return 0;
}
+/* check rdbLoadLen() comments for more info */
static int rdbSaveLen(FILE *fp, uint32_t len) {
unsigned char buf[2];
return 0;
}
+/* 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(sds s, 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;
+ snprintf(buf,32,"%lld",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) != sdslen(s) || memcmp(buf,s,sdslen(s))) return 0;
+
+ /* Finally check if it fits in our ranges */
+ 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;
+ }
+}
+
+/* Save a string objet as [len][data] on disk. If the object is a string
+ * representation of an integer value we try to safe it in a special form */
static int rdbSaveStringObject(FILE *fp, robj *obj) {
size_t len = sdslen(obj->ptr);
+ int enclen;
+ if (len <= 11) {
+ unsigned char buf[5];
+ if ((enclen = rdbTryIntegerEncoding(obj->ptr,buf)) > 0) {
+ if (fwrite(buf,enclen,1,fp) == 0) return -1;
+ return 0;
+ }
+ }
if (rdbSaveLen(fp,len) == -1) return -1;
if (len && fwrite(obj->ptr,len,1,fp) == 0) return -1;
return 0;
return type;
}
-static uint32_t rdbLoadLen(FILE *fp, int rdbver) {
+/* Load an encoded length from the DB, see the REDIS_RDB_* defines on the top
+ * of this file for a description of how this are stored on disk.
+ *
+ * isencoded is set to 1 if the readed length is not actually a length but
+ * an "encoding type", check the above comments for more info */
+static uint32_t rdbLoadLen(FILE *fp, int rdbver, int *isencoded) {
unsigned char buf[2];
uint32_t len;
+ if (isencoded) *isencoded = 0;
if (rdbver == 0) {
if (fread(&len,4,1,fp) == 0) return REDIS_RDB_LENERR;
return ntohl(len);
type = (buf[0]&0xC0)>>6;
if (type == REDIS_RDB_6BITLEN) {
/* Read a 6 bit len */
- return buf[0];
+ return buf[0]&0x3F;
+ } else if (type == REDIS_RDB_ENCVAL) {
+ /* Read a 6 bit len encoding type */
+ if (isencoded) *isencoded = 1;
+ return buf[0]&0x3F;
} else if (type == REDIS_RDB_14BITLEN) {
/* Read a 14 bit len */
if (fread(buf+1,1,1,fp) == 0) return REDIS_RDB_LENERR;
}
}
-static robj *rdbLoadStringObject(FILE*fp,int rdbver) {
- uint32_t len = rdbLoadLen(fp,rdbver);
+static robj *rdbLoadIntegerObject(FILE *fp, int enctype) {
+ unsigned char enc[4];
+ long long val;
+
+ if (enctype == REDIS_RDB_ENC_INT8) {
+ if (fread(enc,1,1,fp) == 0) return NULL;
+ val = (signed char)enc[0];
+ } else if (enctype == REDIS_RDB_ENC_INT16) {
+ uint16_t v;
+ if (fread(enc,2,1,fp) == 0) return NULL;
+ v = enc[0]|(enc[1]<<8);
+ val = (int16_t)v;
+ } else if (enctype == REDIS_RDB_ENC_INT32) {
+ uint32_t v;
+ if (fread(enc,4,1,fp) == 0) return NULL;
+ v = enc[0]|(enc[1]<<8)|(enc[2]<<16)|(enc[3]<<24);
+ val = (int32_t)v;
+ } else {
+ val = 0; /* anti-warning */
+ assert(0!=0);
+ }
+ return createObject(REDIS_STRING,sdscatprintf(sdsempty(),"%lld",val));
+}
+
+static robj *rdbLoadStringObject(FILE*fp, int rdbver) {
+ int isencoded;
+ uint32_t len;
sds val;
+ len = rdbLoadLen(fp,rdbver,&isencoded);
+ if (isencoded) {
+ switch(len) {
+ case REDIS_RDB_ENC_INT8:
+ case REDIS_RDB_ENC_INT16:
+ case REDIS_RDB_ENC_INT32:
+ return rdbLoadIntegerObject(fp,len);
+ default:
+ assert(0!=0);
+ }
+ }
+
if (len == REDIS_RDB_LENERR) return NULL;
val = sdsnewlen(NULL,len);
if (len && fread(val,len,1,fp) == 0) {
if (type == REDIS_EOF) break;
/* Handle SELECT DB opcode as a special case */
if (type == REDIS_SELECTDB) {
- if ((dbid = rdbLoadLen(fp,rdbver)) == REDIS_RDB_LENERR) goto eoferr;
+ if ((dbid = rdbLoadLen(fp,rdbver,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);
/* Read list/set value */
uint32_t listlen;
- if ((listlen = rdbLoadLen(fp,rdbver)) == REDIS_RDB_LENERR)
+ if ((listlen = rdbLoadLen(fp,rdbver,NULL)) == REDIS_RDB_LENERR)
goto eoferr;
o = (type == REDIS_LIST) ? createListObject() : createSetObject();
/* Load every single element of the list/set */
return REDIS_OK;
eoferr: /* unexpected end of file is handled here with a fatal exit */
- decrRefCount(keyobj);
- redisLog(REDIS_WARNING,"Short read loading DB. Unrecoverable error, exiting now.");
+ if (keyobj) decrRefCount(keyobj);
+ redisLog(REDIS_WARNING,"Short read or OOM loading DB. Unrecoverable error, exiting now.");
exit(1);
return REDIS_ERR; /* Just to avoid warning */
}
projects / redis.git / commitdiff
