[redis.git] / src / object.c

#include "redis.h"
#include <math.h>

robj *createObject(int type, void *ptr) {
    robj *o = zmalloc(sizeof(*o));
    o->type = type;
    o->encoding = REDIS_ENCODING_RAW;
    o->ptr = ptr;
    o->refcount = 1;

    /* Set the LRU to the current lruclock (minutes resolution).
     * We do this regardless of the fact VM is active as LRU is also
     * used for the maxmemory directive when Redis is used as cache.
     *
     * Note that this code may run in the context of an I/O thread
     * and accessing server.lruclock in theory is an error
     * (no locks). But in practice this is safe, and even if we read
     * garbage Redis will not fail. */
    o->lru = server.lruclock;
    /* The following is only needed if VM is active, but since the conditional
     * is probably more costly than initializing the field it's better to
     * have every field properly initialized anyway. */
    return o;
}

robj *createStringObject(char *ptr, size_t len) {
    return createObject(REDIS_STRING,sdsnewlen(ptr,len));
}

robj *createStringObjectFromLongLong(long long value) {
    robj *o;
    if (value >= 0 && value < REDIS_SHARED_INTEGERS) {
        incrRefCount(shared.integers[value]);
        o = shared.integers[value];
    } else {
        if (value >= LONG_MIN && value <= LONG_MAX) {
            o = createObject(REDIS_STRING, NULL);
            o->encoding = REDIS_ENCODING_INT;
            o->ptr = (void*)((long)value);
        } else {
            o = createObject(REDIS_STRING,sdsfromlonglong(value));
        }
    }
    return o;
}

robj *dupStringObject(robj *o) {
    redisAssert(o->encoding == REDIS_ENCODING_RAW);
    return createStringObject(o->ptr,sdslen(o->ptr));
}

robj *createListObject(void) {
    list *l = listCreate();
    robj *o = createObject(REDIS_LIST,l);
    listSetFreeMethod(l,decrRefCount);
    o->encoding = REDIS_ENCODING_LINKEDLIST;
    return o;
}

robj *createZiplistObject(void) {
    unsigned char *zl = ziplistNew();
    robj *o = createObject(REDIS_LIST,zl);
    o->encoding = REDIS_ENCODING_ZIPLIST;
    return o;
}

robj *createSetObject(void) {
    dict *d = dictCreate(&setDictType,NULL);
    robj *o = createObject(REDIS_SET,d);
    o->encoding = REDIS_ENCODING_HT;
    return o;
}

robj *createIntsetObject(void) {
    intset *is = intsetNew();
    robj *o = createObject(REDIS_SET,is);
    o->encoding = REDIS_ENCODING_INTSET;
    return o;
}

robj *createHashObject(void) {
    /* All the Hashes start as zipmaps. Will be automatically converted
     * into hash tables if there are enough elements or big elements
     * inside. */
    unsigned char *zm = zipmapNew();
    robj *o = createObject(REDIS_HASH,zm);
    o->encoding = REDIS_ENCODING_ZIPMAP;
    return o;
}

robj *createZsetObject(void) {
    zset *zs = zmalloc(sizeof(*zs));
    robj *o;

    zs->dict = dictCreate(&zsetDictType,NULL);
    zs->zsl = zslCreate();
    o = createObject(REDIS_ZSET,zs);
    o->encoding = REDIS_ENCODING_SKIPLIST;
    return o;
}

robj *createZsetZiplistObject(void) {
    unsigned char *zl = ziplistNew();
    robj *o = createObject(REDIS_ZSET,zl);
    o->encoding = REDIS_ENCODING_ZIPLIST;
    return o;
}

void freeStringObject(robj *o) {
    if (o->encoding == REDIS_ENCODING_RAW) {
        sdsfree(o->ptr);
    }
}

void freeListObject(robj *o) {
    switch (o->encoding) {
    case REDIS_ENCODING_LINKEDLIST:
        listRelease((list*) o->ptr);
        break;
    case REDIS_ENCODING_ZIPLIST:
        zfree(o->ptr);
        break;
    default:
        redisPanic("Unknown list encoding type");
    }
}

void freeSetObject(robj *o) {
    switch (o->encoding) {
    case REDIS_ENCODING_HT:
        dictRelease((dict*) o->ptr);
        break;
    case REDIS_ENCODING_INTSET:
        zfree(o->ptr);
        break;
    default:
        redisPanic("Unknown set encoding type");
    }
}

void freeZsetObject(robj *o) {
    zset *zs;
    switch (o->encoding) {
    case REDIS_ENCODING_SKIPLIST:
        zs = o->ptr;
        dictRelease(zs->dict);
        zslFree(zs->zsl);
        zfree(zs);
        break;
    case REDIS_ENCODING_ZIPLIST:
        zfree(o->ptr);
        break;
    default:
        redisPanic("Unknown sorted set encoding");
    }
}

void freeHashObject(robj *o) {
    switch (o->encoding) {
    case REDIS_ENCODING_HT:
        dictRelease((dict*) o->ptr);
        break;
    case REDIS_ENCODING_ZIPMAP:
        zfree(o->ptr);
        break;
    default:
        redisPanic("Unknown hash encoding type");
        break;
    }
}

void incrRefCount(robj *o) {
    o->refcount++;
}

void decrRefCount(void *obj) {
    robj *o = obj;

    if (o->refcount <= 0) redisPanic("decrRefCount against refcount <= 0");
    if (o->refcount == 1) {
        switch(o->type) {
        case REDIS_STRING: freeStringObject(o); break;
        case REDIS_LIST: freeListObject(o); break;
        case REDIS_SET: freeSetObject(o); break;
        case REDIS_ZSET: freeZsetObject(o); break;
        case REDIS_HASH: freeHashObject(o); break;
        default: redisPanic("Unknown object type"); break;
        }
        zfree(o);
    } else {
        o->refcount--;
    }
}

int checkType(redisClient *c, robj *o, int type) {
    if (o->type != type) {
        addReply(c,shared.wrongtypeerr);
        return 1;
    }
    return 0;
}

int isObjectRepresentableAsLongLong(robj *o, long long *llval) {
    redisAssert(o->type == REDIS_STRING);
    if (o->encoding == REDIS_ENCODING_INT) {
        if (llval) *llval = (long) o->ptr;
        return REDIS_OK;
    } else {
        return string2ll(o->ptr,sdslen(o->ptr),llval) ? REDIS_OK : REDIS_ERR;
    }
}

/* Try to encode a string object in order to save space */
robj *tryObjectEncoding(robj *o) {
    long value;
    sds s = o->ptr;

    if (o->encoding != REDIS_ENCODING_RAW)
        return o; /* Already encoded */

    /* It's not safe to encode shared objects: shared objects can be shared
     * everywhere in the "object space" of Redis. Encoded objects can only
     * appear as "values" (and not, for instance, as keys) */
     if (o->refcount > 1) return o;

    /* Currently we try to encode only strings */
    redisAssert(o->type == REDIS_STRING);

    /* Check if we can represent this string as a long integer */
    if (!string2l(s,sdslen(s),&value)) return o;

    /* Ok, this object can be encoded...
     *
     * Can I use a shared object? Only if the object is inside a given
     * range and if the back end in use is in-memory. For disk store every
     * object in memory used as value should be independent.
     *
     * Note that we also avoid using shared integers when maxmemory is used
     * because every object needs to have a private LRU field for the LRU
     * algorithm to work well. */
    if (server.maxmemory == 0 && value >= 0 && value < REDIS_SHARED_INTEGERS) {
        decrRefCount(o);
        incrRefCount(shared.integers[value]);
        return shared.integers[value];
    } else {
        o->encoding = REDIS_ENCODING_INT;
        sdsfree(o->ptr);
        o->ptr = (void*) value;
        return o;
    }
}

/* Get a decoded version of an encoded object (returned as a new object).
 * If the object is already raw-encoded just increment the ref count. */
robj *getDecodedObject(robj *o) {
    robj *dec;

    if (o->encoding == REDIS_ENCODING_RAW) {
        incrRefCount(o);
        return o;
    }
    if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
        char buf[32];

        ll2string(buf,32,(long)o->ptr);
        dec = createStringObject(buf,strlen(buf));
        return dec;
    } else {
        redisPanic("Unknown encoding type");
    }
}

/* Compare two string objects via strcmp() or alike.
 * Note that the objects may be integer-encoded. In such a case we
 * use ll2string() to get a string representation of the numbers on the stack
 * and compare the strings, it's much faster than calling getDecodedObject().
 *
 * Important note: if objects are not integer encoded, but binary-safe strings,
 * sdscmp() from sds.c will apply memcmp() so this function ca be considered
 * binary safe. */
int compareStringObjects(robj *a, robj *b) {
    redisAssert(a->type == REDIS_STRING && b->type == REDIS_STRING);
    char bufa[128], bufb[128], *astr, *bstr;
    int bothsds = 1;

    if (a == b) return 0;
    if (a->encoding != REDIS_ENCODING_RAW) {
        ll2string(bufa,sizeof(bufa),(long) a->ptr);
        astr = bufa;
        bothsds = 0;
    } else {
        astr = a->ptr;
    }
    if (b->encoding != REDIS_ENCODING_RAW) {
        ll2string(bufb,sizeof(bufb),(long) b->ptr);
        bstr = bufb;
        bothsds = 0;
    } else {
        bstr = b->ptr;
    }
    return bothsds ? sdscmp(astr,bstr) : strcmp(astr,bstr);
}

/* Equal string objects return 1 if the two objects are the same from the
 * point of view of a string comparison, otherwise 0 is returned. Note that
 * this function is faster then checking for (compareStringObject(a,b) == 0)
 * because it can perform some more optimization. */
int equalStringObjects(robj *a, robj *b) {
    if (a->encoding != REDIS_ENCODING_RAW && b->encoding != REDIS_ENCODING_RAW){
        return a->ptr == b->ptr;
    } else {
        return compareStringObjects(a,b) == 0;
    }
}

size_t stringObjectLen(robj *o) {
    redisAssert(o->type == REDIS_STRING);
    if (o->encoding == REDIS_ENCODING_RAW) {
        return sdslen(o->ptr);
    } else {
        char buf[32];

        return ll2string(buf,32,(long)o->ptr);
    }
}

int getDoubleFromObject(robj *o, double *target) {
    double value;
    char *eptr;

    if (o == NULL) {
        value = 0;
    } else {
        redisAssert(o->type == REDIS_STRING);
        if (o->encoding == REDIS_ENCODING_RAW) {
            value = strtod(o->ptr, &eptr);
            if (eptr[0] != '\0' || isnan(value)) return REDIS_ERR;
        } else if (o->encoding == REDIS_ENCODING_INT) {
            value = (long)o->ptr;
        } else {
            redisPanic("Unknown string encoding");
        }
    }

    *target = value;
    return REDIS_OK;
}

int getDoubleFromObjectOrReply(redisClient *c, robj *o, double *target, const char *msg) {
    double value;
    if (getDoubleFromObject(o, &value) != REDIS_OK) {
        if (msg != NULL) {
            addReplyError(c,(char*)msg);
        } else {
            addReplyError(c,"value is not a double");
        }
        return REDIS_ERR;
    }

    *target = value;
    return REDIS_OK;
}

int getLongLongFromObject(robj *o, long long *target) {
    long long value;
    char *eptr;

    if (o == NULL) {
        value = 0;
    } else {
        redisAssert(o->type == REDIS_STRING);
        if (o->encoding == REDIS_ENCODING_RAW) {
            value = strtoll(o->ptr, &eptr, 10);
            if (eptr[0] != '\0') return REDIS_ERR;
            if (errno == ERANGE && (value == LLONG_MIN || value == LLONG_MAX))
                return REDIS_ERR;
        } else if (o->encoding == REDIS_ENCODING_INT) {
            value = (long)o->ptr;
        } else {
            redisPanic("Unknown string encoding");
        }
    }

    if (target) *target = value;
    return REDIS_OK;
}

int getLongLongFromObjectOrReply(redisClient *c, robj *o, long long *target, const char *msg) {
    long long value;
    if (getLongLongFromObject(o, &value) != REDIS_OK) {
        if (msg != NULL) {
            addReplyError(c,(char*)msg);
        } else {
            addReplyError(c,"value is not an integer or out of range");
        }
        return REDIS_ERR;
    }

    *target = value;
    return REDIS_OK;
}

int getLongFromObjectOrReply(redisClient *c, robj *o, long *target, const char *msg) {
    long long value;

    if (getLongLongFromObjectOrReply(c, o, &value, msg) != REDIS_OK) return REDIS_ERR;
    if (value < LONG_MIN || value > LONG_MAX) {
        if (msg != NULL) {
            addReplyError(c,(char*)msg);
        } else {
            addReplyError(c,"value is out of range");
        }
        return REDIS_ERR;
    }

    *target = value;
    return REDIS_OK;
}

char *strEncoding(int encoding) {
    switch(encoding) {
    case REDIS_ENCODING_RAW: return "raw";
    case REDIS_ENCODING_INT: return "int";
    case REDIS_ENCODING_HT: return "hashtable";
    case REDIS_ENCODING_ZIPMAP: return "zipmap";
    case REDIS_ENCODING_LINKEDLIST: return "linkedlist";
    case REDIS_ENCODING_ZIPLIST: return "ziplist";
    case REDIS_ENCODING_INTSET: return "intset";
    case REDIS_ENCODING_SKIPLIST: return "skiplist";
    default: return "unknown";
    }
}

/* Given an object returns the min number of seconds the object was never
 * requested, using an approximated LRU algorithm. */
unsigned long estimateObjectIdleTime(robj *o) {
    if (server.lruclock >= o->lru) {
        return (server.lruclock - o->lru) * REDIS_LRU_CLOCK_RESOLUTION;
    } else {
        return ((REDIS_LRU_CLOCK_MAX - o->lru) + server.lruclock) *
                    REDIS_LRU_CLOCK_RESOLUTION;
    }
}

/* This is an helper function for the DEBUG command. We need to lookup keys
 * without any modification of LRU or other parameters. */
robj *objectCommandLookup(redisClient *c, robj *key) {
    dictEntry *de;

    if ((de = dictFind(c->db->dict,key->ptr)) == NULL) return NULL;
    return (robj*) dictGetEntryVal(de);
}

robj *objectCommandLookupOrReply(redisClient *c, robj *key, robj *reply) {
    robj *o = objectCommandLookup(c,key);

    if (!o) addReply(c, reply);
    return o;
}

/* Object command allows to inspect the internals of an Redis Object.
 * Usage: OBJECT <verb> ... arguments ... */
void objectCommand(redisClient *c) {
    robj *o;

    if (!strcasecmp(c->argv[1]->ptr,"refcount") && c->argc == 3) {
        if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
                == NULL) return;
        addReplyLongLong(c,o->refcount);
    } else if (!strcasecmp(c->argv[1]->ptr,"encoding") && c->argc == 3) {
        if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
                == NULL) return;
        addReplyBulkCString(c,strEncoding(o->encoding));
    } else if (!strcasecmp(c->argv[1]->ptr,"idletime") && c->argc == 3) {
        if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
                == NULL) return;
        addReplyLongLong(c,estimateObjectIdleTime(o));
    } else {
        addReplyError(c,"Syntax error. Try OBJECT (refcount|encoding|idletime)");
    }
}
Commit	Line	Data
e2641e09	1	#include "redis.h"
673e1fb7	2	#include <math.h>
e2641e09	3
e2641e09	4	robj createObject(int type, void ptr) {
a9b18e54	5	robj o = zmalloc(sizeof(o));
e2641e09	6	o->type = type;
	7	o->encoding = REDIS_ENCODING_RAW;
	8	o->ptr = ptr;
	9	o->refcount = 1;
a9b18e54	10
ef59a8bc	11	/* Set the LRU to the current lruclock (minutes resolution).
	12	* We do this regardless of the fact VM is active as LRU is also
	13	* used for the maxmemory directive when Redis is used as cache.
	14	*
	15	* Note that this code may run in the context of an I/O thread
	16	* and accessing server.lruclock in theory is an error
	17	* (no locks). But in practice this is safe, and even if we read
	18	* garbage Redis will not fail. */
	19	o->lru = server.lruclock;
	20	/* The following is only needed if VM is active, but since the conditional
	21	* is probably more costly than initializing the field it's better to
	22	* have every field properly initialized anyway. */
e2641e09	23	return o;
	24	}
	25
	26	robj createStringObject(char ptr, size_t len) {
	27	return createObject(REDIS_STRING,sdsnewlen(ptr,len));
	28	}
	29
	30	robj *createStringObjectFromLongLong(long long value) {
	31	robj *o;
c9d0c362	32	if (value >= 0 && value < REDIS_SHARED_INTEGERS) {
e2641e09	33	incrRefCount(shared.integers[value]);
	34	o = shared.integers[value];
	35	} else {
	36	if (value >= LONG_MIN && value <= LONG_MAX) {
	37	o = createObject(REDIS_STRING, NULL);
	38	o->encoding = REDIS_ENCODING_INT;
	39	o->ptr = (void*)((long)value);
	40	} else {
	41	o = createObject(REDIS_STRING,sdsfromlonglong(value));
	42	}
	43	}
	44	return o;
	45	}
	46
	47	robj dupStringObject(robj o) {
	48	redisAssert(o->encoding == REDIS_ENCODING_RAW);
	49	return createStringObject(o->ptr,sdslen(o->ptr));
	50	}
	51
	52	robj *createListObject(void) {
	53	list *l = listCreate();
	54	robj *o = createObject(REDIS_LIST,l);
	55	listSetFreeMethod(l,decrRefCount);
	56	o->encoding = REDIS_ENCODING_LINKEDLIST;
	57	return o;
	58	}
	59
	60	robj *createZiplistObject(void) {
	61	unsigned char *zl = ziplistNew();
	62	robj *o = createObject(REDIS_LIST,zl);
	63	o->encoding = REDIS_ENCODING_ZIPLIST;
	64	return o;
	65	}
	66
	67	robj *createSetObject(void) {
	68	dict *d = dictCreate(&setDictType,NULL);
96ffb2fe PN	69	robj *o = createObject(REDIS_SET,d);
	70	o->encoding = REDIS_ENCODING_HT;
	71	return o;
	72	}
	73
	74	robj *createIntsetObject(void) {
	75	intset *is = intsetNew();
	76	robj *o = createObject(REDIS_SET,is);
	77	o->encoding = REDIS_ENCODING_INTSET;
	78	return o;
e2641e09	79	}
	80
	81	robj *createHashObject(void) {
	82	/* All the Hashes start as zipmaps. Will be automatically converted
	83	* into hash tables if there are enough elements or big elements
	84	* inside. */
	85	unsigned char *zm = zipmapNew();
	86	robj *o = createObject(REDIS_HASH,zm);
	87	o->encoding = REDIS_ENCODING_ZIPMAP;
	88	return o;
	89	}
	90
	91	robj *createZsetObject(void) {
	92	zset zs = zmalloc(sizeof(zs));
0b7f6d09	93	robj *o;
e2641e09	94
	95	zs->dict = dictCreate(&zsetDictType,NULL);
	96	zs->zsl = zslCreate();
0b7f6d09	97	o = createObject(REDIS_ZSET,zs);
	98	o->encoding = REDIS_ENCODING_SKIPLIST;
	99	return o;
e2641e09	100	}
e2641e09	101
9e7cee0e PN	102	robj *createZsetZiplistObject(void) {
	103	unsigned char *zl = ziplistNew();
	104	robj *o = createObject(REDIS_ZSET,zl);
	105	o->encoding = REDIS_ENCODING_ZIPLIST;
	106	return o;
	107	}
	108
e2641e09	109	void freeStringObject(robj *o) {
	110	if (o->encoding == REDIS_ENCODING_RAW) {
	111	sdsfree(o->ptr);
	112	}
	113	}
	114
	115	void freeListObject(robj *o) {
	116	switch (o->encoding) {
	117	case REDIS_ENCODING_LINKEDLIST:
	118	listRelease((list*) o->ptr);
	119	break;
	120	case REDIS_ENCODING_ZIPLIST:
	121	zfree(o->ptr);
	122	break;
	123	default:
	124	redisPanic("Unknown list encoding type");
	125	}
	126	}
	127
	128	void freeSetObject(robj *o) {
96ffb2fe PN	129	switch (o->encoding) {
	130	case REDIS_ENCODING_HT:
	131	dictRelease((dict*) o->ptr);
	132	break;
	133	case REDIS_ENCODING_INTSET:
	134	zfree(o->ptr);
	135	break;
	136	default:
	137	redisPanic("Unknown set encoding type");
	138	}
e2641e09	139	}
	140
	141	void freeZsetObject(robj *o) {
0f23eb3b PN	142	zset *zs;
0f23eb3b PN	143	switch (o->encoding) {
100ed062	144	case REDIS_ENCODING_SKIPLIST:
0f23eb3b PN	145	zs = o->ptr;
	146	dictRelease(zs->dict);
	147	zslFree(zs->zsl);
	148	zfree(zs);
	149	break;
	150	case REDIS_ENCODING_ZIPLIST:
	151	zfree(o->ptr);
	152	break;
	153	default:
	154	redisPanic("Unknown sorted set encoding");
	155	}
e2641e09	156	}
	157
	158	void freeHashObject(robj *o) {
	159	switch (o->encoding) {
	160	case REDIS_ENCODING_HT:
	161	dictRelease((dict*) o->ptr);
	162	break;
	163	case REDIS_ENCODING_ZIPMAP:
	164	zfree(o->ptr);
	165	break;
	166	default:
	167	redisPanic("Unknown hash encoding type");
	168	break;
	169	}
	170	}
	171
	172	void incrRefCount(robj *o) {
	173	o->refcount++;
	174	}
	175
	176	void decrRefCount(void *obj) {
	177	robj *o = obj;
	178
e2641e09	179	if (o->refcount <= 0) redisPanic("decrRefCount against refcount <= 0");
936c4ab6	180	if (o->refcount == 1) {
e2641e09	181	switch(o->type) {
	182	case REDIS_STRING: freeStringObject(o); break;
	183	case REDIS_LIST: freeListObject(o); break;
	184	case REDIS_SET: freeSetObject(o); break;
	185	case REDIS_ZSET: freeZsetObject(o); break;
	186	case REDIS_HASH: freeHashObject(o); break;
	187	default: redisPanic("Unknown object type"); break;
	188	}
a9b18e54	189	zfree(o);
936c4ab6	190	} else {
936c4ab6	191	o->refcount--;
e2641e09	192	}
	193	}
	194
	195	int checkType(redisClient c, robj o, int type) {
	196	if (o->type != type) {
	197	addReply(c,shared.wrongtypeerr);
	198	return 1;
	199	}
	200	return 0;
	201	}
	202
5d081931 PN	203	int isObjectRepresentableAsLongLong(robj o, long long llval) {
	204	redisAssert(o->type == REDIS_STRING);
	205	if (o->encoding == REDIS_ENCODING_INT) {
	206	if (llval) *llval = (long) o->ptr;
	207	return REDIS_OK;
	208	} else {
	209	return string2ll(o->ptr,sdslen(o->ptr),llval) ? REDIS_OK : REDIS_ERR;
	210	}
	211	}
	212
e2641e09	213	/* Try to encode a string object in order to save space */
	214	robj tryObjectEncoding(robj o) {
	215	long value;
	216	sds s = o->ptr;
	217
	218	if (o->encoding != REDIS_ENCODING_RAW)
	219	return o; /* Already encoded */
	220
	221	/* It's not safe to encode shared objects: shared objects can be shared
	222	* everywhere in the "object space" of Redis. Encoded objects can only
	223	* appear as "values" (and not, for instance, as keys) */
	224	if (o->refcount > 1) return o;
	225
	226	/* Currently we try to encode only strings */
	227	redisAssert(o->type == REDIS_STRING);
	228
	229	/* Check if we can represent this string as a long integer */
5d081931	230	if (!string2l(s,sdslen(s),&value)) return o;
e2641e09	231
0e5441d8	232	/* Ok, this object can be encoded...
	233	*
	234	* Can I use a shared object? Only if the object is inside a given
cea8c5cd	235	* range and if the back end in use is in-memory. For disk store every
cea8c5cd	236	* object in memory used as value should be independent.
13a49af4	237	*
13a49af4	238	* Note that we also avoid using shared integers when maxmemory is used
cea8c5cd	239	* because every object needs to have a private LRU field for the LRU
13a49af4	240	* algorithm to work well. */
c9d0c362	241	if (server.maxmemory == 0 && value >= 0 && value < REDIS_SHARED_INTEGERS) {
e2641e09	242	decrRefCount(o);
	243	incrRefCount(shared.integers[value]);
	244	return shared.integers[value];
	245	} else {
	246	o->encoding = REDIS_ENCODING_INT;
	247	sdsfree(o->ptr);
	248	o->ptr = (void*) value;
	249	return o;
	250	}
	251	}
	252
	253	/* Get a decoded version of an encoded object (returned as a new object).
	254	* If the object is already raw-encoded just increment the ref count. */
	255	robj getDecodedObject(robj o) {
	256	robj *dec;
	257
	258	if (o->encoding == REDIS_ENCODING_RAW) {
	259	incrRefCount(o);
	260	return o;
	261	}
	262	if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
	263	char buf[32];
	264
	265	ll2string(buf,32,(long)o->ptr);
	266	dec = createStringObject(buf,strlen(buf));
	267	return dec;
	268	} else {
	269	redisPanic("Unknown encoding type");
	270	}
	271	}
	272
	273	/* Compare two string objects via strcmp() or alike.
	274	* Note that the objects may be integer-encoded. In such a case we
	275	* use ll2string() to get a string representation of the numbers on the stack
	276	* and compare the strings, it's much faster than calling getDecodedObject().
	277	*
	278	* Important note: if objects are not integer encoded, but binary-safe strings,
	279	* sdscmp() from sds.c will apply memcmp() so this function ca be considered
	280	* binary safe. */
	281	int compareStringObjects(robj a, robj b) {
	282	redisAssert(a->type == REDIS_STRING && b->type == REDIS_STRING);
	283	char bufa[128], bufb[128], astr, bstr;
	284	int bothsds = 1;
	285
	286	if (a == b) return 0;
	287	if (a->encoding != REDIS_ENCODING_RAW) {
	288	ll2string(bufa,sizeof(bufa),(long) a->ptr);
	289	astr = bufa;
	290	bothsds = 0;
	291	} else {
	292	astr = a->ptr;
	293	}
	294	if (b->encoding != REDIS_ENCODING_RAW) {
	295	ll2string(bufb,sizeof(bufb),(long) b->ptr);
	296	bstr = bufb;
	297	bothsds = 0;
	298	} else {
	299	bstr = b->ptr;
	300	}
	301	return bothsds ? sdscmp(astr,bstr) : strcmp(astr,bstr);
	302	}
	303
	304	/* Equal string objects return 1 if the two objects are the same from the
	305	* point of view of a string comparison, otherwise 0 is returned. Note that
306	* this function is faster then checking for (compareStringObject(a,b) == 0)
307	* because it can perform some more optimization. */
308	int equalStringObjects(robj a, robj b) {
309	if (a->encoding != REDIS_ENCODING_RAW && b->encoding != REDIS_ENCODING_RAW){
310	return a->ptr == b->ptr;
311	} else {
312	return compareStringObjects(a,b) == 0;
313	}
314	}
315
316	size_t stringObjectLen(robj *o) {
317	redisAssert(o->type == REDIS_STRING);
318	if (o->encoding == REDIS_ENCODING_RAW) {
319	return sdslen(o->ptr);
320	} else {
321	char buf[32];
322
323	return ll2string(buf,32,(long)o->ptr);
324	}
325	}
326
327	int getDoubleFromObject(robj o, double target) {
328	double value;
329	char *eptr;
330
331	if (o == NULL) {
332	value = 0;
333	} else {
334	redisAssert(o->type == REDIS_STRING);
335	if (o->encoding == REDIS_ENCODING_RAW) {
336	value = strtod(o->ptr, &eptr);
673e1fb7	337	if (eptr[0] != '\0' \|\| isnan(value)) return REDIS_ERR;
e2641e09	338	} else if (o->encoding == REDIS_ENCODING_INT) {
	339	value = (long)o->ptr;
	340	} else {
	341	redisPanic("Unknown string encoding");
	342	}
	343	}
	344
	345	*target = value;
	346	return REDIS_OK;
	347	}
	348
	349	int getDoubleFromObjectOrReply(redisClient c, robj o, double target, const char msg) {
	350	double value;
	351	if (getDoubleFromObject(o, &value) != REDIS_OK) {
	352	if (msg != NULL) {
3ab20376	353	addReplyError(c,(char*)msg);
e2641e09	354	} else {
3ab20376	355	addReplyError(c,"value is not a double");
e2641e09	356	}
	357	return REDIS_ERR;
	358	}
	359
	360	*target = value;
	361	return REDIS_OK;
	362	}
	363
	364	int getLongLongFromObject(robj o, long long target) {
	365	long long value;
	366	char *eptr;
	367
	368	if (o == NULL) {
	369	value = 0;
	370	} else {
	371	redisAssert(o->type == REDIS_STRING);
	372	if (o->encoding == REDIS_ENCODING_RAW) {
	373	value = strtoll(o->ptr, &eptr, 10);
	374	if (eptr[0] != '\0') return REDIS_ERR;
c91abdcd	375	if (errno == ERANGE && (value == LLONG_MIN \|\| value == LLONG_MAX))
c91abdcd	376	return REDIS_ERR;
e2641e09	377	} else if (o->encoding == REDIS_ENCODING_INT) {
	378	value = (long)o->ptr;
	379	} else {
	380	redisPanic("Unknown string encoding");
	381	}
	382	}
	383
96ffb2fe	384	if (target) *target = value;
e2641e09	385	return REDIS_OK;
	386	}
	387
	388	int getLongLongFromObjectOrReply(redisClient c, robj o, long long target, const char msg) {
	389	long long value;
	390	if (getLongLongFromObject(o, &value) != REDIS_OK) {
	391	if (msg != NULL) {
3ab20376	392	addReplyError(c,(char*)msg);
e2641e09	393	} else {
3ab20376	394	addReplyError(c,"value is not an integer or out of range");
e2641e09	395	}
	396	return REDIS_ERR;
	397	}
	398
	399	*target = value;
	400	return REDIS_OK;
	401	}
	402
	403	int getLongFromObjectOrReply(redisClient c, robj o, long target, const char msg) {
	404	long long value;
	405
	406	if (getLongLongFromObjectOrReply(c, o, &value, msg) != REDIS_OK) return REDIS_ERR;
	407	if (value < LONG_MIN \|\| value > LONG_MAX) {
	408	if (msg != NULL) {
3ab20376	409	addReplyError(c,(char*)msg);
e2641e09	410	} else {
3ab20376	411	addReplyError(c,"value is out of range");
e2641e09	412	}
	413	return REDIS_ERR;
	414	}
	415
	416	*target = value;
	417	return REDIS_OK;
	418	}
	419
	420	char *strEncoding(int encoding) {
	421	switch(encoding) {
	422	case REDIS_ENCODING_RAW: return "raw";
	423	case REDIS_ENCODING_INT: return "int";
	424	case REDIS_ENCODING_HT: return "hashtable";
	425	case REDIS_ENCODING_ZIPMAP: return "zipmap";
	426	case REDIS_ENCODING_LINKEDLIST: return "linkedlist";
	427	case REDIS_ENCODING_ZIPLIST: return "ziplist";
96ffb2fe	428	case REDIS_ENCODING_INTSET: return "intset";
0b7f6d09	429	case REDIS_ENCODING_SKIPLIST: return "skiplist";
e2641e09	430	default: return "unknown";
	431	}
	432	}
ef59a8bc	433
	434	/* Given an object returns the min number of seconds the object was never
	435	* requested, using an approximated LRU algorithm. */
	436	unsigned long estimateObjectIdleTime(robj *o) {
	437	if (server.lruclock >= o->lru) {
165346ca	438	return (server.lruclock - o->lru) * REDIS_LRU_CLOCK_RESOLUTION;
ef59a8bc	439	} else {
165346ca	440	return ((REDIS_LRU_CLOCK_MAX - o->lru) + server.lruclock) *
165346ca	441	REDIS_LRU_CLOCK_RESOLUTION;
ef59a8bc	442	}
ef59a8bc	443	}
ece74202	444
	445	/* This is an helper function for the DEBUG command. We need to lookup keys
	446	* without any modification of LRU or other parameters. */
	447	robj objectCommandLookup(redisClient c, robj *key) {
	448	dictEntry *de;
	449
	450	if ((de = dictFind(c->db->dict,key->ptr)) == NULL) return NULL;
	451	return (robj*) dictGetEntryVal(de);
	452	}
	453
	454	robj objectCommandLookupOrReply(redisClient c, robj key, robj reply) {
	455	robj *o = objectCommandLookup(c,key);
	456
	457	if (!o) addReply(c, reply);
	458	return o;
	459	}
	460
	461	/* Object command allows to inspect the internals of an Redis Object.
	462	* Usage: OBJECT <verb> ... arguments ... */
	463	void objectCommand(redisClient *c) {
	464	robj *o;
	465
	466	if (!strcasecmp(c->argv[1]->ptr,"refcount") && c->argc == 3) {
	467	if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
	468	== NULL) return;
	469	addReplyLongLong(c,o->refcount);
	470	} else if (!strcasecmp(c->argv[1]->ptr,"encoding") && c->argc == 3) {
	471	if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
	472	== NULL) return;
	473	addReplyBulkCString(c,strEncoding(o->encoding));
	474	} else if (!strcasecmp(c->argv[1]->ptr,"idletime") && c->argc == 3) {
	475	if ((o = objectCommandLookupOrReply(c,c->argv[2],shared.nullbulk))
	476	== NULL) return;
	477	addReplyLongLong(c,estimateObjectIdleTime(o));
	478	} else {
	479	addReplyError(c,"Syntax error. Try OBJECT (refcount\|encoding\|idletime)");
	480	}
	481	}
	482