From e4878b20647e2229661bdd2d19465870bab27ba9 Mon Sep 17 00:00:00 2001
From: Tee Teoh <tteoh@tee-teohs-macbook.local>
Date: Wed, 18 Jun 2008 23:34:09 -0400
Subject: [PATCH] Makefile changes for better compiles. sqlite.erl supports
 start_link/stop and open/close paradigm. added write_sql creation.

---
 priv/Makefile  |  6 ++--
 src/sqlite.erl | 81 +++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 70 insertions(+), 17 deletions(-)

diff --git a/priv/Makefile b/priv/Makefile
index 4ec8355..e3a3ec0 100644
--- a/priv/Makefile
+++ b/priv/Makefile
@@ -4,11 +4,11 @@ FLAGS=-I$(OTP_DIR)/include -L$(OTP_DIR)/lib
 #GCC=/opt/local/bin/gcc-apple-4.2 
 GCC=/usr/bin/gcc
 
-all: erl_comm.c sqlite_port.c
-	$(GCC) -Wall -o sqlite_port erl_comm.c sqlite_port.c $(FLAGS) $(LIB)
+all: obj
+	$(GCC) -Wall -o sqlite_port $(FLAGS) $(LIB) erl_comm.o sqlite_port.o
 
 obj: erl_comm.c sqlite_port.c
-	$(GCC) -Wall -c $(FLAGS) erl_comm.c sqlite_port.c
+	$(GCC) -Wall -c $(FLAGS) erl_comm.c sqlite_port.c 
 
 clean:
 	- rm -f *.o sqlite_port
diff --git a/src/sqlite.erl b/src/sqlite.erl
index a3731ee..64ae3b5 100644
--- a/src/sqlite.erl
+++ b/src/sqlite.erl
@@ -12,12 +12,14 @@
 %% API
 -export([open/1, open/2]).
 -export([start_link/1, start_link/2]).
--export([stop/1, close/1]).
--export([sql_exec/2]).
+-export([stop/0, close/1]).
+-export([sql_exec/1, sql_exec/2]).
 
--export([create_table/3]).
--export([list_tables/1, table_info/2]).
--export([create_table_sql/2]).
+-export([create_table/2, create_table/3]).
+-export([list_tables/0, list_tables/1, table_info/1, table_info/2]).
+-export([write/2, write/3]).
+
+-export([write_sql/2, write_col_sql/1, write_value_sql/1]).
 
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -33,7 +35,7 @@
 %% Description: Starts the server
 %%--------------------------------------------------------------------
 start_link(Db) ->
-    start_link(Db, [{db, "./" ++ atom_to_list(Db) ++ ".db"}]).
+    ?MODULE:open(?MODULE, [{db, "./" ++ atom_to_list(Db) ++ ".db"}]).
 
 %%--------------------------------------------------------------------
 %% Function: start_link(Db, Options) -> {ok,Pid} | ignore | {error,Error}
@@ -41,33 +43,56 @@ start_link(Db) ->
 %%               {db, DbFile :: String()}
 %%--------------------------------------------------------------------
 start_link(Db, Options) ->
-    gen_server:start_link({local, Db}, ?MODULE, Options, []).
+    Opts = case proplists:get_value(db, Options) of
+	       undefined -> [{db, "./" ++ atom_to_list(Db) ++ ".db"} | Options];
+	       _ -> Options
+	   end,
+    ?MODULE:open(?MODULE, Opts).
 
 open(Db) ->
-    ?MODULE:start_link(Db).
+    ?MODULE:open(Db, [{db, "./" ++ atom_to_list(Db) ++ ".db"}]).
 
 open(Db, Options) ->
-    ?MODULE:start_link(Db, Options).
+    gen_server:start_link({local, Db}, ?MODULE, Options, []).
+
 
 close(Db) ->
     gen_server:call(Db, close).
 
-stop(Db) ->
-    ?MODULE:close(Db).
+stop() ->
+    ?MODULE:close(?MODULE).
     
+sql_exec(SQL) ->
+    ?MODULE:sql_exec(?MODULE, SQL).
+
 sql_exec(Db, SQL) ->
     gen_server:call(Db, {sql_exec, SQL}).
 
+create_table(Tbl, Options) ->
+    ?MODULE:create_table(?MODULE, Tbl, Options).
+
 create_table(Db, Tbl, Options) ->
     gen_server:call(Db, {create_table, Tbl, Options}).
 
 % returns list or ok
+list_tables() ->
+    ?MODULE:list_tables(?MODULE).
+
 list_tables(Db) ->
     gen_server:call(Db, list_tables).
 
+table_info(Tbl) ->
+    ?MODULE:table_info(?MODULE, Tbl).
+
 table_info(Db, Tbl) ->
     gen_server:call(Db, {table_info, Tbl}).
 
+write(Tbl, Data) ->
+    ?MODULE:write(?MODULE, Tbl, Data).
+
+write(Db, Tbl, Data) ->
+    gen_server:call(Db, {write, Tbl, Data}).
+
 %%====================================================================
 %% gen_server callbacks
 %%====================================================================
@@ -103,10 +128,10 @@ handle_call(list_tables, _From, #state{port = Port} = State) ->
     Reply = exec(Port, {list_tables, none}),
     {reply, Reply, State};
 handle_call({table_info, Tbl}, _From, #state{port = Port} = State) ->
-    % make sure we only get table info
+    % make sure we only get table info.
+    % SQL Injection warning
     SQL = io_lib:format("select sql from sqlite_master where tbl_name = '~p' and type='table';", [Tbl]),
-    Cmd = {sql_exec, SQL},
-    [{Info}] = exec(Port, Cmd),
+    [{Info}] = exec(Port, {sql_exec, SQL}),
     Reply = parse_table_info(Info),
     {reply, Reply, State};
 handle_call({create_table, Tbl, Options}, _From, #state{port = Port} = State) ->
@@ -114,6 +139,10 @@ handle_call({create_table, Tbl, Options}, _From, #state{port = Port} = State) ->
     Cmd = {sql_exec, SQL},
     Reply = exec(Port, Cmd),
     {reply, Reply, State};
+handle_call({write, Tbl, Data}, _From, #state{port = Port} = State) ->
+    % insert into t1 (data,num) values ('This is sample data',3);
+    Reply = ok,
+    {reply, Reply, State};
 handle_call(_Request, _From, State) ->
     Reply = ok,
     {reply, Reply, State}.
@@ -200,6 +229,30 @@ create_table_sql(Tbl, [{Name, Type} | Tl]) ->
 			      io_lib:format("~p ~s", [Name0, col_type(Type0)])
 		      end, Tl), ", ") ++ ");",
     lists:flatten(CT ++ Start ++ End).
+
+% insert into t1 (data,num) values ('This is sample data',3);
+write_sql(Tbl, Data) ->
+    {Cols, Values} = lists:unzip(Data),
+    lists:flatten(io_lib:format("INSERT INTO ~p (~s) values (~s);", 
+				[Tbl, write_col_sql(Cols), write_value_sql(Values)])).
+
+% currently only support integer, double/float and strings
+write_value_sql(Values) ->
+    StrValues = lists:map(fun(X) when is_integer(X) ->
+				  integer_to_list(X);
+			     (X) when is_float(X) ->
+				  float_to_list(X);
+			     (X) ->
+				  io_lib:format("'~s'", [X])
+			  end, Values),
+    string:join(StrValues, ",").
+
+write_col_sql(Cols) ->
+    StrCols = lists:map(fun(X) ->
+				atom_to_list(X)
+			end, Cols),
+    string:join(StrCols, ",").
+
      
 col_type("INTEGER") ->
     integer;