Merge pull request sql-js#283 from ShapovalovKL/master

fix function pointer leak

Author: lovasoa

src/api.coffee

@@ -244,6 +244,7 @@ class Database
         @db = getValue(apiTemp, 'i32')
         RegisterExtensionFunctions(@db)
         @statements = {} # A list of all prepared statements of the database
+        @functions = {} # A list of all user function of the database (created by create_function call)
 
     ### Execute an SQL query, ignoring the rows it returns.
 
@@ -395,6 +396,8 @@ class Database
     ###
     'export': ->
         stmt['free']() for _,stmt of @statements
+        removeFunction(func) for _,func of @functions
+        @functions={}
         @handleError sqlite3_close_v2 @db
         binaryDb = FS.readFile @filename, encoding:'binary'
         @handleError sqlite3_open @filename, apiTemp
@@ -414,6 +417,8 @@ class Database
     ###
     'close': ->
         stmt['free']() for _,stmt of @statements
+        removeFunction(func) for _,func of @functions
+        @functions={}
         @handleError sqlite3_close_v2 @db
         FS.unlink '/' + @filename
         @db = null
@@ -478,8 +483,11 @@ class Database
                 switch typeof(result)
                     when 'number' then sqlite3_result_double(cx, result)
                     when 'string' then sqlite3_result_text(cx, result, -1, -1)
-
+        if(name of @functions)
+          removeFunction(@functions[name])
+          delete @functions[name]
         # Generate a pointer to the wrapped, user defined function, and register with SQLite.
         func_ptr = addFunction(wrapped_func)
+        @functions[name]=func_ptr
         @handleError sqlite3_create_function_v2 @db, name, func.length, SQLite.UTF8, 0, func_ptr, 0, 0, 0
         return @

test/test_functions_recreate.js

@@ -0,0 +1,71 @@
+exports.test = function(sql, assert) {
+  // Test 1: Create a database, Register single function, close database, repeat 1000 times
+  
+  for (var i = 1; i <= 1000; i++) 
+  {
+    let lastStep=(i==1000);
+    let db = new sql.Database();
+    function add() {return i;}
+    try
+    {
+      db.create_function("TestFunction"+i, add)
+    }catch(e)
+    {
+      assert.ok(false,"Test 1: Recreate database "+i+"th times and register function failed with exception:"+e);
+      db.close();
+      break;
+    }
+    var result = db.exec("SELECT TestFunction"+i+"()");
+    var result_str = result[0]["values"][0][0];
+    if((result_str!=i)||lastStep)
+    {
+      assert.equal(result_str, i, "Test 1: Recreate database "+i+"th times and register function");
+      db.close();
+      break;
+    }
+    db.close();
+  }
+  
+  // Test 2: Create a database, Register same function  1000 times, close database
+  {
+    let db = new sql.Database();
+    for (var i = 1; i <= 1000; i++) 
+    {
+      let lastStep=(i==1000);
+      function add() {return i;}
+      try
+      {
+        db.create_function("TestFunction", add);
+      }catch(e)
+      {
+        assert.ok(false,"Test 2: Reregister function "+i+"th times failed with exception:"+e);
+        break;
+      }
+      var result = db.exec("SELECT TestFunction()");
+      var result_str = result[0]["values"][0][0];
+      if((result_str!=i)||lastStep)
+      {
+        assert.equal(result_str, i, "Test 2: Reregister function "+i+"th times");
+        break;
+      }
+    }
+    db.close();
+  }
+};
+
+
+if (module == require.main) {
+	const target_file = process.argv[2];
+  const sql_loader = require('./load_sql_lib');
+  sql_loader(target_file).then((sql)=>{
+    require('test').run({
+      'test creating multiple functions': function(assert){
+        exports.test(sql, assert);
+      }
+    });
+  })
+  .catch((e)=>{
+    console.error(e);
+    assert.fail(e);
+  });
+}