Merge branch 'master' of https://github.com/softlab-ntua/bencherl

app/IM/Makefile

@@ -0,0 +1,26 @@
+ERLC = erlc
+ERLC_OPTS =
+ERL = erl
+ERL_LIB_DIR = 
+
+SRCD = src
+EBIND = ebin-$(OTP)
+
+ERLF = $(wildcard $(SRCD)/*.erl)
+BEAMF = $(patsubst $(SRCD)/%.erl,$(EBIND)/%.beam,$(ERLF))
+
+.PHONY: app clean
+
+app: $(BEAMF)
+
+$(EBIND)/%.beam: $(SRCD)/%.erl
+	$(ERLC) $(ERLC_OPTS) -o$(EBIND) $<
+
+$(BEAMF): | $(EBIND)
+
+$(EBIND):
+	mkdir -p $(EBIND)
+
+clean:
+	$(RM) -rf ebin-*
+

app/IM/src/chat_db.erl

@@ -0,0 +1,354 @@
+%%%--------------------------------------------------------------------
+%%% CHAT_DB MODULE
+%%%
+%%% @author: Mario Moro Hernandez upon a design by Natalia Chechina
+%%% @copyright (C) 2014, RELEASE project
+%%% @doc
+%%%	Chat_DB module for the Distributed Erlang instant messenger (IM)
+%%%	application developed as a real benchmark for the Scalable 
+%%%	Distributed Erlang extension of the Erlang/OTP language.
+%%%
+%%%	This module implementes the functionality for the database that
+%%%	stores the chat sessions happening at a given time in a system
+%%%     similar to the system described in the Section 2 of the document
+%%%     "Instant Messenger Architectures Design Proposal".
+%%% @end 
+%%% Created: 1 Jul 2014 by Mario Moro Hernandez
+%%%--------------------------------------------------------------------
+
+-module(chat_db).
+-export([start/1, stop/1, chat_db/1]).
+
+
+%%%====================================================================
+%%% API
+%%%====================================================================
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Starts the chat sessions database.
+%%
+%% @spec start(DB_Name)
+%% @end
+%%---------------------------------------------------------------------
+start(DB_Name) ->
+    global:register_name(DB_Name, spawn(fun() -> chat_db(DB_Name) end)).
+
+%%--------------------------------------------------------------------
+%% @doc
+%% Stops the chat sessions database.
+%%
+%% @spec stop(DB_Name)
+%% @end
+%%--------------------------------------------------------------------
+stop(DB_Name) ->
+    destroy(DB_Name),
+    global:unregister_name(DB_Name).
+
+%%--------------------------------------------------------------------
+%% @doc
+%% chat_db is first stage of the database process. It creates an ets
+%% table after the atom specified as the argument DB_Name.
+%%
+%% @spec chat_db(DB_Name)
+%% @end
+%%--------------------------------------------------------------------
+chat_db(DB_Name) ->
+    case ets:info(DB_Name) of
+	undefined ->
+	    create(DB_Name),
+	    chat_db_loop(DB_Name);
+	_ ->
+	    chat_db_loop(DB_Name)
+    end.
+
+%%--------------------------------------------------------------------
+%% @doc
+%% chat_db_loop constitutes the database process, and offers an inter-
+%% face to interact with the ets table, allowing the input or retrieval
+%% of information concerning the chat sessions in the system. 
+%%
+%% @spec chat_db_local(DB_Name)
+%% @end
+%%--------------------------------------------------------------------
+chat_db_loop(DB_Name) ->
+    receive
+    	{From, add, Session_Name, Session_Pid, C1, C1_Pid, C2, C2_Pid} -> 
+	    add_session(DB_Name, Session_Name, Session_Pid, C1, C1_Pid, C2, C2_Pid),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! {session_added, ok}
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, remove, Session_Name} ->
+	    remove_session(DB_Name, Session_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! {session_removed, ok}
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, full_db} ->
+	    A = retrieve_db(DB_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! A
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, peak, Session_Name} ->
+	    S = peak_session(DB_Name, Session_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! S
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, peak_by_pid, Session_Pid} ->
+	    S = peak_session_pid(DB_Name, Session_Pid),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! S
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, session_pid, Session_Name} ->
+	    Pid = session_pid(DB_Name, Session_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! Pid
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, opened_sessions, Client} ->
+	    S = client_sessions(DB_Name, Client),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! S
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, recover, Target_DB_Name, Source_DB_Name} ->
+	    recover_db(Target_DB_Name, Source_DB_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! {recovered, ok}
+	    end,
+	    chat_db_loop(DB_Name);
+	{From, stop} ->
+	    stop(DB_Name),
+	    case From of
+		undefined ->
+		    ok;
+		_ ->
+		    From ! {chat_session_db_destroyed, ok}
+	    end;
+	Other ->
+		io:format("Something failed at Chat_DB. Received: ~p", [Other]),
+		chat_db_loop(DB_Name)
+    end.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Creates a new ets table -named Table_Name- to store the different
+%% chat sessions active in the system.
+%%
+%% @spec create(Table_Name) -> Table_Name | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+create(Table_Name) ->
+    ets:new(Table_Name, [set, named_table]).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Destroys ets table named Table_Name.
+%%
+%% @spec destroy(Table_Name) -> Table_Name | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+destroy(Table_Name) ->
+    ets:delete(Table_Name).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Adds a chat session to the chat sessions database.
+%%
+%% @spec add_session(Table_Name, Chat_Session_Pid,
+%%   	 	     Client_A, Client_B) -> true | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+add_session(Table_Name, Chat_Session_Name, Chat_Session_Pid, Client_A, Client_A_Pid, Client_B, Client_B_Pid) ->
+    ets:insert(Table_Name, {Chat_Session_Name, Chat_Session_Pid, Client_A, Client_A_Pid, Client_B, Client_B_Pid}).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Removes a chat session from the chat sessions database.
+%%
+%% @spec remove_session(Table_Name, Chat_Session_Pid) -> true | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+remove_session(Table_Name, Chat_Session_Name) ->
+    ets:delete(Table_Name, Chat_Session_Name).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Returns the contents of the whole database as a list of lists, where
+%% each of the nested lists is one session. (Not in use, only for debug
+%% purposes).
+%%
+%% @spec retrieve_db(Table_Name) ->
+%%                  [[session_1], ..., [session_n]] | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+retrieve_db(Table_Name) ->
+    ets:match(Table_Name, {'$0', '$1', '$2', '$3', '$4', '$5'}).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Returns a list containing the data of the session passed as argument.
+%%
+%% @spec peak_session(Table_Name, Session_Name) ->
+%%         [Session_Name, Session_Pid,
+%%          Client_A, Client_A_Pid, ClientB, Client_B_Pid] | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+peak_session(Table_Name, Session_Name) ->
+    L = ets:select(Table_Name, [{{'$0', '$1', '$2', '$3', '$4', '$5'},
+					 [{'==', '$0', Session_Name}],
+					 [['$0', '$1', '$2', '$3', '$4', '$5']]}]),
+    case L == [] of
+	true ->
+	    L;
+	false ->
+	    lists:last(L)
+    end.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Returns a list containing the data of the session corresponding to
+%% the pid passed as argument.
+%%
+%% @spec peak_session(Table_Name, Session_Pid) ->
+%%          [Session_Name, Session_Pid,
+%%          Client_A, Client_A_Pid, ClientB, Client_B_Pid] | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+peak_session_pid(Table_Name, Session_Pid) ->
+     L = ets:select(Table_Name, [{{'$0', '$1', '$2', '$3', '$4', '$5'},
+					 [{'==', '$1', Session_Pid}],
+					 [['$0', '$1', '$2', '$3', '$4', '$5']]}]),
+    case L == [] of
+	true ->
+	    L;
+	false ->
+	    lists:last(L)
+    end.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Returns the Pid of a given session passed as argument.
+%%
+%% @spec session_pid(Table_Name, Session_Name) -> Session_Pid | []
+%% @end
+%%---------------------------------------------------------------------
+session_pid(Table_Name, Session_Name) ->
+    L = ets:select(Table_Name, [{{'$0', '$1', '$2', '$3', '$4', '$5'},
+					 [{'==', '$0', Session_Name}],
+					 [['$1']]}]),
+    case L == [] of
+	true ->
+	    L;
+	false ->
+	    lists:last(lists:last(L))
+    end.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Returns a list containing all the sessions -and the information of
+%% these sessions- in which the client passed as the argument is one of
+%% participants. It returns an empty list if the client is not involved
+%% in any chat at the time of invocation.
+%%
+%% @spec retrieve_server(Table_Name, Session_Pid) ->
+%%                  [Session_1, ..., Session_k]  | []
+%% @end
+%%---------------------------------------------------------------------
+client_sessions(Table_Name, Client) ->
+    ets:safe_fixtable(Table_Name, true),
+    Sessions = opened_sessions(Table_Name, Client, ets:first(Table_Name), []),
+    ets:safe_fixtable(Table_Name, false),
+    Sessions.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Replicates the chat session table specified in the Source argument,
+%% in a new table with name Table_Name.
+%%
+%% @spec retrieve_server(Table_Name, Session_Pid) -> true | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+recover_db(Destination, Source) ->
+    ets:safe_fixtable(Source, true),
+    replicate(Source, Destination, ets:first(Source)),
+    ets:safe_fixtable(Source, false).
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Auxiliary function to the function client_sessions(Table_Name, Client).
+%% This function traverses the ets table containing all the conversations,
+%% and puts in a list all those in which the client is one of the
+%% participants.
+%%
+%% @spec opened_sessions(Table_Name, Client, Cursor, Sessions) ->
+%%                  [Session_1, ..., Session_n] | []
+%% @end
+%%---------------------------------------------------------------------
+opened_sessions(Table_Name, Client, Cursor, Sessions) -> 
+    case Cursor of
+	'$end_of_table' ->
+	    Sessions;
+	Cursor ->
+	    case (element(3, lists:last(ets:lookup(Table_Name, Cursor))) == Client) or
+		 (element(4, lists:last(ets:lookup(Table_Name, Cursor))) == Client) of
+		true ->
+		    opened_sessions(Table_Name, Client, ets:next(Table_Name, Cursor), 
+				    (Sessions ++ [lists:last(ets:lookup(Table_Name, Cursor))]));
+		false ->
+		    opened_sessions(Table_Name, Client, ets:next(Table_Name, Cursor), Sessions)
+	    end
+    end.
+
+%%---------------------------------------------------------------------
+%% @doc
+%% Auxiliary function to the function recover_db(Table_Name, Source). This
+%% function traverses the source table specified in Source, and feeds the
+%% data in the destination table.
+%%
+%% @spec retrieve_server(Table_Name, Session_Pid) -> true | {error, Error}
+%% @end
+%%---------------------------------------------------------------------
+replicate(Source, Destination, Key) ->
+    case Key of
+	'$end_of_table' ->
+	    true;
+	_ ->
+	    S = peak_session(Source, Key),
+	    	    global:whereis_name(Destination) ! {undefined ,add,
+	    	       lists:nth(1, S),
+	    	       lists:nth(2, S),
+	    	       lists:nth(3, S),
+		       lists:nth(4, S),
+		       lists:nth(5, S),
+		       lists:nth(6, S)},
+	    replicate(Source, Destination, ets:next(Source, Key))
+    end.