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/* Copyright 2015 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at
/* Function for fast encoding of an input fragment, independently from the input
history. This function uses one-pass processing: when we find a backward
match, we immediately emit the corresponding command and literal codes to
the bit stream. */
#include "../common/constants.h"
#include "../common/platform.h"
#include <brotli/types.h>
#include "entropy_encode.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
typedef struct BrotliOnePassArena {
uint8_t lit_depth[256];
uint16_t lit_bits[256];
/* Command and distance prefix codes (each 64 symbols, stored back-to-back)
used for the next block. The command prefix code is over a smaller alphabet
with the following 64 symbols:
0 - 15: insert length code 0, copy length code 0 - 15, same distance
16 - 39: insert length code 0, copy length code 0 - 23
40 - 63: insert length code 0 - 23, copy length code 0
Note that symbols 16 and 40 represent the same code in the full alphabet,
but we do not use either of them. */
uint8_t cmd_depth[128];
uint16_t cmd_bits[128];
uint32_t cmd_histo[128];
/* The compressed form of the command and distance prefix codes for the next
block. */
uint8_t cmd_code[512];
size_t cmd_code_numbits;
HuffmanTree tree[2 * BROTLI_NUM_LITERAL_SYMBOLS + 1];
uint32_t histogram[256];
uint8_t tmp_depth[BROTLI_NUM_COMMAND_SYMBOLS];
uint16_t tmp_bits[64];
} BrotliOnePassArena;
/* Compresses "input" string to the "*storage" buffer as one or more complete
meta-blocks, and updates the "*storage_ix" bit position.
If "is_last" is 1, emits an additional empty last meta-block.
"cmd_depth" and "cmd_bits" contain the command and distance prefix codes
(see comment in encode.h) used for the encoding of this input fragment.
If "is_last" is 0, they are updated to reflect the statistics
of this input fragment, to be used for the encoding of the next fragment.
"*cmd_code_numbits" is the number of bits of the compressed representation
of the command and distance prefix codes, and "cmd_code" is an array of
at least "(*cmd_code_numbits + 7) >> 3" size that contains the compressed
command and distance prefix codes. If "is_last" is 0, these are also
updated to represent the updated "cmd_depth" and "cmd_bits".
REQUIRES: "input_size" is greater than zero, or "is_last" is 1.
REQUIRES: "input_size" is less or equal to maximal metablock size (1 << 24).
REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
REQUIRES: "table_size" is an odd (9, 11, 13, 15) power of two
OUTPUT: maximal copy distance <= |input_size|
OUTPUT: maximal copy distance <= BROTLI_MAX_BACKWARD_LIMIT(18) */
BROTLI_INTERNAL void BrotliCompressFragmentFast(BrotliOnePassArena* s,
const uint8_t* input,
size_t input_size,
BROTLI_BOOL is_last,
int* table, size_t table_size,
size_t* storage_ix,
uint8_t* storage);
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */