FastSort/ext/htslib/htscodecs/htscodecs/pack.h

87 lines
3.2 KiB
C

/*
* Copyright (c) 2019 Genome Research Ltd.
* Author(s): James Bonfield
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. Neither the names Genome Research Ltd and Wellcome Trust Sanger
* Institute 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 GENOME RESEARCH LTD 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 GENOME RESEARCH
* LTD 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.
*/
#ifndef HTS_PACK_H
#define HTS_PACK_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* Packs multiple symbols into a single byte if the total alphabet of symbols
* used is <= 16. Each new symbol takes up 1, 2, 4 or 8 bits, or 0 if the
* alphabet used is 1 (constant).
*
* If successful, out_meta/out_meta_len are set to hold the mapping table
* to be used during decompression.
*
* Returns the packed buffer on success with new length in out_len,
* NULL of failure
*/
uint8_t *hts_pack(uint8_t *data, int64_t len,
uint8_t *out_meta, int *out_meta_len, uint64_t *out_len);
/*
* Unpacks the meta-data portions of the hts_pack algorithm.
* This consists of the count of symbols and their values.
*
* The "map" array is filled out with the used symbols.
* "nsym" is set to contain the number of symbols per byte;
* 0, 1, 2, 4 or 8.
*
* Returns number of bytes of data[] consumed on success,
* zero on failure.
*/
uint8_t hts_unpack_meta(uint8_t *data, uint32_t data_len,
uint64_t udata_len, uint8_t *map, int *nsym);
/*
* Unpacks a packed data steam (given the unpacked meta-data).
*
* "map" is the pack map, mapping 0->n to the expanded symbols.
* The "out" buffer must be preallocated by the caller to be the correct
* size. For error checking purposes, out_len is set to the size of
* this buffer.
*
* Returns uncompressed data (out) on success,
* NULL on failure.
*/
uint8_t *hts_unpack(uint8_t *data, int64_t len, uint8_t *out, uint64_t out_len, int nsym, uint8_t *map);
#ifdef __cplusplus
}
#endif
#endif /* HTS_PACK_H */