QtNetwork: remove double buffering on sockets

Removes the readBuffer from the QAbstractSocket since data is already
buffered in the QIODevice.

Change-Id: I4e50b791fd2852455e526fa2c07089d4d3f0b2a4
Reviewed-by: Prasanth Ullattil <prasanth.ullattil@nokia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

2 files changed, 14 insertions, 20 deletions

diff --git a/src/network/ssl/qsslsocket.cpp b/src/network/ssl/qsslsocket.cpp
index 2dee60408b..b2547487ba 100644
--- a/src/network/ssl/qsslsocket.cpp
+++ b/src/network/ssl/qsslsocket.cpp
@@ -707,7 +707,7 @@ qint64 QSslSocket::bytesAvailable() const
     Q_D(const QSslSocket);
     if (d->mode == UnencryptedMode)
         return QIODevice::bytesAvailable() + (d->plainSocket ? d->plainSocket->bytesAvailable() : 0);
-    return QIODevice::bytesAvailable() + d->readBuffer.size();
+    return QIODevice::bytesAvailable();
 }
 
 /*!
@@ -764,7 +764,7 @@ bool QSslSocket::canReadLine() const
     Q_D(const QSslSocket);
     if (d->mode == UnencryptedMode)
         return QIODevice::canReadLine() || (d->plainSocket && d->plainSocket->canReadLine());
-    return QIODevice::canReadLine() || (!d->readBuffer.isEmpty() && d->readBuffer.canReadLine());
+    return QIODevice::canReadLine();
 }
 
 /*!
@@ -781,12 +781,8 @@ void QSslSocket::close()
     QTcpSocket::close();
 
     // must be cleared, reading/writing not possible on closed socket:
-    d->readBuffer.clear();
+    d->buffer.clear();
     d->writeBuffer.clear();
-    // for QTcpSocket this is already done because it uses the readBuffer/writeBuffer
-    // if the QIODevice it is based on
-    // ### FIXME QSslSocket should probably do similar instead of having
-    // its own readBuffer/writeBuffer
 }
 
 /*!
@@ -797,7 +793,7 @@ bool QSslSocket::atEnd() const
     Q_D(const QSslSocket);
     if (d->mode == UnencryptedMode)
         return QIODevice::atEnd() && (!d->plainSocket || d->plainSocket->atEnd());
-    return QIODevice::atEnd() && d->readBuffer.isEmpty();
+    return QIODevice::atEnd();
 }
 
 /*!
@@ -1829,21 +1825,18 @@ qint64 QSslSocket::readData(char *data, qint64 maxlen)
     if (d->mode == UnencryptedMode && !d->autoStartHandshake) {
         readBytes = d->plainSocket->read(data, maxlen);
     } else {
-        do {
-            const char *readPtr = d->readBuffer.readPointer();
-            int bytesToRead = qMin<int>(maxlen - readBytes, d->readBuffer.nextDataBlockSize());
-            ::memcpy(data + readBytes, readPtr, bytesToRead);
-            readBytes += bytesToRead;
-            d->readBuffer.free(bytesToRead);
-        } while (!d->readBuffer.isEmpty() && readBytes < maxlen);
+        int bytesToRead = qMin<int>(maxlen, d->buffer.size());
+        readBytes = d->buffer.read(data, bytesToRead);
     }
+
 #ifdef QSSLSOCKET_DEBUG
     qDebug() << "QSslSocket::readData(" << (void *)data << ',' << maxlen << ") ==" << readBytes;
 #endif
 
     // possibly trigger another transmit() to decrypt more data from the socket
-    if (d->readBuffer.isEmpty() && d->plainSocket->bytesAvailable())
+    if (d->buffer.isEmpty() && d->plainSocket->bytesAvailable()) {
         QMetaObject::invokeMethod(this, "_q_flushReadBuffer", Qt::QueuedConnection);
+    }
 
     return readBytes;
 }
@@ -1907,7 +1900,7 @@ void QSslSocketPrivate::init()
     // that it is possible setting it before connecting
 //    ignoreErrorsList.clear();
 
-    readBuffer.clear();
+    buffer.clear();
     writeBuffer.clear();
     configuration.peerCertificate.clear();
     configuration.peerCertificateChain.clear();
@@ -2112,7 +2105,7 @@ void QSslSocketPrivate::createPlainSocket(QIODevice::OpenMode openMode)
                q, SIGNAL(proxyAuthenticationRequired(QNetworkProxy,QAuthenticator*)));
 #endif
 
-    readBuffer.clear();
+    buffer.clear();
     writeBuffer.clear();
     connectionEncrypted = false;
     configuration.peerCertificate.clear();
diff --git a/src/network/ssl/qsslsocket_openssl.cpp b/src/network/ssl/qsslsocket_openssl.cpp
index 38368583ff..83071f2c7a 100644
--- a/src/network/ssl/qsslsocket_openssl.cpp
+++ b/src/network/ssl/qsslsocket_openssl.cpp
@@ -953,12 +953,13 @@ void QSslSocketBackendPrivate::transmit()
         }
 
         // Check if we've got any data to be read from the socket.
-        if (!connectionEncrypted || !readBufferMaxSize || readBuffer.size() < readBufferMaxSize)
+        if (!connectionEncrypted || !readBufferMaxSize || buffer.size() < readBufferMaxSize)
             while ((pendingBytes = plainSocket->bytesAvailable()) > 0) {
                 // Read encrypted data from the socket into a buffer.
                 data.resize(pendingBytes);
                 // just peek() here because q_BIO_write could write less data than expected
                 int encryptedBytesRead = plainSocket->peek(data.data(), pendingBytes);
+
 #ifdef QSSLSOCKET_DEBUG
                 qDebug() << "QSslSocketBackendPrivate::transmit: read" << encryptedBytesRead << "encrypted bytes from the socket";
 #endif
@@ -1025,7 +1026,7 @@ void QSslSocketBackendPrivate::transmit()
 #ifdef QSSLSOCKET_DEBUG
                 qDebug() << "QSslSocketBackendPrivate::transmit: decrypted" << readBytes << "bytes";
 #endif
-                char *ptr = readBuffer.reserve(readBytes);
+                char *ptr = buffer.reserve(readBytes);
                 ::memcpy(ptr, data.data(), readBytes);
 
                 if (readyReadEmittedPointer)