// ==========================================================================
// This software is subject to the provisions of the Zope Public License,
// Version 2.0 (ZPL). A copy of the ZPL should accompany this distribution.
// THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
// WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
// FOR A PARTICULAR PURPOSE.
// ==========================================================================
using System;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Globalization;
using System.Security;
namespace Python.Runtime {
//========================================================================
// Performs data conversions between managed types and Python types.
//========================================================================
[SuppressUnmanagedCodeSecurityAttribute()]
internal class Converter {
private Converter() {}
static NumberFormatInfo nfi;
static Type objectType;
static Type stringType;
static Type doubleType;
static Type int32Type;
static Type int64Type;
static Type flagsType;
static Type boolType;
static Type typeType;
static Converter () {
nfi = NumberFormatInfo.InvariantInfo;
objectType = typeof(Object);
stringType = typeof(String);
int32Type = typeof(Int32);
int64Type = typeof(Int64);
doubleType = typeof(Double);
flagsType = typeof(FlagsAttribute);
boolType = typeof(Boolean);
typeType = typeof(Type);
}
//====================================================================
// Given a builtin Python type, return the corresponding CLR type.
//====================================================================
internal static Type GetTypeByAlias(IntPtr op) {
if ((op == Runtime.PyStringType) ||
(op == Runtime.PyUnicodeType)) {
return stringType;
}
else if (op == Runtime.PyIntType) {
return int32Type;
}
else if (op == Runtime.PyLongType) {
return int64Type;
}
else if (op == Runtime.PyFloatType) {
return doubleType;
}
else if (op == Runtime.PyBoolType) {
return boolType;
}
return null;
}
//====================================================================
// Return a Python object for the given native object, converting
// basic types (string, int, etc.) into equivalent Python objects.
// This always returns a new reference. Note that the System.Decimal
// type has no Python equivalent and converts to a managed instance.
//====================================================================
internal static IntPtr ToPython(Object value, Type type) {
IntPtr result = IntPtr.Zero;
// Null always converts to None in Python.
if (value == null) {
result = Runtime.PyNone;
Runtime.Incref(result);
return result;
}
// hmm - from Python, we almost never care what the declared
// type is. we'd rather have the object bound to the actual
// implementing class.
type = value.GetType();
TypeCode tc = Type.GetTypeCode(type);
switch(tc) {
case TypeCode.Object:
result = CLRObject.GetInstHandle(value, type);
// XXX - hack to make sure we convert new-style class based
// managed exception instances to wrappers ;(
if (Runtime.wrap_exceptions) {
Exception e = value as Exception;
if (e != null) {
return Exceptions.GetExceptionInstanceWrapper(result);
}
}
return result;
case TypeCode.String:
return Runtime.PyUnicode_FromString((string)value);
case TypeCode.Int32:
return Runtime.PyInt_FromInt32((int)value);
case TypeCode.Boolean:
if ((bool)value) {
Runtime.Incref(Runtime.PyTrue);
return Runtime.PyTrue;
}
Runtime.Incref(Runtime.PyFalse);
return Runtime.PyFalse;
case TypeCode.Byte:
return Runtime.PyInt_FromInt32((int)((byte)value));
case TypeCode.Char:
return Runtime.PyUnicode_FromOrdinal((int)((char)value));
case TypeCode.Int16:
return Runtime.PyInt_FromInt32((int)((short)value));
case TypeCode.Int64:
return Runtime.PyLong_FromLongLong((long)value);
case TypeCode.Single:
// return Runtime.PyFloat_FromDouble((double)((float)value));
string ss = ((float)value).ToString(nfi);
IntPtr ps = Runtime.PyString_FromString(ss);
IntPtr op = Runtime.PyFloat_FromString(ps, IntPtr.Zero);
Runtime.Decref(ps);
return op;
case TypeCode.Double:
return Runtime.PyFloat_FromDouble((double)value);
case TypeCode.SByte:
return Runtime.PyInt_FromInt32((int)((sbyte)value));
case TypeCode.UInt16:
return Runtime.PyInt_FromInt32((int)((ushort)value));
case TypeCode.UInt32:
return Runtime.PyLong_FromUnsignedLong((uint)value);
case TypeCode.UInt64:
return Runtime.PyLong_FromUnsignedLongLong((ulong)value);
default:
result = CLRObject.GetInstHandle(value, type);
return result;
}
}
//====================================================================
// In a few situations, we don't have any advisory type information
// when we want to convert an object to Python.
//====================================================================
internal static IntPtr ToPythonImplicit(Object value) {
if (value == null) {
IntPtr result = Runtime.PyNone;
Runtime.Incref(result);
return result;
}
return ToPython(value, objectType);
}
//====================================================================
// Return a managed object for the given Python object, taking funny
// byref types into account.
//====================================================================
internal static bool ToManaged(IntPtr value, Type type,
out object result, bool setError) {
if (type.IsByRef) {
type = type.GetElementType();
}
return Converter.ToManagedValue(value, type, out result, setError);
}
internal static bool ToManagedValue(IntPtr value, Type obType,
out Object result, bool setError) {
// Common case: if the Python value is a wrapped managed object
// instance, just return the wrapped object.
ManagedType mt = ManagedType.GetManagedObject(value);
result = null;
// XXX - hack to support objects wrapped in old-style classes
// (such as exception objects).
if (Runtime.wrap_exceptions) {
if (mt == null) {
if (Runtime.PyObject_IsInstance(
value, Exceptions.Exception
) > 0) {
IntPtr p = Runtime.PyObject_GetAttrString(value, "_inner");
if (p != IntPtr.Zero) {
// This is safe because we know that the __dict__ of
// value holds a reference to _inner.
value = p;
Runtime.Decref(p);
mt = ManagedType.GetManagedObject(value);
}
}
IntPtr c = Exceptions.UnwrapExceptionClass(value);
if ((c != IntPtr.Zero) && (c != value)) {
value = c;
Runtime.Decref(c);
mt = ManagedType.GetManagedObject(value);
}
}
}
if (mt != null) {
if (mt is CLRObject) {
object tmp = ((CLRObject)mt).inst;
if (obType.IsInstanceOfType(tmp)) {
result = tmp;
return true;
}
string err = "value cannot be converted to {0}";
err = String.Format(err, obType);
Exceptions.SetError(Exceptions.TypeError, err);
return false;
}
if (mt is ClassBase) {
result = ((ClassBase)mt).type;
return true;
}
// shouldnt happen
return false;
}
if (value == Runtime.PyNone && !obType.IsValueType) {
result = null;
return true;
}
if (obType.IsArray) {
return ToArray(value, obType, out result, setError);
}
if (obType.IsEnum) {
return ToEnum(value, obType, out result, setError);
}
// Conversion to 'Object' is done based on some reasonable
// default conversions (Python string -> managed string,
// Python int -> Int32 etc.).
if (obType == objectType) {
if (Runtime.IsStringType(value)) {
return ToPrimitive(value, stringType, out result,
setError);
}
else if (Runtime.PyBool_Check(value)) {
return ToPrimitive(value, boolType, out result, setError);
}
else if (Runtime.PyInt_Check(value)) {
return ToPrimitive(value, int32Type, out result, setError);
}
else if (Runtime.PyLong_Check(value)) {
return ToPrimitive(value, int64Type, out result, setError);
}
else if (Runtime.PySequence_Check(value)) {
return ToArray(value, typeof(object[]), out result,
setError);
}
if (setError) {
Exceptions.SetError(Exceptions.TypeError,
"value cannot be converted to Object"
);
}
return false;
}
return ToPrimitive(value, obType, out result, setError);
}
//====================================================================
// Convert a Python value to an instance of a primitive managed type.
//====================================================================
static bool ToPrimitive(IntPtr value, Type obType, out Object result,
bool setError) {
IntPtr overflow = Exceptions.OverflowError;
TypeCode tc = Type.GetTypeCode(obType);
result = null;
IntPtr op;
int ival;
switch(tc) {
case TypeCode.String:
string st = Runtime.GetManagedString(value);
if (st == null) {
goto type_error;
}
result = st;
return true;
case TypeCode.Int32:
// Trickery to support 64-bit platforms.
if (IntPtr.Size == 4) {
op = Runtime.PyNumber_Int(value);
// As of Python 2.3, large ints magically convert :(
if (Runtime.PyLong_Check(op) ) {
Runtime.Decref(op);
goto overflow;
}
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ival = (int)Runtime.PyInt_AsLong(op);
Runtime.Decref(op);
result = ival;
return true;
}
else {
op = Runtime.PyNumber_Long(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
long ll = (long)Runtime.PyLong_AsLongLong(op);
Runtime.Decref(op);
if ((ll == -1) && Exceptions.ErrorOccurred()) {
goto overflow;
}
if (ll > Int32.MaxValue || ll < Int32.MinValue) {
goto overflow;
}
result = (int)ll;
return true;
}
case TypeCode.Boolean:
result = (Runtime.PyObject_IsTrue(value) != 0);
return true;
case TypeCode.Byte:
if (Runtime.PyObject_TypeCheck(value, Runtime.PyStringType)) {
if (Runtime.PyString_Size(value) == 1) {
op = Runtime.PyString_AS_STRING(value);
result = (byte)Marshal.ReadByte(op);
return true;
}
goto type_error;
}
op = Runtime.PyNumber_Int(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ival = (int) Runtime.PyInt_AsLong(op);
Runtime.Decref(op);
if (ival > Byte.MaxValue || ival < Byte.MinValue) {
goto overflow;
}
byte b = (byte) ival;
result = b;
return true;
case TypeCode.SByte:
if (Runtime.PyObject_TypeCheck(value, Runtime.PyStringType)) {
if (Runtime.PyString_Size(value) == 1) {
op = Runtime.PyString_AS_STRING(value);
result = (sbyte)Marshal.ReadByte(op);
return true;
}
goto type_error;
}
op = Runtime.PyNumber_Int(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ival = (int) Runtime.PyInt_AsLong(op);
Runtime.Decref(op);
if (ival > SByte.MaxValue || ival < SByte.MinValue) {
goto overflow;
}
sbyte sb = (sbyte) ival;
result = sb;
return true;
case TypeCode.Char:
if (Runtime.PyObject_TypeCheck(value, Runtime.PyStringType)) {
if (Runtime.PyString_Size(value) == 1) {
op = Runtime.PyString_AS_STRING(value);
result = (char)Marshal.ReadByte(op);
return true;
}
goto type_error;
}
else if (Runtime.PyObject_TypeCheck(value,
Runtime.PyUnicodeType)) {
if (Runtime.PyUnicode_GetSize(value) == 1) {
op = Runtime.PyUnicode_AS_UNICODE(value);
result = (char)Marshal.ReadInt16(op);
return true;
}
goto type_error;
}
op = Runtime.PyNumber_Int(value);
if (op == IntPtr.Zero) {
goto type_error;
}
ival = Runtime.PyInt_AsLong(op);
if (ival > Char.MaxValue || ival < Char.MinValue) {
goto overflow;
}
Runtime.Decref(op);
result = (char)ival;
return true;
case TypeCode.Int16:
op = Runtime.PyNumber_Int(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ival = (int) Runtime.PyInt_AsLong(op);
Runtime.Decref(op);
if (ival > Int16.MaxValue || ival < Int16.MinValue) {
goto overflow;
}
short s = (short) ival;
result = s;
return true;
case TypeCode.Int64:
op = Runtime.PyNumber_Long(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
long l = (long)Runtime.PyLong_AsLongLong(op);
Runtime.Decref(op);
if ((l == -1) && Exceptions.ErrorOccurred()) {
goto overflow;
}
result = l;
return true;
case TypeCode.UInt16:
op = Runtime.PyNumber_Int(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ival = (int) Runtime.PyInt_AsLong(op);
Runtime.Decref(op);
if (ival > UInt16.MaxValue || ival < UInt16.MinValue) {
goto overflow;
}
ushort us = (ushort) ival;
result = us;
return true;
case TypeCode.UInt32:
op = Runtime.PyNumber_Long(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
uint ui = (uint)Runtime.PyLong_AsUnsignedLong(op);
Runtime.Decref(op);
if (Exceptions.ErrorOccurred()) {
goto overflow;
}
result = ui;
return true;
case TypeCode.UInt64:
op = Runtime.PyNumber_Long(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
ulong ul = (ulong)Runtime.PyLong_AsUnsignedLongLong(op);
Runtime.Decref(op);
if (Exceptions.ErrorOccurred()) {
goto overflow;
}
result = ul;
return true;
case TypeCode.Single:
op = Runtime.PyNumber_Float(value);
if (op == IntPtr.Zero) {
if (Exceptions.ExceptionMatches(overflow)) {
goto overflow;
}
goto type_error;
}
double dd = Runtime.PyFloat_AsDouble(value);
if (dd > Single.MaxValue || dd < Single.MinValue) {
goto overflow;
}
result = (float)dd;
return true;
case TypeCode.Double:
op = Runtime.PyNumber_Float(value);
if (op == IntPtr.Zero) {
goto type_error;
}
double d = Runtime.PyFloat_AsDouble(op);
Runtime.Decref(op);
if (d > Double.MaxValue || d < Double.MinValue) {
goto overflow;
}
result = d;
return true;
}
type_error:
if (setError) {
string format = "'{0}' value cannot be converted to {1}";
string tpName = Runtime.PyObject_GetTypeName(value);
string error = String.Format(format, tpName, obType);
Exceptions.SetError(Exceptions.TypeError, error);
}
return false;
overflow:
if (setError) {
string error = "value too large to convert";
Exceptions.SetError(Exceptions.OverflowError, error);
}
return false;
}
static void SetConversionError(IntPtr value, Type target) {
IntPtr ob = Runtime.PyObject_Repr(value);
string src = Runtime.GetManagedString(ob);
Runtime.Decref(ob);
string error = String.Format(
"Cannot convert {0} to {1}", src, target
);
Exceptions.SetError(Exceptions.TypeError, error);
}
//====================================================================
// Convert a Python value to a correctly typed managed array instance.
// The Python value must support the Python sequence protocol and the
// items in the sequence must be convertible to the target array type.
//====================================================================
static bool ToArray(IntPtr value, Type obType, out Object result,
bool setError) {
Type elementType = obType.GetElementType();
int size = Runtime.PySequence_Size(value);
result = null;
if (size < 0) {
if (setError) {
SetConversionError(value, obType);
}
return false;
}
Array items = Array.CreateInstance(elementType, size);
// XXX - is there a better way to unwrap this if it is a real
// array?
for (int i = 0; i < size; i++) {
Object obj = null;
IntPtr item = Runtime.PySequence_GetItem(value, i);
if (item == IntPtr.Zero) {
if (setError) {
SetConversionError(value, obType);
return false;
}
}
if (!Converter.ToManaged(item, elementType, out obj, true)) {
Runtime.Decref(item);
return false;
}
items.SetValue(obj, i);
Runtime.Decref(item);
}
result = items;
return true;
}
//====================================================================
// Convert a Python value to a correctly typed managed enum instance.
//====================================================================
static bool ToEnum(IntPtr value, Type obType, out Object result,
bool setError) {
Type etype = Enum.GetUnderlyingType(obType);
result = null;
if (!ToPrimitive(value, etype, out result, setError)) {
return false;
}
if (Enum.IsDefined(obType, result)) {
result = Enum.ToObject(obType, result);
return true;
}
if (obType.GetCustomAttributes(flagsType, true).Length > 0) {
result = Enum.ToObject(obType, result);
return true;
}
if (setError) {
string error = "invalid enumeration value";
Exceptions.SetError(Exceptions.ValueError, error);
}
return false;
}
}
}