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/* 
 * 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 THIRD_PARTY_SNAPPY_OPENSOURCE_SNAPPY_C_H_
#define THIRD_PARTY_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  /* THIRD_PARTY_SNAPPY_OPENSOURCE_SNAPPY_C_H_ */