[redis.git] / src / object.c

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

robj *createObject(int type, void *ptr) {
    robj *o;

    if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
    if (listLength(server.objfreelist)) {
        listNode *head = listFirst(server.objfreelist);
        o = listNodeValue(head);
        listDelNode(server.objfreelist,head);
        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
    } else {
        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
        o = zmalloc(sizeof(*o));
    }
    o->type = type;
    o->encoding = REDIS_ENCODING_RAW;
    o->ptr = ptr;
    o->refcount = 1;
    if (server.vm_enabled) {
        /* 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;
        o->storage = REDIS_VM_MEMORY;
    }
    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 &&
        pthread_equal(pthread_self(),server.mainthread)) {
        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));

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

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 = o->ptr;

    dictRelease(zs->dict);
    zslFree(zs->zsl);
    zfree(zs);
}

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;

    /* Object is a swapped out value, or in the process of being loaded. */
    if (server.vm_enabled &&
        (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING))
    {
        vmpointer *vp = obj;
        if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(o);
        vmMarkPagesFree(vp->page,vp->usedpages);
        server.vm_stats_swapped_objects--;
        zfree(vp);
        return;
    }

    if (o->refcount <= 0) redisPanic("decrRefCount against refcount <= 0");
    /* Object is in memory, or in the process of being swapped out.
     *
     * If the object is being swapped out, abort the operation on
     * decrRefCount even if the refcount does not drop to 0: the object
     * is referenced at least two times, as value of the key AND as
     * job->val in the iojob. So if we don't invalidate the iojob, when it is
     * done but the relevant key was removed in the meantime, the
     * complete jobs handler will not find the key about the job and the
     * assert will fail. */
    if (server.vm_enabled && o->storage == REDIS_VM_SWAPPING)
        vmCancelThreadedIOJob(o);
    if (--(o->refcount) == 0) {
        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;
        }
        o->ptr = NULL; /* defensive programming. We'll see NULL in traces. */
        if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
        if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX ||
            !listAddNodeHead(server.objfreelist,o))
            zfree(o);
        if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
    }
}

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

/* 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 (isStringRepresentableAsLong(s,&value) == REDIS_ERR) 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 this is the main thread, since when VM is enabled we
     * have the constraint that I/O thread should only handle non-shared
     * objects, in order to avoid race conditions (we don't have per-object
     * locking). */
    if (value >= 0 && value < REDIS_SHARED_INTEGERS &&
        pthread_equal(pthread_self(),server.mainthread)) {
        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";
    default: return "unknown";
    }
}
Commit	Line	Data
e2641e09	1	#include "redis.h"
e2641e09	2	#include <pthread.h>
673e1fb7	3	#include <math.h>
e2641e09	4
	5	robj createObject(int type, void ptr) {
	6	robj *o;
	7
	8	if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
	9	if (listLength(server.objfreelist)) {
	10	listNode *head = listFirst(server.objfreelist);
	11	o = listNodeValue(head);
	12	listDelNode(server.objfreelist,head);
	13	if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
	14	} else {
2cffe299	15	if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
e2641e09	16	o = zmalloc(sizeof(*o));
	17	}
	18	o->type = type;
	19	o->encoding = REDIS_ENCODING_RAW;
	20	o->ptr = ptr;
	21	o->refcount = 1;
	22	if (server.vm_enabled) {
	23	/* Note that this code may run in the context of an I/O thread
	24	* and accessing server.lruclock in theory is an error
	25	* (no locks). But in practice this is safe, and even if we read
	26	* garbage Redis will not fail. */
	27	o->lru = server.lruclock;
	28	o->storage = REDIS_VM_MEMORY;
	29	}
	30	return o;
	31	}
	32
	33	robj createStringObject(char ptr, size_t len) {
	34	return createObject(REDIS_STRING,sdsnewlen(ptr,len));
	35	}
	36
	37	robj *createStringObjectFromLongLong(long long value) {
	38	robj *o;
e002ec68	39	if (value >= 0 && value < REDIS_SHARED_INTEGERS &&
e002ec68	40	pthread_equal(pthread_self(),server.mainthread)) {
e2641e09	41	incrRefCount(shared.integers[value]);
	42	o = shared.integers[value];
	43	} else {
	44	if (value >= LONG_MIN && value <= LONG_MAX) {
	45	o = createObject(REDIS_STRING, NULL);
	46	o->encoding = REDIS_ENCODING_INT;
	47	o->ptr = (void*)((long)value);
	48	} else {
	49	o = createObject(REDIS_STRING,sdsfromlonglong(value));
	50	}
	51	}
	52	return o;
	53	}
	54
	55	robj dupStringObject(robj o) {
	56	redisAssert(o->encoding == REDIS_ENCODING_RAW);
	57	return createStringObject(o->ptr,sdslen(o->ptr));
	58	}
	59
	60	robj *createListObject(void) {
	61	list *l = listCreate();
	62	robj *o = createObject(REDIS_LIST,l);
	63	listSetFreeMethod(l,decrRefCount);
	64	o->encoding = REDIS_ENCODING_LINKEDLIST;
	65	return o;
	66	}
	67
	68	robj *createZiplistObject(void) {
	69	unsigned char *zl = ziplistNew();
	70	robj *o = createObject(REDIS_LIST,zl);
	71	o->encoding = REDIS_ENCODING_ZIPLIST;
	72	return o;
	73	}
	74
	75	robj *createSetObject(void) {
	76	dict *d = dictCreate(&setDictType,NULL);
96ffb2fe PN	77	robj *o = createObject(REDIS_SET,d);
	78	o->encoding = REDIS_ENCODING_HT;
	79	return o;
	80	}
	81
	82	robj *createIntsetObject(void) {
	83	intset *is = intsetNew();
	84	robj *o = createObject(REDIS_SET,is);
	85	o->encoding = REDIS_ENCODING_INTSET;
	86	return o;
e2641e09	87	}
	88
	89	robj *createHashObject(void) {
	90	/* All the Hashes start as zipmaps. Will be automatically converted
	91	* into hash tables if there are enough elements or big elements
	92	* inside. */
	93	unsigned char *zm = zipmapNew();
	94	robj *o = createObject(REDIS_HASH,zm);
	95	o->encoding = REDIS_ENCODING_ZIPMAP;
	96	return o;
	97	}
	98
	99	robj *createZsetObject(void) {
	100	zset zs = zmalloc(sizeof(zs));
	101
	102	zs->dict = dictCreate(&zsetDictType,NULL);
	103	zs->zsl = zslCreate();
	104	return createObject(REDIS_ZSET,zs);
	105	}
	106
	107	void freeStringObject(robj *o) {
	108	if (o->encoding == REDIS_ENCODING_RAW) {
	109	sdsfree(o->ptr);
	110	}
	111	}
	112
	113	void freeListObject(robj *o) {
	114	switch (o->encoding) {
	115	case REDIS_ENCODING_LINKEDLIST:
	116	listRelease((list*) o->ptr);
	117	break;
	118	case REDIS_ENCODING_ZIPLIST:
	119	zfree(o->ptr);
	120	break;
	121	default:
	122	redisPanic("Unknown list encoding type");
	123	}
	124	}
	125
	126	void freeSetObject(robj *o) {
96ffb2fe PN	127	switch (o->encoding) {
	128	case REDIS_ENCODING_HT:
	129	dictRelease((dict*) o->ptr);
	130	break;
	131	case REDIS_ENCODING_INTSET:
	132	zfree(o->ptr);
	133	break;
	134	default:
	135	redisPanic("Unknown set encoding type");
	136	}
e2641e09	137	}
	138
	139	void freeZsetObject(robj *o) {
	140	zset *zs = o->ptr;
	141
	142	dictRelease(zs->dict);
	143	zslFree(zs->zsl);
	144	zfree(zs);
	145	}
	146
	147	void freeHashObject(robj *o) {
	148	switch (o->encoding) {
	149	case REDIS_ENCODING_HT:
	150	dictRelease((dict*) o->ptr);
	151	break;
	152	case REDIS_ENCODING_ZIPMAP:
	153	zfree(o->ptr);
	154	break;
	155	default:
	156	redisPanic("Unknown hash encoding type");
	157	break;
	158	}
	159	}
	160
	161	void incrRefCount(robj *o) {
	162	o->refcount++;
	163	}
	164
	165	void decrRefCount(void *obj) {
	166	robj *o = obj;
	167
	168	/* Object is a swapped out value, or in the process of being loaded. */
	169	if (server.vm_enabled &&
	170	(o->storage == REDIS_VM_SWAPPED \|\| o->storage == REDIS_VM_LOADING))
	171	{
	172	vmpointer *vp = obj;
	173	if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(o);
	174	vmMarkPagesFree(vp->page,vp->usedpages);
	175	server.vm_stats_swapped_objects--;
	176	zfree(vp);
	177	return;
	178	}
	179
	180	if (o->refcount <= 0) redisPanic("decrRefCount against refcount <= 0");
	181	/* Object is in memory, or in the process of being swapped out.
	182	*
	183	* If the object is being swapped out, abort the operation on
	184	* decrRefCount even if the refcount does not drop to 0: the object
	185	* is referenced at least two times, as value of the key AND as
	186	* job->val in the iojob. So if we don't invalidate the iojob, when it is
	187	* done but the relevant key was removed in the meantime, the
	188	* complete jobs handler will not find the key about the job and the
	189	* assert will fail. */
	190	if (server.vm_enabled && o->storage == REDIS_VM_SWAPPING)
	191	vmCancelThreadedIOJob(o);
	192	if (--(o->refcount) == 0) {
	193	switch(o->type) {
	194	case REDIS_STRING: freeStringObject(o); break;
	195	case REDIS_LIST: freeListObject(o); break;
	196	case REDIS_SET: freeSetObject(o); break;
	197	case REDIS_ZSET: freeZsetObject(o); break;
	198	case REDIS_HASH: freeHashObject(o); break;
	199	default: redisPanic("Unknown object type"); break;
	200	}
2f996f02	201	o->ptr = NULL; /* defensive programming. We'll see NULL in traces. */
e2641e09	202	if (server.vm_enabled) pthread_mutex_lock(&server.obj_freelist_mutex);
	203	if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX \|\|
	204	!listAddNodeHead(server.objfreelist,o))
	205	zfree(o);
	206	if (server.vm_enabled) pthread_mutex_unlock(&server.obj_freelist_mutex);
	207	}
	208	}
	209
	210	int checkType(redisClient c, robj o, int type) {
	211	if (o->type != type) {
	212	addReply(c,shared.wrongtypeerr);
	213	return 1;
	214	}
	215	return 0;
	216	}
	217
	218	/* Try to encode a string object in order to save space */
	219	robj tryObjectEncoding(robj o) {
	220	long value;
	221	sds s = o->ptr;
	222
	223	if (o->encoding != REDIS_ENCODING_RAW)
	224	return o; /* Already encoded */
	225
	226	/* It's not safe to encode shared objects: shared objects can be shared
	227	* everywhere in the "object space" of Redis. Encoded objects can only
	228	* appear as "values" (and not, for instance, as keys) */
	229	if (o->refcount > 1) return o;
	230
	231	/* Currently we try to encode only strings */
	232	redisAssert(o->type == REDIS_STRING);
	233
	234	/* Check if we can represent this string as a long integer */
	235	if (isStringRepresentableAsLong(s,&value) == REDIS_ERR) return o;
	236
0e5441d8	237	/* Ok, this object can be encoded...
	238	*
	239	* Can I use a shared object? Only if the object is inside a given
cdbea20a	240	* range and if this is the main thread, since when VM is enabled we
0e5441d8	241	* have the constraint that I/O thread should only handle non-shared
	242	* objects, in order to avoid race conditions (we don't have per-object
	243	* locking). */
	244	if (value >= 0 && value < REDIS_SHARED_INTEGERS &&
	245	pthread_equal(pthread_self(),server.mainthread)) {
e2641e09	246	decrRefCount(o);
	247	incrRefCount(shared.integers[value]);
	248	return shared.integers[value];
	249	} else {
	250	o->encoding = REDIS_ENCODING_INT;
	251	sdsfree(o->ptr);
	252	o->ptr = (void*) value;
	253	return o;
	254	}
	255	}
	256
	257	/* Get a decoded version of an encoded object (returned as a new object).
	258	* If the object is already raw-encoded just increment the ref count. */
	259	robj getDecodedObject(robj o) {
	260	robj *dec;
	261
	262	if (o->encoding == REDIS_ENCODING_RAW) {
	263	incrRefCount(o);
	264	return o;
	265	}
	266	if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
	267	char buf[32];
	268
	269	ll2string(buf,32,(long)o->ptr);
	270	dec = createStringObject(buf,strlen(buf));
	271	return dec;
	272	} else {
	273	redisPanic("Unknown encoding type");
	274	}
	275	}
	276
	277	/* Compare two string objects via strcmp() or alike.
	278	* Note that the objects may be integer-encoded. In such a case we
	279	* use ll2string() to get a string representation of the numbers on the stack
	280	* and compare the strings, it's much faster than calling getDecodedObject().
	281	*
	282	* Important note: if objects are not integer encoded, but binary-safe strings,
	283	* sdscmp() from sds.c will apply memcmp() so this function ca be considered
	284	* binary safe. */
	285	int compareStringObjects(robj a, robj b) {
	286	redisAssert(a->type == REDIS_STRING && b->type == REDIS_STRING);
	287	char bufa[128], bufb[128], astr, bstr;
	288	int bothsds = 1;
	289
	290	if (a == b) return 0;
	291	if (a->encoding != REDIS_ENCODING_RAW) {
	292	ll2string(bufa,sizeof(bufa),(long) a->ptr);
	293	astr = bufa;
	294	bothsds = 0;
	295	} else {
	296	astr = a->ptr;
	297	}
	298	if (b->encoding != REDIS_ENCODING_RAW) {
	299	ll2string(bufb,sizeof(bufb),(long) b->ptr);
	300	bstr = bufb;
	301	bothsds = 0;
	302	} else {
	303	bstr = b->ptr;
	304	}
	305	return bothsds ? sdscmp(astr,bstr) : strcmp(astr,bstr);
	306	}
	307
	308	/* Equal string objects return 1 if the two objects are the same from the
	309	* point of view of a string comparison, otherwise 0 is returned. Note that
310	* this function is faster then checking for (compareStringObject(a,b) == 0)
311	* because it can perform some more optimization. */
312	int equalStringObjects(robj a, robj b) {
313	if (a->encoding != REDIS_ENCODING_RAW && b->encoding != REDIS_ENCODING_RAW){
314	return a->ptr == b->ptr;
315	} else {
316	return compareStringObjects(a,b) == 0;
317	}
318	}
319
320	size_t stringObjectLen(robj *o) {
321	redisAssert(o->type == REDIS_STRING);
322	if (o->encoding == REDIS_ENCODING_RAW) {
323	return sdslen(o->ptr);
324	} else {
325	char buf[32];
326
327	return ll2string(buf,32,(long)o->ptr);
328	}
329	}
330
331	int getDoubleFromObject(robj o, double target) {
332	double value;
333	char *eptr;
334
335	if (o == NULL) {
336	value = 0;
337	} else {
338	redisAssert(o->type == REDIS_STRING);
339	if (o->encoding == REDIS_ENCODING_RAW) {
340	value = strtod(o->ptr, &eptr);
673e1fb7	341	if (eptr[0] != '\0' \|\| isnan(value)) return REDIS_ERR;
e2641e09	342	} else if (o->encoding == REDIS_ENCODING_INT) {
	343	value = (long)o->ptr;
	344	} else {
	345	redisPanic("Unknown string encoding");
	346	}
	347	}
	348
	349	*target = value;
	350	return REDIS_OK;
	351	}
	352
	353	int getDoubleFromObjectOrReply(redisClient c, robj o, double target, const char msg) {
	354	double value;
	355	if (getDoubleFromObject(o, &value) != REDIS_OK) {
	356	if (msg != NULL) {
3ab20376	357	addReplyError(c,(char*)msg);
e2641e09	358	} else {
3ab20376	359	addReplyError(c,"value is not a double");
e2641e09	360	}
	361	return REDIS_ERR;
	362	}
	363
	364	*target = value;
	365	return REDIS_OK;
	366	}
	367
	368	int getLongLongFromObject(robj o, long long target) {
	369	long long value;
	370	char *eptr;
	371
	372	if (o == NULL) {
	373	value = 0;
	374	} else {
	375	redisAssert(o->type == REDIS_STRING);
	376	if (o->encoding == REDIS_ENCODING_RAW) {
	377	value = strtoll(o->ptr, &eptr, 10);
	378	if (eptr[0] != '\0') return REDIS_ERR;
c91abdcd	379	if (errno == ERANGE && (value == LLONG_MIN \|\| value == LLONG_MAX))
c91abdcd	380	return REDIS_ERR;
e2641e09	381	} else if (o->encoding == REDIS_ENCODING_INT) {
	382	value = (long)o->ptr;
	383	} else {
	384	redisPanic("Unknown string encoding");
	385	}
	386	}
	387
96ffb2fe	388	if (target) *target = value;
e2641e09	389	return REDIS_OK;
	390	}
	391
	392	int getLongLongFromObjectOrReply(redisClient c, robj o, long long target, const char msg) {
	393	long long value;
	394	if (getLongLongFromObject(o, &value) != REDIS_OK) {
	395	if (msg != NULL) {
3ab20376	396	addReplyError(c,(char*)msg);
e2641e09	397	} else {
3ab20376	398	addReplyError(c,"value is not an integer or out of range");
e2641e09	399	}
	400	return REDIS_ERR;
	401	}
	402
	403	*target = value;
	404	return REDIS_OK;
	405	}
	406
	407	int getLongFromObjectOrReply(redisClient c, robj o, long target, const char msg) {
	408	long long value;
	409
	410	if (getLongLongFromObjectOrReply(c, o, &value, msg) != REDIS_OK) return REDIS_ERR;
	411	if (value < LONG_MIN \|\| value > LONG_MAX) {
	412	if (msg != NULL) {
3ab20376	413	addReplyError(c,(char*)msg);
e2641e09	414	} else {
3ab20376	415	addReplyError(c,"value is out of range");
e2641e09	416	}
	417	return REDIS_ERR;
	418	}
	419
	420	*target = value;
	421	return REDIS_OK;
	422	}
	423
	424	char *strEncoding(int encoding) {
	425	switch(encoding) {
	426	case REDIS_ENCODING_RAW: return "raw";
	427	case REDIS_ENCODING_INT: return "int";
	428	case REDIS_ENCODING_HT: return "hashtable";
	429	case REDIS_ENCODING_ZIPMAP: return "zipmap";
	430	case REDIS_ENCODING_LINKEDLIST: return "linkedlist";
	431	case REDIS_ENCODING_ZIPLIST: return "ziplist";
96ffb2fe	432	case REDIS_ENCODING_INTSET: return "intset";
e2641e09	433	default: return "unknown";
	434	}
	435	}