add unix implementation for DefaultInterfaceIP

src/gui/src/DefaultInterfaceIP.h

@@ -1,10 +1,10 @@
-#pragma once
-
-#include <string>
-
-namespace Debauchee
-{
-
-std::string default_interface_ip();
-
-}
+#pragma once
+
+#include <string>
+
+namespace Debauchee
+{
+
+std::string default_interface_ip();
+
+}

src/gui/src/ZeroconfService.cpp

@@ -20,6 +20,7 @@
 #include "MainWindow.h"
 #include "ZeroconfRegister.h"
 #include "ZeroconfBrowser.h"
+#include "DefaultInterfaceIP.h"
 
 #include <QtNetwork>
 #include <QMessageBox>
@@ -30,7 +31,6 @@
 #ifdef _WIN32
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
-#include "win32/DefaultInterfaceIP.h"
 #else
 #include <stdlib.h>
 #endif
@@ -119,29 +119,6 @@ void ZeroconfService::errorHandle(DNSServiceErrorType errorCode)
         tr("Error code: %1.").arg(errorCode));
 }
 
-QString ZeroconfService::getLocalIPAddresses()
-{
-#ifdef _WIN32
-    return QString::fromStdString(Debauchee::default_interface_ip());
-#else
-    const QString NonEthernetMAC = "00:00:00:00:00:00";
-    foreach(const auto qni, QNetworkInterface::allInterfaces()) {
-        // weed out loopback, inactive, and non-ethernet interfaces
-        if (!qni.flags().testFlag(QNetworkInterface::IsLoopBack) &&
-            qni.flags().testFlag(QNetworkInterface::IsUp) &&
-            qni.hardwareAddress() != NonEthernetMAC) {
-            foreach(const auto address, qni.allAddresses()) {
-                if (address.protocol() == QAbstractSocket::IPv4Protocol) {
-                    // use the first address we find
-                    return address.toString();
-                }
-            }
-        }
-    }
-    return "";
-#endif
-}
-
 bool ZeroconfService::registerService(bool server)
 {
     bool result = true;
@@ -156,7 +133,7 @@ bool ZeroconfService::registerService(bool server)
         else {
             m_pZeroconfRegister = new ZeroconfRegister(this);
             if (server) {
-                QString localIP = getLocalIPAddresses();
+                QString localIP = QString::fromStdString(Debauchee::default_interface_ip());
                 if (localIP.isEmpty()) {
                     QMessageBox::warning(m_pMainWindow, tr("Barrier"),
                         tr("Failed to get local IP address. "

src/gui/src/ZeroconfService.h

@@ -42,7 +42,6 @@ private slots:
     void errorHandle(DNSServiceErrorType errorCode);
 
 private:
-    QString getLocalIPAddresses();
     bool registerService(bool server);
 
 private:

src/gui/src/unix/DefaultInterfaceIP.cpp

@@ -0,0 +1,55 @@
+#include <string>
+#include <cstring>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <linux/wireless.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include "SocketResource.h"
+#include "IfAddrsResource.h"
+
+namespace Debauchee
+{
+
+static bool is_wireless(const char * ifname)
+{
+    if (ifname) {
+        SocketResource fd(AF_INET, SOCK_STREAM, 0);
+        if (fd.is_valid()) {
+            struct iwreq req { 0 };
+            ::strncpy(req.ifr_name, ifname, IFNAMSIZ - 1);
+            return ioctl(fd, SIOCGIWMODE, req) >= 0;
+        }
+    }
+    return false;
+}
+
+std::string default_interface_ip()
+{
+    std::string wirelessAddress;
+    IfAddrsResource ifa;
+    if (ifa.is_valid()) {
+        for (struct ifaddrs * next = ifa; next; next = next->ifa_next) {
+            auto sain = (struct sockaddr_in *)next->ifa_addr;
+            if (!sain || sain->sin_family != AF_INET ||
+                !(next->ifa_flags & IFF_RUNNING) ||
+                (next->ifa_flags & IFF_LOOPBACK)
+               ) {
+                continue;
+            }
+            std::string address = inet_ntoa(sain->sin_addr);
+            // take first wired address right away
+            if (!is_wireless(next->ifa_name)) {
+                return address;
+            }
+            // save first wireless address to be used if we don't find a wired one
+            if (wirelessAddress.empty()) {
+                wirelessAddress = address;
+            }
+        }
+    }
+    return wirelessAddress;
+}
+
+}
+

src/gui/src/unix/IfAddrsResource.h

@@ -0,0 +1,32 @@
+#include <sys/types.h>
+#include <ifaddrs.h>
+
+namespace Debauchee
+{
+
+class IfAddrsResource
+{
+public:
+    explicit IfAddrsResource() :
+        _valid(getifaddrs(&_ifa) == 0)
+    {
+    }
+
+    ~IfAddrsResource()
+    {
+        if (_valid) {
+            freeifaddrs(_ifa);
+        }
+    }
+
+    bool is_valid() const { return _valid; }
+
+    operator struct ifaddrs * () const { return _ifa; }
+
+private:
+    bool _valid;
+    struct ifaddrs * _ifa;
+};
+
+}
+

src/gui/src/unix/SocketResource.h

@@ -0,0 +1,31 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+
+namespace Debauchee
+{
+
+class SocketResource
+{
+public:
+    explicit SocketResource(int domain, int type, int protocol) :
+        _fd(socket(domain, type, protocol))
+    {
+    }
+
+    ~SocketResource()
+    {
+        if (is_valid()) {
+            close(_fd);
+        }
+    }
+
+    bool is_valid() const { return _fd >= 0; }
+
+    operator int() const { return _fd; }
+
+private:
+    int _fd;
+};
+
+}
+