Clean up code

buildSrc/src/main/java/NativeRelocator.java

@@ -0,0 +1,169 @@
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+
+class NativeRelocator
+{
+	private static final Path rootDirectory = Path.of(System.getProperty("user.dir"), "relocate_natives");
+	private static final Path cacheRoot = rootDirectory.resolve("cache");
+	
+	
+	NativeRelocator() throws Exception
+	{
+		if (rootDirectory.resolve(".venv").toFile().exists())
+		{
+			return;
+		}
+		
+		ProcessBuilder processBuilder = new ProcessBuilder();
+		processBuilder.directory(rootDirectory.toFile());
+		
+		String os = System.getProperty("os.name").toLowerCase();
+		if (os.contains("win"))
+		{
+			processBuilder.command("powershell", "./prepare.ps1");
+		}
+		else if (os.contains("nix") || os.contains("nux") || os.contains("mac"))
+		{
+			processBuilder.command("./prepare.sh");
+		}
+		else
+		{
+			throw new IllegalStateException("Unsupported operating system: " + os);
+		}
+		
+		Process process = processBuilder.start();
+		CompletableFuture<Void> outputFuture = readOutputStreams(process);
+		
+		int exitCode = process.waitFor();
+		outputFuture.get();
+		
+		if (exitCode != 0)
+		{
+			throw new Exception("Prepare failed: " + exitCode);
+		}
+	}
+	
+	
+	private static CompletableFuture<Void> readOutputStreams(Process process)
+	{
+		return CompletableFuture.runAsync(() -> {
+			try
+			{
+				while (process.isAlive() || process.getInputStream().available() > 0 || process.getErrorStream().available() > 0)
+				{
+					if (process.getInputStream().available() > 0)
+					{
+						byte[] data = new byte[process.getInputStream().available()];
+						//noinspection ResultOfMethodCallIgnored
+						process.getInputStream().read(data);
+						System.out.write(data);
+					}
+					if (process.getErrorStream().available() > 0)
+					{
+						byte[] data = new byte[process.getErrorStream().available()];
+						//noinspection ResultOfMethodCallIgnored
+						process.getErrorStream().read(data);
+						System.err.write(data);
+					}
+					
+					//noinspection BusyWait
+					Thread.sleep(100);
+				}
+			}
+			catch (Throwable ignored)
+			{
+			}
+		});
+	}
+	
+	private void replaceInNullTerminatedStrings(byte[] byteArray, String target, String replacement)
+	{
+		if (target.length() < replacement.length())
+		{
+			throw new IllegalArgumentException("Replacement must be the same length or shorter than the target.");
+		}
+		
+		byte[] targetBytes = target.getBytes(StandardCharsets.US_ASCII);
+		byte[] replacementBytes = replacement.getBytes(StandardCharsets.US_ASCII);
+		
+		byte nullByte = 0;
+		
+		for (int endPos = 0; endPos < byteArray.length - targetBytes.length - 1; endPos++)
+		{
+			int startPos = endPos;
+			int targetPos = 0;
+			while (targetPos < targetBytes.length && byteArray[endPos] == targetBytes[targetPos])
+			{
+				targetPos++;
+				endPos++;
+			}
+			
+			if (targetPos == targetBytes.length)
+			{
+				System.arraycopy(replacementBytes, 0, byteArray, startPos, replacementBytes.length);
+				
+				startPos = startPos + replacementBytes.length;
+				while (byteArray[endPos] != nullByte)
+				{
+					byteArray[startPos] = byteArray[endPos];
+					endPos++;
+					startPos++;
+				}
+				byteArray[startPos] = nullByte;
+			}
+		}
+	}
+	
+	public byte[] fixModifiedBinary(Path outputFilePath, byte[] content) throws Exception
+	{
+		ProcessBuilder processBuilder = new ProcessBuilder();
+		processBuilder.directory(rootDirectory.toFile());
+		
+		processBuilder.command(
+				rootDirectory.resolve(".venv/Scripts").toFile().exists()
+						? rootDirectory.resolve(".venv/Scripts/python.exe").toString()
+						: rootDirectory.resolve(".venv/bin/python").toString(),
+				"./fix_modified_binary.py",
+				outputFilePath.toString()
+		);
+		
+		Process process = processBuilder.start();
+		CompletableFuture<Void> outputFuture = readOutputStreams(process);
+		
+		process.getOutputStream().write(content);
+		process.getOutputStream().close();
+		
+		int exitCode = process.waitFor();
+		outputFuture.get();
+		
+		if (exitCode != 0)
+		{
+			throw new Exception("Process failed: " + exitCode);
+		}
+		
+		return Files.readAllBytes(outputFilePath);
+	}
+	
+	public byte[] processBinary(String outputPath, byte[] content, Map<String, String> replacements) throws Exception
+	{
+		Path outputFilePath = cacheRoot.resolve(outputPath);
+		//noinspection ResultOfMethodCallIgnored
+		outputFilePath.getParent().toFile().mkdirs();
+		
+		if (outputFilePath.toFile().exists())
+		{
+			return Files.readAllBytes(outputFilePath);
+		}
+		
+		for (Map.Entry<String, String> replacement : replacements.entrySet())
+		{
+			this.replaceInNullTerminatedStrings(content, replacement.getKey(), replacement.getValue());
+		}
+		
+		return this.fixModifiedBinary(outputFilePath, content);
+	}
+	
+}