4 import java.util.zip.*;
5 import org.apache.bcel.*;
6 import org.apache.bcel.generic.*;
7 import org.apache.bcel.classfile.*;
8 import org.apache.bcel.util.*;
10 public class NanoGoat {
12 public static final boolean deleteMethods = false;
13 public static SyntheticRepository repo = null;
14 public static HashSet dest = new HashSet();
15 public static HashSet constructed = new HashSet();
16 public static String outdir = ".";
17 public static Hashtable subclasses = new Hashtable();
18 public static Hashtable uponconstruction = new Hashtable();
19 public static Hashtable mark_if_constructed = new Hashtable();
20 public static int level = 0;
24 public void loadAllMethods(String classname) throws Exception {
25 visitJavaClass(repo.loadClass(classname));
26 Method[] meths = getMethods(repo.loadClass(classname));
27 for(int i=0; i<meths.length; i++)
28 visitJavaMethod(repo.loadClass(classname), meths[i]);
31 public void loadAllStaticMethods(String classname) throws Exception {
32 visitJavaClass(repo.loadClass(classname));
33 Method[] meths = getMethods(repo.loadClass(classname));
34 for(int i=0; i<meths.length; i++)
35 if (meths[i].isStatic())
36 visitJavaMethod(repo.loadClass(classname), meths[i]);
39 public void loadMethod(String classAndMethodName) throws Exception {
40 String classname = classAndMethodName.substring(0, classAndMethodName.lastIndexOf('.'));
41 String methodname = classAndMethodName.substring(classAndMethodName.lastIndexOf('.') + 1);
42 if (classname.endsWith("." + methodname)) methodname = "<init>";
43 visitJavaClass(repo.loadClass(classname));
44 Method[] meths = getMethods(repo.loadClass(classname));
45 for(int i=0; i<meths.length; i++)
46 if (meths[i].getName().equals(methodname))
47 visitJavaMethod(repo.loadClass(classname), meths[i]);
49 public static void main(String[] args) throws Exception {
51 repo = SyntheticRepository.getInstance(new ClassPath(args[0]));
53 NanoGoat bcp = new NanoGoat();
54 BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
55 for(String s = br.readLine(); s != null; s = br.readLine()) {
57 if (s.endsWith(".class")) {
58 bcp.visitJavaClass(repo.loadClass(s.substring(0, s.length() - 6)));
60 JavaClass cl = repo.loadClass(s.substring(0, s.lastIndexOf('.')));;
61 bcp.visitJavaClass(cl);
63 Field[] fields = cl.getFields();
64 for(int j=0; j<fields.length; j++) {
65 if (fields[j].getName().equals(s.substring(s.lastIndexOf('.') + 1)))
66 bcp.visitJavaField(fields[j], cl);
69 } catch (Exception e) {
70 System.out.println("WARNING: couldn't load class for " + s);
75 System.out.println("\n\n======================================================================\n");
77 // we call start(), but the VM calls run()...
78 bcp.loadMethod("java.lang.Thread.run");
79 bcp.loadAllMethods("java.lang.SecurityContext");
80 bcp.loadAllMethods("java.lang.ThreadDeath");
81 bcp.loadMethod("java.lang.Thread.run"); // we call start(), but the VM calls run()...
82 bcp.loadMethod("java.lang.ref.Reference.enqueue"); // the GC calls this directly
83 bcp.loadAllMethods("gnu.gcj.runtime.StringBuffer"); // the compiler emits calls directly to this class
84 bcp.loadAllMethods("gnu.gcj.convert.Input_UTF8"); // retrieved via reflection
85 bcp.loadAllMethods("gnu.gcj.convert.Output_UTF8"); // retrieved via reflection
86 bcp.loadMethod("gnu.gcj.convert.BytesToUnicode.done"); // called by natString
87 bcp.loadAllStaticMethods("java.lang.reflect.Modifier"); // used all over natClass...
89 // the Interpreter.run() method's switchblock is too complex...
90 bcp.loadAllMethods("org.ibex.js.Interpreter$TryMarker");
91 bcp.loadAllMethods("org.ibex.js.Interpreter$CatchMarker");
92 bcp.loadAllMethods("org.ibex.js.Interpreter$LoopMarker");
93 bcp.loadAllMethods("org.ibex.js.Interpreter$FinallyData");
94 bcp.loadAllMethods("org.ibex.js.Interpreter$CallMarker");
95 bcp.loadAllMethods("org.ibex.js.Interpreter");
96 bcp.loadAllMethods("org.ibex.js.Interpreter$1");
97 bcp.loadAllMethods("org.ibex.js.Interpreter$Stub");
98 bcp.loadAllMethods("org.ibex.js.Trap$TrapScope");
99 bcp.loadMethod("org.ibex.js.JSScope.top");
100 bcp.loadAllMethods("org.ibex.Picture$1");
101 bcp.loadAllMethods("org.ibex.Ibex$Blessing");
102 bcp.loadAllMethods("org.ibex.util.SSL$entropySpinner");
103 bcp.loadAllMethods("org.ibex.HTTP$HTTPInputStream");
104 bcp.visitJavaClass(repo.loadClass("org.ibex.util.SSL"));
106 bcp.loadAllMethods("java.util.Hashtable$HashIterator");
107 bcp.loadMethod("java.util.SimpleTimeZone.useDaylightTime");
108 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FinalizerThread"));
109 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FirstThread"));
111 // to ensure we get all the stuff that might be called from CNI
112 bcp.loadAllMethods("org.ibex.plat.Linux");
113 bcp.loadAllMethods("org.ibex.plat.X11");
114 bcp.loadAllMethods("org.ibex.plat.GCJ");
115 bcp.loadAllMethods("org.ibex.plat.POSIX");
116 bcp.loadAllMethods("org.ibex.plat.X11$X11Surface");
117 bcp.loadAllMethods("org.ibex.plat.X11$X11PixelBuffer");
118 bcp.loadAllMethods("org.ibex.plat.X11$X11Picture");
119 bcp.loadAllMethods("org.ibex.Surface");
120 bcp.loadAllMethods("org.ibex.Picture");
121 bcp.loadAllMethods("org.ibex.PixelBuffer");
123 // primary entry point
124 bcp.loadMethod("org.ibex.plat.Linux.main");
125 System.out.println();
127 System.out.println("Dumping...");
128 ZipFile zf = new ZipFile(args[0]);
129 ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(args[0] + ".tmp"));
130 Enumeration e = zf.entries();
131 while(e.hasMoreElements()) {
132 ZipEntry ze = ((ZipEntry)e.nextElement());
133 String ss = ze.getName();
134 if (!ss.endsWith(".class")) continue;
135 ss = ss.substring(0, ss.length() - 6);
136 ss = ss.replace('/', '.');
137 dump(repo.loadClass(ss), zos);
141 new File(args[0] + ".tmp").renameTo(new File(args[0] + ".pruned"));
144 public static void dump(JavaClass clazz, ZipOutputStream zos) throws Exception {
145 if (!dest.contains(clazz)) return;
147 ConstantPoolGen newcpg = new ConstantPoolGen(clazz.getConstantPool());
148 ClassGen cg = new ClassGen(clazz);
149 InstructionFactory factory = new InstructionFactory(cg, newcpg);
152 cg.setConstantPool(newcpg);
154 boolean isconstructed = false;
155 Method[] methods = getMethods(clazz);
156 for(int i=0; i<methods.length; i++)
157 if (dest.contains(methods[i]) && methods[i].getName().equals("<init>"))
158 isconstructed = true;
160 // we can only prune static fields (to avoid altering object layout, which is hardcoded into
161 // CNI code), but that's okay since instance fields don't contribute to binary size
162 Field[] fields = clazz.getFields();
163 for(int i=0; i<fields.length; i++) {
164 if ((!dest.contains(fields[i]) && fields[i].isStatic()) ||
165 ((!(constructed.contains(clazz))) && !fields[i].isStatic())) {
166 System.out.println(" pruning field " + clazz.getClassName() + "." + fields[i].getName());
167 // FIXME this confuses gcj in jar-at-a-time mode
168 //cg.removeField(fields[i]);
173 boolean good = false;
174 for(int i=0; i<methods.length; i++) {
175 if (dest.contains(methods[i]) && (isconstructed || methods[i].isStatic())) {
178 if (methods[i].getCode() == null) {
179 System.out.println(" empty codeblock: " + clazz.getClassName() + "." + methods[i].getName());
181 System.out.println(" pruning " +(isconstructed?"":"unconstructed")+ " method " +
182 clazz.getClassName() + "." + methods[i].getName());
183 if (deleteMethods) { cg.removeMethod(methods[i]); continue; }
184 MethodGen mg = new MethodGen(methods[i], clazz.getClassName(), newcpg);
185 mg.removeExceptions();
186 InstructionList il = new InstructionList();
187 mg.setInstructionList(il);
188 InstructionHandle ih_0 = il.append(factory.createNew("java.lang.UnsatisfiedLinkError"));
189 il.append(InstructionConstants.DUP);
190 il.append(factory.createInvoke("java.lang.UnsatisfiedLinkError",
191 "<init>", Type.VOID, Type.NO_ARGS, Constants.INVOKESPECIAL));
192 il.append(InstructionConstants.ATHROW);
195 mg.removeExceptions();
196 mg.removeLocalVariables();
197 mg.removeExceptionHandlers();
198 mg.removeLineNumbers();
199 cg.replaceMethod(methods[i], mg.getMethod());
205 // FIXME: chain up to superclass' <clinit>... that might remove the need for this hack
206 // FIXME: gcj compiling in jar-at-a-time mode can't be convinced to let classes outside the jar override
207 // the ones inside the jar
210 if (!good && !clazz.isAbstract() && !clazz.isInterface()) {
211 System.out.println("DROPPING " + clazz.getClassName());
212 JavaClass[] ifaces = clazz.getInterfaces();
213 String[] ifacestrings = new String[ifaces.length];
214 for(int i=0; i<ifaces.length; i++) ifacestrings[i] = ifaces[i].getClassName();
215 cg = new ClassGen(clazz.getClassName(),
216 clazz.getSuperClass().getClassName(),
218 clazz.getAccessFlags(),
222 System.out.println("dumping " + clazz.getClassName());
224 FilterOutputStream noclose = new FilterOutputStream(zos) { public void close() throws IOException { flush(); } };
225 zos.putNextEntry(new ZipEntry(clazz.getClassName().replace('.', '/')+".class"));
226 cg.getJavaClass().dump(noclose);
230 public JavaClass sig2class(String sig) throws Exception {
231 if (sig == null) return null;
232 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
233 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
234 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
236 if (sig.length() <= 1) return null;
237 if (sig.equals("<null object>")) return null;
238 if (sig.startsWith("<return address")) return null;
239 return repo.loadClass(sig);
241 public void load(String sig) throws Exception {
242 if (sig == null) return;
243 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
244 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
245 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
247 if (sig.length() <= 1) return;
248 if (sig.equals("<null object>")) return;
249 if (sig.startsWith("<return address")) return;
250 visitJavaClass(repo.loadClass(sig));
252 public void load(Type t) throws Exception {
253 if (t == null) return;
254 if (t instanceof ArrayType) load(((ArrayType)t).getElementType());
255 if (!(t instanceof ObjectType)) return;
256 load(((ObjectType)t).getClassName());
259 public String getMethodSignature(Method m, ConstantPoolGen cpg) throws Exception { return m.getName() + m.getSignature(); }
260 public String getMethodSignature(InvokeInstruction ii, ConstantPoolGen cpg) throws Exception {
262 Type[] argtypes = ii.getArgumentTypes(cpg);
263 for(int j=0; j<argtypes.length; j++) sig += argtypes[j].getSignature();
264 return ii.getMethodName(cpg) + "(" + sig + ")" + ii.getReturnType(cpg).getSignature();
267 public void visitJavaMethod(JavaClass jc, Method method) throws Exception {
269 if (jc.getClassName().indexOf("SharedLib") != -1) return;
270 if (jc.getClassName().indexOf("Datagram") != -1) return;
271 if (jc.getClassName().startsWith("java.io.Object")) return;
272 if (jc.getClassName().startsWith("java.util.jar.")) return;
273 if (jc.getClassName().startsWith("java.net.Inet6")) return;
275 // gcj bug; gcj can't compile this method from a .class file input; I have no idea why
276 if (jc.getClassName().equals("java.lang.System") && method.getName().equals("runFinalizersOnExit")) return;
278 // we know these can't be constructed
279 if (method.getName().equals("<init>") && jc.getClassName().startsWith("java.lang.reflect.")) return;
281 if (dest.contains(method)) return;
284 if (method.getName().equals("<clinit>") && jc.getSuperClass() != null)
285 loadMethod(jc.getSuperClass().getClassName() + ".<clinit>");
287 if (method.isStatic() || method.getName().equals("<init>")) loadMethod(jc.getClassName() + ".<clinit>");
288 if (method.getName().equals("<init>")) {
289 // FIXME: generalize to all perinstancemethods
291 HashSet hs = (HashSet)uponconstruction.get(jc);
293 Iterator it = hs.iterator();
294 while(it.hasNext()) visitJavaMethod(jc, (Method)it.next());
296 loadMethod(jc.getClassName() + ".equals");
297 loadMethod(jc.getClassName() + ".hashCode");
298 loadMethod(jc.getClassName() + ".toString");
299 loadMethod(jc.getClassName() + ".finalize");
300 loadMethod(jc.getClassName() + ".clone");
303 ConstantPoolGen cpg = new ConstantPoolGen(method.getConstantPool());
304 if (!method.isStatic() && !constructed.contains(jc)) {
305 HashSet hs = (HashSet)uponconstruction.get(jc);
306 if (hs == null) uponconstruction.put(jc, hs = new HashSet());
308 markMethodInSubclasses(jc, method, cpg);
314 for(int i=0; i<level; i++) System.out.print(" ");
315 System.out.print(jc.getClassName() + "." + getMethodSignature(method, cpg));
316 markMethodInSubclasses(jc, method, cpg);
317 if (method.getCode() == null) { System.out.println(); level -= 2; return; }
318 byte[] code = method.getCode().getCode();
319 InstructionList il = new InstructionList(code);
320 InstructionHandle[] instructions = il.getInstructionHandles();
321 System.out.println(" [" + instructions.length + " instructions]");
322 for(int i=0; i<instructions.length; i++){
323 Instruction instr = instructions[i].getInstruction();;
324 if (instr instanceof Select) {
325 InstructionHandle[] ih2 = ((Select)instr).getTargets();
326 InstructionHandle[] ih3 = new InstructionHandle[instructions.length + ih2.length];
327 System.arraycopy(instructions, 0, ih3, 0, instructions.length);
328 System.arraycopy(ih2, 0, ih3, instructions.length, ih2.length);
331 if (instr instanceof LoadClass) {
332 ObjectType ot = (ObjectType)((LoadClass)instr).getLoadClassType(cpg);
333 if (ot != null) loadMethod(ot.getClassName() + ".<clinit>");
335 if (instr instanceof CPInstruction) load(((CPInstruction)instr).getType(cpg));
336 if (instr instanceof TypedInstruction) load(((TypedInstruction)instr).getType(cpg));
337 if (instr instanceof NEW) loadMethod(((NEW)instr).getLoadClassType(cpg).getClassName() + ".<init>");
338 if (instr instanceof org.apache.bcel.generic.FieldOrMethod)
339 load(((org.apache.bcel.generic.FieldOrMethod)instr).getClassType(cpg));
340 if (instr instanceof org.apache.bcel.generic.FieldInstruction) {
341 load(((org.apache.bcel.generic.FieldInstruction)instr).getFieldType(cpg));
342 load(((org.apache.bcel.generic.FieldInstruction)instr).getType(cpg));
343 String fieldName = ((org.apache.bcel.generic.FieldInstruction)instr).getFieldName(cpg);
344 JavaClass jc2 = repo.loadClass(((ObjectType)((org.apache.bcel.generic.FieldInstruction)instr).
345 getLoadClassType(cpg)).getClassName());
346 Field[] fields = jc2.getFields();
347 for(int j=0; j<fields.length; j++) if (fields[j].getName().equals(fieldName)) visitJavaField(fields[j], jc2);
349 if (instr instanceof InvokeInstruction) {
350 InvokeInstruction ii = (InvokeInstruction)instr;
351 String ii_sig = getMethodSignature(ii, cpg);
352 JavaClass c = sig2class(ii.getLoadClassType(cpg).getSignature());
354 load(ii.getType(cpg));
355 Method[] meths = getMethods(c);
356 boolean good = false;
357 for(int i2=0; i2<meths.length; i2++) {
358 if (getMethodSignature(meths[i2], cpg).equals(ii_sig)) {
359 visitJavaMethod(c, meths[i2]);
364 if (!good) throw new Exception("couldn't find method " + getMethodSignature(ii, cpg) + " in " + c.getClassName());
367 Type[] argtypes = method.getArgumentTypes();
368 for(int i=0; i<argtypes.length; i++) load(argtypes[i]);
369 if (method.getExceptionTable() != null) {
370 String[] exntypes = method.getExceptionTable().getExceptionNames();
371 for(int i=0; i<exntypes.length; i++) load(exntypes[i]);
376 public void visitJavaField(Field field, JavaClass clazz) throws Exception {
377 if (dest.contains(field)) return;
379 if (field.isStatic()) loadMethod(clazz.getClassName() + ".<clinit>");
382 public void visitJavaClass(JavaClass clazz) throws Exception {
383 if (dest.contains(clazz)) return;
386 ConstantPoolGen cpg = new ConstantPoolGen(clazz.getConstantPool());
388 for(int i=0; i<level; i++) System.out.print(" ");
389 System.out.println(clazz.getClassName() + ".class");
391 JavaClass superclass = clazz.getSuperClass();
392 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
393 if (subclasses.get(sup) == null) subclasses.put(sup, new HashSet());
394 ((HashSet)subclasses.get(sup)).add(clazz);
396 JavaClass[] interfaces = clazz.getAllInterfaces();
397 for(int i=0; i<interfaces.length; i++) {
398 if (subclasses.get(interfaces[i]) == null) subclasses.put(interfaces[i], new HashSet());
399 ((HashSet)subclasses.get(interfaces[i])).add(clazz);
402 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
404 remarkMethods(sup, clazz, cpg);
406 for(int i=0; i<interfaces.length; i++) {
407 visitJavaClass(interfaces[i]);
408 remarkMethods(interfaces[i], clazz, cpg);
411 Field[] fields = clazz.getFields();
412 for(int i=0; i<fields.length; i++) {
413 if (!fields[i].isStatic()) visitJavaField(fields[i], clazz);
415 Type t = fields[i].getType();
416 if (t instanceof ObjectType) load(t);
422 public void markMethodInSubclasses(JavaClass c, Method m, JavaClass subclass, ConstantPoolGen cpg) throws Exception {
423 if (m.isStatic()) return;
424 if (m.getName().equals("<init>")) return;
425 if (m.getName().equals("equals")) return;
426 if (m.getName().equals("hashCode")) return;
427 if (m.getName().equals("clone")) return;
428 if (m.getName().equals("finalize")) return;
429 if (m.getName().equals("toString")) return;
430 String sig = getMethodSignature(m, cpg);
431 Method[] submethods = getMethods(subclass);
432 for(int j=0; j<submethods.length; j++)
433 if (getMethodSignature(submethods[j], cpg).equals(sig))
434 visitJavaMethod(subclass, submethods[j]);
436 public void markMethodInSubclasses(JavaClass c, Method m, ConstantPoolGen cpg) throws Exception {
437 if (m.isStatic()) return;
438 if (m.getName().equals("<init>")) return;
439 HashSet s = (HashSet)subclasses.get(c);
440 if (s == null) return;
441 Object[] subclasses = s.toArray();
442 for(int i=0; i<subclasses.length; i++) {
443 JavaClass subclass = (JavaClass)subclasses[i];
444 if (subclass == c) continue;
445 markMethodInSubclasses(c, m, subclass, cpg);
449 public void remarkMethods(JavaClass c, ConstantPoolGen cpg) throws Exception {
450 Method[] meths =getMethods(c);
451 for(int j=0; j<meths.length; j++)
452 if (dest.contains(meths[j]) ||
453 (uponconstruction.get(c) != null && ((HashSet)uponconstruction.get(c)).contains(meths[j])))
454 markMethodInSubclasses(c, meths[j], cpg);
457 public void remarkMethods(JavaClass c, JavaClass target, ConstantPoolGen cpg) throws Exception {
458 Method[] meths = getMethods(c);
459 for(int j=0; j<meths.length; j++)
460 if (dest.contains(meths[j]) ||
461 (uponconstruction.get(c) != null && ((HashSet)uponconstruction.get(c)).contains(meths[j])))
462 markMethodInSubclasses(c, meths[j], target, cpg);
465 public static Hashtable methodsHashtable = new Hashtable();
466 public static Method[] getMethods(JavaClass c) {
467 Method[] ret = (Method[])methodsHashtable.get(c);
468 if (ret == null) methodsHashtable.put(c, ret = c.getMethods());