Add get changes

c_src/sqlite3_drv.c

@@ -307,12 +307,12 @@ static void stop(ErlDrvData handle) {
     }
     driver_free(drv->prepared_stmts);
   }
-  
+
   close_result = sqlite3_close(drv->db);
   if (close_result != SQLITE_OK) {
     LOG_ERROR("Failed to close DB %s, some resources aren't finalized!", drv->db_name);
   }
-  
+
   if (drv->log && (drv->log != stderr)) {
     fclose(drv->log);
   }
@@ -363,6 +363,9 @@ static ErlDrvSSizeT control(
     case CMD_ENABLE_LOAD_EXTENSION:
       enable_load_extension(drv, buf, (int) len);
       break;
+    case CMD_CHANGES:
+      changes(drv, buf, (int) len);
+      break;
     default:
       unknown(drv, buf, (int) len);
     }
@@ -370,6 +373,26 @@ static ErlDrvSSizeT control(
   return 0;
 }
 
+static int changes(sqlite3_drv_t *drv, char *buf, int len) {
+    int changes = sqlite3_changes(drv->db);
+    ErlDrvTermData spec[6];
+
+    spec[0] = ERL_DRV_PORT;
+    spec[1] = driver_mk_port(drv->port);
+    spec[2] = ERL_DRV_UINT;
+    spec[3] = changes;
+    spec[4] = ERL_DRV_TUPLE;
+    spec[5] = 2;
+
+    return
+    #ifdef PRE_R16B
+    driver_output_term(drv->port,
+    #else
+    erl_drv_output_term(spec[1],
+    #endif
+    spec, sizeof(spec) / sizeof(spec[0]));
+}
+
 static int enable_load_extension(sqlite3_drv_t* drv, char *buf, int len) {
 #ifdef ERLANG_SQLITE3_LOAD_EXTENSION
   char enable = buf[0];
@@ -433,7 +456,7 @@ static inline void exec_async_command(
   } else {
     async_invoke(async_command);
     ready_async((ErlDrvData) drv, (ErlDrvThreadData) async_command);
-  }  
+  }
 }
 
 static inline int sql_exec_statement(

c_src/sqlite3_drv.h

@@ -49,6 +49,7 @@ typedef int ErlDrvSSizeT;
 #define CMD_PREPARED_COLUMNS 11
 #define CMD_SQL_EXEC_SCRIPT 12
 #define CMD_ENABLE_LOAD_EXTENSION 13
+#define CMD_CHANGES 14
 
 typedef struct ptr_list {
   void *head;
@@ -118,6 +119,7 @@ static void sql_free_async(void *async_command);
 static void ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data);
 static int unknown(sqlite3_drv_t *bdb_drv, char *buf, int len);
 static int enable_load_extension(sqlite3_drv_t *drv, char *buf, int len);
+static int changes(sqlite3_drv_t *drv, char *buf, int len);
 
 #if defined(_MSC_VER)
 #pragma warning(default: 4201)

src/sqlite3.erl

@@ -40,6 +40,7 @@
 -export([delete/2, delete/3, delete_timeout/4]).
 -export([drop_table/1, drop_table/2, drop_table_timeout/3]).
 -export([vacuum/0, vacuum/1, vacuum_timeout/2]).
+-export([changes/1]).
 
 %% -export([create_function/3]).
 
@@ -164,6 +165,18 @@ stop() ->
 enable_load_extension(Db, Value) ->
     gen_server:call(Db, {enable_load_extension, Value}).
 
+%%--------------------------------------------------------------------
+%% @doc
+%%   Get affected rows.
+%% @end
+%%--------------------------------------------------------------------
+
+changes(Db) ->
+    gen_server:call(Db, changes).
+
+changes(Db, Timeout) ->
+    gen_server:call(Db, changes, Timeout).
+
 %%--------------------------------------------------------------------
 %% @doc
 %%   Executes the Sql statement directly.
@@ -974,6 +987,9 @@ handle_call({enable_load_extension, _Value} = Payload, _From, State = #state{por
         Port, refs = _Refs}) ->
     Reply = exec(Port, Payload),
     {reply, Reply, State};
+handle_call(changes = Payload, _From, State = #state{port = Port, refs = _Refs}) ->
+    Reply = exec(Port, Payload),
+    {reply, Reply, State};
 handle_call({Cmd, Ref}, _From, State = #state{port = Port, refs = Refs}) ->
     Reply = case dict:find(Ref, Refs) of
                 {ok, Index} ->
@@ -1033,7 +1049,7 @@ terminate(_Reason, #state{port = Port}) ->
         {error, permanent} ->
             %% Older Erlang versions mark any driver using driver_async
             %% as permanent
-            ok; 
+            ok;
         {error, ErrorDesc} ->
             error_logger:error_msg("Error unloading sqlite3 driver: ~s~n",
                                    [erl_ddll:format_error(ErrorDesc)])
@@ -1074,6 +1090,7 @@ get_priv_dir() ->
 -define(PREPARED_COLUMNS, 11).
 -define(SQL_EXEC_SCRIPT, 12).
 -define(ENABLE_LOAD_EXTENSION, 13).
+-define(CHANGES, 14).
 
 create_port_cmd(DbFile) ->
     atom_to_list(?DRIVER_NAME) ++ " " ++ DbFile.
@@ -1126,6 +1143,9 @@ exec(Port, {enable_load_extension, Value}) ->
     end,
     port_control(Port, ?ENABLE_LOAD_EXTENSION, <<Payload>>),
     wait_result(Port);
+exec(Port, changes) ->
+    port_control(Port, ?CHANGES, <<"">>),
+    wait_result(Port);
 exec(Port, {Cmd, Index}) when is_integer(Index) ->
     CmdCode = case Cmd of
                   next -> ?PREPARED_STEP;

test.erl

@@ -8,9 +8,11 @@ test() ->
     sqlite3:open(ct),
     sqlite3:create_table(ct, user, [{id, integer, [primary_key]}, {name, text}, {age, integer}, {wage, integer}]),
     [user] = sqlite3:list_tables(ct),
+    0 = sqlite3:changes(ct),
     [{id, integer, [primary_key]}, {name, text}, {age, integer}, {wage, integer}] = sqlite3:table_info(ct, user),
     {rowid, Id1} = sqlite3:write(ct, user, [{name, "abby"}, {age, 20}, {wage, 2000}]),
     Id1 = 1,
+    1 = sqlite3:changes(ct),
     {rowid, Id2} = sqlite3:write(ct, user, [{name, "marge"}, {age, 30}, {wage, 2000}]),
     Id2 = 2,
     [{columns, Columns}, {rows, Rows1}] = sqlite3:sql_exec(ct, "select * from user;"),

test/sqlite3_test.erl

@@ -53,7 +53,8 @@ all_test_() ->
       ?FuncTest(large_offset),
       ?FuncTest(issue23),
       ?FuncTest(issue13),
-      ?FuncTest(enable_load_extension)]}.
+      ?FuncTest(enable_load_extension),
+      ?FuncTest(changes)]}.
 
 anonymous_test() ->
     {ok, Pid} = sqlite3:open(anonymous, []),
@@ -349,6 +350,20 @@ issue13() ->
 enable_load_extension() ->
     ?assertEqual(ok, sqlite3:enable_load_extension(ct, 1)).
 
+changes() ->
+    sqlite3:open(changes, [in_memory]),
+    sqlite3:sql_exec(changes, "CREATE TABLE person(id INTEGER);"),
+    ?assertEqual(0, sqlite3:changes(changes)),
+    {rowid, _} = sqlite3:sql_exec(changes, "INSERT INTO person (id) VALUES (1)"),
+    {rowid, _} = sqlite3:sql_exec(changes, "INSERT INTO person (id) VALUES (2)"),
+    {rowid, _} = sqlite3:sql_exec(changes, "INSERT INTO person (id) VALUES (3)"),
+    {rowid, _} = sqlite3:sql_exec(changes, "INSERT INTO person (id) VALUES (4)"),
+    {rowid, _} = sqlite3:sql_exec(changes, "INSERT INTO person (id) VALUES (5)"),
+    ?assertEqual(1, sqlite3:changes(changes)),
+    ok = sqlite3:sql_exec(changes, "UPDATE person SET id = 10"),
+    ?assertEqual(5, sqlite3:changes(changes)),
+    sqlite3:close(changes).
+
 issue23() ->
     sqlite3:open(issue23, [in_memory]),
     ok = sqlite3:create_table(issue23, issue23, [{issue23, integer}]),
@@ -362,7 +377,7 @@ non_db_file_test() ->
     process_flag(trap_exit, true),
     ?assertMatch({error, _},
         sqlite3:start_link(bad_file, [{file, "/"}])),
-    receive 
+    receive
         {'EXIT', _, _} -> ok;
         _ -> ?assert(false)
     end.