Fork netif_linux to netif_gnu.

netif_linux now uses linux specifics which do not work on GNU.

CMakeLists.txt

@@ -1198,7 +1198,7 @@ elseif(GNU)
     list(APPEND LIBFASTFETCH_SRC
         src/common/dbus.c
         src/common/io/io_unix.c
-        src/common/netif/netif_linux.c
+        src/common/netif/netif_gnu.c
         src/common/networking/networking_linux.c
         src/common/processing_linux.c
         src/detection/battery/battery_nosupport.c

src/common/netif/netif_gnu.c

@@ -0,0 +1,45 @@
+#include "netif.h"
+#include "common/io/io.h"
+
+#include <net/if.h>
+#include <stdio.h>
+
+#define FF_STR_INDIR(x) #x
+#define FF_STR(x) FF_STR_INDIR(x)
+
+static bool getDefaultRouteIPv4(char iface[IF_NAMESIZE + 1], uint32_t* ifIndex, uint32_t* preferredSourceAddr)
+{
+    if (preferredSourceAddr)
+        *preferredSourceAddr = 0;
+    // Based on netif_linux.c before 5e770dc8b019702ca458cc0cad46161ebec608a4
+    FILE* FF_AUTO_CLOSE_FILE netRoute = fopen("/proc/route", "r");
+
+    if (!netRoute) return false;
+
+    // skip first line
+    FF_UNUSED(fscanf(netRoute, "%*[^\n]\n"));
+
+    unsigned long long destination; //, gateway, flags, refCount, use, metric, mask, mtu, ...
+    while (fscanf(netRoute, "%" FF_STR(IF_NAMESIZE) "s%llx%*[^\n]", iface, &destination) == 2)
+    {
+        if (destination != 0) continue;
+        *ifIndex = if_nametoindex(iface);
+        return true;
+    }
+    iface[0] = '\0';
+    return false;
+}
+
+static bool getDefaultRouteIPv6(char iface[IF_NAMESIZE + 1], uint32_t* ifIndex, uint32_t* preferredSourceAddr)
+{
+    // TODO ipv6
+    return false;
+}
+
+bool ffNetifGetDefaultRouteImpl(char iface[IF_NAMESIZE + 1], uint32_t* ifIndex, uint32_t* preferredSourceAddr)
+{
+    if (getDefaultRouteIPv4(iface, ifIndex, preferredSourceAddr))
+        return true;
+
+    return getDefaultRouteIPv6(iface, ifIndex, preferredSourceAddr);
+}