Make error conditions more clear

Change-Id: I5b27907883ecebd7572b3b7e400179a240199f8f
Reviewed-by: Kari Oikarinen <kari.oikarinen@qt.io>
Reviewed-by: Samuli Piippo <samuli.piippo@qt.io>

4 files changed, 10 insertions, 10 deletions

diff --git a/qdb/server/usb-host/libusbcontext.cpp b/qdb/server/usb-host/libusbcontext.cpp
index c4c0fd0..1ad66ae 100644
--- a/qdb/server/usb-host/libusbcontext.cpp
+++ b/qdb/server/usb-host/libusbcontext.cpp
@@ -41,7 +41,7 @@ struct LibUsbContext
         : context{nullptr}
     {
         int ret = libusb_init(&context);
-        if (ret) {
+        if (ret != LIBUSB_SUCCESS) {
             qCCritical(usbC) << "Could not initialize libusb";
         }
     }
diff --git a/qdb/server/usb-host/usbconnection.cpp b/qdb/server/usb-host/usbconnection.cpp
index 3c8f3e4..360208d 100644
--- a/qdb/server/usb-host/usbconnection.cpp
+++ b/qdb/server/usb-host/usbconnection.cpp
@@ -74,7 +74,7 @@ bool UsbConnection::open(OpenMode mode)
 
     libusb_config_descriptor *config;
     int ret = libusb_get_active_config_descriptor(m_device.pointer(), &config);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         qCWarning(usbC) << "Could not get config descriptor:" << libusb_error_name(ret);
         return false;
     }
@@ -83,7 +83,7 @@ bool UsbConnection::open(OpenMode mode)
     };
 
     ret = libusb_open(m_device.pointer(), &m_handle);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         if (ret == LIBUSB_ERROR_ACCESS) {
             qCWarning(usbC) << "Access to USB device was denied."
                             << "Check the manual for setting up access to USB devices.";
@@ -100,7 +100,7 @@ bool UsbConnection::open(OpenMode mode)
     }
 
     ret = libusb_claim_interface(m_handle, m_interfaceInfo.number);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         qCDebug(usbC) << "Could not claim interface:" << libusb_error_name(ret);
         return false;
     }
@@ -131,7 +131,7 @@ qint64 UsbConnection::writeData(const char *data, qint64 maxSize)
 
     int transferred = 0;
     int ret = libusb_bulk_transfer(m_handle, m_interfaceInfo.outAddress, (unsigned char*)data, size, &transferred, 0);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         qCCritical(usbC) << "Could not write message header:" << libusb_error_name(ret);
         return -1;
     }
@@ -141,7 +141,7 @@ qint64 UsbConnection::writeData(const char *data, qint64 maxSize)
     if (size < maxSize) {
         int rest = maxSize - size;
         int ret = libusb_bulk_transfer(m_handle, m_interfaceInfo.outAddress, (unsigned char*)data + size, rest, &transferred, 0);
-        if (ret) {
+        if (ret != LIBUSB_SUCCESS) {
             qCCritical(usbC) << "Could not write message payload:" << libusb_error_name(ret);
             return -1;
         }
diff --git a/qdb/server/usb-host/usbconnectionreader.cpp b/qdb/server/usb-host/usbconnectionreader.cpp
index 33d77c3..93688f3 100644
--- a/qdb/server/usb-host/usbconnectionreader.cpp
+++ b/qdb/server/usb-host/usbconnectionreader.cpp
@@ -56,7 +56,7 @@ void UsbConnectionReader::executeRead()
     int transferred = 0;
     int ret = libusb_bulk_transfer(m_handle, m_inAddress, reinterpret_cast<unsigned char *>(buffer.data()),
                                    buffer.size(), &transferred, quitCheckingTimeout);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         if (ret != LIBUSB_ERROR_TIMEOUT) {
             qCWarning(usbC) << "Could not read from USB connection:" << libusb_error_name(ret);
             ++m_errorCount;
diff --git a/qdb/server/usb-host/usbdeviceenumerator.cpp b/qdb/server/usb-host/usbdeviceenumerator.cpp
index 3bf8ff9..d2dc2a0 100644
--- a/qdb/server/usb-host/usbdeviceenumerator.cpp
+++ b/qdb/server/usb-host/usbdeviceenumerator.cpp
@@ -58,7 +58,7 @@ std::pair<bool, UsbInterfaceInfo> findQdbInterface(libusb_device *device)
 {
     libusb_config_descriptor *config;
     const int ret = libusb_get_active_config_descriptor(device, &config);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         const auto address = getAddress(device);
         qCWarning(usbC) << "Could not get config descriptor for device at"
                         << address.busNumber << ":" << address.deviceAddress
@@ -92,7 +92,7 @@ QString getSerialNumber(libusb_device *device, libusb_device_handle *handle)
 
     libusb_device_descriptor desc;
     int ret = libusb_get_device_descriptor(device, &desc);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         qCCritical(usbC) << "Could not get device descriptor" << libusb_error_name(ret);
         return serial;
     }
@@ -130,7 +130,7 @@ std::pair<bool, UsbDevice> makeUsbDeviceIfQdbDevice(libusb_device *device)
 
     libusb_device_handle *handle;
     int ret = libusb_open(device, &handle);
-    if (ret) {
+    if (ret != LIBUSB_SUCCESS) {
         const auto address = getAddress(device);
         if (ret == LIBUSB_ERROR_ACCESS) {
             qCWarning(usbC) << "Access to USB device at" << address.busNumber