Retreive link speed and MTU for Linux ports

server/drone.pro

@@ -59,6 +59,7 @@ SOURCES += \
     bsdport.cpp \
     linuxhostdevice.cpp \
     linuxport.cpp \
+    linuxutils.cpp \
     params.cpp \
     winhostdevice.cpp \
     winpcapport.cpp 

server/linuxport.cpp

@@ -20,6 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>
 #include "linuxport.h"
 
 #include "interfaceinfo.h"
+#include "linuxutils.h"
 
 #ifdef Q_OS_LINUX
 
@@ -243,11 +244,13 @@ void LinuxPort::populateInterfaceInfo()
         return;
     }
 
+    interfaceInfo_ = new InterfaceInfo;
+    interfaceInfo_->speed = sysfsAttrib(name(), "speed").toDouble();
+    interfaceInfo_->mtu = rtnl_link_get_mtu(link);
+
     int ifIndex = rtnl_link_get_ifindex(link);
     rtnl_link_put(link);
 
-    interfaceInfo_ = new InterfaceInfo;
-    // FIXME: speed, mtu
     interfaceInfo_->mac = mac;
 
     //

server/linuxutils.cpp

@@ -0,0 +1,65 @@
+/*
+Copyright (C) 2021 Srivats P.
+
+This file is part of "Ostinato"
+
+This 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/>
+*/
+
+#include "linuxutils.h"
+
+#include <QFile>
+#include <QTextStream>
+
+// Reads a text file (size < 4K) and returns content as a string
+// A terminating \n will be removed
+// There's no way to distinguish an empty file and error while reading
+QString readTextFile(QString fileName)
+{
+    QFile file(fileName);
+    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        qWarning("Can't read %s", qUtf8Printable(fileName));
+        return QString();
+    }
+
+    if (file.size() > 4096) {
+        qWarning("Can't read %s - too large (%lld)",
+                 qUtf8Printable(fileName), file.size());
+        return QString();
+    }
+
+    QTextStream in(&file);
+    QString text = in.readAll();
+    file.close();
+
+    if (text.endsWith('\n'))
+        text.chop(1);
+
+    return text;
+}
+
+// Reads value from /sys/class/net/<device>/<attrib-path>
+// and returns as string
+// XXX: reading from sysfs is discouraged
+QString sysfsAttrib(const char *device, const char *attribPath)
+{
+    return readTextFile(QString("/sys/class/net/%1/%2")
+                            .arg(device).arg(attribPath));
+}
+
+// Convenience overload
+QString sysfsAttrib(QString device, const char *attribPath)
+{
+    return sysfsAttrib(qPrintable(device), attribPath);
+}

server/linuxutils.h

@@ -0,0 +1,29 @@
+/*
+Copyright (C) 2021 Srivats P.
+
+This file is part of "Ostinato"
+
+This 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/>
+*/
+
+#ifndef _LINUX_UTILS_H
+#define _LINUX_UTILS_H
+
+#include <QString>
+
+QString readTextFile(QString fileName);
+QString sysfsAttrib(const char *device, const char *attribPath);
+QString sysfsAttrib(QString device, const char *attribPath);
+
+#endif