| File: | root/firefox-clang/obj-x86_64-pc-linux-gnu/modules/brotli/./../../../modules/brotli/dec/decode.c |
| Warning: | line 2267, column 15 Value stored to 'dict_id' is never read |
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| 1 | /* Copyright 2013 Google Inc. All Rights Reserved. |
| 2 | |
| 3 | Distributed under MIT license. |
| 4 | See file LICENSE for detail or copy at https://opensource.org/licenses/MIT |
| 5 | */ |
| 6 | |
| 7 | #include <brotli/decode.h> |
| 8 | |
| 9 | #include "../common/constants.h" |
| 10 | #include "../common/context.h" |
| 11 | #include "../common/dictionary.h" |
| 12 | #include "../common/platform.h" |
| 13 | #include "../common/shared_dictionary_internal.h" |
| 14 | #include <brotli/shared_dictionary.h> |
| 15 | #include "../common/transform.h" |
| 16 | #include "../common/version.h" |
| 17 | #include "bit_reader.h" |
| 18 | #include "huffman.h" |
| 19 | #include "prefix.h" |
| 20 | #include "state.h" |
| 21 | #include "static_init.h" |
| 22 | |
| 23 | #if defined(BROTLI_TARGET_NEON) |
| 24 | #include <arm_neon.h> |
| 25 | #endif |
| 26 | |
| 27 | #if defined(__cplusplus) || defined(c_plusplus) |
| 28 | extern "C" { |
| 29 | #endif |
| 30 | |
| 31 | #define BROTLI_FAILURE(CODE)((void)(0), CODE) (BROTLI_DUMP()(void)(0), CODE) |
| 32 | |
| 33 | #define BROTLI_LOG_UINT(name) \ |
| 34 | BROTLI_LOG(("[%s] %s = %lu\n", __func__, #name, (unsigned long)(name))) |
| 35 | #define BROTLI_LOG_ARRAY_INDEX(array_name, idx) \ |
| 36 | BROTLI_LOG(("[%s] %s[%lu] = %lu\n", __func__, #array_name, \ |
| 37 | (unsigned long)(idx), (unsigned long)array_name[idx])) |
| 38 | |
| 39 | #define HUFFMAN_TABLE_BITS8U 8U |
| 40 | #define HUFFMAN_TABLE_MASK0xFF 0xFF |
| 41 | |
| 42 | /* We need the slack region for the following reasons: |
| 43 | - doing up to two 16-byte copies for fast backward copying |
| 44 | - inserting transformed dictionary word: |
| 45 | 255 prefix + 32 base + 255 suffix */ |
| 46 | static const brotli_reg_tuint64_t kRingBufferWriteAheadSlack = 542; |
| 47 | |
| 48 | static const BROTLI_MODEL("small")__attribute__((model("small"))) |
| 49 | uint8_t kCodeLengthCodeOrder[BROTLI_CODE_LENGTH_CODES(17 + 1)] = { |
| 50 | 1, 2, 3, 4, 0, 5, 17, 6, 16, 7, 8, 9, 10, 11, 12, 13, 14, 15, |
| 51 | }; |
| 52 | |
| 53 | /* Static prefix code for the complex code length code lengths. */ |
| 54 | static const BROTLI_MODEL("small")__attribute__((model("small"))) |
| 55 | uint8_t kCodeLengthPrefixLength[16] = { |
| 56 | 2, 2, 2, 3, 2, 2, 2, 4, 2, 2, 2, 3, 2, 2, 2, 4, |
| 57 | }; |
| 58 | |
| 59 | static const BROTLI_MODEL("small")__attribute__((model("small"))) |
| 60 | uint8_t kCodeLengthPrefixValue[16] = { |
| 61 | 0, 4, 3, 2, 0, 4, 3, 1, 0, 4, 3, 2, 0, 4, 3, 5, |
| 62 | }; |
| 63 | |
| 64 | BROTLI_BOOLint BrotliDecoderSetParameter( |
| 65 | BrotliDecoderStateBrotliDecoderStateInternal* state, BrotliDecoderParameter p, uint32_t value) { |
| 66 | if (state->state != BROTLI_STATE_UNINITED) return BROTLI_FALSE0; |
| 67 | switch (p) { |
| 68 | case BROTLI_DECODER_PARAM_DISABLE_RING_BUFFER_REALLOCATION: |
| 69 | state->canny_ringbuffer_allocation = !!value ? 0 : 1; |
| 70 | return BROTLI_TRUE1; |
| 71 | |
| 72 | case BROTLI_DECODER_PARAM_LARGE_WINDOW: |
| 73 | state->large_window = TO_BROTLI_BOOL(!!value)(!!(!!value) ? 1 : 0); |
| 74 | return BROTLI_TRUE1; |
| 75 | |
| 76 | default: return BROTLI_FALSE0; |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | BrotliDecoderStateBrotliDecoderStateInternal* BrotliDecoderCreateInstance( |
| 81 | brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) { |
| 82 | BrotliDecoderStateBrotliDecoderStateInternal* state = 0; |
| 83 | if (!BrotliDecoderEnsureStaticInit()) { |
| 84 | BROTLI_DUMP()(void)(0); |
| 85 | return 0; |
| 86 | } |
| 87 | if (!alloc_func && !free_func) { |
| 88 | state = (BrotliDecoderStateBrotliDecoderStateInternal*)malloc(sizeof(BrotliDecoderStateBrotliDecoderStateInternal)); |
| 89 | } else if (alloc_func && free_func) { |
| 90 | state = (BrotliDecoderStateBrotliDecoderStateInternal*)alloc_func(opaque, sizeof(BrotliDecoderStateBrotliDecoderStateInternal)); |
| 91 | } |
| 92 | if (state == 0) { |
| 93 | BROTLI_DUMP()(void)(0); |
| 94 | return 0; |
| 95 | } |
| 96 | if (!BrotliDecoderStateInit(state, alloc_func, free_func, opaque)) { |
| 97 | BROTLI_DUMP()(void)(0); |
| 98 | if (!alloc_func && !free_func) { |
| 99 | free(state); |
| 100 | } else if (alloc_func && free_func) { |
| 101 | free_func(opaque, state); |
| 102 | } |
| 103 | return 0; |
| 104 | } |
| 105 | return state; |
| 106 | } |
| 107 | |
| 108 | /* Deinitializes and frees BrotliDecoderState instance. */ |
| 109 | void BrotliDecoderDestroyInstance(BrotliDecoderStateBrotliDecoderStateInternal* state) { |
| 110 | if (!state) { |
| 111 | return; |
| 112 | } else { |
| 113 | brotli_free_func free_func = state->free_func; |
| 114 | void* opaque = state->memory_manager_opaque; |
| 115 | BrotliDecoderStateCleanup(state); |
| 116 | free_func(opaque, state); |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | /* Saves error code and converts it to BrotliDecoderResult. */ |
| 121 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderResult SaveErrorCode( |
| 122 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliDecoderErrorCode e, size_t consumed_input) { |
| 123 | s->error_code = (int)e; |
| 124 | s->used_input += consumed_input; |
| 125 | if ((s->buffer_length != 0) && (s->br.next_in == s->br.last_in)) { |
| 126 | /* If internal buffer is depleted at last, reset it. */ |
| 127 | s->buffer_length = 0; |
| 128 | } |
| 129 | switch (e) { |
| 130 | case BROTLI_DECODER_SUCCESS: |
| 131 | return BROTLI_DECODER_RESULT_SUCCESS; |
| 132 | |
| 133 | case BROTLI_DECODER_NEEDS_MORE_INPUT: |
| 134 | return BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT; |
| 135 | |
| 136 | case BROTLI_DECODER_NEEDS_MORE_OUTPUT: |
| 137 | return BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT; |
| 138 | |
| 139 | default: |
| 140 | return BROTLI_DECODER_RESULT_ERROR; |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | /* Decodes WBITS by reading 1 - 7 bits, or 0x11 for "Large Window Brotli". |
| 145 | Precondition: bit-reader accumulator has at least 8 bits. */ |
| 146 | static BrotliDecoderErrorCode DecodeWindowBits(BrotliDecoderStateBrotliDecoderStateInternal* s, |
| 147 | BrotliBitReader* br) { |
| 148 | brotli_reg_tuint64_t n; |
| 149 | BROTLI_BOOLint large_window = s->large_window; |
| 150 | s->large_window = BROTLI_FALSE0; |
| 151 | BrotliTakeBits(br, 1, &n); |
| 152 | if (n == 0) { |
| 153 | s->window_bits = 16; |
| 154 | return BROTLI_DECODER_SUCCESS; |
| 155 | } |
| 156 | BrotliTakeBits(br, 3, &n); |
| 157 | if (n != 0) { |
| 158 | s->window_bits = (17u + n) & 63u; |
| 159 | return BROTLI_DECODER_SUCCESS; |
| 160 | } |
| 161 | BrotliTakeBits(br, 3, &n); |
| 162 | if (n == 1) { |
| 163 | if (large_window) { |
| 164 | BrotliTakeBits(br, 1, &n); |
| 165 | if (n == 1) { |
| 166 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS)((void)(0), BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS); |
| 167 | } |
| 168 | s->large_window = BROTLI_TRUE1; |
| 169 | return BROTLI_DECODER_SUCCESS; |
| 170 | } else { |
| 171 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS)((void)(0), BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS); |
| 172 | } |
| 173 | } |
| 174 | if (n != 0) { |
| 175 | s->window_bits = (8u + n) & 63u; |
| 176 | return BROTLI_DECODER_SUCCESS; |
| 177 | } |
| 178 | s->window_bits = 17; |
| 179 | return BROTLI_DECODER_SUCCESS; |
| 180 | } |
| 181 | |
| 182 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void memmove16(uint8_t* dst, uint8_t* src) { |
| 183 | #if defined(BROTLI_TARGET_NEON) |
| 184 | vst1q_u8(dst, vld1q_u8(src)); |
| 185 | #else |
| 186 | uint32_t buffer[4]; |
| 187 | memcpy(buffer, src, 16); |
| 188 | memcpy(dst, buffer, 16); |
| 189 | #endif |
| 190 | } |
| 191 | |
| 192 | /* Decodes a number in the range [0..255], by reading 1 - 11 bits. */ |
| 193 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode DecodeVarLenUint8( |
| 194 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br, brotli_reg_tuint64_t* value) { |
| 195 | brotli_reg_tuint64_t bits; |
| 196 | switch (s->substate_decode_uint8) { |
| 197 | case BROTLI_STATE_DECODE_UINT8_NONE: |
| 198 | if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, 1, &bits))(__builtin_expect(!BrotliSafeReadBits(br, 1, &bits), 0))) { |
| 199 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 200 | } |
| 201 | if (bits == 0) { |
| 202 | *value = 0; |
| 203 | return BROTLI_DECODER_SUCCESS; |
| 204 | } |
| 205 | /* Fall through. */ |
| 206 | |
| 207 | case BROTLI_STATE_DECODE_UINT8_SHORT: |
| 208 | if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, 3, &bits))(__builtin_expect(!BrotliSafeReadBits(br, 3, &bits), 0))) { |
| 209 | s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_SHORT; |
| 210 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 211 | } |
| 212 | if (bits == 0) { |
| 213 | *value = 1; |
| 214 | s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; |
| 215 | return BROTLI_DECODER_SUCCESS; |
| 216 | } |
| 217 | /* Use output value as a temporary storage. It MUST be persisted. */ |
| 218 | *value = bits; |
| 219 | /* Fall through. */ |
| 220 | |
| 221 | case BROTLI_STATE_DECODE_UINT8_LONG: |
| 222 | if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, *value, &bits))(__builtin_expect(!BrotliSafeReadBits(br, *value, &bits), 0))) { |
| 223 | s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_LONG; |
| 224 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 225 | } |
| 226 | *value = ((brotli_reg_tuint64_t)1U << *value) + bits; |
| 227 | s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; |
| 228 | return BROTLI_DECODER_SUCCESS; |
| 229 | |
| 230 | default: |
| 231 | return |
| 232 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE); /* COV_NF_LINE */ |
| 233 | } |
| 234 | } |
| 235 | |
| 236 | /* Decodes a metablock length and flags by reading 2 - 31 bits. */ |
| 237 | static BrotliDecoderErrorCode BROTLI_NOINLINE__attribute__((__noinline__)) DecodeMetaBlockLength( |
| 238 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br) { |
| 239 | brotli_reg_tuint64_t bits; |
| 240 | int i; |
| 241 | for (;;) { |
| 242 | switch (s->substate_metablock_header) { |
| 243 | case BROTLI_STATE_METABLOCK_HEADER_NONE: |
| 244 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 245 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 246 | } |
| 247 | s->is_last_metablock = bits ? 1 : 0; |
| 248 | s->meta_block_remaining_len = 0; |
| 249 | s->is_uncompressed = 0; |
| 250 | s->is_metadata = 0; |
| 251 | if (!s->is_last_metablock) { |
| 252 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NIBBLES; |
| 253 | break; |
| 254 | } |
| 255 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_EMPTY; |
| 256 | /* Fall through. */ |
| 257 | |
| 258 | case BROTLI_STATE_METABLOCK_HEADER_EMPTY: |
| 259 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 260 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 261 | } |
| 262 | if (bits) { |
| 263 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; |
| 264 | return BROTLI_DECODER_SUCCESS; |
| 265 | } |
| 266 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NIBBLES; |
| 267 | /* Fall through. */ |
| 268 | |
| 269 | case BROTLI_STATE_METABLOCK_HEADER_NIBBLES: |
| 270 | if (!BrotliSafeReadBits(br, 2, &bits)) { |
| 271 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 272 | } |
| 273 | s->size_nibbles = (uint8_t)(bits + 4); |
| 274 | s->loop_counter = 0; |
| 275 | if (bits == 3) { |
| 276 | s->is_metadata = 1; |
| 277 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_RESERVED; |
| 278 | break; |
| 279 | } |
| 280 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_SIZE; |
| 281 | /* Fall through. */ |
| 282 | |
| 283 | case BROTLI_STATE_METABLOCK_HEADER_SIZE: |
| 284 | i = s->loop_counter; |
| 285 | for (; i < (int)s->size_nibbles; ++i) { |
| 286 | if (!BrotliSafeReadBits(br, 4, &bits)) { |
| 287 | s->loop_counter = i; |
| 288 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 289 | } |
| 290 | if (i + 1 == (int)s->size_nibbles && s->size_nibbles > 4 && |
| 291 | bits == 0) { |
| 292 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_NIBBLE)((void)(0), BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_NIBBLE); |
| 293 | } |
| 294 | s->meta_block_remaining_len |= (int)(bits << (i * 4)); |
| 295 | } |
| 296 | s->substate_metablock_header = |
| 297 | BROTLI_STATE_METABLOCK_HEADER_UNCOMPRESSED; |
| 298 | /* Fall through. */ |
| 299 | |
| 300 | case BROTLI_STATE_METABLOCK_HEADER_UNCOMPRESSED: |
| 301 | if (!s->is_last_metablock) { |
| 302 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 303 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 304 | } |
| 305 | s->is_uncompressed = bits ? 1 : 0; |
| 306 | } |
| 307 | ++s->meta_block_remaining_len; |
| 308 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; |
| 309 | return BROTLI_DECODER_SUCCESS; |
| 310 | |
| 311 | case BROTLI_STATE_METABLOCK_HEADER_RESERVED: |
| 312 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 313 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 314 | } |
| 315 | if (bits != 0) { |
| 316 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_RESERVED)((void)(0), BROTLI_DECODER_ERROR_FORMAT_RESERVED); |
| 317 | } |
| 318 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_BYTES; |
| 319 | /* Fall through. */ |
| 320 | |
| 321 | case BROTLI_STATE_METABLOCK_HEADER_BYTES: |
| 322 | if (!BrotliSafeReadBits(br, 2, &bits)) { |
| 323 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 324 | } |
| 325 | if (bits == 0) { |
| 326 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; |
| 327 | return BROTLI_DECODER_SUCCESS; |
| 328 | } |
| 329 | s->size_nibbles = (uint8_t)bits; |
| 330 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_METADATA; |
| 331 | /* Fall through. */ |
| 332 | |
| 333 | case BROTLI_STATE_METABLOCK_HEADER_METADATA: |
| 334 | i = s->loop_counter; |
| 335 | for (; i < (int)s->size_nibbles; ++i) { |
| 336 | if (!BrotliSafeReadBits(br, 8, &bits)) { |
| 337 | s->loop_counter = i; |
| 338 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 339 | } |
| 340 | if (i + 1 == (int)s->size_nibbles && s->size_nibbles > 1 && |
| 341 | bits == 0) { |
| 342 | return BROTLI_FAILURE(((void)(0), BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE ) |
| 343 | BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE)((void)(0), BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE ); |
| 344 | } |
| 345 | s->meta_block_remaining_len |= (int)(bits << (i * 8)); |
| 346 | } |
| 347 | ++s->meta_block_remaining_len; |
| 348 | s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; |
| 349 | return BROTLI_DECODER_SUCCESS; |
| 350 | |
| 351 | default: |
| 352 | return |
| 353 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE); /* COV_NF_LINE */ |
| 354 | } |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | /* Decodes the Huffman code. |
| 359 | This method doesn't read data from the bit reader, BUT drops the amount of |
| 360 | bits that correspond to the decoded symbol. |
| 361 | bits MUST contain at least 15 (BROTLI_HUFFMAN_MAX_CODE_LENGTH) valid bits. */ |
| 362 | static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t DecodeSymbol(brotli_reg_tuint64_t bits, |
| 363 | const HuffmanCode* table, |
| 364 | BrotliBitReader* br) { |
| 365 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table); |
| 366 | BROTLI_HC_ADJUST_TABLE_INDEX(table, bits & HUFFMAN_TABLE_MASK)table += (bits & 0xFF); |
| 367 | if (BROTLI_HC_FAST_LOAD_BITS(table)(table->bits) > HUFFMAN_TABLE_BITS8U) { |
| 368 | brotli_reg_tuint64_t nbits = BROTLI_HC_FAST_LOAD_BITS(table)(table->bits) - HUFFMAN_TABLE_BITS8U; |
| 369 | BrotliDropBits(br, HUFFMAN_TABLE_BITS8U); |
| 370 | BROTLI_HC_ADJUST_TABLE_INDEX(table,table += ((table->value) + ((bits >> 8U) & BitMask (nbits))) |
| 371 | BROTLI_HC_FAST_LOAD_VALUE(table) +table += ((table->value) + ((bits >> 8U) & BitMask (nbits))) |
| 372 | ((bits >> HUFFMAN_TABLE_BITS) & BitMask(nbits)))table += ((table->value) + ((bits >> 8U) & BitMask (nbits))); |
| 373 | } |
| 374 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(table)(table->bits)); |
| 375 | return BROTLI_HC_FAST_LOAD_VALUE(table)(table->value); |
| 376 | } |
| 377 | |
| 378 | /* Reads and decodes the next Huffman code from bit-stream. |
| 379 | This method peeks 16 bits of input and drops 0 - 15 of them. */ |
| 380 | static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t ReadSymbol(const HuffmanCode* table, |
| 381 | BrotliBitReader* br) { |
| 382 | return DecodeSymbol(BrotliGet16BitsUnmasked(br), table, br); |
| 383 | } |
| 384 | |
| 385 | /* Same as DecodeSymbol, but it is known that there is less than 15 bits of |
| 386 | input are currently available. */ |
| 387 | static BROTLI_NOINLINE__attribute__((__noinline__)) BROTLI_BOOLint SafeDecodeSymbol( |
| 388 | const HuffmanCode* table, BrotliBitReader* br, brotli_reg_tuint64_t* result) { |
| 389 | brotli_reg_tuint64_t val; |
| 390 | brotli_reg_tuint64_t available_bits = BrotliGetAvailableBits(br); |
| 391 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table); |
| 392 | if (available_bits == 0) { |
| 393 | if (BROTLI_HC_FAST_LOAD_BITS(table)(table->bits) == 0) { |
| 394 | *result = BROTLI_HC_FAST_LOAD_VALUE(table)(table->value); |
| 395 | return BROTLI_TRUE1; |
| 396 | } |
| 397 | return BROTLI_FALSE0; /* No valid bits at all. */ |
| 398 | } |
| 399 | val = BrotliGetBitsUnmasked(br); |
| 400 | BROTLI_HC_ADJUST_TABLE_INDEX(table, val & HUFFMAN_TABLE_MASK)table += (val & 0xFF); |
| 401 | if (BROTLI_HC_FAST_LOAD_BITS(table)(table->bits) <= HUFFMAN_TABLE_BITS8U) { |
| 402 | if (BROTLI_HC_FAST_LOAD_BITS(table)(table->bits) <= available_bits) { |
| 403 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(table)(table->bits)); |
| 404 | *result = BROTLI_HC_FAST_LOAD_VALUE(table)(table->value); |
| 405 | return BROTLI_TRUE1; |
| 406 | } else { |
| 407 | return BROTLI_FALSE0; /* Not enough bits for the first level. */ |
| 408 | } |
| 409 | } |
| 410 | if (available_bits <= HUFFMAN_TABLE_BITS8U) { |
| 411 | return BROTLI_FALSE0; /* Not enough bits to move to the second level. */ |
| 412 | } |
| 413 | |
| 414 | /* Speculatively drop HUFFMAN_TABLE_BITS. */ |
| 415 | val = (val & BitMask(BROTLI_HC_FAST_LOAD_BITS(table)(table->bits))) >> HUFFMAN_TABLE_BITS8U; |
| 416 | available_bits -= HUFFMAN_TABLE_BITS8U; |
| 417 | BROTLI_HC_ADJUST_TABLE_INDEX(table, BROTLI_HC_FAST_LOAD_VALUE(table) + val)table += ((table->value) + val); |
| 418 | if (available_bits < BROTLI_HC_FAST_LOAD_BITS(table)(table->bits)) { |
| 419 | return BROTLI_FALSE0; /* Not enough bits for the second level. */ |
| 420 | } |
| 421 | |
| 422 | BrotliDropBits(br, HUFFMAN_TABLE_BITS8U + BROTLI_HC_FAST_LOAD_BITS(table)(table->bits)); |
| 423 | *result = BROTLI_HC_FAST_LOAD_VALUE(table)(table->value); |
| 424 | return BROTLI_TRUE1; |
| 425 | } |
| 426 | |
| 427 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadSymbol( |
| 428 | const HuffmanCode* table, BrotliBitReader* br, brotli_reg_tuint64_t* result) { |
| 429 | brotli_reg_tuint64_t val; |
| 430 | if (BROTLI_PREDICT_TRUE(BrotliSafeGetBits(br, 15, &val))(__builtin_expect(!!(BrotliSafeGetBits(br, 15, &val)), 1) )) { |
| 431 | *result = DecodeSymbol(val, table, br); |
| 432 | return BROTLI_TRUE1; |
| 433 | } |
| 434 | return SafeDecodeSymbol(table, br, result); |
| 435 | } |
| 436 | |
| 437 | /* Makes a look-up in first level Huffman table. Peeks 8 bits. */ |
| 438 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void PreloadSymbol(int safe, |
| 439 | const HuffmanCode* table, |
| 440 | BrotliBitReader* br, |
| 441 | brotli_reg_tuint64_t* bits, |
| 442 | brotli_reg_tuint64_t* value) { |
| 443 | if (safe) { |
| 444 | return; |
| 445 | } |
| 446 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table); |
| 447 | BROTLI_HC_ADJUST_TABLE_INDEX(table, BrotliGetBits(br, HUFFMAN_TABLE_BITS))table += (BrotliGetBits(br, 8U)); |
| 448 | *bits = BROTLI_HC_FAST_LOAD_BITS(table)(table->bits); |
| 449 | *value = BROTLI_HC_FAST_LOAD_VALUE(table)(table->value); |
| 450 | } |
| 451 | |
| 452 | /* Decodes the next Huffman code using data prepared by PreloadSymbol. |
| 453 | Reads 0 - 15 bits. Also peeks 8 following bits. */ |
| 454 | static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t ReadPreloadedSymbol(const HuffmanCode* table, |
| 455 | BrotliBitReader* br, |
| 456 | brotli_reg_tuint64_t* bits, |
| 457 | brotli_reg_tuint64_t* value) { |
| 458 | brotli_reg_tuint64_t result = *value; |
| 459 | if (BROTLI_PREDICT_FALSE(*bits > HUFFMAN_TABLE_BITS)(__builtin_expect(*bits > 8U, 0))) { |
| 460 | brotli_reg_tuint64_t val = BrotliGet16BitsUnmasked(br); |
| 461 | const HuffmanCode* ext = table + (val & HUFFMAN_TABLE_MASK0xFF) + *value; |
| 462 | brotli_reg_tuint64_t mask = BitMask((*bits - HUFFMAN_TABLE_BITS8U)); |
| 463 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(ext); |
| 464 | BrotliDropBits(br, HUFFMAN_TABLE_BITS8U); |
| 465 | BROTLI_HC_ADJUST_TABLE_INDEX(ext, (val >> HUFFMAN_TABLE_BITS) & mask)ext += ((val >> 8U) & mask); |
| 466 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(ext)(ext->bits)); |
| 467 | result = BROTLI_HC_FAST_LOAD_VALUE(ext)(ext->value); |
| 468 | } else { |
| 469 | BrotliDropBits(br, *bits); |
| 470 | } |
| 471 | PreloadSymbol(0, table, br, bits, value); |
| 472 | return result; |
| 473 | } |
| 474 | |
| 475 | /* Reads up to limit symbols from br and copies them into ringbuffer, |
| 476 | starting from pos. Caller must ensure that there is enough space |
| 477 | for the write. Returns the amount of symbols actually copied. */ |
| 478 | static BROTLI_INLINEinline __attribute__((__always_inline__)) int BrotliCopyPreloadedSymbolsToU8(const HuffmanCode* table, |
| 479 | BrotliBitReader* br, |
| 480 | brotli_reg_tuint64_t* bits, |
| 481 | brotli_reg_tuint64_t* value, |
| 482 | uint8_t* ringbuffer, |
| 483 | int pos, |
| 484 | const int limit) { |
| 485 | const int kMaximalOverread = 4; |
| 486 | int pos_limit = limit; |
| 487 | int copies = 0; |
| 488 | /* Calculate range where CheckInputAmount is always true. |
| 489 | Start with the number of bytes we can read. */ |
| 490 | int64_t new_lim = br->guard_in - br->next_in; |
| 491 | /* Convert to bits, since symbols use variable number of bits. */ |
| 492 | new_lim *= 8; |
| 493 | /* At most 15 bits per symbol, so this is safe. */ |
| 494 | new_lim /= 15; |
| 495 | if ((new_lim - kMaximalOverread) <= limit) { |
| 496 | // Safe cast, since new_lim is already < num_steps |
| 497 | pos_limit = (int)(new_lim - kMaximalOverread); |
| 498 | } |
| 499 | if (pos_limit < 0) { |
| 500 | pos_limit = 0; |
| 501 | } |
| 502 | copies = pos_limit; |
| 503 | pos_limit += pos; |
| 504 | /* Fast path, caller made sure it is safe to write, |
| 505 | we verified that is is safe to read. */ |
| 506 | for (; pos < pos_limit; pos++) { |
| 507 | BROTLI_DCHECK(BrotliCheckInputAmount(br)); |
| 508 | ringbuffer[pos] = (uint8_t)ReadPreloadedSymbol(table, br, bits, value); |
| 509 | BROTLI_LOG_ARRAY_INDEX(ringbuffer, pos); |
| 510 | } |
| 511 | /* Do the remainder, caller made sure it is safe to write, |
| 512 | we need to bverify that it is safe to read. */ |
| 513 | while (BrotliCheckInputAmount(br) && copies < limit) { |
| 514 | ringbuffer[pos] = (uint8_t)ReadPreloadedSymbol(table, br, bits, value); |
| 515 | BROTLI_LOG_ARRAY_INDEX(ringbuffer, pos); |
| 516 | pos++; |
| 517 | copies++; |
| 518 | } |
| 519 | return copies; |
| 520 | } |
| 521 | |
| 522 | static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t Log2Floor(brotli_reg_tuint64_t x) { |
| 523 | brotli_reg_tuint64_t result = 0; |
| 524 | while (x) { |
| 525 | x >>= 1; |
| 526 | ++result; |
| 527 | } |
| 528 | return result; |
| 529 | } |
| 530 | |
| 531 | /* Reads (s->symbol + 1) symbols. |
| 532 | Totally 1..4 symbols are read, 1..11 bits each. |
| 533 | The list of symbols MUST NOT contain duplicates. */ |
| 534 | static BrotliDecoderErrorCode ReadSimpleHuffmanSymbols( |
| 535 | brotli_reg_tuint64_t alphabet_size_max, brotli_reg_tuint64_t alphabet_size_limit, |
| 536 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 537 | /* max_bits == 1..11; symbol == 0..3; 1..44 bits will be read. */ |
| 538 | BrotliBitReader* br = &s->br; |
| 539 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 540 | brotli_reg_tuint64_t max_bits = Log2Floor(alphabet_size_max - 1); |
| 541 | brotli_reg_tuint64_t i = h->sub_loop_counter; |
| 542 | brotli_reg_tuint64_t num_symbols = h->symbol; |
| 543 | while (i <= num_symbols) { |
| 544 | brotli_reg_tuint64_t v; |
| 545 | if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, max_bits, &v))(__builtin_expect(!BrotliSafeReadBits(br, max_bits, &v), 0 ))) { |
| 546 | h->sub_loop_counter = i; |
| 547 | h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_READ; |
| 548 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 549 | } |
| 550 | if (v >= alphabet_size_limit) { |
| 551 | return |
| 552 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET)((void)(0), BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET ); |
| 553 | } |
| 554 | h->symbols_lists_array[i] = (uint16_t)v; |
| 555 | BROTLI_LOG_UINT(h->symbols_lists_array[i]); |
| 556 | ++i; |
| 557 | } |
| 558 | |
| 559 | for (i = 0; i < num_symbols; ++i) { |
| 560 | brotli_reg_tuint64_t k = i + 1; |
| 561 | for (; k <= num_symbols; ++k) { |
| 562 | if (h->symbols_lists_array[i] == h->symbols_lists_array[k]) { |
| 563 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME)((void)(0), BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME); |
| 564 | } |
| 565 | } |
| 566 | } |
| 567 | |
| 568 | return BROTLI_DECODER_SUCCESS; |
| 569 | } |
| 570 | |
| 571 | /* Process single decoded symbol code length: |
| 572 | A) reset the repeat variable |
| 573 | B) remember code length (if it is not 0) |
| 574 | C) extend corresponding index-chain |
| 575 | D) reduce the Huffman space |
| 576 | E) update the histogram */ |
| 577 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void ProcessSingleCodeLength(brotli_reg_tuint64_t code_len, |
| 578 | brotli_reg_tuint64_t* symbol, brotli_reg_tuint64_t* repeat, brotli_reg_tuint64_t* space, |
| 579 | brotli_reg_tuint64_t* prev_code_len, uint16_t* symbol_lists, |
| 580 | uint16_t* code_length_histo, int* next_symbol) { |
| 581 | *repeat = 0; |
| 582 | if (code_len != 0) { /* code_len == 1..15 */ |
| 583 | symbol_lists[next_symbol[code_len]] = (uint16_t)(*symbol); |
| 584 | next_symbol[code_len] = (int)(*symbol); |
| 585 | *prev_code_len = code_len; |
| 586 | *space -= 32768U >> code_len; |
| 587 | code_length_histo[code_len]++; |
| 588 | BROTLI_LOG(("[ReadHuffmanCode] code_length[%d] = %d\n", |
| 589 | (int)*symbol, (int)code_len)); |
| 590 | } |
| 591 | (*symbol)++; |
| 592 | } |
| 593 | |
| 594 | /* Process repeated symbol code length. |
| 595 | A) Check if it is the extension of previous repeat sequence; if the decoded |
| 596 | value is not BROTLI_REPEAT_PREVIOUS_CODE_LENGTH, then it is a new |
| 597 | symbol-skip |
| 598 | B) Update repeat variable |
| 599 | C) Check if operation is feasible (fits alphabet) |
| 600 | D) For each symbol do the same operations as in ProcessSingleCodeLength |
| 601 | |
| 602 | PRECONDITION: code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH or |
| 603 | code_len == BROTLI_REPEAT_ZERO_CODE_LENGTH */ |
| 604 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void ProcessRepeatedCodeLength(brotli_reg_tuint64_t code_len, |
| 605 | brotli_reg_tuint64_t repeat_delta, brotli_reg_tuint64_t alphabet_size, brotli_reg_tuint64_t* symbol, |
| 606 | brotli_reg_tuint64_t* repeat, brotli_reg_tuint64_t* space, brotli_reg_tuint64_t* prev_code_len, |
| 607 | brotli_reg_tuint64_t* repeat_code_len, uint16_t* symbol_lists, |
| 608 | uint16_t* code_length_histo, int* next_symbol) { |
| 609 | brotli_reg_tuint64_t old_repeat; |
| 610 | brotli_reg_tuint64_t extra_bits = 3; /* for BROTLI_REPEAT_ZERO_CODE_LENGTH */ |
| 611 | brotli_reg_tuint64_t new_len = 0; /* for BROTLI_REPEAT_ZERO_CODE_LENGTH */ |
| 612 | if (code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH16) { |
| 613 | new_len = *prev_code_len; |
| 614 | extra_bits = 2; |
| 615 | } |
| 616 | if (*repeat_code_len != new_len) { |
| 617 | *repeat = 0; |
| 618 | *repeat_code_len = new_len; |
| 619 | } |
| 620 | old_repeat = *repeat; |
| 621 | if (*repeat > 0) { |
| 622 | *repeat -= 2; |
| 623 | *repeat <<= extra_bits; |
| 624 | } |
| 625 | *repeat += repeat_delta + 3U; |
| 626 | repeat_delta = *repeat - old_repeat; |
| 627 | if (*symbol + repeat_delta > alphabet_size) { |
| 628 | BROTLI_DUMP()(void)(0); |
| 629 | *symbol = alphabet_size; |
| 630 | *space = 0xFFFFF; |
| 631 | return; |
| 632 | } |
| 633 | BROTLI_LOG(("[ReadHuffmanCode] code_length[%d..%d] = %d\n", |
| 634 | (int)*symbol, (int)(*symbol + repeat_delta - 1), (int)*repeat_code_len)); |
| 635 | if (*repeat_code_len != 0) { |
| 636 | brotli_reg_tuint64_t last = *symbol + repeat_delta; |
| 637 | int next = next_symbol[*repeat_code_len]; |
| 638 | do { |
| 639 | symbol_lists[next] = (uint16_t)*symbol; |
| 640 | next = (int)*symbol; |
| 641 | } while (++(*symbol) != last); |
| 642 | next_symbol[*repeat_code_len] = next; |
| 643 | *space -= repeat_delta << (15 - *repeat_code_len); |
| 644 | code_length_histo[*repeat_code_len] = |
| 645 | (uint16_t)(code_length_histo[*repeat_code_len] + repeat_delta); |
| 646 | } else { |
| 647 | *symbol += repeat_delta; |
| 648 | } |
| 649 | } |
| 650 | |
| 651 | /* Reads and decodes symbol codelengths. */ |
| 652 | static BrotliDecoderErrorCode ReadSymbolCodeLengths( |
| 653 | brotli_reg_tuint64_t alphabet_size, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 654 | BrotliBitReader* br = &s->br; |
| 655 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 656 | brotli_reg_tuint64_t symbol = h->symbol; |
| 657 | brotli_reg_tuint64_t repeat = h->repeat; |
| 658 | brotli_reg_tuint64_t space = h->space; |
| 659 | brotli_reg_tuint64_t prev_code_len = h->prev_code_len; |
| 660 | brotli_reg_tuint64_t repeat_code_len = h->repeat_code_len; |
| 661 | uint16_t* symbol_lists = h->symbol_lists; |
| 662 | uint16_t* code_length_histo = h->code_length_histo; |
| 663 | int* next_symbol = h->next_symbol; |
| 664 | if (!BrotliWarmupBitReader(br)) { |
| 665 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 666 | } |
| 667 | while (symbol < alphabet_size && space > 0) { |
| 668 | const HuffmanCode* p = h->table; |
| 669 | brotli_reg_tuint64_t code_len; |
| 670 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(p); |
| 671 | if (!BrotliCheckInputAmount(br)) { |
| 672 | h->symbol = symbol; |
| 673 | h->repeat = repeat; |
| 674 | h->prev_code_len = prev_code_len; |
| 675 | h->repeat_code_len = repeat_code_len; |
| 676 | h->space = space; |
| 677 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 678 | } |
| 679 | BrotliFillBitWindow16(br); |
| 680 | BROTLI_HC_ADJUST_TABLE_INDEX(p, BrotliGetBitsUnmasked(br) &p += (BrotliGetBitsUnmasked(br) & BitMask(5)) |
| 681 | BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH))p += (BrotliGetBitsUnmasked(br) & BitMask(5)); |
| 682 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p)(p->bits)); /* Use 1..5 bits. */ |
| 683 | code_len = BROTLI_HC_FAST_LOAD_VALUE(p)(p->value); /* code_len == 0..17 */ |
| 684 | if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH16) { |
| 685 | ProcessSingleCodeLength(code_len, &symbol, &repeat, &space, |
| 686 | &prev_code_len, symbol_lists, code_length_histo, next_symbol); |
| 687 | } else { /* code_len == 16..17, extra_bits == 2..3 */ |
| 688 | brotli_reg_tuint64_t extra_bits = |
| 689 | (code_len == BROTLI_REPEAT_PREVIOUS_CODE_LENGTH16) ? 2 : 3; |
| 690 | brotli_reg_tuint64_t repeat_delta = |
| 691 | BrotliGetBitsUnmasked(br) & BitMask(extra_bits); |
| 692 | BrotliDropBits(br, extra_bits); |
| 693 | ProcessRepeatedCodeLength(code_len, repeat_delta, alphabet_size, |
| 694 | &symbol, &repeat, &space, &prev_code_len, &repeat_code_len, |
| 695 | symbol_lists, code_length_histo, next_symbol); |
| 696 | } |
| 697 | } |
| 698 | h->space = space; |
| 699 | return BROTLI_DECODER_SUCCESS; |
| 700 | } |
| 701 | |
| 702 | static BrotliDecoderErrorCode SafeReadSymbolCodeLengths( |
| 703 | brotli_reg_tuint64_t alphabet_size, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 704 | BrotliBitReader* br = &s->br; |
| 705 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 706 | BROTLI_BOOLint get_byte = BROTLI_FALSE0; |
| 707 | while (h->symbol < alphabet_size && h->space > 0) { |
| 708 | const HuffmanCode* p = h->table; |
| 709 | brotli_reg_tuint64_t code_len; |
| 710 | brotli_reg_tuint64_t available_bits; |
| 711 | brotli_reg_tuint64_t bits = 0; |
| 712 | BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(p); |
| 713 | if (get_byte && !BrotliPullByte(br)) return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 714 | get_byte = BROTLI_FALSE0; |
| 715 | available_bits = BrotliGetAvailableBits(br); |
| 716 | if (available_bits != 0) { |
| 717 | bits = (uint32_t)BrotliGetBitsUnmasked(br); |
| 718 | } |
| 719 | BROTLI_HC_ADJUST_TABLE_INDEX(p,p += (bits & BitMask(5)) |
| 720 | bits & BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH))p += (bits & BitMask(5)); |
| 721 | if (BROTLI_HC_FAST_LOAD_BITS(p)(p->bits) > available_bits) { |
| 722 | get_byte = BROTLI_TRUE1; |
| 723 | continue; |
| 724 | } |
| 725 | code_len = BROTLI_HC_FAST_LOAD_VALUE(p)(p->value); /* code_len == 0..17 */ |
| 726 | if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH16) { |
| 727 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p)(p->bits)); |
| 728 | ProcessSingleCodeLength(code_len, &h->symbol, &h->repeat, &h->space, |
| 729 | &h->prev_code_len, h->symbol_lists, h->code_length_histo, |
| 730 | h->next_symbol); |
| 731 | } else { /* code_len == 16..17, extra_bits == 2..3 */ |
| 732 | brotli_reg_tuint64_t extra_bits = code_len - 14U; |
| 733 | brotli_reg_tuint64_t repeat_delta = (bits >> BROTLI_HC_FAST_LOAD_BITS(p)(p->bits)) & |
| 734 | BitMask(extra_bits); |
| 735 | if (available_bits < BROTLI_HC_FAST_LOAD_BITS(p)(p->bits) + extra_bits) { |
| 736 | get_byte = BROTLI_TRUE1; |
| 737 | continue; |
| 738 | } |
| 739 | BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p)(p->bits) + extra_bits); |
| 740 | ProcessRepeatedCodeLength(code_len, repeat_delta, alphabet_size, |
| 741 | &h->symbol, &h->repeat, &h->space, &h->prev_code_len, |
| 742 | &h->repeat_code_len, h->symbol_lists, h->code_length_histo, |
| 743 | h->next_symbol); |
| 744 | } |
| 745 | } |
| 746 | return BROTLI_DECODER_SUCCESS; |
| 747 | } |
| 748 | |
| 749 | /* Reads and decodes 15..18 codes using static prefix code. |
| 750 | Each code is 2..4 bits long. In total 30..72 bits are used. */ |
| 751 | static BrotliDecoderErrorCode ReadCodeLengthCodeLengths(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 752 | BrotliBitReader* br = &s->br; |
| 753 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 754 | brotli_reg_tuint64_t num_codes = h->repeat; |
| 755 | brotli_reg_tuint64_t space = h->space; |
| 756 | brotli_reg_tuint64_t i = h->sub_loop_counter; |
| 757 | for (; i < BROTLI_CODE_LENGTH_CODES(17 + 1); ++i) { |
| 758 | const uint8_t code_len_idx = kCodeLengthCodeOrder[i]; |
| 759 | brotli_reg_tuint64_t ix; |
| 760 | brotli_reg_tuint64_t v; |
| 761 | if (BROTLI_PREDICT_FALSE(!BrotliSafeGetBits(br, 4, &ix))(__builtin_expect(!BrotliSafeGetBits(br, 4, &ix), 0))) { |
| 762 | brotli_reg_tuint64_t available_bits = BrotliGetAvailableBits(br); |
| 763 | if (available_bits != 0) { |
| 764 | ix = BrotliGetBitsUnmasked(br) & 0xF; |
| 765 | } else { |
| 766 | ix = 0; |
| 767 | } |
| 768 | if (kCodeLengthPrefixLength[ix] > available_bits) { |
| 769 | h->sub_loop_counter = i; |
| 770 | h->repeat = num_codes; |
| 771 | h->space = space; |
| 772 | h->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX; |
| 773 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 774 | } |
| 775 | } |
| 776 | v = kCodeLengthPrefixValue[ix]; |
| 777 | BrotliDropBits(br, kCodeLengthPrefixLength[ix]); |
| 778 | h->code_length_code_lengths[code_len_idx] = (uint8_t)v; |
| 779 | BROTLI_LOG_ARRAY_INDEX(h->code_length_code_lengths, code_len_idx); |
| 780 | if (v != 0) { |
| 781 | space = space - (32U >> v); |
| 782 | ++num_codes; |
| 783 | ++h->code_length_histo[v]; |
| 784 | if (space - 1U >= 32U) { |
| 785 | /* space is 0 or wrapped around. */ |
| 786 | break; |
| 787 | } |
| 788 | } |
| 789 | } |
| 790 | if (!(num_codes == 1 || space == 0)) { |
| 791 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_CL_SPACE)((void)(0), BROTLI_DECODER_ERROR_FORMAT_CL_SPACE); |
| 792 | } |
| 793 | return BROTLI_DECODER_SUCCESS; |
| 794 | } |
| 795 | |
| 796 | /* Decodes the Huffman tables. |
| 797 | There are 2 scenarios: |
| 798 | A) Huffman code contains only few symbols (1..4). Those symbols are read |
| 799 | directly; their code lengths are defined by the number of symbols. |
| 800 | For this scenario 4 - 49 bits will be read. |
| 801 | |
| 802 | B) 2-phase decoding: |
| 803 | B.1) Small Huffman table is decoded; it is specified with code lengths |
| 804 | encoded with predefined entropy code. 32 - 74 bits are used. |
| 805 | B.2) Decoded table is used to decode code lengths of symbols in resulting |
| 806 | Huffman table. In worst case 3520 bits are read. */ |
| 807 | static BrotliDecoderErrorCode ReadHuffmanCode(brotli_reg_tuint64_t alphabet_size_max, |
| 808 | brotli_reg_tuint64_t alphabet_size_limit, |
| 809 | HuffmanCode* table, |
| 810 | brotli_reg_tuint64_t* opt_table_size, |
| 811 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 812 | BrotliBitReader* br = &s->br; |
| 813 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 814 | /* State machine. */ |
| 815 | for (;;) { |
| 816 | switch (h->substate_huffman) { |
| 817 | case BROTLI_STATE_HUFFMAN_NONE: |
| 818 | if (!BrotliSafeReadBits(br, 2, &h->sub_loop_counter)) { |
| 819 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 820 | } |
| 821 | BROTLI_LOG_UINT(h->sub_loop_counter); |
| 822 | /* The value is used as follows: |
| 823 | 1 for simple code; |
| 824 | 0 for no skipping, 2 skips 2 code lengths, 3 skips 3 code lengths */ |
| 825 | if (h->sub_loop_counter != 1) { |
| 826 | h->space = 32; |
| 827 | h->repeat = 0; /* num_codes */ |
| 828 | memset(&h->code_length_histo[0], 0, sizeof(h->code_length_histo[0]) * |
| 829 | (BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH5 + 1)); |
| 830 | memset(&h->code_length_code_lengths[0], 0, |
| 831 | sizeof(h->code_length_code_lengths)); |
| 832 | h->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX; |
| 833 | continue; |
| 834 | } |
| 835 | /* Fall through. */ |
| 836 | |
| 837 | case BROTLI_STATE_HUFFMAN_SIMPLE_SIZE: |
| 838 | /* Read symbols, codes & code lengths directly. */ |
| 839 | if (!BrotliSafeReadBits(br, 2, &h->symbol)) { /* num_symbols */ |
| 840 | h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_SIZE; |
| 841 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 842 | } |
| 843 | h->sub_loop_counter = 0; |
| 844 | /* Fall through. */ |
| 845 | |
| 846 | case BROTLI_STATE_HUFFMAN_SIMPLE_READ: { |
| 847 | BrotliDecoderErrorCode result = |
| 848 | ReadSimpleHuffmanSymbols(alphabet_size_max, alphabet_size_limit, s); |
| 849 | if (result != BROTLI_DECODER_SUCCESS) { |
| 850 | return result; |
| 851 | } |
| 852 | } |
| 853 | /* Fall through. */ |
| 854 | |
| 855 | case BROTLI_STATE_HUFFMAN_SIMPLE_BUILD: { |
| 856 | brotli_reg_tuint64_t table_size; |
| 857 | if (h->symbol == 3) { |
| 858 | brotli_reg_tuint64_t bits; |
| 859 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 860 | h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_BUILD; |
| 861 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 862 | } |
| 863 | h->symbol += bits; |
| 864 | } |
| 865 | BROTLI_LOG_UINT(h->symbol); |
| 866 | table_size = BrotliBuildSimpleHuffmanTable(table, HUFFMAN_TABLE_BITS8U, |
| 867 | h->symbols_lists_array, |
| 868 | (uint32_t)h->symbol); |
| 869 | if (opt_table_size) { |
| 870 | *opt_table_size = table_size; |
| 871 | } |
| 872 | h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; |
| 873 | return BROTLI_DECODER_SUCCESS; |
| 874 | } |
| 875 | |
| 876 | /* Decode Huffman-coded code lengths. */ |
| 877 | case BROTLI_STATE_HUFFMAN_COMPLEX: { |
| 878 | brotli_reg_tuint64_t i; |
| 879 | BrotliDecoderErrorCode result = ReadCodeLengthCodeLengths(s); |
| 880 | if (result != BROTLI_DECODER_SUCCESS) { |
| 881 | return result; |
| 882 | } |
| 883 | BrotliBuildCodeLengthsHuffmanTable(h->table, |
| 884 | h->code_length_code_lengths, |
| 885 | h->code_length_histo); |
| 886 | memset(&h->code_length_histo[0], 0, sizeof(h->code_length_histo)); |
| 887 | for (i = 0; i <= BROTLI_HUFFMAN_MAX_CODE_LENGTH15; ++i) { |
| 888 | h->next_symbol[i] = (int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH15 + 1); |
| 889 | h->symbol_lists[h->next_symbol[i]] = 0xFFFF; |
| 890 | } |
| 891 | |
| 892 | h->symbol = 0; |
| 893 | h->prev_code_len = BROTLI_INITIAL_REPEATED_CODE_LENGTH8; |
| 894 | h->repeat = 0; |
| 895 | h->repeat_code_len = 0; |
| 896 | h->space = 32768; |
| 897 | h->substate_huffman = BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS; |
| 898 | } |
| 899 | /* Fall through. */ |
| 900 | |
| 901 | case BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS: { |
| 902 | brotli_reg_tuint64_t table_size; |
| 903 | BrotliDecoderErrorCode result = ReadSymbolCodeLengths( |
| 904 | alphabet_size_limit, s); |
| 905 | if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { |
| 906 | result = SafeReadSymbolCodeLengths(alphabet_size_limit, s); |
| 907 | } |
| 908 | if (result != BROTLI_DECODER_SUCCESS) { |
| 909 | return result; |
| 910 | } |
| 911 | |
| 912 | if (h->space != 0) { |
| 913 | BROTLI_LOG(("[ReadHuffmanCode] space = %d\n", (int)h->space)); |
| 914 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_HUFFMAN_SPACE)((void)(0), BROTLI_DECODER_ERROR_FORMAT_HUFFMAN_SPACE); |
| 915 | } |
| 916 | table_size = BrotliBuildHuffmanTable( |
| 917 | table, HUFFMAN_TABLE_BITS8U, h->symbol_lists, h->code_length_histo); |
| 918 | if (opt_table_size) { |
| 919 | *opt_table_size = table_size; |
| 920 | } |
| 921 | h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; |
| 922 | return BROTLI_DECODER_SUCCESS; |
| 923 | } |
| 924 | |
| 925 | default: |
| 926 | return |
| 927 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE); /* COV_NF_LINE */ |
| 928 | } |
| 929 | } |
| 930 | } |
| 931 | |
| 932 | /* Decodes a block length by reading 3..39 bits. */ |
| 933 | static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t ReadBlockLength(const HuffmanCode* table, |
| 934 | BrotliBitReader* br) { |
| 935 | brotli_reg_tuint64_t code; |
| 936 | brotli_reg_tuint64_t nbits; |
| 937 | code = ReadSymbol(table, br); |
| 938 | nbits = _kBrotliPrefixCodeRanges[code].nbits; /* nbits == 2..24 */ |
| 939 | return _kBrotliPrefixCodeRanges[code].offset + BrotliReadBits24(br, nbits); |
| 940 | } |
| 941 | |
| 942 | /* WARNING: if state is not BROTLI_STATE_READ_BLOCK_LENGTH_NONE, then |
| 943 | reading can't be continued with ReadBlockLength. */ |
| 944 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadBlockLength( |
| 945 | BrotliDecoderStateBrotliDecoderStateInternal* s, brotli_reg_tuint64_t* result, const HuffmanCode* table, |
| 946 | BrotliBitReader* br) { |
| 947 | brotli_reg_tuint64_t index; |
| 948 | if (s->substate_read_block_length == BROTLI_STATE_READ_BLOCK_LENGTH_NONE) { |
| 949 | if (!SafeReadSymbol(table, br, &index)) { |
| 950 | return BROTLI_FALSE0; |
| 951 | } |
| 952 | } else { |
| 953 | index = s->block_length_index; |
| 954 | } |
| 955 | { |
| 956 | brotli_reg_tuint64_t bits; |
| 957 | brotli_reg_tuint64_t nbits = _kBrotliPrefixCodeRanges[index].nbits; |
| 958 | brotli_reg_tuint64_t offset = _kBrotliPrefixCodeRanges[index].offset; |
| 959 | if (!BrotliSafeReadBits(br, nbits, &bits)) { |
| 960 | s->block_length_index = index; |
| 961 | s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_SUFFIX; |
| 962 | return BROTLI_FALSE0; |
| 963 | } |
| 964 | *result = offset + bits; |
| 965 | s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; |
| 966 | return BROTLI_TRUE1; |
| 967 | } |
| 968 | } |
| 969 | |
| 970 | /* Transform: |
| 971 | 1) initialize list L with values 0, 1,... 255 |
| 972 | 2) For each input element X: |
| 973 | 2.1) let Y = L[X] |
| 974 | 2.2) remove X-th element from L |
| 975 | 2.3) prepend Y to L |
| 976 | 2.4) append Y to output |
| 977 | |
| 978 | In most cases max(Y) <= 7, so most of L remains intact. |
| 979 | To reduce the cost of initialization, we reuse L, remember the upper bound |
| 980 | of Y values, and reinitialize only first elements in L. |
| 981 | |
| 982 | Most of input values are 0 and 1. To reduce number of branches, we replace |
| 983 | inner for loop with do-while. */ |
| 984 | static BROTLI_NOINLINE__attribute__((__noinline__)) void InverseMoveToFrontTransform( |
| 985 | uint8_t* v, brotli_reg_tuint64_t v_len, BrotliDecoderStateBrotliDecoderStateInternal* state) { |
| 986 | /* Reinitialize elements that could have been changed. */ |
| 987 | brotli_reg_tuint64_t i = 1; |
| 988 | brotli_reg_tuint64_t upper_bound = state->mtf_upper_bound; |
| 989 | uint32_t* mtf = &state->mtf[1]; /* Make mtf[-1] addressable. */ |
| 990 | uint8_t* mtf_u8 = (uint8_t*)mtf; |
| 991 | /* Load endian-aware constant. */ |
| 992 | const uint8_t b0123[4] = {0, 1, 2, 3}; |
| 993 | uint32_t pattern; |
| 994 | memcpy(&pattern, &b0123, 4); |
| 995 | |
| 996 | /* Initialize list using 4 consequent values pattern. */ |
| 997 | mtf[0] = pattern; |
| 998 | do { |
| 999 | pattern += 0x04040404; /* Advance all 4 values by 4. */ |
| 1000 | mtf[i] = pattern; |
| 1001 | i++; |
| 1002 | } while (i <= upper_bound); |
| 1003 | |
| 1004 | /* Transform the input. */ |
| 1005 | upper_bound = 0; |
| 1006 | for (i = 0; i < v_len; ++i) { |
| 1007 | int index = v[i]; |
| 1008 | uint8_t value = mtf_u8[index]; |
| 1009 | upper_bound |= v[i]; |
| 1010 | v[i] = value; |
| 1011 | mtf_u8[-1] = value; |
| 1012 | do { |
| 1013 | index--; |
| 1014 | mtf_u8[index + 1] = mtf_u8[index]; |
| 1015 | } while (index >= 0); |
| 1016 | } |
| 1017 | /* Remember amount of elements to be reinitialized. */ |
| 1018 | state->mtf_upper_bound = upper_bound >> 2; |
| 1019 | } |
| 1020 | |
| 1021 | /* Decodes a series of Huffman table using ReadHuffmanCode function. */ |
| 1022 | static BrotliDecoderErrorCode HuffmanTreeGroupDecode( |
| 1023 | HuffmanTreeGroup* group, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1024 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 1025 | if (h->substate_tree_group != BROTLI_STATE_TREE_GROUP_LOOP) { |
| 1026 | h->next = group->codes; |
| 1027 | h->htree_index = 0; |
| 1028 | h->substate_tree_group = BROTLI_STATE_TREE_GROUP_LOOP; |
| 1029 | } |
| 1030 | while (h->htree_index < group->num_htrees) { |
| 1031 | brotli_reg_tuint64_t table_size; |
| 1032 | BrotliDecoderErrorCode result = ReadHuffmanCode(group->alphabet_size_max, |
| 1033 | group->alphabet_size_limit, h->next, &table_size, s); |
| 1034 | if (result != BROTLI_DECODER_SUCCESS) return result; |
| 1035 | group->htrees[h->htree_index] = h->next; |
| 1036 | h->next += table_size; |
| 1037 | ++h->htree_index; |
| 1038 | } |
| 1039 | h->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE; |
| 1040 | return BROTLI_DECODER_SUCCESS; |
| 1041 | } |
| 1042 | |
| 1043 | /* Decodes a context map. |
| 1044 | Decoding is done in 4 phases: |
| 1045 | 1) Read auxiliary information (6..16 bits) and allocate memory. |
| 1046 | In case of trivial context map, decoding is finished at this phase. |
| 1047 | 2) Decode Huffman table using ReadHuffmanCode function. |
| 1048 | This table will be used for reading context map items. |
| 1049 | 3) Read context map items; "0" values could be run-length encoded. |
| 1050 | 4) Optionally, apply InverseMoveToFront transform to the resulting map. */ |
| 1051 | static BrotliDecoderErrorCode DecodeContextMap(brotli_reg_tuint64_t context_map_size, |
| 1052 | brotli_reg_tuint64_t* num_htrees, |
| 1053 | uint8_t** context_map_arg, |
| 1054 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1055 | BrotliBitReader* br = &s->br; |
| 1056 | BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; |
| 1057 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 1058 | |
| 1059 | switch ((int)h->substate_context_map) { |
| 1060 | case BROTLI_STATE_CONTEXT_MAP_NONE: |
| 1061 | result = DecodeVarLenUint8(s, br, num_htrees); |
| 1062 | if (result != BROTLI_DECODER_SUCCESS) { |
| 1063 | return result; |
| 1064 | } |
| 1065 | (*num_htrees)++; |
| 1066 | h->context_index = 0; |
| 1067 | BROTLI_LOG_UINT(context_map_size); |
| 1068 | BROTLI_LOG_UINT(*num_htrees); |
| 1069 | *context_map_arg = |
| 1070 | (uint8_t*)BROTLI_DECODER_ALLOC(s, (size_t)context_map_size)s->alloc_func(s->memory_manager_opaque, (size_t)context_map_size ); |
| 1071 | if (*context_map_arg == 0) { |
| 1072 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MAP)((void)(0), BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MAP); |
| 1073 | } |
| 1074 | if (*num_htrees <= 1) { |
| 1075 | memset(*context_map_arg, 0, (size_t)context_map_size); |
| 1076 | return BROTLI_DECODER_SUCCESS; |
| 1077 | } |
| 1078 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_READ_PREFIX; |
| 1079 | /* Fall through. */ |
| 1080 | |
| 1081 | case BROTLI_STATE_CONTEXT_MAP_READ_PREFIX: { |
| 1082 | brotli_reg_tuint64_t bits; |
| 1083 | /* In next stage ReadHuffmanCode uses at least 4 bits, so it is safe |
| 1084 | to peek 4 bits ahead. */ |
| 1085 | if (!BrotliSafeGetBits(br, 5, &bits)) { |
| 1086 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1087 | } |
| 1088 | if ((bits & 1) != 0) { /* Use RLE for zeros. */ |
| 1089 | h->max_run_length_prefix = (bits >> 1) + 1; |
| 1090 | BrotliDropBits(br, 5); |
| 1091 | } else { |
| 1092 | h->max_run_length_prefix = 0; |
| 1093 | BrotliDropBits(br, 1); |
| 1094 | } |
| 1095 | BROTLI_LOG_UINT(h->max_run_length_prefix); |
| 1096 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_HUFFMAN; |
| 1097 | } |
| 1098 | /* Fall through. */ |
| 1099 | |
| 1100 | case BROTLI_STATE_CONTEXT_MAP_HUFFMAN: { |
| 1101 | brotli_reg_tuint64_t alphabet_size = *num_htrees + h->max_run_length_prefix; |
| 1102 | result = ReadHuffmanCode(alphabet_size, alphabet_size, |
| 1103 | h->context_map_table, NULL((void*)0), s); |
| 1104 | if (result != BROTLI_DECODER_SUCCESS) return result; |
| 1105 | h->code = 0xFFFF; |
| 1106 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_DECODE; |
| 1107 | } |
| 1108 | /* Fall through. */ |
| 1109 | |
| 1110 | case BROTLI_STATE_CONTEXT_MAP_DECODE: { |
| 1111 | brotli_reg_tuint64_t context_index = h->context_index; |
| 1112 | brotli_reg_tuint64_t max_run_length_prefix = h->max_run_length_prefix; |
| 1113 | uint8_t* context_map = *context_map_arg; |
| 1114 | brotli_reg_tuint64_t code = h->code; |
| 1115 | BROTLI_BOOLint skip_preamble = (code != 0xFFFF); |
| 1116 | while (context_index < context_map_size || skip_preamble) { |
| 1117 | if (!skip_preamble) { |
| 1118 | if (!SafeReadSymbol(h->context_map_table, br, &code)) { |
| 1119 | h->code = 0xFFFF; |
| 1120 | h->context_index = context_index; |
| 1121 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1122 | } |
| 1123 | BROTLI_LOG_UINT(code); |
| 1124 | |
| 1125 | if (code == 0) { |
| 1126 | context_map[context_index++] = 0; |
| 1127 | continue; |
| 1128 | } |
| 1129 | if (code > max_run_length_prefix) { |
| 1130 | context_map[context_index++] = |
| 1131 | (uint8_t)(code - max_run_length_prefix); |
| 1132 | continue; |
| 1133 | } |
| 1134 | } else { |
| 1135 | skip_preamble = BROTLI_FALSE0; |
| 1136 | } |
| 1137 | /* RLE sub-stage. */ |
| 1138 | { |
| 1139 | brotli_reg_tuint64_t reps; |
| 1140 | if (!BrotliSafeReadBits(br, code, &reps)) { |
| 1141 | h->code = code; |
| 1142 | h->context_index = context_index; |
| 1143 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1144 | } |
| 1145 | reps += (brotli_reg_tuint64_t)1U << code; |
| 1146 | BROTLI_LOG_UINT(reps); |
| 1147 | if (context_index + reps > context_map_size) { |
| 1148 | return |
| 1149 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_CONTEXT_MAP_REPEAT)((void)(0), BROTLI_DECODER_ERROR_FORMAT_CONTEXT_MAP_REPEAT); |
| 1150 | } |
| 1151 | do { |
| 1152 | context_map[context_index++] = 0; |
| 1153 | } while (--reps); |
| 1154 | } |
| 1155 | } |
| 1156 | } |
| 1157 | /* Fall through. */ |
| 1158 | |
| 1159 | case BROTLI_STATE_CONTEXT_MAP_TRANSFORM: { |
| 1160 | brotli_reg_tuint64_t bits; |
| 1161 | if (!BrotliSafeReadBits(br, 1, &bits)) { |
| 1162 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_TRANSFORM; |
| 1163 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1164 | } |
| 1165 | if (bits != 0) { |
| 1166 | InverseMoveToFrontTransform(*context_map_arg, context_map_size, s); |
| 1167 | } |
| 1168 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE; |
| 1169 | return BROTLI_DECODER_SUCCESS; |
| 1170 | } |
| 1171 | |
| 1172 | default: |
| 1173 | return |
| 1174 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE); /* COV_NF_LINE */ |
| 1175 | } |
| 1176 | } |
| 1177 | |
| 1178 | /* Decodes a command or literal and updates block type ring-buffer. |
| 1179 | Reads 3..54 bits. */ |
| 1180 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BrotliDecoderErrorCode DecodeBlockTypeAndLength( |
| 1181 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s, int tree_type) { |
| 1182 | brotli_reg_tuint64_t max_block_type = s->num_block_types[tree_type]; |
| 1183 | const HuffmanCode* type_tree = &s->block_type_trees[ |
| 1184 | tree_type * BROTLI_HUFFMAN_MAX_SIZE_258632]; |
| 1185 | const HuffmanCode* len_tree = &s->block_len_trees[ |
| 1186 | tree_type * BROTLI_HUFFMAN_MAX_SIZE_26396]; |
| 1187 | BrotliBitReader* br = &s->br; |
| 1188 | brotli_reg_tuint64_t* ringbuffer = &s->block_type_rb[tree_type * 2]; |
| 1189 | brotli_reg_tuint64_t block_type; |
| 1190 | if (max_block_type <= 1) { |
| 1191 | return BROTLI_DECODER_ERROR_FORMAT_BLOCK_SWITCH; |
| 1192 | } |
| 1193 | |
| 1194 | /* Read 0..15 + 3..39 bits. */ |
| 1195 | if (!safe) { |
| 1196 | block_type = ReadSymbol(type_tree, br); |
| 1197 | s->block_length[tree_type] = ReadBlockLength(len_tree, br); |
| 1198 | } else { |
| 1199 | BrotliBitReaderState memento; |
| 1200 | BrotliBitReaderSaveState(br, &memento); |
| 1201 | if (!SafeReadSymbol(type_tree, br, &block_type)) { |
| 1202 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1203 | } |
| 1204 | if (!SafeReadBlockLength(s, &s->block_length[tree_type], len_tree, br)) { |
| 1205 | s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; |
| 1206 | BrotliBitReaderRestoreState(br, &memento); |
| 1207 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1208 | } |
| 1209 | } |
| 1210 | |
| 1211 | if (block_type == 1) { |
| 1212 | block_type = ringbuffer[1] + 1; |
| 1213 | } else if (block_type == 0) { |
| 1214 | block_type = ringbuffer[0]; |
| 1215 | } else { |
| 1216 | block_type -= 2; |
| 1217 | } |
| 1218 | if (block_type >= max_block_type) { |
| 1219 | block_type -= max_block_type; |
| 1220 | } |
| 1221 | ringbuffer[0] = ringbuffer[1]; |
| 1222 | ringbuffer[1] = block_type; |
| 1223 | return BROTLI_DECODER_SUCCESS; |
| 1224 | } |
| 1225 | |
| 1226 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void DetectTrivialLiteralBlockTypes( |
| 1227 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1228 | size_t i; |
| 1229 | for (i = 0; i < 8; ++i) s->trivial_literal_contexts[i] = 0; |
| 1230 | for (i = 0; i < s->num_block_types[0]; i++) { |
| 1231 | size_t offset = i << BROTLI_LITERAL_CONTEXT_BITS6; |
| 1232 | size_t error = 0; |
| 1233 | size_t sample = s->context_map[offset]; |
| 1234 | size_t j; |
| 1235 | for (j = 0; j < (1u << BROTLI_LITERAL_CONTEXT_BITS6);) { |
| 1236 | /* NOLINTNEXTLINE(bugprone-macro-repeated-side-effects) */ |
| 1237 | BROTLI_REPEAT_4({ error |= s->context_map[offset + j++] ^ sample; }){{ error |= s->context_map[offset + j++] ^ sample; }; { error |= s->context_map[offset + j++] ^ sample; }; { error |= s ->context_map[offset + j++] ^ sample; }; { error |= s-> context_map[offset + j++] ^ sample; };} |
| 1238 | } |
| 1239 | if (error == 0) { |
| 1240 | s->trivial_literal_contexts[i >> 5] |= 1u << (i & 31); |
| 1241 | } |
| 1242 | } |
| 1243 | } |
| 1244 | |
| 1245 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void PrepareLiteralDecoding(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1246 | uint8_t context_mode; |
| 1247 | size_t trivial; |
| 1248 | brotli_reg_tuint64_t block_type = s->block_type_rb[1]; |
| 1249 | brotli_reg_tuint64_t context_offset = block_type << BROTLI_LITERAL_CONTEXT_BITS6; |
| 1250 | s->context_map_slice = s->context_map + context_offset; |
| 1251 | trivial = s->trivial_literal_contexts[block_type >> 5]; |
| 1252 | s->trivial_literal_context = (trivial >> (block_type & 31)) & 1; |
| 1253 | s->literal_htree = s->literal_hgroup.htrees[s->context_map_slice[0]]; |
| 1254 | context_mode = s->context_modes[block_type] & 3; |
| 1255 | s->context_lookup = BROTLI_CONTEXT_LUT(context_mode)(&_kBrotliContextLookupTable[(context_mode) << 9]); |
| 1256 | } |
| 1257 | |
| 1258 | /* Decodes the block type and updates the state for literal context. |
| 1259 | Reads 3..54 bits. */ |
| 1260 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BrotliDecoderErrorCode DecodeLiteralBlockSwitchInternal( |
| 1261 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1262 | BrotliDecoderErrorCode result = DecodeBlockTypeAndLength(safe, s, 0); |
| 1263 | if (result != BROTLI_DECODER_SUCCESS) { |
| 1264 | return result; |
| 1265 | } |
| 1266 | PrepareLiteralDecoding(s); |
| 1267 | return BROTLI_DECODER_SUCCESS; |
| 1268 | } |
| 1269 | |
| 1270 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode |
| 1271 | DecodeLiteralBlockSwitch(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1272 | return DecodeLiteralBlockSwitchInternal(0, s); |
| 1273 | } |
| 1274 | |
| 1275 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode SafeDecodeLiteralBlockSwitch( |
| 1276 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1277 | return DecodeLiteralBlockSwitchInternal(1, s); |
| 1278 | } |
| 1279 | |
| 1280 | /* Block switch for insert/copy length. |
| 1281 | Reads 3..54 bits. */ |
| 1282 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BrotliDecoderErrorCode DecodeCommandBlockSwitchInternal( |
| 1283 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1284 | BrotliDecoderErrorCode result = DecodeBlockTypeAndLength(safe, s, 1); |
| 1285 | if (result != BROTLI_DECODER_SUCCESS) { |
| 1286 | return result; |
| 1287 | } |
| 1288 | s->htree_command = s->insert_copy_hgroup.htrees[s->block_type_rb[3]]; |
| 1289 | return BROTLI_DECODER_SUCCESS; |
| 1290 | } |
| 1291 | |
| 1292 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode |
| 1293 | DecodeCommandBlockSwitch(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1294 | return DecodeCommandBlockSwitchInternal(0, s); |
| 1295 | } |
| 1296 | |
| 1297 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode |
| 1298 | SafeDecodeCommandBlockSwitch(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1299 | return DecodeCommandBlockSwitchInternal(1, s); |
| 1300 | } |
| 1301 | |
| 1302 | /* Block switch for distance codes. |
| 1303 | Reads 3..54 bits. */ |
| 1304 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BrotliDecoderErrorCode DecodeDistanceBlockSwitchInternal( |
| 1305 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1306 | BrotliDecoderErrorCode result = DecodeBlockTypeAndLength(safe, s, 2); |
| 1307 | if (result != BROTLI_DECODER_SUCCESS) { |
| 1308 | return result; |
| 1309 | } |
| 1310 | s->dist_context_map_slice = s->dist_context_map + |
| 1311 | (s->block_type_rb[5] << BROTLI_DISTANCE_CONTEXT_BITS2); |
| 1312 | s->dist_htree_index = s->dist_context_map_slice[s->distance_context]; |
| 1313 | return BROTLI_DECODER_SUCCESS; |
| 1314 | } |
| 1315 | |
| 1316 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode |
| 1317 | DecodeDistanceBlockSwitch(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1318 | return DecodeDistanceBlockSwitchInternal(0, s); |
| 1319 | } |
| 1320 | |
| 1321 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode SafeDecodeDistanceBlockSwitch( |
| 1322 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1323 | return DecodeDistanceBlockSwitchInternal(1, s); |
| 1324 | } |
| 1325 | |
| 1326 | static size_t UnwrittenBytes(const BrotliDecoderStateBrotliDecoderStateInternal* s, BROTLI_BOOLint wrap) { |
| 1327 | size_t pos = wrap && s->pos > s->ringbuffer_size ? |
| 1328 | (size_t)s->ringbuffer_size : (size_t)(s->pos); |
| 1329 | size_t partial_pos_rb = (s->rb_roundtrips * (size_t)s->ringbuffer_size) + pos; |
| 1330 | return partial_pos_rb - s->partial_pos_out; |
| 1331 | } |
| 1332 | |
| 1333 | /* Dumps output. |
| 1334 | Returns BROTLI_DECODER_NEEDS_MORE_OUTPUT only if there is more output to push |
| 1335 | and either ring-buffer is as big as window size, or |force| is true. */ |
| 1336 | static BrotliDecoderErrorCode BROTLI_NOINLINE__attribute__((__noinline__)) WriteRingBuffer( |
| 1337 | BrotliDecoderStateBrotliDecoderStateInternal* s, size_t* available_out, uint8_t** next_out, |
| 1338 | size_t* total_out, BROTLI_BOOLint force) { |
| 1339 | uint8_t* start = |
| 1340 | s->ringbuffer + (s->partial_pos_out & (size_t)s->ringbuffer_mask); |
| 1341 | size_t to_write = UnwrittenBytes(s, BROTLI_TRUE1); |
| 1342 | size_t num_written = *available_out; |
| 1343 | if (num_written > to_write) { |
| 1344 | num_written = to_write; |
| 1345 | } |
| 1346 | if (s->meta_block_remaining_len < 0) { |
| 1347 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_1)((void)(0), BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_1); |
| 1348 | } |
| 1349 | if (next_out && !*next_out) { |
| 1350 | *next_out = start; |
| 1351 | } else { |
| 1352 | if (next_out) { |
| 1353 | memcpy(*next_out, start, num_written); |
| 1354 | *next_out += num_written; |
| 1355 | } |
| 1356 | } |
| 1357 | *available_out -= num_written; |
| 1358 | BROTLI_LOG_UINT(to_write); |
| 1359 | BROTLI_LOG_UINT(num_written); |
| 1360 | s->partial_pos_out += num_written; |
| 1361 | if (total_out) { |
| 1362 | *total_out = s->partial_pos_out; |
| 1363 | } |
| 1364 | if (num_written < to_write) { |
| 1365 | if (s->ringbuffer_size == (1 << s->window_bits) || force) { |
| 1366 | return BROTLI_DECODER_NEEDS_MORE_OUTPUT; |
| 1367 | } else { |
| 1368 | return BROTLI_DECODER_SUCCESS; |
| 1369 | } |
| 1370 | } |
| 1371 | /* Wrap ring buffer only if it has reached its maximal size. */ |
| 1372 | if (s->ringbuffer_size == (1 << s->window_bits) && |
| 1373 | s->pos >= s->ringbuffer_size) { |
| 1374 | s->pos -= s->ringbuffer_size; |
| 1375 | s->rb_roundtrips++; |
| 1376 | s->should_wrap_ringbuffer = (size_t)s->pos != 0 ? 1 : 0; |
| 1377 | } |
| 1378 | return BROTLI_DECODER_SUCCESS; |
| 1379 | } |
| 1380 | |
| 1381 | static void BROTLI_NOINLINE__attribute__((__noinline__)) WrapRingBuffer(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1382 | if (s->should_wrap_ringbuffer) { |
| 1383 | memcpy(s->ringbuffer, s->ringbuffer_end, (size_t)s->pos); |
| 1384 | s->should_wrap_ringbuffer = 0; |
| 1385 | } |
| 1386 | } |
| 1387 | |
| 1388 | /* Allocates ring-buffer. |
| 1389 | |
| 1390 | s->ringbuffer_size MUST be updated by BrotliCalculateRingBufferSize before |
| 1391 | this function is called. |
| 1392 | |
| 1393 | Last two bytes of ring-buffer are initialized to 0, so context calculation |
| 1394 | could be done uniformly for the first two and all other positions. */ |
| 1395 | static BROTLI_BOOLint BROTLI_NOINLINE__attribute__((__noinline__)) BrotliEnsureRingBuffer( |
| 1396 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1397 | uint8_t* old_ringbuffer = s->ringbuffer; |
| 1398 | if (s->ringbuffer_size == s->new_ringbuffer_size) { |
| 1399 | return BROTLI_TRUE1; |
| 1400 | } |
| 1401 | |
| 1402 | s->ringbuffer = (uint8_t*)BROTLI_DECODER_ALLOC(s,s->alloc_func(s->memory_manager_opaque, (size_t)(s-> new_ringbuffer_size) + kRingBufferWriteAheadSlack) |
| 1403 | (size_t)(s->new_ringbuffer_size) + kRingBufferWriteAheadSlack)s->alloc_func(s->memory_manager_opaque, (size_t)(s-> new_ringbuffer_size) + kRingBufferWriteAheadSlack); |
| 1404 | if (s->ringbuffer == 0) { |
| 1405 | /* Restore previous value. */ |
| 1406 | s->ringbuffer = old_ringbuffer; |
| 1407 | return BROTLI_FALSE0; |
| 1408 | } |
| 1409 | s->ringbuffer[s->new_ringbuffer_size - 2] = 0; |
| 1410 | s->ringbuffer[s->new_ringbuffer_size - 1] = 0; |
| 1411 | |
| 1412 | if (!!old_ringbuffer) { |
| 1413 | memcpy(s->ringbuffer, old_ringbuffer, (size_t)s->pos); |
| 1414 | BROTLI_DECODER_FREE(s, old_ringbuffer){ s->free_func(s->memory_manager_opaque, old_ringbuffer ); old_ringbuffer = ((void*)0); }; |
| 1415 | } |
| 1416 | |
| 1417 | s->ringbuffer_size = s->new_ringbuffer_size; |
| 1418 | s->ringbuffer_mask = s->new_ringbuffer_size - 1; |
| 1419 | s->ringbuffer_end = s->ringbuffer + s->ringbuffer_size; |
| 1420 | |
| 1421 | return BROTLI_TRUE1; |
| 1422 | } |
| 1423 | |
| 1424 | static BrotliDecoderErrorCode BROTLI_NOINLINE__attribute__((__noinline__)) |
| 1425 | SkipMetadataBlock(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1426 | BrotliBitReader* br = &s->br; |
| 1427 | int nbytes; |
| 1428 | |
| 1429 | if (s->meta_block_remaining_len == 0) { |
| 1430 | return BROTLI_DECODER_SUCCESS; |
| 1431 | } |
| 1432 | |
| 1433 | BROTLI_DCHECK((BrotliGetAvailableBits(br) & 7) == 0); |
| 1434 | |
| 1435 | /* Drain accumulator. */ |
| 1436 | if (BrotliGetAvailableBits(br) >= 8) { |
| 1437 | uint8_t buffer[8]; |
| 1438 | nbytes = (int)(BrotliGetAvailableBits(br)) >> 3; |
| 1439 | BROTLI_DCHECK(nbytes <= 8); |
| 1440 | if (nbytes > s->meta_block_remaining_len) { |
| 1441 | nbytes = s->meta_block_remaining_len; |
| 1442 | } |
| 1443 | BrotliCopyBytes(buffer, br, (size_t)nbytes); |
| 1444 | if (s->metadata_chunk_func) { |
| 1445 | s->metadata_chunk_func(s->metadata_callback_opaque, buffer, |
| 1446 | (size_t)nbytes); |
| 1447 | } |
| 1448 | s->meta_block_remaining_len -= nbytes; |
| 1449 | if (s->meta_block_remaining_len == 0) { |
| 1450 | return BROTLI_DECODER_SUCCESS; |
| 1451 | } |
| 1452 | } |
| 1453 | |
| 1454 | /* Direct access to metadata is possible. */ |
| 1455 | nbytes = (int)BrotliGetRemainingBytes(br); |
| 1456 | if (nbytes > s->meta_block_remaining_len) { |
| 1457 | nbytes = s->meta_block_remaining_len; |
| 1458 | } |
| 1459 | if (nbytes > 0) { |
| 1460 | if (s->metadata_chunk_func) { |
| 1461 | s->metadata_chunk_func(s->metadata_callback_opaque, br->next_in, |
| 1462 | (size_t)nbytes); |
| 1463 | } |
| 1464 | BrotliDropBytes(br, (size_t)nbytes); |
| 1465 | s->meta_block_remaining_len -= nbytes; |
| 1466 | if (s->meta_block_remaining_len == 0) { |
| 1467 | return BROTLI_DECODER_SUCCESS; |
| 1468 | } |
| 1469 | } |
| 1470 | |
| 1471 | BROTLI_DCHECK(BrotliGetRemainingBytes(br) == 0); |
| 1472 | |
| 1473 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1474 | } |
| 1475 | |
| 1476 | static BrotliDecoderErrorCode BROTLI_NOINLINE__attribute__((__noinline__)) CopyUncompressedBlockToOutput( |
| 1477 | size_t* available_out, uint8_t** next_out, size_t* total_out, |
| 1478 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1479 | /* TODO(eustas): avoid allocation for single uncompressed block. */ |
| 1480 | if (!BrotliEnsureRingBuffer(s)) { |
| 1481 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_1)((void)(0), BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_1); |
| 1482 | } |
| 1483 | |
| 1484 | /* State machine */ |
| 1485 | for (;;) { |
| 1486 | switch (s->substate_uncompressed) { |
| 1487 | case BROTLI_STATE_UNCOMPRESSED_NONE: { |
| 1488 | int nbytes = (int)BrotliGetRemainingBytes(&s->br); |
| 1489 | if (nbytes > s->meta_block_remaining_len) { |
| 1490 | nbytes = s->meta_block_remaining_len; |
| 1491 | } |
| 1492 | if (s->pos + nbytes > s->ringbuffer_size) { |
| 1493 | nbytes = s->ringbuffer_size - s->pos; |
| 1494 | } |
| 1495 | /* Copy remaining bytes from s->br.buf_ to ring-buffer. */ |
| 1496 | BrotliCopyBytes(&s->ringbuffer[s->pos], &s->br, (size_t)nbytes); |
| 1497 | s->pos += nbytes; |
| 1498 | s->meta_block_remaining_len -= nbytes; |
| 1499 | if (s->pos < 1 << s->window_bits) { |
| 1500 | if (s->meta_block_remaining_len == 0) { |
| 1501 | return BROTLI_DECODER_SUCCESS; |
| 1502 | } |
| 1503 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1504 | } |
| 1505 | s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_WRITE; |
| 1506 | } |
| 1507 | /* Fall through. */ |
| 1508 | |
| 1509 | case BROTLI_STATE_UNCOMPRESSED_WRITE: { |
| 1510 | BrotliDecoderErrorCode result; |
| 1511 | result = WriteRingBuffer( |
| 1512 | s, available_out, next_out, total_out, BROTLI_FALSE0); |
| 1513 | if (result != BROTLI_DECODER_SUCCESS) { |
| 1514 | return result; |
| 1515 | } |
| 1516 | if (s->ringbuffer_size == 1 << s->window_bits) { |
| 1517 | s->max_distance = s->max_backward_distance; |
| 1518 | } |
| 1519 | s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE; |
| 1520 | break; |
| 1521 | } |
| 1522 | } |
| 1523 | } |
| 1524 | BROTLI_DCHECK(0); /* Unreachable */ |
| 1525 | } |
| 1526 | |
| 1527 | static BROTLI_BOOLint AttachCompoundDictionary( |
| 1528 | BrotliDecoderStateBrotliDecoderStateInternal* state, const uint8_t* data, size_t size) { |
| 1529 | BrotliDecoderCompoundDictionary* addon = state->compound_dictionary; |
| 1530 | /* Soft lie: no dictionary is attached; i.e. this call is not accounted |
| 1531 | * towards SHARED_BROTLI_MAX_COMPOUND_DICTS limit. */ |
| 1532 | if (size == 0) return BROTLI_TRUE1; |
| 1533 | if (size > SHARED_BROTLI_MAX_RAW_DICT_SIZE(1u << (23u + sizeof(size_t)))) return BROTLI_FALSE0; |
| 1534 | if (state->state != BROTLI_STATE_UNINITED) return BROTLI_FALSE0; |
| 1535 | if (!addon) { |
| 1536 | addon = (BrotliDecoderCompoundDictionary*)BROTLI_DECODER_ALLOC(state->alloc_func(state->memory_manager_opaque, sizeof( BrotliDecoderCompoundDictionary)) |
| 1537 | state, sizeof(BrotliDecoderCompoundDictionary))state->alloc_func(state->memory_manager_opaque, sizeof( BrotliDecoderCompoundDictionary)); |
| 1538 | if (!addon) return BROTLI_FALSE0; |
| 1539 | addon->num_chunks = 0u; |
| 1540 | addon->block_bits = 255u; |
| 1541 | addon->br_index = 0u; |
| 1542 | addon->total_size = 0u; |
| 1543 | addon->br_offset = 0u; |
| 1544 | addon->br_length = 0u; |
| 1545 | addon->br_copied = 0u; |
| 1546 | addon->chunk_offsets[0] = 0u; |
| 1547 | state->compound_dictionary = addon; |
| 1548 | } |
| 1549 | if (addon->num_chunks == SHARED_BROTLI_MAX_COMPOUND_DICTS15) { |
| 1550 | return BROTLI_FALSE0; |
| 1551 | } |
| 1552 | if (size > SHARED_BROTLI_MAX_RAW_DICT_SIZE(1u << (23u + sizeof(size_t))) - addon->total_size) { |
| 1553 | return BROTLI_FALSE0; |
| 1554 | } |
| 1555 | addon->chunks[addon->num_chunks] = data; |
| 1556 | addon->num_chunks++; |
| 1557 | addon->total_size += (uint32_t)size; |
| 1558 | addon->chunk_offsets[addon->num_chunks] = addon->total_size; |
| 1559 | return BROTLI_TRUE1; |
| 1560 | } |
| 1561 | |
| 1562 | static void EnsureCompoundDictionaryInitialized(BrotliDecoderStateBrotliDecoderStateInternal* state) { |
| 1563 | BrotliDecoderCompoundDictionary* addon = state->compound_dictionary; |
| 1564 | /* 256 = (1 << 8) slots in block map. */ |
| 1565 | size_t block_bits = 8u; |
| 1566 | uint32_t cursor = 0u; |
| 1567 | size_t index = 0u; |
| 1568 | uint32_t maximal_address = addon->total_size - 1u; |
| 1569 | BROTLI_DCHECK(addon->total_size > 0u); |
| 1570 | if (addon->block_bits != 255u) return; |
| 1571 | while ((maximal_address >> block_bits) != 0u) block_bits++; |
| 1572 | block_bits -= 8u; |
| 1573 | addon->block_bits = (uint8_t)block_bits; |
| 1574 | while (cursor <= maximal_address) { |
| 1575 | /* We have sentinel value equal maximal_address + 1. */ |
| 1576 | while (addon->chunk_offsets[index + 1u] < cursor) index++; |
| 1577 | addon->block_map[cursor >> block_bits] = (uint8_t)index; |
| 1578 | cursor += 1u << block_bits; |
| 1579 | } |
| 1580 | /* Now if X is in the range [0..maximal_address] then |
| 1581 | * block_map[X >> block_bits] is in [0..num_chunks). */ |
| 1582 | } |
| 1583 | |
| 1584 | static BROTLI_BOOLint InitializeCompoundDictionaryCopy(BrotliDecoderStateBrotliDecoderStateInternal* s, |
| 1585 | uint32_t address, uint32_t length) { |
| 1586 | BrotliDecoderCompoundDictionary* addon = s->compound_dictionary; |
| 1587 | size_t index; |
| 1588 | BROTLI_DCHECK(addon->total_size > 0u); |
| 1589 | BROTLI_DCHECK(address < addon->total_size); |
| 1590 | BROTLI_DCHECK(length > 0u); |
| 1591 | EnsureCompoundDictionaryInitialized(s); |
| 1592 | index = addon->block_map[address >> addon->block_bits]; |
| 1593 | /* Several chunks might be mapped to the same block index. */ |
| 1594 | while (address >= addon->chunk_offsets[index + 1]) index++; |
| 1595 | /* Check that the whole chunk is within dictionary bounds. */ |
| 1596 | if (length > addon->total_size - address) return BROTLI_FALSE0; |
| 1597 | /* Update the recent distances cache. */ |
| 1598 | s->dist_rb[s->dist_rb_idx & 3] = s->distance_code; |
| 1599 | ++s->dist_rb_idx; |
| 1600 | s->meta_block_remaining_len -= (int)length; |
| 1601 | addon->br_index = (uint16_t)index; |
| 1602 | addon->br_offset = address - addon->chunk_offsets[index]; |
| 1603 | addon->br_length = length; |
| 1604 | addon->br_copied = 0u; |
| 1605 | return BROTLI_TRUE1; |
| 1606 | } |
| 1607 | |
| 1608 | static uint32_t GetCompoundDictionarySize(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1609 | return s->compound_dictionary ? s->compound_dictionary->total_size : 0u; |
| 1610 | } |
| 1611 | |
| 1612 | static int CopyFromCompoundDictionary(BrotliDecoderStateBrotliDecoderStateInternal* s, int pos) { |
| 1613 | BrotliDecoderCompoundDictionary* addon = s->compound_dictionary; |
| 1614 | int orig_pos = pos; |
| 1615 | while (addon->br_length != addon->br_copied) { |
| 1616 | uint8_t* copy_dst = &s->ringbuffer[pos]; |
| 1617 | const uint8_t* copy_src = |
| 1618 | addon->chunks[addon->br_index] + addon->br_offset; |
| 1619 | int space = s->ringbuffer_size - pos; |
| 1620 | uint32_t rem_chunk_length = (addon->chunk_offsets[addon->br_index + 1] - |
| 1621 | addon->chunk_offsets[addon->br_index]) - |
| 1622 | addon->br_offset; |
| 1623 | uint32_t length = addon->br_length - addon->br_copied; |
| 1624 | if (length > rem_chunk_length) length = rem_chunk_length; |
| 1625 | if (length > (uint32_t)space) length = (uint32_t)space; |
| 1626 | memcpy(copy_dst, copy_src, (size_t)length); |
| 1627 | pos += (int)length; |
| 1628 | addon->br_offset += length; |
| 1629 | addon->br_copied += length; |
| 1630 | if (length == rem_chunk_length) { |
| 1631 | addon->br_index++; |
| 1632 | addon->br_offset = 0u; |
| 1633 | } |
| 1634 | if (pos == s->ringbuffer_size) break; |
| 1635 | } |
| 1636 | return pos - orig_pos; |
| 1637 | } |
| 1638 | |
| 1639 | BROTLI_BOOLint BrotliDecoderAttachDictionary( |
| 1640 | BrotliDecoderStateBrotliDecoderStateInternal* state, BrotliSharedDictionaryType type, |
| 1641 | size_t data_size, const uint8_t data[BROTLI_ARRAY_PARAM(data_size)]) { |
| 1642 | brotli_reg_tuint64_t i; |
| 1643 | brotli_reg_tuint64_t num_prefix_before = state->dictionary->num_prefix; |
| 1644 | if (state->state != BROTLI_STATE_UNINITED) return BROTLI_FALSE0; |
| 1645 | if (!BrotliSharedDictionaryAttach(state->dictionary, type, data_size, data)) { |
| 1646 | return BROTLI_FALSE0; |
| 1647 | } |
| 1648 | for (i = num_prefix_before; i < state->dictionary->num_prefix; i++) { |
| 1649 | if (!AttachCompoundDictionary( |
| 1650 | state, state->dictionary->prefix[i], |
| 1651 | state->dictionary->prefix_size[i])) { |
| 1652 | return BROTLI_FALSE0; |
| 1653 | } |
| 1654 | } |
| 1655 | return BROTLI_TRUE1; |
| 1656 | } |
| 1657 | |
| 1658 | /* Calculates the smallest feasible ring buffer. |
| 1659 | |
| 1660 | If we know the data size is small, do not allocate more ring buffer |
| 1661 | size than needed to reduce memory usage. |
| 1662 | |
| 1663 | When this method is called, metablock size and flags MUST be decoded. */ |
| 1664 | static void BROTLI_NOINLINE__attribute__((__noinline__)) BrotliCalculateRingBufferSize( |
| 1665 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1666 | int window_size = 1 << s->window_bits; |
| 1667 | int new_ringbuffer_size = window_size; |
| 1668 | /* We need at least 2 bytes of ring buffer size to get the last two |
| 1669 | bytes for context from there */ |
| 1670 | int min_size = s->ringbuffer_size ? s->ringbuffer_size : 1024; |
| 1671 | int output_size; |
| 1672 | |
| 1673 | /* If maximum is already reached, no further extension is retired. */ |
| 1674 | if (s->ringbuffer_size == window_size) { |
| 1675 | return; |
| 1676 | } |
| 1677 | |
| 1678 | /* Metadata blocks does not touch ring buffer. */ |
| 1679 | if (s->is_metadata) { |
| 1680 | return; |
| 1681 | } |
| 1682 | |
| 1683 | if (!s->ringbuffer) { |
| 1684 | output_size = 0; |
| 1685 | } else { |
| 1686 | output_size = s->pos; |
| 1687 | } |
| 1688 | output_size += s->meta_block_remaining_len; |
| 1689 | min_size = min_size < output_size ? output_size : min_size; |
| 1690 | |
| 1691 | if (!!s->canny_ringbuffer_allocation) { |
| 1692 | /* Reduce ring buffer size to save memory when server is unscrupulous. |
| 1693 | In worst case memory usage might be 1.5x bigger for a short period of |
| 1694 | ring buffer reallocation. */ |
| 1695 | while ((new_ringbuffer_size >> 1) >= min_size) { |
| 1696 | new_ringbuffer_size >>= 1; |
| 1697 | } |
| 1698 | } |
| 1699 | |
| 1700 | s->new_ringbuffer_size = new_ringbuffer_size; |
| 1701 | } |
| 1702 | |
| 1703 | /* Reads 1..256 2-bit context modes. */ |
| 1704 | static BrotliDecoderErrorCode ReadContextModes(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1705 | BrotliBitReader* br = &s->br; |
| 1706 | int i = s->loop_counter; |
| 1707 | |
| 1708 | while (i < (int)s->num_block_types[0]) { |
| 1709 | brotli_reg_tuint64_t bits; |
| 1710 | if (!BrotliSafeReadBits(br, 2, &bits)) { |
| 1711 | s->loop_counter = i; |
| 1712 | return BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 1713 | } |
| 1714 | s->context_modes[i] = (uint8_t)bits; |
| 1715 | BROTLI_LOG_ARRAY_INDEX(s->context_modes, i); |
| 1716 | i++; |
| 1717 | } |
| 1718 | return BROTLI_DECODER_SUCCESS; |
| 1719 | } |
| 1720 | |
| 1721 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void TakeDistanceFromRingBuffer(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1722 | int offset = s->distance_code - 3; |
| 1723 | if (s->distance_code <= 3) { |
| 1724 | /* Compensate double distance-ring-buffer roll for dictionary items. */ |
| 1725 | s->distance_context = 1 >> s->distance_code; |
| 1726 | s->distance_code = s->dist_rb[(s->dist_rb_idx - offset) & 3]; |
| 1727 | s->dist_rb_idx -= s->distance_context; |
| 1728 | } else { |
| 1729 | int index_delta = 3; |
| 1730 | int delta; |
| 1731 | int base = s->distance_code - 10; |
| 1732 | if (s->distance_code < 10) { |
| 1733 | base = s->distance_code - 4; |
| 1734 | } else { |
| 1735 | index_delta = 2; |
| 1736 | } |
| 1737 | /* Unpack one of six 4-bit values. */ |
| 1738 | delta = ((0x605142 >> (4 * base)) & 0xF) - 3; |
| 1739 | s->distance_code = s->dist_rb[(s->dist_rb_idx + index_delta) & 0x3] + delta; |
| 1740 | if (s->distance_code <= 0) { |
| 1741 | /* A huge distance will cause a BROTLI_FAILURE() soon. |
| 1742 | This is a little faster than failing here. */ |
| 1743 | s->distance_code = 0x7FFFFFFF; |
| 1744 | } |
| 1745 | } |
| 1746 | } |
| 1747 | |
| 1748 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadBits( |
| 1749 | BrotliBitReader* const br, brotli_reg_tuint64_t n_bits, brotli_reg_tuint64_t* val) { |
| 1750 | if (n_bits != 0) { |
| 1751 | return BrotliSafeReadBits(br, n_bits, val); |
| 1752 | } else { |
| 1753 | *val = 0; |
| 1754 | return BROTLI_TRUE1; |
| 1755 | } |
| 1756 | } |
| 1757 | |
| 1758 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadBits32( |
| 1759 | BrotliBitReader* const br, brotli_reg_tuint64_t n_bits, brotli_reg_tuint64_t* val) { |
| 1760 | if (n_bits != 0) { |
| 1761 | return BrotliSafeReadBits32(br, n_bits, val); |
| 1762 | } else { |
| 1763 | *val = 0; |
| 1764 | return BROTLI_TRUE1; |
| 1765 | } |
| 1766 | } |
| 1767 | |
| 1768 | /* |
| 1769 | RFC 7932 Section 4 with "..." shortenings and "[]" emendations. |
| 1770 | |
| 1771 | Each distance ... is represented with a pair <distance code, extra bits>... |
| 1772 | The distance code is encoded using a prefix code... The number of extra bits |
| 1773 | can be 0..24... Two additional parameters: NPOSTFIX (0..3), and ... |
| 1774 | NDIRECT (0..120) ... are encoded in the meta-block header... |
| 1775 | |
| 1776 | The first 16 distance symbols ... reference past distances... ring buffer ... |
| 1777 | Next NDIRECT distance symbols ... represent distances from 1 to NDIRECT... |
| 1778 | [For] distance symbols 16 + NDIRECT and greater ... the number of extra bits |
| 1779 | ... is given by the following formula: |
| 1780 | |
| 1781 | [ xcode = dcode - NDIRECT - 16 ] |
| 1782 | ndistbits = 1 + [ xcode ] >> (NPOSTFIX + 1) |
| 1783 | |
| 1784 | ... |
| 1785 | */ |
| 1786 | |
| 1787 | /* |
| 1788 | RFC 7932 Section 9.2 with "..." shortenings and "[]" emendations. |
| 1789 | |
| 1790 | ... to get the actual value of the parameter NDIRECT, left-shift this |
| 1791 | four-bit number by NPOSTFIX bits ... |
| 1792 | */ |
| 1793 | |
| 1794 | /* Remaining formulas from RFC 7932 Section 4 could be rewritten as following: |
| 1795 | |
| 1796 | alphabet_size = 16 + NDIRECT + (max_distbits << (NPOSTFIX + 1)) |
| 1797 | |
| 1798 | half = ((xcode >> NPOSTFIX) & 1) << ndistbits |
| 1799 | postfix = xcode & ((1 << NPOSTFIX) - 1) |
| 1800 | range_start = 2 * (1 << ndistbits - 1 - 1) |
| 1801 | |
| 1802 | distance = (range_start + half + extra) << NPOSTFIX + postfix + NDIRECT + 1 |
| 1803 | |
| 1804 | NB: ndistbits >= 1 -> range_start >= 0 |
| 1805 | NB: range_start has factor 2, as the range is covered by 2 "halves" |
| 1806 | NB: extra -1 offset in range_start formula covers the absence of |
| 1807 | ndistbits = 0 case |
| 1808 | NB: when NPOSTFIX = 0, NDIRECT is not greater than 15 |
| 1809 | |
| 1810 | In other words, xcode has the following binary structure - XXXHPPP: |
| 1811 | - XXX represent the number of extra distance bits |
| 1812 | - H selects upper / lower range of distances |
| 1813 | - PPP represent "postfix" |
| 1814 | |
| 1815 | "Regular" distance encoding has NPOSTFIX = 0; omitting the postfix part |
| 1816 | simplifies distance calculation. |
| 1817 | |
| 1818 | Using NPOSTFIX > 0 allows cheaper encoding of regular structures, e.g. where |
| 1819 | most of distances have the same reminder of division by 2/4/8. For example, |
| 1820 | the table of int32_t values that come from different sources; if it is likely |
| 1821 | that 3 highest bytes of values from the same source are the same, then |
| 1822 | copy distance often looks like 4x + y. |
| 1823 | |
| 1824 | Distance calculation could be rewritten to: |
| 1825 | |
| 1826 | ndistbits = NDISTBITS(NDIRECT, NPOSTFIX)[dcode] |
| 1827 | distance = OFFSET(NDIRECT, NPOSTFIX)[dcode] + extra << NPOSTFIX |
| 1828 | |
| 1829 | NDISTBITS and OFFSET could be pre-calculated, as NDIRECT and NPOSTFIX could |
| 1830 | change only once per meta-block. |
| 1831 | */ |
| 1832 | |
| 1833 | /* Calculates distance lookup table. |
| 1834 | NB: it is possible to have all 64 tables precalculated. */ |
| 1835 | static void CalculateDistanceLut(BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 1836 | BrotliMetablockBodyArena* b = &s->arena.body; |
| 1837 | brotli_reg_tuint64_t npostfix = s->distance_postfix_bits; |
| 1838 | brotli_reg_tuint64_t ndirect = s->num_direct_distance_codes; |
| 1839 | brotli_reg_tuint64_t alphabet_size_limit = s->distance_hgroup.alphabet_size_limit; |
| 1840 | brotli_reg_tuint64_t postfix = (brotli_reg_tuint64_t)1u << npostfix; |
| 1841 | brotli_reg_tuint64_t j; |
| 1842 | brotli_reg_tuint64_t bits = 1; |
| 1843 | brotli_reg_tuint64_t half = 0; |
| 1844 | |
| 1845 | /* Skip short codes. */ |
| 1846 | brotli_reg_tuint64_t i = BROTLI_NUM_DISTANCE_SHORT_CODES16; |
| 1847 | |
| 1848 | /* Fill direct codes. */ |
| 1849 | for (j = 0; j < ndirect; ++j) { |
| 1850 | b->dist_extra_bits[i] = 0; |
| 1851 | b->dist_offset[i] = j + 1; |
| 1852 | ++i; |
| 1853 | } |
| 1854 | |
| 1855 | /* Fill regular distance codes. */ |
| 1856 | while (i < alphabet_size_limit) { |
| 1857 | brotli_reg_tuint64_t base = ndirect + ((((2 + half) << bits) - 4) << npostfix) + 1; |
| 1858 | /* Always fill the complete group. */ |
| 1859 | for (j = 0; j < postfix; ++j) { |
| 1860 | b->dist_extra_bits[i] = (uint8_t)bits; |
| 1861 | b->dist_offset[i] = base + j; |
| 1862 | ++i; |
| 1863 | } |
| 1864 | bits = bits + half; |
| 1865 | half = half ^ 1; |
| 1866 | } |
| 1867 | } |
| 1868 | |
| 1869 | /* Precondition: s->distance_code < 0. */ |
| 1870 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint ReadDistanceInternal( |
| 1871 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br) { |
| 1872 | BrotliMetablockBodyArena* b = &s->arena.body; |
| 1873 | brotli_reg_tuint64_t code; |
| 1874 | brotli_reg_tuint64_t bits; |
| 1875 | BrotliBitReaderState memento; |
| 1876 | HuffmanCode* distance_tree = s->distance_hgroup.htrees[s->dist_htree_index]; |
| 1877 | if (!safe) { |
| 1878 | code = ReadSymbol(distance_tree, br); |
| 1879 | } else { |
| 1880 | BrotliBitReaderSaveState(br, &memento); |
| 1881 | if (!SafeReadSymbol(distance_tree, br, &code)) { |
| 1882 | return BROTLI_FALSE0; |
| 1883 | } |
| 1884 | } |
| 1885 | --s->block_length[2]; |
| 1886 | /* Convert the distance code to the actual distance by possibly |
| 1887 | looking up past distances from the s->dist_rb. */ |
| 1888 | s->distance_context = 0; |
| 1889 | if ((code & ~0xFu) == 0) { |
| 1890 | s->distance_code = (int)code; |
| 1891 | TakeDistanceFromRingBuffer(s); |
| 1892 | return BROTLI_TRUE1; |
| 1893 | } |
| 1894 | if (!safe) { |
| 1895 | bits = BrotliReadBits32(br, b->dist_extra_bits[code]); |
| 1896 | } else { |
| 1897 | if (!SafeReadBits32(br, b->dist_extra_bits[code], &bits)) { |
| 1898 | ++s->block_length[2]; |
| 1899 | BrotliBitReaderRestoreState(br, &memento); |
| 1900 | return BROTLI_FALSE0; |
| 1901 | } |
| 1902 | } |
| 1903 | s->distance_code = |
| 1904 | (int)(b->dist_offset[code] + (bits << s->distance_postfix_bits)); |
| 1905 | return BROTLI_TRUE1; |
| 1906 | } |
| 1907 | |
| 1908 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void ReadDistance( |
| 1909 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br) { |
| 1910 | ReadDistanceInternal(0, s, br); |
| 1911 | } |
| 1912 | |
| 1913 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadDistance( |
| 1914 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br) { |
| 1915 | return ReadDistanceInternal(1, s, br); |
| 1916 | } |
| 1917 | |
| 1918 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint ReadCommandInternal( |
| 1919 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br, int* insert_length) { |
| 1920 | brotli_reg_tuint64_t cmd_code; |
| 1921 | brotli_reg_tuint64_t insert_len_extra = 0; |
| 1922 | brotli_reg_tuint64_t copy_length; |
| 1923 | CmdLutElement v; |
| 1924 | BrotliBitReaderState memento; |
| 1925 | if (!safe) { |
| 1926 | cmd_code = ReadSymbol(s->htree_command, br); |
| 1927 | } else { |
| 1928 | BrotliBitReaderSaveState(br, &memento); |
| 1929 | if (!SafeReadSymbol(s->htree_command, br, &cmd_code)) { |
| 1930 | return BROTLI_FALSE0; |
| 1931 | } |
| 1932 | } |
| 1933 | v = kCmdLut[cmd_code]; |
| 1934 | s->distance_code = v.distance_code; |
| 1935 | s->distance_context = v.context; |
| 1936 | s->dist_htree_index = s->dist_context_map_slice[s->distance_context]; |
| 1937 | *insert_length = v.insert_len_offset; |
| 1938 | if (!safe) { |
| 1939 | if (BROTLI_PREDICT_FALSE(v.insert_len_extra_bits != 0)(__builtin_expect(v.insert_len_extra_bits != 0, 0))) { |
| 1940 | insert_len_extra = BrotliReadBits24(br, v.insert_len_extra_bits); |
| 1941 | } |
| 1942 | copy_length = BrotliReadBits24(br, v.copy_len_extra_bits); |
| 1943 | } else { |
| 1944 | if (!SafeReadBits(br, v.insert_len_extra_bits, &insert_len_extra) || |
| 1945 | !SafeReadBits(br, v.copy_len_extra_bits, ©_length)) { |
| 1946 | BrotliBitReaderRestoreState(br, &memento); |
| 1947 | return BROTLI_FALSE0; |
| 1948 | } |
| 1949 | } |
| 1950 | s->copy_length = (int)copy_length + v.copy_len_offset; |
| 1951 | --s->block_length[1]; |
| 1952 | *insert_length += (int)insert_len_extra; |
| 1953 | return BROTLI_TRUE1; |
| 1954 | } |
| 1955 | |
| 1956 | static BROTLI_INLINEinline __attribute__((__always_inline__)) void ReadCommand( |
| 1957 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br, int* insert_length) { |
| 1958 | ReadCommandInternal(0, s, br, insert_length); |
| 1959 | } |
| 1960 | |
| 1961 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint SafeReadCommand( |
| 1962 | BrotliDecoderStateBrotliDecoderStateInternal* s, BrotliBitReader* br, int* insert_length) { |
| 1963 | return ReadCommandInternal(1, s, br, insert_length); |
| 1964 | } |
| 1965 | |
| 1966 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BROTLI_BOOLint CheckInputAmount( |
| 1967 | int safe, BrotliBitReader* const br) { |
| 1968 | if (safe) { |
| 1969 | return BROTLI_TRUE1; |
| 1970 | } |
| 1971 | return BrotliCheckInputAmount(br); |
| 1972 | } |
| 1973 | |
| 1974 | /* NB: METHOD should return BROTLI_FALSE only in case there is not enough input; |
| 1975 | in case of "unsafe" execution, when input is guaranteed to be sufficient, |
| 1976 | result is ignored. */ |
| 1977 | #define BROTLI_SAFE(METHOD) \ |
| 1978 | { \ |
| 1979 | if (safe) { \ |
| 1980 | if (!Safe##METHOD) { \ |
| 1981 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; \ |
| 1982 | goto saveStateAndReturn; \ |
| 1983 | } \ |
| 1984 | } else { \ |
| 1985 | METHOD; \ |
| 1986 | } \ |
| 1987 | } |
| 1988 | |
| 1989 | /* NB: METHOD should return BROTLI_DECODER_SUCCESS, BROTLI_DECODER_ERROR_*, or |
| 1990 | BROTLI_DECODER_NEEDS_MORE_INPUT; the later two break the processing. */ |
| 1991 | #define BROTLI_SAFE_WITH_STATUS(METHOD){ BrotliDecoderErrorCode status; if (safe) { status = SafeMETHOD ; } else { status = METHOD; } if (status != BROTLI_DECODER_SUCCESS ) { result = status; goto saveStateAndReturn; } } \ |
| 1992 | { \ |
| 1993 | BrotliDecoderErrorCode status; \ |
| 1994 | if (safe) { \ |
| 1995 | status = Safe##METHOD; \ |
| 1996 | } else { \ |
| 1997 | status = METHOD; \ |
| 1998 | } \ |
| 1999 | if (status != BROTLI_DECODER_SUCCESS) { \ |
| 2000 | result = status; \ |
| 2001 | goto saveStateAndReturn; \ |
| 2002 | } \ |
| 2003 | } |
| 2004 | |
| 2005 | static BROTLI_INLINEinline __attribute__((__always_inline__)) BrotliDecoderErrorCode ProcessCommandsInternal( |
| 2006 | int safe, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2007 | int pos = s->pos; |
| 2008 | int i = s->loop_counter; |
| 2009 | BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; |
| 2010 | BrotliBitReader* br = &s->br; |
| 2011 | uint32_t compound_dictionary_size = GetCompoundDictionarySize(s); |
| 2012 | |
| 2013 | if (!CheckInputAmount(safe, br)) { |
| 2014 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2015 | goto saveStateAndReturn; |
| 2016 | } |
| 2017 | if (!safe) { |
| 2018 | BROTLI_UNUSED(BrotliWarmupBitReader(br))(void)(BrotliWarmupBitReader(br)); |
| 2019 | } |
| 2020 | |
| 2021 | /* Jump into state machine. */ |
| 2022 | if (s->state == BROTLI_STATE_COMMAND_BEGIN) { |
| 2023 | goto CommandBegin; |
| 2024 | } else if (s->state == BROTLI_STATE_COMMAND_INNER) { |
| 2025 | goto CommandInner; |
| 2026 | } else if (s->state == BROTLI_STATE_COMMAND_POST_DECODE_LITERALS) { |
| 2027 | goto CommandPostDecodeLiterals; |
| 2028 | } else if (s->state == BROTLI_STATE_COMMAND_POST_WRAP_COPY) { |
| 2029 | goto CommandPostWrapCopy; |
| 2030 | } else { |
| 2031 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE); /* COV_NF_LINE */ |
| 2032 | } |
| 2033 | |
| 2034 | CommandBegin: |
| 2035 | if (safe) { |
| 2036 | s->state = BROTLI_STATE_COMMAND_BEGIN; |
| 2037 | } |
| 2038 | if (!CheckInputAmount(safe, br)) { |
| 2039 | s->state = BROTLI_STATE_COMMAND_BEGIN; |
| 2040 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2041 | goto saveStateAndReturn; |
| 2042 | } |
| 2043 | if (BROTLI_PREDICT_FALSE(s->block_length[1] == 0)(__builtin_expect(s->block_length[1] == 0, 0))) { |
| 2044 | BROTLI_SAFE_WITH_STATUS(DecodeCommandBlockSwitch(s)){ BrotliDecoderErrorCode status; if (safe) { status = SafeDecodeCommandBlockSwitch (s); } else { status = DecodeCommandBlockSwitch(s); } if (status != BROTLI_DECODER_SUCCESS) { result = status; goto saveStateAndReturn ; } }; |
| 2045 | goto CommandBegin; |
| 2046 | } |
| 2047 | /* Read the insert/copy length in the command. */ |
| 2048 | BROTLI_SAFE(ReadCommand(s, br, &i)); |
| 2049 | BROTLI_LOG(("[ProcessCommandsInternal] pos = %d insert = %d copy = %d\n", |
| 2050 | pos, i, s->copy_length)); |
| 2051 | if (i == 0) { |
| 2052 | goto CommandPostDecodeLiterals; |
| 2053 | } |
| 2054 | s->meta_block_remaining_len -= i; |
| 2055 | |
| 2056 | CommandInner: |
| 2057 | if (safe) { |
| 2058 | s->state = BROTLI_STATE_COMMAND_INNER; |
| 2059 | } |
| 2060 | /* Read the literals in the command. */ |
| 2061 | if (s->trivial_literal_context) { |
| 2062 | brotli_reg_tuint64_t bits; |
| 2063 | brotli_reg_tuint64_t value; |
| 2064 | PreloadSymbol(safe, s->literal_htree, br, &bits, &value); |
| 2065 | if (!safe) { |
| 2066 | // This is a hottest part of the decode, so we copy the loop below |
| 2067 | // and optimize it by calculating the number of steps where all checks |
| 2068 | // evaluate to false (ringbuffer size/block size/input size). |
| 2069 | // Since all checks are loop invariant, we just need to find |
| 2070 | // minimal number of iterations for a simple loop, and run |
| 2071 | // the full version for the remainder. |
| 2072 | int num_steps = i - 1; |
| 2073 | if (num_steps > 0 && ((brotli_reg_tuint64_t)(num_steps) > s->block_length[0])) { |
| 2074 | // Safe cast, since block_length < steps |
| 2075 | num_steps = (int)s->block_length[0]; |
| 2076 | } |
| 2077 | if (s->ringbuffer_size >= pos && |
| 2078 | (s->ringbuffer_size - pos) <= num_steps) { |
| 2079 | num_steps = s->ringbuffer_size - pos - 1; |
| 2080 | } |
| 2081 | if (num_steps < 0) { |
| 2082 | num_steps = 0; |
| 2083 | } |
| 2084 | num_steps = BrotliCopyPreloadedSymbolsToU8(s->literal_htree, br, &bits, |
| 2085 | &value, s->ringbuffer, pos, |
| 2086 | num_steps); |
| 2087 | pos += num_steps; |
| 2088 | s->block_length[0] -= (brotli_reg_tuint64_t)num_steps; |
| 2089 | i -= num_steps; |
| 2090 | do { |
| 2091 | if (!CheckInputAmount(safe, br)) { |
| 2092 | s->state = BROTLI_STATE_COMMAND_INNER; |
| 2093 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2094 | goto saveStateAndReturn; |
| 2095 | } |
| 2096 | if (BROTLI_PREDICT_FALSE(s->block_length[0] == 0)(__builtin_expect(s->block_length[0] == 0, 0))) { |
| 2097 | goto NextLiteralBlock; |
| 2098 | } |
| 2099 | BrotliCopyPreloadedSymbolsToU8(s->literal_htree, br, &bits, &value, |
| 2100 | s->ringbuffer, pos, 1); |
| 2101 | --s->block_length[0]; |
| 2102 | BROTLI_LOG_ARRAY_INDEX(s->ringbuffer, pos); |
| 2103 | ++pos; |
| 2104 | if (BROTLI_PREDICT_FALSE(pos == s->ringbuffer_size)(__builtin_expect(pos == s->ringbuffer_size, 0))) { |
| 2105 | s->state = BROTLI_STATE_COMMAND_INNER_WRITE; |
| 2106 | --i; |
| 2107 | goto saveStateAndReturn; |
| 2108 | } |
| 2109 | } while (--i != 0); |
| 2110 | } else { /* safe */ |
| 2111 | do { |
| 2112 | brotli_reg_tuint64_t literal; |
| 2113 | if (BROTLI_PREDICT_FALSE(s->block_length[0] == 0)(__builtin_expect(s->block_length[0] == 0, 0))) { |
| 2114 | goto NextLiteralBlock; |
| 2115 | } |
| 2116 | if (!SafeReadSymbol(s->literal_htree, br, &literal)) { |
| 2117 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2118 | goto saveStateAndReturn; |
| 2119 | } |
| 2120 | s->ringbuffer[pos] = (uint8_t)literal; |
| 2121 | --s->block_length[0]; |
| 2122 | BROTLI_LOG_ARRAY_INDEX(s->ringbuffer, pos); |
| 2123 | ++pos; |
| 2124 | if (BROTLI_PREDICT_FALSE(pos == s->ringbuffer_size)(__builtin_expect(pos == s->ringbuffer_size, 0))) { |
| 2125 | s->state = BROTLI_STATE_COMMAND_INNER_WRITE; |
| 2126 | --i; |
| 2127 | goto saveStateAndReturn; |
| 2128 | } |
| 2129 | } while (--i != 0); |
| 2130 | } |
| 2131 | } else { |
| 2132 | uint8_t p1 = s->ringbuffer[(pos - 1) & s->ringbuffer_mask]; |
| 2133 | uint8_t p2 = s->ringbuffer[(pos - 2) & s->ringbuffer_mask]; |
| 2134 | do { |
| 2135 | const HuffmanCode* hc; |
| 2136 | uint8_t context; |
| 2137 | if (!CheckInputAmount(safe, br)) { |
| 2138 | s->state = BROTLI_STATE_COMMAND_INNER; |
| 2139 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2140 | goto saveStateAndReturn; |
| 2141 | } |
| 2142 | if (BROTLI_PREDICT_FALSE(s->block_length[0] == 0)(__builtin_expect(s->block_length[0] == 0, 0))) { |
| 2143 | goto NextLiteralBlock; |
| 2144 | } |
| 2145 | context = BROTLI_CONTEXT(p1, p2, s->context_lookup)((s->context_lookup)[p1] | ((s->context_lookup) + 256)[ p2]); |
| 2146 | BROTLI_LOG_UINT(context); |
| 2147 | hc = s->literal_hgroup.htrees[s->context_map_slice[context]]; |
| 2148 | p2 = p1; |
| 2149 | if (!safe) { |
| 2150 | p1 = (uint8_t)ReadSymbol(hc, br); |
| 2151 | } else { |
| 2152 | brotli_reg_tuint64_t literal; |
| 2153 | if (!SafeReadSymbol(hc, br, &literal)) { |
| 2154 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2155 | goto saveStateAndReturn; |
| 2156 | } |
| 2157 | p1 = (uint8_t)literal; |
| 2158 | } |
| 2159 | s->ringbuffer[pos] = p1; |
| 2160 | --s->block_length[0]; |
| 2161 | BROTLI_LOG_UINT(s->context_map_slice[context]); |
| 2162 | BROTLI_LOG_ARRAY_INDEX(s->ringbuffer, pos & s->ringbuffer_mask); |
| 2163 | ++pos; |
| 2164 | if (BROTLI_PREDICT_FALSE(pos == s->ringbuffer_size)(__builtin_expect(pos == s->ringbuffer_size, 0))) { |
| 2165 | s->state = BROTLI_STATE_COMMAND_INNER_WRITE; |
| 2166 | --i; |
| 2167 | goto saveStateAndReturn; |
| 2168 | } |
| 2169 | } while (--i != 0); |
| 2170 | } |
| 2171 | BROTLI_LOG_UINT(s->meta_block_remaining_len); |
| 2172 | if (BROTLI_PREDICT_FALSE(s->meta_block_remaining_len <= 0)(__builtin_expect(s->meta_block_remaining_len <= 0, 0))) { |
| 2173 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2174 | goto saveStateAndReturn; |
| 2175 | } |
| 2176 | |
| 2177 | CommandPostDecodeLiterals: |
| 2178 | if (safe) { |
| 2179 | s->state = BROTLI_STATE_COMMAND_POST_DECODE_LITERALS; |
| 2180 | } |
| 2181 | if (s->distance_code >= 0) { |
| 2182 | /* Implicit distance case. */ |
| 2183 | s->distance_context = s->distance_code ? 0 : 1; |
| 2184 | --s->dist_rb_idx; |
| 2185 | s->distance_code = s->dist_rb[s->dist_rb_idx & 3]; |
| 2186 | } else { |
| 2187 | /* Read distance code in the command, unless it was implicitly zero. */ |
| 2188 | if (BROTLI_PREDICT_FALSE(s->block_length[2] == 0)(__builtin_expect(s->block_length[2] == 0, 0))) { |
| 2189 | BROTLI_SAFE_WITH_STATUS(DecodeDistanceBlockSwitch(s)){ BrotliDecoderErrorCode status; if (safe) { status = SafeDecodeDistanceBlockSwitch (s); } else { status = DecodeDistanceBlockSwitch(s); } if (status != BROTLI_DECODER_SUCCESS) { result = status; goto saveStateAndReturn ; } }; |
| 2190 | } |
| 2191 | BROTLI_SAFE(ReadDistance(s, br)); |
| 2192 | } |
| 2193 | BROTLI_LOG(("[ProcessCommandsInternal] pos = %d distance = %d\n", |
| 2194 | pos, s->distance_code)); |
| 2195 | if (s->max_distance != s->max_backward_distance) { |
| 2196 | s->max_distance = |
| 2197 | (pos < s->max_backward_distance) ? pos : s->max_backward_distance; |
| 2198 | } |
| 2199 | i = s->copy_length; |
| 2200 | /* Apply copy of LZ77 back-reference, or static dictionary reference if |
| 2201 | the distance is larger than the max LZ77 distance */ |
| 2202 | if (s->distance_code > s->max_distance) { |
| 2203 | /* The maximum allowed distance is BROTLI_MAX_ALLOWED_DISTANCE = 0x7FFFFFFC. |
| 2204 | With this choice, no signed overflow can occur after decoding |
| 2205 | a special distance code (e.g., after adding 3 to the last distance). */ |
| 2206 | if (s->distance_code > BROTLI_MAX_ALLOWED_DISTANCE0x7FFFFFFC) { |
| 2207 | BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " |
| 2208 | "len: %d bytes left: %d\n", |
| 2209 | pos, s->distance_code, i, s->meta_block_remaining_len)); |
| 2210 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_DISTANCE)((void)(0), BROTLI_DECODER_ERROR_FORMAT_DISTANCE); |
| 2211 | } |
| 2212 | /* Check that LZ77-dictionary address is non-negative. */ |
| 2213 | if ((uint32_t)(s->distance_code - s->max_distance) - 1u < |
| 2214 | compound_dictionary_size) { |
| 2215 | /* Given that `s->distance_code - s->max_distance > 0` we have `address` |
| 2216 | * is strictly less than `compound_dictionary_size`. */ |
| 2217 | uint32_t address = compound_dictionary_size - |
| 2218 | (uint32_t)(s->distance_code - s->max_distance); |
| 2219 | if (!InitializeCompoundDictionaryCopy(s, address, (uint32_t)i)) { |
| 2220 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_COMPOUND_DICTIONARY)((void)(0), BROTLI_DECODER_ERROR_COMPOUND_DICTIONARY); |
| 2221 | } |
| 2222 | pos += CopyFromCompoundDictionary(s, pos); |
| 2223 | if (pos >= s->ringbuffer_size) { |
| 2224 | s->state = BROTLI_STATE_COMMAND_POST_WRITE_1; |
| 2225 | goto saveStateAndReturn; |
| 2226 | } |
| 2227 | /* In else branch we have: |
| 2228 | * `s->distance_code - s->max_distance - 1 >= compound_dictionary_size`; |
| 2229 | * that implies that `compound_dictionary_size` could be cast to int. */ |
| 2230 | } else if (i >= SHARED_BROTLI_MIN_DICTIONARY_WORD_LENGTH4 && |
| 2231 | i <= SHARED_BROTLI_MAX_DICTIONARY_WORD_LENGTH31) { |
| 2232 | uint8_t p1 = s->ringbuffer[(pos - 1) & s->ringbuffer_mask]; |
| 2233 | uint8_t p2 = s->ringbuffer[(pos - 2) & s->ringbuffer_mask]; |
| 2234 | uint8_t dict_id = s->dictionary->context_based ? |
| 2235 | s->dictionary->context_map[BROTLI_CONTEXT(p1, p2, s->context_lookup)((s->context_lookup)[p1] | ((s->context_lookup) + 256)[ p2])] |
| 2236 | : 0; |
| 2237 | const BrotliDictionary* words = s->dictionary->words[dict_id]; |
| 2238 | const BrotliTransforms* transforms = s->dictionary->transforms[dict_id]; |
| 2239 | int offset = (int)words->offsets_by_length[i]; |
| 2240 | brotli_reg_tuint64_t shift = words->size_bits_by_length[i]; |
| 2241 | int address = s->distance_code - s->max_distance - 1 - |
| 2242 | (int)compound_dictionary_size; |
| 2243 | int mask = (int)BitMask(shift); |
| 2244 | int word_idx = address & mask; |
| 2245 | int transform_idx = address >> shift; |
| 2246 | /* Compensate double distance-ring-buffer roll. */ |
| 2247 | s->dist_rb_idx += s->distance_context; |
| 2248 | offset += word_idx * i; |
| 2249 | /* If the distance is out of bound, select a next static dictionary if |
| 2250 | there exist multiple. */ |
| 2251 | if ((transform_idx >= (int)transforms->num_transforms || |
| 2252 | words->size_bits_by_length[i] == 0) && |
| 2253 | s->dictionary->num_dictionaries > 1) { |
| 2254 | uint8_t dict_id2; |
| 2255 | int dist_remaining = address - |
| 2256 | (int)(((1u << shift) & ~1u)) * (int)transforms->num_transforms; |
| 2257 | for (dict_id2 = 0; dict_id2 < s->dictionary->num_dictionaries; |
| 2258 | dict_id2++) { |
| 2259 | const BrotliDictionary* words2 = s->dictionary->words[dict_id2]; |
| 2260 | if (dict_id2 != dict_id && words2->size_bits_by_length[i] != 0) { |
| 2261 | const BrotliTransforms* transforms2 = |
| 2262 | s->dictionary->transforms[dict_id2]; |
| 2263 | brotli_reg_tuint64_t shift2 = words2->size_bits_by_length[i]; |
| 2264 | int num = (int)((1u << shift2) & ~1u) * |
| 2265 | (int)transforms2->num_transforms; |
| 2266 | if (dist_remaining < num) { |
| 2267 | dict_id = dict_id2; |
Value stored to 'dict_id' is never read | |
| 2268 | words = words2; |
| 2269 | transforms = transforms2; |
| 2270 | address = dist_remaining; |
| 2271 | shift = shift2; |
| 2272 | mask = (int)BitMask(shift); |
| 2273 | word_idx = address & mask; |
| 2274 | transform_idx = address >> shift; |
| 2275 | offset = (int)words->offsets_by_length[i] + word_idx * i; |
| 2276 | break; |
| 2277 | } |
| 2278 | dist_remaining -= num; |
| 2279 | } |
| 2280 | } |
| 2281 | } |
| 2282 | if (BROTLI_PREDICT_FALSE(words->size_bits_by_length[i] == 0)(__builtin_expect(words->size_bits_by_length[i] == 0, 0))) { |
| 2283 | BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " |
| 2284 | "len: %d bytes left: %d\n", |
| 2285 | pos, s->distance_code, i, s->meta_block_remaining_len)); |
| 2286 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_DICTIONARY)((void)(0), BROTLI_DECODER_ERROR_FORMAT_DICTIONARY); |
| 2287 | } |
| 2288 | if (BROTLI_PREDICT_FALSE(!words->data)(__builtin_expect(!words->data, 0))) { |
| 2289 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_DICTIONARY_NOT_SET)((void)(0), BROTLI_DECODER_ERROR_DICTIONARY_NOT_SET); |
| 2290 | } |
| 2291 | if (transform_idx < (int)transforms->num_transforms) { |
| 2292 | const uint8_t* word = &words->data[offset]; |
| 2293 | int len = i; |
| 2294 | if (transform_idx == transforms->cutOffTransforms[0]) { |
| 2295 | memcpy(&s->ringbuffer[pos], word, (size_t)len); |
| 2296 | BROTLI_LOG(("[ProcessCommandsInternal] dictionary word: [%.*s]\n", |
| 2297 | len, word)); |
| 2298 | } else { |
| 2299 | len = BrotliTransformDictionaryWord(&s->ringbuffer[pos], word, len, |
| 2300 | transforms, transform_idx); |
| 2301 | BROTLI_LOG(("[ProcessCommandsInternal] dictionary word: [%.*s]," |
| 2302 | " transform_idx = %d, transformed: [%.*s]\n", |
| 2303 | i, word, transform_idx, len, &s->ringbuffer[pos])); |
| 2304 | if (len == 0 && s->distance_code <= 120) { |
| 2305 | BROTLI_LOG(("Invalid length-0 dictionary word after transform\n")); |
| 2306 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_TRANSFORM)((void)(0), BROTLI_DECODER_ERROR_FORMAT_TRANSFORM); |
| 2307 | } |
| 2308 | } |
| 2309 | pos += len; |
| 2310 | s->meta_block_remaining_len -= len; |
| 2311 | if (pos >= s->ringbuffer_size) { |
| 2312 | s->state = BROTLI_STATE_COMMAND_POST_WRITE_1; |
| 2313 | goto saveStateAndReturn; |
| 2314 | } |
| 2315 | } else { |
| 2316 | BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " |
| 2317 | "len: %d bytes left: %d\n", |
| 2318 | pos, s->distance_code, i, s->meta_block_remaining_len)); |
| 2319 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_TRANSFORM)((void)(0), BROTLI_DECODER_ERROR_FORMAT_TRANSFORM); |
| 2320 | } |
| 2321 | } else { |
| 2322 | BROTLI_LOG(("Invalid backward reference. pos: %d distance: %d " |
| 2323 | "len: %d bytes left: %d\n", |
| 2324 | pos, s->distance_code, i, s->meta_block_remaining_len)); |
| 2325 | return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_DICTIONARY)((void)(0), BROTLI_DECODER_ERROR_FORMAT_DICTIONARY); |
| 2326 | } |
| 2327 | } else { |
| 2328 | int src_start = (pos - s->distance_code) & s->ringbuffer_mask; |
| 2329 | uint8_t* copy_dst = &s->ringbuffer[pos]; |
| 2330 | uint8_t* copy_src = &s->ringbuffer[src_start]; |
| 2331 | int dst_end = pos + i; |
| 2332 | int src_end = src_start + i; |
| 2333 | /* Update the recent distances cache. */ |
| 2334 | s->dist_rb[s->dist_rb_idx & 3] = s->distance_code; |
| 2335 | ++s->dist_rb_idx; |
| 2336 | s->meta_block_remaining_len -= i; |
| 2337 | /* There are 32+ bytes of slack in the ring-buffer allocation. |
| 2338 | Also, we have 16 short codes, that make these 16 bytes irrelevant |
| 2339 | in the ring-buffer. Let's copy over them as a first guess. */ |
| 2340 | memmove16(copy_dst, copy_src); |
| 2341 | if (src_end > pos && dst_end > src_start) { |
| 2342 | /* Regions intersect. */ |
| 2343 | goto CommandPostWrapCopy; |
| 2344 | } |
| 2345 | if (dst_end >= s->ringbuffer_size || src_end >= s->ringbuffer_size) { |
| 2346 | /* At least one region wraps. */ |
| 2347 | goto CommandPostWrapCopy; |
| 2348 | } |
| 2349 | pos += i; |
| 2350 | if (i > 16) { |
| 2351 | if (i > 32) { |
| 2352 | memcpy(copy_dst + 16, copy_src + 16, (size_t)(i - 16)); |
| 2353 | } else { |
| 2354 | /* This branch covers about 45% cases. |
| 2355 | Fixed size short copy allows more compiler optimizations. */ |
| 2356 | memmove16(copy_dst + 16, copy_src + 16); |
| 2357 | } |
| 2358 | } |
| 2359 | } |
| 2360 | BROTLI_LOG_UINT(s->meta_block_remaining_len); |
| 2361 | if (s->meta_block_remaining_len <= 0) { |
| 2362 | /* Next metablock, if any. */ |
| 2363 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2364 | goto saveStateAndReturn; |
| 2365 | } else { |
| 2366 | goto CommandBegin; |
| 2367 | } |
| 2368 | CommandPostWrapCopy: |
| 2369 | { |
| 2370 | int wrap_guard = s->ringbuffer_size - pos; |
| 2371 | while (--i >= 0) { |
| 2372 | s->ringbuffer[pos] = |
| 2373 | s->ringbuffer[(pos - s->distance_code) & s->ringbuffer_mask]; |
| 2374 | ++pos; |
| 2375 | if (BROTLI_PREDICT_FALSE(--wrap_guard == 0)(__builtin_expect(--wrap_guard == 0, 0))) { |
| 2376 | s->state = BROTLI_STATE_COMMAND_POST_WRITE_2; |
| 2377 | goto saveStateAndReturn; |
| 2378 | } |
| 2379 | } |
| 2380 | } |
| 2381 | if (s->meta_block_remaining_len <= 0) { |
| 2382 | /* Next metablock, if any. */ |
| 2383 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2384 | goto saveStateAndReturn; |
| 2385 | } else { |
| 2386 | goto CommandBegin; |
| 2387 | } |
| 2388 | |
| 2389 | NextLiteralBlock: |
| 2390 | BROTLI_SAFE_WITH_STATUS(DecodeLiteralBlockSwitch(s)){ BrotliDecoderErrorCode status; if (safe) { status = SafeDecodeLiteralBlockSwitch (s); } else { status = DecodeLiteralBlockSwitch(s); } if (status != BROTLI_DECODER_SUCCESS) { result = status; goto saveStateAndReturn ; } }; |
| 2391 | goto CommandInner; |
| 2392 | |
| 2393 | saveStateAndReturn: |
| 2394 | s->pos = pos; |
| 2395 | s->loop_counter = i; |
| 2396 | return result; |
| 2397 | } |
| 2398 | |
| 2399 | #undef BROTLI_SAFE |
| 2400 | |
| 2401 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode ProcessCommands( |
| 2402 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2403 | return ProcessCommandsInternal(0, s); |
| 2404 | } |
| 2405 | |
| 2406 | static BROTLI_NOINLINE__attribute__((__noinline__)) BrotliDecoderErrorCode SafeProcessCommands( |
| 2407 | BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2408 | return ProcessCommandsInternal(1, s); |
| 2409 | } |
| 2410 | |
| 2411 | BrotliDecoderResult BrotliDecoderDecompress( |
| 2412 | size_t encoded_size, |
| 2413 | const uint8_t encoded_buffer[BROTLI_ARRAY_PARAM(encoded_size)], |
| 2414 | size_t* decoded_size, |
| 2415 | uint8_t decoded_buffer[BROTLI_ARRAY_PARAM(*decoded_size)]) { |
| 2416 | BrotliDecoderStateBrotliDecoderStateInternal s; |
| 2417 | BrotliDecoderResult result; |
| 2418 | size_t total_out = 0; |
| 2419 | size_t available_in = encoded_size; |
| 2420 | const uint8_t* next_in = encoded_buffer; |
| 2421 | size_t available_out = *decoded_size; |
| 2422 | uint8_t* next_out = decoded_buffer; |
| 2423 | if (!BrotliDecoderStateInit(&s, 0, 0, 0)) { |
| 2424 | return BROTLI_DECODER_RESULT_ERROR; |
| 2425 | } |
| 2426 | result = BrotliDecoderDecompressStream( |
| 2427 | &s, &available_in, &next_in, &available_out, &next_out, &total_out); |
| 2428 | *decoded_size = total_out; |
| 2429 | BrotliDecoderStateCleanup(&s); |
| 2430 | if (result != BROTLI_DECODER_RESULT_SUCCESS) { |
| 2431 | result = BROTLI_DECODER_RESULT_ERROR; |
| 2432 | } |
| 2433 | return result; |
| 2434 | } |
| 2435 | |
| 2436 | /* Invariant: input stream is never overconsumed: |
| 2437 | - invalid input implies that the whole stream is invalid -> any amount of |
| 2438 | input could be read and discarded |
| 2439 | - when result is "needs more input", then at least one more byte is REQUIRED |
| 2440 | to complete decoding; all input data MUST be consumed by decoder, so |
| 2441 | client could swap the input buffer |
| 2442 | - when result is "needs more output" decoder MUST ensure that it doesn't |
| 2443 | hold more than 7 bits in bit reader; this saves client from swapping input |
| 2444 | buffer ahead of time |
| 2445 | - when result is "success" decoder MUST return all unused data back to input |
| 2446 | buffer; this is possible because the invariant is held on enter */ |
| 2447 | BrotliDecoderResult BrotliDecoderDecompressStream( |
| 2448 | BrotliDecoderStateBrotliDecoderStateInternal* s, size_t* available_in, const uint8_t** next_in, |
| 2449 | size_t* available_out, uint8_t** next_out, size_t* total_out) { |
| 2450 | BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS; |
| 2451 | BrotliBitReader* br = &s->br; |
| 2452 | size_t input_size = *available_in; |
| 2453 | #define BROTLI_SAVE_ERROR_CODE(code) \ |
| 2454 | SaveErrorCode(s, (code), input_size - *available_in) |
| 2455 | /* Ensure that |total_out| is set, even if no data will ever be pushed out. */ |
| 2456 | if (total_out) { |
| 2457 | *total_out = s->partial_pos_out; |
| 2458 | } |
| 2459 | /* Do not try to process further in a case of unrecoverable error. */ |
| 2460 | if ((int)s->error_code < 0) { |
| 2461 | return BROTLI_DECODER_RESULT_ERROR; |
| 2462 | } |
| 2463 | if (*available_out && (!next_out || !*next_out)) { |
| 2464 | return BROTLI_SAVE_ERROR_CODE( |
| 2465 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_INVALID_ARGUMENTS)((void)(0), BROTLI_DECODER_ERROR_INVALID_ARGUMENTS)); |
| 2466 | } |
| 2467 | if (!*available_out) next_out = 0; |
| 2468 | if (s->buffer_length == 0) { /* Just connect bit reader to input stream. */ |
| 2469 | BrotliBitReaderSetInput(br, *next_in, *available_in); |
| 2470 | } else { |
| 2471 | /* At least one byte of input is required. More than one byte of input may |
| 2472 | be required to complete the transaction -> reading more data must be |
| 2473 | done in a loop -> do it in a main loop. */ |
| 2474 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2475 | BrotliBitReaderSetInput(br, &s->buffer.u8[0], s->buffer_length); |
| 2476 | } |
| 2477 | /* State machine */ |
| 2478 | for (;;) { |
| 2479 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2480 | /* Error, needs more input/output. */ |
| 2481 | if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { |
| 2482 | if (s->ringbuffer != 0) { /* Pro-actively push output. */ |
| 2483 | BrotliDecoderErrorCode intermediate_result = WriteRingBuffer(s, |
| 2484 | available_out, next_out, total_out, BROTLI_TRUE1); |
| 2485 | /* WriteRingBuffer checks s->meta_block_remaining_len validity. */ |
| 2486 | if ((int)intermediate_result < 0) { |
| 2487 | result = intermediate_result; |
| 2488 | break; |
| 2489 | } |
| 2490 | } |
| 2491 | if (s->buffer_length != 0) { /* Used with internal buffer. */ |
| 2492 | if (br->next_in == br->last_in) { |
| 2493 | /* Successfully finished read transaction. |
| 2494 | Accumulator contains less than 8 bits, because internal buffer |
| 2495 | is expanded byte-by-byte until it is enough to complete read. */ |
| 2496 | s->buffer_length = 0; |
| 2497 | /* Switch to input stream and restart. */ |
| 2498 | result = BROTLI_DECODER_SUCCESS; |
| 2499 | BrotliBitReaderSetInput(br, *next_in, *available_in); |
| 2500 | continue; |
| 2501 | } else if (*available_in != 0) { |
| 2502 | /* Not enough data in buffer, but can take one more byte from |
| 2503 | input stream. */ |
| 2504 | result = BROTLI_DECODER_SUCCESS; |
| 2505 | BROTLI_DCHECK(s->buffer_length < 8); |
| 2506 | s->buffer.u8[s->buffer_length] = **next_in; |
| 2507 | s->buffer_length++; |
| 2508 | BrotliBitReaderSetInput(br, &s->buffer.u8[0], s->buffer_length); |
| 2509 | (*next_in)++; |
| 2510 | (*available_in)--; |
| 2511 | /* Retry with more data in buffer. */ |
| 2512 | continue; |
| 2513 | } |
| 2514 | /* Can't finish reading and no more input. */ |
| 2515 | break; |
| 2516 | } else { /* Input stream doesn't contain enough input. */ |
| 2517 | /* Copy tail to internal buffer and return. */ |
| 2518 | *next_in = br->next_in; |
| 2519 | *available_in = BrotliBitReaderGetAvailIn(br); |
| 2520 | while (*available_in) { |
| 2521 | s->buffer.u8[s->buffer_length] = **next_in; |
| 2522 | s->buffer_length++; |
| 2523 | (*next_in)++; |
| 2524 | (*available_in)--; |
| 2525 | } |
| 2526 | break; |
| 2527 | } |
| 2528 | /* Unreachable. */ |
| 2529 | } |
| 2530 | |
| 2531 | /* Fail or needs more output. */ |
| 2532 | |
| 2533 | if (s->buffer_length != 0) { |
| 2534 | /* Just consumed the buffered input and produced some output. Otherwise |
| 2535 | it would result in "needs more input". Reset internal buffer. */ |
| 2536 | s->buffer_length = 0; |
| 2537 | } else { |
| 2538 | /* Using input stream in last iteration. When decoder switches to input |
| 2539 | stream it has less than 8 bits in accumulator, so it is safe to |
| 2540 | return unused accumulator bits there. */ |
| 2541 | BrotliBitReaderUnload(br); |
| 2542 | *available_in = BrotliBitReaderGetAvailIn(br); |
| 2543 | *next_in = br->next_in; |
| 2544 | } |
| 2545 | break; |
| 2546 | } |
| 2547 | switch (s->state) { |
| 2548 | case BROTLI_STATE_UNINITED: |
| 2549 | /* Prepare to the first read. */ |
| 2550 | if (!BrotliWarmupBitReader(br)) { |
| 2551 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2552 | break; |
| 2553 | } |
| 2554 | /* Decode window size. */ |
| 2555 | result = DecodeWindowBits(s, br); /* Reads 1..8 bits. */ |
| 2556 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2557 | break; |
| 2558 | } |
| 2559 | if (s->large_window) { |
| 2560 | s->state = BROTLI_STATE_LARGE_WINDOW_BITS; |
| 2561 | break; |
| 2562 | } |
| 2563 | s->state = BROTLI_STATE_INITIALIZE; |
| 2564 | break; |
| 2565 | |
| 2566 | case BROTLI_STATE_LARGE_WINDOW_BITS: { |
| 2567 | brotli_reg_tuint64_t bits; |
| 2568 | if (!BrotliSafeReadBits(br, 6, &bits)) { |
| 2569 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2570 | break; |
| 2571 | } |
| 2572 | s->window_bits = bits & 63u; |
| 2573 | if (s->window_bits < BROTLI_LARGE_MIN_WBITS10 || |
| 2574 | s->window_bits > BROTLI_LARGE_MAX_WBITS30) { |
| 2575 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS)((void)(0), BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS); |
| 2576 | break; |
| 2577 | } |
| 2578 | s->state = BROTLI_STATE_INITIALIZE; |
| 2579 | } |
| 2580 | /* Fall through. */ |
| 2581 | |
| 2582 | case BROTLI_STATE_INITIALIZE: |
| 2583 | BROTLI_LOG_UINT(s->window_bits); |
| 2584 | /* Maximum distance, see section 9.1. of the spec. */ |
| 2585 | s->max_backward_distance = (1 << s->window_bits) - BROTLI_WINDOW_GAP16; |
| 2586 | |
| 2587 | /* Allocate memory for both block_type_trees and block_len_trees. */ |
| 2588 | s->block_type_trees = (HuffmanCode*)BROTLI_DECODER_ALLOC(s,s->alloc_func(s->memory_manager_opaque, sizeof(HuffmanCode ) * 3 * (632 + 396)) |
| 2589 | sizeof(HuffmanCode) * 3 *s->alloc_func(s->memory_manager_opaque, sizeof(HuffmanCode ) * 3 * (632 + 396)) |
| 2590 | (BROTLI_HUFFMAN_MAX_SIZE_258 + BROTLI_HUFFMAN_MAX_SIZE_26))s->alloc_func(s->memory_manager_opaque, sizeof(HuffmanCode ) * 3 * (632 + 396)); |
| 2591 | if (s->block_type_trees == 0) { |
| 2592 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_BLOCK_TYPE_TREES)((void)(0), BROTLI_DECODER_ERROR_ALLOC_BLOCK_TYPE_TREES); |
| 2593 | break; |
| 2594 | } |
| 2595 | s->block_len_trees = |
| 2596 | s->block_type_trees + 3 * BROTLI_HUFFMAN_MAX_SIZE_258632; |
| 2597 | |
| 2598 | s->state = BROTLI_STATE_METABLOCK_BEGIN; |
| 2599 | /* Fall through. */ |
| 2600 | |
| 2601 | case BROTLI_STATE_METABLOCK_BEGIN: |
| 2602 | BrotliDecoderStateMetablockBegin(s); |
| 2603 | BROTLI_LOG_UINT(s->pos); |
| 2604 | s->state = BROTLI_STATE_METABLOCK_HEADER; |
| 2605 | /* Fall through. */ |
| 2606 | |
| 2607 | case BROTLI_STATE_METABLOCK_HEADER: |
| 2608 | result = DecodeMetaBlockLength(s, br); /* Reads 2 - 31 bits. */ |
| 2609 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2610 | break; |
| 2611 | } |
| 2612 | BROTLI_DCHECK(s->meta_block_remaining_len <= |
| 2613 | (int)BROTLI_BLOCK_SIZE_CAP); |
| 2614 | BROTLI_LOG_UINT(s->is_last_metablock); |
| 2615 | BROTLI_LOG_UINT(s->meta_block_remaining_len); |
| 2616 | BROTLI_LOG_UINT(s->is_metadata); |
| 2617 | BROTLI_LOG_UINT(s->is_uncompressed); |
| 2618 | if (s->is_metadata || s->is_uncompressed) { |
| 2619 | if (!BrotliJumpToByteBoundary(br)) { |
| 2620 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_PADDING_1)((void)(0), BROTLI_DECODER_ERROR_FORMAT_PADDING_1); |
| 2621 | break; |
| 2622 | } |
| 2623 | } |
| 2624 | if (s->is_metadata) { |
| 2625 | s->state = BROTLI_STATE_METADATA; |
| 2626 | if (s->metadata_start_func) { |
| 2627 | s->metadata_start_func(s->metadata_callback_opaque, |
| 2628 | (size_t)s->meta_block_remaining_len); |
| 2629 | } |
| 2630 | break; |
| 2631 | } |
| 2632 | if (s->meta_block_remaining_len == 0) { |
| 2633 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2634 | break; |
| 2635 | } |
| 2636 | BrotliCalculateRingBufferSize(s); |
| 2637 | if (s->is_uncompressed) { |
| 2638 | s->state = BROTLI_STATE_UNCOMPRESSED; |
| 2639 | break; |
| 2640 | } |
| 2641 | s->state = BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER; |
| 2642 | /* Fall through. */ |
| 2643 | |
| 2644 | case BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER: { |
| 2645 | BrotliMetablockHeaderArena* h = &s->arena.header; |
| 2646 | s->loop_counter = 0; |
| 2647 | /* Initialize compressed metablock header arena. */ |
| 2648 | h->sub_loop_counter = 0; |
| 2649 | /* Make small negative indexes addressable. */ |
| 2650 | h->symbol_lists = |
| 2651 | &h->symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH15 + 1]; |
| 2652 | h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; |
| 2653 | h->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE; |
| 2654 | h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE; |
| 2655 | s->state = BROTLI_STATE_HUFFMAN_CODE_0; |
| 2656 | } |
| 2657 | /* Fall through. */ |
| 2658 | |
| 2659 | case BROTLI_STATE_HUFFMAN_CODE_0: |
| 2660 | if (s->loop_counter >= 3) { |
| 2661 | s->state = BROTLI_STATE_METABLOCK_HEADER_2; |
| 2662 | break; |
| 2663 | } |
| 2664 | /* Reads 1..11 bits. */ |
| 2665 | result = DecodeVarLenUint8(s, br, &s->num_block_types[s->loop_counter]); |
| 2666 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2667 | break; |
| 2668 | } |
| 2669 | s->num_block_types[s->loop_counter]++; |
| 2670 | BROTLI_LOG_UINT(s->num_block_types[s->loop_counter]); |
| 2671 | if (s->num_block_types[s->loop_counter] < 2) { |
| 2672 | s->loop_counter++; |
| 2673 | break; |
| 2674 | } |
| 2675 | s->state = BROTLI_STATE_HUFFMAN_CODE_1; |
| 2676 | /* Fall through. */ |
| 2677 | |
| 2678 | case BROTLI_STATE_HUFFMAN_CODE_1: { |
| 2679 | brotli_reg_tuint64_t alphabet_size = s->num_block_types[s->loop_counter] + 2; |
| 2680 | int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_258632; |
| 2681 | result = ReadHuffmanCode(alphabet_size, alphabet_size, |
| 2682 | &s->block_type_trees[tree_offset], NULL((void*)0), s); |
| 2683 | if (result != BROTLI_DECODER_SUCCESS) break; |
| 2684 | s->state = BROTLI_STATE_HUFFMAN_CODE_2; |
| 2685 | } |
| 2686 | /* Fall through. */ |
| 2687 | |
| 2688 | case BROTLI_STATE_HUFFMAN_CODE_2: { |
| 2689 | brotli_reg_tuint64_t alphabet_size = BROTLI_NUM_BLOCK_LEN_SYMBOLS26; |
| 2690 | int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_26396; |
| 2691 | result = ReadHuffmanCode(alphabet_size, alphabet_size, |
| 2692 | &s->block_len_trees[tree_offset], NULL((void*)0), s); |
| 2693 | if (result != BROTLI_DECODER_SUCCESS) break; |
| 2694 | s->state = BROTLI_STATE_HUFFMAN_CODE_3; |
| 2695 | } |
| 2696 | /* Fall through. */ |
| 2697 | |
| 2698 | case BROTLI_STATE_HUFFMAN_CODE_3: { |
| 2699 | int tree_offset = s->loop_counter * BROTLI_HUFFMAN_MAX_SIZE_26396; |
| 2700 | if (!SafeReadBlockLength(s, &s->block_length[s->loop_counter], |
| 2701 | &s->block_len_trees[tree_offset], br)) { |
| 2702 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2703 | break; |
| 2704 | } |
| 2705 | BROTLI_LOG_UINT(s->block_length[s->loop_counter]); |
| 2706 | s->loop_counter++; |
| 2707 | s->state = BROTLI_STATE_HUFFMAN_CODE_0; |
| 2708 | break; |
| 2709 | } |
| 2710 | |
| 2711 | case BROTLI_STATE_UNCOMPRESSED: { |
| 2712 | result = CopyUncompressedBlockToOutput( |
| 2713 | available_out, next_out, total_out, s); |
| 2714 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2715 | break; |
| 2716 | } |
| 2717 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2718 | break; |
| 2719 | } |
| 2720 | |
| 2721 | case BROTLI_STATE_METADATA: |
| 2722 | result = SkipMetadataBlock(s); |
| 2723 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2724 | break; |
| 2725 | } |
| 2726 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2727 | break; |
| 2728 | |
| 2729 | case BROTLI_STATE_METABLOCK_HEADER_2: { |
| 2730 | brotli_reg_tuint64_t bits; |
| 2731 | if (!BrotliSafeReadBits(br, 6, &bits)) { |
| 2732 | result = BROTLI_DECODER_NEEDS_MORE_INPUT; |
| 2733 | break; |
| 2734 | } |
| 2735 | s->distance_postfix_bits = bits & BitMask(2); |
| 2736 | bits >>= 2; |
| 2737 | s->num_direct_distance_codes = bits << s->distance_postfix_bits; |
| 2738 | BROTLI_LOG_UINT(s->num_direct_distance_codes); |
| 2739 | BROTLI_LOG_UINT(s->distance_postfix_bits); |
| 2740 | s->context_modes = |
| 2741 | (uint8_t*)BROTLI_DECODER_ALLOC(s, (size_t)s->num_block_types[0])s->alloc_func(s->memory_manager_opaque, (size_t)s->num_block_types [0]); |
| 2742 | if (s->context_modes == 0) { |
| 2743 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MODES)((void)(0), BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MODES); |
| 2744 | break; |
| 2745 | } |
| 2746 | s->loop_counter = 0; |
| 2747 | s->state = BROTLI_STATE_CONTEXT_MODES; |
| 2748 | } |
| 2749 | /* Fall through. */ |
| 2750 | |
| 2751 | case BROTLI_STATE_CONTEXT_MODES: |
| 2752 | result = ReadContextModes(s); |
| 2753 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2754 | break; |
| 2755 | } |
| 2756 | s->state = BROTLI_STATE_CONTEXT_MAP_1; |
| 2757 | /* Fall through. */ |
| 2758 | |
| 2759 | case BROTLI_STATE_CONTEXT_MAP_1: |
| 2760 | result = DecodeContextMap( |
| 2761 | s->num_block_types[0] << BROTLI_LITERAL_CONTEXT_BITS6, |
| 2762 | &s->num_literal_htrees, &s->context_map, s); |
| 2763 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2764 | break; |
| 2765 | } |
| 2766 | DetectTrivialLiteralBlockTypes(s); |
| 2767 | s->state = BROTLI_STATE_CONTEXT_MAP_2; |
| 2768 | /* Fall through. */ |
| 2769 | |
| 2770 | case BROTLI_STATE_CONTEXT_MAP_2: { |
| 2771 | brotli_reg_tuint64_t npostfix = s->distance_postfix_bits; |
| 2772 | brotli_reg_tuint64_t ndirect = s->num_direct_distance_codes; |
| 2773 | brotli_reg_tuint64_t distance_alphabet_size_max = BROTLI_DISTANCE_ALPHABET_SIZE(( 16 + (ndirect) + ((24U) << ((npostfix) + 1))) |
| 2774 | npostfix, ndirect, BROTLI_MAX_DISTANCE_BITS)( 16 + (ndirect) + ((24U) << ((npostfix) + 1))); |
| 2775 | brotli_reg_tuint64_t distance_alphabet_size_limit = distance_alphabet_size_max; |
| 2776 | BROTLI_BOOLint allocation_success = BROTLI_TRUE1; |
| 2777 | if (s->large_window) { |
| 2778 | BrotliDistanceCodeLimit limit = BrotliCalculateDistanceCodeLimit( |
| 2779 | BROTLI_MAX_ALLOWED_DISTANCE0x7FFFFFFC, (uint32_t)npostfix, |
| 2780 | (uint32_t)ndirect); |
| 2781 | distance_alphabet_size_max = BROTLI_DISTANCE_ALPHABET_SIZE(( 16 + (ndirect) + ((62U) << ((npostfix) + 1))) |
| 2782 | npostfix, ndirect, BROTLI_LARGE_MAX_DISTANCE_BITS)( 16 + (ndirect) + ((62U) << ((npostfix) + 1))); |
| 2783 | distance_alphabet_size_limit = limit.max_alphabet_size; |
| 2784 | } |
| 2785 | result = DecodeContextMap( |
| 2786 | s->num_block_types[2] << BROTLI_DISTANCE_CONTEXT_BITS2, |
| 2787 | &s->num_dist_htrees, &s->dist_context_map, s); |
| 2788 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2789 | break; |
| 2790 | } |
| 2791 | allocation_success &= BrotliDecoderHuffmanTreeGroupInit( |
| 2792 | s, &s->literal_hgroup, BROTLI_NUM_LITERAL_SYMBOLS256, |
| 2793 | BROTLI_NUM_LITERAL_SYMBOLS256, s->num_literal_htrees); |
| 2794 | allocation_success &= BrotliDecoderHuffmanTreeGroupInit( |
| 2795 | s, &s->insert_copy_hgroup, BROTLI_NUM_COMMAND_SYMBOLS704, |
| 2796 | BROTLI_NUM_COMMAND_SYMBOLS704, s->num_block_types[1]); |
| 2797 | allocation_success &= BrotliDecoderHuffmanTreeGroupInit( |
| 2798 | s, &s->distance_hgroup, distance_alphabet_size_max, |
| 2799 | distance_alphabet_size_limit, s->num_dist_htrees); |
| 2800 | if (!allocation_success) { |
| 2801 | return BROTLI_SAVE_ERROR_CODE( |
| 2802 | BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_TREE_GROUPS)((void)(0), BROTLI_DECODER_ERROR_ALLOC_TREE_GROUPS)); |
| 2803 | } |
| 2804 | s->loop_counter = 0; |
| 2805 | s->state = BROTLI_STATE_TREE_GROUP; |
| 2806 | } |
| 2807 | /* Fall through. */ |
| 2808 | |
| 2809 | case BROTLI_STATE_TREE_GROUP: { |
| 2810 | HuffmanTreeGroup* hgroup = NULL((void*)0); |
| 2811 | switch (s->loop_counter) { |
| 2812 | case 0: hgroup = &s->literal_hgroup; break; |
| 2813 | case 1: hgroup = &s->insert_copy_hgroup; break; |
| 2814 | case 2: hgroup = &s->distance_hgroup; break; |
| 2815 | default: return BROTLI_SAVE_ERROR_CODE(BROTLI_FAILURE(((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE) |
| 2816 | BROTLI_DECODER_ERROR_UNREACHABLE)((void)(0), BROTLI_DECODER_ERROR_UNREACHABLE)); /* COV_NF_LINE */ |
| 2817 | } |
| 2818 | result = HuffmanTreeGroupDecode(hgroup, s); |
| 2819 | if (result != BROTLI_DECODER_SUCCESS) break; |
| 2820 | s->loop_counter++; |
| 2821 | if (s->loop_counter < 3) { |
| 2822 | break; |
| 2823 | } |
| 2824 | s->state = BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY; |
| 2825 | } |
| 2826 | /* Fall through. */ |
| 2827 | |
| 2828 | case BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY: |
| 2829 | PrepareLiteralDecoding(s); |
| 2830 | s->dist_context_map_slice = s->dist_context_map; |
| 2831 | s->htree_command = s->insert_copy_hgroup.htrees[0]; |
| 2832 | if (!BrotliEnsureRingBuffer(s)) { |
| 2833 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2)((void)(0), BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2); |
| 2834 | break; |
| 2835 | } |
| 2836 | CalculateDistanceLut(s); |
| 2837 | s->state = BROTLI_STATE_COMMAND_BEGIN; |
| 2838 | /* Fall through. */ |
| 2839 | |
| 2840 | case BROTLI_STATE_COMMAND_BEGIN: |
| 2841 | /* Fall through. */ |
| 2842 | case BROTLI_STATE_COMMAND_INNER: |
| 2843 | /* Fall through. */ |
| 2844 | case BROTLI_STATE_COMMAND_POST_DECODE_LITERALS: |
| 2845 | /* Fall through. */ |
| 2846 | case BROTLI_STATE_COMMAND_POST_WRAP_COPY: |
| 2847 | result = ProcessCommands(s); |
| 2848 | if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) { |
| 2849 | result = SafeProcessCommands(s); |
| 2850 | } |
| 2851 | break; |
| 2852 | |
| 2853 | case BROTLI_STATE_COMMAND_INNER_WRITE: |
| 2854 | /* Fall through. */ |
| 2855 | case BROTLI_STATE_COMMAND_POST_WRITE_1: |
| 2856 | /* Fall through. */ |
| 2857 | case BROTLI_STATE_COMMAND_POST_WRITE_2: |
| 2858 | result = WriteRingBuffer( |
| 2859 | s, available_out, next_out, total_out, BROTLI_FALSE0); |
| 2860 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2861 | break; |
| 2862 | } |
| 2863 | WrapRingBuffer(s); |
| 2864 | if (s->ringbuffer_size == 1 << s->window_bits) { |
| 2865 | s->max_distance = s->max_backward_distance; |
| 2866 | } |
| 2867 | if (s->state == BROTLI_STATE_COMMAND_POST_WRITE_1) { |
| 2868 | BrotliDecoderCompoundDictionary* addon = s->compound_dictionary; |
| 2869 | if (addon && (addon->br_length != addon->br_copied)) { |
| 2870 | s->pos += CopyFromCompoundDictionary(s, s->pos); |
| 2871 | if (s->pos >= s->ringbuffer_size) continue; |
| 2872 | } |
| 2873 | if (s->meta_block_remaining_len == 0) { |
| 2874 | /* Next metablock, if any. */ |
| 2875 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2876 | } else { |
| 2877 | s->state = BROTLI_STATE_COMMAND_BEGIN; |
| 2878 | } |
| 2879 | break; |
| 2880 | } else if (s->state == BROTLI_STATE_COMMAND_POST_WRITE_2) { |
| 2881 | s->state = BROTLI_STATE_COMMAND_POST_WRAP_COPY; |
| 2882 | } else { /* BROTLI_STATE_COMMAND_INNER_WRITE */ |
| 2883 | if (s->loop_counter == 0) { |
| 2884 | if (s->meta_block_remaining_len == 0) { |
| 2885 | s->state = BROTLI_STATE_METABLOCK_DONE; |
| 2886 | } else { |
| 2887 | s->state = BROTLI_STATE_COMMAND_POST_DECODE_LITERALS; |
| 2888 | } |
| 2889 | break; |
| 2890 | } |
| 2891 | s->state = BROTLI_STATE_COMMAND_INNER; |
| 2892 | } |
| 2893 | break; |
| 2894 | |
| 2895 | case BROTLI_STATE_METABLOCK_DONE: |
| 2896 | if (s->meta_block_remaining_len < 0) { |
| 2897 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_2)((void)(0), BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_2); |
| 2898 | break; |
| 2899 | } |
| 2900 | BrotliDecoderStateCleanupAfterMetablock(s); |
| 2901 | if (!s->is_last_metablock) { |
| 2902 | s->state = BROTLI_STATE_METABLOCK_BEGIN; |
| 2903 | break; |
| 2904 | } |
| 2905 | if (!BrotliJumpToByteBoundary(br)) { |
| 2906 | result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_PADDING_2)((void)(0), BROTLI_DECODER_ERROR_FORMAT_PADDING_2); |
| 2907 | break; |
| 2908 | } |
| 2909 | if (s->buffer_length == 0) { |
| 2910 | BrotliBitReaderUnload(br); |
| 2911 | *available_in = BrotliBitReaderGetAvailIn(br); |
| 2912 | *next_in = br->next_in; |
| 2913 | } |
| 2914 | s->state = BROTLI_STATE_DONE; |
| 2915 | /* Fall through. */ |
| 2916 | |
| 2917 | case BROTLI_STATE_DONE: |
| 2918 | if (s->ringbuffer != 0) { |
| 2919 | result = WriteRingBuffer( |
| 2920 | s, available_out, next_out, total_out, BROTLI_TRUE1); |
| 2921 | if (result != BROTLI_DECODER_SUCCESS) { |
| 2922 | break; |
| 2923 | } |
| 2924 | } |
| 2925 | return BROTLI_SAVE_ERROR_CODE(result); |
| 2926 | } |
| 2927 | } |
| 2928 | return BROTLI_SAVE_ERROR_CODE(result); |
| 2929 | #undef BROTLI_SAVE_ERROR_CODE |
| 2930 | } |
| 2931 | |
| 2932 | BROTLI_BOOLint BrotliDecoderHasMoreOutput(const BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2933 | /* After unrecoverable error remaining output is considered nonsensical. */ |
| 2934 | if ((int)s->error_code < 0) { |
| 2935 | return BROTLI_FALSE0; |
| 2936 | } |
| 2937 | return TO_BROTLI_BOOL((!!(s->ringbuffer != 0 && UnwrittenBytes(s, 0) != 0 ) ? 1 : 0) |
| 2938 | s->ringbuffer != 0 && UnwrittenBytes(s, BROTLI_FALSE) != 0)(!!(s->ringbuffer != 0 && UnwrittenBytes(s, 0) != 0 ) ? 1 : 0); |
| 2939 | } |
| 2940 | |
| 2941 | const uint8_t* BrotliDecoderTakeOutput(BrotliDecoderStateBrotliDecoderStateInternal* s, size_t* size) { |
| 2942 | uint8_t* result = 0; |
| 2943 | size_t available_out = *size ? *size : 1u << 24; |
| 2944 | size_t requested_out = available_out; |
| 2945 | BrotliDecoderErrorCode status; |
| 2946 | if ((s->ringbuffer == 0) || ((int)s->error_code < 0)) { |
| 2947 | *size = 0; |
| 2948 | return 0; |
| 2949 | } |
| 2950 | WrapRingBuffer(s); |
| 2951 | status = WriteRingBuffer(s, &available_out, &result, 0, BROTLI_TRUE1); |
| 2952 | /* Either WriteRingBuffer returns those "success" codes... */ |
| 2953 | if (status == BROTLI_DECODER_SUCCESS || |
| 2954 | status == BROTLI_DECODER_NEEDS_MORE_OUTPUT) { |
| 2955 | *size = requested_out - available_out; |
| 2956 | } else { |
| 2957 | /* ... or stream is broken. Normally this should be caught by |
| 2958 | BrotliDecoderDecompressStream, this is just a safeguard. */ |
| 2959 | if ((int)status < 0) SaveErrorCode(s, status, 0); |
| 2960 | *size = 0; |
| 2961 | result = 0; |
| 2962 | } |
| 2963 | return result; |
| 2964 | } |
| 2965 | |
| 2966 | BROTLI_BOOLint BrotliDecoderIsUsed(const BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2967 | return TO_BROTLI_BOOL(s->state != BROTLI_STATE_UNINITED ||(!!(s->state != BROTLI_STATE_UNINITED || BrotliGetAvailableBits (&s->br) != 0) ? 1 : 0) |
| 2968 | BrotliGetAvailableBits(&s->br) != 0)(!!(s->state != BROTLI_STATE_UNINITED || BrotliGetAvailableBits (&s->br) != 0) ? 1 : 0); |
| 2969 | } |
| 2970 | |
| 2971 | BROTLI_BOOLint BrotliDecoderIsFinished(const BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2972 | return TO_BROTLI_BOOL(s->state == BROTLI_STATE_DONE)(!!(s->state == BROTLI_STATE_DONE) ? 1 : 0) && |
| 2973 | !BrotliDecoderHasMoreOutput(s); |
| 2974 | } |
| 2975 | |
| 2976 | BrotliDecoderErrorCode BrotliDecoderGetErrorCode(const BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 2977 | return (BrotliDecoderErrorCode)s->error_code; |
| 2978 | } |
| 2979 | |
| 2980 | const char* BrotliDecoderErrorString(BrotliDecoderErrorCode c) { |
| 2981 | switch (c) { |
| 2982 | #define BROTLI_ERROR_CODE_CASE_(PREFIX, NAME, CODE) \ |
| 2983 | case BROTLI_DECODER ## PREFIX ## NAME: return #PREFIX #NAME; |
| 2984 | #define BROTLI_NOTHING_ |
| 2985 | BROTLI_DECODER_ERROR_CODES_LIST(BROTLI_ERROR_CODE_CASE_, BROTLI_NOTHING_)BROTLI_ERROR_CODE_CASE_(_, NO_ERROR, 0) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_, SUCCESS, 1) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_, NEEDS_MORE_INPUT , 2) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_, NEEDS_MORE_OUTPUT , 3) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_, EXUBERANT_NIBBLE , -1) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_, RESERVED, -2) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_ , EXUBERANT_META_NIBBLE, -3) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, SIMPLE_HUFFMAN_ALPHABET, -4) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_, SIMPLE_HUFFMAN_SAME, -5) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_, CL_SPACE , -6) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_, HUFFMAN_SPACE, -7) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_(_ERROR_FORMAT_ , CONTEXT_MAP_REPEAT, -8) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, BLOCK_LENGTH_1, -9) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, BLOCK_LENGTH_2, -10) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, TRANSFORM, -11) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, DICTIONARY, -12) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, WINDOW_BITS, -13) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, PADDING_1, -14) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, PADDING_2, -15) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, DISTANCE, -16) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_FORMAT_, BLOCK_SWITCH, -17) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_, COMPOUND_DICTIONARY, -18) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_, DICTIONARY_NOT_SET, -19) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_, INVALID_ARGUMENTS, -20) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, CONTEXT_MODES, -21) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, TREE_GROUPS, -22) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, CONTEXT_MAP, -25) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, RING_BUFFER_1, -26) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, RING_BUFFER_2, -27) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_ALLOC_, BLOCK_TYPE_TREES, -30) BROTLI_NOTHING_ BROTLI_ERROR_CODE_CASE_ (_ERROR_, UNREACHABLE, -31) |
| 2986 | #undef BROTLI_ERROR_CODE_CASE_ |
| 2987 | #undef BROTLI_NOTHING_ |
| 2988 | default: return "INVALID"; |
| 2989 | } |
| 2990 | } |
| 2991 | |
| 2992 | uint32_t BrotliDecoderVersion(void) { |
| 2993 | return BROTLI_VERSION((1 << 24) | (2 << 12) | 0); |
| 2994 | } |
| 2995 | |
| 2996 | void BrotliDecoderSetMetadataCallbacks( |
| 2997 | BrotliDecoderStateBrotliDecoderStateInternal* state, |
| 2998 | brotli_decoder_metadata_start_func start_func, |
| 2999 | brotli_decoder_metadata_chunk_func chunk_func, void* opaque) { |
| 3000 | state->metadata_start_func = start_func; |
| 3001 | state->metadata_chunk_func = chunk_func; |
| 3002 | state->metadata_callback_opaque = opaque; |
| 3003 | } |
| 3004 | |
| 3005 | /* Escalate internal functions visibility; for testing purposes only. */ |
| 3006 | #if defined(BROTLI_TEST) |
| 3007 | BROTLI_BOOLint BrotliSafeReadSymbolForTest( |
| 3008 | const HuffmanCode*, BrotliBitReader*, brotli_reg_tuint64_t*); |
| 3009 | BROTLI_BOOLint BrotliSafeReadSymbolForTest( |
| 3010 | const HuffmanCode* table, BrotliBitReader* br, brotli_reg_tuint64_t* result) { |
| 3011 | return SafeReadSymbol(table, br, result); |
| 3012 | } |
| 3013 | void BrotliInverseMoveToFrontTransformForTest( |
| 3014 | uint8_t*, brotli_reg_tuint64_t, BrotliDecoderStateBrotliDecoderStateInternal*); |
| 3015 | void BrotliInverseMoveToFrontTransformForTest( |
| 3016 | uint8_t* v, brotli_reg_tuint64_t l, BrotliDecoderStateBrotliDecoderStateInternal* s) { |
| 3017 | InverseMoveToFrontTransform(v, l, s); |
| 3018 | } |
| 3019 | #endif |
| 3020 | |
| 3021 | #if defined(__cplusplus) || defined(c_plusplus) |
| 3022 | } /* extern "C" */ |
| 3023 | #endif |