1 /* Copyright 2014 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 /* Functions to convert brotli-related data structures into the
8    brotli bit stream. The functions here operate under
9    assumption that there is enough space in the storage, i.e., there are
10    no out-of-range checks anywhere.
11 
12    These functions do bit addressing into a byte array. The byte array
13    is called "storage" and the index to the bit is called storage_ix
14    in function arguments. */
15 
16 #ifndef BROTLI_ENC_BROTLI_BIT_STREAM_H_
17 #define BROTLI_ENC_BROTLI_BIT_STREAM_H_
18 
19 #include "../common/context.h"
20 #include "../common/platform.h"
21 #include <brotli/types.h>
22 #include "./command.h"
23 #include "./entropy_encode.h"
24 #include "./memory.h"
25 #include "./metablock.h"
26 
27 #if defined(__cplusplus) || defined(c_plusplus)
28 extern "C" {
29 #endif
30 
31 /* All Store functions here will use a storage_ix, which is always the bit
32    position for the current storage. */
33 
34 BROTLI_INTERNAL void BrotliStoreHuffmanTree(const uint8_t* depths, size_t num,
35     HuffmanTree* tree, size_t* storage_ix, uint8_t* storage);
36 
37 BROTLI_INTERNAL void BrotliBuildAndStoreHuffmanTreeFast(
38     MemoryManager* m, const uint32_t* histogram, const size_t histogram_total,
39     const size_t max_bits, uint8_t* depth, uint16_t* bits, size_t* storage_ix,
40     uint8_t* storage);
41 
42 /* REQUIRES: length > 0 */
43 /* REQUIRES: length <= (1 << 24) */
44 BROTLI_INTERNAL void BrotliStoreMetaBlock(MemoryManager* m,
45     const uint8_t* input, size_t start_pos, size_t length, size_t mask,
46     uint8_t prev_byte, uint8_t prev_byte2, BROTLI_BOOL is_last,
47     const BrotliEncoderParams* params, ContextType literal_context_mode,
48     const Command* commands, size_t n_commands, const MetaBlockSplit* mb,
49     size_t* storage_ix, uint8_t* storage);
50 
51 /* Stores the meta-block without doing any block splitting, just collects
52    one histogram per block category and uses that for entropy coding.
53    REQUIRES: length > 0
54    REQUIRES: length <= (1 << 24) */
55 BROTLI_INTERNAL void BrotliStoreMetaBlockTrivial(MemoryManager* m,
56     const uint8_t* input, size_t start_pos, size_t length, size_t mask,
57     BROTLI_BOOL is_last, const BrotliEncoderParams* params,
58     const Command* commands, size_t n_commands,
59     size_t* storage_ix, uint8_t* storage);
60 
61 /* Same as above, but uses static prefix codes for histograms with a only a few
62    symbols, and uses static code length prefix codes for all other histograms.
63    REQUIRES: length > 0
64    REQUIRES: length <= (1 << 24) */
65 BROTLI_INTERNAL void BrotliStoreMetaBlockFast(MemoryManager* m,
66     const uint8_t* input, size_t start_pos, size_t length, size_t mask,
67     BROTLI_BOOL is_last, const BrotliEncoderParams* params,
68     const Command* commands, size_t n_commands,
69     size_t* storage_ix, uint8_t* storage);
70 
71 /* This is for storing uncompressed blocks (simple raw storage of
72    bytes-as-bytes).
73    REQUIRES: length > 0
74    REQUIRES: length <= (1 << 24) */
75 BROTLI_INTERNAL void BrotliStoreUncompressedMetaBlock(
76     BROTLI_BOOL is_final_block, const uint8_t* BROTLI_RESTRICT input,
77     size_t position, size_t mask, size_t len,
78     size_t* BROTLI_RESTRICT storage_ix, uint8_t* BROTLI_RESTRICT storage);
79 
80 #if defined(__cplusplus) || defined(c_plusplus)
81 }  /* extern "C" */
82 #endif
83 
84 #endif  /* BROTLI_ENC_BROTLI_BIT_STREAM_H_ */
85