WIP: macos support

bramble-java/src/main/java/org/briarproject/bramble/plugin/tor/UnixTorPlugin.java

@@ -53,7 +53,7 @@ class UnixTorPlugin extends JavaTorPlugin {
 
 	private interface CLibrary extends Library {
 
-		CLibrary INSTANCE = Native.loadLibrary("c", CLibrary.class);
+		CLibrary INSTANCE = Native.load("c", CLibrary.class);
 
 		int getpid();
 	}

bramble-java/src/main/java/org/briarproject/bramble/plugin/tor/UnixTorPluginFactory.java

@@ -27,6 +27,7 @@ import javax.net.SocketFactory;
 
 import static java.util.logging.Level.INFO;
 import static org.briarproject.bramble.util.OsUtils.isLinux;
+import static org.briarproject.bramble.util.OsUtils.isMac;
 
 @Immutable
 @NotNullByDefault
@@ -57,14 +58,18 @@ public class UnixTorPluginFactory extends TorPluginFactory {
 	@Nullable
 	@Override
 	String getArchitectureForTorBinary() {
-		if (!isLinux()) return null;
+		if (!isLinux() && !isMac()) return null;
 		String arch = System.getProperty("os.arch");
 		if (LOG.isLoggable(INFO)) {
 			LOG.info("System's os.arch is " + arch);
 		}
-		if (arch.equals("amd64")) return "x86_64";
-		else if (arch.equals("aarch64")) return "aarch64";
-		else if (arch.equals("arm")) return "armhf";
+		if (isLinux()) {
+			if (arch.equals("amd64")) return "x86_64";
+			else if (arch.equals("aarch64")) return "aarch64";
+			else if (arch.equals("arm")) return "armhf";
+		} else if (isMac()) {
+			if (arch.equals("aarch64")) return "aarch64";
+		}
 		return null;
 	}