kfreespace: default to 1/10 of the total space

credits to Benjamin Grant for making me do it, fallback is still 1 GB and
the configuration interface remains the same but the default should fit
more cases now

Signed-off-by: Ivailo Monev <xakepa10@gmail.com>

kfreespace/kcm/kfreespaceconfig.cpp

@@ -136,7 +136,7 @@ void KFreeSpaceBox::setDefault()
 {
     m_watchbox->setChecked(s_kfreespacewatch);
     m_checktimeinput->setValue(s_kfreespacechecktime);
-    m_freespaceinput->setValue(s_kfreespacefreespace);
+    m_freespaceinput->setValue(kCalculateFreeSpace(m_soliddevice, s_kfreespacefreespace));
 }
 
 void KFreeSpaceBox::slotWatch()
@@ -229,7 +229,7 @@ void KCMFreeSpace::load()
         KFreeSpaceBox* devicebox = new KFreeSpaceBox(
             this,
             soliddevice,
-            kfreespacewatch, kfreespacechecktime, kfreespacefreespace
+            kfreespacewatch, kfreespacechecktime, kCalculateFreeSpace(soliddevice, kfreespacefreespace)
         );
         m_deviceboxes.append(devicebox);
         connect(devicebox, SIGNAL(changed()), this, SLOT(slotDeviceChanged()));

kfreespace/kded/kded_kfreespace.cpp

@@ -95,7 +95,7 @@ void KFreeSpaceModule::slotInit()
         KFreeSpaceImpl* kfreespaceimpl = new KFreeSpaceImpl(this);
         const bool kfreespacestatus = kfreespaceimpl->watch(
             soliddevice,
-            kfreespacechecktime, kfreespacefreespace
+            kfreespacechecktime, kCalculateFreeSpace(soliddevice, kfreespacefreespace)
         );
         if (!kfreespacestatus) {
             delete kfreespaceimpl;

kfreespace/kded/kfreespaceimpl.cpp

@@ -21,7 +21,6 @@
 
 #include <QDir>
 #include <klocale.h>
-#include <kdiskfreespaceinfo.h>
 #include <knotification.h>
 #include <kdebug.h>
 #include <solid/storageaccess.h>
@@ -50,7 +49,7 @@ bool KFreeSpaceImpl::watch(const Solid::Device &soliddevice,
     // NOTE: time from config is in seconds, has to be in ms here
     m_checktime = (qBound(s_kfreespacechecktimemin, checktime, s_kfreespacechecktimemax) * 1000);
     // NOTE: size from config is in MB, has to be in bytes here
-    m_freespace = (qBound(s_kfreespacefreespacemin, freespace, s_kfreespacefreespacemax) * 1024 * 1024);
+    m_freespace = (kCalculateFreeSpace(soliddevice, freespace) * 1024 * 1024);
     m_timerid = startTimer(m_checktime);
     kDebug() << "Checking" << m_soliddevice.udi()
              << "every" << (m_checktime / 1000)

kfreespace/kfreespace.h

@@ -19,12 +19,40 @@
 #ifndef KFREESPACE_H
 #define KFREESPACE_H
 
+#include <kdiskfreespaceinfo.h>
+#include <solid/device.h>
+#include <solid/storagevolume.h>
+#include <kdebug.h>
+
 static const bool s_kfreespacewatch = true;
 static const qulonglong s_kfreespacechecktime = 60; // 1 minute
 static const qulonglong s_kfreespacechecktimemin = 1;
 static const qulonglong s_kfreespacechecktimemax = 60;
-static const qulonglong s_kfreespacefreespace = 1024; // 1 GB
+static const qulonglong s_kfreespacefreespace = 0; // either the value from the config or 1/10, fallback is 1024
 static const qulonglong s_kfreespacefreespacemin = 10;
 static const qulonglong s_kfreespacefreespacemax = 1024;
 
+static qulonglong kCalculateFreeSpace(const Solid::Device &soliddevice, const qulonglong freespace)
+{
+    const Solid::StorageVolume* solidvolume = soliddevice.as<Solid::StorageVolume>();
+    Q_ASSERT(solidvolume);
+    const qulonglong totalsize = solidvolume->size();
+    if (totalsize <= 0) {
+        // if the total size of the device cannot be obtained then the space is the one passed
+        // bound to min and max, unless the passed value does not come from config (freespace
+        // variable is zero)
+        if (freespace <= 0) {
+            return 1024;
+        }
+        return qBound(s_kfreespacefreespacemin, freespace, s_kfreespacefreespacemax);
+    }
+    const qulonglong autosize = (totalsize / 1024 / 1024 / 10);
+    // the case of not being specified, 1/10 of the total space bound to min and max
+    if (freespace <= 0) {
+        return qBound(s_kfreespacefreespacemin, autosize, s_kfreespacefreespacemax);
+    }
+    // else it is the one explicitly specified bound to min and max
+    return qBound(s_kfreespacefreespacemin, freespace, s_kfreespacefreespacemax);
+}
+
 #endif // KFREESPACE_H