/**
* Determine the name of parameter with index i in the given method. Use the locals attributes
* about local variables from the classfile. Note: This is still work in progress.
*
* @param method
* @param locals
* @param i
* @return the name of the parameter if available or a number if not.
*/
static String parameterNameFor(CtBehavior method, LocalVariableAttribute locals, int i) {
if (locals == null) {
return Integer.toString(i + 1);
}
int modifiers = method.getModifiers();
int j = i;
if (Modifier.isSynchronized(modifiers)) {
// skip object to synchronize upon.
j++;
// System.err.println("Synchronized");
}
if (Modifier.isStatic(modifiers) == false) {
// skip "this"
j++;
// System.err.println("Instance");
}
String variableName = locals.variableName(j);
// if (variableName.equals("this")) {
// System.err.println("'this' returned as a parameter name for "
// + method.getName() + " index " + j
// +
// ", names are probably shifted. Please submit source for class in slf4j bugreport");
// }
return variableName;
}
private Object[] extractParams(Mapping mapping, HttpServletRequest request) {
Object[] params;
ClassPool pool = ClassPool.getDefault();
pool.insertClassPath(new ClassClassPath(mapping.clazz));
CtMethod cm = null;
CtClass[] parameterTypes = new CtClass[0];
try {
cm = pool.get(mapping.clazz.getName()).getDeclaredMethod(mapping.method.getName());
parameterTypes = cm.getParameterTypes();
} catch (NotFoundException e) {
e.printStackTrace();
}
if (0 == parameterTypes.length) return new Object[0];
params = new Object[parameterTypes.length];
LocalVariableAttribute attr =
(LocalVariableAttribute)
cm.getMethodInfo().getCodeAttribute().getAttribute(LocalVariableAttribute.tag);
int pos = Modifier.isStatic(cm.getModifiers()) ? 0 : 1;
for (int i = 0; i < params.length; i++) {
String name = attr.variableName(i + pos);
String typeName = parameterTypes[i].getName();
Binder binder = Binder.valueOf(typeName);
Object param = binder.get(name, request, mapping);
params[i] = param;
}
return params;
}
private void initExtraHarvest() {
try {
CtClass terraForming =
HookManager.getInstance()
.getClassPool()
.get("com.wurmonline.server.behaviours.Terraforming");
CtClass[] paramTypes = {
HookManager.getInstance().getClassPool().get("com.wurmonline.server.creatures.Creature"),
CtPrimitiveType.intType,
CtPrimitiveType.intType,
CtPrimitiveType.booleanType,
CtPrimitiveType.intType,
CtPrimitiveType.floatType,
HookManager.getInstance().getClassPool().get("com.wurmonline.server.items.Item")
};
CtMethod method =
terraForming.getMethod(
"harvest", Descriptor.ofMethod(CtPrimitiveType.booleanType, paramTypes));
MethodInfo methodInfo = method.getMethodInfo();
CodeAttribute codeAttribute = methodInfo.getCodeAttribute();
CodeIterator codeIterator = codeAttribute.iterator();
LocalVariableAttribute attr =
(LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);
int quantityIndex = -1;
for (int i = 0; i < attr.tableLength(); i++) {
if ("quantity".equals(attr.variableName(i))) {
quantityIndex = attr.index(i);
}
}
if (quantityIndex == -1) {
throw new HookException("Quantity variable can not be resolved");
}
while (codeIterator.hasNext()) {
int pos = codeIterator.next();
int op = codeIterator.byteAt(pos);
if (op == CodeIterator.ISTORE) {
int fieldRefIdx = codeIterator.byteAt(pos + 1);
if (quantityIndex == fieldRefIdx) {
Bytecode bytecode = new Bytecode(codeIterator.get().getConstPool());
bytecode.addIconst(extraHarvest);
bytecode.add(Bytecode.IADD);
codeIterator.insertAt(pos, bytecode.get());
break;
}
}
}
} catch (NotFoundException | BadBytecode e) {
throw new HookException(e);
}
}