-void substrCommand(redisClient *c) {
- robj *o;
- long start = atoi(c->argv[2]->ptr);
- long end = atoi(c->argv[3]->ptr);
- size_t rangelen, strlen;
- sds range;
-
- if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
- checkType(c,o,REDIS_STRING)) return;
-
- o = getDecodedObject(o);
- strlen = sdslen(o->ptr);
-
- /* convert negative indexes */
- if (start < 0) start = strlen+start;
- if (end < 0) end = strlen+end;
- if (start < 0) start = 0;
- if (end < 0) end = 0;
-
- /* indexes sanity checks */
- if (start > end || (size_t)start >= strlen) {
- /* Out of range start or start > end result in null reply */
- addReply(c,shared.nullbulk);
- decrRefCount(o);
- return;
- }
- if ((size_t)end >= strlen) end = strlen-1;
- rangelen = (end-start)+1;
-
- /* Return the result */
- addReplySds(c,sdscatprintf(sdsempty(),"$%zu\r\n",rangelen));
- range = sdsnewlen((char*)o->ptr+start,rangelen);
- addReplySds(c,range);
- addReply(c,shared.crlf);
- decrRefCount(o);
-}
-