0;
+ int shift = 0;
+ while (input_size_bits > 0) {
+ *meta_block_length |= BrotliReadBits(br, 8) << shift;
+ input_size_bits -= 8;
+ shift += 8;
+ }
+ if (input_size_bits > 0) {
+ *meta_block_length |= BrotliReadBits(br, input_size_bits) << shift;
+ }
+ ++(*meta_block_length);
+ return !br->error_;
+}
+
+// Decodes the next Huffman code from bit-stream.
+// FillBitWindow(br) needs to be called at minimum every second call
+// to ReadSymbol, in order to pre-fetch enough bits.
+static BROTLI_INLINE int ReadSymbol(const HuffmanTree* tree,
+ BrotliBitReader* br) {
+ if (tree->fixed_bit_length_ > 0) {
+ return BrotliReadBits(br, tree->fixed_bit_length_);
+ }
+ const HuffmanTreeNode* node = tree->root_;
+ uint32_t bits = BrotliPrefetchBits(br);
+ int bitpos = br->bit_pos_;
+ // Check if we find the bit combination from the Huffman lookup table.
+ const int lut_ix = bits & (HUFF_LUT - 1);
+ const int lut_bits = tree->lut_bits_[lut_ix];
+ if (lut_bits <= HUFF_LUT_BITS) {
+ BrotliSetBitPos(br, bitpos + lut_bits);
+ return tree->lut_symbol_[lut_ix];
+ }
+ node += tree->lut_jump_[lut_ix];
+ bitpos += HUFF_LUT_BITS;
+ bits >>= HUFF_LUT_BITS;
+
+ // Decode the value from a binary tree.
+ assert(node != NULL);
+ do {
+ node = HuffmanTreeNextNode(node, bits & 1);
+ bits >>= 1;
+ ++bitpos;
+ } while (HuffmanTreeNodeIsNotLeaf(node));
+ BrotliSetBitPos(br, bitpos);
+ return node->symbol_;
+}
+
+static void PrintIntVector(const int* v, int len) {
+ while (len-- > 0) printf(" %d", *v++);
+ printf("\n");
+}
+
+static int ReadHuffmanCodeLengths(
+ const int* code_length_code_lengths,
+ int num_symbols, int* code_lengths,
+ BrotliBitReader* br) {
+ int ok = 0;
+ int symbol;
+ int max_symbol;
+ int prev_code_len = kDefaultCodeLength;
+ HuffmanTree tree;
+
+ if (!HuffmanTreeBuildImplicit(&tree, code_length_code_lengths,
+ CODE_LENGTH_CODES)) {
+ printf("[ReadHuffmanCodeLengths] Building code length tree failed: ");
+ PrintIntVector(code_length_code_lengths, CODE_LENGTH_CODES);
+ return 0;
+ }
+
+ int use_length = BrotliReadBits(br, 1);
+ BROTLI_LOG_UINT(use_length);
+ if (use_length) {
+ const int length_nbits = 2 + 2 * BrotliReadBits(br, 3);
+ max_symbol = 2 + BrotliReadBits(br, length_nbits);
+ BROTLI_LOG_UINT(length_nbits);
+ if (max_symbol > num_symbols) {
+ printf("[ReadHuffmanCodeLengths] max_symbol > num_symbols (%d vs %d)\n",
+ max_symbol, num_symbols);
+ goto End;
+ }
+ } else {
+ max_symbol = num_symbols;
+ }
+ BROTLI_LOG_UINT(max_symbol);
+
+ symbol = 0;
+ while (symbol < num_symbols) {
+ int code_len;
+ if (max_symbol-- == 0) break;
+ BrotliFillBitWindow(br);
+ code_len = ReadSymbol(&tree, br);
+ BROTLI_LOG_UINT(symbol);
+ BROTLI_LOG_UINT(code_len);
+ if (code_len < kCodeLengthLiterals) {
+ code_lengths[symbol++] = code_len;
+ if (code_len != 0) prev_code_len = code_len;
+ } else {
+ const int use_prev = (code_len == kCodeLengthRepeatCode);
+ const int slot = code_len - kCodeLengthLiterals;
+ const int extra_bits = kCodeLengthExtraBits[slot];
+ const int repeat_offset = kCodeLengthRepeatOffsets[slot];
+ const int length = use_prev ? prev_code_len : 0;
+ int repeat = BrotliReadBits(br, extra_bits) + repeat_offset;
+ BROTLI_LOG_UINT(repeat);
+ BROTLI_LOG_UINT(length);
+ if (symbol + repeat > num_symbols) {
+ printf("[ReadHuffmanCodeLengths] symbol + repeat > num_symbols "
+ "(%d + %d vs %d)\n", symbol, repeat, num_symbols);
+ goto End;
+ } else {
+ while (repeat-- > 0) {
+ code_lengths[symbol++] = length;
+ }
+ }
+ }
+ }
+ while (symbol < num_symbols) code_lengths[symbol++] = 0;
+ ok = 1;
+
+ End:
+ HuffmanTreeRelease(&tree);
+ return ok;
+}
+
+static const int64_t kUnitInterval = 1LL<<30;
+
+static int RepairHuffmanCodeLengths(int num_symbols, int* code_lengths) {
+ int i;
+ int64_t space = kUnitInterval;
+ int max_length = 0;
+ for(i = 0; i < num_symbols; i++)
+ if (code_lengths[i] != 0) {
+ if (code_lengths[i] > max_length)
+ max_length = code_lengths[i];
+ space -= kUnitInterval >> code_lengths[i];
+ }
+ // The code which contains one symbol of length one cannot be made optimal.
+ if (max_length == 1)
+ return 1;
+ if (space < 0) {
+ int count_longest = 0;
+ for(i = 0; i < num_symbols; i++) {
+ if (code_lengths[i] == max_length)
+ count_longest++;
+ }
+ // Substitute all longest codes with sufficiently longer ones, so that all
+ // code words fit into the unit interval. Leftover space will be
+ // redistributed later.
+ space += count_longest * (kUnitInterval >> max_length);
+ if (space < 0)
+ return 0;
+ int new_length = max_length;
+ while (space < count_longest * (kUnitInterval >> new_length))
+ new_length++;
+ space -= count_longest * (kUnitInterval >> new_length);
+ for(i = 0; i < num_symbols; i++) {
+ if (code_lengths[i] == max_length)
+ code_lengths[i] = new_length;
+ }
+ }
+
+ while (space > 0) {
+ // Redistribute leftover space in an approximation of a uniform fashion.
+ for(i = 0; i < num_symbols; i++) {
+ if (code_lengths[i] > 1 && space >= (kUnitInterval >> code_lengths[i])) {
+ space -= kUnitInterval >> code_lengths[i];
+ code_lengths[i]--;
+ }
+ if (space == 0)
+ break;
+ }
+ }
+ return 1;
+}
+
+static int ReadHuffmanCode(int alphabet_size,
+ HuffmanTree* tree,
+ BrotliBitReader* br) {
+ int ok = 0;
+ const int simple_code = BrotliReadBits(br, 1);
+ BROTLI_LOG_UINT(simple_code);
+
+ if (simple_code) { // Read symbols, codes & code lengths directly.
+ int symbols[2] = { 0 };
+ int codes[2];
+ int code_lengths[2];
+ const int num_symbols = BrotliReadBits(br, 1) + 1;
+ const int first_symbol_len_code = BrotliReadBits(br, 1);
+ // The first code is either 1 bit or 8 bit code.
+ symbols[0] = BrotliReadBits(br, (first_symbol_len_code == 0) ? 1 : 8);
+ codes[0] = 0;
+ code_lengths[0] = num_symbols - 1;
+ // The second code (if present), is always 8 bit long.
+ if (num_symbols == 2) {
+ symbols[1] = BrotliReadBits(br, 8);
+ codes[1] = 1;
+ code_lengths[1] = num_symbols - 1;
+ }
+ BROTLI_LOG_UINT(num_symbols);
+ BROTLI_LOG_UINT(first_symbol_len_code);
+ BROTLI_LOG_UINT(symbols[0]);
+ BROTLI_LOG_UINT(symbols[1]);
+ ok = HuffmanTreeBuildExplicit(tree, code_lengths, codes, symbols,
+ alphabet_size, num_symbols);
+ if (!ok) {
+ printf("[ReadHuffmanCode] HuffmanTreeBuildExplicit failed: ");
+ PrintIntVector(code_lengths, num_symbols);
+ }
+ } else { // Decode Huffman-coded code lengths.
+ int* code_lengths = NULL;
+ int i;
+ int code_length_code_lengths[CODE_LENGTH_CODES] = { 0 };
+ const int num_codes = BrotliReadBits(br, 4) + 4;
+ BROTLI_LOG_UINT(num_codes);
+ if (num_codes > CODE_LENGTH_CODES) {
+ return 0;
+ }
+
+ code_lengths =
+ (int*)BrotliSafeMalloc((uint64_t)alphabet_size, sizeof(*code_lengths));
+ if (code_lengths == NULL) {
+ return 0;
+ }
+
+ for (i = 0; i < num_codes; ++i) {
+ int code_len_idx = kCodeLengthCodeOrder[i];
+ code_length_code_lengths[code_len_idx] = BrotliReadBits(br, 3);
+ BROTLI_LOG_ARRAY_INDEX(code_length_code_lengths, code_len_idx);
+ }
+ ok = ReadHuffmanCodeLengths(code_length_code_lengths, alphabet_size,
+ code_lengths, br) &&
+ RepairHuffmanCodeLengths(alphabet_size, code_lengths);
+ if (ok) {
+ ok = HuffmanTreeBuildImplicit(tree, code_lengths, alphabet_size);
+ if (!ok) {
+ printf("[ReadHuffmanCode] HuffmanTreeBuildImplicit failed: ");
+ PrintIntVector(code_lengths, alphabet_size);
+ }
+ }
+ free(code_lengths);
+ }
+ ok = ok && !br->error_;
+ if (!ok) {
+ return 0;
+ }
+ return 1;
+}
+
+static int ReadCopyDistance(const HuffmanTree* tree,
+ int num_direct_codes,
+ int postfix_bits,
+ uint32_t postfix_mask,
+ BrotliBitReader* br) {
+ BrotliFillBitWindow(br);
+ int code = ReadSymbol(tree, br);
+ if (code < num_direct_codes) {
+ return code;
+ }
+ code -= num_direct_codes;
+ int postfix = code & postfix_mask;
+ code >>= postfix_bits;
+ int nbits = (code >> 1) + 1;
+ int offset = ((2 + (code & 1)) << nbits) - 4;
+ return (num_direct_codes +
+ ((offset + BrotliReadBits(br, nbits)) << postfix_bits) +
+ postfix);
+}
+
+static int ReadBlockLength(const HuffmanTree* tree, BrotliBitReader* br) {
+ BrotliFillBitWindow(br);
+ int code = ReadSymbol(tree, br);
+ int nbits = kBlockLengthPrefixCode[code].nbits;
+ return kBlockLengthPrefixCode[code].offset + BrotliReadBits(br, nbits);
+}
+
+static void ReadInsertAndCopy(const HuffmanTree* tree,
+ int* insert_len,
+ int* copy_len,
+ int* copy_dist,
+ BrotliBitReader* br) {
+ BrotliFillBitWindow(br);
+ int code = ReadSymbol(tree, br);
+ int range_idx = code >> 6;
+ if (range_idx >= 2) {
+ range_idx -= 2;
+ *copy_dist = -1;
+ } else {
+ *copy_dist = 0;
+ }
+ int insert_code = (kInsertRangeLut[range_idx] << 3) + ((code >> 3) & 7);
+ int copy_code = (kCopyRangeLut[range_idx] << 3) + (code & 7);
+ *insert_len =
+ kInsertLengthPrefixCode[insert_code].offset +
+ BrotliReadBits(br, kInsertLengthPrefixCode[insert_code].nbits);
+ *copy_len =
+ kCopyLengthPrefixCode[copy_code].offset +
+ BrotliReadBits(br, kCopyLengthPrefixCode[copy_code].nbits);
+}
+
+static int TranslateShortCodes(int code, int* ringbuffer, size_t* index) {
+ int val;
+ if (code < NUM_DISTANCE_SHORT_CODES) {
+ val = code;
+ int index_offset = kDistanceShortCodeIndexOffset[val];
+ int value_offset = kDistanceShortCodeValueOffset[val];
+ val = ringbuffer[(*index + index_offset) & 3] + value_offset;
+ } else {
+ val = code - NUM_DISTANCE_SHORT_CODES + 1;
+ }
+ if (code > 0) {
+ ringbuffer[*index & 3] = val;
+ ++(*index);
+ }
+ return val;
+}
+
+static void MoveToFront(uint8_t* v, uint8_t index) {
+ uint8_t value = v[index];
+ uint8_t i = index;
+ for (; i; --i) v[i] = v[i - 1];
+ v[0] = value;
+}
+
+static void InverseMoveToFrontTransform(uint8_t* v, int v_len) {
+ uint8_t mtf[256];
+ int i;
+ for (i = 0; i < 256; ++i) {
+ mtf[i] = i;
+ }
+ for (i = 0; i < v_len; ++i) {
+ uint8_t index = v[i];
+ v[i] = mtf[index];
+ if (index) MoveToFront(mtf, index);
+ }
+}
+
+// Contains a collection of huffman trees with the same alphabet size.
+typedef struct {
+ int alphabet_size;
+ int num_htrees;
+ HuffmanTree* htrees;
+} HuffmanTreeGroup;
+
+void HuffmanTreeGroupInit(HuffmanTreeGroup* group, int alphabet_size,
+ int ntrees) {
+ group->alphabet_size = alphabet_size;
+ group->num_htrees = ntrees;
+ group->htrees = (HuffmanTree*)malloc(sizeof(HuffmanTree) * ntrees);
+}
+
+void HuffmanTreeGroupRelease(HuffmanTreeGroup* group) {
+ int i;
+ for (i = 0; i < group->num_htrees; ++i) {
+ HuffmanTreeRelease(&group->htrees[i]);
+ }
+ free(group->htrees);
+}
+
+int HuffmanTreeGroupDecode(HuffmanTreeGroup* group, BrotliBitReader* br) {
+ int i;
+ for (i = 0; i < group->num_htrees; ++i) {
+ ReadHuffmanCode(group->alphabet_size, &group->htrees[i], br);
+ }
+ return 1;
+}
+
+int DecodeContextMap(int num_block_types,
+ int stream_type,
+ int* context_mode,
+ int* contexts_per_block,
+ int* num_htrees,
+ uint8_t** context_map,
+ BrotliBitReader* br) {
+ int use_context = BrotliReadBits(br, 1);
+ if (!use_context) {
+ *context_mode = 0;
+ *contexts_per_block = 1;
+ *context_map = NULL;
+ *num_htrees = num_block_types;
+ return 1;
+ }
+ switch (stream_type) {
+ case 0:
+ *context_mode = BrotliReadBits(br, 4);
+ *contexts_per_block = NumContexts(*context_mode);
+ break;
+ case 2:
+ *context_mode = 1;
+ *contexts_per_block = 4;
+ break;
+ }
+ int context_map_size = *contexts_per_block * num_block_types;
+ *num_htrees = BrotliReadBits(br, 8) + 1;
+
+ BROTLI_LOG_UINT(*context_mode);
+ BROTLI_LOG_UINT(context_map_size);
+ BROTLI_LOG_UINT(*num_htrees);
+
+ *context_map = (uint8_t*)malloc(context_map_size);
+ if (*num_htrees <= 1) {
+ memset(*context_map, 0, context_map_size);
+ return 1;
+ }
+
+ int i;
+ if (*num_htrees == context_map_size) {
+ for (i = 0; i < context_map_size; ++i) {
+ (*context_map)[i] = i;
+ }
+ return 1;
+ }
+ int use_rle_for_zeros = BrotliReadBits(br, 1);
+ int max_run_length_prefix = 0;
+ if (use_rle_for_zeros) {
+ max_run_length_prefix = BrotliReadBits(br, 4) + 1;
+ }
+ HuffmanTree tree_index_htree;
+ ReadHuffmanCode(*num_htrees + max_run_length_prefix,
+ &tree_index_htree, br);
+ if (use_rle_for_zeros) {
+ for (i = 0; i < context_map_size;) {
+ BrotliFillBitWindow(br);
+ int code = ReadSymbol(&tree_index_htree, br);
+ if (code == 0) {
+ (*context_map)[i] = 0;
+ ++i;
+ } else if (code <= max_run_length_prefix) {
+ int reps = 1 + (1 << code) + BrotliReadBits(br, code);
+ while (--reps) {
+ (*context_map)[i] = 0;
+ ++i;
+ }
+ } else {
+ (*context_map)[i] = code - max_run_length_prefix;
+ ++i;
+ }
+ }
+ } else {
+ for (i = 0; i < context_map_size; ++i) {
+ BrotliFillBitWindow(br);
+ (*context_map)[i] = ReadSymbol(&tree_index_htree, br);
+ }
+ }
+ HuffmanTreeRelease(&tree_index_htree);
+ if (BrotliReadBits(br, 1)) {
+ InverseMoveToFrontTransform(*context_map, context_map_size);
+ }
+ return 1;
+}
+
+static BROTLI_INLINE void DecodeBlockType(const HuffmanTree* trees,
+ int tree_type,
+ int* block_types,
+ int* ringbuffers,
+ size_t* indexes,
+ BrotliBitReader* br) {
+ int* ringbuffer = ringbuffers + tree_type * 2;
+ size_t* index = indexes + tree_type;
+ int type_code = ReadSymbol(trees + tree_type, br);
+ int block_type;
+ if (type_code == 0) {
+ block_type = ringbuffer[*index & 1];
+ } else if (type_code == 1) {
+ block_type = ringbuffer[(*index - 1) & 1] + 1;
+ } else {
+ block_type = type_code - 2;
+ }
+ block_types[tree_type] = block_type;
+ ringbuffer[(*index) & 1] = block_type;
+ ++(*index);
+}
+
+int BrotliDecompressedSize(size_t encoded_size,
+ const uint8_t* encoded_buffer,
+ size_t* decoded_size) {
+ BrotliBitReader br;
+ BrotliInitBitReader(&br, encoded_buffer, encoded_size);
+ return DecodeSize(&br, decoded_size);
+}
+
+int BrotliDecompressBuffer(size_t encoded_size,
+ const uint8_t* encoded_buffer,
+ size_t* decoded_size,
+ uint8_t* decoded_buffer) {
+ BrotliBitReader br;
+ BrotliInitBitReader(&br, encoded_buffer, encoded_size);
+
+ int ok = DecodeSize(&br, decoded_size);
+ if (!ok) return 0;
+
+ if (*decoded_size == 0) {
+ return 1;
+ }
+ size_t n = *decoded_size;
+ int input_size_bits = (n == (n &~ (n - 1))) ? -1 : 0;
+ while (n) {
+ ++input_size_bits;
+ n >>= 1;
+ }
+
+ BROTLI_LOG_UINT(*decoded_size);
+ BROTLI_LOG_UINT(input_size_bits);
+
+ int i;
+ size_t pos = 0;
+ const size_t end = *decoded_size;
+ uint8_t* data = decoded_buffer;
+ // This ring buffer holds a few past copy distances that will be used by
+ // some special distance codes.
+ int dist_rb[4] = { 4, 11, 15, 16 };
+ size_t dist_rb_idx = 0;
+ HuffmanTreeGroup hgroup[3];
+
+ while (pos < end && ok) {
+ BROTLI_LOG_UINT(pos);
+ size_t meta_block_len = 0;
+ if (!DecodeMetaBlockLength(input_size_bits, end - pos,
+ &br, &meta_block_len)) {
+ printf("Could not decode meta-block length.\n");
+ ok = 0;
+ goto End;
+ }
+ BROTLI_LOG_UINT(meta_block_len);
+ size_t meta_block_end = pos + meta_block_len;
+ size_t block_length[3] = { 0 };
+ int block_type[3] = { 0 };
+ int num_block_types[3] = { 0 };
+ int block_type_rb[6] = { 0, 1, 0, 1, 0, 1 };
+ size_t block_type_rb_index[3] = { 0 };
+ HuffmanTree block_type_trees[3];
+ HuffmanTree block_len_trees[3];
+ for (i = 0; i < 3; ++i) {
+ block_type_trees[i].root_ = NULL;
+ block_len_trees[i].root_ = NULL;
+ if (BrotliReadBits(&br, 1)) {
+ num_block_types[i] = BrotliReadBits(&br, 8) + 1;
+ ReadHuffmanCode(num_block_types[i] + 2, &block_type_trees[i], &br);
+ ReadHuffmanCode(kNumBlockLengthCodes, &block_len_trees[i], &br);
+ block_length[i] = ReadBlockLength(&block_len_trees[i], &br);
+ block_type_rb_index[i] = 1;
+ } else {
+ num_block_types[i] = 1;
+ block_length[i] = meta_block_len;
+ }
+ }
+
+ BROTLI_LOG_UINT(num_block_types[0]);
+ BROTLI_LOG_UINT(num_block_types[1]);
+ BROTLI_LOG_UINT(num_block_types[2]);
+ BROTLI_LOG_UINT(block_length[0]);
+ BROTLI_LOG_UINT(block_length[1]);
+ BROTLI_LOG_UINT(block_length[2]);
+
+ int distance_postfix_bits = BrotliReadBits(&br, 2);
+ int num_direct_distance_codes =
+ NUM_DISTANCE_SHORT_CODES +
+ (BrotliReadBits(&br, 4) << distance_postfix_bits);
+ uint32_t distance_postfix_mask = (1 << distance_postfix_bits) - 1;
+ int num_distance_codes = (num_direct_distance_codes +
+ (48 << distance_postfix_bits));
+ BROTLI_LOG_UINT(num_direct_distance_codes);
+ BROTLI_LOG_UINT(distance_postfix_bits);
+
+ uint8_t* context_map;
+ int context_mode;
+ int contexts_per_block;
+ int num_literal_htrees;
+ DecodeContextMap(num_block_types[0], 0, &context_mode, &contexts_per_block,
+ &num_literal_htrees, &context_map, &br);
+
+ uint8_t* dist_context_map;
+ int dist_context_mode;
+ int dist_contexts_per_block;
+ int num_dist_htrees;
+ DecodeContextMap(num_block_types[2], 2, &dist_context_mode,
+ &dist_contexts_per_block,
+ &num_dist_htrees, &dist_context_map, &br);
+
+ HuffmanTreeGroupInit(&hgroup[0], kNumLiteralCodes, num_literal_htrees);
+ HuffmanTreeGroupInit(&hgroup[1], kNumInsertAndCopyCodes,
+ num_block_types[1]);
+ HuffmanTreeGroupInit(&hgroup[2], num_distance_codes, num_dist_htrees);
+
+ for (i = 0; i < 3; ++i) {
+ HuffmanTreeGroupDecode(&hgroup[i], &br);
+ }
+
+ HuffmanTree* literal_htrees = hgroup[0].htrees;
+ int context_offset = 0;
+ uint8_t* context_map_slice = context_map;
+ uint8_t literal_htree_index = 0;
+ int dist_context_offset = 0;
+ uint8_t* dist_context_map_slice = dist_context_map;
+ uint8_t dist_htree_index = 0;
+
+ while (pos < meta_block_end) {
+ if (block_length[1] == 0) {
+ DecodeBlockType(block_type_trees, 1, block_type, block_type_rb,
+ block_type_rb_index, &br);
+ block_length[1] = ReadBlockLength(&block_len_trees[1], &br);
+ }
+ --block_length[1];
+ int insert_length;
+ int copy_length;
+ int distance_code;
+ ReadInsertAndCopy(&hgroup[1].htrees[block_type[1]],
+ &insert_length, ©_length, &distance_code, &br);
+ BROTLI_LOG_UINT(insert_length);
+ BROTLI_LOG_UINT(copy_length);
+ BROTLI_LOG_UINT(distance_code);
+ int j;
+ for (j = 0; j < insert_length; ++j) {
+ if (block_length[0] == 0) {
+ DecodeBlockType(block_type_trees, 0, block_type, block_type_rb,
+ block_type_rb_index, &br);
+ block_length[0] = ReadBlockLength(&block_len_trees[0], &br);
+ literal_htree_index = block_type[0];
+ context_offset = block_type[0] * contexts_per_block;
+ context_map_slice = context_map + context_offset;
+ }
+ --block_length[0];
+ BrotliFillBitWindow(&br);
+ // Figure out htree
+ if (contexts_per_block > 1) {
+ uint8_t prev_byte = pos > 0 ? data[pos - 1] : 0;
+ uint8_t prev_byte2 = pos > 1 ? data[pos - 2] : 0;
+ uint8_t prev_byte3 = pos > 2 ? data[pos - 3] : 0;
+ uint8_t context = Context(prev_byte, prev_byte2, prev_byte3,
+ context_mode);
+ BROTLI_LOG_UINT(context);
+ literal_htree_index = context_map_slice[context];
+ }
+ data[pos] = ReadSymbol(&literal_htrees[literal_htree_index], &br);
+ BROTLI_LOG_UINT(literal_htree_index);
+ BROTLI_LOG_ARRAY_INDEX(data, pos);
+ ++pos;
+ }
+ if (br.error_) {
+ printf("Read error after decoding literal sequence.\n");
+ ok = 0;
+ goto End;
+ }
+
+ if (pos == meta_block_end) break;
+
+ if (distance_code < 0) {
+ if (block_length[2] == 0) {
+ DecodeBlockType(block_type_trees, 2, block_type, block_type_rb,
+ block_type_rb_index, &br);
+ block_length[2] = ReadBlockLength(&block_len_trees[2], &br);
+ dist_htree_index = block_type[2];
+ dist_context_offset = block_type[2] * dist_contexts_per_block;
+ dist_context_map_slice = dist_context_map + dist_context_offset;
+ }
+ --block_length[2];
+ if (dist_contexts_per_block > 1) {
+ uint8_t context = copy_length > 4 ? 3 : copy_length - 2;
+ dist_htree_index = dist_context_map_slice[context];
+ }
+ distance_code = ReadCopyDistance(&hgroup[2].htrees[dist_htree_index],
+ num_direct_distance_codes,
+ distance_postfix_bits,
+ distance_postfix_mask,
+ &br);
+ if (br.error_) {
+ printf("Could not read copy distance.\n");
+ ok = 0;
+ goto End;
+ }
+ }
+
+ // Convert the distance code to the actual distance by possibly looking
+ // up past distnaces from the ringbuffer.
+ int dist = TranslateShortCodes(distance_code, dist_rb, &dist_rb_idx);
+ BROTLI_LOG_UINT(dist);
+
+ // Do the actual copy if it is valid.
+ if (pos >= dist && pos + copy_length <= end) {
+ int j;
+ for (j = 0; j < copy_length; ++j) {
+ data[pos + j] = data[pos + j - dist];
+ }
+ pos += copy_length;
+ } else {
+ printf("Invalid backward reference. pos: %zd dist: %d "
+ "len: %d end:%zd\n",
+ pos, dist, copy_length, end);
+ ok = 0;
+ goto End;
+ }
+ }
+ End:
+ free(context_map);
+ free(dist_context_map);
+ for (i = 0; i < 3; ++i) {
+ HuffmanTreeGroupRelease(&hgroup[i]);
+ HuffmanTreeRelease(&block_type_trees[i]);
+ HuffmanTreeRelease(&block_len_trees[i]);
+ }
+ }
+
+ return ok;
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
diff --git a/brotli/dec/decode.h b/brotli/dec/decode.h
new file mode 100644
index 0000000..6d63e3a
--- /dev/null
+++ b/brotli/dec/decode.h
@@ -0,0 +1,46 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// API for Brotli decompression
+
+#ifndef BROTLI_DEC_DECODE_H_
+#define BROTLI_DEC_DECODE_H_
+
+#include "./types.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+// Sets *decoded_size to the decompressed size of the given encoded stream.
+// Returns 1 on success, 0 on failure.
+int BrotliDecompressedSize(size_t encoded_size,
+ const uint8_t* encoded_buffer,
+ size_t* decoded_size);
+
+// Decompresses the data in encoded_buffer into decoded_buffer, and sets
+// *decoded_size to the decompressed length.
+// Returns 0 if there was either a bit stream error or memory allocation error,
+// and 1 otherwise.
+// If decoded size is zero, returns 1 and keeps decoded_buffer unchanged.
+int BrotliDecompressBuffer(size_t encoded_size,
+ const uint8_t* encoded_buffer,
+ size_t* decoded_size,
+ uint8_t* decoded_buffer);
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
+
+#endif // BROTLI_DEC_DECODE_H_
diff --git a/brotli/dec/huffman.c b/brotli/dec/huffman.c
new file mode 100644
index 0000000..5f37df4
--- /dev/null
+++ b/brotli/dec/huffman.c
@@ -0,0 +1,299 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Utilities for building and looking up Huffman trees.
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include "./huffman.h"
+#include "./safe_malloc.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+// Uncomment the following to use look-up table for ReverseBits()
+// (might be faster on some platform)
+// #define USE_LUT_REVERSE_BITS
+
+#define NON_EXISTENT_SYMBOL (-1)
+#define MAX_ALLOWED_CODE_LENGTH 15
+
+static void TreeNodeInit(HuffmanTreeNode* const node) {
+ node->children_ = -1; // means: 'unassigned so far'
+}
+
+static int NodeIsEmpty(const HuffmanTreeNode* const node) {
+ return (node->children_ < 0);
+}
+
+static int IsFull(const HuffmanTree* const tree) {
+ return (tree->num_nodes_ == tree->max_nodes_);
+}
+
+static void AssignChildren(HuffmanTree* const tree,
+ HuffmanTreeNode* const node) {
+ HuffmanTreeNode* const children = tree->root_ + tree->num_nodes_;
+ node->children_ = (int)(children - node);
+ assert(children - node == (int)(children - node));
+ tree->num_nodes_ += 2;
+ TreeNodeInit(children + 0);
+ TreeNodeInit(children + 1);
+}
+
+static int TreeInit(HuffmanTree* const tree, int num_leaves) {
+ assert(tree != NULL);
+ tree->fixed_bit_length_ = 0;
+ if (num_leaves == 0) return 0;
+ // We allocate maximum possible nodes in the tree at once.
+ // Note that a Huffman tree is a full binary tree; and in a full binary tree
+ // with L leaves, the total number of nodes N = 2 * L - 1.
+ tree->max_nodes_ = 2 * num_leaves - 1;
+ assert(tree->max_nodes_ < (1 << 16)); // limit for the lut_jump_ table
+ tree->root_ = (HuffmanTreeNode*)BrotliSafeMalloc((uint64_t)tree->max_nodes_,
+ sizeof(*tree->root_));
+ if (tree->root_ == NULL) return 0;
+ TreeNodeInit(tree->root_); // Initialize root.
+ tree->num_nodes_ = 1;
+ memset(tree->lut_bits_, 255, sizeof(tree->lut_bits_));
+ memset(tree->lut_jump_, 0, sizeof(tree->lut_jump_));
+ return 1;
+}
+
+void HuffmanTreeRelease(HuffmanTree* const tree) {
+ if (tree != NULL) {
+ free(tree->root_);
+ tree->root_ = NULL;
+ tree->max_nodes_ = 0;
+ tree->num_nodes_ = 0;
+ }
+}
+
+int HuffmanCodeLengthsToCodes(const int* const code_lengths,
+ int code_lengths_size, int* const huff_codes) {
+ int symbol;
+ int code_len;
+ int code_length_hist[MAX_ALLOWED_CODE_LENGTH + 1] = { 0 };
+ int curr_code;
+ int next_codes[MAX_ALLOWED_CODE_LENGTH + 1] = { 0 };
+ int max_code_length = 0;
+
+ assert(code_lengths != NULL);
+ assert(code_lengths_size > 0);
+ assert(huff_codes != NULL);
+
+ // Calculate max code length.
+ for (symbol = 0; symbol < code_lengths_size; ++symbol) {
+ if (code_lengths[symbol] > max_code_length) {
+ max_code_length = code_lengths[symbol];
+ }
+ }
+ if (max_code_length > MAX_ALLOWED_CODE_LENGTH) return 0;
+
+ // Calculate code length histogram.
+ for (symbol = 0; symbol < code_lengths_size; ++symbol) {
+ ++code_length_hist[code_lengths[symbol]];
+ }
+ code_length_hist[0] = 0;
+
+ // Calculate the initial values of 'next_codes' for each code length.
+ // next_codes[code_len] denotes the code to be assigned to the next symbol
+ // of code length 'code_len'.
+ curr_code = 0;
+ next_codes[0] = -1; // Unused, as code length = 0 implies code doesn't exist.
+ for (code_len = 1; code_len <= max_code_length; ++code_len) {
+ curr_code = (curr_code + code_length_hist[code_len - 1]) << 1;
+ next_codes[code_len] = curr_code;
+ }
+
+ // Get symbols.
+ for (symbol = 0; symbol < code_lengths_size; ++symbol) {
+ if (code_lengths[symbol] > 0) {
+ huff_codes[symbol] = next_codes[code_lengths[symbol]]++;
+ } else {
+ huff_codes[symbol] = NON_EXISTENT_SYMBOL;
+ }
+ }
+ return 1;
+}
+
+#ifndef USE_LUT_REVERSE_BITS
+
+static int ReverseBitsShort(int bits, int num_bits) {
+ int retval = 0;
+ int i;
+ assert(num_bits <= 8); // Not a hard requirement, just for coherency.
+ for (i = 0; i < num_bits; ++i) {
+ retval <<= 1;
+ retval |= bits & 1;
+ bits >>= 1;
+ }
+ return retval;
+}
+
+#else
+
+static const uint8_t kReversedBits[16] = { // Pre-reversed 4-bit values.
+ 0x0, 0x8, 0x4, 0xc, 0x2, 0xa, 0x6, 0xe,
+ 0x1, 0x9, 0x5, 0xd, 0x3, 0xb, 0x7, 0xf
+};
+
+static int ReverseBitsShort(int bits, int num_bits) {
+ const uint8_t v = (kReversedBits[bits & 0xf] << 4) | kReversedBits[bits >> 4];
+ assert(num_bits <= 8);
+ return v >> (8 - num_bits);
+}
+
+#endif
+
+static int TreeAddSymbol(HuffmanTree* const tree,
+ int symbol, int code, int code_length) {
+ int step = HUFF_LUT_BITS;
+ int base_code;
+ HuffmanTreeNode* node = tree->root_;
+ const HuffmanTreeNode* const max_node = tree->root_ + tree->max_nodes_;
+ assert(symbol == (int16_t)symbol);
+ if (code_length <= HUFF_LUT_BITS) {
+ int i;
+ base_code = ReverseBitsShort(code, code_length);
+ for (i = 0; i < (1 << (HUFF_LUT_BITS - code_length)); ++i) {
+ const int idx = base_code | (i << code_length);
+ tree->lut_symbol_[idx] = (int16_t)symbol;
+ tree->lut_bits_[idx] = code_length;
+ }
+ } else {
+ base_code = ReverseBitsShort((code >> (code_length - HUFF_LUT_BITS)),
+ HUFF_LUT_BITS);
+ }
+ while (code_length-- > 0) {
+ if (node >= max_node) {
+ return 0;
+ }
+ if (NodeIsEmpty(node)) {
+ if (IsFull(tree)) return 0; // error: too many symbols.
+ AssignChildren(tree, node);
+ } else if (!HuffmanTreeNodeIsNotLeaf(node)) {
+ return 0; // leaf is already occupied.
+ }
+ node += node->children_ + ((code >> code_length) & 1);
+ if (--step == 0) {
+ tree->lut_jump_[base_code] = (int16_t)(node - tree->root_);
+ }
+ }
+ if (NodeIsEmpty(node)) {
+ node->children_ = 0; // turn newly created node into a leaf.
+ } else if (HuffmanTreeNodeIsNotLeaf(node)) {
+ return 0; // trying to assign a symbol to already used code.
+ }
+ node->symbol_ = symbol; // Add symbol in this node.
+ return 1;
+}
+
+int HuffmanTreeBuildImplicit(HuffmanTree* const tree,
+ const int* const code_lengths,
+ int code_lengths_size) {
+ int symbol;
+ int num_symbols = 0;
+ int root_symbol = 0;
+
+ assert(tree != NULL);
+ assert(code_lengths != NULL);
+
+ // Find out number of symbols and the root symbol.
+ for (symbol = 0; symbol < code_lengths_size; ++symbol) {
+ if (code_lengths[symbol] > 0) {
+ // Note: code length = 0 indicates non-existent symbol.
+ ++num_symbols;
+ root_symbol = symbol;
+ }
+ }
+
+ // Initialize the tree. Will fail for num_symbols = 0
+ if (!TreeInit(tree, num_symbols)) return 0;
+
+ // Build tree.
+ if (num_symbols == 1) { // Trivial case.
+ const int max_symbol = code_lengths_size;
+ if (root_symbol < 0 || root_symbol >= max_symbol) {
+ HuffmanTreeRelease(tree);
+ return 0;
+ }
+ return TreeAddSymbol(tree, root_symbol, 0, 0);
+ } else { // Normal case.
+ int ok = 0;
+
+ // Get Huffman codes from the code lengths.
+ int* const codes =
+ (int*)BrotliSafeMalloc((uint64_t)code_lengths_size, sizeof(*codes));
+ if (codes == NULL) goto End;
+
+ if (!HuffmanCodeLengthsToCodes(code_lengths, code_lengths_size, codes)) {
+ goto End;
+ }
+
+ // Add symbols one-by-one.
+ for (symbol = 0; symbol < code_lengths_size; ++symbol) {
+ if (code_lengths[symbol] > 0) {
+ if (!TreeAddSymbol(tree, symbol, codes[symbol], code_lengths[symbol])) {
+ goto End;
+ }
+ }
+ }
+ ok = 1;
+ End:
+ free(codes);
+ ok = ok && IsFull(tree);
+ if (!ok) HuffmanTreeRelease(tree);
+ return ok;
+ }
+}
+
+int HuffmanTreeBuildExplicit(HuffmanTree* const tree,
+ const int* const code_lengths,
+ const int* const codes,
+ const int* const symbols, int max_symbol,
+ int num_symbols) {
+ int ok = 0;
+ int i;
+
+ assert(tree != NULL);
+ assert(code_lengths != NULL);
+ assert(codes != NULL);
+ assert(symbols != NULL);
+
+ // Initialize the tree. Will fail if num_symbols = 0.
+ if (!TreeInit(tree, num_symbols)) return 0;
+
+ // Add symbols one-by-one.
+ for (i = 0; i < num_symbols; ++i) {
+ if (codes[i] != NON_EXISTENT_SYMBOL) {
+ if (symbols[i] < 0 || symbols[i] >= max_symbol) {
+ goto End;
+ }
+ if (!TreeAddSymbol(tree, symbols[i], codes[i], code_lengths[i])) {
+ goto End;
+ }
+ }
+ }
+ ok = 1;
+ End:
+ ok = ok && IsFull(tree);
+ if (!ok) HuffmanTreeRelease(tree);
+ return ok;
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
diff --git a/brotli/dec/huffman.h b/brotli/dec/huffman.h
new file mode 100644
index 0000000..2c21fdd
--- /dev/null
+++ b/brotli/dec/huffman.h
@@ -0,0 +1,91 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Utilities for building and looking up Huffman trees.
+
+#ifndef BROTLI_DEC_HUFFMAN_H_
+#define BROTLI_DEC_HUFFMAN_H_
+
+#include <assert.h>
+#include "./types.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+// A node of a Huffman tree.
+typedef struct {
+ int symbol_;
+ int children_; // delta offset to both children (contiguous) or 0 if leaf.
+} HuffmanTreeNode;
+
+// Huffman Tree.
+#define HUFF_LUT_BITS 7
+#define HUFF_LUT (1U << HUFF_LUT_BITS)
+typedef struct HuffmanTree HuffmanTree;
+struct HuffmanTree {
+ // Fast lookup for short bit lengths.
+ uint8_t lut_bits_[HUFF_LUT];
+ int16_t lut_symbol_[HUFF_LUT];
+ int16_t lut_jump_[HUFF_LUT];
+ // Complete tree for lookups.
+ HuffmanTreeNode* root_; // all the nodes, starting at root.
+ int max_nodes_; // max number of nodes
+ int num_nodes_; // number of currently occupied nodes
+ int fixed_bit_length_; // If non-zero, uses fixed length coding
+};
+
+// Returns true if the given node is not a leaf of the Huffman tree.
+static BROTLI_INLINE int HuffmanTreeNodeIsNotLeaf(
+ const HuffmanTreeNode* const node) {
+ return node->children_;
+}
+
+// Go down one level. Most critical function. 'right_child' must be 0 or 1.
+static BROTLI_INLINE const HuffmanTreeNode* HuffmanTreeNextNode(
+ const HuffmanTreeNode* node, int right_child) {
+ return node + node->children_ + right_child;
+}
+
+// Releases the nodes of the Huffman tree.
+// Note: It does NOT free 'tree' itself.
+void HuffmanTreeRelease(HuffmanTree* const tree);
+
+// Builds Huffman tree assuming code lengths are implicitly in symbol order.
+// Returns false in case of error (invalid tree or memory error).
+int HuffmanTreeBuildImplicit(HuffmanTree* const tree,
+ const int* const code_lengths,
+ int code_lengths_size);
+
+// Build a Huffman tree with explicitly given lists of code lengths, codes
+// and symbols. Verifies that all symbols added are smaller than max_symbol.
+// Returns false in case of an invalid symbol, invalid tree or memory error.
+int HuffmanTreeBuildExplicit(HuffmanTree* const tree,
+ const int* const code_lengths,
+ const int* const codes,
+ const int* const symbols, int max_symbol,
+ int num_symbols);
+
+// Utility: converts Huffman code lengths to corresponding Huffman codes.
+// 'huff_codes' should be pre-allocated.
+// Returns false in case of error (memory allocation, invalid codes).
+int HuffmanCodeLengthsToCodes(const int* const code_lengths,
+ int code_lengths_size, int* const huff_codes);
+
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
+
+#endif // BROTLI_DEC_HUFFMAN_H_
diff --git a/brotli/dec/prefix.h b/brotli/dec/prefix.h
new file mode 100644
index 0000000..dda01b1
--- /dev/null
+++ b/brotli/dec/prefix.h
@@ -0,0 +1,68 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Lookup tables to map prefix codes to value ranges. This is used during
+// decoding of the block lengths, literal insertion lengths and copy lengths.
+
+#ifndef BROTLI_DEC_PREFIX_H_
+#define BROTLI_DEC_PREFIX_H_
+
+// Represents the range of values belonging to a prefix code:
+// [offset, offset + 2^nbits)
+struct PrefixCodeRange {
+ int offset;
+ int nbits;
+};
+
+static const struct PrefixCodeRange kBlockLengthPrefixCode[] = {
+ { 1, 2}, { 5, 2}, { 9, 2}, { 13, 2},
+ { 17, 3}, { 25, 3}, { 33, 3}, { 41, 3},
+ { 49, 4}, { 65, 4}, { 81, 4}, { 97, 4},
+ { 113, 5}, { 145, 5}, { 177, 5}, { 209, 5},
+ { 241, 6}, { 305, 6}, { 369, 7}, { 497, 8},
+ { 753, 9}, { 1265, 10}, {2289, 11}, {4337, 12},
+ {8433, 13}, {16625, 24}
+};
+
+static const struct PrefixCodeRange kInsertLengthPrefixCode[] = {
+ { 0, 0}, { 1, 0}, { 2, 0}, { 3, 0},
+ { 4, 0}, { 5, 0}, { 6, 1}, { 8, 1},
+ { 10, 2}, { 14, 2}, { 18, 3}, { 26, 3},
+ { 34, 4}, { 50, 4}, { 66, 5}, { 98, 5},
+ { 130, 6}, { 194, 7}, { 322, 8}, { 578, 9},
+ {1090, 10}, {2114, 12}, {6210, 14}, {22594, 24},
+};
+
+static const struct PrefixCodeRange kCopyLengthPrefixCode[] = {
+ { 2, 0}, { 3, 0}, { 4, 0}, { 5, 0},
+ { 6, 0}, { 7, 0}, { 8, 0}, { 9, 0},
+ { 10, 1}, { 12, 1}, { 14, 2}, { 18, 2},
+ { 22, 3}, { 30, 3}, { 38, 4}, { 54, 4},
+ { 70, 5}, { 102, 5}, { 134, 6}, { 198, 7},
+ {326, 8}, { 582, 9}, {1094, 10}, {2118, 24},
+};
+
+static const int kInsertAndCopyRangeLut[9] = {
+ 0, 1, 4, 2, 3, 6, 5, 7, 8,
+};
+
+static const int kInsertRangeLut[9] = {
+ 0, 0, 1, 1, 0, 2, 1, 2, 2,
+};
+
+static const int kCopyRangeLut[9] = {
+ 0, 1, 0, 1, 2, 0, 2, 1, 2,
+};
+
+#endif // BROTLI_DEC_PREFIX_H_
diff --git a/brotli/dec/safe_malloc.c b/brotli/dec/safe_malloc.c
new file mode 100644
index 0000000..41fa480
--- /dev/null
+++ b/brotli/dec/safe_malloc.c
@@ -0,0 +1,41 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Size-checked memory allocation.
+
+#include <stdlib.h>
+#include "./safe_malloc.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+// Returns 0 in case of overflow of nmemb * size.
+static int CheckSizeArgumentsOverflow(uint64_t nmemb, size_t size) {
+ const uint64_t total_size = nmemb * size;
+ if (nmemb == 0) return 1;
+ if ((uint64_t)size > BROTLI_MAX_ALLOCABLE_MEMORY / nmemb) return 0;
+ if (total_size != (size_t)total_size) return 0;
+ return 1;
+}
+
+void* BrotliSafeMalloc(uint64_t nmemb, size_t size) {
+ if (!CheckSizeArgumentsOverflow(nmemb, size)) return NULL;
+ assert(nmemb * size > 0);
+ return malloc((size_t)(nmemb * size));
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
diff --git a/brotli/dec/safe_malloc.h b/brotli/dec/safe_malloc.h
new file mode 100644
index 0000000..5a334fc
--- /dev/null
+++ b/brotli/dec/safe_malloc.h
@@ -0,0 +1,43 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Size-checked memory allocation.
+
+#ifndef BROTLI_UTILS_UTILS_H_
+#define BROTLI_UTILS_UTILS_H_
+
+#include <assert.h>
+
+#include "./types.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+// This is the maximum memory amount that we will ever try to allocate.
+#define BROTLI_MAX_ALLOCABLE_MEMORY (1ULL << 40)
+
+// size-checking safe malloc/calloc: verify that the requested size is not too
+// large, or return NULL. You don't need to call these for constructs like
+// malloc(sizeof(foo)), but only if there's font-dependent size involved
+// somewhere (like: malloc(decoded_size * sizeof(*something))). That's why this
+// safe malloc() borrows the signature from calloc(), pointing at the dangerous
+// underlying multiply involved.
+void* BrotliSafeMalloc(uint64_t nmemb, size_t size);
+
+#if defined(__cplusplus) || defined(c_plusplus)
+} // extern "C"
+#endif
+
+#endif /* BROTLI_UTILS_UTILS_H_ */
diff --git a/brotli/dec/types.h b/brotli/dec/types.h
new file mode 100644
index 0000000..41696e4
--- /dev/null
+++ b/brotli/dec/types.h
@@ -0,0 +1,41 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Common types
+
+#ifndef BROTLI_DEC_TYPES_H_
+#define BROTLI_DEC_TYPES_H_
+
+#include <stddef.h> // for size_t
+
+#ifndef _MSC_VER
+#include <inttypes.h>
+#ifdef __STRICT_ANSI__
+#define BROTLI_INLINE
+#else /* __STRICT_ANSI__ */
+#define BROTLI_INLINE inline
+#endif
+#else
+typedef signed char int8_t;
+typedef unsigned char uint8_t;
+typedef signed short int16_t;
+typedef unsigned short uint16_t;
+typedef signed int int32_t;
+typedef unsigned int uint32_t;
+typedef unsigned long long int uint64_t;
+typedef long long int int64_t;
+#define BROTLI_INLINE __forceinline
+#endif /* _MSC_VER */
+
+#endif // BROTLI_DEC_TYPES_H_
