/*
* Copyright 2011 Martin Gieseking <martin.gieseking@uos.de>.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Plain C interface (a wrapper around the C++ implementation).
*/
#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_
#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_
#ifdef __cplusplus
extern "C" {
#endif
#include <stddef.h>
/*
* Return values; see the documentation for each function to know
* what each can return.
*/
typedef enum {
SNAPPY_OK = 0,
SNAPPY_INVALID_INPUT = 1,
SNAPPY_BUFFER_TOO_SMALL = 2
} snappy_status;
/*
* Takes the data stored in "input[0..input_length-1]" and stores
* it in the array pointed to by "compressed".
*
* <compressed_length> signals the space available in "compressed".
* If it is not at least equal to "snappy_max_compressed_length(input_length)",
* SNAPPY_BUFFER_TOO_SMALL is returned. After successful compression,
* <compressed_length> contains the true length of the compressed output,
* and SNAPPY_OK is returned.
*
* Example:
* size_t output_length = snappy_max_compressed_length(input_length);
* char* output = (char*)malloc(output_length);
* if (snappy_compress(input, input_length, output, &output_length)
* == SNAPPY_OK) {
* ... Process(output, output_length) ...
* }
* free(output);
*/
snappy_status snappy_compress(const char* input,
size_t input_length,
char* compressed,
size_t* compressed_length);
/*
* Given data in "compressed[0..compressed_length-1]" generated by
* calling the snappy_compress routine, this routine stores
* the uncompressed data to
* uncompressed[0..uncompressed_length-1].
* Returns failure (a value not equal to SNAPPY_OK) if the message
* is corrupted and could not be decrypted.
*
* <uncompressed_length> signals the space available in "uncompressed".
* If it is not at least equal to the value returned by
* snappy_uncompressed_length for this stream, SNAPPY_BUFFER_TOO_SMALL
* is returned. After successful decompression, <uncompressed_length>
* contains the true length of the decompressed output.
*
* Example:
* size_t output_length;
* if (snappy_uncompressed_length(input, input_length, &output_length)
* != SNAPPY_OK) {
* ... fail ...
* }
* char* output = (char*)malloc(output_length);
* if (snappy_uncompress(input, input_length, output, &output_length)
* == SNAPPY_OK) {
* ... Process(output, output_length) ...
* }
* free(output);
*/
snappy_status snappy_uncompress(const char* compressed,
size_t compressed_length,
char* uncompressed,
size_t* uncompressed_length);
/*
* Returns the maximal size of the compressed representation of
* input data that is "source_length" bytes in length.
*/
size_t snappy_max_compressed_length(size_t source_length);
/*
* REQUIRES: "compressed[]" was produced by snappy_compress()
* Returns SNAPPY_OK and stores the length of the uncompressed data in
* *result normally. Returns SNAPPY_INVALID_INPUT on parsing error.
* This operation takes O(1) time.
*/
snappy_status snappy_uncompressed_length(const char* compressed,
size_t compressed_length,
size_t* result);
/*
* Check if the contents of "compressed[]" can be uncompressed successfully.
* Does not return the uncompressed data; if so, returns SNAPPY_OK,
* or if not, returns SNAPPY_INVALID_INPUT.
* Takes time proportional to compressed_length, but is usually at least a
* factor of four faster than actual decompression.
*/
snappy_status snappy_validate_compressed_buffer(const char* compressed,
size_t compressed_length);
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_ */