//
// enum.cs: Enum handling.
//
// Author: Miguel de Icaza (miguel@gnu.org)
// Ravi Pratap (ravi@ximian.com)
//
// Licensed under the terms of the GNU GPL
//
// (C) 2001 Ximian, Inc (http://www.ximian.com)
//
using System;
using System.Collections;
using System.Reflection;
using System.Reflection.Emit;
namespace Mono.CSharp {
///
/// Enumeration container
///
public class Enum : DeclSpace {
ArrayList ordered_enums;
public readonly string BaseType;
public Attributes OptAttributes;
public Type UnderlyingType;
Hashtable member_to_location;
//
// This is for members that have been defined
//
Hashtable member_to_value;
ArrayList field_builders;
public const int AllowedModifiers =
Modifiers.NEW |
Modifiers.PUBLIC |
Modifiers.PROTECTED |
Modifiers.INTERNAL |
Modifiers.PRIVATE;
public Enum (TypeContainer parent, string type, int mod_flags, string name, Attributes attrs, Location l)
: base (parent, name, l)
{
this.BaseType = type;
ModFlags = Modifiers.Check (AllowedModifiers, mod_flags, Modifiers.PUBLIC, l);
OptAttributes = attrs;
ordered_enums = new ArrayList ();
member_to_location = new Hashtable ();
member_to_value = new Hashtable ();
field_builders = new ArrayList ();
}
///
/// Adds @name to the enumeration space, with @expr
/// being its definition.
///
public AdditionResult AddEnumMember (string name, Expression expr, Location loc)
{
if (defined_names.Contains (name))
return AdditionResult.NameExists;
DefineName (name, expr);
ordered_enums.Add (name);
member_to_location.Add (name, loc);
return AdditionResult.Success;
}
//
// This is used by corlib compilation: we map from our
// type to a type that is consumable by the DefineField
//
Type MapToInternalType (Type t)
{
if (t == TypeManager.int32_type)
return typeof (int);
if (t == TypeManager.int64_type)
return typeof (long);
if (t == TypeManager.uint32_type)
return typeof (uint);
if (t == TypeManager.uint64_type)
return typeof (ulong);
if (t == TypeManager.float_type)
return typeof (float);
if (t == TypeManager.double_type)
return typeof (double);
if (t == TypeManager.byte_type)
return typeof (byte);
if (t == TypeManager.sbyte_type)
return typeof (sbyte);
if (t == TypeManager.char_type)
return typeof (char);
if (t == TypeManager.short_type)
return typeof (short);
if (t == TypeManager.ushort_type)
return typeof (ushort);
throw new Exception ();
}
public override TypeBuilder DefineType ()
{
if (TypeBuilder != null)
return TypeBuilder;
TypeAttributes attr = TypeAttributes.Class | TypeAttributes.Sealed;
UnderlyingType = TypeManager.LookupType (BaseType);
if (UnderlyingType != TypeManager.int32_type &&
UnderlyingType != TypeManager.uint32_type &&
UnderlyingType != TypeManager.int64_type &&
UnderlyingType != TypeManager.uint64_type &&
UnderlyingType != TypeManager.short_type &&
UnderlyingType != TypeManager.ushort_type &&
UnderlyingType != TypeManager.byte_type &&
UnderlyingType != TypeManager.sbyte_type) {
Report.Error (1008, Location,
"Type byte, sbyte, short, ushort, int, uint, " +
"long, or ulong expected (got: " +
TypeManager.CSharpName (UnderlyingType) + ")");
return null;
}
if (IsTopLevel) {
ModuleBuilder builder = CodeGen.ModuleBuilder;
if ((ModFlags & Modifiers.PUBLIC) != 0)
attr |= TypeAttributes.Public;
else
attr |= TypeAttributes.NotPublic;
TypeBuilder = builder.DefineType (Name, attr, TypeManager.enum_type);
} else {
TypeBuilder builder = Parent.TypeBuilder;
if ((ModFlags & Modifiers.PUBLIC) != 0)
attr |= TypeAttributes.NestedPublic;
else
attr |= TypeAttributes.NestedPrivate;
TypeBuilder = builder.DefineNestedType (
Basename, attr, TypeManager.enum_type);
}
//
// Call MapToInternalType for corlib
//
TypeBuilder.DefineField ("value__", UnderlyingType,
FieldAttributes.Public | FieldAttributes.SpecialName
| FieldAttributes.RTSpecialName);
TypeManager.AddEnumType (Name, TypeBuilder, this);
return TypeBuilder;
}
bool IsValidEnumConstant (Expression e)
{
if (!(e is Constant))
return false;
if (e is IntConstant || e is UIntConstant || e is LongConstant ||
e is ByteConstant || e is SByteConstant || e is ShortConstant ||
e is UShortConstant || e is ULongConstant || e is EnumConstant)
return true;
else
return false;
}
object GetNextDefaultValue (object default_value)
{
if (UnderlyingType == TypeManager.int32_type) {
int i = (int) default_value;
if (i < System.Int32.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.uint32_type) {
uint i = (uint) default_value;
if (i < System.UInt32.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.int64_type) {
long i = (long) default_value;
if (i < System.Int64.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.uint64_type) {
ulong i = (ulong) default_value;
if (i < System.UInt64.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.short_type) {
short i = (short) default_value;
if (i < System.Int16.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.ushort_type) {
ushort i = (ushort) default_value;
if (i < System.UInt16.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.byte_type) {
byte i = (byte) default_value;
if (i < System.Byte.MaxValue)
return ++i;
else
return null;
} else if (UnderlyingType == TypeManager.sbyte_type) {
sbyte i = (sbyte) default_value;
if (i < System.SByte.MaxValue)
return ++i;
else
return null;
}
return null;
}
void Error_ConstantValueCannotBeConverted (object val, Location loc)
{
if (val is Constant)
Report.Error (31, loc, "Constant value '" + ((Constant) val).AsString () +
"' cannot be converted" +
" to a " + TypeManager.CSharpName (UnderlyingType));
else
Report.Error (31, loc, "Constant value '" + val +
"' cannot be converted" +
" to a " + TypeManager.CSharpName (UnderlyingType));
return;
}
///
/// This is used to lookup the value of an enum member. If the member is undefined,
/// it attempts to define it and return its value
///
public object LookupEnumValue (EmitContext ec, string name, Location loc)
{
object default_value = null;
Constant c = null;
default_value = member_to_value [name];
if (default_value != null)
return default_value;
if (!defined_names.Contains (name)) {
Report.Error (117, loc, "'"+ Name + "' does not contain a definition for '"
+ name + "'");
return null;
}
//
// So if the above doesn't happen, we have a member that is undefined
// We now proceed to define it
//
Expression val = this [name];
if (val == null) {
int idx = ordered_enums.IndexOf (name);
if (idx == 0)
default_value = 0;
else {
for (int i = 0; i < idx; ++i) {
string n = (string) ordered_enums [i];
Location m_loc = (Mono.CSharp.Location)
member_to_location [n];
default_value = LookupEnumValue (ec, n, m_loc);
}
default_value = GetNextDefaultValue (default_value);
}
} else {
val = val.Resolve (ec);
if (val == null) {
Report.Error (-12, loc, "Definition is circular.");
return null;
}
if (IsValidEnumConstant (val)) {
c = (Constant) val;
default_value = c.GetValue ();
if (default_value == null) {
Error_ConstantValueCannotBeConverted (c, loc);
return null;
}
} else {
Report.Error (
1008, loc,
"Type byte, sbyte, short, ushort, int, uint, long, or " +
"ulong expected (have: " + val + ")");
return null;
}
}
FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
| FieldAttributes.Literal;
FieldBuilder fb = TypeBuilder.DefineField (name, UnderlyingType, attr);
try {
default_value = Convert.ChangeType (default_value, UnderlyingType);
} catch {
Error_ConstantValueCannotBeConverted (c, loc);
return null;
}
fb.SetConstant (default_value);
field_builders.Add (fb);
member_to_value [name] = default_value;
if (!TypeManager.RegisterFieldValue (fb, default_value))
return null;
return default_value;
}
public override bool Define (TypeContainer parent)
{
//
// If there was an error during DefineEnum, return
//
if (TypeBuilder == null)
return false;
EmitContext ec = new EmitContext (parent, this, Location, null,
UnderlyingType, ModFlags, false);
object default_value = 0;
FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
| FieldAttributes.Literal;
foreach (string name in ordered_enums) {
//
// Have we already been defined, thanks to some cross-referencing ?
//
if (member_to_value.Contains (name))
continue;
Location loc = (Mono.CSharp.Location) member_to_location [name];
if (this [name] != null) {
default_value = LookupEnumValue (ec, name, loc);
if (default_value == null)
return true;
} else {
FieldBuilder fb = TypeBuilder.DefineField (
name, UnderlyingType, attr);
if (default_value == null) {
Report.Error (543, loc, "Enumerator value for '" + name + "' is too large to " +
"fit in its type");
return false;
}
try {
default_value = Convert.ChangeType (default_value, UnderlyingType);
} catch {
Error_ConstantValueCannotBeConverted (default_value, loc);
return false;
}
fb.SetConstant (default_value);
field_builders.Add (fb);
member_to_value [name] = default_value;
if (!TypeManager.RegisterFieldValue (fb, default_value))
return false;
}
default_value = GetNextDefaultValue (default_value);
}
Attribute.ApplyAttributes (ec, TypeBuilder, this, OptAttributes, Location);
return true;
}
//
// Hack around System.Reflection as found everywhere else
//
public MemberInfo [] FindMembers (MemberTypes mt, BindingFlags bf,
MemberFilter filter, object criteria)
{
ArrayList members = new ArrayList ();
if ((mt & MemberTypes.Field) != 0) {
foreach (FieldBuilder fb in field_builders)
if (filter (fb, criteria) == true)
members.Add (fb);
}
int count = members.Count;
if (count > 0) {
MemberInfo [] mi = new MemberInfo [count];
members.CopyTo (mi, 0);
return mi;
}
return null;
}
public ArrayList ValueNames {
get {
return ordered_enums;
}
}
// indexer
public Expression this [string name] {
get {
return (Expression) defined_names [name];
}
}
}
}