From 240d3a0cbdc46e4ed08d1015a2d4f1ca52bbdd55 Mon Sep 17 00:00:00 2001 From: Arne Schwabe Date: Fri, 3 May 2013 10:20:54 +0200 Subject: Add snappy library. In preparation for upcoming snappy support of OpenVPN --- snappy/snappy-c.h | 138 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 138 insertions(+) create mode 100644 snappy/snappy-c.h (limited to 'snappy/snappy-c.h') diff --git a/snappy/snappy-c.h b/snappy/snappy-c.h new file mode 100644 index 00000000..c6c2a860 --- /dev/null +++ b/snappy/snappy-c.h @@ -0,0 +1,138 @@ +/* + * Copyright 2011 Martin Gieseking . + * + * 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 + +/* + * 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". + * + * 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, + * 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. + * + * 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, + * 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_ */ -- cgit v1.2.3