return REDIS_OK;
}
+/*-----------------------------------------------------------------------------
+ * Ziplist-backed sorted set API
+ *----------------------------------------------------------------------------*/
+
+double zzlGetScore(unsigned char *sptr) {
+ unsigned char *vstr;
+ unsigned int vlen;
+ long long vlong;
+ char buf[128];
+ double score;
+
+ redisAssert(sptr != NULL);
+ redisAssert(ziplistGet(sptr,&vstr,&vlen,&vlong));
+
+ if (vstr) {
+ memcpy(buf,vstr,vlen);
+ buf[vlen] = '\0';
+ score = strtod(buf,NULL);
+ } else {
+ score = vlong;
+ }
+
+ return score;
+}
+
+/* Compare element in sorted set with given element. */
+int zzlCompareElements(unsigned char *eptr, unsigned char *cstr, unsigned int clen) {
+ unsigned char *vstr;
+ unsigned int vlen;
+ long long vlong;
+ unsigned char vbuf[32];
+ int minlen, cmp;
+
+ redisAssert(ziplistGet(eptr,&vstr,&vlen,&vlong));
+ if (vstr == NULL) {
+ /* Store string representation of long long in buf. */
+ vlen = ll2string((char*)vbuf,sizeof(vbuf),vlong);
+ vstr = vbuf;
+ }
+
+ minlen = (vlen < clen) ? vlen : clen;
+ cmp = memcmp(vstr,cstr,minlen);
+ if (cmp == 0) return vlen-clen;
+ return cmp;
+}
+
+unsigned char *zzlFind(robj *zobj, robj *ele, double *score) {
+ unsigned char *zl = zobj->ptr;
+ unsigned char *eptr = ziplistIndex(zl,0), *sptr;
+
+ ele = getDecodedObject(ele);
+ while (eptr != NULL) {
+ sptr = ziplistNext(zl,eptr);
+ redisAssert(sptr != NULL);
+
+ if (ziplistCompare(eptr,ele->ptr,sdslen(ele->ptr))) {
+ /* Matching element, pull out score. */
+ *score = zzlGetScore(sptr);
+ decrRefCount(ele);
+ return eptr;
+ }
+
+ /* Move to next element. */
+ eptr = ziplistNext(zl,sptr);
+ }
+
+ decrRefCount(ele);
+ return NULL;
+}
+
+/* Delete (element,score) pair from ziplist. Use local copy of eptr because we
+ * don't want to modify the one given as argument. */
+int zzlDelete(robj *zobj, unsigned char *eptr) {
+ unsigned char *zl = zobj->ptr;
+ unsigned char *p = eptr;
+
+ /* TODO: add function to ziplist API to delete N elements from offset. */
+ zl = ziplistDelete(zl,&p);
+ zl = ziplistDelete(zl,&p);
+ zobj->ptr = zl;
+ return REDIS_OK;
+}
+
+int zzlInsertAt(robj *zobj, robj *ele, double score, unsigned char *eptr) {
+ unsigned char *zl = zobj->ptr;
+ unsigned char *sptr;
+ char scorebuf[128];
+ int scorelen;
+ int offset;
+
+ redisAssert(ele->encoding == REDIS_ENCODING_RAW);
+ scorelen = d2string(scorebuf,sizeof(scorebuf),score);
+ if (eptr == NULL) {
+ zl = ziplistPush(zl,ele->ptr,sdslen(ele->ptr),ZIPLIST_TAIL);
+ zl = ziplistPush(zl,(unsigned char*)scorebuf,scorelen,ZIPLIST_TAIL);
+ } else {
+ /* Keep offset relative to zl, as it might be re-allocated. */
+ offset = eptr-zl;
+ zl = ziplistInsert(zl,eptr,ele->ptr,sdslen(ele->ptr));
+ eptr = zl+offset;
+
+ /* Insert score after the element. */
+ redisAssert((sptr = ziplistNext(zl,eptr)) != NULL);
+ zl = ziplistInsert(zl,sptr,(unsigned char*)scorebuf,scorelen);
+ }
+
+ zobj->ptr = zl;
+ return REDIS_OK;
+}
+
+/* Insert (element,score) pair in ziplist. This function assumes the element is
+ * not yet present in the list. */
+int zzlInsert(robj *zobj, robj *ele, double score) {
+ unsigned char *zl = zobj->ptr;
+ unsigned char *eptr = ziplistIndex(zl,0), *sptr;
+ double s;
+ int insert = 0;
+
+ ele = getDecodedObject(ele);
+ while (eptr != NULL) {
+ sptr = ziplistNext(zl,eptr);
+ redisAssert(sptr != NULL);
+ s = zzlGetScore(sptr);
+
+ if (s > score) {
+ /* First element with score larger than score for element to be
+ * inserted. This means we should take its spot in the list to
+ * maintain ordering. */
+ insert = 1;
+ } else if (s == score) {
+ /* Ensure lexicographical ordering for elements. */
+ if (zzlCompareElements(eptr,ele->ptr,sdslen(ele->ptr)) < 0)
+ insert = 1;
+ }
+
+ if (insert) {
+ zzlInsertAt(zobj,ele,score,eptr);
+ break;
+ }
+
+ /* Move to next element. */
+ eptr = ziplistNext(zl,sptr);
+ }
+
+ /* Push on tail of list when it was not yet inserted. */
+ if (!insert)
+ zzlInsertAt(zobj,ele,score,eptr);
+
+ decrRefCount(ele);
+ return REDIS_OK;
+}
/*-----------------------------------------------------------------------------
* Sorted set commands
/* This generic command implements both ZADD and ZINCRBY. */
void zaddGenericCommand(redisClient *c, robj *key, robj *ele, double score, int incr) {
- robj *zsetobj;
- zset *zs;
- zskiplistNode *znode;
-
- zsetobj = lookupKeyWrite(c->db,key);
- if (zsetobj == NULL) {
- zsetobj = createZsetObject();
- dbAdd(c->db,key,zsetobj);
+ static char *nanerr = "resulting score is not a number (NaN)";
+ robj *zobj;
+ robj *curobj;
+ double curscore = 0.0;
+
+ zobj = lookupKeyWrite(c->db,key);
+ if (zobj == NULL) {
+ zobj = createZsetZiplistObject();
+ dbAdd(c->db,key,zobj);
} else {
- if (zsetobj->type != REDIS_ZSET) {
+ if (zobj->type != REDIS_ZSET) {
addReply(c,shared.wrongtypeerr);
return;
}
}
- zs = zsetobj->ptr;
- /* Since both ZADD and ZINCRBY are implemented here, we need to increment
- * the score first by the current score if ZINCRBY is called. */
- if (incr) {
- /* Read the old score. If the element was not present starts from 0 */
- dictEntry *de = dictFind(zs->dict,ele);
- if (de != NULL)
- score += *(double*)dictGetEntryVal(de);
-
- if (isnan(score)) {
- addReplyError(c,"resulting score is not a number (NaN)");
- /* Note that we don't need to check if the zset may be empty and
- * should be removed here, as we can only obtain Nan as score if
- * there was already an element in the sorted set. */
- return;
- }
- }
+ if (zobj->encoding == REDIS_ENCODING_ZIPLIST) {
+ unsigned char *eptr;
- /* We need to remove and re-insert the element when it was already present
- * in the dictionary, to update the skiplist. Note that we delay adding a
- * pointer to the score because we want to reference the score in the
- * skiplist node. */
- if (dictAdd(zs->dict,ele,NULL) == DICT_OK) {
- dictEntry *de;
+ if ((eptr = zzlFind(zobj,ele,&curscore)) != NULL) {
+ if (incr) {
+ score += curscore;
+ if (isnan(score)) {
+ addReplyError(c,nanerr);
+ /* Don't need to check if the sorted set is empty, because
+ * we know it has at least one element. */
+ return;
+ }
+ }
- /* New element */
- incrRefCount(ele); /* added to hash */
- znode = zslInsert(zs->zsl,score,ele);
- incrRefCount(ele); /* added to skiplist */
+ /* Remove and re-insert when score changed. */
+ if (score != curscore) {
+ redisAssert(zzlDelete(zobj,eptr) == REDIS_OK);
+ redisAssert(zzlInsert(zobj,ele,score) == REDIS_OK);
- /* Update the score in the dict entry */
- de = dictFind(zs->dict,ele);
- redisAssert(de != NULL);
- dictGetEntryVal(de) = &znode->score;
- signalModifiedKey(c->db,c->argv[1]);
- server.dirty++;
- if (incr)
- addReplyDouble(c,score);
- else
- addReply(c,shared.cone);
- } else {
+ signalModifiedKey(c->db,key);
+ server.dirty++;
+ }
+
+ if (incr) /* ZINCRBY */
+ addReplyDouble(c,score);
+ else /* ZADD */
+ addReply(c,shared.czero);
+ } else {
+ redisAssert(zzlInsert(zobj,ele,score) == REDIS_OK);
+
+ signalModifiedKey(c->db,key);
+ server.dirty++;
+
+ if (incr) /* ZINCRBY */
+ addReplyDouble(c,score);
+ else /* ZADD */
+ addReply(c,shared.cone);
+ }
+ } else if (zobj->encoding == REDIS_ENCODING_RAW) {
+ zset *zs = zobj->ptr;
+ zskiplistNode *znode;
dictEntry *de;
- robj *curobj;
- double *curscore;
- int deleted;
- /* Update score */
de = dictFind(zs->dict,ele);
- redisAssert(de != NULL);
- curobj = dictGetEntryKey(de);
- curscore = dictGetEntryVal(de);
-
- /* When the score is updated, reuse the existing string object to
- * prevent extra alloc/dealloc of strings on ZINCRBY. */
- if (score != *curscore) {
- deleted = zslDelete(zs->zsl,*curscore,curobj);
- redisAssert(deleted != 0);
- znode = zslInsert(zs->zsl,score,curobj);
- incrRefCount(curobj);
-
- /* Update the score in the current dict entry */
- dictGetEntryVal(de) = &znode->score;
- signalModifiedKey(c->db,c->argv[1]);
+ if (de != NULL) {
+ curobj = dictGetEntryKey(de);
+ curscore = *(double*)dictGetEntryVal(de);
+
+ if (incr) {
+ score += curscore;
+ if (isnan(score)) {
+ addReplyError(c,nanerr);
+ /* Don't need to check if the sorted set is empty, because
+ * we know it has at least one element. */
+ return;
+ }
+ }
+
+ /* Remove and re-insert when score changed. We can safely delete
+ * the key object from the skiplist, since the dictionary still has
+ * a reference to it. */
+ if (score != curscore) {
+ redisAssert(zslDelete(zs->zsl,curscore,curobj));
+ znode = zslInsert(zs->zsl,score,curobj);
+ incrRefCount(curobj); /* Re-inserted in skiplist. */
+ dictGetEntryVal(de) = &znode->score; /* Update score ptr. */
+
+ signalModifiedKey(c->db,key);
+ server.dirty++;
+ }
+
+ if (incr) /* ZINCRBY */
+ addReplyDouble(c,score);
+ else /* ZADD */
+ addReply(c,shared.czero);
+ } else {
+ znode = zslInsert(zs->zsl,score,ele);
+ incrRefCount(ele); /* Inserted in skiplist. */
+ redisAssert(dictAdd(zs->dict,ele,&znode->score) == DICT_OK);
+ incrRefCount(ele); /* Added to dictionary. */
+
+ signalModifiedKey(c->db,key);
server.dirty++;
+
+ if (incr) /* ZINCRBY */
+ addReplyDouble(c,score);
+ else /* ZADD */
+ addReply(c,shared.cone);
}
- if (incr)
- addReplyDouble(c,score);
- else
- addReply(c,shared.czero);
+ } else {
+ redisPanic("Unknown sorted set encoding");
}
}
projects / redis.git / commitdiff
