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.*;
11 public class BytecodePruner {
13 public static final boolean deleteMethods = false;
16 public static SyntheticRepository repo = null;
18 public static HashSet dest = new HashSet();
20 public static String outdir = ".";
22 public void loadAllMethods(String classname) throws Exception {
23 visitJavaClass(repo.loadClass(classname));
24 Method[] meths = getMethods(repo.loadClass(classname));
25 for(int i=0; i<meths.length; i++) visitJavaMethod(repo.loadClass(classname), meths[i]);
28 public void loadField(String classAndMethodName) throws Exception {
29 String classname = classAndMethodName.substring(0, classAndMethodName.lastIndexOf('.'));
30 String methodname = classAndMethodName.substring(classAndMethodName.lastIndexOf('.') + 1);
31 visitJavaClass(repo.loadClass(classname));
32 Field[] meths = repo.loadClass(classname).getFields();
33 for(int i=0; i<meths.length; i++)
34 if (meths[i].getName().equals(methodname))
35 visitJavaField(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 visitJavaClass(repo.loadClass(classname));
43 Method[] meths = getMethods(repo.loadClass(classname));
44 for(int i=0; i<meths.length; i++)
45 if (meths[i].getName().equals(methodname))
46 visitJavaMethod(repo.loadClass(classname), meths[i]);
48 public static void main(String[] s) throws Exception {
50 if (s.length >= 3 && s[1].equals("-o")) { outdir = s[2]; start += 2; }
51 repo = SyntheticRepository.getInstance(new ClassPath(s[0]));
53 BytecodePruner bcp = new BytecodePruner();
54 for(int i=start; i<s.length; i++) {
56 if (s[i].endsWith(".class")) {
57 bcp.visitJavaClass(repo.loadClass(s[i].substring(0, s[i].length() - 6)));
59 JavaClass cl = repo.loadClass(s[i].substring(0, s[i].lastIndexOf('.')));;
60 bcp.visitJavaClass(cl);
61 Method[] meths = getMethods(cl);
62 for(int j=0; j<meths.length; j++) {
63 if (meths[j].getName().equals(s[i].substring(s[i].lastIndexOf('.') + 1)))
64 bcp.visitJavaMethod(cl, meths[j]);
67 } catch (Exception e) {
68 System.out.println("WARNING: couldn't load class for " + s[i]);
72 System.out.println("\n\n======================================================================\n");
74 // we call start(), but the VM calls run()...
75 bcp.loadMethod("java.lang.Thread.run");
76 bcp.loadAllMethods("java.lang.SecurityContext");
77 bcp.visitJavaClass(repo.loadClass("java.awt.AWTPermission"));
78 bcp.visitJavaClass(repo.loadClass("gnu.classpath.Configuration"));
79 bcp.loadAllMethods("java.lang.ThreadDeath");
81 bcp.loadAllMethods("java.util.Hashtable$HashIterator");
82 bcp.loadMethod("java.util.SimpleTimeZone.useDaylightTime");
83 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FinalizerThread"));
84 bcp.visitJavaClass(repo.loadClass("gnu.gcj.runtime.FirstThread"));
87 bcp.loadAllMethods("gnu.gcj.protocol.http.Handler");
88 bcp.loadAllMethods("gnu.gcj.protocol.file.Handler");
89 bcp.loadAllMethods("gnu.gcj.protocol.core.Handler");
90 bcp.loadAllMethods("gnu.gcj.protocol.jar.Handler");
91 bcp.loadAllMethods("gnu.gcj.convert.Input_UTF8"); // retrieved via reflection
92 bcp.loadAllMethods("gnu.gcj.convert.Output_UTF8"); // retrieved via reflection
93 bcp.loadAllMethods("gnu.gcj.convert.Input_8859_1"); // retrieved via reflection
94 bcp.loadAllMethods("gnu.gcj.convert.Output_8859_1"); // retrieved via reflection
95 bcp.loadAllMethods("gnu.gcj.convert.Input_ASCII"); // retrieved via reflection
96 bcp.loadAllMethods("gnu.gcj.convert.Output_ASCII"); // retrieved via reflection
97 bcp.loadMethod("java.lang.Thread.run"); // we call start(), but the VM calls run()...
98 bcp.loadMethod("java.lang.ref.Reference.enqueue"); // the GC calls this directly
99 bcp.loadAllMethods("gnu.gcj.runtime.StringBuffer"); // the compiler emits calls directly to this class
101 // often called from native subclasses....
103 bcp.loadAllMethods("org.ibex.Surface");
104 bcp.loadAllMethods("org.ibex.Template$TemplateHelper$1");
105 bcp.loadAllMethods("org.ibex.Surface$DoubleBufferedSurface");
106 bcp.loadAllMethods("org.ibex.Surface$3");
107 bcp.loadAllMethods("org.ibex.Surface$2");
108 bcp.loadAllMethods("org.ibex.Picture");
109 bcp.loadAllMethods("org.ibex.PixelBuffer");
110 bcp.loadAllMethods("org.ibex.Platform");
111 bcp.loadAllMethods("org.ibex.Scheduler");
112 bcp.loadAllMethods("org.ibex.plat.X11");
113 bcp.loadAllMethods("org.ibex.plat.X11$X11Picture");
114 bcp.loadAllMethods("org.ibex.plat.X11$X11PixelBuffer");
115 bcp.loadAllMethods("org.ibex.plat.X11$X11Surface");
116 bcp.loadAllMethods("org.ibex.XMLRPC");
117 bcp.loadAllMethods("java.util.Date");
118 bcp.loadAllMethods("java.text.DateFormat");
119 bcp.loadAllMethods("java.text.NumberFormat");
121 Method[] meths = getMethods(repo.loadClass("org.ibex.plat.Linux"));
122 for(int i=0; i<meths.length; i++) {
123 if (meths[i].getName().equals("main"))
124 bcp.visitJavaMethod(repo.loadClass("org.ibex.plat.Linux"), meths[i]);
126 System.out.println();
128 System.out.println("Dumping...");
130 StringTokenizer st = new StringTokenizer(s[0], ":");
131 while(st.hasMoreTokens()) {
132 ZipFile zf = new ZipFile(st.nextToken());
133 Enumeration e = zf.entries();
134 while(e.hasMoreElements()) {
135 String ss = ((ZipEntry)e.nextElement()).getName();
136 if (!ss.endsWith(".class")) continue;
137 ss = ss.substring(0, ss.length() - 6);
138 ss = ss.replace('/', '.');
139 dump(repo.loadClass(ss));
144 public BytecodePruner() { }
146 public static void dump(JavaClass clazz) throws Exception {
147 if (!dest.contains(clazz)) return;
149 ConstantPoolGen newcpg = new ConstantPoolGen(clazz.getConstantPool());
150 ClassGen cg = new ClassGen(clazz);
151 InstructionFactory factory = new InstructionFactory(cg, newcpg);
154 cg.setConstantPool(newcpg);
155 Field[] fields = clazz.getFields();
156 for(int i=0; i<fields.length; i++)
157 if (!dest.contains(fields[i]) && false) {
158 System.out.println(" pruning " + clazz.getClassName() + "." + fields[i].getName());
159 cg.removeField(fields[i]);
162 Method[] methods = getMethods(clazz);
164 boolean good = false;
165 for(int i=0; i<methods.length; i++) {
166 if (dest.contains(methods[i]) ||
167 clazz.getClassName().startsWith("java.io.FileDescriptor")
168 || clazz.getClassName().startsWith("gnu.gcj.runtime.")
169 || clazz.getClassName().startsWith("java.lang.")
171 if (!methods[i].getName().equals("<clinit>")) good = true;
173 if (methods[i].getCode() == null) {
174 System.out.println(" empty codeblock: " + clazz.getClassName() + "." + methods[i].getName());
176 System.out.println(" pruning " + clazz.getClassName() + "." + methods[i].getName());
177 if (deleteMethods) { cg.removeMethod(methods[i]); continue; }
178 MethodGen mg = new MethodGen(methods[i], clazz.getClassName(), newcpg);
179 mg.removeExceptions();
180 InstructionList il = new InstructionList();
181 mg.setInstructionList(il);
182 InstructionHandle ih_0 = il.append(factory.createNew("java.lang.UnsatisfiedLinkError"));
183 il.append(InstructionConstants.DUP);
184 il.append(factory.createInvoke("java.lang.UnsatisfiedLinkError",
185 "<init>", Type.VOID, Type.NO_ARGS, Constants.INVOKESPECIAL));
186 il.append(InstructionConstants.ATHROW);
189 mg.removeExceptions();
190 mg.removeLocalVariables();
191 mg.removeExceptionHandlers();
192 mg.removeLineNumbers();
193 cg.replaceMethod(methods[i], mg.getMethod());
199 new File(outdir + "/" + new File(clazz.getClassName().replace('.', '/')).getParent()).mkdirs();
200 System.out.println("dumping " + clazz.getClassName());
201 cg.getJavaClass().dump(outdir + "/" + clazz.getClassName().replace('.', '/') + ".class");
204 public JavaClass sig2class(String sig) throws Exception {
205 if (sig == null) return null;
206 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
207 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
208 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
210 if (sig.length() <= 1) return null;
211 if (sig.equals("<null object>")) return null;
212 if (sig.startsWith("<return address")) return null;
213 return repo.loadClass(sig);
215 public void load(String sig) throws Exception {
216 if (sig == null) return;
217 while (sig.length() > 0 && (sig.charAt(0) == 'L' || sig.charAt(0) == '[')) {
218 if (sig.charAt(0) == 'L') sig = sig.substring(1, sig.length() - 1);
219 else if (sig.charAt(0) == '[') sig = sig.substring(1, sig.length());
221 if (sig.length() <= 1) return;
222 if (sig.equals("<null object>")) return;
223 if (sig.startsWith("<return address")) return;
224 visitJavaClass(repo.loadClass(sig));
226 public void load(Type t) throws Exception {
227 if (t == null) return;
228 //String sig = t.getSignature();
229 if (t instanceof ArrayType) load(((ArrayType)t).getElementType());
230 if (!(t instanceof ObjectType)) return;
231 load(((ObjectType)t).getClassName());
234 // hashtable of hashsets
235 public static Hashtable subclasses = new Hashtable();
237 public String getMethodSignature(Method m, ConstantPoolGen cpg) throws Exception {
238 return m.getName() + m.getSignature();
241 public String getMethodSignature(InvokeInstruction ii, ConstantPoolGen cpg) throws Exception {
243 Type[] argtypes = ii.getArgumentTypes(cpg);
244 for(int j=0; j<argtypes.length; j++) sig += argtypes[j].getSignature();
245 return ii.getMethodName(cpg) + "(" + sig + ")" + ii.getReturnType(cpg).getSignature();
248 public static int level = 0;
249 public void visitJavaMethod(JavaClass jc, Method method) throws Exception {
251 if (jc.getClassName().equals("java.util.Date") && method.getName().equals("readObject")) return;
252 if (jc.getClassName().indexOf("SharedLib") != -1) return;
253 if (jc.getClassName().indexOf("Datagram") != -1) return;
254 if (dest.contains(method)) return;
256 // gcj bug; gcj can't compile this method from a .class file input
257 //if (jc.getClassName().equals("java.lang.System") && method.getName().equals("runFinalizersOnExit")) return;
261 for(int i=0; i<level; i++) System.out.print(" ");
262 ConstantPoolGen cpg = new ConstantPoolGen(method.getConstantPool());
263 System.out.println(jc.getClassName() + "." + getMethodSignature(method, cpg));
264 markMethodInSubclasses(jc, method, cpg);
265 if (method.getCode() == null) { level -= 2; return; }
266 byte[] code = method.getCode().getCode();
267 InstructionList il = new InstructionList(code);
268 Instruction[] instructions = il.getInstructions();
269 for(int i=0; i<instructions.length; i++){
270 Instruction instr = instructions[i];
271 if (instr instanceof LoadClass) load(((LoadClass)instr).getLoadClassType(cpg));
272 if (instr instanceof CPInstruction) load(((CPInstruction)instr).getType(cpg));
273 if (instr instanceof InvokeInstruction) {
274 InvokeInstruction ii = (InvokeInstruction)instr;
275 String ii_sig = getMethodSignature(ii, cpg);
276 JavaClass c = sig2class(ii.getLoadClassType(cpg).getSignature());
277 load(ii.getReturnType(cpg));
278 load(ii.getType(cpg));
279 Method[] meths = getMethods(c);
280 boolean good = false;
281 for(int i2=0; i2<meths.length; i2++) {
282 if (getMethodSignature(meths[i2], cpg).equals(ii_sig)) {
283 visitJavaMethod(c, meths[i2]);
288 if (!good) throw new Exception("couldn't find method " + getMethodSignature(ii, cpg) + " in " + c.getClassName());
292 load(method.getReturnType());
293 Type[] argtypes = method.getArgumentTypes();
294 for(int i=0; i<argtypes.length; i++) load(argtypes[i]);
295 if (method.getExceptionTable() != null) {
296 String[] exntypes = method.getExceptionTable().getExceptionNames();
297 for(int i=0; i<exntypes.length; i++) load(exntypes[i]);
301 public void visitJavaField(Field field) throws Exception {
302 if (dest.contains(field)) return;
304 load(field.getType());
307 public void visitJavaClass(JavaClass clazz) throws Exception {
308 if (dest.contains(clazz)) return;
311 ConstantPoolGen cpg = new ConstantPoolGen(clazz.getConstantPool());
312 String name = clazz.getClassName();
313 System.out.println(clazz.getClassName() + ".class");
315 JavaClass superclass = clazz.getSuperClass();
316 JavaClass[] interfaces = clazz.getAllInterfaces();
317 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
318 if (subclasses.get(sup) == null) subclasses.put(sup, new HashSet());
319 ((HashSet)subclasses.get(sup)).add(clazz);
321 for(int i=0; i<interfaces.length; i++) {
322 if (subclasses.get(interfaces[i]) == null) subclasses.put(interfaces[i], new HashSet());
323 ((HashSet)subclasses.get(interfaces[i])).add(clazz);
326 if (clazz.getClassName().startsWith("org.ibex."))
327 loadAllMethods(clazz.getClassName());
329 for(JavaClass sup = superclass; sup != null; sup = sup.getSuperClass()) {
331 remarkMethods(sup, clazz, cpg);
333 for(int i=0; i<interfaces.length; i++) {
334 visitJavaClass(interfaces[i]);
335 remarkMethods(interfaces[i], clazz, cpg);
338 Field[] fields = clazz.getFields();
339 Method[] methods = getMethods(clazz);
340 for(int i=0; i<fields.length; i++) visitJavaField(fields[i]);
341 for(int i=0; i<methods.length; i++) {
342 if (methods[i].getName().equals("<clinit>")) visitJavaMethod(clazz, methods[i]);
344 // only if ctor reachable (?)
345 if (methods[i].getName().equals("equals")) visitJavaMethod(clazz, methods[i]);
346 if (methods[i].getName().equals("hashCode")) visitJavaMethod(clazz, methods[i]);
347 if (methods[i].getName().equals("finalize")) visitJavaMethod(clazz, methods[i]);
348 if (methods[i].getName().equals("clone")) visitJavaMethod(clazz, methods[i]);
349 if (methods[i].getName().equals("toString")) visitJavaMethod(clazz, methods[i]);
353 public void markMethodInSubclasses(JavaClass c, Method m, JavaClass subclass, ConstantPoolGen cpg) throws Exception {
354 if (m.isStatic()) return;
355 String sig = getMethodSignature(m, cpg);
356 Method[] submethods = getMethods(subclass);
357 for(int j=0; j<submethods.length; j++)
358 if (getMethodSignature(submethods[j], cpg).equals(sig))
359 visitJavaMethod(subclass, submethods[j]);
361 public void markMethodInSubclasses(JavaClass c, Method m, ConstantPoolGen cpg) throws Exception {
362 if (m.isStatic()) return;
363 HashSet s = (HashSet)subclasses.get(c);
364 if (s == null) return;
365 Object[] subclasses = s.toArray();
366 for(int i=0; i<subclasses.length; i++) {
367 JavaClass subclass = (JavaClass)subclasses[i];
368 if (subclass == c) continue;
369 for(int j=0; j<level; j++) System.out.print(" ");
370 System.out.println(" [subclass " + subclass.getClassName() + "]");
371 markMethodInSubclasses(c, m, subclass, cpg);
375 public void remarkMethods(JavaClass c, ConstantPoolGen cpg) throws Exception {
376 Method[] meths =getMethods(c);
377 for(int j=0; j<meths.length; j++) if (dest.contains(meths[j])) markMethodInSubclasses(c, meths[j], cpg);
380 public void remarkMethods(JavaClass c, JavaClass target, ConstantPoolGen cpg) throws Exception {
381 Method[] meths = getMethods(c);
382 for(int j=0; j<meths.length; j++) if (dest.contains(meths[j])) markMethodInSubclasses(c, meths[j], target, cpg);
385 public static Hashtable methodsHashtable = new Hashtable();
386 public static Method[] getMethods(JavaClass c) {
387 Method[] ret = (Method[])methodsHashtable.get(c);
388 if (ret == null) methodsHashtable.put(c, ret = c.getMethods());