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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 two-pass processing: in the first pass we save
the found backward matches and literal bytes into a buffer, and in the
second pass we emit them into the bit stream using prefix codes built based
on the actual command and literal byte histograms. */
#include "../common/constants.h"
#include "../common/platform.h"
#include <brotli/types.h>
#include "entropy_encode.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
/* TODO: turn to macro. */
static const size_t kCompressFragmentTwoPassBlockSize = 1 << 17;
typedef struct BrotliTwoPassArena {
uint32_t lit_histo[256];
uint8_t lit_depth[256];
uint16_t lit_bits[256];
uint32_t cmd_histo[128];
uint8_t cmd_depth[128];
uint16_t cmd_bits[128];
/* BuildAndStoreCommandPrefixCode */
HuffmanTree tmp_tree[2 * BROTLI_NUM_LITERAL_SYMBOLS + 1];
uint8_t tmp_depth[BROTLI_NUM_COMMAND_SYMBOLS];
uint16_t tmp_bits[64];
} BrotliTwoPassArena;
/* 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.
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: "command_buf" and "literal_buf" point to at least
kCompressFragmentTwoPassBlockSize long arrays.
REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
REQUIRES: "table_size" is a power of two
OUTPUT: maximal copy distance <= |input_size|
OUTPUT: maximal copy distance <= BROTLI_MAX_BACKWARD_LIMIT(18) */
BROTLI_INTERNAL void BrotliCompressFragmentTwoPass(BrotliTwoPassArena* s,
const uint8_t* input,
size_t input_size,
BROTLI_BOOL is_last,
uint32_t* command_buf,
uint8_t* literal_buf,
int* table,
size_t table_size,
size_t* storage_ix,
uint8_t* storage);
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */