Write a better native library loader so DLLs are no longer extracted to the current directory on Windows.

src/com/limelight/binding/LibraryHelper.java

@@ -0,0 +1,85 @@
+package com.limelight.binding;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.HashSet;
+
+public class LibraryHelper {
+	private static final HashSet<String> avcDependencies = new HashSet<String>();
+	private static final boolean needsDependencyExtraction;
+	private static final String libraryExtractionFolder;
+	
+	static {
+		needsDependencyExtraction = System.getProperty("os.name", "").contains("Windows");
+		libraryExtractionFolder = System.getProperty("java.io.tmpdir", ".");
+		
+		// FFMPEG libraries
+		avcDependencies.add("avutil-52");
+		avcDependencies.add("swresample-0");
+		avcDependencies.add("swscale-2");
+		avcDependencies.add("avcodec-55");
+		avcDependencies.add("avformat-55");
+		avcDependencies.add("avfilter-3");
+		
+		// The AVC JNI library itself
+		avcDependencies.add("nv_avc_dec");
+		
+		// Additional Windows dependencies
+		if (System.getProperty("os.name").contains("Windows")) {
+			avcDependencies.add("postproc-52");
+			avcDependencies.add("pthreadVC2");
+		}
+	}
+	
+	public static void loadNativeLibrary(String libraryName) {
+		if (needsDependencyExtraction && avcDependencies.contains(libraryName)) {
+			System.load(libraryExtractionFolder + File.separatorChar + System.mapLibraryName(libraryName));
+		}
+		else {
+			System.loadLibrary(libraryName);
+		}
+	}
+
+	public static void prepareNativeLibraries() throws IOException {
+		if (!needsDependencyExtraction) {
+			return;
+		}
+		
+		for (String dependency : avcDependencies) {
+			extractNativeLibrary(dependency);
+		}
+	}
+	
+	private static void extractNativeLibrary(String libraryName) throws IOException {
+		// convert general library name to platform-specific name
+		libraryName = System.mapLibraryName(libraryName);
+		
+		InputStream resource = new Object().getClass().getResourceAsStream("/binlib/"+libraryName);
+		if (resource == null) {
+			throw new FileNotFoundException("Unable to find native library in JAR: "+libraryName);
+		}
+		File destination = new File(libraryExtractionFolder+File.separatorChar+libraryName);
+		
+		// this will only delete it if it exists, and then create a new file
+		destination.delete();
+		destination.createNewFile();
+		
+		//this is the janky java 6 way to copy a file
+		FileOutputStream fos = null;
+		try {
+			fos = new FileOutputStream(destination);
+			int read;
+			byte[] readBuffer = new byte[16384];
+			while ((read = resource.read(readBuffer)) != -1) {
+				fos.write(readBuffer, 0, read);
+			}
+		} finally {
+			if (fos != null) {
+				fos.close();
+			}
+		}
+	}
+}