[redis.git] / src / debug.c

#include "redis.h"
#include "sha1.h"   /* SHA1 is used for DEBUG DIGEST */

#include <arpa/inet.h>

/* ================================= Debugging ============================== */

/* Compute the sha1 of string at 's' with 'len' bytes long.
 * The SHA1 is then xored againt the string pointed by digest.
 * Since xor is commutative, this operation is used in order to
 * "add" digests relative to unordered elements.
 *
 * So digest(a,b,c,d) will be the same of digest(b,a,c,d) */
void xorDigest(unsigned char *digest, void *ptr, size_t len) {
    SHA1_CTX ctx;
    unsigned char hash[20], *s = ptr;
    int j;

    SHA1Init(&ctx);
    SHA1Update(&ctx,s,len);
    SHA1Final(hash,&ctx);

    for (j = 0; j < 20; j++)
        digest[j] ^= hash[j];
}

void xorObjectDigest(unsigned char *digest, robj *o) {
    o = getDecodedObject(o);
    xorDigest(digest,o->ptr,sdslen(o->ptr));
    decrRefCount(o);
}

/* This function instead of just computing the SHA1 and xoring it
 * against diget, also perform the digest of "digest" itself and
 * replace the old value with the new one.
 *
 * So the final digest will be:
 *
 * digest = SHA1(digest xor SHA1(data))
 *
 * This function is used every time we want to preserve the order so
 * that digest(a,b,c,d) will be different than digest(b,c,d,a)
 *
 * Also note that mixdigest("foo") followed by mixdigest("bar")
 * will lead to a different digest compared to "fo", "obar".
 */
void mixDigest(unsigned char *digest, void *ptr, size_t len) {
    SHA1_CTX ctx;
    char *s = ptr;

    xorDigest(digest,s,len);
    SHA1Init(&ctx);
    SHA1Update(&ctx,digest,20);
    SHA1Final(digest,&ctx);
}

void mixObjectDigest(unsigned char *digest, robj *o) {
    o = getDecodedObject(o);
    mixDigest(digest,o->ptr,sdslen(o->ptr));
    decrRefCount(o);
}

/* Compute the dataset digest. Since keys, sets elements, hashes elements
 * are not ordered, we use a trick: every aggregate digest is the xor
 * of the digests of their elements. This way the order will not change
 * the result. For list instead we use a feedback entering the output digest
 * as input in order to ensure that a different ordered list will result in
 * a different digest. */
void computeDatasetDigest(unsigned char *final) {
    unsigned char digest[20];
    char buf[128];
    dictIterator *di = NULL;
    dictEntry *de;
    int j;
    uint32_t aux;

    memset(final,0,20); /* Start with a clean result */

    for (j = 0; j < server.dbnum; j++) {
        redisDb *db = server.db+j;

        if (dictSize(db->dict) == 0) continue;
        di = dictGetIterator(db->dict);

        /* hash the DB id, so the same dataset moved in a different
         * DB will lead to a different digest */
        aux = htonl(j);
        mixDigest(final,&aux,sizeof(aux));

        /* Iterate this DB writing every entry */
        while((de = dictNext(di)) != NULL) {
            sds key;
            robj *keyobj, *o;
            time_t expiretime;

            memset(digest,0,20); /* This key-val digest */
            key = dictGetEntryKey(de);
            keyobj = createStringObject(key,sdslen(key));

            mixDigest(digest,key,sdslen(key));

            /* Make sure the key is loaded if VM is active */
            o = lookupKeyRead(db,keyobj);

            aux = htonl(o->type);
            mixDigest(digest,&aux,sizeof(aux));
            expiretime = getExpire(db,keyobj);

            /* Save the key and associated value */
            if (o->type == REDIS_STRING) {
                mixObjectDigest(digest,o);
            } else if (o->type == REDIS_LIST) {
                listTypeIterator *li = listTypeInitIterator(o,0,REDIS_TAIL);
                listTypeEntry entry;
                while(listTypeNext(li,&entry)) {
                    robj *eleobj = listTypeGet(&entry);
                    mixObjectDigest(digest,eleobj);
                    decrRefCount(eleobj);
                }
                listTypeReleaseIterator(li);
            } else if (o->type == REDIS_SET) {
                setTypeIterator *si = setTypeInitIterator(o);
                robj *ele;
                while((ele = setTypeNextObject(si)) != NULL) {
                    xorObjectDigest(digest,ele);
                    decrRefCount(ele);
                }
                setTypeReleaseIterator(si);
            } else if (o->type == REDIS_ZSET) {
                zset *zs = o->ptr;
                dictIterator *di = dictGetIterator(zs->dict);
                dictEntry *de;

                while((de = dictNext(di)) != NULL) {
                    robj *eleobj = dictGetEntryKey(de);
                    double *score = dictGetEntryVal(de);
                    unsigned char eledigest[20];

                    snprintf(buf,sizeof(buf),"%.17g",*score);
                    memset(eledigest,0,20);
                    mixObjectDigest(eledigest,eleobj);
                    mixDigest(eledigest,buf,strlen(buf));
                    xorDigest(digest,eledigest,20);
                }
                dictReleaseIterator(di);
            } else if (o->type == REDIS_HASH) {
                hashTypeIterator *hi;
                robj *obj;

                hi = hashTypeInitIterator(o);
                while (hashTypeNext(hi) != REDIS_ERR) {
                    unsigned char eledigest[20];

                    memset(eledigest,0,20);
                    obj = hashTypeCurrentObject(hi,REDIS_HASH_KEY);
                    mixObjectDigest(eledigest,obj);
                    decrRefCount(obj);
                    obj = hashTypeCurrentObject(hi,REDIS_HASH_VALUE);
                    mixObjectDigest(eledigest,obj);
                    decrRefCount(obj);
                    xorDigest(digest,eledigest,20);
                }
                hashTypeReleaseIterator(hi);
            } else {
                redisPanic("Unknown object type");
            }
            /* If the key has an expire, add it to the mix */
            if (expiretime != -1) xorDigest(digest,"!!expire!!",10);
            /* We can finally xor the key-val digest to the final digest */
            xorDigest(final,digest,20);
            decrRefCount(keyobj);
        }
        dictReleaseIterator(di);
    }
}

void debugCommand(redisClient *c) {
    if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
        *((char*)-1) = 'x';
    } else if (!strcasecmp(c->argv[1]->ptr,"reload")) {
        if (rdbSave(server.dbfilename) != REDIS_OK) {
            addReply(c,shared.err);
            return;
        }
        emptyDb();
        if (rdbLoad(server.dbfilename) != REDIS_OK) {
            addReply(c,shared.err);
            return;
        }
        redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD");
        addReply(c,shared.ok);
    } else if (!strcasecmp(c->argv[1]->ptr,"loadaof")) {
        emptyDb();
        if (loadAppendOnlyFile(server.appendfilename) != REDIS_OK) {
            addReply(c,shared.err);
            return;
        }
        redisLog(REDIS_WARNING,"Append Only File loaded by DEBUG LOADAOF");
        addReply(c,shared.ok);
    } else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) {
        dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
        robj *val;
        char *strenc;

        if (!de) {
            addReply(c,shared.nokeyerr);
            return;
        }
        val = dictGetEntryVal(de);
        strenc = strEncoding(val->encoding);

        addReplyStatusFormat(c,
            "Value at:%p refcount:%d "
            "encoding:%s serializedlength:%lld "
            "lru:%d lru_seconds_idle:%lu",
            (void*)val, val->refcount,
            strenc, (long long) rdbSavedObjectLen(val),
            val->lru, estimateObjectIdleTime(val));
    } else if (!strcasecmp(c->argv[1]->ptr,"populate") && c->argc == 3) {
        long keys, j;
        robj *key, *val;
        char buf[128];

        if (getLongFromObjectOrReply(c, c->argv[2], &keys, NULL) != REDIS_OK)
            return;
        for (j = 0; j < keys; j++) {
            snprintf(buf,sizeof(buf),"key:%lu",j);
            key = createStringObject(buf,strlen(buf));
            if (lookupKeyRead(c->db,key) != NULL) {
                decrRefCount(key);
                continue;
            }
            snprintf(buf,sizeof(buf),"value:%lu",j);
            val = createStringObject(buf,strlen(buf));
            dbAdd(c->db,key,val);
            decrRefCount(key);
        }
        addReply(c,shared.ok);
    } else if (!strcasecmp(c->argv[1]->ptr,"digest") && c->argc == 2) {
        unsigned char digest[20];
        sds d = sdsempty();
        int j;

        computeDatasetDigest(digest);
        for (j = 0; j < 20; j++)
            d = sdscatprintf(d, "%02x",digest[j]);
        addReplyStatus(c,d);
        sdsfree(d);
    } else {
        addReplyError(c,
            "Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|SWAPIN <key>|SWAPOUT <key>|RELOAD]");
    }
}

void _redisAssert(char *estr, char *file, int line) {
    redisLog(REDIS_WARNING,"=== ASSERTION FAILED ===");
    redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true",file,line,estr);
#ifdef HAVE_BACKTRACE
    redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
    *((char*)-1) = 'x';
#endif
}

void _redisPanic(char *msg, char *file, int line) {
    redisLog(REDIS_WARNING,"------------------------------------------------");
    redisLog(REDIS_WARNING,"!!! Software Failure. Press left mouse button to continue");
    redisLog(REDIS_WARNING,"Guru Meditation: %s #%s:%d",msg,file,line);
#ifdef HAVE_BACKTRACE
    redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
    redisLog(REDIS_WARNING,"------------------------------------------------");
    *((char*)-1) = 'x';
#endif
}
Commit	Line	Data
e2641e09	1	#include "redis.h"
	2	#include "sha1.h" /* SHA1 is used for DEBUG DIGEST */
	3
3688d7f3	4	#include <arpa/inet.h>
3688d7f3	5
e2641e09	6	/* ================================= Debugging ============================== */
	7
	8	/* Compute the sha1 of string at 's' with 'len' bytes long.
	9	* The SHA1 is then xored againt the string pointed by digest.
	10	* Since xor is commutative, this operation is used in order to
	11	* "add" digests relative to unordered elements.
	12	*
	13	* So digest(a,b,c,d) will be the same of digest(b,a,c,d) */
	14	void xorDigest(unsigned char digest, void ptr, size_t len) {
	15	SHA1_CTX ctx;
	16	unsigned char hash[20], *s = ptr;
	17	int j;
	18
	19	SHA1Init(&ctx);
	20	SHA1Update(&ctx,s,len);
	21	SHA1Final(hash,&ctx);
	22
	23	for (j = 0; j < 20; j++)
	24	digest[j] ^= hash[j];
	25	}
	26
	27	void xorObjectDigest(unsigned char digest, robj o) {
	28	o = getDecodedObject(o);
	29	xorDigest(digest,o->ptr,sdslen(o->ptr));
	30	decrRefCount(o);
	31	}
	32
	33	/* This function instead of just computing the SHA1 and xoring it
	34	* against diget, also perform the digest of "digest" itself and
	35	* replace the old value with the new one.
	36	*
	37	* So the final digest will be:
	38	*
	39	* digest = SHA1(digest xor SHA1(data))
	40	*
	41	* This function is used every time we want to preserve the order so
	42	* that digest(a,b,c,d) will be different than digest(b,c,d,a)
	43	*
	44	* Also note that mixdigest("foo") followed by mixdigest("bar")
	45	* will lead to a different digest compared to "fo", "obar".
	46	*/
	47	void mixDigest(unsigned char digest, void ptr, size_t len) {
	48	SHA1_CTX ctx;
	49	char *s = ptr;
	50
	51	xorDigest(digest,s,len);
	52	SHA1Init(&ctx);
	53	SHA1Update(&ctx,digest,20);
	54	SHA1Final(digest,&ctx);
	55	}
	56
	57	void mixObjectDigest(unsigned char digest, robj o) {
	58	o = getDecodedObject(o);
	59	mixDigest(digest,o->ptr,sdslen(o->ptr));
	60	decrRefCount(o);
	61	}
	62
	63	/* Compute the dataset digest. Since keys, sets elements, hashes elements
	64	* are not ordered, we use a trick: every aggregate digest is the xor
	65	* of the digests of their elements. This way the order will not change
	66	* the result. For list instead we use a feedback entering the output digest
	67	* as input in order to ensure that a different ordered list will result in
	68	* a different digest. */
	69	void computeDatasetDigest(unsigned char *final) {
70	unsigned char digest[20];
71	char buf[128];
72	dictIterator *di = NULL;
73	dictEntry *de;
74	int j;
75	uint32_t aux;
76
77	memset(final,0,20); /* Start with a clean result */
78
79	for (j = 0; j < server.dbnum; j++) {
80	redisDb *db = server.db+j;
81
82	if (dictSize(db->dict) == 0) continue;
83	di = dictGetIterator(db->dict);
84
85	/* hash the DB id, so the same dataset moved in a different
86	* DB will lead to a different digest */
87	aux = htonl(j);
88	mixDigest(final,&aux,sizeof(aux));
89
90	/* Iterate this DB writing every entry */
91	while((de = dictNext(di)) != NULL) {
92	sds key;
93	robj keyobj, o;
94	time_t expiretime;
95
96	memset(digest,0,20); /* This key-val digest */
97	key = dictGetEntryKey(de);
98	keyobj = createStringObject(key,sdslen(key));
99
100	mixDigest(digest,key,sdslen(key));
101
102	/* Make sure the key is loaded if VM is active */
103	o = lookupKeyRead(db,keyobj);
104
105	aux = htonl(o->type);
106	mixDigest(digest,&aux,sizeof(aux));
107	expiretime = getExpire(db,keyobj);
108
109	/* Save the key and associated value */
110	if (o->type == REDIS_STRING) {
111	mixObjectDigest(digest,o);
112	} else if (o->type == REDIS_LIST) {
113	listTypeIterator *li = listTypeInitIterator(o,0,REDIS_TAIL);
114	listTypeEntry entry;
115	while(listTypeNext(li,&entry)) {
116	robj *eleobj = listTypeGet(&entry);
117	mixObjectDigest(digest,eleobj);
118	decrRefCount(eleobj);
119	}
120	listTypeReleaseIterator(li);
121	} else if (o->type == REDIS_SET) {
cb72d0f1	122	setTypeIterator *si = setTypeInitIterator(o);
2767f1c0	123	robj *ele;
1b508da7	124	while((ele = setTypeNextObject(si)) != NULL) {
2767f1c0 PN	125	xorObjectDigest(digest,ele);
2767f1c0 PN	126	decrRefCount(ele);
e2641e09	127	}
2767f1c0	128	setTypeReleaseIterator(si);
e2641e09	129	} else if (o->type == REDIS_ZSET) {
	130	zset *zs = o->ptr;
	131	dictIterator *di = dictGetIterator(zs->dict);
	132	dictEntry *de;
	133
	134	while((de = dictNext(di)) != NULL) {
	135	robj *eleobj = dictGetEntryKey(de);
	136	double *score = dictGetEntryVal(de);
	137	unsigned char eledigest[20];
	138
	139	snprintf(buf,sizeof(buf),"%.17g",*score);
	140	memset(eledigest,0,20);
	141	mixObjectDigest(eledigest,eleobj);
	142	mixDigest(eledigest,buf,strlen(buf));
	143	xorDigest(digest,eledigest,20);
	144	}
	145	dictReleaseIterator(di);
	146	} else if (o->type == REDIS_HASH) {
	147	hashTypeIterator *hi;
	148	robj *obj;
	149
	150	hi = hashTypeInitIterator(o);
	151	while (hashTypeNext(hi) != REDIS_ERR) {
	152	unsigned char eledigest[20];
	153
	154	memset(eledigest,0,20);
8c304be3	155	obj = hashTypeCurrentObject(hi,REDIS_HASH_KEY);
e2641e09	156	mixObjectDigest(eledigest,obj);
e2641e09	157	decrRefCount(obj);
8c304be3	158	obj = hashTypeCurrentObject(hi,REDIS_HASH_VALUE);
e2641e09	159	mixObjectDigest(eledigest,obj);
	160	decrRefCount(obj);
	161	xorDigest(digest,eledigest,20);
	162	}
	163	hashTypeReleaseIterator(hi);
	164	} else {
	165	redisPanic("Unknown object type");
	166	}
	167	/* If the key has an expire, add it to the mix */
	168	if (expiretime != -1) xorDigest(digest,"!!expire!!",10);
	169	/* We can finally xor the key-val digest to the final digest */
	170	xorDigest(final,digest,20);
	171	decrRefCount(keyobj);
	172	}
	173	dictReleaseIterator(di);
	174	}
	175	}
	176
	177	void debugCommand(redisClient *c) {
	178	if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
	179	((char)-1) = 'x';
	180	} else if (!strcasecmp(c->argv[1]->ptr,"reload")) {
	181	if (rdbSave(server.dbfilename) != REDIS_OK) {
	182	addReply(c,shared.err);
	183	return;
	184	}
	185	emptyDb();
	186	if (rdbLoad(server.dbfilename) != REDIS_OK) {
	187	addReply(c,shared.err);
	188	return;
	189	}
	190	redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD");
	191	addReply(c,shared.ok);
	192	} else if (!strcasecmp(c->argv[1]->ptr,"loadaof")) {
	193	emptyDb();
	194	if (loadAppendOnlyFile(server.appendfilename) != REDIS_OK) {
	195	addReply(c,shared.err);
	196	return;
	197	}
	198	redisLog(REDIS_WARNING,"Append Only File loaded by DEBUG LOADAOF");
	199	addReply(c,shared.ok);
	200	} else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) {
	201	dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
	202	robj *val;
5ef64098	203	char *strenc;
e2641e09	204
	205	if (!de) {
	206	addReply(c,shared.nokeyerr);
	207	return;
	208	}
	209	val = dictGetEntryVal(de);
5ef64098	210	strenc = strEncoding(val->encoding);
3be00d7e	211
5ef64098	212	addReplyStatusFormat(c,
	213	"Value at:%p refcount:%d "
	214	"encoding:%s serializedlength:%lld "
3be00d7e	215	"lru:%d lru_seconds_idle:%lu",
5ef64098	216	(void*)val, val->refcount,
5ef64098	217	strenc, (long long) rdbSavedObjectLen(val),
3be00d7e	218	val->lru, estimateObjectIdleTime(val));
e2641e09	219	} else if (!strcasecmp(c->argv[1]->ptr,"populate") && c->argc == 3) {
	220	long keys, j;
	221	robj key, val;
	222	char buf[128];
	223
	224	if (getLongFromObjectOrReply(c, c->argv[2], &keys, NULL) != REDIS_OK)
	225	return;
	226	for (j = 0; j < keys; j++) {
	227	snprintf(buf,sizeof(buf),"key:%lu",j);
	228	key = createStringObject(buf,strlen(buf));
	229	if (lookupKeyRead(c->db,key) != NULL) {
	230	decrRefCount(key);
	231	continue;
	232	}
	233	snprintf(buf,sizeof(buf),"value:%lu",j);
	234	val = createStringObject(buf,strlen(buf));
	235	dbAdd(c->db,key,val);
	236	decrRefCount(key);
	237	}
	238	addReply(c,shared.ok);
	239	} else if (!strcasecmp(c->argv[1]->ptr,"digest") && c->argc == 2) {
	240	unsigned char digest[20];
3ab20376	241	sds d = sdsempty();
e2641e09	242	int j;
	243
	244	computeDatasetDigest(digest);
	245	for (j = 0; j < 20; j++)
	246	d = sdscatprintf(d, "%02x",digest[j]);
3ab20376 PN	247	addReplyStatus(c,d);
3ab20376 PN	248	sdsfree(d);
e2641e09	249	} else {
3ab20376 PN	250	addReplyError(c,
3ab20376 PN	251	"Syntax error, try DEBUG [SEGFAULT\|OBJECT <key>\|SWAPIN <key>\|SWAPOUT <key>\|RELOAD]");
e2641e09	252	}
	253	}
	254
	255	void _redisAssert(char estr, char file, int line) {
	256	redisLog(REDIS_WARNING,"=== ASSERTION FAILED ===");
	257	redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true",file,line,estr);
	258	#ifdef HAVE_BACKTRACE
	259	redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
	260	((char)-1) = 'x';
	261	#endif
	262	}
	263
	264	void _redisPanic(char msg, char file, int line) {
120b9ba8	265	redisLog(REDIS_WARNING,"------------------------------------------------");
e2641e09	266	redisLog(REDIS_WARNING,"!!! Software Failure. Press left mouse button to continue");
	267	redisLog(REDIS_WARNING,"Guru Meditation: %s #%s:%d",msg,file,line);
	268	#ifdef HAVE_BACKTRACE
	269	redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
120b9ba8	270	redisLog(REDIS_WARNING,"------------------------------------------------");
e2641e09	271	((char)-1) = 'x';
	272	#endif
	273	}