/*
* 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.
*/
#include "server.h"
#include "lzf.h" /* LZF compression library */
#include "zipmap.h"
#include "endianconv.h"
#include "stream.h"
#include <math.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <sys/param.h>
#define rdbExitReportCorruptRDB(...) rdbCheckThenExit(__LINE__,__VA_ARGS__)
extern int rdbCheckMode;
void rdbCheckError(const char *fmt, ...);
void rdbCheckSetError(const char *fmt, ...);
void rdbCheckThenExit(int linenum, char *reason, ...) {
va_list ap;
char msg[1024];
int len;
len = snprintf(msg,sizeof(msg),
"Internal error in RDB reading function at rdb.c:%d -> ", linenum);
va_start(ap,reason);
vsnprintf(msg+len,sizeof(msg)-len,reason,ap);
va_end(ap);
if (!rdbCheckMode) {
serverLog(LL_WARNING, "%s", msg);
char *argv[2] = {"",server.rdb_filename};
redis_check_rdb_main(2,argv,NULL);
} else {
rdbCheckError("%s",msg);
}
exit(1);
}
static int rdbWriteRaw(rio *rdb, void *p, size_t len) {
if (rdb && rioWrite(rdb,p,len) == 0)
return -1;
return len;
}
/* This is just a wrapper for the low level function rioRead() that will
* automatically abort if it is not possible to read the specified amount
* of bytes. */
void rdbLoadRaw(rio *rdb, void *buf, uint64_t len) {
if (rioRead(rdb,buf,len) == 0) {
rdbExitReportCorruptRDB(
"Impossible to read %llu bytes in rdbLoadRaw()",
(unsigned long long) len);
return; /* Not reached. */
}
}
int rdbSaveType(rio *rdb, unsigned char type) {
return rdbWriteRaw(rdb,&type,1);
}
/* Load a "type" in RDB format, that is a one byte unsigned integer.
* This function is not only used to load object types, but also special
* "types" like the end-of-file type, the EXPIRE type, and so forth. */
int rdbLoadType(rio *rdb) {
unsigned char type;
if (rioRead(rdb,&type,1) == 0) return -1;
return type;
}
time_t rdbLoadTime(rio *rdb) {
int32_t t32;
rdbLoadRaw(rdb,&t32,4);
return (time_t)t32;
}
int rdbSaveMillisecondTime(rio *rdb, long long t) {
int64_t t64 = (int64_t) t;
return rdbWriteRaw(rdb,&t64,8);
}
long long rdbLoadMillisecondTime(rio *rdb) {
int64_t t64;
rdbLoadRaw(rdb,&t64,8);
return (long long)t64;
}
/* Saves an encoded length. The first two bits in the first byte are used to
* hold the encoding type. See the RDB_* definitions for more information
* on the types of encoding. */
int rdbSaveLen(rio *rdb, uint64_t len) {
unsigned char buf[2];
size_t nwritten;
if (len < (1<<6)) {
/* Save a 6 bit len */
buf[0] = (len&0xFF)|(RDB_6BITLEN<<6);
if (rdbWriteRaw(rdb,buf,1) == -1) return -1;
nwritten = 1;
} else if (len < (1<<14)) {
/* Save a 14 bit len */
buf[0] = ((len>>8)&0xFF)|(RDB_14BITLEN<<6);
buf[1] = len&0xFF;
if (rdbWriteRaw(rdb,buf,2) == -1) return -1;
nwritten = 2;
} else if (len <= UINT32_MAX) {
/* Save a 32 bit len */
buf[0] = RDB_32BITLEN;
if (rdbWriteRaw(rdb,buf,1) == -1) return -1;
uint32_t len32 = htonl(len);
if (rdbWriteRaw(rdb,&len32,4) == -1) return -1;
nwritten = 1+4;
} else {
/* Save a 64 bit len */
buf[0] = RDB_64BITLEN;
if (rdbWriteRaw(rdb,buf,1) == -1) return -1;
len = htonu64(len);
if (rdbWriteRaw(rdb,&len,8) == -1) return -1;
nwritten = 1+8;
}
return nwritten;
}
/* Load an encoded length. If the loaded length is a normal length as stored
* with rdbSaveLen(), the read length is set to '*lenptr'. If instead the
* loaded length describes a special encoding that follows, then '*isencoded'
* is set to 1 and the encoding format is stored at '*lenptr'.
*
* See the RDB_ENC_* definitions in rdb.h for more information on special
* encodings.
*
* The function returns -1 on error, 0 on success. */
int rdbLoadLenByRef(rio *rdb, int *isencoded, uint64_t *lenptr) {
unsigned char buf[2];
int type;
if (isencoded) *isencoded = 0;
if (rioRead(rdb,buf,1) == 0) return -1;
type = (buf[0]&0xC0)>>6;
if (type == RDB_ENCVAL) {
/* Read a 6 bit encoding type. */
if (isencoded) *isencoded = 1;
*lenptr = buf[0]&0x3F;
} else if (type == RDB_6BITLEN) {
/* Read a 6 bit len. */
*lenptr = buf[0]&0x3F;
} else if (type == RDB_14BITLEN) {
/* Read a 14 bit len. */
if (rioRead(rdb,buf+1,1) == 0) return -1;
*lenptr = ((buf[0]&0x3F)<<8)|buf[1];
} else if (buf[0] == RDB_32BITLEN) {
/* Read a 32 bit len. */
uint32_t len;
if (rioRead(rdb,&len,4) == 0) return -1;
*lenptr = ntohl(len);
} else if (buf[0] == RDB_64BITLEN) {
/* Read a 64 bit len. */
uint64_t len;
if (rioRead(rdb,&len,8) == 0) return -1;
*lenptr = ntohu64(len);
} else {
rdbExitReportCorruptRDB(
"Unknown length encoding %d in rdbLoadLen()",type);
return -1; /* Never reached. */
}
return 0;
}
/* This is like rdbLoadLenByRef() but directly returns the value read
* from the RDB stream, signaling an error by returning RDB_LENERR
* (since it is a too large count to be applicable in any Redis data
* structure). */
uint64_t rdbLoadLen(rio *rdb, int *isencoded) {
uint64_t len;
if (rdbLoadLenByRef(rdb,isencoded,&len) == -1) return RDB_LENERR;
return len;
}
/* Encodes the "value" argument as integer when it fits in the supported ranges
* for encoded types. If the function successfully encodes the integer, the
* representation is stored in the buffer pointer to by "enc" and the string
* length is returned. Otherwise 0 is returned. */
int rdbEncodeInteger(long long value, unsigned char *enc) {
if (value >= -(1<<7) && value <= (1<<7)-1) {
enc[0] = (RDB_ENCVAL<<6)|RDB_ENC_INT8;
enc[1] = value&0xFF;
return 2;
} else if (value >= -(1<<15) && value <= (1<<15)-1) {
enc[0] = (RDB_ENCVAL<<6)|RDB_ENC_INT16;
enc[1] = value&0xFF;
enc[2] = (value>>8)&0xFF;
return 3;
} else if (value >= -((long long)1<<31) && value <= ((long long)1<<31)-1) {
enc[0] = (RDB_ENCVAL<<6)|RDB_ENC_INT32;
enc[1] = value&0xFF;
enc[2] = (value>>8)&0xFF;
enc[3] = (value>>16)&0xFF;
enc[4] = (value>>24)&0xFF;
return 5;
} else {
return 0;
}
}
/* Loads an integer-encoded object with the specified encoding type "enctype".
* The returned value changes according to the flags, see
* rdbGenerincLoadStringObject() for more info. */
void *rdbLoadIntegerObject(rio *rdb, int enctype, int flags, size_t *lenptr) {
int plain = flags & RDB_LOAD_PLAIN;
int sds = flags & RDB_LOAD_SDS;
int encode = flags & RDB_LOAD_ENC;
unsigned char enc[4];
long long val;
if (enctype == RDB_ENC_INT8) {
if (rioRead(rdb,enc,1) == 0) return NULL;
val = (signed char)enc[0];
} else if (enctype == RDB_ENC_INT16) {
uint16_t v;
if (rioRead(rdb,enc,2) == 0) return NULL;
v = enc[0]|(enc[1]<<8);
val = (int16_t)v;
} else if (enctype == RDB_ENC_INT32) {
uint32_t v;
if (rioRead(rdb,enc,4) == 0) return NULL;
v = enc[0]|(enc[1]<<8)|(enc[2]<<16)|(enc[3]<<24);
val = (int32_t)v;
} else {
val = 0; /* anti-warning */
rdbExitReportCorruptRDB("Unknown RDB integer encoding type %d",enctype);
}
if (plain || sds) {
char buf[LONG_STR_SIZE], *p;
int len = ll2string(buf,sizeof(buf),val);
if (lenptr) *lenptr = len;
p = plain ? zmalloc(len) : sdsnewlen(SDS_NOINIT,len);
memcpy(p,buf,len);
return p;
} else if (encode) {
return createStringObjectFromLongLong(val);
} else {
return createObject(OBJ_STRING,sdsfromlonglong(val));
}
}
/* String objects in the form "2391" "-100" without any space and with a
* range of values that can fit in an 8, 16 or 32 bit signed value can be
* encoded as integers to save space */
int rdbTryIntegerEncoding(char *s, size_t len, unsigned char *enc) {
long long value;
char *endptr, buf[32];
/* Check if it's possible to encode this value as a number */
value = strtoll(s, &endptr, 10);
if (endptr[0] != '\0') return 0;
ll2string(buf,32,value);
/* If the number converted back into a string is not identical
* then it's not possible to encode the string as integer */
if (strlen(buf) != len || memcmp(buf,s,len)) return 0;
return rdbEncodeInteger(value,enc);
}
ssize_t rdbSaveLzfBlob(rio *rdb, void *data, size_t compress_len,
size_t original_len) {
unsigned char byte;
ssize_t n, nwritten = 0;
/* Data compressed! Let's save it on disk */
byte = (RDB_ENCVAL<<6)|RDB_ENC_LZF;
if ((n = rdbWriteRaw(rdb,&byte,1)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbSaveLen(rdb,compress_len)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbSaveLen(rdb,original_len)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbWriteRaw(rdb,data,compress_len)) == -1) goto writeerr;
nwritten += n;
return nwritten;
writeerr:
return -1;
}
ssize_t rdbSaveLzfStringObject(rio *rdb, unsigned char *s, size_t len) {
size_t comprlen, outlen;
void *out;
/* We require at least four bytes compression for this to be worth it */
if (len <= 4) return 0;
outlen = len-4;
if ((out = zmalloc(outlen+1)) == NULL) return 0;
comprlen = lzf_compress(s, len, out, outlen);
if (comprlen == 0) {
zfree(out);
return 0;
}
ssize_t nwritten = rdbSaveLzfBlob(rdb, out, comprlen, len);
zfree(out);
return nwritten;
}
/* Load an LZF compressed string in RDB format. The returned value
* changes according to 'flags'. For more info check the
* rdbGenericLoadStringObject() function. */
void *rdbLoadLzfStringObject(rio *rdb, int flags, size_t *lenptr) {
int plain = flags & RDB_LOAD_PLAIN;
int sds = flags & RDB_LOAD_SDS;
uint64_t len, clen;
unsigned char *c = NULL;
char *val = NULL;
if ((clen = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
if ((len = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
if ((c = zmalloc(clen)) == NULL) goto err;
/* Allocate our target according to the uncompressed size. */
if (plain) {
val = zmalloc(len);
} else {
val = sdsnewlen(SDS_NOINIT,len);
}
if (lenptr) *lenptr = len;
/* Load the compressed representation and uncompress it to target. */
if (rioRead(rdb,c,clen) == 0) goto err;
if (lzf_decompress(c,clen,val,len) == 0) {
if (rdbCheckMode) rdbCheckSetError("Invalid LZF compressed string");
goto err;
}
zfree(c);
if (plain || sds) {
return val;
} else {
return createObject(OBJ_STRING,val);
}
err:
zfree(c);
if (plain)
zfree(val);
else
sdsfree(val);
return NULL;
}
/* Save a string object as [len][data] on disk. If the object is a string
* representation of an integer value we try to save it in a special form */
ssize_t rdbSaveRawString(rio *rdb, unsigned char *s, size_t len) {
int enclen;
ssize_t n, nwritten = 0;
/* Try integer encoding */
if (len <= 11) {
unsigned char buf[5];
if ((enclen = rdbTryIntegerEncoding((char*)s,len,buf)) > 0) {
if (rdbWriteRaw(rdb,buf,enclen) == -1) return -1;
return enclen;
}
}
/* Try LZF compression - under 20 bytes it's unable to compress even
* aaaaaaaaaaaaaaaaaa so skip it */
if (server.rdb_compression && len > 20) {
n = rdbSaveLzfStringObject(rdb,s,len);
if (n == -1) return -1;
if (n > 0) return n;
/* Return value of 0 means data can't be compressed, save the old way */
}
/* Store verbatim */
if ((n = rdbSaveLen(rdb,len)) == -1) return -1;
nwritten += n;
if (len > 0) {
if (rdbWriteRaw(rdb,s,len) == -1) return -1;
nwritten += len;
}
return nwritten;
}
/* Save a long long value as either an encoded string or a string. */
ssize_t rdbSaveLongLongAsStringObject(rio *rdb, long long value) {
unsigned char buf[32];
ssize_t n, nwritten = 0;
int enclen = rdbEncodeInteger(value,buf);
if (enclen > 0) {
return rdbWriteRaw(rdb,buf,enclen);
} else {
/* Encode as string */
enclen = ll2string((char*)buf,32,value);
serverAssert(enclen < 32);
if ((n = rdbSaveLen(rdb,enclen)) == -1) return -1;
nwritten += n;
if ((n = rdbWriteRaw(rdb,buf,enclen)) == -1) return -1;
nwritten += n;
}
return nwritten;
}
/* Like rdbSaveRawString() gets a Redis object instead. */
ssize_t rdbSaveStringObject(rio *rdb, robj *obj) {
/* Avoid to decode the object, then encode it again, if the
* object is already integer encoded. */
if (obj->encoding == OBJ_ENCODING_INT) {
return rdbSaveLongLongAsStringObject(rdb,(long)obj->ptr);
} else {
serverAssertWithInfo(NULL,obj,sdsEncodedObject(obj));
return rdbSaveRawString(rdb,obj->ptr,sdslen(obj->ptr));
}
}
/* Load a string object from an RDB file according to flags:
*
* RDB_LOAD_NONE (no flags): load an RDB object, unencoded.
* RDB_LOAD_ENC: If the returned type is a Redis object, try to
* encode it in a special way to be more memory
* efficient. When this flag is passed the function
* no longer guarantees that obj->ptr is an SDS string.
* RDB_LOAD_PLAIN: Return a plain string allocated with zmalloc()
* instead of a Redis object with an sds in it.
* RDB_LOAD_SDS: Return an SDS string instead of a Redis object.
*
* On I/O error NULL is returned.
*/
void *rdbGenericLoadStringObject(rio *rdb, int flags, size_t *lenptr) {
int encode = flags & RDB_LOAD_ENC;
int plain = flags & RDB_LOAD_PLAIN;
int sds = flags & RDB_LOAD_SDS;
int isencoded;
uint64_t len;
len = rdbLoadLen(rdb,&isencoded);
if (isencoded) {
switch(len) {
case RDB_ENC_INT8:
case RDB_ENC_INT16:
case RDB_ENC_INT32:
return rdbLoadIntegerObject(rdb,len,flags,lenptr);
case RDB_ENC_LZF:
return rdbLoadLzfStringObject(rdb,flags,lenptr);
default:
rdbExitReportCorruptRDB("Unknown RDB string encoding type %d",len);
}
}
if (len == RDB_LENERR) return NULL;
if (plain || sds) {
void *buf = plain ? zmalloc(len) : sdsnewlen(SDS_NOINIT,len);
if (lenptr) *lenptr = len;
if (len && rioRead(rdb,buf,len) == 0) {
if (plain)
zfree(buf);
else
sdsfree(buf);
return NULL;
}
return buf;
} else {
robj *o = encode ? createStringObject(SDS_NOINIT,len) :
createRawStringObject(SDS_NOINIT,len);
if (len && rioRead(rdb,o->ptr,len) == 0) {
decrRefCount(o);
return NULL;
}
return o;
}
}
robj *rdbLoadStringObject(rio *rdb) {
return rdbGenericLoadStringObject(rdb,RDB_LOAD_NONE,NULL);
}
robj *rdbLoadEncodedStringObject(rio *rdb) {
return rdbGenericLoadStringObject(rdb,RDB_LOAD_ENC,NULL);
}
/* Save a double value. Doubles are saved as strings prefixed by an unsigned
* 8 bit integer specifying the length of the representation.
* This 8 bit integer has special values in order to specify the following
* conditions:
* 253: not a number
* 254: + inf
* 255: - inf
*/
int rdbSaveDoubleValue(rio *rdb, double val) {
unsigned char buf[128];
int len;
if (isnan(val)) {
buf[0] = 253;
len = 1;
} else if (!isfinite(val)) {
len = 1;
buf[0] = (val < 0) ? 255 : 254;
} else {
#if (DBL_MANT_DIG >= 52) && (LLONG_MAX == 0x7fffffffffffffffLL)
/* Check if the float is in a safe range to be casted into a
* long long. We are assuming that long long is 64 bit here.
* Also we are assuming that there are no implementations around where
* double has precision < 52 bit.
*
* Under this assumptions we test if a double is inside an interval
* where casting to long long is safe. Then using two castings we
* make sure the decimal part is zero. If all this is true we use
* integer printing function that is much faster. */
double min = -4503599627370495; /* (2^52)-1 */
double max = 4503599627370496; /* -(2^52) */
if (val > min && val < max && val == ((double)((long long)val)))
ll2string((char*)buf+1,sizeof(buf)-1,(long long)val);
else
#endif
snprintf((char*)buf+1,sizeof(buf)-1,"%.17g",val);
buf[0] = strlen((char*)buf+1);
len = buf[0]+1;
}
return rdbWriteRaw(rdb,buf,len);
}
/* For information about double serialization check rdbSaveDoubleValue() */
int rdbLoadDoubleValue(rio *rdb, double *val) {
char buf[256];
unsigned char len;
if (rioRead(rdb,&len,1) == 0) return -1;
switch(len) {
case 255: *val = R_NegInf; return 0;
case 254: *val = R_PosInf; return 0;
case 253: *val = R_Nan; return 0;
default:
if (rioRead(rdb,buf,len) == 0) return -1;
buf[len] = '\0';
sscanf(buf, "%lg", val);
return 0;
}
}
/* Saves a double for RDB 8 or greater, where IE754 binary64 format is assumed.
* We just make sure the integer is always stored in little endian, otherwise
* the value is copied verbatim from memory to disk.
*
* Return -1 on error, the size of the serialized value on success. */
int rdbSaveBinaryDoubleValue(rio *rdb, double val) {
memrev64ifbe(&val);
return rdbWriteRaw(rdb,&val,sizeof(val));
}
/* Loads a double from RDB 8 or greater. See rdbSaveBinaryDoubleValue() for
* more info. On error -1 is returned, otherwise 0. */
int rdbLoadBinaryDoubleValue(rio *rdb, double *val) {
if (rioRead(rdb,val,sizeof(*val)) == 0) return -1;
memrev64ifbe(val);
return 0;
}
/* Like rdbSaveBinaryDoubleValue() but single precision. */
int rdbSaveBinaryFloatValue(rio *rdb, float val) {
memrev32ifbe(&val);
return rdbWriteRaw(rdb,&val,sizeof(val));
}
/* Like rdbLoadBinaryDoubleValue() but single precision. */
int rdbLoadBinaryFloatValue(rio *rdb, float *val) {
if (rioRead(rdb,val,sizeof(*val)) == 0) return -1;
memrev32ifbe(val);
return 0;
}
/* Save the object type of object "o". */
int rdbSaveObjectType(rio *rdb, robj *o) {
switch (o->type) {
case OBJ_STRING:
return rdbSaveType(rdb,RDB_TYPE_STRING);
case OBJ_LIST:
if (o->encoding == OBJ_ENCODING_QUICKLIST)
return rdbSaveType(rdb,RDB_TYPE_LIST_QUICKLIST);
else
serverPanic("Unknown list encoding");
case OBJ_SET:
if (o->encoding == OBJ_ENCODING_INTSET)
return rdbSaveType(rdb,RDB_TYPE_SET_INTSET);
else if (o->encoding == OBJ_ENCODING_HT)
return rdbSaveType(rdb,RDB_TYPE_SET);
else
serverPanic("Unknown set encoding");
case OBJ_ZSET:
if (o->encoding == OBJ_ENCODING_ZIPLIST)
return rdbSaveType(rdb,RDB_TYPE_ZSET_ZIPLIST);
else if (o->encoding == OBJ_ENCODING_SKIPLIST)
return rdbSaveType(rdb,RDB_TYPE_ZSET_2);
else
serverPanic("Unknown sorted set encoding");
case OBJ_HASH:
if (o->encoding == OBJ_ENCODING_ZIPLIST)
return rdbSaveType(rdb,RDB_TYPE_HASH_ZIPLIST);
else if (o->encoding == OBJ_ENCODING_HT)
return rdbSaveType(rdb,RDB_TYPE_HASH);
else
serverPanic("Unknown hash encoding");
case OBJ_STREAM:
return rdbSaveType(rdb,RDB_TYPE_STREAM_LISTPACKS);
case OBJ_MODULE:
return rdbSaveType(rdb,RDB_TYPE_MODULE_2);
default:
serverPanic("Unknown object type");
}
return -1; /* avoid warning */
}
/* Use rdbLoadType() to load a TYPE in RDB format, but returns -1 if the
* type is not specifically a valid Object Type. */
int rdbLoadObjectType(rio *rdb) {
int type;
if ((type = rdbLoadType(rdb)) == -1) return -1;
if (!rdbIsObjectType(type)) return -1;
return type;
}
/* This helper function serializes a consumer group Pending Entries List (PEL)
* into the RDB file. The 'nacks' argument tells the function if also persist
* the informations about the not acknowledged message, or if to persist
* just the IDs: this is useful because for the global consumer group PEL
* we serialized the NACKs as well, but when serializing the local consumer
* PELs we just add the ID, that will be resolved inside the global PEL to
* put a reference to the same structure. */
ssize_t rdbSaveStreamPEL(rio *rdb, rax *pel, int nacks) {
ssize_t n, nwritten = 0;
/* Number of entries in the PEL. */
if ((n = rdbSaveLen(rdb,raxSize(pel))) == -1) return -1;
nwritten += n;
/* Save each entry. */
raxIterator ri;
raxStart(&ri,pel);
raxSeek(&ri,"^",NULL,0);
while(raxNext(&ri)) {
/* We store IDs in raw form as 128 big big endian numbers, like
* they are inside the radix tree key. */
if ((n = rdbWriteRaw(rdb,ri.key,sizeof(streamID))) == -1) return -1;
nwritten += n;
if (nacks) {
streamNACK *nack = ri.data;
if ((n = rdbSaveMillisecondTime(rdb,nack->delivery_time)) == -1)
return -1;
nwritten += n;
if ((n = rdbSaveLen(rdb,nack->delivery_count)) == -1) return -1;
nwritten += n;
/* We don't save the consumer name: we'll save the pending IDs
* for each consumer in the consumer PEL, and resolve the consumer
* at loading time. */
}
}
raxStop(&ri);
return nwritten;
}
/* Serialize the consumers of a stream consumer group into the RDB. Helper
* function for the stream data type serialization. What we do here is to
* persist the consumer metadata, and it's PEL, for each consumer. */
size_t rdbSaveStreamConsumers(rio *rdb, streamCG *cg) {
ssize_t n, nwritten = 0;
/* Number of consumers in this consumer group. */
if ((n = rdbSaveLen(rdb,raxSize(cg->consumers))) == -1) return -1;
nwritten += n;
/* Save each consumer. */
raxIterator ri;
raxStart(&ri,cg->consumers);
raxSeek(&ri,"^",NULL,0);
while(raxNext(&ri)) {
streamConsumer *consumer = ri.data;
/* Consumer name. */
if ((n = rdbSaveRawString(rdb,ri.key,ri.key_len)) == -1) return -1;
nwritten += n;
/* Last seen time. */
if ((n = rdbSaveMillisecondTime(rdb,consumer->seen_time)) == -1)
return -1;
nwritten += n;
/* Consumer PEL, without the ACKs (see last parameter of the function
* passed with value of 0), at loading time we'll lookup the ID
* in the consumer group global PEL and will put a reference in the
* consumer local PEL. */
if ((n = rdbSaveStreamPEL(rdb,consumer->pel,0)) == -1)
return -1;
nwritten += n;
}
raxStop(&ri);
return nwritten;
}
/* Save a Redis object.
* Returns -1 on error, number of bytes written on success. */
ssize_t rdbSaveObject(rio *rdb, robj *o) {
ssize_t n = 0, nwritten = 0;
if (o->type == OBJ_STRING) {
/* Save a string value */
if ((n = rdbSaveStringObject(rdb,o)) == -1) return -1;
nwritten += n;
} else if (o->type == OBJ_LIST) {
/* Save a list value */
if (o->encoding == OBJ_ENCODING_QUICKLIST) {
quicklist *ql = o->ptr;
quicklistNode *node = ql->head;
if ((n = rdbSaveLen(rdb,ql->len)) == -1) return -1;
nwritten += n;
while(node) {
if (quicklistNodeIsCompressed(node)) {
void *data;
size_t compress_len = quicklistGetLzf(node, &data);
if ((n = rdbSaveLzfBlob(rdb,data,compress_len,node->sz)) == -1) return -1;
nwritten += n;
} else {
if ((n = rdbSaveRawString(rdb,node->zl,node->sz)) == -1) return -1;
nwritten += n;
}
node = node->next;
}
} else {
serverPanic("Unknown list encoding");
}
} else if (o->type == OBJ_SET) {
/* Save a set value */
if (o->encoding == OBJ_ENCODING_HT) {
dict *set = o->ptr;
dictIterator *di = dictGetIterator(set);
dictEntry *de;
if ((n = rdbSaveLen(rdb,dictSize(set))) == -1) return -1;
nwritten += n;
while((de = dictNext(di)) != NULL) {
sds ele = dictGetKey(de);
if ((n = rdbSaveRawString(rdb,(unsigned char*)ele,sdslen(ele)))
== -1) return -1;
nwritten += n;
}
dictReleaseIterator(di);
} else if (o->encoding == OBJ_ENCODING_INTSET) {
size_t l = intsetBlobLen((intset*)o->ptr);
if ((n = rdbSaveRawString(rdb,o->ptr,l)) == -1) return -1;
nwritten += n;
} else {
serverPanic("Unknown set encoding");
}
} else if (o->type == OBJ_ZSET) {
/* Save a sorted set value */
if (o->encoding == OBJ_ENCODING_ZIPLIST) {
size_t l = ziplistBlobLen((unsigned char*)o->ptr);
if ((n = rdbSaveRawString(rdb,o->ptr,l)) == -1) return -1;
nwritten += n;
} else if (o->encoding == OBJ_ENCODING_SKIPLIST) {
zset *zs = o->ptr;
zskiplist *zsl = zs->zsl;
if ((n = rdbSaveLen(rdb,zsl->length)) == -1) return -1;
nwritten += n;
/* We save the skiplist elements from the greatest to the smallest
* (that's trivial since the elements are already ordered in the
* skiplist): this improves the load process, since the next loaded
* element will always be the smaller, so adding to the skiplist
* will always immediately stop at the head, making the insertion
* O(1) instead of O(log(N)). */
zskiplistNode *zn = zsl->tail;
while (zn != NULL) {
if ((n = rdbSaveRawString(rdb,
(unsigned char*)zn->ele,sdslen(zn->ele))) == -1)
{
return -1;
}
nwritten += n;
if ((n = rdbSaveBinaryDoubleValue(rdb,zn->score)) == -1)
return -1;
nwritten += n;
zn = zn->backward;
}
} else {
serverPanic("Unknown sorted set encoding");
}
} else if (o->type == OBJ_HASH) {
/* Save a hash value */
if (o->encoding == OBJ_ENCODING_ZIPLIST) {
size_t l = ziplistBlobLen((unsigned char*)o->ptr);
if ((n = rdbSaveRawString(rdb,o->ptr,l)) == -1) return -1;
nwritten += n;
} else if (o->encoding == OBJ_ENCODING_HT) {
dictIterator *di = dictGetIterator(o->ptr);
dictEntry *de;
if ((n = rdbSaveLen(rdb,dictSize((dict*)o->ptr))) == -1) return -1;
nwritten += n;
while((de = dictNext(di)) != NULL) {
sds field = dictGetKey(de);
sds value = dictGetVal(de);
if ((n = rdbSaveRawString(rdb,(unsigned char*)field,
sdslen(field))) == -1) return -1;
nwritten += n;
if ((n = rdbSaveRawString(rdb,(unsigned char*)value,
sdslen(value))) == -1) return -1;
nwritten += n;
}
dictReleaseIterator(di);
} else {
serverPanic("Unknown hash encoding");
}
} else if (o->type == OBJ_STREAM) {
/* Store how many listpacks we have inside the radix tree. */
stream *s = o->ptr;
rax *rax = s->rax;
if ((n = rdbSaveLen(rdb,raxSize(rax))) == -1) return -1;
nwritten += n;
/* Serialize all the listpacks inside the radix tree as they are,
* when loading back, we'll use the first entry of each listpack
* to insert it back into the radix tree. */
raxIterator ri;
raxStart(&ri,rax);
raxSeek(&ri,"^",NULL,0);
while (raxNext(&ri)) {
unsigned char *lp = ri.data;
size_t lp_bytes = lpBytes(lp);
if ((n = rdbSaveRawString(rdb,ri.key,ri.key_len)) == -1) return -1;
nwritten += n;
if ((n = rdbSaveRawString(rdb,lp,lp_bytes)) == -1) return -1;
nwritten += n;
}
raxStop(&ri);
/* Save the number of elements inside the stream. We cannot obtain
* this easily later, since our macro nodes should be checked for
* number of items: not a great CPU / space tradeoff. */
if ((n = rdbSaveLen(rdb,s->length)) == -1) return -1;
nwritten += n;
/* Save the last entry ID. */
if ((n = rdbSaveLen(rdb,s->last_id.ms)) == -1) return -1;
nwritten += n;
if ((n = rdbSaveLen(rdb,s->last_id.seq)) == -1) return -1;
nwritten += n;
/* The consumer groups and their clients are part of the stream
* type, so serialize every consumer group. */
/* Save the number of groups. */
size_t num_cgroups = s->cgroups ? raxSize(s->cgroups) : 0;
if ((n = rdbSaveLen(rdb,num_cgroups)) == -1) return -1;
nwritten += n;
if (num_cgroups) {
/* Serialize each consumer group. */
raxStart(&ri,s->cgroups);
raxSeek(&ri,"^",NULL,0);
while(raxNext(&ri)) {
streamCG *cg = ri.data;
/* Save the group name. */
if ((n = rdbSaveRawString(rdb,ri.key,ri.key_len)) == -1)
return -1;
nwritten += n;
/* Last ID. */
if ((n = rdbSaveLen(rdb,cg->last_id.ms)) == -1) return -1;
nwritten += n;
if ((n = rdbSaveLen(rdb,cg->last_id.seq)) == -1) return -1;
nwritten += n;
/* Save the global PEL. */
if ((n = rdbSaveStreamPEL(rdb,cg->pel,1)) == -1) return -1;
nwritten += n;
/* Save the consumers of this group. */
if ((n = rdbSaveStreamConsumers(rdb,cg)) == -1) return -1;
nwritten += n;
}
raxStop(&ri);
}
} else if (o->type == OBJ_MODULE) {
/* Save a module-specific value. */
RedisModuleIO io;
moduleValue *mv = o->ptr;
moduleType *mt = mv->type;
moduleInitIOContext(io,mt,rdb);
/* Write the "module" identifier as prefix, so that we'll be able
* to call the right module during loading. */
int retval = rdbSaveLen(rdb,mt->id);
if (retval == -1) return -1;
io.bytes += retval;
/* Then write the module-specific representation + EOF marker. */
mt->rdb_save(&io,mv->value);
retval = rdbSaveLen(rdb,RDB_MODULE_OPCODE_EOF);
if (retval == -1) return -1;
io.bytes += retval;
if (io.ctx) {
moduleFreeContext(io.ctx);
zfree(io.ctx);
}
return io.error ? -1 : (ssize_t)io.bytes;
} else {
serverPanic("Unknown object type");
}
return nwritten;
}
/* Return the length the object will have on disk if saved with
* the rdbSaveObject() function. Currently we use a trick to get
* this length with very little changes to the code. In the future
* we could switch to a faster solution. */
size_t rdbSavedObjectLen(robj *o) {
ssize_t len = rdbSaveObject(NULL,o);
serverAssertWithInfo(NULL,o,len != -1);
return len;
}
/* Save a key-value pair, with expire time, type, key, value.
* On error -1 is returned.
* On success if the key was actually saved 1 is returned, otherwise 0
* is returned (the key was already expired). */
int rdbSaveKeyValuePair(rio *rdb, robj *key, robj *val,
long long expiretime, long long now)
{
int savelru = server.maxmemory_policy & MAXMEMORY_FLAG_LRU;
int savelfu = server.maxmemory_policy & MAXMEMORY_FLAG_LFU;
/* Save the expire time */
if (expiretime != -1) {
/* If this key is already expired skip it */
if (expiretime < now) return 0;
if (rdbSaveType(rdb,RDB_OPCODE_EXPIRETIME_MS) == -1) return -1;
if (rdbSaveMillisecondTime(rdb,expiretime) == -1) return -1;
}
/* Save the LRU info. */
if (savelru) {
int idletime = estimateObjectIdleTime(val);
idletime /= 1000; /* Using seconds is enough and requires less space.*/
if (rdbSaveType(rdb,RDB_OPCODE_IDLE) == -1) return -1;
if (rdbSaveLen(rdb,idletime) == -1) return -1;
}
/* Save the LFU info. */
if (savelfu) {
uint8_t buf[1];
buf[0] = LFUDecrAndReturn(val);
/* We can encode this in exactly two bytes: the opcode and an 8
* bit counter, since the frequency is logarithmic with a 0-255 range.
* Note that we do not store the halving time because to reset it
* a single time when loading does not affect the frequency much. */
if (rdbSaveType(rdb,RDB_OPCODE_FREQ) == -1) return -1;
if (rdbWriteRaw(rdb,buf,1) == -1) return -1;
}
/* Save type, key, value */
if (rdbSaveObjectType(rdb,val) == -1) return -1;
if (rdbSaveStringObject(rdb,key) == -1) return -1;
if (rdbSaveObject(rdb,val) == -1) return -1;
return 1;
}
/* Save an AUX field. */
ssize_t rdbSaveAuxField(rio *rdb, void *key, size_t keylen, void *val, size_t vallen) {
ssize_t ret, len = 0;
if ((ret = rdbSaveType(rdb,RDB_OPCODE_AUX)) == -1) return -1;
len += ret;
if ((ret = rdbSaveRawString(rdb,key,keylen)) == -1) return -1;
len += ret;
if ((ret = rdbSaveRawString(rdb,val,vallen)) == -1) return -1;
len += ret;
return len;
}
/* Wrapper for rdbSaveAuxField() used when key/val length can be obtained
* with strlen(). */
ssize_t rdbSaveAuxFieldStrStr(rio *rdb, char *key, char *val) {
return rdbSaveAuxField(rdb,key,strlen(key),val,strlen(val));
}
/* Wrapper for strlen(key) + integer type (up to long long range). */
ssize_t rdbSaveAuxFieldStrInt(rio *rdb, char *key, long long val) {
char buf[LONG_STR_SIZE];
int vlen = ll2string(buf,sizeof(buf),val);
return rdbSaveAuxField(rdb,key,strlen(key),buf,vlen);
}
/* Save a few default AUX fields with information about the RDB generated. */
int rdbSaveInfoAuxFields(rio *rdb, int flags, rdbSaveInfo *rsi) {
int redis_bits = (sizeof(void*) == 8) ? 64 : 32;
int aof_preamble = (flags & RDB_SAVE_AOF_PREAMBLE) != 0;
/* Add a few fields about the state when the RDB was created. */
if (rdbSaveAuxFieldStrStr(rdb,"redis-ver",REDIS_VERSION) == -1) return -1;
if (rdbSaveAuxFieldStrInt(rdb,"redis-bits",redis_bits) == -1) return -1;
if (rdbSaveAuxFieldStrInt(rdb,"ctime",time(NULL)) == -1) return -1;
if (rdbSaveAuxFieldStrInt(rdb,"used-mem",zmalloc_used_memory()) == -1) return -1;
/* Handle saving options that generate aux fields. */
if (rsi) {
if (rdbSaveAuxFieldStrInt(rdb,"repl-stream-db",rsi->repl_stream_db)
== -1) return -1;
if (rdbSaveAuxFieldStrStr(rdb,"repl-id",server.replid)
== -1) return -1;
if (rdbSaveAuxFieldStrInt(rdb,"repl-offset",server.master_repl_offset)
== -1) return -1;
}
if (rdbSaveAuxFieldStrInt(rdb,"aof-preamble",aof_preamble) == -1) return -1;
return 1;
}
/* Produces a dump of the database in RDB format sending it to the specified
* Redis I/O channel. On success C_OK is returned, otherwise C_ERR
* is returned and part of the output, or all the output, can be
* missing because of I/O errors.
*
* When the function returns C_ERR and if 'error' is not NULL, the
* integer pointed by 'error' is set to the value of errno just after the I/O
* error. */
int rdbSaveRio(rio *rdb, int *error, int flags, rdbSaveInfo *rsi) {
dictIterator *di = NULL;
dictEntry *de;
char magic[10];
int j;
long long now = mstime();
uint64_t cksum;
size_t processed = 0;
if (server.rdb_checksum)
rdb->update_cksum = rioGenericUpdateChecksum;
snprintf(magic,sizeof(magic),"REDIS%04d",RDB_VERSION);
if (rdbWriteRaw(rdb,magic,9) == -1) goto werr;
if (rdbSaveInfoAuxFields(rdb,flags,rsi) == -1) goto werr;
for (j = 0; j < server.dbnum; j++) {
redisDb *db = server.db+j;
dict *d = db->dict;
if (dictSize(d) == 0) continue;
di = dictGetSafeIterator(d);
if (!di) return C_ERR;
/* Write the SELECT DB opcode */
if (rdbSaveType(rdb,RDB_OPCODE_SELECTDB) == -1) goto werr;
if (rdbSaveLen(rdb,j) == -1) goto werr;
/* Write the RESIZE DB opcode. We trim the size to UINT32_MAX, which
* is currently the largest type we are able to represent in RDB sizes.
* However this does not limit the actual size of the DB to load since
* these sizes are just hints to resize the hash tables. */
uint32_t db_size, expires_size;
db_size = (dictSize(db->dict) <= UINT32_MAX) ?
dictSize(db->dict) :
UINT32_MAX;
expires_size = (dictSize(db->expires) <= UINT32_MAX) ?
dictSize(db->expires) :
UINT32_MAX;
if (rdbSaveType(rdb,RDB_OPCODE_RESIZEDB) == -1) goto werr;
if (rdbSaveLen(rdb,db_size) == -1) goto werr;
if (rdbSaveLen(rdb,expires_size) == -1) goto werr;
/* Iterate this DB writing every entry */
while((de = dictNext(di)) != NULL) {
sds keystr = dictGetKey(de);
robj key, *o = dictGetVal(de);
long long expire;
initStaticStringObject(key,keystr);
expire = getExpire(db,&key);
if (rdbSaveKeyValuePair(rdb,&key,o,expire,now) == -1) goto werr;
/* When this RDB is produced as part of an AOF rewrite, move
* accumulated diff from parent to child while rewriting in
* order to have a smaller final write. */
if (flags & RDB_SAVE_AOF_PREAMBLE &&
rdb->processed_bytes > processed+AOF_READ_DIFF_INTERVAL_BYTES)
{
processed = rdb->processed_bytes;
aofReadDiffFromParent();
}
}
dictReleaseIterator(di);
}
di = NULL; /* So that we don't release it again on error. */
/* If we are storing the replication information on disk, persist
* the script cache as well: on successful PSYNC after a restart, we need
* to be able to process any EVALSHA inside the replication backlog the
* master will send us. */
if (rsi && dictSize(server.lua_scripts)) {
di = dictGetIterator(server.lua_scripts);
while((de = dictNext(di)) != NULL) {
robj *body = dictGetVal(de);
if (rdbSaveAuxField(rdb,"lua",3,body->ptr,sdslen(body->ptr)) == -1)
goto werr;
}
dictReleaseIterator(di);
}
/* EOF opcode */
if (rdbSaveType(rdb,RDB_OPCODE_EOF) == -1) goto werr;
/* CRC64 checksum. It will be zero if checksum computation is disabled, the
* loading code skips the check in this case. */
cksum = rdb->cksum;
memrev64ifbe(&cksum);
if (rioWrite(rdb,&cksum,8) == 0) goto werr;
return C_OK;
werr:
if (error) *error = errno;
if (di) dictReleaseIterator(di);
return C_ERR;
}
/* This is just a wrapper to rdbSaveRio() that additionally adds a prefix
* and a suffix to the generated RDB dump. The prefix is:
*
* $EOF:<40 bytes unguessable hex string>\r\n
*
* While the suffix is the 40 bytes hex string we announced in the prefix.
* This way processes receiving the payload can understand when it ends
* without doing any processing of the content. */
int rdbSaveRioWithEOFMark(rio *rdb, int *error, rdbSaveInfo *rsi) {
char eofmark[RDB_EOF_MARK_SIZE];
getRandomHexChars(eofmark,RDB_EOF_MARK_SIZE);
if (error) *error = 0;
if (rioWrite(rdb,"$EOF:",5) == 0) goto werr;
if (rioWrite(rdb,eofmark,RDB_EOF_MARK_SIZE) == 0) goto werr;
if (rioWrite(rdb,"\r\n",2) == 0) goto werr;
if (rdbSaveRio(rdb,error,RDB_SAVE_NONE,rsi) == C_ERR) goto werr;
if (rioWrite(rdb,eofmark,RDB_EOF_MARK_SIZE) == 0) goto werr;
return C_OK;
werr: /* Write error. */
/* Set 'error' only if not already set by rdbSaveRio() call. */
if (error && *error == 0) *error = errno;
return C_ERR;
}
/* Save the DB on disk. Return C_ERR on error, C_OK on success. */
int rdbSave(char *filename, rdbSaveInfo *rsi) {
char tmpfile[256];
char cwd[MAXPATHLEN]; /* Current working dir path for error messages. */
FILE *fp;
rio rdb;
int error = 0;
snprintf(tmpfile,256,"temp-%d.rdb", (int) getpid());
fp = fopen(tmpfile,"w");
if (!fp) {
char *cwdp = getcwd(cwd,MAXPATHLEN);
serverLog(LL_WARNING,
"Failed opening the RDB file %s (in server root dir %s) "
"for saving: %s",
filename,
cwdp ? cwdp : "unknown",
strerror(errno));
return C_ERR;
}
rioInitWithFile(&rdb,fp);
if (rdbSaveRio(&rdb,&error,RDB_SAVE_NONE,rsi) == C_ERR) {
errno = error;
goto werr;
}
/* Make sure data will not remain on the OS's output buffers */
if (fflush(fp) == EOF) goto werr;
if (fsync(fileno(fp)) == -1) goto werr;
if (fclose(fp) == EOF) goto werr;
/* Use RENAME to make sure the DB file is changed atomically only
* if the generate DB file is ok. */
if (rename(tmpfile,filename) == -1) {
char *cwdp = getcwd(cwd,MAXPATHLEN);
serverLog(LL_WARNING,
"Error moving temp DB file %s on the final "
"destination %s (in server root dir %s): %s",
tmpfile,
filename,
cwdp ? cwdp : "unknown",
strerror(errno));
unlink(tmpfile);
return C_ERR;
}
serverLog(LL_NOTICE,"DB saved on disk");
server.dirty = 0;
server.lastsave = time(NULL);
server.lastbgsave_status = C_OK;
return C_OK;
werr:
serverLog(LL_WARNING,"Write error saving DB on disk: %s", strerror(errno));
fclose(fp);
unlink(tmpfile);
return C_ERR;
}
int rdbSaveBackground(char *filename, rdbSaveInfo *rsi) {
pid_t childpid;
long long start;
if (server.aof_child_pid != -1 || server.rdb_child_pid != -1) return C_ERR;
server.dirty_before_bgsave = server.dirty;
server.lastbgsave_try = time(NULL);
openChildInfoPipe();
start = ustime();
if ((childpid = fork()) == 0) {
int retval;
/* Child */
closeListeningSockets(0);
redisSetProcTitle("redis-rdb-bgsave");
retval = rdbSave(filename,rsi);
if (retval == C_OK) {
size_t private_dirty = zmalloc_get_private_dirty(-1);
if (private_dirty) {
serverLog(LL_NOTICE,
"RDB: %zu MB of memory used by copy-on-write",
private_dirty/(1024*1024));
}
server.child_info_data.cow_size = private_dirty;
sendChildInfo(CHILD_INFO_TYPE_RDB);
}
exitFromChild((retval == C_OK) ? 0 : 1);
} else {
/* Parent */
server.stat_fork_time = ustime()-start;
server.stat_fork_rate = (double) zmalloc_used_memory() * 1000000 / server.stat_fork_time / (1024*1024*1024); /* GB per second. */
latencyAddSampleIfNeeded("fork",server.stat_fork_time/1000);
if (childpid == -1) {
closeChildInfoPipe();
server.lastbgsave_status = C_ERR;
serverLog(LL_WARNING,"Can't save in background: fork: %s",
strerror(errno));
return C_ERR;
}
serverLog(LL_NOTICE,"Background saving started by pid %d",childpid);
server.rdb_save_time_start = time(NULL);
server.rdb_child_pid = childpid;
server.rdb_child_type = RDB_CHILD_TYPE_DISK;
updateDictResizePolicy();
return C_OK;
}
return C_OK; /* unreached */
}
void rdbRemoveTempFile(pid_t childpid) {
char tmpfile[256];
snprintf(tmpfile,sizeof(tmpfile),"temp-%d.rdb", (int) childpid);
unlink(tmpfile);
}
/* This function is called by rdbLoadObject() when the code is in RDB-check
* mode and we find a module value of type 2 that can be parsed without
* the need of the actual module. The value is parsed for errors, finally
* a dummy redis object is returned just to conform to the API. */
robj *rdbLoadCheckModuleValue(rio *rdb, char *modulename) {
uint64_t opcode;
while((opcode = rdbLoadLen(rdb,NULL)) != RDB_MODULE_OPCODE_EOF) {
if (opcode == RDB_MODULE_OPCODE_SINT ||
opcode == RDB_MODULE_OPCODE_UINT)
{
uint64_t len;
if (rdbLoadLenByRef(rdb,NULL,&len) == -1) {
rdbExitReportCorruptRDB(
"Error reading integer from module %s value", modulename);
}
} else if (opcode == RDB_MODULE_OPCODE_STRING) {
robj *o = rdbGenericLoadStringObject(rdb,RDB_LOAD_NONE,NULL);
if (o == NULL) {
rdbExitReportCorruptRDB(
"Error reading string from module %s value", modulename);
}
decrRefCount(o);
} else if (opcode == RDB_MODULE_OPCODE_FLOAT) {
float val;
if (rdbLoadBinaryFloatValue(rdb,&val) == -1) {
rdbExitReportCorruptRDB(
"Error reading float from module %s value", modulename);
}
} else if (opcode == RDB_MODULE_OPCODE_DOUBLE) {
double val;
if (rdbLoadBinaryDoubleValue(rdb,&val) == -1) {
rdbExitReportCorruptRDB(
"Error reading double from module %s value", modulename);
}
}
}
return createStringObject("module-dummy-value",18);
}
/* Load a Redis object of the specified type from the specified file.
* On success a newly allocated object is returned, otherwise NULL. */
robj *rdbLoadObject(int rdbtype, rio *rdb) {
robj *o = NULL, *ele, *dec;
uint64_t len;
unsigned int i;
if (rdbtype == RDB_TYPE_STRING) {
/* Read string value */
if ((o = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
o = tryObjectEncoding(o);
} else if (rdbtype == RDB_TYPE_LIST) {
/* Read list value */
if ((len = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
o = createQuicklistObject();
quicklistSetOptions(o->ptr, server.list_max_ziplist_size,
server.list_compress_depth);
/* Load every single element of the list */
while(len--) {
if ((ele = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
dec = getDecodedObject(ele);
size_t len = sdslen(dec->ptr);
quicklistPushTail(o->ptr, dec->ptr, len);
decrRefCount(dec);
decrRefCount(ele);
}
} else if (rdbtype == RDB_TYPE_SET) {
/* Read Set value */
if ((len = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
/* Use a regular set when there are too many entries. */
if (len > server.set_max_intset_entries) {
o = createSetObject();
/* It's faster to expand the dict to the right size asap in order
* to avoid rehashing */
if (len > DICT_HT_INITIAL_SIZE)
dictExpand(o->ptr,len);
} else {
o = createIntsetObject();
}
/* Load every single element of the set */
for (i = 0; i < len; i++) {
long long llval;
sds sdsele;
if ((sdsele = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
if (o->encoding == OBJ_ENCODING_INTSET) {
/* Fetch integer value from element. */
if (isSdsRepresentableAsLongLong(sdsele,&llval) == C_OK) {
o->ptr = intsetAdd(o->ptr,llval,NULL);
} else {
setTypeConvert(o,OBJ_ENCODING_HT);
dictExpand(o->ptr,len);
}
}
/* This will also be called when the set was just converted
* to a regular hash table encoded set. */
if (o->encoding == OBJ_ENCODING_HT) {
dictAdd((dict*)o->ptr,sdsele,NULL);
} else {
sdsfree(sdsele);
}
}
} else if (rdbtype == RDB_TYPE_ZSET_2 || rdbtype == RDB_TYPE_ZSET) {
/* Read list/set value. */
uint64_t zsetlen;
size_t maxelelen = 0;
zset *zs;
if ((zsetlen = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
o = createZsetObject();
zs = o->ptr;
/* Load every single element of the sorted set. */
while(zsetlen--) {
sds sdsele;
double score;
zskiplistNode *znode;
if ((sdsele = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
if (rdbtype == RDB_TYPE_ZSET_2) {
if (rdbLoadBinaryDoubleValue(rdb,&score) == -1) return NULL;
} else {
if (rdbLoadDoubleValue(rdb,&score) == -1) return NULL;
}
/* Don't care about integer-encoded strings. */
if (sdslen(sdsele) > maxelelen) maxelelen = sdslen(sdsele);
znode = zslInsert(zs->zsl,score,sdsele);
dictAdd(zs->dict,sdsele,&znode->score);
}
/* Convert *after* loading, since sorted sets are not stored ordered. */
if (zsetLength(o) <= server.zset_max_ziplist_entries &&
maxelelen <= server.zset_max_ziplist_value)
zsetConvert(o,OBJ_ENCODING_ZIPLIST);
} else if (rdbtype == RDB_TYPE_HASH) {
uint64_t len;
int ret;
sds field, value;
len = rdbLoadLen(rdb, NULL);
if (len == RDB_LENERR) return NULL;
o = createHashObject();
/* Too many entries? Use a hash table. */
if (len > server.hash_max_ziplist_entries)
hashTypeConvert(o, OBJ_ENCODING_HT);
/* Load every field and value into the ziplist */
while (o->encoding == OBJ_ENCODING_ZIPLIST && len > 0) {
len--;
/* Load raw strings */
if ((field = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
if ((value = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
/* Add pair to ziplist */
o->ptr = ziplistPush(o->ptr, (unsigned char*)field,
sdslen(field), ZIPLIST_TAIL);
o->ptr = ziplistPush(o->ptr, (unsigned char*)value,
sdslen(value), ZIPLIST_TAIL);
/* Convert to hash table if size threshold is exceeded */
if (sdslen(field) > server.hash_max_ziplist_value ||
sdslen(value) > server.hash_max_ziplist_value)
{
sdsfree(field);
sdsfree(value);
hashTypeConvert(o, OBJ_ENCODING_HT);
break;
}
sdsfree(field);
sdsfree(value);
}
/* Load remaining fields and values into the hash table */
while (o->encoding == OBJ_ENCODING_HT && len > 0) {
len--;
/* Load encoded strings */
if ((field = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
if ((value = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL))
== NULL) return NULL;
/* Add pair to hash table */
ret = dictAdd((dict*)o->ptr, field, value);
if (ret == DICT_ERR) {
rdbExitReportCorruptRDB("Duplicate keys detected");
}
}
/* All pairs should be read by now */
serverAssert(len == 0);
} else if (rdbtype == RDB_TYPE_LIST_QUICKLIST) {
if ((len = rdbLoadLen(rdb,NULL)) == RDB_LENERR) return NULL;
o = createQuicklistObject();
quicklistSetOptions(o->ptr, server.list_max_ziplist_size,
server.list_compress_depth);
while (len--) {
unsigned char *zl =
rdbGenericLoadStringObject(rdb,RDB_LOAD_PLAIN,NULL);
if (zl == NULL) return NULL;
quicklistAppendZiplist(o->ptr, zl);
}
} else if (rdbtype == RDB_TYPE_HASH_ZIPMAP ||
rdbtype == RDB_TYPE_LIST_ZIPLIST ||
rdbtype == RDB_TYPE_SET_INTSET ||
rdbtype == RDB_TYPE_ZSET_ZIPLIST ||
rdbtype == RDB_TYPE_HASH_ZIPLIST)
{
unsigned char *encoded =
rdbGenericLoadStringObject(rdb,RDB_LOAD_PLAIN,NULL);
if (encoded == NULL) return NULL;
o = createObject(OBJ_STRING,encoded); /* Obj type fixed below. */
/* Fix the object encoding, and make sure to convert the encoded
* data type into the base type if accordingly to the current
* configuration there are too many elements in the encoded data
* type. Note that we only check the length and not max element
* size as this is an O(N) scan. Eventually everything will get
* converted. */
switch(rdbtype) {
case RDB_TYPE_HASH_ZIPMAP:
/* Convert to ziplist encoded hash. This must be deprecated
* when loading dumps created by Redis 2.4 gets deprecated. */
{
unsigned char *zl = ziplistNew();
unsigned char *zi = zipmapRewind(o->ptr);
unsigned char *fstr, *vstr;
unsigned int flen, vlen;
unsigned int maxlen = 0;
while ((zi = zipmapNext(zi, &fstr, &flen, &vstr, &vlen)) != NULL) {
if (flen > maxlen) maxlen = flen;
if (vlen > maxlen) maxlen = vlen;
zl = ziplistPush(zl, fstr, flen, ZIPLIST_TAIL);
zl = ziplistPush(zl, vstr, vlen, ZIPLIST_TAIL);
}
zfree(o->ptr);
o->ptr = zl;
o->type = OBJ_HASH;
o->encoding = OBJ_ENCODING_ZIPLIST;
if (hashTypeLength(o) > server.hash_max_ziplist_entries ||
maxlen > server.hash_max_ziplist_value)
{
hashTypeConvert(o, OBJ_ENCODING_HT);
}
}
break;
case RDB_TYPE_LIST_ZIPLIST:
o->type = OBJ_LIST;
o->encoding = OBJ_ENCODING_ZIPLIST;
listTypeConvert(o,OBJ_ENCODING_QUICKLIST);
break;
case RDB_TYPE_SET_INTSET:
o->type = OBJ_SET;
o->encoding = OBJ_ENCODING_INTSET;
if (intsetLen(o->ptr) > server.set_max_intset_entries)
setTypeConvert(o,OBJ_ENCODING_HT);
break;
case RDB_TYPE_ZSET_ZIPLIST:
o->type = OBJ_ZSET;
o->encoding = OBJ_ENCODING_ZIPLIST;
if (zsetLength(o) > server.zset_max_ziplist_entries)
zsetConvert(o,OBJ_ENCODING_SKIPLIST);
break;
case RDB_TYPE_HASH_ZIPLIST:
o->type = OBJ_HASH;
o->encoding = OBJ_ENCODING_ZIPLIST;
if (hashTypeLength(o) > server.hash_max_ziplist_entries)
hashTypeConvert(o, OBJ_ENCODING_HT);
break;
default:
rdbExitReportCorruptRDB("Unknown RDB encoding type %d",rdbtype);
break;
}
} else if (rdbtype == RDB_TYPE_STREAM_LISTPACKS) {
o = createStreamObject();
stream *s = o->ptr;
uint64_t listpacks = rdbLoadLen(rdb,NULL);
while(listpacks--) {
/* Get the master ID, the one we'll use as key of the radix tree
* node: the entries inside the listpack itself are delta-encoded
* relatively to this ID. */
sds nodekey = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL);
if (sdslen(nodekey) != sizeof(streamID)) {
rdbExitReportCorruptRDB("Stream node key entry is not the "
"size of a stream ID");
}
/* Load the listpack. */
unsigned char *lp =
rdbGenericLoadStringObject(rdb,RDB_LOAD_PLAIN,NULL);
if (lp == NULL) return NULL;
unsigned char *first = lpFirst(lp);
if (first == NULL) {
/* Serialized listpacks should never be empty, since on
* deletion we should remove the radix tree key if the
* resulting listpack is emtpy. */
rdbExitReportCorruptRDB("Empty listpack inside stream");
}
/* Insert the key in the radix tree. */
int retval = raxInsert(s->rax,
(unsigned char*)nodekey,sizeof(streamID),lp,NULL);
sdsfree(nodekey);
if (!retval)
rdbExitReportCorruptRDB("Listpack re-added with existing key");
}
/* Load total number of items inside the stream. */
s->length = rdbLoadLen(rdb,NULL);
/* Load the last entry ID. */
s->last_id.ms = rdbLoadLen(rdb,NULL);
s->last_id.seq = rdbLoadLen(rdb,NULL);
/* Consumer groups loading */
size_t cgroups_count = rdbLoadLen(rdb,NULL);
while(cgroups_count--) {
/* Get the consumer group name and ID. We can then create the
* consumer group ASAP and populate its structure as
* we read more data. */
streamID cg_id;
sds cgname = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL);
if (cgname == NULL) {
rdbExitReportCorruptRDB(
"Error reading the consumer group name from Stream");
}
cg_id.ms = rdbLoadLen(rdb,NULL);
cg_id.seq = rdbLoadLen(rdb,NULL);
streamCG *cgroup = streamCreateCG(s,cgname,sdslen(cgname),&cg_id);
if (cgroup == NULL)
rdbExitReportCorruptRDB("Duplicated consumer group name %s",
cgname);
sdsfree(cgname);
/* Load the global PEL for this consumer group, however we'll
* not yet populate the NACK structures with the message
* owner, since consumers for this group and their messages will
* be read as a next step. So for now leave them not resolved
* and later populate it. */
size_t pel_size = rdbLoadLen(rdb,NULL);
while(pel_size--) {
unsigned char rawid[sizeof(streamID)];
rdbLoadRaw(rdb,rawid,sizeof(rawid));
streamNACK *nack = streamCreateNACK(NULL);
nack->delivery_time = rdbLoadMillisecondTime(rdb);
nack->delivery_count = rdbLoadLen(rdb,NULL);
if (!raxInsert(cgroup->pel,rawid,sizeof(rawid),nack,NULL))
rdbExitReportCorruptRDB("Duplicated gobal PEL entry "
"loading stream consumer group");
}
/* Now that we loaded our global PEL, we need to load the
* consumers and their local PELs. */
size_t consumers_num = rdbLoadLen(rdb,NULL);
while(consumers_num--) {
sds cname = rdbGenericLoadStringObject(rdb,RDB_LOAD_SDS,NULL);
if (cname == NULL) {
rdbExitReportCorruptRDB(
"Error reading the consumer name from Stream group");
}
streamConsumer *consumer = streamLookupConsumer(cgroup,cname,
1);
sdsfree(cname);
consumer->seen_time = rdbLoadMillisecondTime(rdb);
/* Load the PEL about entries owned by this specific
* consumer. */
pel_size = rdbLoadLen(rdb,NULL);
while(pel_size--) {
unsigned char rawid[sizeof(streamID)];
rdbLoadRaw(rdb,rawid,sizeof(rawid));
streamNACK *nack = raxFind(cgroup->pel,rawid,sizeof(rawid));
if (nack == raxNotFound)
rdbExitReportCorruptRDB("Consumer entry not found in "
"group global PEL");
/* Set the NACK consumer, that was left to NULL when
* loading the global PEL. Then set the same shared
* NACK structure also in the consumer-specific PEL. */
nack->consumer = consumer;
if (!raxInsert(consumer->pel,rawid,sizeof(rawid),nack,NULL))
rdbExitReportCorruptRDB("Duplicated consumer PEL entry "
" loading a stream consumer "
"group");
}
}
}
} else if (rdbtype == RDB_TYPE_MODULE || rdbtype == RDB_TYPE_MODULE_2) {
uint64_t moduleid = rdbLoadLen(rdb,NULL);
moduleType *mt = moduleTypeLookupModuleByID(moduleid);
char name[10];
if (rdbCheckMode && rdbtype == RDB_TYPE_MODULE_2)
return rdbLoadCheckModuleValue(rdb,name);
if (mt == NULL) {
moduleTypeNameByID(name,moduleid);
serverLog(LL_WARNING,"The RDB file contains module data I can't load: no matching module '%s'", name);
exit(1);
}
RedisModuleIO io;
moduleInitIOContext(io,mt,rdb);
io.ver = (rdbtype == RDB_TYPE_MODULE) ? 1 : 2;
/* Call the rdb_load method of the module providing the 10 bit
* encoding version in the lower 10 bits of the module ID. */
void *ptr = mt->rdb_load(&io,moduleid&1023);
if (io.ctx) {
moduleFreeContext(io.ctx);
zfree(io.ctx);
}
/* Module v2 serialization has an EOF mark at the end. */
if (io.ver == 2) {
uint64_t eof = rdbLoadLen(rdb,NULL);
if (eof != RDB_MODULE_OPCODE_EOF) {
serverLog(LL_WARNING,"The RDB file contains module data for the module '%s' that is not terminated by the proper module value EOF marker", name);
exit(1);
}
}
if (ptr == NULL) {
moduleTypeNameByID(name,moduleid);
serverLog(LL_WARNING,"The RDB file contains module data for the module type '%s', that the responsible module is not able to load. Check for modules log above for additional clues.", name);
exit(1);
}
o = createModuleObject(mt,ptr);
} else {
rdbExitReportCorruptRDB("Unknown RDB encoding type %d",rdbtype);
}
return o;
}
/* Mark that we are loading in the global state and setup the fields
* needed to provide loading stats. */
void startLoading(FILE *fp) {
struct stat sb;
/* Load the DB */
server.loading = 1;
server.loading_start_time = time(NULL);
server.loading_loaded_bytes = 0;
if (fstat(fileno(fp), &sb) == -1) {
server.loading_total_bytes = 0;
} else {
server.loading_total_bytes = sb.st_size;
}
}
/* Refresh the loading progress info */
void loadingProgress(off_t pos) {
server.loading_loaded_bytes = pos;
if (server.stat_peak_memory < zmalloc_used_memory())
server.stat_peak_memory = zmalloc_used_memory();
}
/* Loading finished */
void stopLoading(void) {
server.loading = 0;
}
/* Track loading progress in order to serve client's from time to time
and if needed calculate rdb checksum */
void rdbLoadProgressCallback(rio *r, const void *buf, size_t len) {
if (server.rdb_checksum)
rioGenericUpdateChecksum(r, buf, len);
if (server.loading_process_events_interval_bytes &&
(r->processed_bytes + len)/server.loading_process_events_interval_bytes > r->processed_bytes/server.loading_process_events_interval_bytes)
{
/* The DB can take some non trivial amount of time to load. Update
* our cached time since it is used to create and update the last
* interaction time with clients and for other important things. */
updateCachedTime();
if (server.masterhost && server.repl_state == REPL_STATE_TRANSFER)
replicationSendNewlineToMaster();
loadingProgress(r->processed_bytes);
processEventsWhileBlocked();
}
}
/* Load an RDB file from the rio stream 'rdb'. On success C_OK is returned,
* otherwise C_ERR is returned and 'errno' is set accordingly. */
int rdbLoadRio(rio *rdb, rdbSaveInfo *rsi) {
uint64_t dbid;
int type, rdbver;
redisDb *db = server.db+0;
char buf[1024];
long long expiretime, now = mstime();
rdb->update_cksum = rdbLoadProgressCallback;
rdb->max_processing_chunk = server.loading_process_events_interval_bytes;
if (rioRead(rdb,buf,9) == 0) goto eoferr;
buf[9] = '\0';
if (memcmp(buf,"REDIS",5) != 0) {
serverLog(LL_WARNING,"Wrong signature trying to load DB from file");
errno = EINVAL;
return C_ERR;
}
rdbver = atoi(buf+5);
if (rdbver < 1 || rdbver > RDB_VERSION) {
serverLog(LL_WARNING,"Can't handle RDB format version %d",rdbver);
errno = EINVAL;
return C_ERR;
}
while(1) {
robj *key, *val;
expiretime = -1;
/* Read type. */
if ((type = rdbLoadType(rdb)) == -1) goto eoferr;
/* Handle special types. */
if (type == RDB_OPCODE_EXPIRETIME) {
/* EXPIRETIME: load an expire associated with the next key
* to load. Note that after loading an expire we need to
* load the actual type, and continue. */
expiretime = rdbLoadTime(rdb);
/* We read the time so we need to read the object type again. */
if ((type = rdbLoadType(rdb)) == -1) goto eoferr;
/* the EXPIRETIME opcode specifies time in seconds, so convert
* into milliseconds. */
expiretime *= 1000;
} else if (type == RDB_OPCODE_EXPIRETIME_MS) {
/* EXPIRETIME_MS: milliseconds precision expire times introduced
* with RDB v3. Like EXPIRETIME but no with more precision. */
expiretime = rdbLoadMillisecondTime(rdb);
/* We read the time so we need to read the object type again. */
if ((type = rdbLoadType(rdb)) == -1) goto eoferr;
} else if (type == RDB_OPCODE_EOF) {
/* EOF: End of file, exit the main loop. */
break;
} else if (type == RDB_OPCODE_SELECTDB) {
/* SELECTDB: Select the specified database. */
if ((dbid = rdbLoadLen(rdb,NULL)) == RDB_LENERR)
goto eoferr;
if (dbid >= (unsigned)server.dbnum) {
serverLog(LL_WARNING,
"FATAL: Data file was created with a Redis "
"server configured to handle more than %d "
"databases. Exiting\n", server.dbnum);
exit(1);
}
db = server.db+dbid;
continue; /* Read type again. */
} else if (type == RDB_OPCODE_RESIZEDB) {
/* RESIZEDB: Hint about the size of the keys in the currently
* selected data base, in order to avoid useless rehashing. */
uint64_t db_size, expires_size;
if ((db_size = rdbLoadLen(rdb,NULL)) == RDB_LENERR)
goto eoferr;
if ((expires_size = rdbLoadLen(rdb,NULL)) == RDB_LENERR)
goto eoferr;
dictExpand(db->dict,db_size);
dictExpand(db->expires,expires_size);
continue; /* Read type again. */
} else if (type == RDB_OPCODE_AUX) {
/* AUX: generic string-string fields. Use to add state to RDB
* which is backward compatible. Implementations of RDB loading
* are requierd to skip AUX fields they don't understand.
*
* An AUX field is composed of two strings: key and value. */
robj *auxkey, *auxval;
if ((auxkey = rdbLoadStringObject(rdb)) == NULL) goto eoferr;
if ((auxval = rdbLoadStringObject(rdb)) == NULL) goto eoferr;
if (((char*)auxkey->ptr)[0] == '%') {
/* All the fields with a name staring with '%' are considered
* information fields and are logged at startup with a log
* level of NOTICE. */
serverLog(LL_NOTICE,"RDB '%s': %s",
(char*)auxkey->ptr,
(char*)auxval->ptr);
} else if (!strcasecmp(auxkey->ptr,"repl-stream-db")) {
if (rsi) rsi->repl_stream_db = atoi(auxval->ptr);
} else if (!strcasecmp(auxkey->ptr,"repl-id")) {
if (rsi && sdslen(auxval->ptr) == CONFIG_RUN_ID_SIZE) {
memcpy(rsi->repl_id,auxval->ptr,CONFIG_RUN_ID_SIZE+1);
rsi->repl_id_is_set = 1;
}
} else if (!strcasecmp(auxkey->ptr,"repl-offset")) {
if (rsi) rsi->repl_offset = strtoll(auxval->ptr,NULL,10);
} else if (!strcasecmp(auxkey->ptr,"lua")) {
/* Load the script back in memory. */
if (luaCreateFunction(NULL,server.lua,auxval) == NULL) {
rdbExitReportCorruptRDB(
"Can't load Lua script from RDB file! "
"BODY: %s", auxval->ptr);
}
} else {
/* We ignore fields we don't understand, as by AUX field
* contract. */
serverLog(LL_DEBUG,"Unrecognized RDB AUX field: '%s'",
(char*)auxkey->ptr);
}
decrRefCount(auxkey);
decrRefCount(auxval);
continue; /* Read type again. */
}
/* Read key */
if ((key = rdbLoadStringObject(rdb)) == NULL) goto eoferr;
/* Read value */
if ((val = rdbLoadObject(type,rdb)) == NULL) goto eoferr;
/* Check if the key already expired. This function is used when loading
* an RDB file from disk, either at startup, or when an RDB was
* received from the master. In the latter case, the master is
* responsible for key expiry. If we would expire keys here, the
* snapshot taken by the master may not be reflected on the slave. */
if (server.masterhost == NULL && expiretime != -1 && expiretime < now) {
decrRefCount(key);
decrRefCount(val);
continue;
}
/* Add the new object in the hash table */
dbAdd(db,key,val);
/* Set the expire time if needed */
if (expiretime != -1) setExpire(NULL,db,key,expiretime);
decrRefCount(key);
}
/* Verify the checksum if RDB version is >= 5 */
if (rdbver >= 5 && server.rdb_checksum) {
uint64_t cksum, expected = rdb->cksum;
if (rioRead(rdb,&cksum,8) == 0) goto eoferr;
memrev64ifbe(&cksum);
if (cksum == 0) {
serverLog(LL_WARNING,"RDB file was saved with checksum disabled: no check performed.");
} else if (cksum != expected) {
serverLog(LL_WARNING,"Wrong RDB checksum. Aborting now.");
rdbExitReportCorruptRDB("RDB CRC error");
}
}
return C_OK;
eoferr: /* unexpected end of file is handled here with a fatal exit */
serverLog(LL_WARNING,"Short read or OOM loading DB. Unrecoverable error, aborting now.");
rdbExitReportCorruptRDB("Unexpected EOF reading RDB file");
return C_ERR; /* Just to avoid warning */
}
/* Like rdbLoadRio() but takes a filename instead of a rio stream. The
* filename is open for reading and a rio stream object created in order
* to do the actual loading. Moreover the ETA displayed in the INFO
* output is initialized and finalized.
*
* If you pass an 'rsi' structure initialied with RDB_SAVE_OPTION_INIT, the
* loading code will fiil the information fields in the structure. */
int rdbLoad(char *filename, rdbSaveInfo *rsi) {
FILE *fp;
rio rdb;
int retval;
if ((fp = fopen(filename,"r")) == NULL) return C_ERR;
startLoading(fp);
rioInitWithFile(&rdb,fp);
retval = rdbLoadRio(&rdb,rsi);
fclose(fp);
stopLoading();
return retval;
}
/* A background saving child (BGSAVE) terminated its work. Handle this.
* This function covers the case of actual BGSAVEs. */
void backgroundSaveDoneHandlerDisk(int exitcode, int bysignal) {
if (!bysignal && exitcode == 0) {
serverLog(LL_NOTICE,
"Background saving terminated with success");
server.dirty = server.dirty - server.dirty_before_bgsave;
server.lastsave = time(NULL);
server.lastbgsave_status = C_OK;
} else if (!bysignal && exitcode != 0) {
serverLog(LL_WARNING, "Background saving error");
server.lastbgsave_status = C_ERR;
} else {
mstime_t latency;
serverLog(LL_WARNING,
"Background saving terminated by signal %d", bysignal);
latencyStartMonitor(latency);
rdbRemoveTempFile(server.rdb_child_pid);
latencyEndMonitor(latency);
latencyAddSampleIfNeeded("rdb-unlink-temp-file",latency);
/* SIGUSR1 is whitelisted, so we have a way to kill a child without
* tirggering an error conditon. */
if (bysignal != SIGUSR1)
server.lastbgsave_status = C_ERR;
}
server.rdb_child_pid = -1;
server.rdb_child_type = RDB_CHILD_TYPE_NONE;
server.rdb_save_time_last = time(NULL)-server.rdb_save_time_start;
server.rdb_save_time_start = -1;
/* Possibly there are slaves waiting for a BGSAVE in order to be served
* (the first stage of SYNC is a bulk transfer of dump.rdb) */
updateSlavesWaitingBgsave((!bysignal && exitcode == 0) ? C_OK : C_ERR, RDB_CHILD_TYPE_DISK);
}
/* A background saving child (BGSAVE) terminated its work. Handle this.
* This function covers the case of RDB -> Salves socket transfers for
* diskless replication. */
void backgroundSaveDoneHandlerSocket(int exitcode, int bysignal) {
uint64_t *ok_slaves;
if (!bysignal && exitcode == 0) {
serverLog(LL_NOTICE,
"Background RDB transfer terminated with success");
} else if (!bysignal && exitcode != 0) {
serverLog(LL_WARNING, "Background transfer error");
} else {
serverLog(LL_WARNING,
"Background transfer terminated by signal %d", bysignal);
}
server.rdb_child_pid = -1;
server.rdb_child_type = RDB_CHILD_TYPE_NONE;
server.rdb_save_time_start = -1;
/* If the child returns an OK exit code, read the set of slave client
* IDs and the associated status code. We'll terminate all the slaves
* in error state.
*
* If the process returned an error, consider the list of slaves that
* can continue to be emtpy, so that it's just a special case of the
* normal code path. */
ok_slaves = zmalloc(sizeof(uint64_t)); /* Make space for the count. */
ok_slaves[0] = 0;
if (!bysignal && exitcode == 0) {
int readlen = sizeof(uint64_t);
if (read(server.rdb_pipe_read_result_from_child, ok_slaves, readlen) ==
readlen)
{
readlen = ok_slaves[0]*sizeof(uint64_t)*2;
/* Make space for enough elements as specified by the first
* uint64_t element in the array. */
ok_slaves = zrealloc(ok_slaves,sizeof(uint64_t)+readlen);
if (readlen &&
read(server.rdb_pipe_read_result_from_child, ok_slaves+1,
readlen) != readlen)
{
ok_slaves[0] = 0;
}
}
}
close(server.rdb_pipe_read_result_from_child);
close(server.rdb_pipe_write_result_to_parent);
/* We can continue the replication process with all the slaves that
* correctly received the full payload. Others are terminated. */
listNode *ln;
listIter li;
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {
client *slave = ln->value;
if (slave->replstate == SLAVE_STATE_WAIT_BGSAVE_END) {
uint64_t j;
int errorcode = 0;
/* Search for the slave ID in the reply. In order for a slave to
* continue the replication process, we need to find it in the list,
* and it must have an error code set to 0 (which means success). */
for (j = 0; j < ok_slaves[0]; j++) {
if (slave->id == ok_slaves[2*j+1]) {
errorcode = ok_slaves[2*j+2];
break; /* Found in slaves list. */
}
}
if (j == ok_slaves[0] || errorcode != 0) {
serverLog(LL_WARNING,
"Closing slave %s: child->slave RDB transfer failed: %s",
replicationGetSlaveName(slave),
(errorcode == 0) ? "RDB transfer child aborted"
: strerror(errorcode));
freeClient(slave);
} else {
serverLog(LL_WARNING,
"Slave %s correctly received the streamed RDB file.",
replicationGetSlaveName(slave));
/* Restore the socket as non-blocking. */
anetNonBlock(NULL,slave->fd);
anetSendTimeout(NULL,slave->fd,0);
}
}
}
zfree(ok_slaves);
updateSlavesWaitingBgsave((!bysignal && exitcode == 0) ? C_OK : C_ERR, RDB_CHILD_TYPE_SOCKET);
}
/* When a background RDB saving/transfer terminates, call the right handler. */
void backgroundSaveDoneHandler(int exitcode, int bysignal) {
switch(server.rdb_child_type) {
case RDB_CHILD_TYPE_DISK:
backgroundSaveDoneHandlerDisk(exitcode,bysignal);
break;
case RDB_CHILD_TYPE_SOCKET:
backgroundSaveDoneHandlerSocket(exitcode,bysignal);
break;
default:
serverPanic("Unknown RDB child type.");
break;
}
}
/* Spawn an RDB child that writes the RDB to the sockets of the slaves
* that are currently in SLAVE_STATE_WAIT_BGSAVE_START state. */
int rdbSaveToSlavesSockets(rdbSaveInfo *rsi) {
int *fds;
uint64_t *clientids;
int numfds;
listNode *ln;
listIter li;
pid_t childpid;
long long start;
int pipefds[2];
if (server.aof_child_pid != -1 || server.rdb_child_pid != -1) return C_ERR;
/* Before to fork, create a pipe that will be used in order to
* send back to the parent the IDs of the slaves that successfully
* received all the writes. */
if (pipe(pipefds) == -1) return C_ERR;
server.rdb_pipe_read_result_from_child = pipefds[0];
server.rdb_pipe_write_result_to_parent = pipefds[1];
/* Collect the file descriptors of the slaves we want to transfer
* the RDB to, which are i WAIT_BGSAVE_START state. */
fds = zmalloc(sizeof(int)*listLength(server.slaves));
/* We also allocate an array of corresponding client IDs. This will
* be useful for the child process in order to build the report
* (sent via unix pipe) that will be sent to the parent. */
clientids = zmalloc(sizeof(uint64_t)*listLength(server.slaves));
numfds = 0;
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {
client *slave = ln->value;
if (slave->replstate == SLAVE_STATE_WAIT_BGSAVE_START) {
clientids[numfds] = slave->id;
fds[numfds++] = slave->fd;
replicationSetupSlaveForFullResync(slave,getPsyncInitialOffset());
/* Put the socket in blocking mode to simplify RDB transfer.
* We'll restore it when the children returns (since duped socket
* will share the O_NONBLOCK attribute with the parent). */
anetBlock(NULL,slave->fd);
anetSendTimeout(NULL,slave->fd,server.repl_timeout*1000);
}
}
/* Create the child process. */
openChildInfoPipe();
start = ustime();
if ((childpid = fork()) == 0) {
/* Child */
int retval;
rio slave_sockets;
rioInitWithFdset(&slave_sockets,fds,numfds);
zfree(fds);
closeListeningSockets(0);
redisSetProcTitle("redis-rdb-to-slaves");
retval = rdbSaveRioWithEOFMark(&slave_sockets,NULL,rsi);
if (retval == C_OK && rioFlush(&slave_sockets) == 0)
retval = C_ERR;
if (retval == C_OK) {
size_t private_dirty = zmalloc_get_private_dirty(-1);
if (private_dirty) {
serverLog(LL_NOTICE,
"RDB: %zu MB of memory used by copy-on-write",
private_dirty/(1024*1024));
}
server.child_info_data.cow_size = private_dirty;
sendChildInfo(CHILD_INFO_TYPE_RDB);
/* If we are returning OK, at least one slave was served
* with the RDB file as expected, so we need to send a report
* to the parent via the pipe. The format of the message is:
*
* <len> <slave[0].id> <slave[0].error> ...
*
* len, slave IDs, and slave errors, are all uint64_t integers,
* so basically the reply is composed of 64 bits for the len field
* plus 2 additional 64 bit integers for each entry, for a total
* of 'len' entries.
*
* The 'id' represents the slave's client ID, so that the master
* can match the report with a specific slave, and 'error' is
* set to 0 if the replication process terminated with a success
* or the error code if an error occurred. */
void *msg = zmalloc(sizeof(uint64_t)*(1+2*numfds));
uint64_t *len = msg;
uint64_t *ids = len+1;
int j, msglen;
*len = numfds;
for (j = 0; j < numfds; j++) {
*ids++ = clientids[j];
*ids++ = slave_sockets.io.fdset.state[j];
}
/* Write the message to the parent. If we have no good slaves or
* we are unable to transfer the message to the parent, we exit
* with an error so that the parent will abort the replication
* process with all the childre that were waiting. */
msglen = sizeof(uint64_t)*(1+2*numfds);
if (*len == 0 ||
write(server.rdb_pipe_write_result_to_parent,msg,msglen)
!= msglen)
{
retval = C_ERR;
}
zfree(msg);
}
zfree(clientids);
rioFreeFdset(&slave_sockets);
exitFromChild((retval == C_OK) ? 0 : 1);
} else {
/* Parent */
if (childpid == -1) {
serverLog(LL_WARNING,"Can't save in background: fork: %s",
strerror(errno));
/* Undo the state change. The caller will perform cleanup on
* all the slaves in BGSAVE_START state, but an early call to
* replicationSetupSlaveForFullResync() turned it into BGSAVE_END */
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {
client *slave = ln->value;
int j;
for (j = 0; j < numfds; j++) {
if (slave->id == clientids[j]) {
slave->replstate = SLAVE_STATE_WAIT_BGSAVE_START;
break;
}
}
}
close(pipefds[0]);
close(pipefds[1]);
closeChildInfoPipe();
} else {
server.stat_fork_time = ustime()-start;
server.stat_fork_rate = (double) zmalloc_used_memory() * 1000000 / server.stat_fork_time / (1024*1024*1024); /* GB per second. */
latencyAddSampleIfNeeded("fork",server.stat_fork_time/1000);
serverLog(LL_NOTICE,"Background RDB transfer started by pid %d",
childpid);
server.rdb_save_time_start = time(NULL);
server.rdb_child_pid = childpid;
server.rdb_child_type = RDB_CHILD_TYPE_SOCKET;
updateDictResizePolicy();
}
zfree(clientids);
zfree(fds);
return (childpid == -1) ? C_ERR : C_OK;
}
return C_OK; /* Unreached. */
}
void saveCommand(client *c) {
if (server.rdb_child_pid != -1) {
addReplyError(c,"Background save already in progress");
return;
}
rdbSaveInfo rsi, *rsiptr;
rsiptr = rdbPopulateSaveInfo(&rsi);
if (rdbSave(server.rdb_filename,rsiptr) == C_OK) {
addReply(c,shared.ok);
} else {
addReply(c,shared.err);
}
}
/* BGSAVE [SCHEDULE] */
void bgsaveCommand(client *c) {
int schedule = 0;
/* The SCHEDULE option changes the behavior of BGSAVE when an AOF rewrite
* is in progress. Instead of returning an error a BGSAVE gets scheduled. */
if (c->argc > 1) {
if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"schedule")) {
schedule = 1;
} else {
addReply(c,shared.syntaxerr);
return;
}
}
rdbSaveInfo rsi, *rsiptr;
rsiptr = rdbPopulateSaveInfo(&rsi);
if (server.rdb_child_pid != -1) {
addReplyError(c,"Background save already in progress");
} else if (server.aof_child_pid != -1) {
if (schedule) {
server.rdb_bgsave_scheduled = 1;
addReplyStatus(c,"Background saving scheduled");
} else {
addReplyError(c,
"An AOF log rewriting in progress: can't BGSAVE right now. "
"Use BGSAVE SCHEDULE in order to schedule a BGSAVE whenever "
"possible.");
}
} else if (rdbSaveBackground(server.rdb_filename,rsiptr) == C_OK) {
addReplyStatus(c,"Background saving started");
} else {
addReply(c,shared.err);
}
}
/* Populate the rdbSaveInfo structure used to persist the replication
* information inside the RDB file. Currently the structure explicitly
* contains just the currently selected DB from the master stream, however
* if the rdbSave*() family functions receive a NULL rsi structure also
* the Replication ID/offset is not saved. The function popultes 'rsi'
* that is normally stack-allocated in the caller, returns the populated
* pointer if the instance has a valid master client, otherwise NULL
* is returned, and the RDB saving will not persist any replication related
* information. */
rdbSaveInfo *rdbPopulateSaveInfo(rdbSaveInfo *rsi) {
rdbSaveInfo rsi_init = RDB_SAVE_INFO_INIT;
*rsi = rsi_init;
/* If the instance is a master, we can populate the replication info
* only when repl_backlog is not NULL. If the repl_backlog is NULL,
* it means that the instance isn't in any replication chains. In this
* scenario the replication info is useless, because when a slave
* connects to us, the NULL repl_backlog will trigger a full
* synchronization, at the same time we will use a new replid and clear
* replid2. */
if (!server.masterhost && server.repl_backlog) {
/* Note that when server.slaveseldb is -1, it means that this master
* didn't apply any write commands after a full synchronization.
* So we can let repl_stream_db be 0, this allows a restarted slave
* to reload replication ID/offset, it's safe because the next write
* command must generate a SELECT statement. */
rsi->repl_stream_db = server.slaveseldb == -1 ? 0 : server.slaveseldb;
return rsi;
}
/* If the instance is a slave we need a connected master
* in order to fetch the currently selected DB. */
if (server.master) {
rsi->repl_stream_db = server.master->db->id;
return rsi;
}
/* If we have a cached master we can use it in order to populate the
* replication selected DB info inside the RDB file: the slave can
* increment the master_repl_offset only from data arriving from the
* master, so if we are disconnected the offset in the cached master
* is valid. */
if (server.cached_master) {
rsi->repl_stream_db = server.cached_master->db->id;
return rsi;
}
return NULL;
}