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#include "redis.h"
#include "lzf.h" /* LZF compression library */
#include "zipmap.h"
#include "endianconv.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>
static int rdbWriteRaw(rio *rdb, void *p, size_t len) {
if (rdb && rioWrite(rdb,p,len) == 0)
return -1;
return len;
}
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;
if (rioRead(rdb,&t32,4) == 0) return -1;
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;
if (rioRead(rdb,&t64,8) == 0) return -1;
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 REDIS_RDB_* definitions for more information
* on the types of encoding. */
int rdbSaveLen(rio *rdb, uint32_t len) {
unsigned char buf[2];
size_t nwritten;
if (len < (1<<6)) {
/* Save a 6 bit len */
buf[0] = (len&0xFF)|(REDIS_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)|(REDIS_RDB_14BITLEN<<6);
buf[1] = len&0xFF;
if (rdbWriteRaw(rdb,buf,2) == -1) return -1;
nwritten = 2;
} else {
/* Save a 32 bit len */
buf[0] = (REDIS_RDB_32BITLEN<<6);
if (rdbWriteRaw(rdb,buf,1) == -1) return -1;
len = htonl(len);
if (rdbWriteRaw(rdb,&len,4) == -4) return -1;
nwritten = 1+4;
}
return nwritten;
}
/* Load an encoded length. The "isencoded" argument is set to 1 if the length
* is not actually a length but an "encoding type". See the REDIS_RDB_ENC_*
* definitions in rdb.h for more information. */
uint32_t rdbLoadLen(rio *rdb, int *isencoded) {
unsigned char buf[2];
uint32_t len;
int type;
if (isencoded) *isencoded = 0;
if (rioRead(rdb,buf,1) == 0) return REDIS_RDB_LENERR;
type = (buf[0]&0xC0)>>6;
if (type == REDIS_RDB_ENCVAL) {
/* Read a 6 bit encoding type. */
if (isencoded) *isencoded = 1;
return buf[0]&0x3F;
} else if (type == REDIS_RDB_6BITLEN) {
/* Read a 6 bit len. */
return buf[0]&0x3F;
} else if (type == REDIS_RDB_14BITLEN) {
/* Read a 14 bit len. */
if (rioRead(rdb,buf+1,1) == 0) return REDIS_RDB_LENERR;
return ((buf[0]&0x3F)<<8)|buf[1];
} else {
/* Read a 32 bit len. */
if (rioRead(rdb,&len,4) == 0) return REDIS_RDB_LENERR;
return ntohl(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] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT8;
enc[1] = value&0xFF;
return 2;
} else if (value >= -(1<<15) && value <= (1<<15)-1) {
enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_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] = (REDIS_RDB_ENCVAL<<6)|REDIS_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".
* If the "encode" argument is set the function may return an integer-encoded
* string object, otherwise it always returns a raw string object. */
robj *rdbLoadIntegerObject(rio *rdb, int enctype, int encode) {
unsigned char enc[4];
long long val;
if (enctype == REDIS_RDB_ENC_INT8) {
if (rioRead(rdb,enc,1) == 0) return NULL;
val = (signed char)enc[0];
} else if (enctype == REDIS_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 == REDIS_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 */
redisPanic("Unknown RDB integer encoding type");
}
if (encode)
return createStringObjectFromLongLong(val);
else
return createObject(REDIS_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);
}
int rdbSaveLzfStringObject(rio *rdb, unsigned char *s, size_t len) {
size_t comprlen, outlen;
unsigned char byte;
int n, nwritten = 0;
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;
}
/* Data compressed! Let's save it on disk */
byte = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_LZF;
if ((n = rdbWriteRaw(rdb,&byte,1)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbSaveLen(rdb,comprlen)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbSaveLen(rdb,len)) == -1) goto writeerr;
nwritten += n;
if ((n = rdbWriteRaw(rdb,out,comprlen)) == -1) goto writeerr;
nwritten += n;
zfree(out);
return nwritten;
writeerr:
zfree(out);
return -1;
}
robj *rdbLoadLzfStringObject(rio *rdb) {
unsigned int len, clen;
unsigned char *c = NULL;
sds val = NULL;
if ((clen = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL;
if ((len = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL;
if ((c = zmalloc(clen)) == NULL) goto err;
if ((val = sdsnewlen(NULL,len)) == NULL) goto err;
if (rioRead(rdb,c,clen) == 0) goto err;
if (lzf_decompress(c,clen,val,len) == 0) goto err;
zfree(c);
return createObject(REDIS_STRING,val);
err:
zfree(c);
sdsfree(val);
return NULL;
}
/* Save a string objet 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 */
int rdbSaveRawString(rio *rdb, unsigned char *s, size_t len) {
int enclen;
int 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. */
int rdbSaveLongLongAsStringObject(rio *rdb, long long value) {
unsigned char buf[32];
int 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);
redisAssert(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 rdbSaveStringObjectRaw() but handle encoded objects */
int rdbSaveStringObject(rio *rdb, robj *obj) {
/* Avoid to decode the object, then encode it again, if the
* object is alrady integer encoded. */
if (obj->encoding == REDIS_ENCODING_INT) {
return rdbSaveLongLongAsStringObject(rdb,(long)obj->ptr);
} else {
redisAssertWithInfo(NULL,obj,obj->encoding == REDIS_ENCODING_RAW);
return rdbSaveRawString(rdb,obj->ptr,sdslen(obj->ptr));
}
}
robj *rdbGenericLoadStringObject(rio *rdb, int encode) {
int isencoded;
uint32_t len;
sds val;
len = rdbLoadLen(rdb,&isencoded);
if (isencoded) {
switch(len) {
case REDIS_RDB_ENC_INT8:
case REDIS_RDB_ENC_INT16:
case REDIS_RDB_ENC_INT32:
return rdbLoadIntegerObject(rdb,len,encode);
case REDIS_RDB_ENC_LZF:
return rdbLoadLzfStringObject(rdb);
default:
redisPanic("Unknown RDB encoding type");
}
}
if (len == REDIS_RDB_LENERR) return NULL;
val = sdsnewlen(NULL,len);
if (len && rioRead(rdb,val,len) == 0) {
sdsfree(val);
return NULL;
}
return createObject(REDIS_STRING,val);
}
robj *rdbLoadStringObject(rio *rdb) {
return rdbGenericLoadStringObject(rdb,0);
}
robj *rdbLoadEncodedStringObject(rio *rdb) {
return rdbGenericLoadStringObject(rdb,1);
}
/* Save a double value. Doubles are saved as strings prefixed by an unsigned
* 8 bit integer specifing 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),(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[128];
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;
}
}
/* Save the object type of object "o". */
int rdbSaveObjectType(rio *rdb, robj *o) {
switch (o->type) {
case REDIS_STRING:
return rdbSaveType(rdb,REDIS_RDB_TYPE_STRING);
case REDIS_LIST:
if (o->encoding == REDIS_ENCODING_ZIPLIST)
return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST_ZIPLIST);
else if (o->encoding == REDIS_ENCODING_LINKEDLIST)
return rdbSaveType(rdb,REDIS_RDB_TYPE_LIST);
else
redisPanic("Unknown list encoding");
case REDIS_SET:
if (o->encoding == REDIS_ENCODING_INTSET)
return rdbSaveType(rdb,REDIS_RDB_TYPE_SET_INTSET);
else if (o->encoding == REDIS_ENCODING_HT)
return rdbSaveType(rdb,REDIS_RDB_TYPE_SET);
else
redisPanic("Unknown set encoding");
case REDIS_ZSET:
if (o->encoding == REDIS_ENCODING_ZIPLIST)
return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET_ZIPLIST);
else if (o->encoding == REDIS_ENCODING_SKIPLIST)
return rdbSaveType(rdb,REDIS_RDB_TYPE_ZSET);
else
redisPanic("Unknown sorted set encoding");
case REDIS_HASH:
if (o->encoding == REDIS_ENCODING_ZIPLIST)
return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH_ZIPLIST);
else if (o->encoding == REDIS_ENCODING_HT)
return rdbSaveType(rdb,REDIS_RDB_TYPE_HASH);
else
redisPanic("Unknown hash encoding");
default:
redisPanic("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;
}
/* Save a Redis object. Returns -1 on error, 0 on success. */
int rdbSaveObject(rio *rdb, robj *o) {
int n, nwritten = 0;
if (o->type == REDIS_STRING) {
/* Save a string value */
if ((n = rdbSaveStringObject(rdb,o)) == -1) return -1;
nwritten += n;
} else if (o->type == REDIS_LIST) {
/* Save a list value */
if (o->encoding == REDIS_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 == REDIS_ENCODING_LINKEDLIST) {
list *list = o->ptr;
listIter li;
listNode *ln;
if ((n = rdbSaveLen(rdb,listLength(list))) == -1) return -1;
nwritten += n;
listRewind(list,&li);
while((ln = listNext(&li))) {
robj *eleobj = listNodeValue(ln);
if ((n = rdbSaveStringObject(rdb,eleobj)) == -1) return -1;
nwritten += n;
}
} else {
redisPanic("Unknown list encoding");
}
} else if (o->type == REDIS_SET) {
/* Save a set value */
if (o->encoding == REDIS_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) {
robj *eleobj = dictGetKey(de);
if ((n = rdbSaveStringObject(rdb,eleobj)) == -1) return -1;
nwritten += n;
}
dictReleaseIterator(di);
} else if (o->encoding == REDIS_ENCODING_INTSET) {
size_t l = intsetBlobLen((intset*)o->ptr);
if ((n = rdbSaveRawString(rdb,o->ptr,l)) == -1) return -1;
nwritten += n;
} else {
redisPanic("Unknown set encoding");
}
} else if (o->type == REDIS_ZSET) {
/* Save a sorted set value */
if (o->encoding == REDIS_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 == REDIS_ENCODING_SKIPLIST) {
zset *zs = o->ptr;
dictIterator *di = dictGetIterator(zs->dict);
dictEntry *de;
if ((n = rdbSaveLen(rdb,dictSize(zs->dict))) == -1) return -1;
nwritten += n;
while((de = dictNext(di)) != NULL) {
robj *eleobj = dictGetKey(de);
double *score = dictGetVal(de);
if ((n = rdbSaveStringObject(rdb,eleobj)) == -1) return -1;
nwritten += n;
if ((n = rdbSaveDoubleValue(rdb,*score)) == -1) return -1;
nwritten += n;
}
dictReleaseIterator(di);
} else {
redisPanic("Unknown sorted set encoding");
}
} else if (o->type == REDIS_HASH) {
/* Save a hash value */
if (o->encoding == REDIS_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 == REDIS_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) {
robj *key = dictGetKey(de);
robj *val = dictGetVal(de);
if ((n = rdbSaveStringObject(rdb,key)) == -1) return -1;
nwritten += n;
if ((n = rdbSaveStringObject(rdb,val)) == -1) return -1;
nwritten += n;
}
dictReleaseIterator(di);
} else {
redisPanic("Unknown hash encoding");
}
} else {
redisPanic("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. */
off_t rdbSavedObjectLen(robj *o) {
int len = rdbSaveObject(NULL,o);
redisAssertWithInfo(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 actaully 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)
{
/* Save the expire time */
if (expiretime != -1) {
/* If this key is already expired skip it */
if (expiretime < now) return 0;
if (rdbSaveType(rdb,REDIS_RDB_OPCODE_EXPIRETIME_MS) == -1) return -1;
if (rdbSaveMillisecondTime(rdb,expiretime) == -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 the DB on disk. Return REDIS_ERR on error, REDIS_OK on success */
int rdbSave(char *filename) {
dictIterator *di = NULL;
dictEntry *de;
char tmpfile[256];
char magic[10];
int j;
long long now = mstime();
FILE *fp;
rio rdb;
uint64_t cksum;
snprintf(tmpfile,256,"temp-%d.rdb", (int) getpid());
fp = fopen(tmpfile,"w");
if (!fp) {
redisLog(REDIS_WARNING, "Failed opening .rdb for saving: %s",
strerror(errno));
return REDIS_ERR;
}
rioInitWithFile(&rdb,fp);
if (server.rdb_checksum)
rdb.update_cksum = rioGenericUpdateChecksum;
snprintf(magic,sizeof(magic),"REDIS%04d",REDIS_RDB_VERSION);
if (rdbWriteRaw(&rdb,magic,9) == -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) {
fclose(fp);
return REDIS_ERR;
}
/* Write the SELECT DB opcode */
if (rdbSaveType(&rdb,REDIS_RDB_OPCODE_SELECTDB) == -1) goto werr;
if (rdbSaveLen(&rdb,j) == -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;
}
dictReleaseIterator(di);
}
di = NULL; /* So that we don't release it again on error. */
/* EOF opcode */
if (rdbSaveType(&rdb,REDIS_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);
rioWrite(&rdb,&cksum,8);
/* Make sure data will not remain on the OS's output buffers */
fflush(fp);
fsync(fileno(fp));
fclose(fp);
/* Use RENAME to make sure the DB file is changed atomically only
* if the generate DB file is ok. */
if (rename(tmpfile,filename) == -1) {
redisLog(REDIS_WARNING,"Error moving temp DB file on the final destination: %s", strerror(errno));
unlink(tmpfile);
return REDIS_ERR;
}
redisLog(REDIS_NOTICE,"DB saved on disk");
server.dirty = 0;
server.lastsave = time(NULL);
server.lastbgsave_status = REDIS_OK;
return REDIS_OK;
werr:
fclose(fp);
unlink(tmpfile);
redisLog(REDIS_WARNING,"Write error saving DB on disk: %s", strerror(errno));
if (di) dictReleaseIterator(di);
return REDIS_ERR;
}
int rdbSaveBackground(char *filename) {
pid_t childpid;
long long start;
if (server.rdb_child_pid != -1) return REDIS_ERR;
server.dirty_before_bgsave = server.dirty;
start = ustime();
if ((childpid = fork()) == 0) {
int retval;
/* Child */
if (server.ipfd > 0) close(server.ipfd);
if (server.sofd > 0) close(server.sofd);
retval = rdbSave(filename);
exitFromChild((retval == REDIS_OK) ? 0 : 1);
} else {
/* Parent */
server.stat_fork_time = ustime()-start;
if (childpid == -1) {
redisLog(REDIS_WARNING,"Can't save in background: fork: %s",
strerror(errno));
return REDIS_ERR;
}
redisLog(REDIS_NOTICE,"Background saving started by pid %d",childpid);
server.rdb_save_time_start = time(NULL);
server.rdb_child_pid = childpid;
updateDictResizePolicy();
return REDIS_OK;
}
return REDIS_OK; /* unreached */
}
void rdbRemoveTempFile(pid_t childpid) {
char tmpfile[256];
snprintf(tmpfile,256,"temp-%d.rdb", (int) childpid);
unlink(tmpfile);
}
/* 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, *ele, *dec;
size_t len;
unsigned int i;
redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",rdbtype,rioTell(rdb));
if (rdbtype == REDIS_RDB_TYPE_STRING) {
/* Read string value */
if ((o = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
o = tryObjectEncoding(o);
} else if (rdbtype == REDIS_RDB_TYPE_LIST) {
/* Read list value */
if ((len = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL;
/* Use a real list when there are too many entries */
if (len > server.list_max_ziplist_entries) {
o = createListObject();
} else {
o = createZiplistObject();
}
/* Load every single element of the list */
while(len--) {
if ((ele = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
/* If we are using a ziplist and the value is too big, convert
* the object to a real list. */
if (o->encoding == REDIS_ENCODING_ZIPLIST &&
ele->encoding == REDIS_ENCODING_RAW &&
sdslen(ele->ptr) > server.list_max_ziplist_value)
listTypeConvert(o,REDIS_ENCODING_LINKEDLIST);
if (o->encoding == REDIS_ENCODING_ZIPLIST) {
dec = getDecodedObject(ele);
o->ptr = ziplistPush(o->ptr,dec->ptr,sdslen(dec->ptr),REDIS_TAIL);
decrRefCount(dec);
decrRefCount(ele);
} else {
ele = tryObjectEncoding(ele);
listAddNodeTail(o->ptr,ele);
}
}
} else if (rdbtype == REDIS_RDB_TYPE_SET) {
/* Read list/set value */
if ((len = rdbLoadLen(rdb,NULL)) == REDIS_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 list/set */
for (i = 0; i < len; i++) {
long long llval;
if ((ele = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
ele = tryObjectEncoding(ele);
if (o->encoding == REDIS_ENCODING_INTSET) {
/* Fetch integer value from element */
if (isObjectRepresentableAsLongLong(ele,&llval) == REDIS_OK) {
o->ptr = intsetAdd(o->ptr,llval,NULL);
} else {
setTypeConvert(o,REDIS_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 == REDIS_ENCODING_HT) {
dictAdd((dict*)o->ptr,ele,NULL);
} else {
decrRefCount(ele);
}
}
} else if (rdbtype == REDIS_RDB_TYPE_ZSET) {
/* Read list/set value */
size_t zsetlen;
size_t maxelelen = 0;
zset *zs;
if ((zsetlen = rdbLoadLen(rdb,NULL)) == REDIS_RDB_LENERR) return NULL;
o = createZsetObject();
zs = o->ptr;
/* Load every single element of the list/set */
while(zsetlen--) {
robj *ele;
double score;
zskiplistNode *znode;
if ((ele = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
ele = tryObjectEncoding(ele);
if (rdbLoadDoubleValue(rdb,&score) == -1) return NULL;
/* Don't care about integer-encoded strings. */
if (ele->encoding == REDIS_ENCODING_RAW &&
sdslen(ele->ptr) > maxelelen)
maxelelen = sdslen(ele->ptr);
znode = zslInsert(zs->zsl,score,ele);
dictAdd(zs->dict,ele,&znode->score);
incrRefCount(ele); /* added to skiplist */
}
/* 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,REDIS_ENCODING_ZIPLIST);
} else if (rdbtype == REDIS_RDB_TYPE_HASH) {
size_t len;
int ret;
len = rdbLoadLen(rdb, NULL);
if (len == REDIS_RDB_LENERR) return NULL;
o = createHashObject();
/* Too many entries? Use an hash table. */
if (len > server.hash_max_ziplist_entries)
hashTypeConvert(o, REDIS_ENCODING_HT);
/* Load every field and value into the ziplist */
while (o->encoding == REDIS_ENCODING_ZIPLIST && len > 0) {
robj *field, *value;
len--;
/* Load raw strings */
field = rdbLoadStringObject(rdb);
if (field == NULL) return NULL;
redisAssert(field->encoding == REDIS_ENCODING_RAW);
value = rdbLoadStringObject(rdb);
if (value == NULL) return NULL;
redisAssert(field->encoding == REDIS_ENCODING_RAW);
/* Add pair to ziplist */
o->ptr = ziplistPush(o->ptr, field->ptr, sdslen(field->ptr), ZIPLIST_TAIL);
o->ptr = ziplistPush(o->ptr, value->ptr, sdslen(value->ptr), ZIPLIST_TAIL);
/* Convert to hash table if size threshold is exceeded */
if (sdslen(field->ptr) > server.hash_max_ziplist_value ||
sdslen(value->ptr) > server.hash_max_ziplist_value)
{
decrRefCount(field);
decrRefCount(value);
hashTypeConvert(o, REDIS_ENCODING_HT);
break;
}
decrRefCount(field);
decrRefCount(value);
}
/* Load remaining fields and values into the hash table */
while (o->encoding == REDIS_ENCODING_HT && len > 0) {
robj *field, *value;
len--;
/* Load encoded strings */
field = rdbLoadEncodedStringObject(rdb);
if (field == NULL) return NULL;
value = rdbLoadEncodedStringObject(rdb);
if (value == NULL) return NULL;
field = tryObjectEncoding(field);
value = tryObjectEncoding(value);
/* Add pair to hash table */
ret = dictAdd((dict*)o->ptr, field, value);
redisAssert(ret == REDIS_OK);
}
/* All pairs should be read by now */
redisAssert(len == 0);
} else if (rdbtype == REDIS_RDB_TYPE_HASH_ZIPMAP ||
rdbtype == REDIS_RDB_TYPE_LIST_ZIPLIST ||
rdbtype == REDIS_RDB_TYPE_SET_INTSET ||
rdbtype == REDIS_RDB_TYPE_ZSET_ZIPLIST ||
rdbtype == REDIS_RDB_TYPE_HASH_ZIPLIST)
{
robj *aux = rdbLoadStringObject(rdb);
if (aux == NULL) return NULL;
o = createObject(REDIS_STRING,NULL); /* string is just placeholder */
o->ptr = zmalloc(sdslen(aux->ptr));
memcpy(o->ptr,aux->ptr,sdslen(aux->ptr));
decrRefCount(aux);
/* 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 REDIS_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 = REDIS_HASH;
o->encoding = REDIS_ENCODING_ZIPLIST;
if (hashTypeLength(o) > server.hash_max_ziplist_entries ||
maxlen > server.hash_max_ziplist_value)
{
hashTypeConvert(o, REDIS_ENCODING_HT);
}
}
break;
case REDIS_RDB_TYPE_LIST_ZIPLIST:
o->type = REDIS_LIST;
o->encoding = REDIS_ENCODING_ZIPLIST;
if (ziplistLen(o->ptr) > server.list_max_ziplist_entries)
listTypeConvert(o,REDIS_ENCODING_LINKEDLIST);
break;
case REDIS_RDB_TYPE_SET_INTSET:
o->type = REDIS_SET;
o->encoding = REDIS_ENCODING_INTSET;
if (intsetLen(o->ptr) > server.set_max_intset_entries)
setTypeConvert(o,REDIS_ENCODING_HT);
break;
case REDIS_RDB_TYPE_ZSET_ZIPLIST:
o->type = REDIS_ZSET;
o->encoding = REDIS_ENCODING_ZIPLIST;
if (zsetLength(o) > server.zset_max_ziplist_entries)
zsetConvert(o,REDIS_ENCODING_SKIPLIST);
break;
case REDIS_RDB_TYPE_HASH_ZIPLIST:
o->type = REDIS_HASH;
o->encoding = REDIS_ENCODING_ZIPLIST;
if (hashTypeLength(o) > server.hash_max_ziplist_entries)
hashTypeConvert(o, REDIS_ENCODING_HT);
break;
default:
redisPanic("Unknown encoding");
break;
}
} else {
redisPanic("Unknown object type");
}
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);
if (fstat(fileno(fp), &sb) == -1) {
server.loading_total_bytes = 1; /* just to avoid division by zero */
} else {
server.loading_total_bytes = sb.st_size;
}
}
/* Refresh the loading progress info */
void loadingProgress(off_t pos) {
server.loading_loaded_bytes = pos;
}
/* Loading finished */
void stopLoading(void) {
server.loading = 0;
}
int rdbLoad(char *filename) {
uint32_t dbid;
int type, rdbver;
redisDb *db = server.db+0;
char buf[1024];
long long expiretime, now = mstime();
long loops = 0;
FILE *fp;
rio rdb;
fp = fopen(filename,"r");
if (!fp) {
errno = ENOENT;
return REDIS_ERR;
}
rioInitWithFile(&rdb,fp);
if (server.rdb_checksum)
rdb.update_cksum = rioGenericUpdateChecksum;
if (rioRead(&rdb,buf,9) == 0) goto eoferr;
buf[9] = '\0';
if (memcmp(buf,"REDIS",5) != 0) {
fclose(fp);
redisLog(REDIS_WARNING,"Wrong signature trying to load DB from file");
errno = EINVAL;
return REDIS_ERR;
}
rdbver = atoi(buf+5);
if (rdbver < 1 || rdbver > REDIS_RDB_VERSION) {
fclose(fp);
redisLog(REDIS_WARNING,"Can't handle RDB format version %d",rdbver);
errno = EINVAL;
return REDIS_ERR;
}
startLoading(fp);
while(1) {
robj *key, *val;
expiretime = -1;
/* Serve the clients from time to time */
if (!(loops++ % 1000)) {
loadingProgress(rioTell(&rdb));
aeProcessEvents(server.el, AE_FILE_EVENTS|AE_DONT_WAIT);
}
/* Read type. */
if ((type = rdbLoadType(&rdb)) == -1) goto eoferr;
if (type == REDIS_RDB_OPCODE_EXPIRETIME) {
if ((expiretime = rdbLoadTime(&rdb)) == -1) goto eoferr;
/* 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 milliesconds. */
expiretime *= 1000;
} else if (type == REDIS_RDB_OPCODE_EXPIRETIME_MS) {
/* Milliseconds precision expire times introduced with RDB
* version 3. */
if ((expiretime = rdbLoadMillisecondTime(&rdb)) == -1) goto eoferr;
/* We read the time so we need to read the object type again. */
if ((type = rdbLoadType(&rdb)) == -1) goto eoferr;
}
if (type == REDIS_RDB_OPCODE_EOF)
break;
/* Handle SELECT DB opcode as a special case */
if (type == REDIS_RDB_OPCODE_SELECTDB) {
if ((dbid = rdbLoadLen(&rdb,NULL)) == REDIS_RDB_LENERR)
goto eoferr;
if (dbid >= (unsigned)server.dbnum) {
redisLog(REDIS_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 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(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) {
redisLog(REDIS_WARNING,"RDB file was saved with checksum disabled: no check performed.");
} else if (cksum != expected) {
redisLog(REDIS_WARNING,"Wrong RDB checksum. Aborting now.");
exit(1);
}
}
fclose(fp);
stopLoading();
return REDIS_OK;
eoferr: /* unexpected end of file is handled here with a fatal exit */
redisLog(REDIS_WARNING,"Short read or OOM loading DB. Unrecoverable error, aborting now.");
exit(1);
return REDIS_ERR; /* Just to avoid warning */
}
/* A background saving child (BGSAVE) terminated its work. Handle this. */
void backgroundSaveDoneHandler(int exitcode, int bysignal) {
if (!bysignal && exitcode == 0) {
redisLog(REDIS_NOTICE,
"Background saving terminated with success");
server.dirty = server.dirty - server.dirty_before_bgsave;
server.lastsave = time(NULL);
server.lastbgsave_status = REDIS_OK;
} else if (!bysignal && exitcode != 0) {
redisLog(REDIS_WARNING, "Background saving error");
server.lastbgsave_status = REDIS_ERR;
} else {
redisLog(REDIS_WARNING,
"Background saving terminated by signal %d", bysignal);
rdbRemoveTempFile(server.rdb_child_pid);
server.lastbgsave_status = REDIS_ERR;
}
server.rdb_child_pid = -1;
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(exitcode == 0 ? REDIS_OK : REDIS_ERR);
}
void saveCommand(redisClient *c) {
if (server.rdb_child_pid != -1) {
addReplyError(c,"Background save already in progress");
return;
}
if (rdbSave(server.rdb_filename) == REDIS_OK) {
addReply(c,shared.ok);
} else {
addReply(c,shared.err);
}
}
void bgsaveCommand(redisClient *c) {
if (server.rdb_child_pid != -1) {
addReplyError(c,"Background save already in progress");
} else if (server.aof_child_pid != -1) {
addReplyError(c,"Can't BGSAVE while AOF log rewriting is in progress");
} else if (rdbSaveBackground(server.rdb_filename) == REDIS_OK) {
addReplyStatus(c,"Background saving started");
} else {
addReply(c,shared.err);
}
}
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