add a new SET option KEEPTTL that doesn't remove expire time

src/bitops.c

@@ -754,7 +754,7 @@ void bitopCommand(client *c) {
     /* Store the computed value into the target key */
     if (maxlen) {
         o = createObject(OBJ_STRING,res);
-        setKey(c->db,targetkey,o);
+        setKey(c->db,targetkey,o,0);
         notifyKeyspaceEvent(NOTIFY_STRING,"set",targetkey,c->db->id);
         decrRefCount(o);
     } else if (dbDelete(c->db,targetkey)) {

src/db.c

@@ -219,14 +219,14 @@ void dbOverwrite(redisDb *db, robj *key, robj *val) {
  * 3) The expire time of the key is reset (the key is made persistent).
  *
  * All the new keys in the database should be created via this interface. */
-void setKey(redisDb *db, robj *key, robj *val) {
+void setKey(redisDb *db, robj *key, robj *val, int keepttl) {
     if (lookupKeyWrite(db,key) == NULL) {
         dbAdd(db,key,val);
     } else {
         dbOverwrite(db,key,val);
     }
     incrRefCount(val);
-    removeExpire(db,key);
+    if (!keepttl) removeExpire(db,key);
     signalModifiedKey(db,key);
 }
 

src/geo.c

@@ -657,7 +657,7 @@ void georadiusGeneric(client *c, int flags) {
 
         if (returned_items) {
             zsetConvertToZiplistIfNeeded(zobj,maxelelen);
-            setKey(c->db,storekey,zobj);
+            setKey(c->db,storekey,zobj,0);
             decrRefCount(zobj);
             notifyKeyspaceEvent(NOTIFY_ZSET,"georadiusstore",storekey,
                                 c->db->id);

src/module.c

@@ -2107,7 +2107,7 @@ RedisModuleString *RM_RandomKey(RedisModuleCtx *ctx) {
 int RM_StringSet(RedisModuleKey *key, RedisModuleString *str) {
     if (!(key->mode & REDISMODULE_WRITE) || key->iter) return REDISMODULE_ERR;
     RM_DeleteKey(key);
-    setKey(key->db,key->key,str);
+    setKey(key->db,key->key,str,0);
     key->value = str;
     return REDISMODULE_OK;
 }
@@ -2187,7 +2187,7 @@ int RM_StringTruncate(RedisModuleKey *key, size_t newlen) {
     if (key->value == NULL) {
         /* Empty key: create it with the new size. */
         robj *o = createObject(OBJ_STRING,sdsnewlen(NULL, newlen));
-        setKey(key->db,key->key,o);
+        setKey(key->db,key->key,o,0);
         key->value = o;
         decrRefCount(o);
     } else {
@@ -3571,7 +3571,7 @@ int RM_ModuleTypeSetValue(RedisModuleKey *key, moduleType *mt, void *value) {
     if (!(key->mode & REDISMODULE_WRITE) || key->iter) return REDISMODULE_ERR;
     RM_DeleteKey(key);
     robj *o = createModuleObject(mt,value);
-    setKey(key->db,key->key,o);
+    setKey(key->db,key->key,o,0);
     decrRefCount(o);
     key->value = o;
     return REDISMODULE_OK;

src/server.h

@@ -2025,7 +2025,7 @@ int objectSetLRUOrLFU(robj *val, long long lfu_freq, long long lru_idle,
 #define LOOKUP_NOTOUCH (1<<0)
 void dbAdd(redisDb *db, robj *key, robj *val);
 void dbOverwrite(redisDb *db, robj *key, robj *val);
-void setKey(redisDb *db, robj *key, robj *val);
+void setKey(redisDb *db, robj *key, robj *val, int keepttl);
 int dbExists(redisDb *db, robj *key);
 robj *dbRandomKey(redisDb *db);
 int dbSyncDelete(redisDb *db, robj *key);

src/sort.c

@@ -570,7 +570,7 @@ void sortCommand(client *c) {
             }
         }
         if (outputlen) {
-            setKey(c->db,storekey,sobj);
+            setKey(c->db,storekey,sobj,0);
             notifyKeyspaceEvent(NOTIFY_LIST,"sortstore",storekey,
                                 c->db->id);
             server.dirty += outputlen;

src/t_string.c

@@ -46,7 +46,7 @@ static int checkStringLength(client *c, long long size) {
  * options and variants. This function is called in order to implement the
  * following commands: SET, SETEX, PSETEX, SETNX.
  *
- * 'flags' changes the behavior of the command (NX or XX, see belove).
+ * 'flags' changes the behavior of the command (NX or XX, see below).
  *
  * 'expire' represents an expire to set in form of a Redis object as passed
  * by the user. It is interpreted according to the specified 'unit'.
@@ -63,6 +63,7 @@ static int checkStringLength(client *c, long long size) {
 #define OBJ_SET_XX (1<<1)          /* Set if key exists. */
 #define OBJ_SET_EX (1<<2)          /* Set if time in seconds is given */
 #define OBJ_SET_PX (1<<3)          /* Set if time in ms in given */
+#define OBJ_SET_KEEPTTL (1<<4)     /* Set and keep the ttl */
 
 void setGenericCommand(client *c, int flags, robj *key, robj *val, robj *expire, int unit, robj *ok_reply, robj *abort_reply) {
     long long milliseconds = 0; /* initialized to avoid any harmness warning */
@@ -83,7 +84,7 @@ void setGenericCommand(client *c, int flags, robj *key, robj *val, robj *expire,
         addReply(c, abort_reply ? abort_reply : shared.null[c->resp]);
         return;
     }
-    setKey(c->db,key,val);
+    setKey(c->db,key,val,flags & OBJ_SET_KEEPTTL);
     server.dirty++;
     if (expire) setExpire(c,c->db,key,mstime()+milliseconds);
     notifyKeyspaceEvent(NOTIFY_STRING,"set",key,c->db->id);
@@ -92,7 +93,7 @@ void setGenericCommand(client *c, int flags, robj *key, robj *val, robj *expire,
     addReply(c, ok_reply ? ok_reply : shared.ok);
 }
 
-/* SET key value [NX] [XX] [EX <seconds>] [PX <milliseconds>] */
+/* SET key value [NX] [XX] [KEEPTTL] [EX <seconds>] [PX <milliseconds>] */
 void setCommand(client *c) {
     int j;
     robj *expire = NULL;
@@ -113,8 +114,13 @@ void setCommand(client *c) {
                    !(flags & OBJ_SET_NX))
         {
             flags |= OBJ_SET_XX;
+        } else if (!strcasecmp(c->argv[j]->ptr,"KEEPTTL") &&
+                   !(flags & OBJ_SET_EX) && !(flags & OBJ_SET_PX))
+        {
+            flags |= OBJ_SET_KEEPTTL;
         } else if ((a[0] == 'e' || a[0] == 'E') &&
                    (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
+                   !(flags & OBJ_SET_KEEPTTL) &&
                    !(flags & OBJ_SET_PX) && next)
         {
             flags |= OBJ_SET_EX;
@@ -123,6 +129,7 @@ void setCommand(client *c) {
             j++;
         } else if ((a[0] == 'p' || a[0] == 'P') &&
                    (a[1] == 'x' || a[1] == 'X') && a[2] == '\0' &&
+                   !(flags & OBJ_SET_KEEPTTL) &&
                    !(flags & OBJ_SET_EX) && next)
         {
             flags |= OBJ_SET_PX;
@@ -176,7 +183,7 @@ void getCommand(client *c) {
 void getsetCommand(client *c) {
     if (getGenericCommand(c) == C_ERR) return;
     c->argv[2] = tryObjectEncoding(c->argv[2]);
-    setKey(c->db,c->argv[1],c->argv[2]);
+    setKey(c->db,c->argv[1],c->argv[2],0);
     notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[1],c->db->id);
     server.dirty++;
 }
@@ -321,7 +328,7 @@ void msetGenericCommand(client *c, int nx) {
 
     for (j = 1; j < c->argc; j += 2) {
         c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
-        setKey(c->db,c->argv[j],c->argv[j+1]);
+        setKey(c->db,c->argv[j],c->argv[j+1],0);
         notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[j],c->db->id);
     }
     server.dirty += (c->argc-1)/2;

tests/unit/expire.tcl

@@ -219,4 +219,17 @@ start_server {tags {"expire"}} {
         set ttl [r ttl foo]
         assert {$ttl <= 98 && $ttl > 90}
     }
+
+    test {SET command will remove expire} {
+        r set foo bar EX 100
+        r set foo bar
+        r ttl foo
+    } {-1}
+
+    test {SET - use KEEPTTL option, TTL should not be removed} {
+        r set foo bar EX 100
+        r set foo bar KEEPTTL
+        set ttl [r ttl foo]
+        assert {$ttl <= 100 && $ttl > 90}
+    }
 }