diff options
| author | byte2016 <[email protected]> | 2018-06-12 19:55:38 +0800 |
|---|---|---|
| committer | byte2016 <[email protected]> | 2018-06-12 19:55:38 +0800 |
| commit | 76f2c13d7c27d7419af79ea0bdc7ab7717b6935b (patch) | |
| tree | aa2ca741501d40990b892d504a1cc3b7defe57aa /src/quicklist.h | |
Diffstat (limited to 'src/quicklist.h')
| -rw-r--r-- | src/quicklist.h | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/src/quicklist.h b/src/quicklist.h new file mode 100644 index 0000000..8f38759 --- /dev/null +++ b/src/quicklist.h @@ -0,0 +1,169 @@ +/* quicklist.h - A generic doubly linked quicklist implementation + * + * Copyright (c) 2014, Matt Stancliff <[email protected]> + * All rights reserved. + * + * 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 quicklist of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this quicklist of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Redis 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. + */ + +#ifndef __QUICKLIST_H__ +#define __QUICKLIST_H__ + +/* Node, quicklist, and Iterator are the only data structures used currently. */ + +/* quicklistNode is a 32 byte struct describing a ziplist for a quicklist. + * We use bit fields keep the quicklistNode at 32 bytes. + * count: 16 bits, max 65536 (max zl bytes is 65k, so max count actually < 32k). + * encoding: 2 bits, RAW=1, LZF=2. + * container: 2 bits, NONE=1, ZIPLIST=2. + * recompress: 1 bit, bool, true if node is temporarry decompressed for usage. + * attempted_compress: 1 bit, boolean, used for verifying during testing. + * extra: 12 bits, free for future use; pads out the remainder of 32 bits */ +typedef struct quicklistNode { + struct quicklistNode *prev; + struct quicklistNode *next; + unsigned char *zl; + unsigned int sz; /* ziplist size in bytes */ + unsigned int count : 16; /* count of items in ziplist */ + unsigned int encoding : 2; /* RAW==1 or LZF==2 */ + unsigned int container : 2; /* NONE==1 or ZIPLIST==2 */ + unsigned int recompress : 1; /* was this node previous compressed? */ + unsigned int attempted_compress : 1; /* node can't compress; too small */ + unsigned int extra : 10; /* more bits to steal for future usage */ +} quicklistNode; + +/* quicklistLZF is a 4+N byte struct holding 'sz' followed by 'compressed'. + * 'sz' is byte length of 'compressed' field. + * 'compressed' is LZF data with total (compressed) length 'sz' + * NOTE: uncompressed length is stored in quicklistNode->sz. + * When quicklistNode->zl is compressed, node->zl points to a quicklistLZF */ +typedef struct quicklistLZF { + unsigned int sz; /* LZF size in bytes*/ + char compressed[]; +} quicklistLZF; + +/* quicklist is a 32 byte struct (on 64-bit systems) describing a quicklist. + * 'count' is the number of total entries. + * 'len' is the number of quicklist nodes. + * 'compress' is: -1 if compression disabled, otherwise it's the number + * of quicklistNodes to leave uncompressed at ends of quicklist. + * 'fill' is the user-requested (or default) fill factor. */ +typedef struct quicklist { + quicklistNode *head; + quicklistNode *tail; + unsigned long count; /* total count of all entries in all ziplists */ + unsigned int len; /* number of quicklistNodes */ + int fill : 16; /* fill factor for individual nodes */ + unsigned int compress : 16; /* depth of end nodes not to compress;0=off */ +} quicklist; + +typedef struct quicklistIter { + const quicklist *quicklist; + quicklistNode *current; + unsigned char *zi; + long offset; /* offset in current ziplist */ + int direction; +} quicklistIter; + +typedef struct quicklistEntry { + const quicklist *quicklist; + quicklistNode *node; + unsigned char *zi; + unsigned char *value; + long long longval; + unsigned int sz; + int offset; +} quicklistEntry; + +#define QUICKLIST_HEAD 0 +#define QUICKLIST_TAIL -1 + +/* quicklist node encodings */ +#define QUICKLIST_NODE_ENCODING_RAW 1 +#define QUICKLIST_NODE_ENCODING_LZF 2 + +/* quicklist compression disable */ +#define QUICKLIST_NOCOMPRESS 0 + +/* quicklist container formats */ +#define QUICKLIST_NODE_CONTAINER_NONE 1 +#define QUICKLIST_NODE_CONTAINER_ZIPLIST 2 + +#define quicklistNodeIsCompressed(node) \ + ((node)->encoding == QUICKLIST_NODE_ENCODING_LZF) + +/* Prototypes */ +quicklist *quicklistCreate(void); +quicklist *quicklistNew(int fill, int compress); +void quicklistSetCompressDepth(quicklist *quicklist, int depth); +void quicklistSetFill(quicklist *quicklist, int fill); +void quicklistSetOptions(quicklist *quicklist, int fill, int depth); +void quicklistRelease(quicklist *quicklist); +int quicklistPushHead(quicklist *quicklist, void *value, const size_t sz); +int quicklistPushTail(quicklist *quicklist, void *value, const size_t sz); +void quicklistPush(quicklist *quicklist, void *value, const size_t sz, + int where); +void quicklistAppendZiplist(quicklist *quicklist, unsigned char *zl); +quicklist *quicklistAppendValuesFromZiplist(quicklist *quicklist, + unsigned char *zl); +quicklist *quicklistCreateFromZiplist(int fill, int compress, + unsigned char *zl); +void quicklistInsertAfter(quicklist *quicklist, quicklistEntry *node, + void *value, const size_t sz); +void quicklistInsertBefore(quicklist *quicklist, quicklistEntry *node, + void *value, const size_t sz); +void quicklistDelEntry(quicklistIter *iter, quicklistEntry *entry); +int quicklistReplaceAtIndex(quicklist *quicklist, long index, void *data, + int sz); +int quicklistDelRange(quicklist *quicklist, const long start, const long stop); +quicklistIter *quicklistGetIterator(const quicklist *quicklist, int direction); +quicklistIter *quicklistGetIteratorAtIdx(const quicklist *quicklist, + int direction, const long long idx); +int quicklistNext(quicklistIter *iter, quicklistEntry *node); +void quicklistReleaseIterator(quicklistIter *iter); +quicklist *quicklistDup(quicklist *orig); +int quicklistIndex(const quicklist *quicklist, const long long index, + quicklistEntry *entry); +void quicklistRewind(quicklist *quicklist, quicklistIter *li); +void quicklistRewindTail(quicklist *quicklist, quicklistIter *li); +void quicklistRotate(quicklist *quicklist); +int quicklistPopCustom(quicklist *quicklist, int where, unsigned char **data, + unsigned int *sz, long long *sval, + void *(*saver)(unsigned char *data, unsigned int sz)); +int quicklistPop(quicklist *quicklist, int where, unsigned char **data, + unsigned int *sz, long long *slong); +unsigned int quicklistCount(const quicklist *ql); +int quicklistCompare(unsigned char *p1, unsigned char *p2, int p2_len); +size_t quicklistGetLzf(const quicklistNode *node, void **data); + +#ifdef REDIS_TEST +int quicklistTest(int argc, char *argv[]); +#endif + +/* Directions for iterators */ +#define AL_START_HEAD 0 +#define AL_START_TAIL 1 + +#endif /* __QUICKLIST_H__ */ |
