diff options
Diffstat (limited to 'Source/ThirdParty/brotli/dec/decode.c')
| -rw-r--r-- | Source/ThirdParty/brotli/dec/decode.c | 1302 |
1 files changed, 710 insertions, 592 deletions
diff --git a/Source/ThirdParty/brotli/dec/decode.c b/Source/ThirdParty/brotli/dec/decode.c index d184f24cb..be8de42fb 100644 --- a/Source/ThirdParty/brotli/dec/decode.c +++ b/Source/ThirdParty/brotli/dec/decode.c @@ -4,7 +4,7 @@ See file LICENSE for detail or copy at https://opensource.org/licenses/MIT */ -#include "./decode.h" +#include <brotli/decode.h> #ifdef __ARM_NEON__ #include <arm_neon.h> @@ -13,9 +13,11 @@ #include <stdlib.h> /* free, malloc */ #include <string.h> /* memcpy, memset */ +#include "../common/constants.h" +#include "../common/dictionary.h" +#include "../common/version.h" #include "./bit_reader.h" #include "./context.h" -#include "./dictionary.h" #include "./huffman.h" #include "./port.h" #include "./prefix.h" @@ -34,19 +36,15 @@ extern "C" { BROTLI_LOG(("[%s] %s[%lu] = %lu\n", __func__, #array_name, \ (unsigned long)(idx), (unsigned long)array_name[idx])) -static const uint32_t kDefaultCodeLength = 8; -static const uint32_t kCodeLengthRepeatCode = 16; -static const uint32_t kNumLiteralCodes = 256; -static const uint32_t kNumInsertAndCopyCodes = 704; -static const uint32_t kNumBlockLengthCodes = 26; -static const int kLiteralContextBits = 6; -static const int kDistanceContextBits = 2; - #define HUFFMAN_TABLE_BITS 8U #define HUFFMAN_TABLE_MASK 0xff -#define CODE_LENGTH_CODES 18 -static const uint8_t kCodeLengthCodeOrder[CODE_LENGTH_CODES] = { +/* We need the slack region for the following reasons: + - doing up to two 16-byte copies for fast backward copying + - inserting transformed dictionary word (5 prefix + 24 base + 8 suffix) */ +static const uint32_t kRingBufferWriteAheadSlack = 42; + +static const uint8_t kCodeLengthCodeOrder[BROTLI_CODE_LENGTH_CODES] = { 1, 2, 3, 4, 0, 5, 17, 6, 16, 7, 8, 9, 10, 11, 12, 13, 14, 15, }; @@ -59,46 +57,59 @@ static const uint8_t kCodeLengthPrefixValue[16] = { 0, 4, 3, 2, 0, 4, 3, 1, 0, 4, 3, 2, 0, 4, 3, 5, }; -#define NUM_DISTANCE_SHORT_CODES 16 +BROTLI_BOOL BrotliDecoderSetParameter( + BrotliDecoderState* state, BrotliDecoderParameter p, uint32_t value) { + switch (p) { + case BROTLI_DECODER_PARAM_DISABLE_RING_BUFFER_REALLOCATION: + state->canny_ringbuffer_allocation = !!value ? 0 : 1; + return BROTLI_TRUE; + + default: return BROTLI_FALSE; + } +} -BrotliState* BrotliCreateState( +BrotliDecoderState* BrotliDecoderCreateInstance( brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) { - BrotliState* state = 0; + BrotliDecoderState* state = 0; if (!alloc_func && !free_func) { - state = (BrotliState*)malloc(sizeof(BrotliState)); + state = (BrotliDecoderState*)malloc(sizeof(BrotliDecoderState)); } else if (alloc_func && free_func) { - state = (BrotliState*)alloc_func(opaque, sizeof(BrotliState)); + state = (BrotliDecoderState*)alloc_func(opaque, sizeof(BrotliDecoderState)); } if (state == 0) { BROTLI_DUMP(); return 0; } - BrotliStateInitWithCustomAllocators(state, alloc_func, free_func, opaque); - state->error_code = BROTLI_NO_ERROR; + BrotliDecoderStateInitWithCustomAllocators( + state, alloc_func, free_func, opaque); return state; } -/* Deinitializes and frees BrotliState instance. */ -void BrotliDestroyState(BrotliState* state) { +/* Deinitializes and frees BrotliDecoderState instance. */ +void BrotliDecoderDestroyInstance(BrotliDecoderState* state) { if (!state) { return; } else { brotli_free_func free_func = state->free_func; void* opaque = state->memory_manager_opaque; - BrotliStateCleanup(state); + BrotliDecoderStateCleanup(state); free_func(opaque, state); } } -/* Saves error code and converts it to BrotliResult */ -static BROTLI_NOINLINE BrotliResult SaveErrorCode( - BrotliState* s, BrotliErrorCode e) { +/* Saves error code and converts it to BrotliDecoderResult */ +static BROTLI_NOINLINE BrotliDecoderResult SaveErrorCode( + BrotliDecoderState* s, BrotliDecoderErrorCode e) { s->error_code = (int)e; switch (e) { - case BROTLI_SUCCESS: return BROTLI_RESULT_SUCCESS; - case BROTLI_NEEDS_MORE_INPUT: return BROTLI_RESULT_NEEDS_MORE_INPUT; - case BROTLI_NEEDS_MORE_OUTPUT: return BROTLI_RESULT_NEEDS_MORE_OUTPUT; - default: return BROTLI_RESULT_ERROR; + case BROTLI_DECODER_SUCCESS: + return BROTLI_DECODER_RESULT_SUCCESS; + case BROTLI_DECODER_NEEDS_MORE_INPUT: + return BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT; + case BROTLI_DECODER_NEEDS_MORE_OUTPUT: + return BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT; + default: + return BROTLI_DECODER_RESULT_ERROR; } } @@ -132,60 +143,61 @@ static BROTLI_INLINE void memmove16(uint8_t* dst, uint8_t* src) { } /* Decodes a number in the range [0..255], by reading 1 - 11 bits. */ -static BROTLI_NOINLINE BrotliErrorCode DecodeVarLenUint8(BrotliState* s, - BrotliBitReader* br, uint32_t* value) { +static BROTLI_NOINLINE BrotliDecoderErrorCode DecodeVarLenUint8( + BrotliDecoderState* s, BrotliBitReader* br, uint32_t* value) { uint32_t bits; switch (s->substate_decode_uint8) { case BROTLI_STATE_DECODE_UINT8_NONE: - if (PREDICT_FALSE(!BrotliSafeReadBits(br, 1, &bits))) { - return BROTLI_NEEDS_MORE_INPUT; + if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, 1, &bits))) { + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits == 0) { *value = 0; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* No break, transit to the next state. */ case BROTLI_STATE_DECODE_UINT8_SHORT: - if (PREDICT_FALSE(!BrotliSafeReadBits(br, 3, &bits))) { + if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, 3, &bits))) { s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_SHORT; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits == 0) { *value = 1; s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* Use output value as a temporary storage. It MUST be persisted. */ *value = bits; /* No break, transit to the next state. */ case BROTLI_STATE_DECODE_UINT8_LONG: - if (PREDICT_FALSE(!BrotliSafeReadBits(br, *value, &bits))) { + if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, *value, &bits))) { s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_LONG; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } *value = (1U << *value) + bits; s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; default: - return BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE); + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE); } } /* Decodes a metablock length and flags by reading 2 - 31 bits. */ -static BrotliErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( - BrotliState* s, BrotliBitReader* br) { +static BrotliDecoderErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( + BrotliDecoderState* s, BrotliBitReader* br) { uint32_t bits; int i; for (;;) { switch (s->substate_metablock_header) { case BROTLI_STATE_METABLOCK_HEADER_NONE: if (!BrotliSafeReadBits(br, 1, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } - s->is_last_metablock = (uint8_t)bits; + s->is_last_metablock = bits ? 1 : 0; s->meta_block_remaining_len = 0; s->is_uncompressed = 0; s->is_metadata = 0; @@ -198,18 +210,18 @@ static BrotliErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( case BROTLI_STATE_METABLOCK_HEADER_EMPTY: if (!BrotliSafeReadBits(br, 1, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits) { s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NIBBLES; /* No break, transit to the next state. */ case BROTLI_STATE_METABLOCK_HEADER_NIBBLES: if (!BrotliSafeReadBits(br, 2, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } s->size_nibbles = (uint8_t)(bits + 4); s->loop_counter = 0; @@ -223,13 +235,13 @@ static BrotliErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( case BROTLI_STATE_METABLOCK_HEADER_SIZE: i = s->loop_counter; - for (; i < s->size_nibbles; ++i) { + for (; i < (int)s->size_nibbles; ++i) { if (!BrotliSafeReadBits(br, 4, &bits)) { s->loop_counter = i; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (i + 1 == s->size_nibbles && s->size_nibbles > 4 && bits == 0) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_EXUBERANT_NIBBLE); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_NIBBLE); } s->meta_block_remaining_len |= (int)(bits << (i * 4)); } @@ -240,31 +252,31 @@ static BrotliErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( case BROTLI_STATE_METABLOCK_HEADER_UNCOMPRESSED: if (!s->is_last_metablock) { if (!BrotliSafeReadBits(br, 1, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } - s->is_uncompressed = (uint8_t)bits; + s->is_uncompressed = bits ? 1 : 0; } ++s->meta_block_remaining_len; s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; case BROTLI_STATE_METABLOCK_HEADER_RESERVED: if (!BrotliSafeReadBits(br, 1, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits != 0) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_RESERVED); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_RESERVED); } s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_BYTES; /* No break, transit to the next state. */ case BROTLI_STATE_METABLOCK_HEADER_BYTES: if (!BrotliSafeReadBits(br, 2, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits == 0) { s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } s->size_nibbles = (uint8_t)bits; s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_METADATA; @@ -272,22 +284,24 @@ static BrotliErrorCode BROTLI_NOINLINE DecodeMetaBlockLength( case BROTLI_STATE_METABLOCK_HEADER_METADATA: i = s->loop_counter; - for (; i < s->size_nibbles; ++i) { + for (; i < (int)s->size_nibbles; ++i) { if (!BrotliSafeReadBits(br, 8, &bits)) { s->loop_counter = i; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (i + 1 == s->size_nibbles && s->size_nibbles > 1 && bits == 0) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_EXUBERANT_META_NIBBLE); + return BROTLI_FAILURE( + BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE); } s->meta_block_remaining_len |= (int)(bits << (i * 8)); } ++s->meta_block_remaining_len; s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; default: - return BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE); + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE); } } } @@ -319,17 +333,16 @@ static BROTLI_INLINE uint32_t ReadSymbol(const HuffmanCode* table, /* Same as DecodeSymbol, but it is known that there is less than 15 bits of input are currently available. */ -static BROTLI_NOINLINE int SafeDecodeSymbol(const HuffmanCode* table, - BrotliBitReader* br, - uint32_t* result) { +static BROTLI_NOINLINE BROTLI_BOOL SafeDecodeSymbol( + const HuffmanCode* table, BrotliBitReader* br, uint32_t* result) { uint32_t val; uint32_t available_bits = BrotliGetAvailableBits(br); if (available_bits == 0) { if (table->bits == 0) { *result = table->value; - return 1; + return BROTLI_TRUE; } - return 0; /* No valid bits at all. */ + return BROTLI_FALSE; /* No valid bits at all. */ } val = (uint32_t)BrotliGetBitsUnmasked(br); table += val & HUFFMAN_TABLE_MASK; @@ -337,13 +350,13 @@ static BROTLI_NOINLINE int SafeDecodeSymbol(const HuffmanCode* table, if (table->bits <= available_bits) { BrotliDropBits(br, table->bits); *result = table->value; - return 1; + return BROTLI_TRUE; } else { - return 0; /* Not enough bits for the first level. */ + return BROTLI_FALSE; /* Not enough bits for the first level. */ } } if (available_bits <= HUFFMAN_TABLE_BITS) { - return 0; /* Not enough bits to move to the second level. */ + return BROTLI_FALSE; /* Not enough bits to move to the second level. */ } /* Speculatively drop HUFFMAN_TABLE_BITS. */ @@ -351,21 +364,20 @@ static BROTLI_NOINLINE int SafeDecodeSymbol(const HuffmanCode* table, available_bits -= HUFFMAN_TABLE_BITS; table += table->value + val; if (available_bits < table->bits) { - return 0; /* Not enough bits for the second level. */ + return BROTLI_FALSE; /* Not enough bits for the second level. */ } BrotliDropBits(br, HUFFMAN_TABLE_BITS + table->bits); *result = table->value; - return 1; + return BROTLI_TRUE; } -static BROTLI_INLINE int SafeReadSymbol(const HuffmanCode* table, - BrotliBitReader* br, - uint32_t* result) { +static BROTLI_INLINE BROTLI_BOOL SafeReadSymbol( + const HuffmanCode* table, BrotliBitReader* br, uint32_t* result) { uint32_t val; - if (PREDICT_TRUE(BrotliSafeGetBits(br, 15, &val))) { + if (BROTLI_PREDICT_TRUE(BrotliSafeGetBits(br, 15, &val))) { *result = DecodeSymbol(val, table, br); - return 1; + return BROTLI_TRUE; } return SafeDecodeSymbol(table, br, result); } @@ -391,7 +403,7 @@ static BROTLI_INLINE uint32_t ReadPreloadedSymbol(const HuffmanCode* table, uint32_t* bits, uint32_t* value) { uint32_t result = *value; - if (PREDICT_FALSE(*bits > HUFFMAN_TABLE_BITS)) { + if (BROTLI_PREDICT_FALSE(*bits > HUFFMAN_TABLE_BITS)) { uint32_t val = BrotliGet16BitsUnmasked(br); const HuffmanCode* ext = table + (val & HUFFMAN_TABLE_MASK) + *value; uint32_t mask = BitMask((*bits - HUFFMAN_TABLE_BITS)); @@ -419,8 +431,8 @@ static BROTLI_INLINE uint32_t Log2Floor(uint32_t x) { Totally 1..4 symbols are read, 1..10 bits each. The list of symbols MUST NOT contain duplicates. */ -static BrotliErrorCode ReadSimpleHuffmanSymbols(uint32_t alphabet_size, - BrotliState* s) { +static BrotliDecoderErrorCode ReadSimpleHuffmanSymbols( + uint32_t alphabet_size, BrotliDecoderState* s) { /* max_bits == 1..10; symbol == 0..3; 1..40 bits will be read. */ BrotliBitReader* br = &s->br; uint32_t max_bits = Log2Floor(alphabet_size - 1); @@ -428,13 +440,14 @@ static BrotliErrorCode ReadSimpleHuffmanSymbols(uint32_t alphabet_size, uint32_t num_symbols = s->symbol; while (i <= num_symbols) { uint32_t v; - if (PREDICT_FALSE(!BrotliSafeReadBits(br, max_bits, &v))) { + if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, max_bits, &v))) { s->sub_loop_counter = i; s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_READ; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (v >= alphabet_size) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET); + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET); } s->symbols_lists_array[i] = (uint16_t)v; BROTLI_LOG_UINT(s->symbols_lists_array[i]); @@ -445,19 +458,19 @@ static BrotliErrorCode ReadSimpleHuffmanSymbols(uint32_t alphabet_size, uint32_t k = i + 1; for (; k <= num_symbols; ++k) { if (s->symbols_lists_array[i] == s->symbols_lists_array[k]) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME); } } } - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* Process single decoded symbol code length: A) reset the repeat variable B) remember code length (if it is not 0) - C) extend corredponding index-chain - D) reduce the huffman space + C) extend corresponding index-chain + D) reduce the Huffman space E) update the histogram */ static BROTLI_INLINE void ProcessSingleCodeLength(uint32_t code_len, @@ -478,12 +491,14 @@ static BROTLI_INLINE void ProcessSingleCodeLength(uint32_t code_len, /* Process repeated symbol code length. A) Check if it is the extension of previous repeat sequence; if the decoded - value is not kCodeLengthRepeatCode, then it is a new symbol-skip + value is not BROTLI_REPEAT_PREVIOUS_CODE_LENGTH, then it is a new + symbol-skip B) Update repeat variable - C) Check if operation is feasible (fits alphapet) + C) Check if operation is feasible (fits alphabet) D) For each symbol do the same operations as in ProcessSingleCodeLength - PRECONDITION: code_len == kCodeLengthRepeatCode or kCodeLengthRepeatCode + 1 + PRECONDITION: code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH or + code_len == BROTLI_REPEAT_ZERO_CODE_LENGTH */ static BROTLI_INLINE void ProcessRepeatedCodeLength(uint32_t code_len, uint32_t repeat_delta, uint32_t alphabet_size, uint32_t* symbol, @@ -491,9 +506,11 @@ static BROTLI_INLINE void ProcessRepeatedCodeLength(uint32_t code_len, uint32_t* repeat_code_len, uint16_t* symbol_lists, uint16_t* code_length_histo, int* next_symbol) { uint32_t old_repeat; - uint32_t new_len = 0; - if (code_len == kCodeLengthRepeatCode) { + uint32_t extra_bits = 3; /* for BROTLI_REPEAT_ZERO_CODE_LENGTH */ + uint32_t new_len = 0; /* for BROTLI_REPEAT_ZERO_CODE_LENGTH */ + if (code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) { new_len = *prev_code_len; + extra_bits = 2; } if (*repeat_code_len != new_len) { *repeat = 0; @@ -502,7 +519,7 @@ static BROTLI_INLINE void ProcessRepeatedCodeLength(uint32_t code_len, old_repeat = *repeat; if (*repeat > 0) { *repeat -= 2; - *repeat <<= code_len - 14U; + *repeat <<= extra_bits; } *repeat += repeat_delta + 3U; repeat_delta = *repeat - old_repeat; @@ -531,8 +548,8 @@ static BROTLI_INLINE void ProcessRepeatedCodeLength(uint32_t code_len, } /* Reads and decodes symbol codelengths. */ -static BrotliErrorCode ReadSymbolCodeLengths( - uint32_t alphabet_size, BrotliState* s) { +static BrotliDecoderErrorCode ReadSymbolCodeLengths( + uint32_t alphabet_size, BrotliDecoderState* s) { BrotliBitReader* br = &s->br; uint32_t symbol = s->symbol; uint32_t repeat = s->repeat; @@ -543,7 +560,7 @@ static BrotliErrorCode ReadSymbolCodeLengths( uint16_t* code_length_histo = s->code_length_histo; int* next_symbol = s->next_symbol; if (!BrotliWarmupBitReader(br)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } while (symbol < alphabet_size && space > 0) { const HuffmanCode* p = s->table; @@ -554,44 +571,53 @@ static BrotliErrorCode ReadSymbolCodeLengths( s->prev_code_len = prev_code_len; s->repeat_code_len = repeat_code_len; s->space = space; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } BrotliFillBitWindow16(br); p += BrotliGetBitsUnmasked(br) & BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH); BrotliDropBits(br, p->bits); /* Use 1..5 bits */ code_len = p->value; /* code_len == 0..17 */ - if (code_len < kCodeLengthRepeatCode) { + if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) { ProcessSingleCodeLength(code_len, &symbol, &repeat, &space, &prev_code_len, symbol_lists, code_length_histo, next_symbol); } else { /* code_len == 16..17, extra_bits == 2..3 */ + uint32_t extra_bits = + (code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) ? 2 : 3; uint32_t repeat_delta = - (uint32_t)BrotliGetBitsUnmasked(br) & BitMask(code_len - 14U); - BrotliDropBits(br, code_len - 14U); + (uint32_t)BrotliGetBitsUnmasked(br) & BitMask(extra_bits); + BrotliDropBits(br, extra_bits); ProcessRepeatedCodeLength(code_len, repeat_delta, alphabet_size, &symbol, &repeat, &space, &prev_code_len, &repeat_code_len, symbol_lists, code_length_histo, next_symbol); } } s->space = space; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } -static BrotliErrorCode SafeReadSymbolCodeLengths( - uint32_t alphabet_size, BrotliState* s) { +static BrotliDecoderErrorCode SafeReadSymbolCodeLengths( + uint32_t alphabet_size, BrotliDecoderState* s) { BrotliBitReader* br = &s->br; + BROTLI_BOOL get_byte = BROTLI_FALSE; while (s->symbol < alphabet_size && s->space > 0) { const HuffmanCode* p = s->table; uint32_t code_len; + uint32_t available_bits; uint32_t bits = 0; - uint32_t available_bits = BrotliGetAvailableBits(br); + if (get_byte && !BrotliPullByte(br)) return BROTLI_DECODER_NEEDS_MORE_INPUT; + get_byte = BROTLI_FALSE; + available_bits = BrotliGetAvailableBits(br); if (available_bits != 0) { bits = (uint32_t)BrotliGetBitsUnmasked(br); } p += bits & BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH); - if (p->bits > available_bits) goto pullMoreInput; + if (p->bits > available_bits) { + get_byte = BROTLI_TRUE; + continue; + } code_len = p->value; /* code_len == 0..17 */ - if (code_len < kCodeLengthRepeatCode) { + if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) { BrotliDropBits(br, p->bits); ProcessSingleCodeLength(code_len, &s->symbol, &s->repeat, &s->space, &s->prev_code_len, s->symbol_lists, s->code_length_histo, @@ -599,35 +625,32 @@ static BrotliErrorCode SafeReadSymbolCodeLengths( } else { /* code_len == 16..17, extra_bits == 2..3 */ uint32_t extra_bits = code_len - 14U; uint32_t repeat_delta = (bits >> p->bits) & BitMask(extra_bits); - if (available_bits < p->bits + extra_bits) goto pullMoreInput; + if (available_bits < p->bits + extra_bits) { + get_byte = BROTLI_TRUE; + continue; + } BrotliDropBits(br, p->bits + extra_bits); ProcessRepeatedCodeLength(code_len, repeat_delta, alphabet_size, &s->symbol, &s->repeat, &s->space, &s->prev_code_len, &s->repeat_code_len, s->symbol_lists, s->code_length_histo, s->next_symbol); } - continue; - -pullMoreInput: - if (!BrotliPullByte(br)) { - return BROTLI_NEEDS_MORE_INPUT; - } } - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* Reads and decodes 15..18 codes using static prefix code. Each code is 2..4 bits long. In total 30..72 bits are used. */ -static BrotliErrorCode ReadCodeLengthCodeLengths(BrotliState* s) { +static BrotliDecoderErrorCode ReadCodeLengthCodeLengths(BrotliDecoderState* s) { BrotliBitReader* br = &s->br; uint32_t num_codes = s->repeat; unsigned space = s->space; uint32_t i = s->sub_loop_counter; - for (; i < CODE_LENGTH_CODES; ++i) { + for (; i < BROTLI_CODE_LENGTH_CODES; ++i) { const uint8_t code_len_idx = kCodeLengthCodeOrder[i]; uint32_t ix; uint32_t v; - if (PREDICT_FALSE(!BrotliSafeGetBits(br, 4, &ix))) { + if (BROTLI_PREDICT_FALSE(!BrotliSafeGetBits(br, 4, &ix))) { uint32_t available_bits = BrotliGetAvailableBits(br); if (available_bits != 0) { ix = BrotliGetBitsUnmasked(br) & 0xF; @@ -639,7 +662,7 @@ static BrotliErrorCode ReadCodeLengthCodeLengths(BrotliState* s) { s->repeat = num_codes; s->space = space; s->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } } v = kCodeLengthPrefixValue[ix]; @@ -657,9 +680,9 @@ static BrotliErrorCode ReadCodeLengthCodeLengths(BrotliState* s) { } } if (!(num_codes == 1 || space == 0)) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_CL_SPACE); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_CL_SPACE); } - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* Decodes the Huffman tables. @@ -674,119 +697,123 @@ static BrotliErrorCode ReadCodeLengthCodeLengths(BrotliState* s) { B.2) Decoded table is used to decode code lengths of symbols in resulting Huffman table. In worst case 3520 bits are read. */ -static BrotliErrorCode ReadHuffmanCode(uint32_t alphabet_size, - HuffmanCode* table, - uint32_t* opt_table_size, - BrotliState* s) { +static BrotliDecoderErrorCode ReadHuffmanCode(uint32_t alphabet_size, + HuffmanCode* table, + uint32_t* opt_table_size, + BrotliDecoderState* s) { BrotliBitReader* br = &s->br; /* Unnecessary masking, but might be good for safety. */ alphabet_size &= 0x3ff; /* State machine */ - switch (s->substate_huffman) { - case BROTLI_STATE_HUFFMAN_NONE: - if (!BrotliSafeReadBits(br, 2, &s->sub_loop_counter)) { - return BROTLI_NEEDS_MORE_INPUT; - } - BROTLI_LOG_UINT(s->sub_loop_counter); - /* The value is used as follows: - 1 for simple code; - 0 for no skipping, 2 skips 2 code lengths, 3 skips 3 code lengths */ - if (s->sub_loop_counter != 1) { - s->space = 32; - s->repeat = 0; /* num_codes */ - memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo[0]) * - (BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH + 1)); - memset(&s->code_length_code_lengths[0], 0, - sizeof(s->code_length_code_lengths)); - s->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX; - goto Complex; - } - /* No break, transit to the next state. */ + for (;;) { + switch (s->substate_huffman) { + case BROTLI_STATE_HUFFMAN_NONE: + if (!BrotliSafeReadBits(br, 2, &s->sub_loop_counter)) { + return BROTLI_DECODER_NEEDS_MORE_INPUT; + } + BROTLI_LOG_UINT(s->sub_loop_counter); + /* The value is used as follows: + 1 for simple code; + 0 for no skipping, 2 skips 2 code lengths, 3 skips 3 code lengths */ + if (s->sub_loop_counter != 1) { + s->space = 32; + s->repeat = 0; /* num_codes */ + memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo[0]) * + (BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH + 1)); + memset(&s->code_length_code_lengths[0], 0, + sizeof(s->code_length_code_lengths)); + s->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX; + continue; + } + /* No break, transit to the next state. */ - case BROTLI_STATE_HUFFMAN_SIMPLE_SIZE: - /* Read symbols, codes & code lengths directly. */ - if (!BrotliSafeReadBits(br, 2, &s->symbol)) { /* num_symbols */ - s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_SIZE; - return BROTLI_NEEDS_MORE_INPUT; - } - s->sub_loop_counter = 0; - /* No break, transit to the next state. */ - case BROTLI_STATE_HUFFMAN_SIMPLE_READ: { - BrotliErrorCode result = ReadSimpleHuffmanSymbols(alphabet_size, s); - if (result != BROTLI_SUCCESS) { - return result; - } - /* No break, transit to the next state. */ - } - case BROTLI_STATE_HUFFMAN_SIMPLE_BUILD: { - uint32_t table_size; - if (s->symbol == 3) { - uint32_t bits; - if (!BrotliSafeReadBits(br, 1, &bits)) { - s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_BUILD; - return BROTLI_NEEDS_MORE_INPUT; + case BROTLI_STATE_HUFFMAN_SIMPLE_SIZE: + /* Read symbols, codes & code lengths directly. */ + if (!BrotliSafeReadBits(br, 2, &s->symbol)) { /* num_symbols */ + s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_SIZE; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } - s->symbol += bits; + s->sub_loop_counter = 0; + /* No break, transit to the next state. */ + case BROTLI_STATE_HUFFMAN_SIMPLE_READ: { + BrotliDecoderErrorCode result = + ReadSimpleHuffmanSymbols(alphabet_size, s); + if (result != BROTLI_DECODER_SUCCESS) { + return result; + } + /* No break, transit to the next state. */ } - BROTLI_LOG_UINT(s->symbol); - table_size = BrotliBuildSimpleHuffmanTable( - table, HUFFMAN_TABLE_BITS, s->symbols_lists_array, s->symbol); - if (opt_table_size) { - *opt_table_size = table_size; + case BROTLI_STATE_HUFFMAN_SIMPLE_BUILD: { + uint32_t table_size; + if (s->symbol == 3) { + uint32_t bits; + if (!BrotliSafeReadBits(br, 1, &bits)) { + s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_BUILD; + return BROTLI_DECODER_NEEDS_MORE_INPUT; + } + s->symbol += bits; + } + BROTLI_LOG_UINT(s->symbol); + table_size = BrotliBuildSimpleHuffmanTable( + table, HUFFMAN_TABLE_BITS, s->symbols_lists_array, s->symbol); + if (opt_table_size) { + *opt_table_size = table_size; + } + s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; + return BROTLI_DECODER_SUCCESS; } - s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; - return BROTLI_SUCCESS; - } -Complex: /* Decode Huffman-coded code lengths. */ - case BROTLI_STATE_HUFFMAN_COMPLEX: { - uint32_t i; - BrotliErrorCode result = ReadCodeLengthCodeLengths(s); - if (result != BROTLI_SUCCESS) { - return result; - } - BrotliBuildCodeLengthsHuffmanTable(s->table, - s->code_length_code_lengths, - s->code_length_histo); - memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo)); - for (i = 0; i <= BROTLI_HUFFMAN_MAX_CODE_LENGTH; ++i) { - s->next_symbol[i] = (int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1); - s->symbol_lists[(int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1)] = 0xFFFF; - } + /* Decode Huffman-coded code lengths. */ + case BROTLI_STATE_HUFFMAN_COMPLEX: { + uint32_t i; + BrotliDecoderErrorCode result = ReadCodeLengthCodeLengths(s); + if (result != BROTLI_DECODER_SUCCESS) { + return result; + } + BrotliBuildCodeLengthsHuffmanTable(s->table, + s->code_length_code_lengths, + s->code_length_histo); + memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo)); + for (i = 0; i <= BROTLI_HUFFMAN_MAX_CODE_LENGTH; ++i) { + s->next_symbol[i] = (int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1); + s->symbol_lists[s->next_symbol[i]] = 0xFFFF; + } - s->symbol = 0; - s->prev_code_len = kDefaultCodeLength; - s->repeat = 0; - s->repeat_code_len = 0; - s->space = 32768; - s->substate_huffman = BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS; - /* No break, transit to the next state. */ - } - case BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS: { - uint32_t table_size; - BrotliErrorCode result = ReadSymbolCodeLengths(alphabet_size, s); - if (result == BROTLI_NEEDS_MORE_INPUT) { - result = SafeReadSymbolCodeLengths(alphabet_size, s); - } - if (result != BROTLI_SUCCESS) { - return result; + s->symbol = 0; + s->prev_code_len = BROTLI_INITIAL_REPEATED_CODE_LENGTH; + s->repeat = 0; + s->repeat_code_len = 0; + s->space = 32768; + s->substate_huffman = BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS; + /* No break, transit to the next state. */ } + case BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS: { + uint32_t table_size; + BrotliDecoderErrorCode result = ReadSymbolCodeLengths(alphabet_size, s); + if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { + result = SafeReadSymbolCodeLengths(alphabet_size, s); + } + if (result != BROTLI_DECODER_SUCCESS) { + return result; + } - if (s->space != 0) { - BROTLI_LOG(("[ReadHuffmanCode] space = %d\n", s->space)); - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_HUFFMAN_SPACE); - } - table_size = BrotliBuildHuffmanTable( - table, HUFFMAN_TABLE_BITS, s->symbol_lists, s->code_length_histo); - if (opt_table_size) { - *opt_table_size = table_size; + if (s->space != 0) { + BROTLI_LOG(("[ReadHuffmanCode] space = %d\n", s->space)); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_HUFFMAN_SPACE); + } + table_size = BrotliBuildHuffmanTable( + table, HUFFMAN_TABLE_BITS, s->symbol_lists, s->code_length_histo); + if (opt_table_size) { + *opt_table_size = table_size; + } + s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; + return BROTLI_DECODER_SUCCESS; } - s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; - return BROTLI_SUCCESS; - } - default: - return BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE); + default: + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE); + } } } @@ -802,14 +829,13 @@ static BROTLI_INLINE uint32_t ReadBlockLength(const HuffmanCode* table, /* WARNING: if state is not BROTLI_STATE_READ_BLOCK_LENGTH_NONE, then reading can't be continued with ReadBlockLength. */ -static BROTLI_INLINE int SafeReadBlockLength(BrotliState* s, - uint32_t* result, - const HuffmanCode* table, - BrotliBitReader* br) { +static BROTLI_INLINE BROTLI_BOOL SafeReadBlockLength( + BrotliDecoderState* s, uint32_t* result, const HuffmanCode* table, + BrotliBitReader* br) { uint32_t index; if (s->substate_read_block_length == BROTLI_STATE_READ_BLOCK_LENGTH_NONE) { if (!SafeReadSymbol(table, br, &index)) { - return 0; + return BROTLI_FALSE; } } else { index = s->block_length_index; @@ -820,11 +846,11 @@ static BROTLI_INLINE int SafeReadBlockLength(BrotliState* s, if (!BrotliSafeReadBits(br, nbits, &bits)) { s->block_length_index = index; s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_SUFFIX; - return 0; + return BROTLI_FALSE; } *result = kBlockLengthPrefixCode[index].offset + bits; s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; - return 1; + return BROTLI_TRUE; } } @@ -843,45 +869,46 @@ static BROTLI_INLINE int SafeReadBlockLength(BrotliState* s, Most of input values are 0 and 1. To reduce number of branches, we replace inner for loop with do-while. */ -static BROTLI_NOINLINE void InverseMoveToFrontTransform(uint8_t* v, - uint32_t v_len, BrotliState* state) { +static BROTLI_NOINLINE void InverseMoveToFrontTransform( + uint8_t* v, uint32_t v_len, BrotliDecoderState* state) { /* Reinitialize elements that could have been changed. */ - uint32_t i = 4; + uint32_t i = 1; uint32_t upper_bound = state->mtf_upper_bound; - uint8_t* mtf = &state->mtf[4]; /* Make mtf[-1] addressable. */ + uint32_t* mtf = &state->mtf[1]; /* Make mtf[-1] addressable. */ + uint8_t* mtf_u8 = (uint8_t*)mtf; /* Load endian-aware constant. */ const uint8_t b0123[4] = {0, 1, 2, 3}; uint32_t pattern; memcpy(&pattern, &b0123, 4); /* Initialize list using 4 consequent values pattern. */ - *(uint32_t*)mtf = pattern; + mtf[0] = pattern; do { pattern += 0x04040404; /* Advance all 4 values by 4. */ - *(uint32_t*)(mtf + i) = pattern; - i += 4; + mtf[i] = pattern; + i++; } while (i <= upper_bound); /* Transform the input. */ upper_bound = 0; for (i = 0; i < v_len; ++i) { int index = v[i]; - uint8_t value = mtf[index]; + uint8_t value = mtf_u8[index]; upper_bound |= v[i]; v[i] = value; - mtf[-1] = value; + mtf_u8[-1] = value; do { index--; - mtf[index + 1] = mtf[index]; + mtf_u8[index + 1] = mtf_u8[index]; } while (index >= 0); } /* Remember amount of elements to be reinitialized. */ - state->mtf_upper_bound = upper_bound; + state->mtf_upper_bound = upper_bound >> 2; } /* Decodes a series of Huffman table using ReadHuffmanCode function. */ -static BrotliErrorCode HuffmanTreeGroupDecode(HuffmanTreeGroup* group, - BrotliState* s) { +static BrotliDecoderErrorCode HuffmanTreeGroupDecode( + HuffmanTreeGroup* group, BrotliDecoderState* s) { if (s->substate_tree_group != BROTLI_STATE_TREE_GROUP_LOOP) { s->next = group->codes; s->htree_index = 0; @@ -889,15 +916,15 @@ static BrotliErrorCode HuffmanTreeGroupDecode(HuffmanTreeGroup* group, } while (s->htree_index < group->num_htrees) { uint32_t table_size; - BrotliErrorCode result = + BrotliDecoderErrorCode result = ReadHuffmanCode(group->alphabet_size, s->next, &table_size, s); - if (result != BROTLI_SUCCESS) return result; + if (result != BROTLI_DECODER_SUCCESS) return result; group->htrees[s->htree_index] = s->next; s->next += table_size; ++s->htree_index; } s->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } /* Decodes a context map. @@ -909,17 +936,17 @@ static BrotliErrorCode HuffmanTreeGroupDecode(HuffmanTreeGroup* group, 3) Read context map items; "0" values could be run-length encoded. 4) Optionally, apply InverseMoveToFront transform to the resulting map. */ -static BrotliErrorCode DecodeContextMap(uint32_t context_map_size, - uint32_t* num_htrees, - uint8_t** context_map_arg, - BrotliState* s) { +static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size, + uint32_t* num_htrees, + uint8_t** context_map_arg, + BrotliDecoderState* s) { BrotliBitReader* br = &s->br; - BrotliErrorCode result = BROTLI_SUCCESS; + BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; switch ((int)s->substate_context_map) { case BROTLI_STATE_CONTEXT_MAP_NONE: result = DecodeVarLenUint8(s, br, num_htrees); - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { return result; } (*num_htrees)++; @@ -928,11 +955,11 @@ static BrotliErrorCode DecodeContextMap(uint32_t context_map_size, BROTLI_LOG_UINT(*num_htrees); *context_map_arg = (uint8_t*)BROTLI_ALLOC(s, (size_t)context_map_size); if (*context_map_arg == 0) { - return BROTLI_FAILURE(BROTLI_ERROR_ALLOC_CONTEXT_MAP); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MAP); } if (*num_htrees <= 1) { memset(*context_map_arg, 0, (size_t)context_map_size); - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_READ_PREFIX; /* No break, continue to next state. */ @@ -941,9 +968,9 @@ static BrotliErrorCode DecodeContextMap(uint32_t context_map_size, /* In next stage ReadHuffmanCode uses at least 4 bits, so it is safe to peek 4 bits ahead. */ if (!BrotliSafeGetBits(br, 5, &bits)) { - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } - if ((bits & 1) != 0) { /* Use RLE for zeroes. */ + if ((bits & 1) != 0) { /* Use RLE for zeros. */ s->max_run_length_prefix = (bits >> 1) + 1; BrotliDropBits(br, 5); } else { @@ -957,7 +984,7 @@ static BrotliErrorCode DecodeContextMap(uint32_t context_map_size, case BROTLI_STATE_CONTEXT_MAP_HUFFMAN: result = ReadHuffmanCode(*num_htrees + s->max_run_length_prefix, s->context_map_table, NULL, s); - if (result != BROTLI_SUCCESS) return result; + if (result != BROTLI_DECODER_SUCCESS) return result; s->code = 0xFFFF; s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_DECODE; /* No break, continue to next state. */ @@ -966,38 +993,41 @@ static BrotliErrorCode DecodeContextMap(uint32_t context_map_size, uint32_t max_run_length_prefix = s->max_run_length_prefix; uint8_t* context_map = *context_map_arg; uint32_t code = s->code; - if (code != 0xFFFF) { - goto rleCode; - } - while (context_index < context_map_size) { - if (!SafeReadSymbol(s->context_map_table, br, &code)) { - s->code = 0xFFFF; - s->context_index = context_index; - return BROTLI_NEEDS_MORE_INPUT; - } - BROTLI_LOG_UINT(code); + BROTLI_BOOL skip_preamble = (code != 0xFFFF); + while (context_index < context_map_size || skip_preamble) { + if (!skip_preamble) { + if (!SafeReadSymbol(s->context_map_table, br, &code)) { + s->code = 0xFFFF; + s->context_index = context_index; + return BROTLI_DECODER_NEEDS_MORE_INPUT; + } + BROTLI_LOG_UINT(code); - if (code == 0) { - context_map[context_index++] = 0; - continue; - } - if (code > max_run_length_prefix) { - context_map[context_index++] = - (uint8_t)(code - max_run_length_prefix); - continue; + if (code == 0) { + context_map[context_index++] = 0; + continue; + } + if (code > max_run_length_prefix) { + context_map[context_index++] = + (uint8_t)(code - max_run_length_prefix); + continue; + } + } else { + skip_preamble = BROTLI_FALSE; } -rleCode: + /* RLE sub-stage. */ { uint32_t reps; if (!BrotliSafeReadBits(br, code, &reps)) { s->code = code; s->context_index = context_index; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } reps += 1U << code; BROTLI_LOG_UINT(reps); if (context_index + reps > context_map_size) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_CONTEXT_MAP_REPEAT); + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_CONTEXT_MAP_REPEAT); } do { context_map[context_index++] = 0; @@ -1010,23 +1040,24 @@ rleCode: uint32_t bits; if (!BrotliSafeReadBits(br, 1, &bits)) { s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_TRANSFORM; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } if (bits != 0) { InverseMoveToFrontTransform(*context_map_arg, context_map_size, s); } s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE; - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } default: - return BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE); + return + BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE); } } -/* Decodes a command or literal and updates block type ringbuffer. +/* Decodes a command or literal and updates block type ring-buffer. Reads 3..54 bits. */ -static BROTLI_INLINE int DecodeBlockTypeAndLength(int safe, - BrotliState* s, int tree_type) { +static BROTLI_INLINE BROTLI_BOOL DecodeBlockTypeAndLength( + int safe, BrotliDecoderState* s, int tree_type) { uint32_t max_block_type = s->num_block_types[tree_type]; const HuffmanCode* type_tree = &s->block_type_trees[ tree_type * BROTLI_HUFFMAN_MAX_SIZE_258]; @@ -1043,11 +1074,11 @@ static BROTLI_INLINE int DecodeBlockTypeAndLength(int safe, } else { BrotliBitReaderState memento; BrotliBitReaderSaveState(br, &memento); - if (!SafeReadSymbol(type_tree, br, &block_type)) return 0; + if (!SafeReadSymbol(type_tree, br, &block_type)) return BROTLI_FALSE; if (!SafeReadBlockLength(s, &s->block_length[tree_type], len_tree, br)) { s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; BrotliBitReaderRestoreState(br, &memento); - return 0; + return BROTLI_FALSE; } } @@ -1063,18 +1094,19 @@ static BROTLI_INLINE int DecodeBlockTypeAndLength(int safe, } ringbuffer[0] = ringbuffer[1]; ringbuffer[1] = block_type; - return 1; + return BROTLI_TRUE; } -static BROTLI_INLINE void DetectTrivialLiteralBlockTypes(BrotliState* s) { +static BROTLI_INLINE void DetectTrivialLiteralBlockTypes( + BrotliDecoderState* s) { size_t i; for (i = 0; i < 8; ++i) s->trivial_literal_contexts[i] = 0; for (i = 0; i < s->num_block_types[0]; i++) { - size_t offset = i << kLiteralContextBits; + size_t offset = i << BROTLI_LITERAL_CONTEXT_BITS; size_t error = 0; size_t sample = s->context_map[offset]; size_t j; - for (j = 0; j < (1u << kLiteralContextBits);) { + for (j = 0; j < (1u << BROTLI_LITERAL_CONTEXT_BITS);) { BROTLI_REPEAT(4, error |= s->context_map[offset + j++] ^ sample;) } if (error == 0) { @@ -1083,11 +1115,11 @@ static BROTLI_INLINE void DetectTrivialLiteralBlockTypes(BrotliState* s) { } } -static BROTLI_INLINE void PrepareLiteralDecoding(BrotliState* s) { +static BROTLI_INLINE void PrepareLiteralDecoding(BrotliDecoderState* s) { uint8_t context_mode; size_t trivial; uint32_t block_type = s->block_type_rb[1]; - uint32_t context_offset = block_type << kLiteralContextBits; + uint32_t context_offset = block_type << BROTLI_LITERAL_CONTEXT_BITS; s->context_map_slice = s->context_map + context_offset; trivial = s->trivial_literal_contexts[block_type >> 5]; s->trivial_literal_context = (trivial >> (block_type & 31)) & 1; @@ -1099,135 +1131,171 @@ static BROTLI_INLINE void PrepareLiteralDecoding(BrotliState* s) { /* Decodes the block type and updates the state for literal context. Reads 3..54 bits. */ -static BROTLI_INLINE int DecodeLiteralBlockSwitchInternal(int safe, - BrotliState* s) { +static BROTLI_INLINE BROTLI_BOOL DecodeLiteralBlockSwitchInternal( + int safe, BrotliDecoderState* s) { if (!DecodeBlockTypeAndLength(safe, s, 0)) { - return 0; + return BROTLI_FALSE; } PrepareLiteralDecoding(s); - return 1; + return BROTLI_TRUE; } -static void BROTLI_NOINLINE DecodeLiteralBlockSwitch(BrotliState* s) { +static void BROTLI_NOINLINE DecodeLiteralBlockSwitch(BrotliDecoderState* s) { DecodeLiteralBlockSwitchInternal(0, s); } -static int BROTLI_NOINLINE SafeDecodeLiteralBlockSwitch(BrotliState* s) { +static BROTLI_BOOL BROTLI_NOINLINE SafeDecodeLiteralBlockSwitch( + BrotliDecoderState* s) { return DecodeLiteralBlockSwitchInternal(1, s); } /* Block switch for insert/copy length. Reads 3..54 bits. */ -static BROTLI_INLINE int DecodeCommandBlockSwitchInternal(int safe, - BrotliState* s) { +static BROTLI_INLINE BROTLI_BOOL DecodeCommandBlockSwitchInternal( + int safe, BrotliDecoderState* s) { if (!DecodeBlockTypeAndLength(safe, s, 1)) { - return 0; + return BROTLI_FALSE; } s->htree_command = s->insert_copy_hgroup.htrees[s->block_type_rb[3]]; - return 1; + return BROTLI_TRUE; } -static void BROTLI_NOINLINE DecodeCommandBlockSwitch(BrotliState* s) { +static void BROTLI_NOINLINE DecodeCommandBlockSwitch(BrotliDecoderState* s) { DecodeCommandBlockSwitchInternal(0, s); } -static int BROTLI_NOINLINE SafeDecodeCommandBlockSwitch(BrotliState* s) { +static BROTLI_BOOL BROTLI_NOINLINE SafeDecodeCommandBlockSwitch( + BrotliDecoderState* s) { return DecodeCommandBlockSwitchInternal(1, s); } /* Block switch for distance codes. Reads 3..54 bits. */ -static BROTLI_INLINE int DecodeDistanceBlockSwitchInternal(int safe, - BrotliState* s) { +static BROTLI_INLINE BROTLI_BOOL DecodeDistanceBlockSwitchInternal( + int safe, BrotliDecoderState* s) { if (!DecodeBlockTypeAndLength(safe, s, 2)) { - return 0; + return BROTLI_FALSE; } - s->dist_context_map_slice = - s->dist_context_map + (s->block_type_rb[5] << kDistanceContextBits); + s->dist_context_map_slice = s->dist_context_map + + (s->block_type_rb[5] << BROTLI_DISTANCE_CONTEXT_BITS); s->dist_htree_index = s->dist_context_map_slice[s->distance_context]; - return 1; + return BROTLI_TRUE; } -static void BROTLI_NOINLINE DecodeDistanceBlockSwitch(BrotliState* s) { +static void BROTLI_NOINLINE DecodeDistanceBlockSwitch(BrotliDecoderState* s) { DecodeDistanceBlockSwitchInternal(0, s); } -static int BROTLI_NOINLINE SafeDecodeDistanceBlockSwitch(BrotliState* s) { +static BROTLI_BOOL BROTLI_NOINLINE SafeDecodeDistanceBlockSwitch( + BrotliDecoderState* s) { return DecodeDistanceBlockSwitchInternal(1, s); } -static BrotliErrorCode BROTLI_NOINLINE WriteRingBuffer(size_t* available_out, - uint8_t** next_out, size_t* total_out, BrotliState* s) { - size_t pos = (s->pos > s->ringbuffer_size) ? (size_t)s->ringbuffer_size - : (size_t)(s->pos); +static size_t UnwrittenBytes(const BrotliDecoderState* s, BROTLI_BOOL wrap) { + size_t pos = wrap && s->pos > s->ringbuffer_size ? + (size_t)s->ringbuffer_size : (size_t)(s->pos); + size_t partial_pos_rb = (s->rb_roundtrips * (size_t)s->ringbuffer_size) + pos; + return partial_pos_rb - s->partial_pos_out; +} + +/* Dumps output. + Returns BROTLI_DECODER_NEEDS_MORE_OUTPUT only if there is more output to push + and either ring-buffer is as big as window size, or |force| is true. + */ +static BrotliDecoderErrorCode BROTLI_NOINLINE WriteRingBuffer( + BrotliDecoderState* s, size_t* available_out, uint8_t** next_out, + size_t* total_out, BROTLI_BOOL force) { uint8_t* start = s->ringbuffer + (s->partial_pos_out & (size_t)s->ringbuffer_mask); - size_t partial_pos_rb = (s->rb_roundtrips * (size_t)s->ringbuffer_size) + pos; - size_t to_write = (partial_pos_rb - s->partial_pos_out); + size_t to_write = UnwrittenBytes(s, BROTLI_TRUE); size_t num_written = *available_out; if (num_written > to_write) { num_written = to_write; } if (s->meta_block_remaining_len < 0) { - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_BLOCK_LENGTH_1); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_1); + } + if (next_out && !*next_out) { + *next_out = start; + } else { + if (next_out) { + memcpy(*next_out, start, num_written); + *next_out += num_written; + } } - memcpy(*next_out, start, num_written); - *next_out += num_written; *available_out -= num_written; BROTLI_LOG_UINT(to_write); BROTLI_LOG_UINT(num_written); s->partial_pos_out += num_written; - if (total_out) *total_out = s->partial_pos_out; + if (total_out) { + *total_out = s->partial_pos_out; + } if (num_written < to_write) { - return BROTLI_NEEDS_MORE_OUTPUT; + if (s->ringbuffer_size == (1 << s->window_bits) || force) { + return BROTLI_DECODER_NEEDS_MORE_OUTPUT; + } else { + return BROTLI_DECODER_SUCCESS; + } } - - if (s->pos >= s->ringbuffer_size) { + /* Wrap ring buffer only if it has reached its maximal size. */ + if (s->ringbuffer_size == (1 << s->window_bits) && + s->pos >= s->ringbuffer_size) { s->pos -= s->ringbuffer_size; s->rb_roundtrips++; + s->should_wrap_ringbuffer = (size_t)s->pos != 0 ? 1 : 0; } - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } -/* Allocates ringbuffer. +static void BROTLI_NOINLINE WrapRingBuffer(BrotliDecoderState* s) { + if (s->should_wrap_ringbuffer) { + memcpy(s->ringbuffer, s->ringbuffer_end, (size_t)s->pos); + s->should_wrap_ringbuffer = 0; + } +} - s->ringbuffer_size MUST be updated by BrotliCalculateRingBufferSize before - this function is called. +/* Allocates ring-buffer. - Last two bytes of ringbuffer are initialized to 0, so context calculation - could be done uniformly for the first two and all other positions. + s->ringbuffer_size MUST be updated by BrotliCalculateRingBufferSize before + this function is called. - Custom dictionary, if any, is copied to the end of ringbuffer. + Last two bytes of ring-buffer are initialized to 0, so context calculation + could be done uniformly for the first two and all other positions. */ -static int BROTLI_NOINLINE BrotliAllocateRingBuffer(BrotliState* s) { - /* We need the slack region for the following reasons: - - doing up to two 16-byte copies for fast backward copying - - inserting transformed dictionary word (5 prefix + 24 base + 8 suffix) */ - static const int kRingBufferWriteAheadSlack = 42; - s->ringbuffer = (uint8_t*)BROTLI_ALLOC(s, (size_t)(s->ringbuffer_size + - kRingBufferWriteAheadSlack)); - if (s->ringbuffer == 0) { - return 0; +static BROTLI_BOOL BROTLI_NOINLINE BrotliEnsureRingBuffer( + BrotliDecoderState* s) { + uint8_t* old_ringbuffer = s->ringbuffer; + if (s->ringbuffer_size == s->new_ringbuffer_size) { + return BROTLI_TRUE; } - s->ringbuffer_end = s->ringbuffer + s->ringbuffer_size; - - s->ringbuffer[s->ringbuffer_size - 2] = 0; - s->ringbuffer[s->ringbuffer_size - 1] = 0; + s->ringbuffer = (uint8_t*)BROTLI_ALLOC(s, (size_t)(s->new_ringbuffer_size) + + kRingBufferWriteAheadSlack); + if (s->ringbuffer == 0) { + /* Restore previous value. */ + s->ringbuffer = old_ringbuffer; + return BROTLI_FALSE; + } + s->ringbuffer[s->new_ringbuffer_size - 2] = 0; + s->ringbuffer[s->new_ringbuffer_size - 1] = 0; - if (s->custom_dict) { - memcpy(&s->ringbuffer[(-s->custom_dict_size) & s->ringbuffer_mask], - s->custom_dict, (size_t)s->custom_dict_size); + if (!!old_ringbuffer) { + memcpy(s->ringbuffer, old_ringbuffer, (size_t)s->pos); + BROTLI_FREE(s, old_ringbuffer); } - return 1; + s->ringbuffer_size = s->new_ringbuffer_size; + s->ringbuffer_mask = s->new_ringbuffer_size - 1; + s->ringbuffer_end = s->ringbuffer + s->ringbuffer_size; + + return BROTLI_TRUE; } -static BrotliErrorCode BROTLI_NOINLINE CopyUncompressedBlockToOutput( +static BrotliDecoderErrorCode BROTLI_NOINLINE CopyUncompressedBlockToOutput( size_t* available_out, uint8_t** next_out, size_t* total_out, - BrotliState* s) { + BrotliDecoderState* s) { /* TODO: avoid allocation for single uncompressed block. */ - if (!s->ringbuffer && !BrotliAllocateRingBuffer(s)) { - return BROTLI_FAILURE(BROTLI_ERROR_ALLOC_RING_BUFFER_1); + if (!BrotliEnsureRingBuffer(s)) { + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_1); } /* State machine */ @@ -1241,26 +1309,29 @@ static BrotliErrorCode BROTLI_NOINLINE CopyUncompressedBlockToOutput( if (s->pos + nbytes > s->ringbuffer_size) { nbytes = s->ringbuffer_size - s->pos; } - /* Copy remaining bytes from s->br.buf_ to ringbuffer. */ + /* Copy remaining bytes from s->br.buf_ to ring-buffer. */ BrotliCopyBytes(&s->ringbuffer[s->pos], &s->br, (size_t)nbytes); s->pos += nbytes; s->meta_block_remaining_len -= nbytes; - if (s->pos < s->ringbuffer_size) { + if (s->pos < 1 << s->window_bits) { if (s->meta_block_remaining_len == 0) { - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_WRITE; /* No break, continue to next state */ } case BROTLI_STATE_UNCOMPRESSED_WRITE: { - BrotliErrorCode result = - WriteRingBuffer(available_out, next_out, total_out, s); - if (result != BROTLI_SUCCESS) { + BrotliDecoderErrorCode result; + result = WriteRingBuffer( + s, available_out, next_out, total_out, BROTLI_FALSE); + if (result != BROTLI_DECODER_SUCCESS) { return result; } - s->max_distance = s->max_backward_distance; + if (s->ringbuffer_size == 1 << s->window_bits) { + s->max_distance = s->max_backward_distance; + } s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE; break; } @@ -1269,69 +1340,54 @@ static BrotliErrorCode BROTLI_NOINLINE CopyUncompressedBlockToOutput( BROTLI_DCHECK(0); /* Unreachable */ } -int BrotliDecompressedSize(size_t encoded_size, - const uint8_t* encoded_buffer, - size_t* decoded_size) { - BrotliState s; - int next_block_header; - BrotliStateInit(&s); - s.br.next_in = encoded_buffer; - s.br.avail_in = encoded_size; - if (!BrotliWarmupBitReader(&s.br)) { - return 0; - } - DecodeWindowBits(&s.br); - if (DecodeMetaBlockLength(&s, &s.br) != BROTLI_SUCCESS) { - return 0; - } - *decoded_size = (size_t)s.meta_block_remaining_len; - if (s.is_last_metablock) { - return 1; - } - if (!s.is_uncompressed || !BrotliJumpToByteBoundary(&s.br)) { - return 0; - } - next_block_header = BrotliPeekByte(&s.br, (size_t)s.meta_block_remaining_len); - return (next_block_header != -1) && ((next_block_header & 3) == 3); -} - /* Calculates the smallest feasible ring buffer. - If we know the data size is small, do not allocate more ringbuffer + If we know the data size is small, do not allocate more ring buffer size than needed to reduce memory usage. When this method is called, metablock size and flags MUST be decoded. */ -static void BROTLI_NOINLINE BrotliCalculateRingBufferSize(BrotliState* s, - BrotliBitReader* br) { - int is_last = s->is_last_metablock; +static void BROTLI_NOINLINE BrotliCalculateRingBufferSize( + BrotliDecoderState* s) { int window_size = 1 << s->window_bits; - s->ringbuffer_size = window_size; - - if (s->is_uncompressed) { - int next_block_header = - BrotliPeekByte(br, (size_t)s->meta_block_remaining_len); - if (next_block_header != -1) { /* Peek succeeded */ - if ((next_block_header & 3) == 3) { /* ISLAST and ISEMPTY */ - is_last = 1; - } - } - } - + int new_ringbuffer_size = window_size; /* We need at least 2 bytes of ring buffer size to get the last two bytes for context from there */ - if (is_last) { - int min_size_x2 = (s->meta_block_remaining_len + s->custom_dict_size) * 2; - while (s->ringbuffer_size >= min_size_x2 && s->ringbuffer_size > 32) { - s->ringbuffer_size >>= 1; + int min_size = s->ringbuffer_size ? s->ringbuffer_size : 1024; + int output_size; + + /* If maximum is already reached, no further extension is retired. */ + if (s->ringbuffer_size == window_size) { + return; + } + + /* Metadata blocks does not touch ring buffer. */ + if (s->is_metadata) { + return; + } + + if (!s->ringbuffer) { + output_size = 0; + } else { + output_size = s->pos; + } + output_size += s->meta_block_remaining_len; + min_size = min_size < output_size ? output_size : min_size; + + if (!!s->canny_ringbuffer_allocation) { + /* Reduce ring buffer size to save memory when server is unscrupulous. + In worst case memory usage might be 1.5x bigger for a short period of + ring buffer reallocation.*/ + while ((new_ringbuffer_size >> 1) >= min_size) { + new_ringbuffer_size >>= 1; } } - s->ringbuffer_mask = s->ringbuffer_size - 1; + s->new_ringbuffer_size = new_ringbuffer_size; } /* Reads 1..256 2-bit context modes. */ -static BrotliErrorCode ReadContextModes(BrotliState* s) { +static BrotliDecoderErrorCode ReadContextModes(BrotliDecoderState* s) { BrotliBitReader* br = &s->br; int i = s->loop_counter; @@ -1339,19 +1395,21 @@ static BrotliErrorCode ReadContextModes(BrotliState* s) { uint32_t bits; if (!BrotliSafeReadBits(br, 2, &bits)) { s->loop_counter = i; - return BROTLI_NEEDS_MORE_INPUT; + return BROTLI_DECODER_NEEDS_MORE_INPUT; } s->context_modes[i] = (uint8_t)(bits << 1); BROTLI_LOG_ARRAY_INDEX(s->context_modes, i); i++; } - return BROTLI_SUCCESS; + return BROTLI_DECODER_SUCCESS; } -static BROTLI_INLINE void TakeDistanceFromRingBuffer(BrotliState* s) { +static BROTLI_INLINE void TakeDistanceFromRingBuffer(BrotliDecoderState* s) { if (s->distance_code == 0) { --s->dist_rb_idx; s->distance_code = s->dist_rb[s->dist_rb_idx & 3]; + /* Compensate double distance-ring-buffer roll for dictionary items. */ + s->distance_context = 1; } else { int distance_code = s->distance_code << 1; /* kDistanceShortCodeIndexOffset has 2-bit values from LSB: */ @@ -1377,19 +1435,19 @@ static BROTLI_INLINE void TakeDistanceFromRingBuffer(BrotliState* s) { } } -static BROTLI_INLINE int SafeReadBits( +static BROTLI_INLINE BROTLI_BOOL SafeReadBits( BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) { if (n_bits != 0) { return BrotliSafeReadBits(br, n_bits, val); } else { *val = 0; - return 1; + return BROTLI_TRUE; } } /* Precondition: s->distance_code < 0 */ -static BROTLI_INLINE int ReadDistanceInternal(int safe, - BrotliState* s, BrotliBitReader* br) { +static BROTLI_INLINE BROTLI_BOOL ReadDistanceInternal( + int safe, BrotliDecoderState* s, BrotliBitReader* br) { int distval; BrotliBitReaderState memento; HuffmanCode* distance_tree = s->distance_hgroup.htrees[s->dist_htree_index]; @@ -1399,16 +1457,17 @@ static BROTLI_INLINE int ReadDistanceInternal(int safe, uint32_t code; BrotliBitReaderSaveState(br, &memento); if (!SafeReadSymbol(distance_tree, br, &code)) { - return 0; + return BROTLI_FALSE; } s->distance_code = (int)code; } /* Convert the distance code to the actual distance by possibly */ /* looking up past distances from the s->ringbuffer. */ + s->distance_context = 0; if ((s->distance_code & ~0xf) == 0) { TakeDistanceFromRingBuffer(s); --s->block_length[2]; - return 1; + return BROTLI_TRUE; } distval = s->distance_code - (int)s->num_direct_distance_codes; if (distval >= 0) { @@ -1430,7 +1489,7 @@ static BROTLI_INLINE int ReadDistanceInternal(int safe, if (!SafeReadBits(br, nbits, &bits)) { s->distance_code = -1; /* Restore precondition. */ BrotliBitReaderRestoreState(br, &memento); - return 0; + return BROTLI_FALSE; } } else { bits = BrotliReadBits(br, nbits); @@ -1440,21 +1499,23 @@ static BROTLI_INLINE int ReadDistanceInternal(int safe, ((offset + (int)bits) << s->distance_postfix_bits) + postfix; } } - s->distance_code = s->distance_code - NUM_DISTANCE_SHORT_CODES + 1; + s->distance_code = s->distance_code - BROTLI_NUM_DISTANCE_SHORT_CODES + 1; --s->block_length[2]; - return 1; + return BROTLI_TRUE; } -static BROTLI_INLINE void ReadDistance(BrotliState* s, BrotliBitReader* br) { +static BROTLI_INLINE void ReadDistance( + BrotliDecoderState* s, BrotliBitReader* br) { ReadDistanceInternal(0, s, br); } -static BROTLI_INLINE int SafeReadDistance(BrotliState* s, BrotliBitReader* br) { +static BROTLI_INLINE BROTLI_BOOL SafeReadDistance( + BrotliDecoderState* s, BrotliBitReader* br) { return ReadDistanceInternal(1, s, br); } -static BROTLI_INLINE int ReadCommandInternal(int safe, - BrotliState* s, BrotliBitReader* br, int* insert_length) { +static BROTLI_INLINE BROTLI_BOOL ReadCommandInternal( + int safe, BrotliDecoderState* s, BrotliBitReader* br, int* insert_length) { uint32_t cmd_code; uint32_t insert_len_extra = 0; uint32_t copy_length; @@ -1465,7 +1526,7 @@ static BROTLI_INLINE int ReadCommandInternal(int safe, } else { BrotliBitReaderSaveState(br, &memento); if (!SafeReadSymbol(s->htree_command, br, &cmd_code)) { - return 0; + return BROTLI_FALSE; } } v = kCmdLut[cmd_code]; @@ -1474,7 +1535,7 @@ static BROTLI_INLINE int ReadCommandInternal(int safe, s->dist_htree_index = s->dist_context_map_slice[s->distance_context]; *insert_length = v.insert_len_offset; if (!safe) { - if (PREDICT_FALSE(v.insert_len_extra_bits != 0)) { + if (BROTLI_PREDICT_FALSE(v.insert_len_extra_bits != 0)) { insert_len_extra = BrotliReadBits(br, v.insert_len_extra_bits); } copy_length = BrotliReadBits(br, v.copy_len_extra_bits); @@ -1482,54 +1543,54 @@ static BROTLI_INLINE int ReadCommandInternal(int safe, if (!SafeReadBits(br, v.insert_len_extra_bits, &insert_len_extra) || !SafeReadBits(br, v.copy_len_extra_bits, ©_length)) { BrotliBitReaderRestoreState(br, &memento); - return 0; + return BROTLI_FALSE; } } s->copy_length = (int)copy_length + v.copy_len_offset; --s->block_length[1]; *insert_length += (int)insert_len_extra; - return 1; + return BROTLI_TRUE; } -static BROTLI_INLINE void ReadCommand(BrotliState* s, BrotliBitReader* br, - int* insert_length) { +static BROTLI_INLINE void ReadCommand( + BrotliDecoderState* s, BrotliBitReader* br, int* insert_length) { ReadCommandInternal(0, s, br, insert_length); } -static BROTLI_INLINE int SafeReadCommand(BrotliState* s, BrotliBitReader* br, - int* insert_length) { +static BROTLI_INLINE BROTLI_BOOL SafeReadCommand( + BrotliDecoderState* s, BrotliBitReader* br, int* insert_length) { return ReadCommandInternal(1, s, br, insert_length); } -static BROTLI_INLINE int CheckInputAmount(int safe, - BrotliBitReader* const br, size_t num) { +static BROTLI_INLINE BROTLI_BOOL CheckInputAmount( + int safe, BrotliBitReader* const br, size_t num) { if (safe) { - return 1; + return BROTLI_TRUE; } return BrotliCheckInputAmount(br, num); } -#define BROTLI_SAFE(METHOD) \ - { \ - if (safe) { \ - if (!Safe##METHOD) { \ - result = BROTLI_NEEDS_MORE_INPUT; \ - goto saveStateAndReturn; \ - } \ - } else { \ - METHOD; \ - } \ +#define BROTLI_SAFE(METHOD) \ + { \ + if (safe) { \ + if (!Safe##METHOD) { \ + result = BROTLI_DECODER_NEEDS_MORE_INPUT; \ + goto saveStateAndReturn; \ + } \ + } else { \ + METHOD; \ + } \ } -static BROTLI_INLINE BrotliErrorCode ProcessCommandsInternal(int safe, - BrotliState* s) { +static BROTLI_INLINE BrotliDecoderErrorCode ProcessCommandsInternal( + int safe, BrotliDecoderState* s) { int pos = s->pos; int i = s->loop_counter; - BrotliErrorCode result = BROTLI_SUCCESS; + BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; BrotliBitReader* br = &s->br; if (!CheckInputAmount(safe, br, 28)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } if (!safe) { @@ -1546,7 +1607,7 @@ static BROTLI_INLINE BrotliErrorCode ProcessCommandsInternal(int safe, } else if (s->state == BROTLI_STATE_COMMAND_POST_WRAP_COPY) { goto CommandPostWrapCopy; } else { - return BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE); } CommandBegin: @@ -1555,10 +1616,10 @@ CommandBegin: } if (!CheckInputAmount(safe, br, 28)) { /* 156 bits + 7 bytes */ s->state = BROTLI_STATE_COMMAND_BEGIN; - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } - if (PREDICT_FALSE(s->block_length[1] == 0)) { + if (BROTLI_PREDICT_FALSE(s->block_length[1] == 0)) { BROTLI_SAFE(DecodeCommandBlockSwitch(s)); goto CommandBegin; } @@ -1583,10 +1644,10 @@ CommandInner: do { if (!CheckInputAmount(safe, br, 28)) { /* 162 bits + 7 bytes */ s->state = BROTLI_STATE_COMMAND_INNER; - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } - if (PREDICT_FALSE(s->block_length[0] == 0)) { + if (BROTLI_PREDICT_FALSE(s->block_length[0] == 0)) { BROTLI_SAFE(DecodeLiteralBlockSwitch(s)); PreloadSymbol(safe, s->literal_htree, br, &bits, &value); if (!s->trivial_literal_context) goto CommandInner; @@ -1597,7 +1658,7 @@ CommandInner: } else { uint32_t literal; if (!SafeReadSymbol(s->literal_htree, br, &literal)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } s->ringbuffer[pos] = (uint8_t)literal; @@ -1605,7 +1666,7 @@ CommandInner: --s->block_length[0]; BROTLI_LOG_ARRAY_INDEX(s->ringbuffer, pos); ++pos; - if (PREDICT_FALSE(pos == s->ringbuffer_size)) { + if (BROTLI_PREDICT_FALSE(pos == s->ringbuffer_size)) { s->state = BROTLI_STATE_COMMAND_INNER_WRITE; --i; goto saveStateAndReturn; @@ -1619,10 +1680,10 @@ CommandInner: uint8_t context; if (!CheckInputAmount(safe, br, 28)) { /* 162 bits + 7 bytes */ s->state = BROTLI_STATE_COMMAND_INNER; - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } - if (PREDICT_FALSE(s->block_length[0] == 0)) { + if (BROTLI_PREDICT_FALSE(s->block_length[0] == 0)) { BROTLI_SAFE(DecodeLiteralBlockSwitch(s)); if (s->trivial_literal_context) goto CommandInner; } @@ -1635,7 +1696,7 @@ CommandInner: } else { uint32_t literal; if (!SafeReadSymbol(hc, br, &literal)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; goto saveStateAndReturn; } p1 = (uint8_t)literal; @@ -1645,7 +1706,7 @@ CommandInner: BROTLI_LOG_UINT(s->context_map_slice[context]); BROTLI_LOG_ARRAY_INDEX(s->ringbuffer, pos & s->ringbuffer_mask); ++pos; - if (PREDICT_FALSE(pos == s->ringbuffer_size)) { + if (BROTLI_PREDICT_FALSE(pos == s->ringbuffer_size)) { s->state = BROTLI_STATE_COMMAND_INNER_WRITE; --i; goto saveStateAndReturn; @@ -1653,7 +1714,7 @@ CommandInner: } while (--i != 0); } BROTLI_LOG_UINT(s->meta_block_remaining_len); - if (PREDICT_FALSE(s->meta_block_remaining_len <= 0)) { + if (BROTLI_PREDICT_FALSE(s->meta_block_remaining_len <= 0)) { s->state = BROTLI_STATE_METABLOCK_DONE; goto saveStateAndReturn; } @@ -1663,46 +1724,54 @@ CommandPostDecodeLiterals: s->state = BROTLI_STATE_COMMAND_POST_DECODE_LITERALS; } if (s->distance_code >= 0) { + /* Implicit distance case. */ + s->distance_context = s->distance_code ? 0 : 1; --s->dist_rb_idx; s->distance_code = s->dist_rb[s->dist_rb_idx & 3]; - goto postReadDistance; /* We already have the implicit distance */ - } - /* Read distance code in the command, unless it was implicitly zero. */ - if (PREDICT_FALSE(s->block_length[2] == 0)) { - BROTLI_SAFE(DecodeDistanceBlockSwitch(s)); + } else { + /* Read distance code in the command, unless it was implicitly zero. */ + if (BROTLI_PREDICT_FALSE(s->block_length[2] == 0)) { + BROTLI_SAFE(DecodeDistanceBlockSwitch(s)); + } + BROTLI_SAFE(ReadDistance(s, br)); } - BROTLI_SAFE(ReadDistance(s, br)); -postReadDistance: BROTLI_LOG(("[ProcessCommandsInternal] pos = %d distance = %d\n", pos, s->distance_code)); if (s->max_distance != s->max_backward_distance) { - if (pos < s->max_backward_distance_minus_custom_dict_size) { - s->max_distance = pos + s->custom_dict_size; - } else { - s->max_distance = s->max_backward_distance; - } + s->max_distance = + (pos < s->max_backward_distance) ? pos : s->max_backward_distance; } i = s->copy_length; /* Apply copy of LZ77 back-reference, or static dictionary reference if the distance is larger than the max LZ77 distance */ if (s->distance_code > s->max_distance) { - if (i >= kBrotliMinDictionaryWordLength && - i <= kBrotliMaxDictionaryWordLength) { - int offset = (int)kBrotliDictionaryOffsetsByLength[i]; - int word_id = s->distance_code - s->max_distance - 1; - uint32_t shift = kBrotliDictionarySizeBitsByLength[i]; + int address = s->distance_code - s->max_distance - 1; + if (i >= BROTLI_MIN_DICTIONARY_WORD_LENGTH && + i <= BROTLI_MAX_DICTIONARY_WORD_LENGTH) { + int offset = (int)s->dictionary->offsets_by_length[i]; + uint32_t shift = s->dictionary->size_bits_by_length[i]; int mask = (int)BitMask(shift); - int word_idx = word_id & mask; - int transform_idx = word_id >> shift; + int word_idx = address & mask; + int transform_idx = address >> shift; + /* Compensate double distance-ring-buffer roll. */ + s->dist_rb_idx += s->distance_context; offset += word_idx * i; + if (BROTLI_PREDICT_FALSE(!s->dictionary->data)) { + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_DICTIONARY_NOT_SET); + } if (transform_idx < kNumTransforms) { - const uint8_t* word = &kBrotliDictionary[offset]; + const uint8_t* word = &s->dictionary->data[offset]; int len = i; if (transform_idx == 0) { memcpy(&s->ringbuffer[pos], word, (size_t)len); + BROTLI_LOG(("[ProcessCommandsInternal] dictionary word: [%.*s]\n", + len, word)); } else { len = TransformDictionaryWord( &s->ringbuffer[pos], word, len, transform_idx); + BROTLI_LOG(("[ProcessCommandsInternal] dictionary word: [%.*s]," + " transform_idx = %d, transformed: [%.*s]\n", + i, word, transform_idx, len, &s->ringbuffer[pos])); } pos += len; s->meta_block_remaining_len -= len; @@ -1715,13 +1784,13 @@ postReadDistance: BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " "len: %d bytes left: %d\n", pos, s->distance_code, i, s->meta_block_remaining_len)); - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_TRANSFORM); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_TRANSFORM); } } else { BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " "len: %d bytes left: %d\n", pos, s->distance_code, i, s->meta_block_remaining_len)); - return BROTLI_FAILURE(BROTLI_ERROR_FORMAT_DICTIONARY); + return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_DICTIONARY); } } else { int src_start = (pos - s->distance_code) & s->ringbuffer_mask; @@ -1733,9 +1802,9 @@ postReadDistance: s->dist_rb[s->dist_rb_idx & 3] = s->distance_code; ++s->dist_rb_idx; s->meta_block_remaining_len -= i; - /* There are 32+ bytes of slack in the ringbuffer allocation. + /* There are 32+ bytes of slack in the ring-buffer allocation. Also, we have 16 short codes, that make these 16 bytes irrelevant - in the ringbuffer. Let's copy over them as a first guess. + in the ring-buffer. Let's copy over them as a first guess. */ memmove16(copy_dst, copy_src); if (src_end > pos && dst_end > src_start) { @@ -1772,7 +1841,7 @@ CommandPostWrapCopy: s->ringbuffer[pos] = s->ringbuffer[(pos - s->distance_code) & s->ringbuffer_mask]; ++pos; - if (PREDICT_FALSE(--wrap_guard == 0)) { + if (BROTLI_PREDICT_FALSE(--wrap_guard == 0)) { s->state = BROTLI_STATE_COMMAND_POST_WRITE_2; goto saveStateAndReturn; } @@ -1794,32 +1863,33 @@ saveStateAndReturn: #undef BROTLI_SAFE -static BROTLI_NOINLINE BrotliErrorCode ProcessCommands(BrotliState* s) { +static BROTLI_NOINLINE BrotliDecoderErrorCode ProcessCommands( + BrotliDecoderState* s) { return ProcessCommandsInternal(0, s); } -static BROTLI_NOINLINE BrotliErrorCode SafeProcessCommands(BrotliState* s) { +static BROTLI_NOINLINE BrotliDecoderErrorCode SafeProcessCommands( + BrotliDecoderState* s) { return ProcessCommandsInternal(1, s); } -BrotliResult BrotliDecompressBuffer(size_t encoded_size, - const uint8_t* encoded_buffer, - size_t* decoded_size, - uint8_t* decoded_buffer) { - BrotliState s; - BrotliResult result; +BrotliDecoderResult BrotliDecoderDecompress( + size_t encoded_size, const uint8_t* encoded_buffer, size_t* decoded_size, + uint8_t* decoded_buffer) { + BrotliDecoderState s; + BrotliDecoderResult result; size_t total_out = 0; size_t available_in = encoded_size; const uint8_t* next_in = encoded_buffer; size_t available_out = *decoded_size; uint8_t* next_out = decoded_buffer; - BrotliStateInit(&s); - result = BrotliDecompressStream(&available_in, &next_in, &available_out, - &next_out, &total_out, &s); + BrotliDecoderStateInit(&s); + result = BrotliDecoderDecompressStream( + &s, &available_in, &next_in, &available_out, &next_out, &total_out); *decoded_size = total_out; - BrotliStateCleanup(&s); - if (result != BROTLI_RESULT_SUCCESS) { - result = BROTLI_RESULT_ERROR; + BrotliDecoderStateCleanup(&s); + if (result != BROTLI_DECODER_RESULT_SUCCESS) { + result = BROTLI_DECODER_RESULT_ERROR; } return result; } @@ -1827,7 +1897,7 @@ BrotliResult BrotliDecompressBuffer(size_t encoded_size, /* Invariant: input stream is never overconsumed: * invalid input implies that the whole stream is invalid -> any amount of input could be read and discarded - * when result is "needs more input", then at leat one more byte is REQUIRED + * when result is "needs more input", then at least one more byte is REQUIRED to complete decoding; all input data MUST be consumed by decoder, so client could swap the input buffer * when result is "needs more output" decoder MUST ensure that it doesn't @@ -1836,11 +1906,20 @@ BrotliResult BrotliDecompressBuffer(size_t encoded_size, * when result is "success" decoder MUST return all unused data back to input buffer; this is possible because the invariant is hold on enter */ -BrotliResult BrotliDecompressStream(size_t* available_in, - const uint8_t** next_in, size_t* available_out, uint8_t** next_out, - size_t* total_out, BrotliState* s) { - BrotliErrorCode result = BROTLI_SUCCESS; +BrotliDecoderResult BrotliDecoderDecompressStream( + BrotliDecoderState* s, size_t* available_in, const uint8_t** next_in, + size_t* available_out, uint8_t** next_out, size_t* total_out) { + BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; BrotliBitReader* br = &s->br; + /* Do not try to process further in a case of unrecoverable error. */ + if ((int)s->error_code < 0) { + return BROTLI_DECODER_RESULT_ERROR; + } + if (*available_out && (!next_out || !*next_out)) { + return SaveErrorCode( + s, BROTLI_FAILURE(BROTLI_DECODER_ERROR_INVALID_ARGUMENTS)); + } + if (!*available_out) next_out = 0; if (s->buffer_length == 0) { /* Just connect bit reader to input stream. */ br->avail_in = *available_in; br->next_in = *next_in; @@ -1848,30 +1927,36 @@ BrotliResult BrotliDecompressStream(size_t* available_in, /* At least one byte of input is required. More than one byte of input may be required to complete the transaction -> reading more data must be done in a loop -> do it in a main loop. */ - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; br->next_in = &s->buffer.u8[0]; } /* State machine */ for (;;) { - if (result != BROTLI_SUCCESS) { /* Error | needs more input/output */ - if (result == BROTLI_NEEDS_MORE_INPUT) { - if (s->ringbuffer != 0) { /* Proactively push output. */ - WriteRingBuffer(available_out, next_out, total_out, s); + if (result != BROTLI_DECODER_SUCCESS) { /* Error, needs more input/output */ + if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { + if (s->ringbuffer != 0) { /* Pro-actively push output. */ + BrotliDecoderErrorCode intermediate_result = WriteRingBuffer(s, + available_out, next_out, total_out, BROTLI_TRUE); + /* WriteRingBuffer checks s->meta_block_remaining_len validity. */ + if ((int)intermediate_result < 0) { + result = intermediate_result; + break; + } } if (s->buffer_length != 0) { /* Used with internal buffer. */ if (br->avail_in == 0) { /* Successfully finished read transaction. */ - /* Accamulator contains less than 8 bits, because internal buffer + /* Accumulator contains less than 8 bits, because internal buffer is expanded byte-by-byte until it is enough to complete read. */ s->buffer_length = 0; /* Switch to input stream and restart. */ - result = BROTLI_SUCCESS; + result = BROTLI_DECODER_SUCCESS; br->avail_in = *available_in; br->next_in = *next_in; continue; } else if (*available_in != 0) { /* Not enough data in buffer, but can take one more byte from input stream. */ - result = BROTLI_SUCCESS; + result = BROTLI_DECODER_SUCCESS; s->buffer.u8[s->buffer_length] = **next_in; s->buffer_length++; br->avail_in = s->buffer_length; @@ -1905,8 +1990,8 @@ BrotliResult BrotliDecompressStream(size_t* available_in, s->buffer_length = 0; } else { /* Using input stream in last iteration. When decoder switches to input - stream it has less than 8 bits in accamulator, so it is safe to - return unused accamulator bits there. */ + stream it has less than 8 bits in accumulator, so it is safe to + return unused accumulator bits there. */ BrotliBitReaderUnload(br); *available_in = br->avail_in; *next_in = br->next_in; @@ -1917,7 +2002,7 @@ BrotliResult BrotliDecompressStream(size_t* available_in, case BROTLI_STATE_UNINITED: /* Prepare to the first read. */ if (!BrotliWarmupBitReader(br)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; break; } /* Decode window size. */ @@ -1925,25 +2010,18 @@ BrotliResult BrotliDecompressStream(size_t* available_in, BROTLI_LOG_UINT(s->window_bits); if (s->window_bits == 9) { /* Value 9 is reserved for future use. */ - result = BROTLI_FAILURE(BROTLI_ERROR_FORMAT_WINDOW_BITS); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS); break; } /* Maximum distance, see section 9.1. of the spec. */ - s->max_backward_distance = (1 << s->window_bits) - 16; - /* Limit custom dictionary size. */ - if (s->custom_dict_size >= s->max_backward_distance) { - s->custom_dict += s->custom_dict_size - s->max_backward_distance; - s->custom_dict_size = s->max_backward_distance; - } - s->max_backward_distance_minus_custom_dict_size = - s->max_backward_distance - s->custom_dict_size; + s->max_backward_distance = (1 << s->window_bits) - BROTLI_WINDOW_GAP; /* Allocate memory for both block_type_trees and block_len_trees. */ s->block_type_trees = (HuffmanCode*)BROTLI_ALLOC(s, sizeof(HuffmanCode) * 3 * (BROTLI_HUFFMAN_MAX_SIZE_258 + BROTLI_HUFFMAN_MAX_SIZE_26)); if (s->block_type_trees == 0) { - result = BROTLI_FAILURE(BROTLI_ERROR_ALLOC_BLOCK_TYPE_TREES); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_BLOCK_TYPE_TREES); break; } s->block_len_trees = @@ -1952,13 +2030,13 @@ BrotliResult BrotliDecompressStream(size_t* available_in, s->state = BROTLI_STATE_METABLOCK_BEGIN; /* No break, continue to next state */ case BROTLI_STATE_METABLOCK_BEGIN: - BrotliStateMetablockBegin(s); + BrotliDecoderStateMetablockBegin(s); BROTLI_LOG_UINT(s->pos); s->state = BROTLI_STATE_METABLOCK_HEADER; /* No break, continue to next state */ case BROTLI_STATE_METABLOCK_HEADER: result = DecodeMetaBlockLength(s, br); /* Reads 2 - 31 bits. */ - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } BROTLI_LOG_UINT(s->is_last_metablock); @@ -1967,7 +2045,7 @@ BrotliResult BrotliDecompressStream(size_t* available_in, BROTLI_LOG_UINT(s->is_uncompressed); if (s->is_metadata || s->is_uncompressed) { if (!BrotliJumpToByteBoundary(br)) { - result = BROTLI_FAILURE(BROTLI_ERROR_FORMAT_PADDING_1); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_PADDING_1); break; } } @@ -1979,9 +2057,7 @@ BrotliResult BrotliDecompressStream(size_t* available_in, s->state = BROTLI_STATE_METABLOCK_DONE; break; } - if (!s->ringbuffer) { - BrotliCalculateRingBufferSize(s, br); - } + BrotliCalculateRingBufferSize(s); if (s->is_uncompressed) { s->state = BROTLI_STATE_UNCOMPRESSED; break; @@ -1990,11 +2066,9 @@ BrotliResult BrotliDecompressStream(size_t* available_in, s->state = BROTLI_STATE_HUFFMAN_CODE_0; break; case BROTLI_STATE_UNCOMPRESSED: { - int bytes_copied = s->meta_block_remaining_len; result = CopyUncompressedBlockToOutput( available_out, next_out, total_out, s); - bytes_copied -= s->meta_block_remaining_len; - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } s->state = BROTLI_STATE_METABLOCK_DONE; @@ -2005,11 +2079,11 @@ BrotliResult BrotliDecompressStream(size_t* available_in, uint32_t bits; /* Read one byte and ignore it. */ if (!BrotliSafeReadBits(br, 8, &bits)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; break; } } - if (result == BROTLI_SUCCESS) { + if (result == BROTLI_DECODER_SUCCESS) { s->state = BROTLI_STATE_METABLOCK_DONE; } break; @@ -2020,7 +2094,7 @@ BrotliResult BrotliDecompressStream(size_t* available_in, } /* Reads 1..11 bits. */ result = DecodeVarLenUint8(s, br, &s->num_block_types[s->loop_counter]); - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } s->num_block_types[s->loop_counter]++; @@ -2035,15 +2109,15 @@ BrotliResult BrotliDecompressStream(size_t* available_in, int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_258; result = ReadHuffmanCode(s->num_block_types[s->loop_counter] + 2, &s->block_type_trees[tree_offset], NULL, s); - if (result != BROTLI_SUCCESS) break; + if (result != BROTLI_DECODER_SUCCESS) break; s->state = BROTLI_STATE_HUFFMAN_CODE_2; /* No break, continue to next state */ } case BROTLI_STATE_HUFFMAN_CODE_2: { int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_26; - result = ReadHuffmanCode(kNumBlockLengthCodes, + result = ReadHuffmanCode(BROTLI_NUM_BLOCK_LEN_SYMBOLS, &s->block_len_trees[tree_offset], NULL, s); - if (result != BROTLI_SUCCESS) break; + if (result != BROTLI_DECODER_SUCCESS) break; s->state = BROTLI_STATE_HUFFMAN_CODE_3; /* No break, continue to next state */ } @@ -2051,7 +2125,7 @@ BrotliResult BrotliDecompressStream(size_t* available_in, int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_26; if (!SafeReadBlockLength(s, &s->block_length[s->loop_counter], &s->block_len_trees[tree_offset], br)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; break; } BROTLI_LOG_UINT(s->block_length[s->loop_counter]); @@ -2062,20 +2136,20 @@ BrotliResult BrotliDecompressStream(size_t* available_in, case BROTLI_STATE_METABLOCK_HEADER_2: { uint32_t bits; if (!BrotliSafeReadBits(br, 6, &bits)) { - result = BROTLI_NEEDS_MORE_INPUT; + result = BROTLI_DECODER_NEEDS_MORE_INPUT; break; } s->distance_postfix_bits = bits & BitMask(2); bits >>= 2; - s->num_direct_distance_codes = - NUM_DISTANCE_SHORT_CODES + (bits << s->distance_postfix_bits); + s->num_direct_distance_codes = BROTLI_NUM_DISTANCE_SHORT_CODES + + (bits << s->distance_postfix_bits); BROTLI_LOG_UINT(s->num_direct_distance_codes); BROTLI_LOG_UINT(s->distance_postfix_bits); s->distance_postfix_mask = (int)BitMask(s->distance_postfix_bits); s->context_modes = (uint8_t*)BROTLI_ALLOC(s, (size_t)s->num_block_types[0]); if (s->context_modes == 0) { - result = BROTLI_FAILURE(BROTLI_ERROR_ALLOC_CONTEXT_MODES); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MODES); break; } s->loop_counter = 0; @@ -2084,16 +2158,16 @@ BrotliResult BrotliDecompressStream(size_t* available_in, } case BROTLI_STATE_CONTEXT_MODES: result = ReadContextModes(s); - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } s->state = BROTLI_STATE_CONTEXT_MAP_1; /* No break, continue to next state */ case BROTLI_STATE_CONTEXT_MAP_1: result = DecodeContextMap( - s->num_block_types[0] << kLiteralContextBits, + s->num_block_types[0] << BROTLI_LITERAL_CONTEXT_BITS, &s->num_literal_htrees, &s->context_map, s); - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } DetectTrivialLiteralBlockTypes(s); @@ -2101,26 +2175,27 @@ BrotliResult BrotliDecompressStream(size_t* available_in, /* No break, continue to next state */ case BROTLI_STATE_CONTEXT_MAP_2: { - uint32_t num_distance_codes = - s->num_direct_distance_codes + (48U << s->distance_postfix_bits); + uint32_t num_distance_codes = s->num_direct_distance_codes + + ((2 * BROTLI_MAX_DISTANCE_BITS) << s->distance_postfix_bits); + BROTLI_BOOL allocation_success = BROTLI_TRUE; result = DecodeContextMap( - s->num_block_types[2] << kDistanceContextBits, + s->num_block_types[2] << BROTLI_DISTANCE_CONTEXT_BITS, &s->num_dist_htrees, &s->dist_context_map, s); - if (result != BROTLI_SUCCESS) { + if (result != BROTLI_DECODER_SUCCESS) { break; } - BrotliHuffmanTreeGroupInit(s, &s->literal_hgroup, kNumLiteralCodes, - s->num_literal_htrees); - BrotliHuffmanTreeGroupInit(s, &s->insert_copy_hgroup, - kNumInsertAndCopyCodes, - s->num_block_types[1]); - BrotliHuffmanTreeGroupInit(s, &s->distance_hgroup, num_distance_codes, - s->num_dist_htrees); - if (s->literal_hgroup.codes == 0 || - s->insert_copy_hgroup.codes == 0 || - s->distance_hgroup.codes == 0) { + allocation_success &= BrotliDecoderHuffmanTreeGroupInit( + s, &s->literal_hgroup, BROTLI_NUM_LITERAL_SYMBOLS, + s->num_literal_htrees); + allocation_success &= BrotliDecoderHuffmanTreeGroupInit( + s, &s->insert_copy_hgroup, BROTLI_NUM_COMMAND_SYMBOLS, + s->num_block_types[1]); + allocation_success &= BrotliDecoderHuffmanTreeGroupInit( + s, &s->distance_hgroup, num_distance_codes, + s->num_dist_htrees); + if (!allocation_success) { return SaveErrorCode(s, - BROTLI_FAILURE(BROTLI_ERROR_ALLOC_TREE_GROUPS)); + BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_TREE_GROUPS)); } } s->loop_counter = 0; @@ -2140,19 +2215,19 @@ BrotliResult BrotliDecompressStream(size_t* available_in, hgroup = &s->distance_hgroup; break; default: - return SaveErrorCode(s, - BROTLI_FAILURE(BROTLI_ERROR_UNREACHABLE)); + return SaveErrorCode(s, BROTLI_FAILURE( + BROTLI_DECODER_ERROR_UNREACHABLE)); } result = HuffmanTreeGroupDecode(hgroup, s); } - if (result != BROTLI_SUCCESS) break; + if (result != BROTLI_DECODER_SUCCESS) break; s->loop_counter++; if (s->loop_counter >= 3) { PrepareLiteralDecoding(s); s->dist_context_map_slice = s->dist_context_map; s->htree_command = s->insert_copy_hgroup.htrees[0]; - if (!s->ringbuffer && !BrotliAllocateRingBuffer(s)) { - result = BROTLI_FAILURE(BROTLI_ERROR_ALLOC_RING_BUFFER_2); + if (!BrotliEnsureRingBuffer(s)) { + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2); break; } s->state = BROTLI_STATE_COMMAND_BEGIN; @@ -2163,20 +2238,23 @@ BrotliResult BrotliDecompressStream(size_t* available_in, case BROTLI_STATE_COMMAND_POST_DECODE_LITERALS: case BROTLI_STATE_COMMAND_POST_WRAP_COPY: result = ProcessCommands(s); - if (result == BROTLI_NEEDS_MORE_INPUT) { + if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { result = SafeProcessCommands(s); } break; case BROTLI_STATE_COMMAND_INNER_WRITE: case BROTLI_STATE_COMMAND_POST_WRITE_1: case BROTLI_STATE_COMMAND_POST_WRITE_2: - result = WriteRingBuffer(available_out, next_out, total_out, s); - if (result != BROTLI_SUCCESS) { + result = WriteRingBuffer( + s, available_out, next_out, total_out, BROTLI_FALSE); + if (result != BROTLI_DECODER_SUCCESS) { break; } - s->max_distance = s->max_backward_distance; + WrapRingBuffer(s); + if (s->ringbuffer_size == 1 << s->window_bits) { + s->max_distance = s->max_backward_distance; + } if (s->state == BROTLI_STATE_COMMAND_POST_WRITE_1) { - memcpy(s->ringbuffer, s->ringbuffer_end, (size_t)s->pos); if (s->meta_block_remaining_len == 0) { /* Next metablock, if any */ s->state = BROTLI_STATE_METABLOCK_DONE; @@ -2200,16 +2278,16 @@ BrotliResult BrotliDecompressStream(size_t* available_in, break; case BROTLI_STATE_METABLOCK_DONE: if (s->meta_block_remaining_len < 0) { - result = BROTLI_FAILURE(BROTLI_ERROR_FORMAT_BLOCK_LENGTH_2); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_2); break; } - BrotliStateCleanupAfterMetablock(s); + BrotliDecoderStateCleanupAfterMetablock(s); if (!s->is_last_metablock) { s->state = BROTLI_STATE_METABLOCK_BEGIN; break; } if (!BrotliJumpToByteBoundary(br)) { - result = BROTLI_FAILURE(BROTLI_ERROR_FORMAT_PADDING_2); + result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_PADDING_2); break; } if (s->buffer_length == 0) { @@ -2221,8 +2299,9 @@ BrotliResult BrotliDecompressStream(size_t* available_in, /* No break, continue to next state */ case BROTLI_STATE_DONE: if (s->ringbuffer != 0) { - result = WriteRingBuffer(available_out, next_out, total_out, s); - if (result != BROTLI_SUCCESS) { + result = WriteRingBuffer( + s, available_out, next_out, total_out, BROTLI_TRUE); + if (result != BROTLI_DECODER_SUCCESS) { break; } } @@ -2232,31 +2311,70 @@ BrotliResult BrotliDecompressStream(size_t* available_in, return SaveErrorCode(s, result); } -void BrotliSetCustomDictionary( - size_t size, const uint8_t* dict, BrotliState* s) { - if (size > (1u << 24)) { - return; +BROTLI_BOOL BrotliDecoderHasMoreOutput(const BrotliDecoderState* s) { + /* After unrecoverable error remaining output is considered nonsensical. */ + if ((int)s->error_code < 0) { + return BROTLI_FALSE; } - s->custom_dict = dict; - s->custom_dict_size = (int)size; + return TO_BROTLI_BOOL( + s->ringbuffer != 0 && UnwrittenBytes(s, BROTLI_FALSE) != 0); } -BrotliErrorCode BrotliGetErrorCode(const BrotliState* s) { - return (BrotliErrorCode)s->error_code; +const uint8_t* BrotliDecoderTakeOutput(BrotliDecoderState* s, size_t* size) { + uint8_t* result = 0; + size_t available_out = *size ? *size : 1u << 24; + size_t requested_out = available_out; + BrotliDecoderErrorCode status; + if ((s->ringbuffer == 0) || ((int)s->error_code < 0)) { + *size = 0; + return 0; + } + WrapRingBuffer(s); + status = WriteRingBuffer(s, &available_out, &result, 0, BROTLI_TRUE); + /* Either WriteRingBuffer returns those "success" codes... */ + if (status == BROTLI_DECODER_SUCCESS || + status == BROTLI_DECODER_NEEDS_MORE_OUTPUT) { + *size = requested_out - available_out; + } else { + /* ... or stream is broken. Normally this should be caught by + BrotliDecoderDecompressStream, this is just a safeguard. */ + if ((int)status < 0) SaveErrorCode(s, status); + *size = 0; + result = 0; + } + return result; +} + +BROTLI_BOOL BrotliDecoderIsUsed(const BrotliDecoderState* s) { + return TO_BROTLI_BOOL(s->state != BROTLI_STATE_UNINITED || + BrotliGetAvailableBits(&s->br) != 0); +} + +BROTLI_BOOL BrotliDecoderIsFinished(const BrotliDecoderState* s) { + return TO_BROTLI_BOOL(s->state == BROTLI_STATE_DONE) && + !BrotliDecoderHasMoreOutput(s); } -const char* BrotliErrorString(BrotliErrorCode c) { +BrotliDecoderErrorCode BrotliDecoderGetErrorCode(const BrotliDecoderState* s) { + return (BrotliDecoderErrorCode)s->error_code; +} + +const char* BrotliDecoderErrorString(BrotliDecoderErrorCode c) { switch (c) { -#define _BROTLI_ERROR_CODE_CASE(PREFIX, NAME, CODE) \ - case BROTLI ## PREFIX ## NAME: return #NAME; -#define _BROTLI_NOTHING - BROTLI_ERROR_CODES_LIST(_BROTLI_ERROR_CODE_CASE, _BROTLI_NOTHING) -#undef _BROTLI_ERROR_CODE_CASE -#undef _BROTLI_NOTHING +#define BROTLI_ERROR_CODE_CASE_(PREFIX, NAME, CODE) \ + case BROTLI_DECODER ## PREFIX ## NAME: return #NAME; +#define BROTLI_NOTHING_ + BROTLI_DECODER_ERROR_CODES_LIST(BROTLI_ERROR_CODE_CASE_, BROTLI_NOTHING_) +#undef BROTLI_ERROR_CODE_CASE_ +#undef BROTLI_NOTHING_ default: return "INVALID"; } } +uint32_t BrotliDecoderVersion() { + return BROTLI_VERSION; +} + #if defined(__cplusplus) || defined(c_plusplus) } /* extern "C" */ #endif |