Fix key extraction for z{union,inter}store

The previous implementation wasn't taking into account
the storage key in position 1 being a requirement (it
was only counting the source keys in positions 3 to N).

Fixes antirez/redis#1581
This commit is contained in:
Matt Stancliff 2014-03-07 16:32:04 -05:00
parent 0f2597092f
commit f0782a6e86

View File

@ -993,9 +993,23 @@ int *zunionInterGetKeys(struct redisCommand *cmd,robj **argv, int argc, int *num
*numkeys = 0;
return NULL;
}
keys = zmalloc(sizeof(int)*num);
/* Keys in z{union,inter}store come from two places:
argv[1] = storage key,
argv[3...n] = keys to intersect */
/* (num+1) is (argv[2] + 1) to account for argv[1] too */
keys = zmalloc(sizeof(int)*(num+1));
/* Add all key positions for argv[3...n] to keys[] */
for (i = 0; i < num; i++) keys[i] = 3+i;
*numkeys = num;
/* Now add the argv[1] key position (the storage key target)
to our list of command positions containing keys.
num is the number of source keys, but we initialized
keys[] to size num+1, so keys[num] is safe and valid and okay. */
keys[num] = 1;
*numkeys = num+1; /* Total keys = {union,inter} keys + storage key */
return keys;
}