DEBUG should not be flagged as w otherwise we can not call DEBUG DIGEST and other...

[redis.git] / src / sort.c

diff --git a/src/sort.c b/src/sort.c
index f70810b9baeeef1a66eb4b6500c0f5d25c8e2e17..3f02e49a709a4cbf32c6d4ba92480de55d218f05 100644 (file)
--- a/src/sort.c
+++ b/src/sort.c
@@ -1,5 +1,6 @@
 #include "redis.h"
 #include "pqsort.h" /* Partial qsort for SORT+LIMIT */
+#include <math.h> /* isnan() */
 
 redisSortOperation *createSortOperation(int type, robj *pattern) {
     redisSortOperation *so = zmalloc(sizeof(*so));
@@ -102,7 +103,10 @@ int sortCompare(const void *s1, const void *s2) {
         } else if (so1->u.score < so2->u.score) {
             cmp = -1;
         } else {
-            cmp = 0;
+            /* Objects have the same score, but we don't want the comparison
+             * to be undefined, so we compare objects lexicographycally.
+             * This way the result of SORT is deterministic. */
+            cmp = compareStringObjects(so1->obj,so2->obj);
         }
     } else {
         /* Alphanumeric sorting */
@@ -133,19 +137,16 @@ void sortCommand(redisClient *c) {
     list *operations;
     unsigned int outputlen = 0;
     int desc = 0, alpha = 0;
-    int limit_start = 0, limit_count = -1, start, end;
+    long limit_start = 0, limit_count = -1, start, end;
     int j, dontsort = 0, vectorlen;
     int getop = 0; /* GET operation counter */
+    int int_convertion_error = 0;
     robj *sortval, *sortby = NULL, *storekey = NULL;
     redisSortObject *vector; /* Resulting vector to sort */
 
     /* Lookup the key to sort. It must be of the right types */
     sortval = lookupKeyRead(c->db,c->argv[1]);
-    if (sortval == NULL) {
-        addReply(c,shared.emptymultibulk);
-        return;
-    }
-    if (sortval->type != REDIS_SET && sortval->type != REDIS_LIST &&
+    if (sortval && sortval->type != REDIS_SET && sortval->type != REDIS_LIST &&
         sortval->type != REDIS_ZSET)
     {
         addReply(c,shared.wrongtypeerr);
@@ -161,7 +162,10 @@ void sortCommand(redisClient *c) {
     /* Now we need to protect sortval incrementing its count, in the future
      * SORT may have options able to overwrite/delete keys during the sorting
      * and the sorted key itself may get destroied */
-    incrRefCount(sortval);
+    if (sortval)
+        incrRefCount(sortval);
+    else
+        sortval = createListObject();
 
     /* The SORT command has an SQL-alike syntax, parse it */
     while(j < c->argc) {
@@ -173,8 +177,8 @@ void sortCommand(redisClient *c) {
         } else if (!strcasecmp(c->argv[j]->ptr,"alpha")) {
             alpha = 1;
         } else if (!strcasecmp(c->argv[j]->ptr,"limit") && leftargs >= 2) {
-            limit_start = atoi(c->argv[j+1]->ptr);
-            limit_count = atoi(c->argv[j+2]->ptr);
+            if ((getLongFromObjectOrReply(c, c->argv[j+1], &limit_start, NULL) != REDIS_OK) ||
+                (getLongFromObjectOrReply(c, c->argv[j+2], &limit_count, NULL) != REDIS_OK)) return;
             j+=2;
         } else if (!strcasecmp(c->argv[j]->ptr,"store") && leftargs >= 1) {
             storekey = c->argv[j+1];
@@ -199,8 +203,18 @@ void sortCommand(redisClient *c) {
         j++;
     }
 
+    /* If we have STORE we need to force sorting for deterministic output
+     * and replication. We use alpha sorting since this is guaranteed to
+     * work with any input. */
+    if (storekey && dontsort) {
+        dontsort = 0;
+        alpha = 1;
+        sortby = NULL;
+    }
+
     /* Destructively convert encoded sorted sets for SORT. */
-    if (sortval->type == REDIS_ZSET) zsetConvert(sortval, REDIS_ENCODING_SKIPLIST);
+    if (sortval->type == REDIS_ZSET)
+        zsetConvert(sortval, REDIS_ENCODING_SKIPLIST);
 
     /* Load the sorting vector with all the objects to sort */
     switch(sortval->type) {
@@ -266,7 +280,14 @@ void sortCommand(redisClient *c) {
                 if (sortby) vector[j].u.cmpobj = getDecodedObject(byval);
             } else {
                 if (byval->encoding == REDIS_ENCODING_RAW) {
-                    vector[j].u.score = strtod(byval->ptr,NULL);
+                    char *eptr;
+
+                    vector[j].u.score = strtod(byval->ptr,&eptr);
+                    if (eptr[0] != '\0' || errno == ERANGE ||
+                        isnan(vector[j].u.score))
+                    {
+                        int_convertion_error = 1;
+                    }
                 } else if (byval->encoding == REDIS_ENCODING_INT) {
                     /* Don't need to decode the object if it's
                      * integer-encoded (the only encoding supported) so
@@ -295,6 +316,7 @@ void sortCommand(redisClient *c) {
     }
     if (end >= vectorlen) end = vectorlen-1;
 
+    server.sort_dontsort = dontsort;
     if (dontsort == 0) {
         server.sort_desc = desc;
         server.sort_alpha = alpha;
@@ -308,7 +330,9 @@ void sortCommand(redisClient *c) {
     /* Send command output to the output buffer, performing the specified
      * GET/DEL/INCR/DECR operations if any. */
     outputlen = getop ? getop*(end-start+1) : end-start+1;
-    if (storekey == NULL) {
+    if (int_convertion_error) {
+        addReplyError(c,"One or more scores can't be converted into double");
+    } else if (storekey == NULL) {
         /* STORE option not specified, sent the sorting result to client */
         addReplyMultiBulkLen(c,outputlen);
         for (j = start; j <= end; j++) {
@@ -367,12 +391,14 @@ void sortCommand(redisClient *c) {
                 }
             }
         }
-        setKey(c->db,storekey,sobj);
+        if (outputlen) {
+            setKey(c->db,storekey,sobj);
+            server.dirty += outputlen;
+        } else if (dbDelete(c->db,storekey)) {
+            signalModifiedKey(c->db,storekey);
+            server.dirty++;
+        }
         decrRefCount(sobj);
-        /* Note: we add 1 because the DB is dirty anyway since even if the
-         * SORT result is empty a new key is set and maybe the old content
-         * replaced. */
-        server.dirty += 1+outputlen;
         addReplyLongLong(c,outputlen);
     }