#include <sys/resource.h>
#include <sys/uio.h>
#include <limits.h>
+#include <float.h>
#include <math.h>
#include <pthread.h>
#include "zmalloc.h" /* total memory usage aware version of malloc/free */
#include "lzf.h" /* LZF compression library */
#include "pqsort.h" /* Partial qsort for SORT+LIMIT */
-#include "zipmap.h"
+#include "zipmap.h" /* Compact dictionary-alike data structure */
+#include "sha1.h" /* SHA1 is used for DEBUG DIGEST */
/* Error codes */
#define REDIS_OK 0
} pubsubPattern;
typedef void redisCommandProc(redisClient *c);
+typedef void redisVmPreloadProc(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
struct redisCommand {
char *name;
redisCommandProc *proc;
/* Use a function to determine which keys need to be loaded
* in the background prior to executing this command. Takes precedence
* over vm_firstkey and others, ignored when NULL */
- redisCommandProc *vm_preload_proc;
+ redisVmPreloadProc *vm_preload_proc;
/* What keys should be loaded in background when calling this command? */
int vm_firstkey; /* The first argument that's a key (0 = no keys) */
int vm_lastkey; /* THe last argument that's a key */
static void waitEmptyIOJobsQueue(void);
static void vmReopenSwapFile(void);
static int vmFreePage(off_t page);
-static void zunionInterBlockClientOnSwappedKeys(redisClient *c);
-static int blockClientOnSwappedKeys(struct redisCommand *cmd, redisClient *c);
+static void zunionInterBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+static void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv);
+static int blockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd);
static int dontWaitForSwappedKey(redisClient *c, robj *key);
static void handleClientsBlockedOnSwappedKey(redisDb *db, robj *key);
static void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mask);
static void hdelCommand(redisClient *c);
static void hlenCommand(redisClient *c);
static void zremrangebyrankCommand(redisClient *c);
-static void zunionCommand(redisClient *c);
-static void zinterCommand(redisClient *c);
+static void zunionstoreCommand(redisClient *c);
+static void zinterstoreCommand(redisClient *c);
static void hkeysCommand(redisClient *c);
static void hvalsCommand(redisClient *c);
static void hgetallCommand(redisClient *c);
{"zrem",zremCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
{"zremrangebyscore",zremrangebyscoreCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
{"zremrangebyrank",zremrangebyrankCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
- {"zunion",zunionCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
- {"zinter",zinterCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
+ {"zunionstore",zunionstoreCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
+ {"zinterstore",zinterstoreCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
{"zrange",zrangeCommand,-4,REDIS_CMD_INLINE,NULL,1,1,1},
{"zrangebyscore",zrangebyscoreCommand,-4,REDIS_CMD_INLINE,NULL,1,1,1},
{"zcount",zcountCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
{"lastsave",lastsaveCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
{"type",typeCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
{"multi",multiCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
- {"exec",execCommand,1,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,0,0,0},
+ {"exec",execCommand,1,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,execBlockClientOnSwappedKeys,0,0,0},
{"discard",discardCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
{"sync",syncCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
{"flushdb",flushdbCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
return val*mul;
}
+/* Convert a long long into a string. Returns the number of
+ * characters needed to represent the number, that can be shorter if passed
+ * buffer length is not enough to store the whole number. */
+static int ll2string(char *s, size_t len, long long value) {
+ char buf[32], *p;
+ unsigned long long v;
+ size_t l;
+
+ if (len == 0) return 0;
+ v = (value < 0) ? -value : value;
+ p = buf+31; /* point to the last character */
+ do {
+ *p-- = '0'+(v%10);
+ v /= 10;
+ } while(v);
+ if (value < 0) *p-- = '-';
+ p++;
+ l = 32-(p-buf);
+ if (l+1 > len) l = len-1; /* Make sure it fits, including the nul term */
+ memcpy(s,p,l);
+ s[l] = '\0';
+ return l;
+}
+
static void redisLog(int level, const char *fmt, ...) {
va_list ap;
FILE *fp;
char buf[32];
int len;
- len = snprintf(buf,32,"%ld",(long)o->ptr);
+ len = ll2string(buf,32,(long)o->ptr);
return dictGenHashFunction((unsigned char*)buf, len);
} else {
unsigned int hash;
if ((server.appendonly = yesnotoi(argv[1])) == -1) {
err = "argument must be 'yes' or 'no'"; goto loaderr;
}
+ } else if (!strcasecmp(argv[0],"appendfilename") && argc == 2) {
+ zfree(server.appendfilename);
+ server.appendfilename = zstrdup(argv[1]);
} else if (!strcasecmp(argv[0],"appendfsync") && argc == 2) {
if (!strcasecmp(argv[1],"no")) {
server.appendfsync = APPENDFSYNC_NO;
addReply(c,shared.queued);
} else {
if (server.vm_enabled && server.vm_max_threads > 0 &&
- blockClientOnSwappedKeys(cmd,c)) return 1;
+ blockClientOnSwappedKeys(c,cmd)) return 1;
call(c,cmd);
}
o->encoding = REDIS_ENCODING_INT;
o->ptr = (void*)((long)value);
} else {
- char buf[32], *p;
- char *c = "0123456789";
- unsigned long v;
-
- v = (value < 0) ? -value : value;
- p = buf+31; /* point to the last character */
- while(v) {
- *p-- = c[v%10];
- v /= 10;
- }
- if (value < 0) *p-- = '-';
- p++;
- o = createObject(REDIS_STRING,sdsnewlen(p,32-(p-buf+1)));
+ o = createObject(REDIS_STRING,sdsfromlonglong(value));
}
}
return o;
value = strtol(s, &endptr, 10);
if (endptr[0] != '\0') return REDIS_ERR;
- slen = snprintf(buf,32,"%ld",value);
+ slen = ll2string(buf,32,value);
/* If the number converted back into a string is not identical
* then it's not possible to encode the string as integer */
if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
char buf[32];
- snprintf(buf,32,"%ld",(long)o->ptr);
+ ll2string(buf,32,(long)o->ptr);
dec = createStringObject(buf,strlen(buf));
return dec;
} else {
/* Compare two string objects via strcmp() or alike.
* Note that the objects may be integer-encoded. In such a case we
- * use snprintf() to get a string representation of the numbers on the stack
+ * 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,
if (a == b) return 0;
if (a->encoding != REDIS_ENCODING_RAW) {
- snprintf(bufa,sizeof(bufa),"%ld",(long) a->ptr);
+ ll2string(bufa,sizeof(bufa),(long) a->ptr);
astr = bufa;
bothsds = 0;
} else {
astr = a->ptr;
}
if (b->encoding != REDIS_ENCODING_RAW) {
- snprintf(bufb,sizeof(bufb),"%ld",(long) b->ptr);
+ ll2string(bufb,sizeof(bufb),(long) b->ptr);
bstr = bufb;
bothsds = 0;
} else {
} else {
char buf[32];
- return snprintf(buf,32,"%ld",(long)o->ptr);
+ return ll2string(buf,32,(long)o->ptr);
}
}
return 0;
}
-/* String objects in the form "2391" "-100" without any space and with a
- * range of values that can fit in an 8, 16 or 32 bit signed value can be
- * encoded as integers to save space */
-static int rdbTryIntegerEncoding(char *s, size_t len, unsigned char *enc) {
- long long value;
- char *endptr, buf[32];
-
- /* Check if it's possible to encode this value as a number */
- value = strtoll(s, &endptr, 10);
- if (endptr[0] != '\0') return 0;
- snprintf(buf,32,"%lld",value);
-
- /* If the number converted back into a string is not identical
- * then it's not possible to encode the string as integer */
- if (strlen(buf) != len || memcmp(buf,s,len)) return 0;
-
+/* Encode 'value' as an integer if possible (if integer will fit the
+ * supported range). If the function sucessful encoded the integer
+ * then the (up to 5 bytes) encoded representation is written in the
+ * string pointed by 'enc' and the length is returned. Otherwise
+ * 0 is returned. */
+static int rdbEncodeInteger(long long value, unsigned char *enc) {
/* Finally check if it fits in our ranges */
if (value >= -(1<<7) && value <= (1<<7)-1) {
enc[0] = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_INT8;
}
}
+/* String objects in the form "2391" "-100" without any space and with a
+ * range of values that can fit in an 8, 16 or 32 bit signed value can be
+ * encoded as integers to save space */
+static int rdbTryIntegerEncoding(char *s, size_t len, unsigned char *enc) {
+ long long value;
+ char *endptr, buf[32];
+
+ /* Check if it's possible to encode this value as a number */
+ value = strtoll(s, &endptr, 10);
+ if (endptr[0] != '\0') return 0;
+ ll2string(buf,32,value);
+
+ /* If the number converted back into a string is not identical
+ * then it's not possible to encode the string as integer */
+ if (strlen(buf) != len || memcmp(buf,s,len)) return 0;
+
+ return rdbEncodeInteger(value,enc);
+}
+
static int rdbSaveLzfStringObject(FILE *fp, unsigned char *s, size_t len) {
size_t comprlen, outlen;
unsigned char byte;
static int rdbSaveStringObject(FILE *fp, robj *obj) {
int retval;
+ /* Avoid to decode the object, then encode it again, if the
+ * object is alrady integer encoded. */
+ if (obj->encoding == REDIS_ENCODING_INT) {
+ long val = (long) obj->ptr;
+ unsigned char buf[5];
+ int enclen;
+
+ if ((enclen = rdbEncodeInteger(val,buf)) > 0) {
+ if (fwrite(buf,enclen,1,fp) == 0) return -1;
+ return 0;
+ }
+ /* otherwise... fall throught and continue with the usual
+ * code path. */
+ }
+
/* Avoid incr/decr ref count business when possible.
* This plays well with copy-on-write given that we are probably
* in a child process (BGSAVE). Also this makes sure key objects
len = 1;
buf[0] = (val < 0) ? 255 : 254;
} else {
- snprintf((char*)buf+1,sizeof(buf)-1,"%.17g",val);
+#if (DBL_MANT_DIG >= 52) && (LLONG_MAX == 0x7fffffffffffffffLL)
+ /* Check if the float is in a safe range to be casted into a
+ * long long. We are assuming that long long is 64 bit here.
+ * Also we are assuming that there are no implementations around where
+ * double has precision < 52 bit.
+ *
+ * Under this assumptions we test if a double is inside an interval
+ * where casting to long long is safe. Then using two castings we
+ * make sure the decimal part is zero. If all this is true we use
+ * integer printing function that is much faster. */
+ double min = -4503599627370495; /* (2^52)-1 */
+ double max = 4503599627370496; /* -(2^52) */
+ if (val > min && val < max && val == ((double)((long long)val)))
+ ll2string((char*)buf+1,sizeof(buf),(long long)val);
+ else
+#endif
+ snprintf((char*)buf+1,sizeof(buf)-1,"%.17g",val);
buf[0] = strlen((char*)buf+1);
len = buf[0]+1;
}
}
}
-static robj *rdbLoadIntegerObject(FILE *fp, int enctype) {
+/* Load an integer-encoded object from file 'fp', with the specified
+ * encoding type 'enctype'. If encode is true the function may return
+ * an integer-encoded object as reply, otherwise the returned object
+ * will always be encoded as a raw string. */
+static robj *rdbLoadIntegerObject(FILE *fp, int enctype, int encode) {
unsigned char enc[4];
long long val;
val = 0; /* anti-warning */
redisPanic("Unknown RDB integer encoding type");
}
- return createStringObjectFromLongLong(val);
+ if (encode)
+ return createStringObjectFromLongLong(val);
+ else
+ return createObject(REDIS_STRING,sdsfromlonglong(val));
}
static robj *rdbLoadLzfStringObject(FILE*fp) {
return NULL;
}
-static robj *rdbLoadStringObject(FILE*fp) {
+static robj *rdbGenericLoadStringObject(FILE*fp, int encode) {
int isencoded;
uint32_t len;
sds val;
case REDIS_RDB_ENC_INT8:
case REDIS_RDB_ENC_INT16:
case REDIS_RDB_ENC_INT32:
- return rdbLoadIntegerObject(fp,len);
+ return rdbLoadIntegerObject(fp,len,encode);
case REDIS_RDB_ENC_LZF:
return rdbLoadLzfStringObject(fp);
default:
return createObject(REDIS_STRING,val);
}
+static robj *rdbLoadStringObject(FILE *fp) {
+ return rdbGenericLoadStringObject(fp,0);
+}
+
+static robj *rdbLoadEncodedStringObject(FILE *fp) {
+ return rdbGenericLoadStringObject(fp,1);
+}
+
/* For information about double serialization check rdbSaveDoubleValue() */
static int rdbLoadDoubleValue(FILE *fp, double *val) {
char buf[128];
redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",type,ftell(fp));
if (type == REDIS_STRING) {
/* Read string value */
- if ((o = rdbLoadStringObject(fp)) == NULL) return NULL;
+ if ((o = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
o = tryObjectEncoding(o);
} else if (type == REDIS_LIST || type == REDIS_SET) {
/* Read list/set value */
while(listlen--) {
robj *ele;
- if ((ele = rdbLoadStringObject(fp)) == NULL) return NULL;
+ if ((ele = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
ele = tryObjectEncoding(ele);
if (type == REDIS_LIST) {
listAddNodeTail((list*)o->ptr,ele);
robj *ele;
double *score = zmalloc(sizeof(double));
- if ((ele = rdbLoadStringObject(fp)) == NULL) return NULL;
+ if ((ele = rdbLoadEncodedStringObject(fp)) == NULL) return NULL;
ele = tryObjectEncoding(ele);
if (rdbLoadDoubleValue(fp,score) == -1) return NULL;
dictAdd(zs->dict,ele,score);
robj *o;
o = lookupKeyWrite(c->db,c->argv[1]);
-
- if (getLongLongFromObjectOrReply(c, o, &value, NULL) != REDIS_OK) return;
+ if (o != NULL && checkType(c,o,REDIS_STRING)) return;
+ if (getLongLongFromObjectOrReply(c,o,&value,NULL) != REDIS_OK) return;
value += incr;
o = createObject(REDIS_STRING,sdscatprintf(sdsempty(),"%lld",value));
}
static void existsCommand(redisClient *c) {
- addReply(c,lookupKeyRead(c->db,c->argv[1]) ? shared.cone : shared.czero);
+ expireIfNeeded(c->db,c->argv[1]);
+ if (dictFind(c->db->dict,c->argv[1])) {
+ addReply(c, shared.cone);
+ } else {
+ addReply(c, shared.czero);
+ }
}
static void selectCommand(redisClient *c) {
/* expect zsetnum input keys to be given */
zsetnum = atoi(c->argv[2]->ptr);
if (zsetnum < 1) {
- addReplySds(c,sdsnew("-ERR at least 1 input key is needed for ZUNION/ZINTER\r\n"));
+ addReplySds(c,sdsnew("-ERR at least 1 input key is needed for ZUNIONSTORE/ZINTERSTORE\r\n"));
return;
}
zfree(src);
}
-static void zunionCommand(redisClient *c) {
+static void zunionstoreCommand(redisClient *c) {
zunionInterGenericCommand(c,c->argv[1], REDIS_OP_UNION);
}
-static void zinterCommand(redisClient *c) {
+static void zinterstoreCommand(redisClient *c) {
zunionInterGenericCommand(c,c->argv[1], REDIS_OP_INTER);
}
}
}
+static sds catAppendOnlyGenericCommand(sds buf, int argc, robj **argv) {
+ int j;
+ buf = sdscatprintf(buf,"*%d\r\n",argc);
+ for (j = 0; j < argc; j++) {
+ robj *o = getDecodedObject(argv[j]);
+ buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
+ buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
+ buf = sdscatlen(buf,"\r\n",2);
+ decrRefCount(o);
+ }
+ return buf;
+}
+
+static sds catAppendOnlyExpireAtCommand(sds buf, robj *key, robj *seconds) {
+ int argc = 3;
+ long when;
+ robj *argv[3];
+
+ /* Make sure we can use strtol */
+ seconds = getDecodedObject(seconds);
+ when = time(NULL)+strtol(seconds->ptr,NULL,10);
+ decrRefCount(seconds);
+
+ argv[0] = createStringObject("EXPIREAT",8);
+ argv[1] = key;
+ argv[2] = createObject(REDIS_STRING,
+ sdscatprintf(sdsempty(),"%ld",when));
+ buf = catAppendOnlyGenericCommand(buf, argc, argv);
+ decrRefCount(argv[0]);
+ decrRefCount(argv[2]);
+ return buf;
+}
+
static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc) {
sds buf = sdsempty();
- int j;
robj *tmpargv[3];
/* The DB this command was targetting is not the same as the last command
server.appendseldb = dictid;
}
- /* "Fix" the argv vector if the command is EXPIRE. We want to translate
- * EXPIREs into EXPIREATs calls */
if (cmd->proc == expireCommand) {
- long when;
-
- tmpargv[0] = createStringObject("EXPIREAT",8);
+ /* Translate EXPIRE into EXPIREAT */
+ buf = catAppendOnlyExpireAtCommand(buf,argv[1],argv[2]);
+ } else if (cmd->proc == setexCommand) {
+ /* Translate SETEX to SET and EXPIREAT */
+ tmpargv[0] = createStringObject("SET",3);
tmpargv[1] = argv[1];
- incrRefCount(argv[1]);
- when = time(NULL)+strtol(argv[2]->ptr,NULL,10);
- tmpargv[2] = createObject(REDIS_STRING,
- sdscatprintf(sdsempty(),"%ld",when));
- argv = tmpargv;
- }
-
- /* Append the actual command */
- buf = sdscatprintf(buf,"*%d\r\n",argc);
- for (j = 0; j < argc; j++) {
- robj *o = argv[j];
-
- o = getDecodedObject(o);
- buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
- buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
- buf = sdscatlen(buf,"\r\n",2);
- decrRefCount(o);
- }
-
- /* Free the objects from the modified argv for EXPIREAT */
- if (cmd->proc == expireCommand) {
- for (j = 0; j < 3; j++)
- decrRefCount(argv[j]);
+ tmpargv[2] = argv[3];
+ buf = catAppendOnlyGenericCommand(buf,3,tmpargv);
+ decrRefCount(tmpargv[0]);
+ buf = catAppendOnlyExpireAtCommand(buf,argv[1],argv[2]);
+ } else {
+ buf = catAppendOnlyGenericCommand(buf,argc,argv);
}
/* Append to the AOF buffer. This will be flushed on disk just before
return 1;
}
-/* Preload keys needed for the ZUNION and ZINTER commands. */
-static void zunionInterBlockClientOnSwappedKeys(redisClient *c) {
+/* Preload keys for any command with first, last and step values for
+ * the command keys prototype, as defined in the command table. */
+static void waitForMultipleSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv) {
+ int j, last;
+ if (cmd->vm_firstkey == 0) return;
+ last = cmd->vm_lastkey;
+ if (last < 0) last = argc+last;
+ for (j = cmd->vm_firstkey; j <= last; j += cmd->vm_keystep) {
+ redisAssert(j < argc);
+ waitForSwappedKey(c,argv[j]);
+ }
+}
+
+/* Preload keys needed for the ZUNIONSTORE and ZINTERSTORE commands.
+ * Note that the number of keys to preload is user-defined, so we need to
+ * apply a sanity check against argc. */
+static void zunionInterBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv) {
int i, num;
- num = atoi(c->argv[2]->ptr);
+ REDIS_NOTUSED(cmd);
+
+ num = atoi(argv[2]->ptr);
+ if (num > (argc-3)) return;
for (i = 0; i < num; i++) {
- waitForSwappedKey(c,c->argv[3+i]);
+ waitForSwappedKey(c,argv[3+i]);
+ }
+}
+
+/* Preload keys needed to execute the entire MULTI/EXEC block.
+ *
+ * This function is called by blockClientOnSwappedKeys when EXEC is issued,
+ * and will block the client when any command requires a swapped out value. */
+static void execBlockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd, int argc, robj **argv) {
+ int i, margc;
+ struct redisCommand *mcmd;
+ robj **margv;
+ REDIS_NOTUSED(cmd);
+ REDIS_NOTUSED(argc);
+ REDIS_NOTUSED(argv);
+
+ if (!(c->flags & REDIS_MULTI)) return;
+ for (i = 0; i < c->mstate.count; i++) {
+ mcmd = c->mstate.commands[i].cmd;
+ margc = c->mstate.commands[i].argc;
+ margv = c->mstate.commands[i].argv;
+
+ if (mcmd->vm_preload_proc != NULL) {
+ mcmd->vm_preload_proc(c,mcmd,margc,margv);
+ } else {
+ waitForMultipleSwappedKeys(c,mcmd,margc,margv);
+ }
}
}
*
* Return 1 if the client is marked as blocked, 0 if the client can
* continue as the keys it is going to access appear to be in memory. */
-static int blockClientOnSwappedKeys(struct redisCommand *cmd, redisClient *c) {
- int j, last;
-
+static int blockClientOnSwappedKeys(redisClient *c, struct redisCommand *cmd) {
if (cmd->vm_preload_proc != NULL) {
- cmd->vm_preload_proc(c);
+ cmd->vm_preload_proc(c,cmd,c->argc,c->argv);
} else {
- if (cmd->vm_firstkey == 0) return 0;
- last = cmd->vm_lastkey;
- if (last < 0) last = c->argc+last;
- for (j = cmd->vm_firstkey; j <= last; j += cmd->vm_keystep)
- waitForSwappedKey(c,c->argv[j]);
+ waitForMultipleSwappedKeys(c,cmd,c->argc,c->argv);
}
/* If the client was blocked for at least one key, mark it as blocked. */
/* ================================= 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) */
+static 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];
+}
+
+static 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".
+ */
+static 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);
+}
+
+static 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. */
+static 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) {
+ robj *key, *o;
+ time_t expiretime;
+
+ memset(digest,0,20); /* This key-val digest */
+ key = dictGetEntryKey(de);
+ mixObjectDigest(digest,key);
+ if (!server.vm_enabled || key->storage == REDIS_VM_MEMORY ||
+ key->storage == REDIS_VM_SWAPPING) {
+ o = dictGetEntryVal(de);
+ incrRefCount(o);
+ } else {
+ o = vmPreviewObject(key);
+ }
+ aux = htonl(o->type);
+ mixDigest(digest,&aux,sizeof(aux));
+ expiretime = getExpire(db,key);
+
+ /* Save the key and associated value */
+ if (o->type == REDIS_STRING) {
+ mixObjectDigest(digest,o);
+ } else if (o->type == REDIS_LIST) {
+ list *list = o->ptr;
+ listNode *ln;
+ listIter li;
+
+ listRewind(list,&li);
+ while((ln = listNext(&li))) {
+ robj *eleobj = listNodeValue(ln);
+
+ mixObjectDigest(digest,eleobj);
+ }
+ } 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) {
+ hashIterator *hi;
+ robj *obj;
+
+ hi = hashInitIterator(o);
+ while (hashNext(hi) != REDIS_ERR) {
+ unsigned char eledigest[20];
+
+ memset(eledigest,0,20);
+ obj = hashCurrent(hi,REDIS_HASH_KEY);
+ mixObjectDigest(eledigest,obj);
+ decrRefCount(obj);
+ obj = hashCurrent(hi,REDIS_HASH_VALUE);
+ mixObjectDigest(eledigest,obj);
+ decrRefCount(obj);
+ xorDigest(digest,eledigest,20);
+ }
+ hashReleaseIterator(hi);
+ } else {
+ redisPanic("Unknown object type");
+ }
+ decrRefCount(o);
+ /* 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);
+ }
+ dictReleaseIterator(di);
+ }
+}
+
static void debugCommand(redisClient *c) {
if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
*((char*)-1) = 'x';
dictAdd(c->db->dict,key,val);
}
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"));
projects / redis.git / blobdiff