Fixed arity detection of Redis command executed from Lua script. Error...

Fixed arity detection of Redis command executed from Lua script. Error reporting from Lua fixed. More work on the Redis reply to lua conversion code.

src/SCRIPTING.txt

+TODO:
+
+    redis('get',1) => crash
+    Fix multi bulk replies, redis('lrange', ...)

src/scripting.c

@@ -8,6 +8,8 @@
 char *redisProtocolToLuaType_Int(lua_State *lua, char *reply);
 char *redisProtocolToLuaType_Bulk(lua_State *lua, char *reply);
 char *redisProtocolToLuaType_Status(lua_State *lua, char *reply);
+char *redisProtocolToLuaType_Error(lua_State *lua, char *reply);
+char *redisProtocolToLuaType_MultiBulk(lua_State *lua, char *reply);
 
 /* Take a Redis reply in the Redis protocol format and convert it into a
  * Lua type. Thanks to this function, and the introduction of not connected
@@ -41,6 +43,12 @@ char *redisProtocolToLuaType(lua_State *lua, char* reply) {
     case '+':
         p = redisProtocolToLuaType_Status(lua,reply);
         break;
+    case '-':
+        p = redisProtocolToLuaType_Error(lua,reply);
+        break;
+    case '*':
+        p = redisProtocolToLuaType_MultiBulk(lua,reply);
+        break;
     }
     return p;
 }
@@ -75,6 +83,38 @@ char *redisProtocolToLuaType_Status(lua_State *lua, char *reply) {
     return p+2;
 }
 
+char *redisProtocolToLuaType_Error(lua_State *lua, char *reply) {
+    char *p = strchr(reply+1,'\r');
+
+    lua_newtable(lua);
+    lua_pushstring(lua,"err");
+    lua_pushlstring(lua,reply+1,p-reply-1);
+    lua_settable(lua,-3);
+    return p+2;
+}
+
+char *redisProtocolToLuaType_MultiBulk(lua_State *lua, char *reply) {
+    char *p = strchr(reply+1,'\r');
+    long long mbulklen;
+    int j = 0;
+
+    printf("--%s-- (%d)\n", reply,(int)(p-reply-1));
+    string2ll(reply+1,p-reply-1,&mbulklen);
+    p += 2;
+    if (mbulklen == -1) {
+        lua_pushnil(lua);
+        return p;
+    }
+    printf("BL: %lld\n", mbulklen);
+    lua_newtable(lua);
+    for (j = 0; j < mbulklen; j++) {
+        lua_pushnumber(lua,j);
+        p = redisProtocolToLuaType(lua,p);
+        lua_settable(lua,-3);
+    }
+    return p;
+}
+
 int luaRedisCommand(lua_State *lua) {
     int j, argc = lua_gettop(lua);
     struct redisCommand *cmd;
@@ -90,12 +130,18 @@ int luaRedisCommand(lua_State *lua) {
 
     /* Command lookup */
     cmd = lookupCommand(argv[0]->ptr);
-    if (!cmd) {
+    if (!cmd || ((cmd->arity > 0 && cmd->arity != argc) ||
+                   (argc < -cmd->arity)))
+    {
         for (j = 0; j < argc; j++) decrRefCount(argv[j]);
         zfree(argv);
         lua_newtable(lua);
         lua_pushstring(lua,"err");
-        lua_pushstring(lua,"Unknown Redis command called from Lua script");
+        if (cmd)
+            lua_pushstring(lua,
+                "Wrong number of args calling Redis command From Lua script");
+        else
+            lua_pushstring(lua,"Unknown Redis command called from Lua script");
         lua_settable(lua,-3);
         return 1;
     }
@@ -187,7 +233,8 @@ void luaReplyToRedisReply(redisClient *c, lua_State *lua) {
         lua_gettable(lua,-2);
         t = lua_type(lua,-1);
         if (t == LUA_TSTRING) {
-            addReplyError(c,(char*)lua_tostring(lua,-1));
+            addReplySds(c,sdscatprintf(sdsempty(),
+                    "-%s\r\n",(char*)lua_tostring(lua,-1)));
             lua_pop(lua,1);
         } else {
             void *replylen = addDeferredMultiBulkLength(c);