File Content: decode.h /* 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/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..-18 codes are reserved */ \ \ 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); /** * 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_VERSION for more information. */ BROTLI_DEC_API uint32_t BrotliDecoderVersion(void); #if defined(__cplusplus) || defined(c_plusplus) } /* extern "C" */ #endif #endif /* BROTLI_DEC_DECODE_H_ */ Submit