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.length() == 0) continue;
59 if (s.endsWith("$")) s = s.substring(0, s.length() - 1);
60 if (s.endsWith(".class")) {
61 bcp.visitJavaClass(repo.loadClass(s.substring(0, s.length() - 6)));
63 JavaClass cl = repo.loadClass(s.substring(0, s.lastIndexOf('.')));;
64 bcp.visitJavaClass(cl);
66 Field[] fields = cl.getFields();
67 for(int j=0; j<fields.length; j++) {
68 if (fields[j].getName().equals(s.substring(s.lastIndexOf('.') + 1)))
69 bcp.visitJavaField(fields[j], cl);
72 } catch (Exception e) {
73 System.out.println("WARNING: couldn't load class for " + s);
78 System.out.println("\n\n======================================================================\n");
80 // we call start(), but the VM calls run()...
81 bcp.loadMethod("java.lang.Thread.run");
82 bcp.loadAllMethods("java.lang.SecurityContext");
83 bcp.loadAllMethods("java.lang.ThreadDeath");
84 bcp.loadMethod("java.lang.Thread.run"); // we call start(), but the VM calls run()...
85 bcp.loadMethod("java.lang.ref.Reference.enqueue"); // the GC calls this directly
86 bcp.loadAllMethods("gnu.gcj.runtime.StringBuffer"); // the compiler emits calls directly to this class
87 bcp.loadAllMethods("gnu.gcj.convert.Input_UTF8"); // retrieved via reflection
88 bcp.loadAllMethods("gnu.gcj.convert.Output_UTF8"); // retrieved via reflection
89 bcp.loadMethod("gnu.gcj.convert.BytesToUnicode.done"); // called by natString
90 bcp.loadAllStaticMethods("java.lang.reflect.Modifier"); // used all over natClass...
92 // the Interpreter.run() method's switchblock is too complex...
93 bcp.loadAllMethods("org.ibex.js.Interpreter$TryMarker");
94 bcp.loadAllMethods("org.ibex.js.Interpreter$CatchMarker");
95 bcp.loadAllMethods("org.ibex.js.Interpreter$LoopMarker");
96 bcp.loadAllMethods("org.ibex.js.Interpreter$FinallyData");
97 bcp.loadAllMethods("org.ibex.js.Interpreter$CallMarker");
98 bcp.loadAllMethods("org.ibex.js.Interpreter");
99 bcp.loadAllMethods("org.ibex.js.Interpreter$1");
100 bcp.loadAllMethods("org.ibex.js.Interpreter$Stub");
101 bcp.loadAllMethods("org.ibex.js.Trap$TrapScope");
102 bcp.loadMethod("org.ibex.js.JSScope.top");
103 bcp.loadAllMethods("org.ibex.Picture$1");
104 bcp.loadAllMethods("org.ibex.Ibex$Blessing");
105 bcp.loadAllMethods("org.ibex.util.SSL$entropySpinner");
106 bcp.loadAllMethods("org.ibex.HTTP$HTTPInputStream");
107 bcp.visitJavaClass(repo.loadClass("org.ibex.util.SSL"));
109 bcp.loadAllMethods("java.util.Hashtable$HashIterator");
110 bcp.loadMethod("java.util.SimpleTimeZone.useDaylightTime");
111 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FinalizerThread"));
112 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FirstThread"));
114 // to ensure we get all the stuff that might be called from CNI
115 bcp.loadAllMethods("org.ibex.plat.Linux");
116 bcp.loadAllMethods("org.ibex.plat.X11");
117 bcp.loadAllMethods("org.ibex.plat.GCJ");
118 bcp.loadAllMethods("org.ibex.plat.POSIX");
119 bcp.loadAllMethods("org.ibex.plat.X11$X11Surface");
120 bcp.loadAllMethods("org.ibex.plat.X11$X11PixelBuffer");
121 bcp.loadAllMethods("org.ibex.plat.X11$X11Picture");
122 bcp.loadAllMethods("org.ibex.Surface");
123 bcp.loadAllMethods("org.ibex.Picture");
124 bcp.loadAllMethods("org.ibex.PixelBuffer");
126 // primary entry point
127 bcp.loadMethod("org.ibex.plat.Linux.main");
128 System.out.println();
130 System.out.println("Dumping...");
131 ZipFile zf = new ZipFile(args[0]);
132 ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(args[0] + ".tmp"));
133 Enumeration e = zf.entries();
134 while(e.hasMoreElements()) {
135 ZipEntry ze = ((ZipEntry)e.nextElement());
136 String ss = ze.getName();
137 if (!ss.endsWith(".class")) continue;
138 ss = ss.substring(0, ss.length() - 6);
139 ss = ss.replace('/', '.');
140 dump(repo.loadClass(ss), zos);
144 new File(args[0] + ".tmp").renameTo(new File(args[0] + ".pruned"));
147 public static void dump(JavaClass clazz, ZipOutputStream zos) throws Exception {
148 if (!dest.contains(clazz)) return;
150 ConstantPoolGen newcpg = new ConstantPoolGen(clazz.getConstantPool());
151 ClassGen cg = new ClassGen(clazz);
152 InstructionFactory factory = new InstructionFactory(cg, newcpg);
155 cg.setConstantPool(newcpg);
157 boolean isconstructed = false;
158 Method[] methods = getMethods(clazz);
159 for(int i=0; i<methods.length; i++)
160 if (dest.contains(methods[i]) && methods[i].getName().equals("<init>"))
161 isconstructed = true;
163 // we can only prune static fields (to avoid altering object layout, which is hardcoded into
164 // CNI code), but that's okay since instance fields don't contribute to binary size
165 Field[] fields = clazz.getFields();
166 for(int i=0; i<fields.length; i++) {
167 if ((!dest.contains(fields[i]) && fields[i].isStatic()) ||
168 ((!(constructed.contains(clazz))) && !fields[i].isStatic())) {
169 System.out.println(" pruning field " + clazz.getClassName() + "." + fields[i].getName());
170 // FIXME this confuses gcj in jar-at-a-time mode
171 //cg.removeField(fields[i]);
176 boolean good = false;
177 for(int i=0; i<methods.length; i++) {
178 if (dest.contains(methods[i]) && (isconstructed || methods[i].isStatic())) {
181 if (methods[i].getCode() == null) {
182 System.out.println(" empty codeblock: " + clazz.getClassName() + "." + methods[i].getName());
184 System.out.println(" pruning " +(isconstructed?"":"unconstructed")+ " method " +
185 clazz.getClassName() + "." + methods[i].getName());
186 if (deleteMethods) { cg.removeMethod(methods[i]); continue; }
187 MethodGen mg = new MethodGen(methods[i], clazz.getClassName(), newcpg);
188 mg.removeExceptions();
189 InstructionList il = new InstructionList();
190 mg.setInstructionList(il);
191 InstructionHandle ih_0 = il.append(factory.createNew("java.lang.UnsatisfiedLinkError"));
192 il.append(InstructionConstants.DUP);
193 il.append(factory.createInvoke("java.lang.UnsatisfiedLinkError",
194 "<init>", Type.VOID, Type.NO_ARGS, Constants.INVOKESPECIAL));
195 il.append(InstructionConstants.ATHROW);
198 mg.removeExceptions();
199 mg.removeLocalVariables();
200 mg.removeExceptionHandlers();
201 mg.removeLineNumbers();
202 cg.replaceMethod(methods[i], mg.getMethod());
208 // FIXME: chain up to superclass' <clinit>... that might remove the need for this hack
209 // FIXME: gcj compiling in jar-at-a-time mode can't be convinced to let classes outside the jar override
210 // the ones inside the jar
213 if (!good && !clazz.isAbstract() && !clazz.isInterface()) {
214 System.out.println("DROPPING " + clazz.getClassName());
215 JavaClass[] ifaces = clazz.getInterfaces();
216 String[] ifacestrings = new String[ifaces.length];
217 for(int i=0; i<ifaces.length; i++) ifacestrings[i] = ifaces[i].getClassName();
218 cg = new ClassGen(clazz.getClassName(),
219 clazz.getSuperClass().getClassName(),
221 clazz.getAccessFlags(),
225 System.out.println("dumping " + clazz.getClassName());
227 FilterOutputStream noclose = new FilterOutputStream(zos) { public void close() throws IOException { flush(); } };
228 zos.putNextEntry(new ZipEntry(clazz.getClassName().replace('.', '/')+".class"));
229 cg.getJavaClass().dump(noclose);
233 public JavaClass sig2class(String sig) throws Exception {
234 if (sig == null) return null;
235 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
236 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
237 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
239 if (sig.length() <= 1) return null;
240 if (sig.equals("<null object>")) return null;
241 if (sig.startsWith("<return address")) return null;
242 return repo.loadClass(sig);
244 public void load(String sig) throws Exception {
245 if (sig == null) return;
246 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
247 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
248 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
250 if (sig.length() <= 1) return;
251 if (sig.equals("<null object>")) return;
252 if (sig.startsWith("<return address")) return;
253 visitJavaClass(repo.loadClass(sig));
255 public void load(Type t) throws Exception {
256 if (t == null) return;
257 if (t instanceof ArrayType) load(((ArrayType)t).getElementType());
258 if (!(t instanceof ObjectType)) return;
259 load(((ObjectType)t).getClassName());
262 public String getMethodSignature(Method m, ConstantPoolGen cpg) throws Exception { return m.getName() + m.getSignature(); }
263 public String getMethodSignature(InvokeInstruction ii, ConstantPoolGen cpg) throws Exception {
265 Type[] argtypes = ii.getArgumentTypes(cpg);
266 for(int j=0; j<argtypes.length; j++) sig += argtypes[j].getSignature();
267 return ii.getMethodName(cpg) + "(" + sig + ")" + ii.getReturnType(cpg).getSignature();
270 public void visitJavaMethod(JavaClass jc, Method method) throws Exception {
272 if (jc.getClassName().indexOf("SharedLib") != -1) return;
273 if (jc.getClassName().indexOf("Datagram") != -1) return;
274 if (jc.getClassName().startsWith("java.io.Object")) return;
275 if (jc.getClassName().startsWith("java.util.jar.")) return;
276 if (jc.getClassName().startsWith("java.net.Inet6")) return;
278 // gcj bug; gcj can't compile this method from a .class file input; I have no idea why
279 if (jc.getClassName().equals("java.lang.System") && method.getName().equals("runFinalizersOnExit")) return;
281 // we know these can't be constructed
282 if (method.getName().equals("<init>") && jc.getClassName().startsWith("java.lang.reflect.")) return;
284 if (dest.contains(method)) return;
287 if (method.getName().equals("<clinit>") && jc.getSuperClass() != null)
288 loadMethod(jc.getSuperClass().getClassName() + ".<clinit>");
290 if (method.isStatic() || method.getName().equals("<init>")) loadMethod(jc.getClassName() + ".<clinit>");
291 if (method.getName().equals("<init>")) {
292 // FIXME: generalize to all perinstancemethods
294 HashSet hs = (HashSet)uponconstruction.get(jc);
296 Iterator it = hs.iterator();
297 while(it.hasNext()) visitJavaMethod(jc, (Method)it.next());
299 loadMethod(jc.getClassName() + ".equals");
300 loadMethod(jc.getClassName() + ".hashCode");
301 loadMethod(jc.getClassName() + ".toString");
302 loadMethod(jc.getClassName() + ".finalize");
303 loadMethod(jc.getClassName() + ".clone");
306 ConstantPoolGen cpg = new ConstantPoolGen(method.getConstantPool());
307 if (!method.isStatic() && !constructed.contains(jc)) {
308 HashSet hs = (HashSet)uponconstruction.get(jc);
309 if (hs == null) uponconstruction.put(jc, hs = new HashSet());
311 markMethodInSubclasses(jc, method, cpg);
317 for(int i=0; i<level; i++) System.out.print(" ");
318 System.out.print(jc.getClassName() + "." + getMethodSignature(method, cpg));
319 markMethodInSubclasses(jc, method, cpg);
320 if (method.getCode() == null) { System.out.println(); level -= 2; return; }
321 byte[] code = method.getCode().getCode();
322 InstructionList il = new InstructionList(code);
323 InstructionHandle[] instructions = il.getInstructionHandles();
324 System.out.println(" [" + instructions.length + " instructions]");
325 for(int i=0; i<instructions.length; i++){
326 Instruction instr = instructions[i].getInstruction();;
327 if (instr instanceof Select) {
328 InstructionHandle[] ih2 = ((Select)instr).getTargets();
329 InstructionHandle[] ih3 = new InstructionHandle[instructions.length + ih2.length];
330 System.arraycopy(instructions, 0, ih3, 0, instructions.length);
331 System.arraycopy(ih2, 0, ih3, instructions.length, ih2.length);
334 if (instr instanceof LoadClass) {
335 ObjectType ot = (ObjectType)((LoadClass)instr).getLoadClassType(cpg);
336 if (ot != null) loadMethod(ot.getClassName() + ".<clinit>");
338 if (instr instanceof CPInstruction) load(((CPInstruction)instr).getType(cpg));
339 if (instr instanceof TypedInstruction) load(((TypedInstruction)instr).getType(cpg));
340 if (instr instanceof NEW) loadMethod(((NEW)instr).getLoadClassType(cpg).getClassName() + ".<init>");
341 if (instr instanceof org.apache.bcel.generic.FieldOrMethod)
342 load(((org.apache.bcel.generic.FieldOrMethod)instr).getClassType(cpg));
343 if (instr instanceof org.apache.bcel.generic.FieldInstruction) {
344 load(((org.apache.bcel.generic.FieldInstruction)instr).getFieldType(cpg));
345 load(((org.apache.bcel.generic.FieldInstruction)instr).getType(cpg));
346 String fieldName = ((org.apache.bcel.generic.FieldInstruction)instr).getFieldName(cpg);
347 JavaClass jc2 = repo.loadClass(((ObjectType)((org.apache.bcel.generic.FieldInstruction)instr).
348 getLoadClassType(cpg)).getClassName());
349 Field[] fields = jc2.getFields();
350 for(int j=0; j<fields.length; j++) if (fields[j].getName().equals(fieldName)) visitJavaField(fields[j], jc2);
352 if (instr instanceof InvokeInstruction) {
353 InvokeInstruction ii = (InvokeInstruction)instr;
354 String ii_sig = getMethodSignature(ii, cpg);
355 JavaClass c = sig2class(ii.getLoadClassType(cpg).getSignature());
357 load(ii.getType(cpg));
358 Method[] meths = getMethods(c);
359 boolean good = false;
360 for(int i2=0; i2<meths.length; i2++) {
361 if (getMethodSignature(meths[i2], cpg).equals(ii_sig)) {
362 visitJavaMethod(c, meths[i2]);
367 if (!good) throw new Exception("couldn't find method " + getMethodSignature(ii, cpg) + " in " + c.getClassName());
370 Type[] argtypes = method.getArgumentTypes();
371 for(int i=0; i<argtypes.length; i++) load(argtypes[i]);
372 if (method.getExceptionTable() != null) {
373 String[] exntypes = method.getExceptionTable().getExceptionNames();
374 for(int i=0; i<exntypes.length; i++) load(exntypes[i]);
379 public void visitJavaField(Field field, JavaClass clazz) throws Exception {
380 if (dest.contains(field)) return;
382 if (field.isStatic()) loadMethod(clazz.getClassName() + ".<clinit>");
385 public void visitJavaClass(JavaClass clazz) throws Exception {
386 if (dest.contains(clazz)) return;
389 ConstantPoolGen cpg = new ConstantPoolGen(clazz.getConstantPool());
391 for(int i=0; i<level; i++) System.out.print(" ");
392 System.out.println(clazz.getClassName() + ".class");
394 JavaClass superclass = clazz.getSuperClass();
395 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
396 if (subclasses.get(sup) == null) subclasses.put(sup, new HashSet());
397 ((HashSet)subclasses.get(sup)).add(clazz);
399 JavaClass[] interfaces = clazz.getAllInterfaces();
400 for(int i=0; i<interfaces.length; i++) {
401 if (subclasses.get(interfaces[i]) == null) subclasses.put(interfaces[i], new HashSet());
402 ((HashSet)subclasses.get(interfaces[i])).add(clazz);
405 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
407 remarkMethods(sup, clazz, cpg);
409 for(int i=0; i<interfaces.length; i++) {
410 visitJavaClass(interfaces[i]);
411 remarkMethods(interfaces[i], clazz, cpg);
414 Field[] fields = clazz.getFields();
415 for(int i=0; i<fields.length; i++) {
416 if (!fields[i].isStatic()) visitJavaField(fields[i], clazz);
418 Type t = fields[i].getType();
419 if (t instanceof ObjectType) load(t);
425 public void markMethodInSubclasses(JavaClass c, Method m, JavaClass subclass, ConstantPoolGen cpg) throws Exception {
426 if (m.isStatic()) return;
427 if (m.getName().equals("<init>")) return;
428 if (m.getName().equals("equals")) return;
429 if (m.getName().equals("hashCode")) return;
430 if (m.getName().equals("clone")) return;
431 if (m.getName().equals("finalize")) return;
432 if (m.getName().equals("toString")) return;
433 String sig = getMethodSignature(m, cpg);
434 Method[] submethods = getMethods(subclass);
435 for(int j=0; j<submethods.length; j++)
436 if (getMethodSignature(submethods[j], cpg).equals(sig))
437 visitJavaMethod(subclass, submethods[j]);
439 public void markMethodInSubclasses(JavaClass c, Method m, ConstantPoolGen cpg) throws Exception {
440 if (m.isStatic()) return;
441 if (m.getName().equals("<init>")) return;
442 HashSet s = (HashSet)subclasses.get(c);
443 if (s == null) return;
444 Object[] subclasses = s.toArray();
445 for(int i=0; i<subclasses.length; i++) {
446 JavaClass subclass = (JavaClass)subclasses[i];
447 if (subclass == c) continue;
448 markMethodInSubclasses(c, m, subclass, cpg);
452 public void remarkMethods(JavaClass c, ConstantPoolGen cpg) throws Exception {
453 Method[] meths =getMethods(c);
454 for(int j=0; j<meths.length; j++)
455 if (dest.contains(meths[j]) ||
456 (uponconstruction.get(c) != null && ((HashSet)uponconstruction.get(c)).contains(meths[j])))
457 markMethodInSubclasses(c, meths[j], cpg);
460 public void remarkMethods(JavaClass c, JavaClass target, ConstantPoolGen cpg) throws Exception {
461 Method[] meths = getMethods(c);
462 for(int j=0; j<meths.length; j++)
463 if (dest.contains(meths[j]) ||
464 (uponconstruction.get(c) != null && ((HashSet)uponconstruction.get(c)).contains(meths[j])))
465 markMethodInSubclasses(c, meths[j], target, cpg);
468 public static Hashtable methodsHashtable = new Hashtable();
469 public static Method[] getMethods(JavaClass c) {
470 Method[] ret = (Method[])methodsHashtable.get(c);
471 if (ret == null) methodsHashtable.put(c, ret = c.getMethods());