172 lines
6.8 KiB
C
172 lines
6.8 KiB
C
/*
|
|
* Copyright (C) 2013-2015 Willy Tarreau <w@1wt.eu>
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining
|
|
* a copy of this software and associated documentation files (the
|
|
* "Software"), to deal in the Software without restriction, including
|
|
* without limitation the rights to use, copy, modify, merge, publish,
|
|
* distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to
|
|
* the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be
|
|
* included in all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
|
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
|
|
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
|
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
|
|
* OTHER DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
#ifndef _SLZ_H
|
|
#define _SLZ_H
|
|
|
|
#include <inttypes.h>
|
|
|
|
/* We have two macros UNALIGNED_LE_OK and UNALIGNED_FASTER. The latter indicates
|
|
* that using unaligned data is faster than a simple shift. On x86 32-bit at
|
|
* least it is not the case as the per-byte access is 30% faster. A core2-duo on
|
|
* x86_64 is 7% faster to read one byte + shifting by 8 than to read one word,
|
|
* but a core i5 is 7% faster doing the unaligned read, so we privilege more
|
|
* recent implementations here.
|
|
*/
|
|
#if defined(__x86_64__)
|
|
#define UNALIGNED_LE_OK
|
|
#define UNALIGNED_FASTER
|
|
#define USE_64BIT_QUEUE
|
|
#elif defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__)
|
|
#define UNALIGNED_LE_OK
|
|
//#define UNALIGNED_FASTER
|
|
#elif defined(__ARMEL__) && defined(__ARM_ARCH_7A__)
|
|
#define UNALIGNED_LE_OK
|
|
#define UNALIGNED_FASTER
|
|
#elif defined(__ARM_ARCH_8A) || defined(__ARM_FEATURE_UNALIGNED)
|
|
#define UNALIGNED_LE_OK
|
|
#define UNALIGNED_FASTER
|
|
#endif
|
|
|
|
/* Log2 of the size of the hash table used for the references table. */
|
|
#define HASH_BITS 13
|
|
|
|
enum slz_state {
|
|
SLZ_ST_INIT, /* stream initialized */
|
|
SLZ_ST_EOB, /* header or end of block already sent */
|
|
SLZ_ST_FIXED, /* inside a fixed huffman sequence */
|
|
SLZ_ST_LAST, /* last block, BFINAL sent */
|
|
SLZ_ST_DONE, /* BFINAL+EOB sent BFINAL */
|
|
SLZ_ST_END /* end sent (BFINAL, EOB, CRC + len) */
|
|
};
|
|
|
|
enum {
|
|
SLZ_FMT_GZIP, /* RFC1952: gzip envelope and crc32 for CRC */
|
|
SLZ_FMT_ZLIB, /* RFC1950: zlib envelope and adler-32 for CRC */
|
|
SLZ_FMT_DEFLATE, /* RFC1951: raw deflate, and no crc */
|
|
};
|
|
|
|
struct slz_stream {
|
|
#ifdef USE_64BIT_QUEUE
|
|
uint64_t queue; /* last pending bits, LSB first */
|
|
#else
|
|
uint32_t queue; /* last pending bits, LSB first */
|
|
#endif
|
|
uint32_t qbits; /* number of bits in queue, < 8 on 32-bit, < 32 on 64-bit */
|
|
unsigned char *outbuf; /* set by encode() */
|
|
uint16_t state; /* one of slz_state */
|
|
uint8_t level:1; /* 0 = no compression, 1 = compression */
|
|
uint8_t format:2; /* SLZ_FMT_* */
|
|
uint8_t unused1; /* unused for now */
|
|
uint32_t crc32;
|
|
uint32_t ilen;
|
|
};
|
|
|
|
/* Functions specific to rfc1951 (deflate) */
|
|
long slz_rfc1951_encode(struct slz_stream *strm, unsigned char *out, const unsigned char *in, long ilen, int more);
|
|
int slz_rfc1951_init(struct slz_stream *strm, int level);
|
|
int slz_rfc1951_finish(struct slz_stream *strm, unsigned char *buf);
|
|
|
|
/* Functions specific to rfc1952 (gzip) */
|
|
uint32_t slz_crc32_by1(uint32_t crc, const unsigned char *buf, int len);
|
|
uint32_t slz_crc32_by4(uint32_t crc, const unsigned char *buf, int len);
|
|
long slz_rfc1952_encode(struct slz_stream *strm, unsigned char *out, const unsigned char *in, long ilen, int more);
|
|
int slz_rfc1952_send_header(struct slz_stream *strm, unsigned char *buf);
|
|
int slz_rfc1952_init(struct slz_stream *strm, int level);
|
|
int slz_rfc1952_finish(struct slz_stream *strm, unsigned char *buf);
|
|
|
|
/* Functions specific to rfc1950 (zlib) */
|
|
uint32_t slz_adler32_by1(uint32_t crc, const unsigned char *buf, int len);
|
|
uint32_t slz_adler32_block(uint32_t crc, const unsigned char *buf, long len);
|
|
long slz_rfc1950_encode(struct slz_stream *strm, unsigned char *out, const unsigned char *in, long ilen, int more);
|
|
int slz_rfc1950_send_header(struct slz_stream *strm, unsigned char *buf);
|
|
int slz_rfc1950_init(struct slz_stream *strm, int level);
|
|
int slz_rfc1950_finish(struct slz_stream *strm, unsigned char *buf);
|
|
|
|
/* generic functions */
|
|
|
|
/* Initializes stream <strm>. It will configure the stream to use format
|
|
* <format> for the data, which must be one of SLZ_FMT_*. The compression level
|
|
* passed in <level> is set. This value can only be 0 (no compression) or 1
|
|
* (compression) and other values will lead to unpredictable behaviour. The
|
|
* function should always return 0.
|
|
*/
|
|
static inline int slz_init(struct slz_stream *strm, int level, int format)
|
|
{
|
|
int ret;
|
|
|
|
if (format == SLZ_FMT_GZIP)
|
|
ret = slz_rfc1952_init(strm, level);
|
|
else if (format == SLZ_FMT_ZLIB)
|
|
ret = slz_rfc1950_init(strm, level);
|
|
else { /* deflate for anything else */
|
|
ret = slz_rfc1951_init(strm, level);
|
|
strm->format = format;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* Encodes the block according to the format used by the stream. This means
|
|
* that the CRC of the input block may be computed according to the CRC32 or
|
|
* adler-32 algorithms. The number of output bytes is returned.
|
|
*/
|
|
static inline long slz_encode(struct slz_stream *strm, void *out,
|
|
const void *in, long ilen, int more)
|
|
{
|
|
long ret;
|
|
|
|
if (strm->format == SLZ_FMT_GZIP)
|
|
ret = slz_rfc1952_encode(strm, (unsigned char *) out, (const unsigned char *) in, ilen, more);
|
|
else if (strm->format == SLZ_FMT_ZLIB)
|
|
ret = slz_rfc1950_encode(strm, (unsigned char *) out, (const unsigned char *) in, ilen, more);
|
|
else /* deflate for other ones */
|
|
ret = slz_rfc1951_encode(strm, (unsigned char *) out, (const unsigned char *) in, ilen, more);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Flushes pending bits and sends the trailer for stream <strm> into buffer
|
|
* <buf> if needed. When it's done, the stream state is updated to SLZ_ST_END.
|
|
* It returns the number of bytes emitted. The trailer consists in flushing the
|
|
* possibly pending bits from the queue (up to 24 bits), rounding to the next
|
|
* byte, then 4 bytes for the CRC when doing zlib/gzip, then another 4 bytes
|
|
* for the input length for gzip. That may about to 4+4+4 = 12 bytes, that the
|
|
* caller must ensure are available before calling the function.
|
|
*/
|
|
static inline int slz_finish(struct slz_stream *strm, void *buf)
|
|
{
|
|
int ret;
|
|
|
|
if (strm->format == SLZ_FMT_GZIP)
|
|
ret = slz_rfc1952_finish(strm, (unsigned char *) buf);
|
|
else if (strm->format == SLZ_FMT_ZLIB)
|
|
ret = slz_rfc1950_finish(strm, (unsigned char *) buf);
|
|
else /* deflate for other ones */
|
|
ret = slz_rfc1951_finish(strm, (unsigned char *) buf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#endif
|