package jnr.ffi.provider.jffi;
import jnr.ffi.Pointer;
import jnr.ffi.Runtime;
import jnr.ffi.Struct;
import jnr.ffi.mapper.FromNativeContext;
import jnr.ffi.mapper.FromNativeConverter;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Label;
import java.io.PrintWriter;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
import static jnr.ffi.provider.jffi.CodegenUtils.ci;
import static jnr.ffi.provider.jffi.CodegenUtils.p;
import static jnr.ffi.provider.jffi.CodegenUtils.sig;
import static org.objectweb.asm.Opcodes.*;
@FromNativeConverter.NoContext
@FromNativeConverter.Cacheable
abstract public class AsmStructByReferenceFromNativeConverter implements FromNativeConverter<Struct, Pointer> {
private final jnr.ffi.Runtime runtime;
private final int flags;
protected AsmStructByReferenceFromNativeConverter(jnr.ffi.Runtime runtime, int flags) {
this.runtime = runtime;
this.flags = flags;
}
public final Class<Pointer> nativeType() {
return Pointer.class;
}
// getRuntime() is called from generated code
protected final jnr.ffi.Runtime getRuntime() {
return runtime;
}
static final Map<Class<? extends Struct>, Class<? extends AsmStructByReferenceFromNativeConverter>> converterClasses
= new ConcurrentHashMap<Class<? extends Struct>, Class<? extends AsmStructByReferenceFromNativeConverter>>();
static AsmStructByReferenceFromNativeConverter newStructByReferenceConverter(jnr.ffi.Runtime runtime, Class<? extends Struct> structClass, int flags, AsmClassLoader classLoader) {
Class<? extends AsmStructByReferenceFromNativeConverter> converterClass = converterClasses.get(structClass);
if (converterClass == null) {
synchronized (converterClasses) {
if ((converterClass = converterClasses.get(structClass)) == null) {
converterClasses.put(structClass, converterClass = newStructByReferenceClass(structClass, classLoader));
}
}
}
try {
return converterClass.getConstructor(jnr.ffi.Runtime.class, int.class).newInstance(runtime, flags);
} catch (NoSuchMethodException nsme) {
throw new RuntimeException(nsme);
} catch (IllegalAccessException iae) {
throw new RuntimeException(iae);
} catch (InstantiationException ie) {
throw new RuntimeException(ie);
} catch (InvocationTargetException ite) {
throw new RuntimeException(ite);
}
}
private static final AtomicLong nextClassID = new AtomicLong(0);
static Class<? extends AsmStructByReferenceFromNativeConverter> newStructByReferenceClass(Class<? extends Struct> structClass, AsmClassLoader classLoader) {
try {
Constructor<? extends Struct> cons = structClass.asSubclass(Struct.class).getConstructor(jnr.ffi.Runtime.class);
if (!Modifier.isPublic(cons.getModifiers())) {
throw new RuntimeException(structClass.getName() + " constructor is not public");
}
} catch (NoSuchMethodException ex) {
throw new RuntimeException("struct subclass " + structClass.getName() + " has no constructor that takes a "
+ jnr.ffi.Runtime.class.getName(), ex);
}
ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
ClassVisitor cv = AsmLibraryLoader.DEBUG ? AsmUtil.newCheckClassAdapter(cw) : cw;
final String className = p(structClass) + "$jnr$fromNativeConverter$" + nextClassID.getAndIncrement();
cv.visit(V1_5, ACC_PUBLIC | ACC_FINAL, className, null, p(AsmStructByReferenceFromNativeConverter.class),
new String[0]);
cv.visitAnnotation(ci(FromNativeConverter.NoContext.class), true);
// Create the constructor to set the instance fields
SkinnyMethodAdapter init = new SkinnyMethodAdapter(cv, ACC_PUBLIC, "<init>", sig(void.class, jnr.ffi.Runtime.class, int.class), null, null);
init.start();
// Invoke the super class constructor as super(Library)
init.aload(0);
init.aload(1);
init.iload(2);
init.invokespecial(p(AsmStructByReferenceFromNativeConverter.class), "<init>", sig(void.class, jnr.ffi.Runtime.class, int.class));
init.voidreturn();
init.visitMaxs(10, 10);
init.visitEnd();
SkinnyMethodAdapter fromNative = new SkinnyMethodAdapter(cv, ACC_PUBLIC | ACC_FINAL, "fromNative",
sig(structClass, Pointer.class, FromNativeContext.class), null, null);
fromNative.start();
Label nullPointer = new Label();
fromNative.aload(1);
fromNative.ifnull(nullPointer);
// Create an instance of the struct subclass
fromNative.newobj(p(structClass));
fromNative.dup();
fromNative.aload(0);
fromNative.invokevirtual(p(AsmStructByReferenceFromNativeConverter.class), "getRuntime", sig(Runtime.class));
fromNative.invokespecial(structClass, "<init>", void.class, jnr.ffi.Runtime.class);
// associate the memory with the struct and return the struct
fromNative.dup();
fromNative.aload(1);
fromNative.invokevirtual(structClass, "useMemory", void.class, Pointer.class);
fromNative.areturn();
fromNative.label(nullPointer);
fromNative.aconst_null();
fromNative.areturn();
fromNative.visitAnnotation(ci(FromNativeConverter.NoContext.class), true);
fromNative.visitMaxs(10, 10);
fromNative.visitEnd();
fromNative = new SkinnyMethodAdapter(cv, ACC_PUBLIC | ACC_FINAL, "fromNative",
sig(Object.class, Object.class, FromNativeContext.class), null, null);
fromNative.start();
fromNative.aload(0);
fromNative.aload(1);
fromNative.checkcast(Pointer.class);
fromNative.aload(2);
fromNative.invokevirtual(className, "fromNative", sig(structClass, Pointer.class, FromNativeContext.class));
fromNative.areturn();
fromNative.visitAnnotation(ci(FromNativeConverter.NoContext.class), true);
fromNative.visitMaxs(10, 10);
fromNative.visitEnd();
cv.visitEnd();
try {
byte[] bytes = cw.toByteArray();
if (AsmLibraryLoader.DEBUG) {
ClassVisitor trace = AsmUtil.newTraceClassVisitor(new PrintWriter(System.err));
new ClassReader(bytes).accept(trace, 0);
}
return classLoader.defineClass(className.replace("/", "."), bytes);
} catch (Throwable ex) {
throw new RuntimeException(ex);
}
}
}