package jnr.ffi.provider.jffi;
import com.kenai.jffi.CallContext;
import com.kenai.jffi.CallingConvention;
import com.kenai.jffi.Platform;
import jnr.ffi.NativeType;
import jnr.ffi.Pointer;
import static jnr.ffi.provider.jffi.AsmUtil.isDelegate;
import static jnr.ffi.provider.jffi.CodegenUtils.ci;
import static jnr.ffi.provider.jffi.NumberUtil.sizeof;
import static jnr.ffi.provider.jffi.Util.getBooleanProperty;
/**
*
*/
final class FastIntMethodGenerator extends AbstractFastNumericMethodGenerator {
private static final boolean ENABLED = getBooleanProperty("jnr.ffi.fast-int.enabled", true);
private static final int MAX_FASTINT_PARAMETERS = getMaximumFastIntParameters();
private static final String[] signatures;
private static final String[] methodNames = {
"invokeI0", "invokeI1", "invokeI2", "invokeI3", "invokeI4", "invokeI5", "invokeI6"
};
static {
signatures = new String[MAX_FASTINT_PARAMETERS + 1];
for (int i = 0; i <= MAX_FASTINT_PARAMETERS; i++) {
StringBuilder sb = new StringBuilder();
sb.append('(').append(ci(CallContext.class)).append(ci(long.class));
for (int n = 0; n < i; n++) {
sb.append('I');
}
signatures[i] = sb.append(")I").toString();
}
}
@Override
String getInvokerMethodName(ResultType resultType, ParameterType[] parameterTypes, boolean ignoreErrno) {
final int parameterCount = parameterTypes.length;
if (parameterCount <= MAX_FASTINT_PARAMETERS && parameterCount <= methodNames.length) {
return methodNames[parameterCount];
} else {
throw new IllegalArgumentException("invalid fast-int parameter count: " + parameterCount);
}
}
@Override
String getInvokerSignature(int parameterCount, Class nativeIntType) {
if (parameterCount <= MAX_FASTINT_PARAMETERS && parameterCount <= signatures.length) {
return signatures[parameterCount];
}
throw new IllegalArgumentException("invalid fast-int parameter count: " + parameterCount);
}
final Class getInvokerType() {
return int.class;
}
public boolean isSupported(ResultType resultType, ParameterType[] parameterTypes, CallingConvention callingConvention) {
final int parameterCount = parameterTypes.length;
if (!ENABLED) {
return false;
}
if (!callingConvention.equals(CallingConvention.DEFAULT) || parameterCount > MAX_FASTINT_PARAMETERS) {
return false;
}
final Platform platform = Platform.getPlatform();
if (platform.getOS().equals(Platform.OS.WINDOWS)) {
return false;
}
if (!platform.getCPU().equals(Platform.CPU.I386) && !platform.getCPU().equals(Platform.CPU.X86_64)) {
return false;
}
for (ParameterType parameterType : parameterTypes) {
if (!isFastIntParameter(platform, parameterType)) {
return false;
}
}
return isFastIntResult(platform, resultType);
}
static int getMaximumFastIntParameters() {
try {
com.kenai.jffi.Invoker.class.getDeclaredMethod("invokeI6", CallContext.class, long.class,
int.class, int.class, int.class, int.class, int.class, int.class);
return 6;
} catch (Throwable t) {
return 0;
}
}
static boolean isFastIntType(Platform platform, SigType type) {
switch (type.nativeType) {
case SCHAR:
case UCHAR:
case SSHORT:
case USHORT:
case SINT:
case UINT:
case SLONG:
case ULONG:
return sizeof(type.nativeType) <= 4;
default:
return false;
}
}
private static boolean isSupportedPointerParameterType(Class javaParameterType) {
return Pointer.class.isAssignableFrom(javaParameterType);
}
static boolean isFastIntResult(Platform platform, ResultType resultType) {
return isFastIntType(platform, resultType)
|| resultType.nativeType == NativeType.VOID
|| (resultType.nativeType == NativeType.ADDRESS && sizeof(resultType)== 4)
;
}
static boolean isFastIntParameter(Platform platform, ParameterType parameterType) {
return isFastIntType(platform, parameterType)
|| (parameterType.nativeType == NativeType.ADDRESS && sizeof(parameterType)== 4)
&& isSupportedPointerParameterType(parameterType.effectiveJavaType());
}
}