Move LVM device scanning code.

Now it's the backend's responsibility to find LVM devices.
All LVM scanning code was moved into LvmDevice::scanSystemLVM helper,
so that it is very easy to plug LVM into backend.

LVM devices are now intentionally not detected in Dummy Backend.

README.md

@@ -71,9 +71,7 @@ back to a default backend suitable for the current platform.
 Calling KPMcore functions before the library is initialized will
 result in undefined behavior.
 
-### Devices [FIXME: WIP]
-
-#### Backend device scanner
+### Devices
 
 After the backend is initialized you can scan for available devices.
 If you only want devices from the loaded backend you can call
@@ -87,8 +85,7 @@ read only devices.
 
 #### KPMcore device scanner
 
-Alternatively, you can use KPMcore device scanner which also finds
-LVM Volume Groups.
+Alternatively, you can use KPMcore device scanner
 
 ```
     #include <core/device.h>
@@ -102,6 +99,6 @@ LVM Volume Groups.
     QList<Device*> devices = operationStack->previewDevices();
 ```
 
-When `deviceScanner` scans for the devices in a background thread. After
+Then `deviceScanner` scans for the devices in a background thread. After
 scanning is complete `DeviceScanner::finished()` signal will be emitted.
 Then the devices can accessed using `operationStack->previewDevices()`.

src/core/devicescanner.cpp

@@ -23,7 +23,6 @@
 
 #include "core/operationstack.h"
 #include "core/device.h"
-#include "core/lvmdevice.h"
 #include "core/diskdevice.h"
 
 #include "fs/lvm2_pv.h"
@@ -65,27 +64,10 @@ void DeviceScanner::scan()
     clear();
 
     const QList<Device*> deviceList = CoreBackendManager::self()->backend()->scanDevices();
-    const QList<LvmDevice*> lvmList = LvmDevice::scanSystemLVM();
-
-    // Some LVM operations require additional information about LVM physical volumes which we store in LVM::pvList
-    LVM::pvList = FS::lvm2_pv::getPVs(deviceList);
 
     for (const auto &d : deviceList)
         operationStack().addDevice(d);
 
-    // Display alphabetically sorted disk devices above LVM VGs
     operationStack().sortDevices();
-
-    // Look for LVM physical volumes in LVM VGs
-    for (const auto &d : lvmList) {
-        operationStack().addDevice(d);
-        LVM::pvList.append(FS::lvm2_pv::getPVinNode(d->partitionTable()));
-    }
-
-    // Inform LvmDevice about which physical volumes form that particular LvmDevice
-    for (const auto &d : lvmList)
-        for (const auto &p : qAsConst(LVM::pvList))
-            if (p.vgName() == d->name())
-                d->physicalVolumes().append(p.partition());
 }
 

src/core/lvmdevice.cpp

@@ -171,15 +171,30 @@ Partition* LvmDevice::scanPartition(const QString& lvPath, PartitionTable* pTabl
 
 /** scan and construct list of initialized LvmDevice objects.
  *
- *  @return list of initialized LvmDevices
+ *  @param devices list of initialized Devices
  */
-QList<LvmDevice*> LvmDevice::scanSystemLVM()
+void LvmDevice::scanSystemLVM(QList<Device*>& devices)
 {
     QList<LvmDevice*> lvmList;
     for (const auto &vgName : getVGs()) {
         lvmList.append(new LvmDevice(vgName));
     }
-    return lvmList;
+
+    // Some LVM operations require additional information about LVM physical volumes which we store in LVM::pvList
+    LVM::pvList = FS::lvm2_pv::getPVs(devices);
+
+    // Look for LVM physical volumes in LVM VGs
+    for (const auto &d : lvmList) {
+        devices.append(d);
+        LVM::pvList.append(FS::lvm2_pv::getPVinNode(d->partitionTable()));
+    }
+
+    // Inform LvmDevice about which physical volumes form that particular LvmDevice
+    for (const auto &d : lvmList)
+        for (const auto &p : qAsConst(LVM::pvList))
+            if (p.vgName() == d->name())
+                d->physicalVolumes().append(p.partition());
+
 }
 
 qint64 LvmDevice::mappedSector(const QString& lvPath, qint64 sector) const

src/core/lvmdevice.h

@@ -58,7 +58,7 @@ public:
     static QVector<const Partition*> s_DirtyPVs;
 
 public:
-    static QList<LvmDevice*> scanSystemLVM();
+    static void scanSystemLVM(QList<Device*>& devices);
 
     static const QStringList getVGs();
     static const QStringList getLVs(const QString& vgName);

src/core/operationstack.cpp

@@ -554,6 +554,10 @@ void OperationStack::addDevice(Device* d)
 
 static bool deviceLessThan(const Device* d1, const Device* d2)
 {
+    // Display alphabetically sorted disk devices above LVM VGs
+    if (d1->type() == Device::LVM_Device && d2->type() == Device::Disk_Device )
+        return false;
+
     return d1->deviceNode() <= d2->deviceNode();
 }
 

src/plugins/libparted/libpartedbackend.cpp

@@ -24,7 +24,7 @@
 #include "plugins/libparted/libparteddevice.h"
 #include "plugins/libparted/pedflags.h"
 
-#include "core/diskdevice.h"
+#include "core/lvmdevice.h"
 #include "core/partition.h"
 #include "core/partitiontable.h"
 #include "core/partitionalignment.h"
@@ -384,7 +384,7 @@ void LibPartedBackend::scanDevicePartitions(Device& d, PedDisk* pedDisk)
     @param deviceNode the device node (e.g. "/dev/sda")
     @return the created Device object. callers need to free this.
 */
-Device* LibPartedBackend::scanDevice(const QString& deviceNode)
+DiskDevice* LibPartedBackend::scanDevice(const QString& deviceNode)
 {
     PedDevice* pedDevice = ped_device_get(deviceNode.toLocal8Bit().constData());
 
@@ -456,6 +456,8 @@ QList<Device*> LibPartedBackend::scanDevices(bool excludeReadOnly)
                 result.append(device);
             }
         }
+
+        LvmDevice::scanSystemLVM(result);
     }
 
     return result;

src/plugins/libparted/libpartedbackend.h

@@ -23,6 +23,7 @@
 #include "backend/corebackend.h"
 
 #include "core/partitiontable.h"
+#include "core/diskdevice.h"
 #include "util/libpartitionmanagerexport.h"
 
 #include "fs/filesystem.h"
@@ -63,7 +64,7 @@ public:
     CoreBackendDevice* openDevice(const QString& deviceNode) override;
     CoreBackendDevice* openDeviceExclusive(const QString& deviceNode) override;
     bool closeDevice(CoreBackendDevice* core_device) override;
-    Device* scanDevice(const QString& deviceNode) override;
+    DiskDevice* scanDevice(const QString& deviceNode) override;
     QList<Device*> scanDevices(bool excludeReadOnly = false) override;
     FileSystem::Type detectFileSystem(const QString& partitionPath) override;