[redis.git] / src / debug.c

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

/* ================================= 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) {
                dict *set = o->ptr;
                dictIterator *di = dictGetIterator(set);
                dictEntry *de;

                while((de = dictNext(di)) != NULL) {
                    robj *eleobj = dictGetEntryKey(de);

                    xorObjectDigest(digest,eleobj);
                }
                dictReleaseIterator(di);
            } 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 = hashTypeCurrent(hi,REDIS_HASH_KEY);
                    mixObjectDigest(eledigest,obj);
                    decrRefCount(obj);
                    obj = hashTypeCurrent(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;

        if (!de) {
            addReply(c,shared.nokeyerr);
            return;
        }
        val = dictGetEntryVal(de);
        if (!server.vm_enabled || (val->storage == REDIS_VM_MEMORY ||
                                   val->storage == REDIS_VM_SWAPPING)) {
            char *strenc;

            strenc = strEncoding(val->encoding);
            addReplySds(c,sdscatprintf(sdsempty(),
                "+Value at:%p refcount:%d "
                "encoding:%s serializedlength:%lld\r\n",
                (void*)val, val->refcount,
                strenc, (long long) rdbSavedObjectLen(val,NULL)));
        } else {
            vmpointer *vp = (vmpointer*) val;
            addReplySds(c,sdscatprintf(sdsempty(),
                "+Value swapped at: page %llu "
                "using %llu pages\r\n",
                (unsigned long long) vp->page,
                (unsigned long long) vp->usedpages));
        }
    } else if (!strcasecmp(c->argv[1]->ptr,"swapin") && c->argc == 3) {
        lookupKeyRead(c->db,c->argv[2]);
        addReply(c,shared.ok);
    } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) {
        dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
        robj *val;
        vmpointer *vp;

        if (!server.vm_enabled) {
            addReplySds(c,sdsnew("-ERR Virtual Memory is disabled\r\n"));
            return;
        }
        if (!de) {
            addReply(c,shared.nokeyerr);
            return;
        }
        val = dictGetEntryVal(de);
        /* Swap it */
        if (val->storage != REDIS_VM_MEMORY) {
            addReplySds(c,sdsnew("-ERR This key is not in memory\r\n"));
        } else if (val->refcount != 1) {
            addReplySds(c,sdsnew("-ERR Object is shared\r\n"));
        } else if ((vp = vmSwapObjectBlocking(val)) != NULL) {
            dictGetEntryVal(de) = vp;
            addReply(c,shared.ok);
        } else {
            addReply(c,shared.err);
        }
    } 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 = sdsnew("+");
        int j;

        computeDatasetDigest(digest);
        for (j = 0; j < 20; j++)
            d = sdscatprintf(d, "%02x",digest[j]);

        d = sdscatlen(d,"\r\n",2);
        addReplySds(c,d);
    } else {
        addReplySds(c,sdsnew(
            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|SWAPIN <key>|SWAPOUT <key>|RELOAD]\r\n"));
    }
}

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,"!!! 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)");
    *((char*)-1) = 'x';
#endif
}
Commit	Line	Data
e2641e09	1	#include "redis.h"
	2	#include "sha1.h" /* SHA1 is used for DEBUG DIGEST */
	3
	4	/* ================================= Debugging ============================== */
	5
	6	/* Compute the sha1 of string at 's' with 'len' bytes long.
	7	* The SHA1 is then xored againt the string pointed by digest.
	8	* Since xor is commutative, this operation is used in order to
	9	* "add" digests relative to unordered elements.
	10	*
	11	* So digest(a,b,c,d) will be the same of digest(b,a,c,d) */
	12	void xorDigest(unsigned char digest, void ptr, size_t len) {
	13	SHA1_CTX ctx;
	14	unsigned char hash[20], *s = ptr;
	15	int j;
	16
	17	SHA1Init(&ctx);
	18	SHA1Update(&ctx,s,len);
	19	SHA1Final(hash,&ctx);
	20
	21	for (j = 0; j < 20; j++)
	22	digest[j] ^= hash[j];
	23	}
	24
	25	void xorObjectDigest(unsigned char digest, robj o) {
	26	o = getDecodedObject(o);
	27	xorDigest(digest,o->ptr,sdslen(o->ptr));
	28	decrRefCount(o);
	29	}
	30
	31	/* This function instead of just computing the SHA1 and xoring it
	32	* against diget, also perform the digest of "digest" itself and
	33	* replace the old value with the new one.
	34	*
	35	* So the final digest will be:
	36	*
	37	* digest = SHA1(digest xor SHA1(data))
	38	*
	39	* This function is used every time we want to preserve the order so
	40	* that digest(a,b,c,d) will be different than digest(b,c,d,a)
	41	*
	42	* Also note that mixdigest("foo") followed by mixdigest("bar")
	43	* will lead to a different digest compared to "fo", "obar".
	44	*/
	45	void mixDigest(unsigned char digest, void ptr, size_t len) {
	46	SHA1_CTX ctx;
	47	char *s = ptr;
	48
	49	xorDigest(digest,s,len);
	50	SHA1Init(&ctx);
	51	SHA1Update(&ctx,digest,20);
	52	SHA1Final(digest,&ctx);
	53	}
	54
	55	void mixObjectDigest(unsigned char digest, robj o) {
	56	o = getDecodedObject(o);
	57	mixDigest(digest,o->ptr,sdslen(o->ptr));
	58	decrRefCount(o);
	59	}
	60
	61	/* Compute the dataset digest. Since keys, sets elements, hashes elements
	62	* are not ordered, we use a trick: every aggregate digest is the xor
	63	* of the digests of their elements. This way the order will not change
	64	* the result. For list instead we use a feedback entering the output digest
65	* as input in order to ensure that a different ordered list will result in
66	* a different digest. */
67	void computeDatasetDigest(unsigned char *final) {
68	unsigned char digest[20];
69	char buf[128];
70	dictIterator *di = NULL;
71	dictEntry *de;
72	int j;
73	uint32_t aux;
74
75	memset(final,0,20); /* Start with a clean result */
76
77	for (j = 0; j < server.dbnum; j++) {
78	redisDb *db = server.db+j;
79
80	if (dictSize(db->dict) == 0) continue;
81	di = dictGetIterator(db->dict);
82
83	/* hash the DB id, so the same dataset moved in a different
84	* DB will lead to a different digest */
85	aux = htonl(j);
86	mixDigest(final,&aux,sizeof(aux));
87
88	/* Iterate this DB writing every entry */
89	while((de = dictNext(di)) != NULL) {
90	sds key;
91	robj keyobj, o;
92	time_t expiretime;
93
94	memset(digest,0,20); /* This key-val digest */
95	key = dictGetEntryKey(de);
96	keyobj = createStringObject(key,sdslen(key));
97
98	mixDigest(digest,key,sdslen(key));
99
100	/* Make sure the key is loaded if VM is active */
101	o = lookupKeyRead(db,keyobj);
102
103	aux = htonl(o->type);
104	mixDigest(digest,&aux,sizeof(aux));
105	expiretime = getExpire(db,keyobj);
106
107	/* Save the key and associated value */
108	if (o->type == REDIS_STRING) {
109	mixObjectDigest(digest,o);
110	} else if (o->type == REDIS_LIST) {
111	listTypeIterator *li = listTypeInitIterator(o,0,REDIS_TAIL);
112	listTypeEntry entry;
113	while(listTypeNext(li,&entry)) {
114	robj *eleobj = listTypeGet(&entry);
115	mixObjectDigest(digest,eleobj);
116	decrRefCount(eleobj);
117	}
118	listTypeReleaseIterator(li);
119	} else if (o->type == REDIS_SET) {
120	dict *set = o->ptr;
121	dictIterator *di = dictGetIterator(set);
122	dictEntry *de;
123
124	while((de = dictNext(di)) != NULL) {
125	robj *eleobj = dictGetEntryKey(de);
126
127	xorObjectDigest(digest,eleobj);
128	}
129	dictReleaseIterator(di);
130	} else if (o->type == REDIS_ZSET) {
131	zset *zs = o->ptr;
132	dictIterator *di = dictGetIterator(zs->dict);
133	dictEntry *de;
134
135	while((de = dictNext(di)) != NULL) {
136	robj *eleobj = dictGetEntryKey(de);
137	double *score = dictGetEntryVal(de);
138	unsigned char eledigest[20];
139
140	snprintf(buf,sizeof(buf),"%.17g",*score);
141	memset(eledigest,0,20);
142	mixObjectDigest(eledigest,eleobj);
143	mixDigest(eledigest,buf,strlen(buf));
144	xorDigest(digest,eledigest,20);
145	}
146	dictReleaseIterator(di);
147	} else if (o->type == REDIS_HASH) {
148	hashTypeIterator *hi;
149	robj *obj;
150
151	hi = hashTypeInitIterator(o);
152	while (hashTypeNext(hi) != REDIS_ERR) {
153	unsigned char eledigest[20];
154
155	memset(eledigest,0,20);
156	obj = hashTypeCurrent(hi,REDIS_HASH_KEY);
157	mixObjectDigest(eledigest,obj);
158	decrRefCount(obj);
159	obj = hashTypeCurrent(hi,REDIS_HASH_VALUE);
160	mixObjectDigest(eledigest,obj);
161	decrRefCount(obj);
162	xorDigest(digest,eledigest,20);
163	}
164	hashTypeReleaseIterator(hi);
165	} else {
166	redisPanic("Unknown object type");
167	}
168	/* If the key has an expire, add it to the mix */
169	if (expiretime != -1) xorDigest(digest,"!!expire!!",10);
170	/* We can finally xor the key-val digest to the final digest */
171	xorDigest(final,digest,20);
172	decrRefCount(keyobj);
173	}
174	dictReleaseIterator(di);
175	}
176	}
177
178	void debugCommand(redisClient *c) {
179	if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
180	((char)-1) = 'x';
181	} else if (!strcasecmp(c->argv[1]->ptr,"reload")) {
182	if (rdbSave(server.dbfilename) != REDIS_OK) {
183	addReply(c,shared.err);
184	return;
185	}
186	emptyDb();
187	if (rdbLoad(server.dbfilename) != REDIS_OK) {
188	addReply(c,shared.err);
189	return;
190	}
191	redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD");
192	addReply(c,shared.ok);
193	} else if (!strcasecmp(c->argv[1]->ptr,"loadaof")) {
194	emptyDb();
195	if (loadAppendOnlyFile(server.appendfilename) != REDIS_OK) {
196	addReply(c,shared.err);
197	return;
198	}
199	redisLog(REDIS_WARNING,"Append Only File loaded by DEBUG LOADAOF");
200	addReply(c,shared.ok);
201	} else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) {
202	dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
203	robj *val;
204
205	if (!de) {
206	addReply(c,shared.nokeyerr);
207	return;
208	}
209	val = dictGetEntryVal(de);
210	if (!server.vm_enabled \|\| (val->storage == REDIS_VM_MEMORY \|\|
211	val->storage == REDIS_VM_SWAPPING)) {
212	char *strenc;
213
214	strenc = strEncoding(val->encoding);
215	addReplySds(c,sdscatprintf(sdsempty(),
216	"+Value at:%p refcount:%d "
217	"encoding:%s serializedlength:%lld\r\n",
218	(void*)val, val->refcount,
219	strenc, (long long) rdbSavedObjectLen(val,NULL)));
220	} else {
221	vmpointer vp = (vmpointer) val;
222	addReplySds(c,sdscatprintf(sdsempty(),
223	"+Value swapped at: page %llu "
224	"using %llu pages\r\n",
225	(unsigned long long) vp->page,
226	(unsigned long long) vp->usedpages));
227	}
228	} else if (!strcasecmp(c->argv[1]->ptr,"swapin") && c->argc == 3) {
229	lookupKeyRead(c->db,c->argv[2]);
230	addReply(c,shared.ok);
231	} else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) {
232	dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr);
233	robj *val;
234	vmpointer *vp;
235
236	if (!server.vm_enabled) {
237	addReplySds(c,sdsnew("-ERR Virtual Memory is disabled\r\n"));
238	return;
239	}
240	if (!de) {
241	addReply(c,shared.nokeyerr);
242	return;
243	}
244	val = dictGetEntryVal(de);
245	/* Swap it */
246	if (val->storage != REDIS_VM_MEMORY) {
247	addReplySds(c,sdsnew("-ERR This key is not in memory\r\n"));
248	} else if (val->refcount != 1) {
249	addReplySds(c,sdsnew("-ERR Object is shared\r\n"));
250	} else if ((vp = vmSwapObjectBlocking(val)) != NULL) {
251	dictGetEntryVal(de) = vp;
252	addReply(c,shared.ok);
253	} else {
254	addReply(c,shared.err);
255	}
256	} else if (!strcasecmp(c->argv[1]->ptr,"populate") && c->argc == 3) {
257	long keys, j;
258	robj key, val;
259	char buf[128];
260
261	if (getLongFromObjectOrReply(c, c->argv[2], &keys, NULL) != REDIS_OK)
262	return;
263	for (j = 0; j < keys; j++) {
264	snprintf(buf,sizeof(buf),"key:%lu",j);
265	key = createStringObject(buf,strlen(buf));
266	if (lookupKeyRead(c->db,key) != NULL) {
267	decrRefCount(key);
268	continue;
269	}
270	snprintf(buf,sizeof(buf),"value:%lu",j);
271	val = createStringObject(buf,strlen(buf));
272	dbAdd(c->db,key,val);
273	decrRefCount(key);
274	}
275	addReply(c,shared.ok);
276	} else if (!strcasecmp(c->argv[1]->ptr,"digest") && c->argc == 2) {
277	unsigned char digest[20];
278	sds d = sdsnew("+");
279	int j;
280
281	computeDatasetDigest(digest);
282	for (j = 0; j < 20; j++)
283	d = sdscatprintf(d, "%02x",digest[j]);
284
285	d = sdscatlen(d,"\r\n",2);
286	addReplySds(c,d);
287	} else {
288	addReplySds(c,sdsnew(
289	"-ERR Syntax error, try DEBUG [SEGFAULT\|OBJECT <key>\|SWAPIN <key>\|SWAPOUT <key>\|RELOAD]\r\n"));
290	}
291	}
292
293	void _redisAssert(char estr, char file, int line) {
294	redisLog(REDIS_WARNING,"=== ASSERTION FAILED ===");
295	redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true",file,line,estr);
296	#ifdef HAVE_BACKTRACE
297	redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
298	((char)-1) = 'x';
299	#endif
300	}
301
302	void _redisPanic(char msg, char file, int line) {
303	redisLog(REDIS_WARNING,"!!! Software Failure. Press left mouse button to continue");
304	redisLog(REDIS_WARNING,"Guru Meditation: %s #%s:%d",msg,file,line);
305	#ifdef HAVE_BACKTRACE
306	redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
307	((char)-1) = 'x';
308	#endif
309	}