Implemented the characteristic error handling.

In case of enabling notifications and writing values to the LE device, some errors can occur and which are reported now.

Change-Id: I02c6deab925d06916c5b56705c9423386400f713
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>

8 files changed, 82 insertions, 25 deletions

diff --git a/src/bluetooth/qlowenergycharacteristicinfo.cpp b/src/bluetooth/qlowenergycharacteristicinfo.cpp
index 232d03ca..44a7b58d 100644
--- a/src/bluetooth/qlowenergycharacteristicinfo.cpp
+++ b/src/bluetooth/qlowenergycharacteristicinfo.cpp
@@ -249,9 +249,10 @@ bool QLowEnergyCharacteristicInfo::isNotificationCharacteristic() const
 }
 
 /*!
-    Writes the value \a value directly to LE device.
+    Writes the value \a value directly to LE device. If the value was not written successfully
+    an error will be emitted with an error string.
 
-    \sa setValue()
+    \sa errorString()
 */
 void QLowEnergyCharacteristicInfo::writeValue(const QByteArray &value)
 {
@@ -291,4 +292,15 @@ QList<QLowEnergyDescriptorInfo> QLowEnergyCharacteristicInfo::descriptors() cons
     return d_ptr->descriptorsList;
 }
 
+/*!
+    Returns an error string if error occurred. An error is emitted in the
+    QLowEnergyController class.
+
+    \sa QLowEnergyController::error(const QLowEnergyCharacteristicInfo &)
+*/
+QString QLowEnergyCharacteristicInfo::errorString() const
+{
+    return d_ptr->errorString;
+}
+
 QT_END_NAMESPACE
diff --git a/src/bluetooth/qlowenergycharacteristicinfo.h b/src/bluetooth/qlowenergycharacteristicinfo.h
index 0622b5d9..2e28e337 100644
--- a/src/bluetooth/qlowenergycharacteristicinfo.h
+++ b/src/bluetooth/qlowenergycharacteristicinfo.h
@@ -101,6 +101,8 @@ public:
 
     bool isValid() const;
 
+    QString errorString() const;
+
 protected:
     QSharedPointer<QLowEnergyCharacteristicInfoPrivate> d_ptr;
 
diff --git a/src/bluetooth/qlowenergycharacteristicinfo_bluez.cpp b/src/bluetooth/qlowenergycharacteristicinfo_bluez.cpp
index fa57ffc4..f66100ed 100644
--- a/src/bluetooth/qlowenergycharacteristicinfo_bluez.cpp
+++ b/src/bluetooth/qlowenergycharacteristicinfo_bluez.cpp
@@ -55,7 +55,7 @@
 QT_BEGIN_NAMESPACE
 
 QLowEnergyCharacteristicInfoPrivate::QLowEnergyCharacteristicInfoPrivate():
-    value (QByteArray()), permission(0), notification (false), handle(QStringLiteral("0x0000")), properties(QVariantMap()), characteristic(0), m_signalConnected(false)
+    value (QByteArray()), permission(0), notification (false), handle(QStringLiteral("0x0000")), properties(QVariantMap()), errorString(""), characteristic(0), m_signalConnected(false)
 {
     process = process->instance();
     t=0;
@@ -129,26 +129,31 @@ void QLowEnergyCharacteristicInfoPrivate::replyReceived(const QString &reply)
 
 void QLowEnergyCharacteristicInfoPrivate::setValue(const QByteArray &wantedValue)
 {
-    process = process->instance();
-    if (!m_signalConnected) {
-        connect(process, SIGNAL(replySend(const QString &)), this, SLOT(replyReceived(const QString &)));
-        m_signalConnected = true;
-    }
-    value = wantedValue;
-    QString command;
-    if (notification == true)
-        command = QStringLiteral("char-write-req ") + notificationHandle + QStringLiteral(" ") + QString::fromLocal8Bit(value.constData());
-    else
-        command = QStringLiteral("char-write-req ") + handle + QStringLiteral(" ") + QString::fromLocal8Bit(value.constData());
+    if (permission & QLowEnergyCharacteristicInfo::Write) {
+        process = process->instance();
+        if (!m_signalConnected) {
+            connect(process, SIGNAL(replySend(const QString &)), this, SLOT(replyReceived(const QString &)));
+            m_signalConnected = true;
+        }
+        value = wantedValue;
+        QString command;
+        if (notification == true)
+            command = QStringLiteral("char-write-req ") + notificationHandle + QStringLiteral(" ") + QString::fromLocal8Bit(value.constData());
+        else
+            command = QStringLiteral("char-write-req ") + handle + QStringLiteral(" ") + QString::fromLocal8Bit(value.constData());
 
 
-#ifdef QT_LOWENERGYCHARACTERISTIC_DEBUG
-    qDebug() << command << t << process;
-#endif
-    process->executeCommand(command);
-    process->executeCommand(QStringLiteral("\n"));
-    t++;
-
+    #ifdef QT_LOWENERGYCHARACTERISTIC_DEBUG
+        qDebug() << command << t << process;
+    #endif
+        process->executeCommand(command);
+        process->executeCommand(QStringLiteral("\n"));
+        t++;
+    }
+    else {
+        errorString = QStringLiteral("This characteristic does not support write operations.");
+        emit error(uuid);
+    }
 }
 
 bool QLowEnergyCharacteristicInfoPrivate::enableNotification()
@@ -162,6 +167,8 @@ bool QLowEnergyCharacteristicInfoPrivate::enableNotification()
 #ifdef QT_LOWENERGYCHARACTERISTIC_DEBUG
         qDebug() << "Notification changes not allowed";
 #endif
+        errorString = QStringLiteral("This characteristic does not support notifications.");
+        emit error(uuid);
         return false;
     }
     QByteArray val;
diff --git a/src/bluetooth/qlowenergycharacteristicinfo_p.h b/src/bluetooth/qlowenergycharacteristicinfo_p.h
index 379ca5d4..7a42f4a3 100644
--- a/src/bluetooth/qlowenergycharacteristicinfo_p.h
+++ b/src/bluetooth/qlowenergycharacteristicinfo_p.h
@@ -86,6 +86,7 @@ public:
     QString notificationHandle;
     int instance;
     QVariantMap properties;
+    QString errorString;
     QList<QLowEnergyDescriptorInfo> descriptorsList;
 #ifdef QT_QNX_BLUETOOTH
     bt_gatt_characteristic_t characteristic;
@@ -104,6 +105,7 @@ public Q_SLOTS:
 
 Q_SIGNALS:
     void notifyValue(const QBluetoothUuid &);
+    void error(const QBluetoothUuid &);
 
 private:
 #ifdef QT_BLUEZ_BLUETOOTH
diff --git a/src/bluetooth/qlowenergycharacteristicinfo_qnx.cpp b/src/bluetooth/qlowenergycharacteristicinfo_qnx.cpp
index b5d4bf8c..f5de6b5d 100644
--- a/src/bluetooth/qlowenergycharacteristicinfo_qnx.cpp
+++ b/src/bluetooth/qlowenergycharacteristicinfo_qnx.cpp
@@ -89,7 +89,7 @@ int stringToBuffer(const QString &stringData, uint8_t *buffer, int bufferLength)
 }
 
 QLowEnergyCharacteristicInfoPrivate::QLowEnergyCharacteristicInfoPrivate():
-    name(QString()), value(QByteArray()), permission(0), instance(-1), properties(QVariantMap()), handle(QStringLiteral("0x0000"))
+    name(QString()), value(QByteArray()), permission(0), instance(-1), handle(QStringLiteral("0x0000")), properties(QVariantMap()), errorString("")
 {
 
 }
@@ -138,18 +138,22 @@ bool QLowEnergyCharacteristicInfoPrivate::enableNotification()
 {
     if (instance == -1) {
         qBBBluetoothDebug() << " GATT service not connected ";
-        //q_ptr->error(QLowEnergyCharacteristicInfo::NotConnected);
+        errorString = QStringLiteral("Service is not connected");
+        emit error(uuid);
         return false;
     }
     if ( (permission & QLowEnergyCharacteristicInfo::Notify) == 0) {
         qBBBluetoothDebug() << "Notification changes not allowed";
+        errorString = QStringLiteral("This characteristic does not support notifications.");
+        emit error(uuid);
         return false;
     }
 
     int rc = bt_gatt_enable_notify(instance, &characteristic, 1);
     if (rc != 0) {
         qBBBluetoothDebug() << "bt_gatt_enable_notify errno=" << errno << strerror(errno);
-        //emit q_ptr->error(QLowEnergyCharacteristicInfo::NotificationFail);
+        errorString = QString::fromLatin1(strerror(errno));
+        emit error(uuid);
         return false;
     } else {
         qBBBluetoothDebug() << "bt_gatt_enable_notify was presumably OK";
@@ -164,6 +168,8 @@ void QLowEnergyCharacteristicInfoPrivate::setValue(const QByteArray &wantedValue
         uint8_t *characteristicBuffer = (uint8_t *)alloca(characteristicLen / 2 + 1);
         if (!characteristicBuffer) {
             qBBBluetoothDebug() << "GATT characteristic: Not enough memory";
+            errorString = QStringLiteral("Not enough memory.");
+            emit error(uuid);
             bt_gatt_disconnect_instance(instance);
             return;
         }
@@ -176,9 +182,15 @@ void QLowEnergyCharacteristicInfoPrivate::setValue(const QByteArray &wantedValue
 
             if (byteCount < 0) {
                 qBBBluetoothDebug() << "Unable to write characteristic value: " << errno << strerror(errno);
+                errorString = QStringLiteral("Unable to write characteristic value: ") + QString::fromLatin1(strerror(errno));
+                emit error(uuid);
             }
         }
     }
+    else {
+        errorString = QStringLiteral("Characteristic does not allow write operations. The wanted value was not written to the device.");
+        emit error(uuid);
+    }
     value = wantedValue;
     properties[QStringLiteral("value")] = value;
     emit notifyValue(uuid);
diff --git a/src/bluetooth/qlowenergycontroller.cpp b/src/bluetooth/qlowenergycontroller.cpp
index c74a67b2..eef5c81a 100644
--- a/src/bluetooth/qlowenergycontroller.cpp
+++ b/src/bluetooth/qlowenergycontroller.cpp
@@ -81,12 +81,20 @@ QT_BEGIN_NAMESPACE
 /*!
     \fn void QLowEnergyController::error(const QLowEnergyServiceInfo &)
 
-    This signal is emitted when an error occurs.
+    This signal is emitted when the service error occurs.
 
     \sa QLowEnergyServiceInfo::errorString()
 */
 
 /*!
+    \fn void QLowEnergyController::error(const QLowEnergyCharacteristicInfo &)
+
+    This signal is emitted when the characteristic error occurs.
+
+    \sa QLowEnergyCharacteristicInfo::errorString()
+*/
+
+/*!
     \fn void QLowEnergyController::disconnected(const QLowEnergyServiceInfo &)
 
     Emits disconnected signal with disconnected LE service.
@@ -129,6 +137,17 @@ void QLowEnergyControllerPrivate::_q_serviceError(const QBluetoothUuid &uuid)
     }
 }
 
+void QLowEnergyControllerPrivate::_q_characteristicError(const QBluetoothUuid &uuid)
+{
+    for (int i = 0; i < m_leServices.size(); i++) {
+        QList<QLowEnergyCharacteristicInfo> characteristics = m_leServices.at(i).characteristics();
+        for (int j = 0; j < characteristics.size(); j++) {
+            if (characteristics.at(j).uuid() == uuid)
+                emit q_ptr->error(characteristics.at(j));
+        }
+    }
+}
+
 
 void QLowEnergyControllerPrivate::_q_valueReceived(const QBluetoothUuid &uuid)
 {
diff --git a/src/bluetooth/qlowenergycontroller.h b/src/bluetooth/qlowenergycontroller.h
index 4f49acb5..432e6669 100644
--- a/src/bluetooth/qlowenergycontroller.h
+++ b/src/bluetooth/qlowenergycontroller.h
@@ -69,6 +69,7 @@ public:
 Q_SIGNALS:
     void connected(const QLowEnergyServiceInfo &);
     void error(const QLowEnergyServiceInfo &);
+    void error(const QLowEnergyCharacteristicInfo &);
     void disconnected(const QLowEnergyServiceInfo &);
     void valueChanged(const QLowEnergyCharacteristicInfo &);
 
@@ -79,6 +80,7 @@ private:
 
     Q_PRIVATE_SLOT(d_func(), void _q_serviceConnected(const QBluetoothUuid &uuid))
     Q_PRIVATE_SLOT(d_func(), void _q_serviceError(const QBluetoothUuid &uuid))
+    Q_PRIVATE_SLOT(d_func(), void _q_characteristicError(const QBluetoothUuid &uuid))
     Q_PRIVATE_SLOT(d_func(), void _q_valueReceived(const QBluetoothUuid &uuid))
     Q_PRIVATE_SLOT(d_func(), void _q_serviceDisconnected(const QBluetoothUuid &uuid))
 };
diff --git a/src/bluetooth/qlowenergycontroller_p.h b/src/bluetooth/qlowenergycontroller_p.h
index 96ec3730..b19f7024 100644
--- a/src/bluetooth/qlowenergycontroller_p.h
+++ b/src/bluetooth/qlowenergycontroller_p.h
@@ -56,6 +56,7 @@ public:
 
     void _q_serviceConnected(const QBluetoothUuid &uuid);
     void _q_serviceError(const QBluetoothUuid &uuid);
+    void _q_characteristicError(const QBluetoothUuid &uuid);
     void _q_valueReceived(const QBluetoothUuid &uuid);
     void _q_serviceDisconnected(const QBluetoothUuid &uuid);