Merge remote-tracking branch 'origin/asm-util' into dev

src/main/java/com/gtnewhorizon/gtnhlib/asm/ASMUtil.java

@@ -0,0 +1,165 @@
+package com.gtnewhorizon.gtnhlib.asm;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintWriter;
+import java.nio.file.Files;
+
+import net.minecraft.launchwrapper.Launch;
+
+import org.apache.commons.io.FileUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.util.ASMifier;
+import org.objectweb.asm.util.Textifier;
+import org.objectweb.asm.util.TraceClassVisitor;
+
+public class ASMUtil {
+
+    private static final Logger logger = LogManager.getLogger("ASMUtil - GTNHLib");
+    private static File outputDir = null;
+
+    private static void emptyClassOutputFolder() {
+        outputDir = new File(Launch.minecraftHome, "ASM_GTNH");
+        try {
+            FileUtils.deleteDirectory(outputDir);
+        } catch (IOException ignored) {}
+        if (!outputDir.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            outputDir.mkdirs();
+        }
+    }
+
+    public static void saveClassToDisk(Class<?> clazz) {
+        try (InputStream is = clazz.getResourceAsStream('/' + clazz.getName().replace('.', '/') + ".class")) {
+            final byte[] bytes = getClassBytes(is);
+            ASMUtil.saveTransformedClass(bytes, clazz.getName());
+        } catch (IOException e) {
+            logger.error("Couldn't load bytes of " + clazz.getName(), e);
+        }
+    }
+
+    private static byte[] getClassBytes(InputStream is) throws IOException {
+        if (is == null) {
+            throw new IOException("Class not found");
+        }
+        byte[] b = new byte[is.available()];
+        int len = 0;
+        while (true) {
+            int n = is.read(b, len, b.length - len);
+            if (n == -1) {
+                if (len < b.length) {
+                    byte[] c = new byte[len];
+                    System.arraycopy(b, 0, c, 0, len);
+                    b = c;
+                }
+                return b;
+            }
+            len += n;
+            if (len == b.length) {
+                int last = is.read();
+                if (last < 0) {
+                    return b;
+                }
+                byte[] c = new byte[b.length + 1000];
+                System.arraycopy(b, 0, c, 0, len);
+                c[len++] = (byte) last;
+                b = c;
+            }
+        }
+    }
+
+    public static void saveTransformedClass(final byte[] classBytes, final String transformedName) {
+        final String fileName = transformedName.replace('.', File.separatorChar);
+        saveAsRawClassFile(classBytes, transformedName, fileName);
+        saveAsBytecodeFile(classBytes, transformedName, fileName);
+        saveAsASMFile(classBytes, transformedName, fileName);
+    }
+
+    public static void saveAsRawClassFile(byte[] classBytes, String transformedName) {
+        final String fileName = transformedName.replace('.', File.separatorChar);
+        ASMUtil.saveAsRawClassFile(classBytes, transformedName, fileName);
+    }
+
+    public static void saveAsRawClassFile(byte[] classBytes, String transformedName, String fileName) {
+        if (outputDir == null) {
+            emptyClassOutputFolder();
+        }
+        final File classFile = new File(outputDir, fileName + ".class");
+        final File outDir = classFile.getParentFile();
+        if (!outDir.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            outDir.mkdirs();
+        }
+        if (classFile.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            classFile.delete();
+        }
+        try (final OutputStream output = Files.newOutputStream(classFile.toPath())) {
+            output.write(classBytes);
+            logger.info("Saved class (byte[]) to " + classFile.toPath());
+        } catch (IOException e) {
+            logger.error("Could not save class (byte[]) " + transformedName, e);
+        }
+    }
+
+    public static void saveAsBytecodeFile(byte[] classBytes, String transformedName) {
+        final String fileName = transformedName.replace('.', File.separatorChar);
+        ASMUtil.saveAsBytecodeFile(classBytes, transformedName, fileName);
+    }
+
+    public static void saveAsBytecodeFile(byte[] data, String transformedName, String fileName) {
+        if (outputDir == null) {
+            emptyClassOutputFolder();
+        }
+        final File bytecodeFile = new File(outputDir, fileName + "_BYTECODE.txt");
+        final File outDir = bytecodeFile.getParentFile();
+        if (!outDir.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            outDir.mkdirs();
+        }
+        if (bytecodeFile.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            bytecodeFile.delete();
+        }
+        try (final OutputStream output = Files.newOutputStream(bytecodeFile.toPath())) {
+            final ClassReader classReader = new ClassReader(data);
+            classReader.accept(new TraceClassVisitor(null, new Textifier(), new PrintWriter(output)), 0);
+            logger.info("Saved class (bytecode) to " + bytecodeFile.toPath());
+        } catch (IOException e) {
+            logger.error("Could not save class (bytecode) " + transformedName, e);
+        }
+    }
+
+    public static void saveAsASMFile(byte[] classBytes, String transformedName) {
+        final String fileName = transformedName.replace('.', File.separatorChar);
+        ASMUtil.saveAsASMFile(classBytes, transformedName, fileName);
+    }
+
+    public static void saveAsASMFile(byte[] data, String transformedName, String fileName) {
+        if (outputDir == null) {
+            emptyClassOutputFolder();
+        }
+        final File asmifiedFile = new File(outputDir, fileName + "_ASM.txt");
+        final File outDir = asmifiedFile.getParentFile();
+        if (!outDir.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            outDir.mkdirs();
+        }
+        if (asmifiedFile.exists()) {
+            // noinspection ResultOfMethodCallIgnored
+            asmifiedFile.delete();
+        }
+        try (final OutputStream output = Files.newOutputStream(asmifiedFile.toPath())) {
+            final ClassReader classReader = new ClassReader(data);
+            classReader.accept(new TraceClassVisitor(null, new ASMifier(), new PrintWriter(output)), 0);
+            logger.info("Saved class (ASMified) to " + asmifiedFile.toPath());
+        } catch (IOException e) {
+            logger.error("Could not save class (ASMified) " + transformedName, e);
+        }
+    }
+
+}