Superkaramba: add GPU load sensor

The sensor has a required `driver` parameter and an optional `gpu` parameter.
- The former specifies the backend to use to query the system about GPU load.
- The latter specifies the id of the GPU to check. If left out, the backend default will be used.

For now it only supports NVidia GPUs via the `nvidia` driver, but it can be extended.

Signed-off-by: Mavridis Philippe <mavridisf@gmail.com>

5 files changed, 207 insertions, 5 deletions

diff --git a/superkaramba/src/CMakeLists.txt b/superkaramba/src/CMakeLists.txt
index 211ee0c..c38d41b 100644
--- a/superkaramba/src/CMakeLists.txt
+++ b/superkaramba/src/CMakeLists.txt
@@ -53,8 +53,8 @@ tde_add_executable( superkaramba AUTOMOC
     sknewstuff.h sknewstuff.cpp
     superkarambasettings.kcfgc themelocale.cpp
     input.cpp sklineedit.cpp input_python.cpp
-    svcgrp_python.cpp
-  LINK tdeio-shared ${PYTHON_LIBRARIES} 
+    svcgrp_python.cpp gpusensor.cpp
+  LINK tdeio-shared ${PYTHON_LIBRARIES}
     ${TDENEWSTUFF_LIBRARIES}
     ${LIBKVM_LIBRARIES}
   DESTINATION ${BIN_INSTALL_DIR}
diff --git a/superkaramba/src/gpusensor.cpp b/superkaramba/src/gpusensor.cpp
new file mode 100644
index 0000000..d95de59
--- /dev/null
+++ b/superkaramba/src/gpusensor.cpp
@@ -0,0 +1,129 @@
+/*******************************************************************************
+  GPU sensor
+  Copyright (C) 2024 Mavridis Philippe <mavridisf@gmail.com>
+
+  This program is free software: you can redistribute it and/or modify it under
+  the terms of the GNU General Public License as published by the Free Software
+  Foundation, either version 3 of the License, or (at your option) any later
+  version.
+
+  This program is distributed in the hope that it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+  You should have received a copy of the GNU General Public License along with
+  this program. If not, see <http://www.gnu.org/licenses/>.
+
+  Improvements and feedback are welcome!
+*******************************************************************************/
+
+// TQt
+#include <tqregexp.h>
+
+// TDE
+#include <kstandarddirs.h>
+#include <kdebug.h>
+
+// Superkaramba
+#include "gpusensor.h"
+
+GPUSensor::GPUSensor(TQString gpuDriver, TQString gpuId, int interval)
+    : Sensor(interval), m_gpuDriver(gpuDriver), m_gpuId(gpuId)
+{
+    if (m_gpuDriver.lower() == "nvidia")
+    {
+        TQString nvsmi = TDEStandardDirs::findExe("nvidia-smi");
+        if (nvsmi.isNull())
+        {
+            kdError() << "The NVidia System Management Interface software is not avaiable." << endl;
+            return;
+        }
+
+        m_command << nvsmi << "--query-gpu" << "utilization.gpu"
+                           << "--format=csv,noheader";
+
+        if (!m_gpuId.isNull())
+        {
+            m_command << TQString("--id=%1").arg(m_gpuId);
+        }
+    }
+
+    else
+    {
+        kdError() << "Unsupported driver specified for GPU sensor (" << m_gpuDriver << ");" << endl
+                  << "\tSupported drivers are: nvidia" << endl;
+    }
+
+    connect(&m_proc, TQ_SIGNAL(receivedStdout(TDEProcess*, char*, int)),
+            this, TQ_SLOT(receivedStdout(TDEProcess*, char*, int)));
+    connect(&m_proc, TQ_SIGNAL(processExited(TDEProcess*)),
+            this, TQ_SLOT(processExited(TDEProcess*)));
+}
+
+GPUSensor::~GPUSensor()
+{
+}
+
+void GPUSensor::update()
+{
+    if (m_command.isEmpty()) return;
+
+    m_proc.clearArguments();
+    m_proc << m_command;
+
+    m_proc.start(TDEProcess::NotifyOnExit, TDEProcess::Stdout);
+}
+
+void GPUSensor::receivedStdout(TDEProcess *proc, char *buffer, int buflen)
+{
+    buffer[buflen] = 0;
+    m_buffer += TQCString(buffer);
+}
+
+TQString GPUSensor::getLoad()
+{
+    if (m_gpuDriver.lower() == "nvidia")
+    {
+        return m_buffer.left(m_buffer.length() - 3);
+    }
+
+    return TQString::null;
+}
+
+#define SUB_FORMAT_STR(fstring, value) \
+    format.replace(TQRegExp(#fstring, false), value)
+void GPUSensor::processExited(TDEProcess *proc)
+{
+    SensorParams *sp;
+    Meter *meter;
+    TQString format;
+    TQString load = getLoad();
+    m_buffer = TQString::null;
+
+    TQObjectListIt it(*objList);
+    while (it != 0)
+    {
+        sp = (SensorParams*)(*it);
+        meter = sp->getMeter();
+        format = sp->getParam("FORMAT");
+
+        if( format.length() == 0)
+        {
+            format = "%v";
+        }
+
+        SUB_FORMAT_STR(%load, load);
+        SUB_FORMAT_STR(%v,    load);
+
+        meter->setValue(format);
+        ++it;
+    }
+}
+
+#undef SUB_FORMAT_STR
+
+void GPUSensor::setMaxValue(SensorParams *sp)
+{
+    sp->getMeter()->setMax(100);
+}
+
+#include "gpusensor.moc"
\ No newline at end of file
diff --git a/superkaramba/src/gpusensor.h b/superkaramba/src/gpusensor.h
new file mode 100644
index 0000000..178e52e
--- /dev/null
+++ b/superkaramba/src/gpusensor.h
@@ -0,0 +1,52 @@
+/*******************************************************************************
+  GPU sensor
+  Copyright (C) 2024 Mavridis Philippe <mavridisf@gmail.com>
+
+  This program is free software: you can redistribute it and/or modify it under
+  the terms of the GNU General Public License as published by the Free Software
+  Foundation, either version 3 of the License, or (at your option) any later
+  version.
+
+  This program is distributed in the hope that it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+  You should have received a copy of the GNU General Public License along with
+  this program. If not, see <http://www.gnu.org/licenses/>.
+
+  Improvements and feedback are welcome!
+*******************************************************************************/
+
+#ifndef GPUSENSOR_H
+#define GPUSENSOR_H
+
+// TDE
+#include <kprocess.h>
+
+// Superkaramba
+#include "sensor.h"
+
+class GPUSensor : public Sensor
+{
+    TQ_OBJECT
+
+    public:
+        GPUSensor(TQString driver, TQString gpuId, int interval = 1000);
+        ~GPUSensor();
+
+        void update();
+        void setMaxValue(SensorParams *sp);
+
+    protected:
+        TQString getLoad();
+
+    private:
+        TQString m_gpuDriver, m_gpuId, m_buffer;
+        TQStringList m_command;
+        TDEProcess m_proc;
+
+    public slots:
+        void receivedStdout(TDEProcess *proc, char *buffer, int buflen);
+        void processExited(TDEProcess *proc);
+};
+
+#endif // GPUSENSOR_H
\ No newline at end of file
diff --git a/superkaramba/src/karamba.cpp b/superkaramba/src/karamba.cpp
index d4a74f7..d828411 100644
--- a/superkaramba/src/karamba.cpp
+++ b/superkaramba/src/karamba.cpp
@@ -988,6 +988,26 @@ void karamba::setSensor(const LineParser& lineParser, Meter* meter)
 
   }
 
+  if (sens == "GPU")
+  {
+      TQString gpuId = lineParser.getString("GPU");
+      TQString gpuDriver = lineParser.getString("DRIVER");
+      TQString sensorId = TQString("GPU_%1_%2").arg(gpuDriver, gpuId);
+      sensor = sensorMap[sensorId];
+      if (sensor == 0)
+      {
+          int interval = lineParser.getInt("INTERVAL");
+          interval = (interval == 0) ? 1000 : interval;
+          sensor = (sensorMap[sensorId] = new GPUSensor(gpuDriver, gpuId, interval));
+          sensorList->append(sensor);
+      }
+
+      SensorParams *sp = new SensorParams(meter);
+      sp->addParam("FORMAT", m_theme.locale()->translate(lineParser.getString("FORMAT").ascii()));
+      sensor->addMeter(sp);
+      sensor->setMaxValue(sp);
+  }
+
   if( sens == "MEMORY" )
   {
     sensor = sensorMap["MEMORY"];
diff --git a/superkaramba/src/karamba.h b/superkaramba/src/karamba.h
index 57843d7..77f8f5c 100644
--- a/superkaramba/src/karamba.h
+++ b/superkaramba/src/karamba.h
@@ -82,6 +82,7 @@
 #include "uptimesensor.h"
 #include "memsensor.h"
 #include "cpusensor.h"
+#include "gpusensor.h"
 #include "networksensor.h"
 #include "xmmssensor.h"
 #include "noatunsensor.h"
@@ -112,7 +113,7 @@ class LineParser;
 class karamba :  public TQWidget
 {
     TQ_OBJECT
-  
+
 
 public:
     karamba(TQString fn, TQString name, bool reloading = false,
@@ -327,7 +328,7 @@ private slots:
 class DesktopChangeSlot : public TQObject
 {
   TQ_OBJECT
-  
+
 
   public:
   DesktopChangeSlot(TQObject *parent, int desktop_id);
@@ -348,7 +349,7 @@ class DesktopChangeSlot : public TQObject
 class SignalBridge : public TQObject
 {
   TQ_OBJECT
-  
+
 
   public:
     SignalBridge(TQObject* parent, TQString, TDEActionCollection*);