S_New4/include/brotli/decode.h
2023-09-23 03:30:29 +02:00

410 lines
16 KiB
C

/* Copyright 2013 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/
/**
* @file
* API for Brotli decompression.
*/
#ifndef BROTLI_DEC_DECODE_H_
#define BROTLI_DEC_DECODE_H_
#include <brotli/port.h>
#include <brotli/shared_dictionary.h>
#include <brotli/types.h>
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
/**
* Opaque structure that holds decoder state.
*
* Allocated and initialized with ::BrotliDecoderCreateInstance.
* Cleaned up and deallocated with ::BrotliDecoderDestroyInstance.
*/
typedef struct BrotliDecoderStateStruct BrotliDecoderState;
/**
* Result type for ::BrotliDecoderDecompress and
* ::BrotliDecoderDecompressStream functions.
*/
typedef enum {
/** Decoding error, e.g. corrupted input or memory allocation problem. */
BROTLI_DECODER_RESULT_ERROR = 0,
/** Decoding successfully completed. */
BROTLI_DECODER_RESULT_SUCCESS = 1,
/** Partially done; should be called again with more input. */
BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT = 2,
/** Partially done; should be called again with more output. */
BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT = 3
} BrotliDecoderResult;
/**
* Template that evaluates items of ::BrotliDecoderErrorCode.
*
* Example: @code {.cpp}
* // Log Brotli error code.
* switch (brotliDecoderErrorCode) {
* #define CASE_(PREFIX, NAME, CODE) \
* case BROTLI_DECODER ## PREFIX ## NAME: \
* LOG(INFO) << "error code:" << #NAME; \
* break;
* #define NEWLINE_
* BROTLI_DECODER_ERROR_CODES_LIST(CASE_, NEWLINE_)
* #undef CASE_
* #undef NEWLINE_
* default: LOG(FATAL) << "unknown brotli error code";
* }
* @endcode
*/
#define BROTLI_DECODER_ERROR_CODES_LIST(BROTLI_ERROR_CODE, SEPARATOR) \
BROTLI_ERROR_CODE(_, NO_ERROR, 0) SEPARATOR \
/* Same as BrotliDecoderResult values */ \
BROTLI_ERROR_CODE(_, SUCCESS, 1) SEPARATOR \
BROTLI_ERROR_CODE(_, NEEDS_MORE_INPUT, 2) SEPARATOR \
BROTLI_ERROR_CODE(_, NEEDS_MORE_OUTPUT, 3) SEPARATOR \
\
/* Errors caused by invalid input */ \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, EXUBERANT_NIBBLE, -1) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, RESERVED, -2) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, EXUBERANT_META_NIBBLE, -3) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, SIMPLE_HUFFMAN_ALPHABET, -4) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, SIMPLE_HUFFMAN_SAME, -5) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, CL_SPACE, -6) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, HUFFMAN_SPACE, -7) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, CONTEXT_MAP_REPEAT, -8) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, BLOCK_LENGTH_1, -9) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, BLOCK_LENGTH_2, -10) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, TRANSFORM, -11) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, DICTIONARY, -12) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, WINDOW_BITS, -13) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, PADDING_1, -14) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, PADDING_2, -15) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_FORMAT_, DISTANCE, -16) SEPARATOR \
\
/* -17 code is reserved */ \
\
BROTLI_ERROR_CODE(_ERROR_, COMPOUND_DICTIONARY, -18) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_, DICTIONARY_NOT_SET, -19) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_, INVALID_ARGUMENTS, -20) SEPARATOR \
\
/* Memory allocation problems */ \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, CONTEXT_MODES, -21) SEPARATOR \
/* Literal, insert and distance trees together */ \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, TREE_GROUPS, -22) SEPARATOR \
/* -23..-24 codes are reserved for distinct tree groups */ \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, CONTEXT_MAP, -25) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, RING_BUFFER_1, -26) SEPARATOR \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, RING_BUFFER_2, -27) SEPARATOR \
/* -28..-29 codes are reserved for dynamic ring-buffer allocation */ \
BROTLI_ERROR_CODE(_ERROR_ALLOC_, BLOCK_TYPE_TREES, -30) SEPARATOR \
\
/* "Impossible" states */ \
BROTLI_ERROR_CODE(_ERROR_, UNREACHABLE, -31)
/**
* Error code for detailed logging / production debugging.
*
* See ::BrotliDecoderGetErrorCode and ::BROTLI_LAST_ERROR_CODE.
*/
typedef enum {
#define BROTLI_COMMA_ ,
#define BROTLI_ERROR_CODE_ENUM_ITEM_(PREFIX, NAME, CODE) \
BROTLI_DECODER ## PREFIX ## NAME = CODE
BROTLI_DECODER_ERROR_CODES_LIST(BROTLI_ERROR_CODE_ENUM_ITEM_, BROTLI_COMMA_)
} BrotliDecoderErrorCode;
#undef BROTLI_ERROR_CODE_ENUM_ITEM_
#undef BROTLI_COMMA_
/**
* The value of the last error code, negative integer.
*
* All other error code values are in the range from ::BROTLI_LAST_ERROR_CODE
* to @c -1. There are also 4 other possible non-error codes @c 0 .. @c 3 in
* ::BrotliDecoderErrorCode enumeration.
*/
#define BROTLI_LAST_ERROR_CODE BROTLI_DECODER_ERROR_UNREACHABLE
/** Options to be used with ::BrotliDecoderSetParameter. */
typedef enum BrotliDecoderParameter {
/**
* Disable "canny" ring buffer allocation strategy.
*
* Ring buffer is allocated according to window size, despite the real size of
* the content.
*/
BROTLI_DECODER_PARAM_DISABLE_RING_BUFFER_REALLOCATION = 0,
/**
* Flag that determines if "Large Window Brotli" is used.
*/
BROTLI_DECODER_PARAM_LARGE_WINDOW = 1
} BrotliDecoderParameter;
/**
* Sets the specified parameter to the given decoder instance.
*
* @param state decoder instance
* @param param parameter to set
* @param value new parameter value
* @returns ::BROTLI_FALSE if parameter is unrecognized, or value is invalid
* @returns ::BROTLI_TRUE if value is accepted
*/
BROTLI_DEC_API BROTLI_BOOL BrotliDecoderSetParameter(
BrotliDecoderState* state, BrotliDecoderParameter param, uint32_t value);
/**
* Adds LZ77 prefix dictionary, adds or replaces built-in static dictionary and
* transforms.
*
* Attached dictionary ownership is not transferred.
* Data provided to this method should be kept accessible until
* decoding is finished and decoder instance is destroyed.
*
* @note Dictionaries can NOT be attached after actual decoding is started.
*
* @param state decoder instance
* @param type dictionary data format
* @param data_size length of memory region pointed by @p data
* @param data dictionary data in format corresponding to @p type
* @returns ::BROTLI_FALSE if dictionary is corrupted,
* or dictionary count limit is reached
* @returns ::BROTLI_TRUE if dictionary is accepted / attached
*/
BROTLI_DEC_API BROTLI_BOOL BrotliDecoderAttachDictionary(
BrotliDecoderState* state, BrotliSharedDictionaryType type,
size_t data_size, const uint8_t data[BROTLI_ARRAY_PARAM(data_size)]);
/**
* Creates an instance of ::BrotliDecoderState and initializes it.
*
* The instance can be used once for decoding and should then be destroyed with
* ::BrotliDecoderDestroyInstance, it cannot be reused for a new decoding
* session.
*
* @p alloc_func and @p free_func @b MUST be both zero or both non-zero. In the
* case they are both zero, default memory allocators are used. @p opaque is
* passed to @p alloc_func and @p free_func when they are called. @p free_func
* has to return without doing anything when asked to free a NULL pointer.
*
* @param alloc_func custom memory allocation function
* @param free_func custom memory free function
* @param opaque custom memory manager handle
* @returns @c 0 if instance can not be allocated or initialized
* @returns pointer to initialized ::BrotliDecoderState otherwise
*/
BROTLI_DEC_API BrotliDecoderState* BrotliDecoderCreateInstance(
brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque);
/**
* Deinitializes and frees ::BrotliDecoderState instance.
*
* @param state decoder instance to be cleaned up and deallocated
*/
BROTLI_DEC_API void BrotliDecoderDestroyInstance(BrotliDecoderState* state);
/**
* Performs one-shot memory-to-memory decompression.
*
* Decompresses the data in @p encoded_buffer into @p decoded_buffer, and sets
* @p *decoded_size to the decompressed length.
*
* @param encoded_size size of @p encoded_buffer
* @param encoded_buffer compressed data buffer with at least @p encoded_size
* addressable bytes
* @param[in, out] decoded_size @b in: size of @p decoded_buffer; \n
* @b out: length of decompressed data written to
* @p decoded_buffer
* @param decoded_buffer decompressed data destination buffer
* @returns ::BROTLI_DECODER_RESULT_ERROR if input is corrupted, memory
* allocation failed, or @p decoded_buffer is not large enough;
* @returns ::BROTLI_DECODER_RESULT_SUCCESS otherwise
*/
BROTLI_DEC_API BrotliDecoderResult BrotliDecoderDecompress(
size_t encoded_size,
const uint8_t encoded_buffer[BROTLI_ARRAY_PARAM(encoded_size)],
size_t* decoded_size,
uint8_t decoded_buffer[BROTLI_ARRAY_PARAM(*decoded_size)]);
/**
* Decompresses the input stream to the output stream.
*
* The values @p *available_in and @p *available_out must specify the number of
* bytes addressable at @p *next_in and @p *next_out respectively.
* When @p *available_out is @c 0, @p next_out is allowed to be @c NULL.
*
* After each call, @p *available_in will be decremented by the amount of input
* bytes consumed, and the @p *next_in pointer will be incremented by that
* amount. Similarly, @p *available_out will be decremented by the amount of
* output bytes written, and the @p *next_out pointer will be incremented by
* that amount.
*
* @p total_out, if it is not a null-pointer, will be set to the number
* of bytes decompressed since the last @p state initialization.
*
* @note Input is never overconsumed, so @p next_in and @p available_in could be
* passed to the next consumer after decoding is complete.
*
* @param state decoder instance
* @param[in, out] available_in @b in: amount of available input; \n
* @b out: amount of unused input
* @param[in, out] next_in pointer to the next compressed byte
* @param[in, out] available_out @b in: length of output buffer; \n
* @b out: remaining size of output buffer
* @param[in, out] next_out output buffer cursor;
* can be @c NULL if @p available_out is @c 0
* @param[out] total_out number of bytes decompressed so far; can be @c NULL
* @returns ::BROTLI_DECODER_RESULT_ERROR if input is corrupted, memory
* allocation failed, arguments were invalid, etc.;
* use ::BrotliDecoderGetErrorCode to get detailed error code
* @returns ::BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT decoding is blocked until
* more input data is provided
* @returns ::BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT decoding is blocked until
* more output space is provided
* @returns ::BROTLI_DECODER_RESULT_SUCCESS decoding is finished, no more
* input might be consumed and no more output will be produced
*/
BROTLI_DEC_API BrotliDecoderResult BrotliDecoderDecompressStream(
BrotliDecoderState* state, size_t* available_in, const uint8_t** next_in,
size_t* available_out, uint8_t** next_out, size_t* total_out);
/**
* Checks if decoder has more output.
*
* @param state decoder instance
* @returns ::BROTLI_TRUE, if decoder has some unconsumed output
* @returns ::BROTLI_FALSE otherwise
*/
BROTLI_DEC_API BROTLI_BOOL BrotliDecoderHasMoreOutput(
const BrotliDecoderState* state);
/**
* Acquires pointer to internal output buffer.
*
* This method is used to make language bindings easier and more efficient:
* -# push data to ::BrotliDecoderDecompressStream,
* until ::BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT is reported
* -# use ::BrotliDecoderTakeOutput to peek bytes and copy to language-specific
* entity
*
* Also this could be useful if there is an output stream that is able to
* consume all the provided data (e.g. when data is saved to file system).
*
* @attention After every call to ::BrotliDecoderTakeOutput @p *size bytes of
* output are considered consumed for all consecutive calls to the
* instance methods; returned pointer becomes invalidated as well.
*
* @note Decoder output is not guaranteed to be contiguous. This means that
* after the size-unrestricted call to ::BrotliDecoderTakeOutput,
* immediate next call to ::BrotliDecoderTakeOutput may return more data.
*
* @param state decoder instance
* @param[in, out] size @b in: number of bytes caller is ready to take, @c 0 if
* any amount could be handled; \n
* @b out: amount of data pointed by returned pointer and
* considered consumed; \n
* out value is never greater than in value, unless it is @c 0
* @returns pointer to output data
*/
BROTLI_DEC_API const uint8_t* BrotliDecoderTakeOutput(
BrotliDecoderState* state, size_t* size);
/**
* Checks if instance has already consumed input.
*
* Instance that returns ::BROTLI_FALSE is considered "fresh" and could be
* reused.
*
* @param state decoder instance
* @returns ::BROTLI_TRUE if decoder has already used some input bytes
* @returns ::BROTLI_FALSE otherwise
*/
BROTLI_DEC_API BROTLI_BOOL BrotliDecoderIsUsed(const BrotliDecoderState* state);
/**
* Checks if decoder instance reached the final state.
*
* @param state decoder instance
* @returns ::BROTLI_TRUE if decoder is in a state where it reached the end of
* the input and produced all of the output
* @returns ::BROTLI_FALSE otherwise
*/
BROTLI_DEC_API BROTLI_BOOL BrotliDecoderIsFinished(
const BrotliDecoderState* state);
/**
* Acquires a detailed error code.
*
* Should be used only after ::BrotliDecoderDecompressStream returns
* ::BROTLI_DECODER_RESULT_ERROR.
*
* See also ::BrotliDecoderErrorString
*
* @param state decoder instance
* @returns last saved error code
*/
BROTLI_DEC_API BrotliDecoderErrorCode BrotliDecoderGetErrorCode(
const BrotliDecoderState* state);
/**
* Converts error code to a c-string.
*/
BROTLI_DEC_API const char* BrotliDecoderErrorString(BrotliDecoderErrorCode c);
/**
* Gets a decoder library version.
*
* Look at BROTLI_MAKE_HEX_VERSION for more information.
*/
BROTLI_DEC_API uint32_t BrotliDecoderVersion(void);
/**
* Callback to fire on metadata block start.
*
* After this callback is fired, if @p size is not @c 0, it is followed by
* ::brotli_decoder_metadata_chunk_func as more metadata block contents become
* accessible.
*
* @param opaque callback handle
* @param size size of metadata block
*/
typedef void (*brotli_decoder_metadata_start_func)(void* opaque, size_t size);
/**
* Callback to fire on metadata block chunk becomes available.
*
* This function can be invoked multiple times per metadata block; block should
* be considered finished when sum of @p size matches the announced metadata
* block size. Chunks contents pointed by @p data are transient and shouln not
* be accessed after leaving the callback.
*
* @param opaque callback handle
* @param data pointer to metadata contents
* @param size size of metadata block chunk, at least @c 1
*/
typedef void (*brotli_decoder_metadata_chunk_func)(void* opaque,
const uint8_t* data,
size_t size);
/**
* Sets callback for receiving metadata blocks.
*
* @param state decoder instance
* @param start_func callback on metadata block start
* @param chunk_func callback on metadata block chunk
* @param opaque callback handle
*/
BROTLI_DEC_API void BrotliDecoderSetMetadataCallbacks(
BrotliDecoderState* state,
brotli_decoder_metadata_start_func start_func,
brotli_decoder_metadata_chunk_func chunk_func, void* opaque);
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */
#endif
#endif /* BROTLI_DEC_DECODE_H_ */