Use lastError to report relevant errors

This improves the error handling situation
in the module.

Change-Id: I9a67038efd3d82d7a2b87c2184cce52ad5b855e7
Task-number: QTEE-1037
Reviewed-by: Teemu Holappa <teemu.holappa@theqtcompany.com>

4 files changed, 87 insertions, 52 deletions

diff --git a/src/wifi/qwificontroller.cpp b/src/wifi/qwificontroller.cpp
index 61f5761..a260050 100644
--- a/src/wifi/qwificontroller.cpp
+++ b/src/wifi/qwificontroller.cpp
@@ -86,7 +86,7 @@ QWifiController::QWifiController(QWifiManager *manager, QWifiManagerPrivate *man
     m_exitEventThread(false),
     m_interface(QWifiDevice::wifiInterfaceName()),
     m_eventThread(new QWifiEventThread(this)),
-    m_supplicant(new QWifiSupplicant(this))
+    m_supplicant(new QWifiSupplicant(this, m_managerPrivate))
 {
     qRegisterMetaType<QWifiManager::BackendState>("QWifiManager::BackendState");
 }
@@ -138,40 +138,39 @@ void QWifiController::initializeBackend()
 {
     qCDebug(B2QT_WIFI) << "initializing wifi backend";
     emit backendStateChanged(QWifiManager::Initializing);
-    qCDebug(B2QT_WIFI) << "run ifconfig (up)";
+
     QProcess ifconfig;
-    ifconfig.start(QStringLiteral("ifconfig"), QStringList() << QLatin1String(m_interface) << QStringLiteral("up"));
+    ifconfig.start(QStringLiteral("ifconfig"),
+                   QStringList() << QLatin1String(m_interface) << QStringLiteral("up"));
+    if (!ifconfig.waitForStarted()) {
+        m_managerPrivate->updateLastError(ifconfig.program() + QLatin1String(": ") + ifconfig.errorString());
+        return;
+    }
+
     ifconfig.waitForFinished();
     bool initFailed = false;
-    if (ifconfig.exitStatus() != QProcess::NormalExit && ifconfig.exitCode() != 0) {
-        qCWarning(B2QT_WIFI) << "failed to bring up wifi interface!";
+    QByteArray error = ifconfig.readAllStandardError();
+    if (!error.isEmpty()) {
+        m_managerPrivate->updateLastError(QLatin1String("failed to bring up wifi interface: " + error));
         initFailed = true;
     }
-    if (!initFailed && resetSupplicantSocket()) {
-        qCDebug(B2QT_WIFI) << "wifi backend started successfully";
+    if (!initFailed && resetSupplicantSocket())
         emit backendStateChanged(QWifiManager::Running);
-    } else {
+    else
         emit backendStateChanged(QWifiManager::NotRunning);
-    }
 }
 
 bool QWifiController::resetSupplicantSocket()
 {
     qCDebug(B2QT_WIFI) << "reset supplicant socket";
     exitWifiEventThread();
-    if (!m_supplicant->stopSupplicant())
-        qCWarning(B2QT_WIFI) << "failed to stop supplicant!";
+    m_supplicant->stopSupplicant();
     m_supplicant->closeSupplicantConnection();
-    qCDebug(B2QT_WIFI) << "start supplicant";
-    if (!m_supplicant->startSupplicant()) {
-        qCWarning(B2QT_WIFI) << "failed to start a supplicant!";
+    if (!m_supplicant->startSupplicant())
         return false;
-    }
-    qCDebug(B2QT_WIFI) << "connect to supplicant";
-    if (!m_supplicant->connectToSupplicant()) {
-        qCWarning(B2QT_WIFI) << "failed to connect to a supplicant!";
+    if (!m_supplicant->connectToSupplicant())
         return false;
-    }
+
     startWifiEventThread();
     return true;
 }
@@ -180,20 +179,25 @@ void QWifiController::terminateBackend()
 {
     qCDebug(B2QT_WIFI) << "terminating wifi backend";
     emit backendStateChanged(QWifiManager::Terminating);
+
     exitWifiEventThread();
-    if (!m_supplicant->stopSupplicant())
-        qCWarning(B2QT_WIFI) << "failed to stop supplicant!";
+    m_supplicant->stopSupplicant();
     m_supplicant->closeSupplicantConnection();
 
-    qCDebug(B2QT_WIFI) << "run ifconfig (down)";
     QProcess ifconfig;
-    ifconfig.start(QStringLiteral("ifconfig"), QStringList() << QLatin1String(m_interface) << QStringLiteral("down"));
+    ifconfig.start(QStringLiteral("ifconfig"),
+                   QStringList() << QLatin1String(m_interface) << QStringLiteral("down"));
+    if (!ifconfig.waitForStarted()) {
+        m_managerPrivate->updateLastError(ifconfig.program() + QLatin1String(": ") + ifconfig.errorString());
+        return;
+    }
+
     ifconfig.waitForFinished();
-    if (ifconfig.exitStatus() != QProcess::NormalExit && ifconfig.exitCode() != 0)
-        qCWarning(B2QT_WIFI) << "failed to bring down wifi interface!";
+    QByteArray error = ifconfig.readAllStandardError();
+    if (!error.isEmpty())
+        m_managerPrivate->updateLastError(QLatin1String("failed to bring down wifi interface: " + error));
 
     stopDhcp();
-    qCDebug(B2QT_WIFI) << "wifi backend stopped successfully";
     emit backendStateChanged(QWifiManager::NotRunning);
 }
 
@@ -209,7 +213,7 @@ void QWifiController::exitWifiEventThread()
         m_exitEventThread = true;
         m_managerPrivate->call(QStringLiteral("SCAN"));
         if (!m_eventThread->wait(8000))
-            qCWarning(B2QT_WIFI, "timed out waiting for wifi event thread to exit!");
+            qCWarning(B2QT_WIFI, "timed out waiting for wifi event thread to exit");
     }
 }
 
@@ -227,7 +231,7 @@ void QWifiController::killDhcpProcess(const QString &path) const
     bool ok;
     int pid = pidFile.readAll().trimmed().toInt(&ok);
     if (!ok) {
-        qCWarning(B2QT_WIFI) << "pid is not a number!";
+        qCWarning(B2QT_WIFI) << "pid is not a number";
         return;
     }
 
@@ -245,13 +249,22 @@ void QWifiController::acquireIPAddress()
 
     QProcess udhcpc;
     udhcpc.start(QStringLiteral("udhcpc"), args);
-    udhcpc.waitForFinished();
-    if (udhcpc.exitStatus() != QProcess::NormalExit && udhcpc.exitCode() != 0)
-        qCWarning(B2QT_WIFI) << "udhcpc process failed!";
+    if (!udhcpc.waitForStarted()) {
+        m_managerPrivate->updateLastError(udhcpc.program() + QLatin1String(": ") + udhcpc.errorString());
+        emit dhcpRequestFinished(QLatin1String("failed"));
+        return;
+    }
 
+    udhcpc.waitForFinished();
+    QByteArray error = udhcpc.readAllStandardError();
     QString status = QLatin1String("success");
-    if (udhcpc.readAll().contains("No lease"))
+    if (!error.isEmpty()) {
+        m_managerPrivate->updateLastError(QLatin1String("udhcpc failed: " + error));
         status = QLatin1String("failed");
+    } else {
+        if (udhcpc.readAllStandardOutput().contains("No lease"))
+            status = QLatin1String("failed");
+    }
 
     emit dhcpRequestFinished(status);
 }
diff --git a/src/wifi/qwifimanager.cpp b/src/wifi/qwifimanager.cpp
index 6f733ba..0448ec7 100644
--- a/src/wifi/qwifimanager.cpp
+++ b/src/wifi/qwifimanager.cpp
@@ -110,6 +110,11 @@ void QWifiManagerPrivate::updateWifiState()
 {
     QProcess ps;
     ps.start(QStringLiteral("ps"));
+    if (!ps.waitForStarted()) {
+        updateLastError(ps.program() + QLatin1String(": ") + ps.errorString());
+        return;
+    }
+
     ps.waitForFinished();
     bool supplicantRunning = ps.readAll().contains("wpa_supplicant");
     if (supplicantRunning && m_wifiController->resetSupplicantSocket())
@@ -124,7 +129,7 @@ QString QWifiManagerPrivate::call(const QString &command)
     QByteArray reply;
     bool success = m_wifiController->supplicant()->sendCommand(command, &reply);
     if (!success) {
-        qCDebug(B2QT_WIFI) << "call to supplicant failed!";
+        qCDebug(B2QT_WIFI) << "call to supplicant failed";
         return QString();
     }
 
@@ -216,7 +221,7 @@ QWifiManager::QWifiManager()
 
     if (!QWifiDevice::wifiSupported())
         qCWarning(B2QT_WIFI) << "WifiManager may not work as expected on this device. Use the API provided by QtWifi "
-                      "library to verify if device has support for Wi-Fi before creating an instance of wifi manager!";
+                      "library to verify if device has support for Wi-Fi before creating an instance of wifi manager";
 
     d->m_wifiController = new QWifiController(this, d_ptr);
     QObject::connect(d->m_wifiController, &QWifiController::backendStateChanged,
@@ -413,7 +418,7 @@ bool QWifiManager::connect(QWifiConfiguration *config)
 {
     Q_D(QWifiManager);
     if (d->m_backendState != Running) {
-        qCWarning(B2QT_WIFI) << "start wifi backend before calling connect() !";
+        qCWarning(B2QT_WIFI) << "start wifi backend before calling connect()";
         return false;
     }
 
@@ -438,7 +443,7 @@ bool QWifiManager::connect(QWifiConfiguration *config)
         id = d->call(QStringLiteral("ADD_NETWORK"));
         id.toInt(&ok);
         if (!ok) {
-            d->updateLastError(QStringLiteral("failed to add network!"));
+            d->updateLastError(QStringLiteral("failed to add network"));
             return false;
         }
     }
diff --git a/src/wifi/qwifisupplicant.cpp b/src/wifi/qwifisupplicant.cpp
index b2ec497..5bab8c4 100644
--- a/src/wifi/qwifisupplicant.cpp
+++ b/src/wifi/qwifisupplicant.cpp
@@ -18,6 +18,7 @@
 ****************************************************************************/
 #include "qwifisupplicant_p.h"
 #include "qwifidevice.h"
+#include "qwifimanager_p.h"
 
 #include <poll.h>
 #include <unistd.h>
@@ -33,11 +34,12 @@ Q_LOGGING_CATEGORY(B2QT_WIFI_VERBOSE, "qt.b2qt.wifi.verbose")
 #define CONFIG_FILE "/etc/wpa_supplicant.qtwifi.conf"
 #define CONTROL_INTERFACE_PATH "/var/run/wpa_supplicant/"
 
-QWifiSupplicant::QWifiSupplicant(QObject *parent) :
+QWifiSupplicant::QWifiSupplicant(QObject *parent, QWifiManagerPrivate *managerPrivate) :
     QObject(parent),
     ctrl_conn(0),
     monitor_conn(0),
-    interface(QWifiDevice::wifiInterfaceName())
+    interface(QWifiDevice::wifiInterfaceName()),
+    m_managerPrivate(managerPrivate)
 {
     createSupplicantConfig();
 }
@@ -53,7 +55,7 @@ void QWifiSupplicant::createSupplicantConfig() const
                                "ctrl_interface_group=0\n"
                                "update_config=1\n");
     } else {
-        qCWarning(B2QT_WIFI) << "failed to create supplicant configuration file.";
+        m_managerPrivate->updateLastError(QLatin1String("failed to create wpa_supplicant configuration file."));
     }
 }
 
@@ -71,13 +73,17 @@ bool QWifiSupplicant::startSupplicant()
     arg << QLatin1String(CONFIG_FILE) << QStringLiteral("-D") << driver;
 
     QProcess startStopDaemon;
+    startStopDaemon.setProcessChannelMode(QProcess::MergedChannels);
     startStopDaemon.start(QStringLiteral("start-stop-daemon"), arg);
+    if (!startStopDaemon.waitForStarted()) {
+        m_managerPrivate->updateLastError(startStopDaemon.program() + QLatin1String(": ") + startStopDaemon.errorString());
+        return false;
+    }
     startStopDaemon.waitForFinished();
-    qCDebug(B2QT_WIFI) << startStopDaemon.readAll();
-
     // if the interface socket exists then wpa-supplicant was invoked successfully
     if (!QFile(QLatin1String(CONTROL_INTERFACE_PATH + interface)).exists()) {
-        qCWarning(B2QT_WIFI) << "failed to invoke wpa_supplicant!\n" << startStopDaemon.readAll();
+        m_managerPrivate->updateLastError(QLatin1String("failed to invoke wpa_supplicant: "
+                                                        + startStopDaemon.readAll()));
         return false;
     }
     // reset sockets used for exiting from hung state
@@ -96,9 +102,14 @@ bool QWifiSupplicant::stopSupplicant()
 
         QProcess startStopDaemon;
         startStopDaemon.start(QStringLiteral("start-stop-daemon"), arg);
+        if (!startStopDaemon.waitForStarted()) {
+            m_managerPrivate->updateLastError(startStopDaemon.program() + QLatin1String(": ") + startStopDaemon.errorString());
+            return false;
+        }
         startStopDaemon.waitForFinished();
-        if (startStopDaemon.exitStatus() != QProcess::NormalExit) {
-            qCWarning(B2QT_WIFI) << "failed to stop a supplicant process!\n" << startStopDaemon.readAll();
+        QByteArray error = startStopDaemon.readAllStandardError();
+        if (!error.isEmpty()) {
+            m_managerPrivate->updateLastError(QLatin1String("failed to stop a wpa_supplicant process" + error));
             return false;
         }
 
@@ -119,34 +130,37 @@ bool QWifiSupplicant::connectToSupplicant()
 {
     static char path[4096];
     snprintf(path, sizeof(path), "%s/%s", CONTROL_INTERFACE_PATH, interface.constData());
+    bool connected = true;
 
     ctrl_conn = wpa_ctrl_open(path);
     if (ctrl_conn == NULL) {
-        qCWarning(B2QT_WIFI, "Unable to open connection to supplicant on \"%s\": %s",
+        qCWarning(B2QT_WIFI, "Unable to open connection to wpa_supplicant on \"%s\": %s",
                   path, strerror(errno));
-        return false;
+        connected = false;
     }
     monitor_conn = wpa_ctrl_open(path);
     if (monitor_conn == NULL) {
         wpa_ctrl_close(ctrl_conn);
         ctrl_conn = NULL;
-        return false;
+        connected = false;
     }
     if (wpa_ctrl_attach(monitor_conn) != 0) {
         wpa_ctrl_close(monitor_conn);
         wpa_ctrl_close(ctrl_conn);
         ctrl_conn = monitor_conn = NULL;
-        return false;
+        connected = false;
     }
 
     if (socketpair(AF_UNIX, SOCK_STREAM, 0, exit_sockets) == -1) {
         wpa_ctrl_close(monitor_conn);
         wpa_ctrl_close(ctrl_conn);
         ctrl_conn = monitor_conn = NULL;
-        return false;
+        connected = false;
     }
 
-    return true;
+    if (!connected)
+        m_managerPrivate->updateLastError(QLatin1String("failed to connect to wpa_supplicant"));
+    return connected;
 }
 
 void QWifiSupplicant::closeSupplicantConnection()
@@ -263,7 +277,7 @@ bool QWifiSupplicant::sendCommand(const QString &command, QByteArray *reply)
     }
 
     if (len == sizeof(data) - 1) {
-        qCWarning(B2QT_WIFI) << "possible buffer overflow detected!";
+        qCWarning(B2QT_WIFI) << "possible buffer overflow detected";
         return false;
     }
 
diff --git a/src/wifi/qwifisupplicant_p.h b/src/wifi/qwifisupplicant_p.h
index 3b18380..0a6a964 100644
--- a/src/wifi/qwifisupplicant_p.h
+++ b/src/wifi/qwifisupplicant_p.h
@@ -30,11 +30,13 @@ QT_BEGIN_NAMESPACE
 Q_DECLARE_LOGGING_CATEGORY(B2QT_WIFI)
 Q_DECLARE_LOGGING_CATEGORY(B2QT_WIFI_VERBOSE)
 
+class QWifiManagerPrivate;
+
 class QWifiSupplicant : public QObject
 {
     Q_OBJECT
 public:
-    explicit QWifiSupplicant(QObject *parent = 0);
+    explicit QWifiSupplicant(QObject *parent, QWifiManagerPrivate *managerPrivate);
 
     void createSupplicantConfig() const;
     bool startSupplicant();
@@ -53,6 +55,7 @@ private:
     wpa_ctrl *monitor_conn;
     int exit_sockets[2];
     QByteArray interface;
+    QWifiManagerPrivate *const m_managerPrivate;
 };
 
 QT_END_NAMESPACE