cleanup pass on reader implementation

Author: bjouhier

lib/oracle.js

@@ -44,8 +44,8 @@ function Reader(handle) {
   this._rows = [];
 }
 
-Reader.prototype.nextRows = function(cb, count) {
-  this._handle.nextRows(cb, count);
+Reader.prototype.nextRows = function() {
+  this._handle.nextRows.apply(this._handle, arguments);
 }
 
 Reader.prototype.nextRow = function(cb) {

src/reader.cpp

@@ -48,6 +48,10 @@ uni::CallbackType Reader::NextRows(const uni::FunctionCallbackInfo& args) {
     Local<String> message = String::New(baton->error->c_str());
     UNI_THROW(Exception::Error(message));
   }
+  if (baton->busy) {
+    UNI_THROW(Exception::Error(String::New("invalid state: reader is busy with another nextRows call")));
+  }
+  baton->busy = true;
 
   if (args.Length() > 1) {
     REQ_INT_ARG(0, count);
@@ -75,66 +79,53 @@ void Reader::EIO_NextRows(uv_work_t* req) {
   baton->rows = new vector<row_t*>();
   if (baton->done) return;
 
-  try {
-    if(! baton->connection->getConnection()) {
-      baton->error = new std::string("Connection already closed");
-      return;
-    }
-    if (!baton->rs) {
+  if (!baton->connection->getConnection()) {
+    baton->error = new std::string("Connection already closed");
+    return;
+  }
+  if (!baton->rs) {
+    try {
       baton->stmt = baton->connection->getConnection()->createStatement(baton->sql);
       baton->stmt->setAutoCommit(baton->connection->getAutoCommit());
       baton->stmt->setPrefetchRowCount(baton->count);
       Connection::SetValuesOnStatement(baton->stmt, baton);
-      if (baton->error) goto cleanup;
+      if (baton->error) return;
 
       int status = baton->stmt->execute();
-      if(status != oracle::occi::Statement::RESULT_SET_AVAILABLE) {
+      if (status != oracle::occi::Statement::RESULT_SET_AVAILABLE) {
          baton->error = new std::string("Connection already closed");
         return;
       }     
       baton->rs = baton->stmt->getResultSet();
-      Connection::CreateColumnsFromResultSet(baton->rs, baton, baton->columns);
-      if (baton->error) goto cleanup;
-    }
-
-    for (int i = 0; i < baton->count && baton->rs->next(); i++) {
-      row_t* row = Connection::CreateRowFromCurrentResultSetRow(baton->rs, baton, baton->columns);
-      if (baton->error) goto cleanup;
-      baton->rows->push_back(row);
+    } catch (oracle::occi::SQLException &ex) {
+      baton->error = new string(ex.getMessage());
+      return;
     }
-    if (baton->rows->size() < (size_t)baton->count) baton->done = true;
-  } catch(oracle::occi::SQLException &ex) {
-    baton->error = new string(ex.getMessage());
-  } catch (const exception& ex) {
-    baton->error = new string(ex.what());
-  } catch (...) {
-    baton->error = new string("Unknown Error");
+    Connection::CreateColumnsFromResultSet(baton->rs, baton, baton->columns);
+    if (baton->error) return;
   }
-cleanup:
-  // nothing for now, cleanup happens in destructor
-  ;
+  for (int i = 0; i < baton->count && baton->rs->next(); i++) {
+    row_t* row = Connection::CreateRowFromCurrentResultSetRow(baton->rs, baton, baton->columns);
+    if (baton->error) return;
+    baton->rows->push_back(row);
+  }
+  if (baton->rows->size() < (size_t)baton->count) baton->done = true;
 }
 
 void Reader::EIO_AfterNextRows(uv_work_t* req, int status) {
   UNI_SCOPE(scope);
   ReaderBaton* baton = static_cast<ReaderBaton*>(req->data);
 
+  baton->busy = false;
   baton->connection->Unref();
   // transfer callback to local and dispose persistent handle
   // must be done before invoking callback because callback may set another callback into baton->callback
   Local<Function> cb = uni::Deref(baton->callback);
   baton->callback.Dispose();
 
-  try {
-    Handle<Value> argv[2];
-    Connection::handleResult(baton, argv);
-    node::MakeCallback(Context::GetCurrent()->Global(), cb, 2, argv);
-  } catch(const exception &ex) {
-    Handle<Value> argv[2];
-    argv[0] = Exception::Error(String::New(ex.what()));
-    argv[1] = Undefined();
-    node::MakeCallback(Context::GetCurrent()->Global(), cb, 2, argv);
-  }
+  Handle<Value> argv[2];
+  Connection::handleResult(baton, argv);
+  node::MakeCallback(Context::GetCurrent()->Global(), cb, 2, argv);
 
   baton->ResetRows();
   if (baton->done || baton->error) {

src/readerBaton.h

@@ -11,6 +11,7 @@ class ReaderBaton : public ExecuteBaton {
     stmt = NULL;
     rs = NULL;
     done = false;
+    busy = false;
   }
   ~ReaderBaton() {
     ResetStatement();
@@ -33,6 +34,7 @@ class ReaderBaton : public ExecuteBaton {
   oracle::occi::ResultSet* rs;
   int count;
   bool done;
+  bool busy;
 };
 
 #endif