redis_study/src/rdb.h
2020-09-05 12:01:22 +08:00

165 lines
7.4 KiB
C

/*
* Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
* 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 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 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 __RDB_H
#define __RDB_H
#include <stdio.h>
#include "rio.h"
/* TBD: include only necessary headers. */
#include "server.h"
/* The current RDB version. When the format changes in a way that is no longer
* backward compatible this number gets incremented. */
#define RDB_VERSION 9
/* Defines related to the dump file format. To store 32 bits lengths for short
* keys requires a lot of space, so we check the most significant 2 bits of
* the first byte to interpreter the length:
*
* 00|XXXXXX => if the two MSB are 00 the len is the 6 bits of this byte
* 01|XXXXXX XXXXXXXX => 01, the len is 14 byes, 6 bits + 8 bits of next byte
* 10|000000 [32 bit integer] => A full 32 bit len in net byte order will follow
* 10|000001 [64 bit integer] => A full 64 bit len in net byte order will follow
* 11|OBKIND this means: specially encoded object will follow. The six bits
* number specify the kind of object that follows.
* See the RDB_ENC_* defines.
*
* Lengths up to 63 are stored using a single byte, most DB keys, and may
* values, will fit inside. */
#define RDB_6BITLEN 0
#define RDB_14BITLEN 1
#define RDB_32BITLEN 0x80
#define RDB_64BITLEN 0x81
#define RDB_ENCVAL 3
#define RDB_LENERR UINT64_MAX
/* When a length of a string object stored on disk has the first two bits
* set, the remaining six bits specify a special encoding for the object
* accordingly to the following defines: */
#define RDB_ENC_INT8 0 /* 8 bit signed integer */
#define RDB_ENC_INT16 1 /* 16 bit signed integer */
#define RDB_ENC_INT32 2 /* 32 bit signed integer */
#define RDB_ENC_LZF 3 /* string compressed with FASTLZ */
/* Map object types to RDB object types. Macros starting with OBJ_ are for
* memory storage and may change. Instead RDB types must be fixed because
* we store them on disk. */
#define RDB_TYPE_STRING 0
#define RDB_TYPE_LIST 1
#define RDB_TYPE_SET 2
#define RDB_TYPE_ZSET 3
#define RDB_TYPE_HASH 4
#define RDB_TYPE_ZSET_2 5 /* ZSET version 2 with doubles stored in binary. */
#define RDB_TYPE_MODULE 6
#define RDB_TYPE_MODULE_2 7 /* Module value with annotations for parsing without
the generating module being loaded. */
/* NOTE: WHEN ADDING NEW RDB TYPE, UPDATE rdbIsObjectType() BELOW */
/* Object types for encoded objects. */
#define RDB_TYPE_HASH_ZIPMAP 9
#define RDB_TYPE_LIST_ZIPLIST 10
#define RDB_TYPE_SET_INTSET 11
#define RDB_TYPE_ZSET_ZIPLIST 12
#define RDB_TYPE_HASH_ZIPLIST 13
#define RDB_TYPE_LIST_QUICKLIST 14
#define RDB_TYPE_STREAM_LISTPACKS 15
/* NOTE: WHEN ADDING NEW RDB TYPE, UPDATE rdbIsObjectType() BELOW */
/* Test if a type is an object type. */
#define rdbIsObjectType(t) ((t >= 0 && t <= 7) || (t >= 9 && t <= 15))
/* Special RDB opcodes (saved/loaded with rdbSaveType/rdbLoadType). */
#define RDB_OPCODE_MODULE_AUX 247 /* Module auxiliary data. */
#define RDB_OPCODE_IDLE 248 /* LRU idle time. */
#define RDB_OPCODE_FREQ 249 /* LFU frequency. */
#define RDB_OPCODE_AUX 250 /* RDB aux field. */
#define RDB_OPCODE_RESIZEDB 251 /* Hash table resize hint. */
#define RDB_OPCODE_EXPIRETIME_MS 252 /* Expire time in milliseconds. */
#define RDB_OPCODE_EXPIRETIME 253 /* Old expire time in seconds. */
#define RDB_OPCODE_SELECTDB 254 /* DB number of the following keys. */
#define RDB_OPCODE_EOF 255 /* End of the RDB file. */
/* Module serialized values sub opcodes */
#define RDB_MODULE_OPCODE_EOF 0 /* End of module value. */
#define RDB_MODULE_OPCODE_SINT 1 /* Signed integer. */
#define RDB_MODULE_OPCODE_UINT 2 /* Unsigned integer. */
#define RDB_MODULE_OPCODE_FLOAT 3 /* Float. */
#define RDB_MODULE_OPCODE_DOUBLE 4 /* Double. */
#define RDB_MODULE_OPCODE_STRING 5 /* String. */
/* rdbLoad...() functions flags. */
#define RDB_LOAD_NONE 0
#define RDB_LOAD_ENC (1<<0)
#define RDB_LOAD_PLAIN (1<<1)
#define RDB_LOAD_SDS (1<<2)
/* flags on the purpose of rdb save or load */
#define RDBFLAGS_NONE 0 /* No special RDB loading. */
#define RDBFLAGS_AOF_PREAMBLE (1<<0) /* Load/save the RDB as AOF preamble. */
#define RDBFLAGS_REPLICATION (1<<1) /* Load/save for SYNC. */
#define RDBFLAGS_ALLOW_DUP (1<<2) /* Allow duplicated keys when loading.*/
int rdbSaveType(rio *rdb, unsigned char type);
int rdbLoadType(rio *rdb);
int rdbSaveTime(rio *rdb, time_t t);
time_t rdbLoadTime(rio *rdb);
int rdbSaveLen(rio *rdb, uint64_t len);
int rdbSaveMillisecondTime(rio *rdb, long long t);
long long rdbLoadMillisecondTime(rio *rdb, int rdbver);
uint64_t rdbLoadLen(rio *rdb, int *isencoded);
int rdbLoadLenByRef(rio *rdb, int *isencoded, uint64_t *lenptr);
int rdbSaveObjectType(rio *rdb, robj *o);
int rdbLoadObjectType(rio *rdb);
int rdbLoad(char *filename, rdbSaveInfo *rsi, int rdbflags);
int rdbSaveBackground(char *filename, rdbSaveInfo *rsi);
int rdbSaveToSlavesSockets(rdbSaveInfo *rsi);
void rdbRemoveTempFile(pid_t childpid);
int rdbSave(char *filename, rdbSaveInfo *rsi);
ssize_t rdbSaveObject(rio *rdb, robj *o, robj *key);
size_t rdbSavedObjectLen(robj *o, robj *key);
robj *rdbLoadObject(int type, rio *rdb, sds key);
void backgroundSaveDoneHandler(int exitcode, int bysignal);
int rdbSaveKeyValuePair(rio *rdb, robj *key, robj *val, long long expiretime);
ssize_t rdbSaveSingleModuleAux(rio *rdb, int when, moduleType *mt);
robj *rdbLoadStringObject(rio *rdb);
ssize_t rdbSaveStringObject(rio *rdb, robj *obj);
ssize_t rdbSaveRawString(rio *rdb, unsigned char *s, size_t len);
void *rdbGenericLoadStringObject(rio *rdb, int flags, size_t *lenptr);
int rdbSaveBinaryDoubleValue(rio *rdb, double val);
int rdbLoadBinaryDoubleValue(rio *rdb, double *val);
int rdbSaveBinaryFloatValue(rio *rdb, float val);
int rdbLoadBinaryFloatValue(rio *rdb, float *val);
int rdbLoadRio(rio *rdb, int rdbflags, rdbSaveInfo *rsi);
int rdbSaveRio(rio *rdb, int *error, int rdbflags, rdbSaveInfo *rsi);
rdbSaveInfo *rdbPopulateSaveInfo(rdbSaveInfo *rsi);
#endif