(DISTFILES): Comment out a few missing files.

[mono-project.git] / mcs / mbas / rootcontext.cs

//
// rootcontext.cs: keeps track of our tree representation, and assemblies loaded.
//
// Author: Miguel de Icaza (miguel@ximian.com)
//         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;
using System.Diagnostics;

namespace Mono.MonoBASIC {

        public class RootContext {

                //
                // Contains the parsed tree
                //
                static Tree tree;

                //
                // Tracks Imported namespaces
                //
                static SourceBeingCompiled sourceBeingCompiled = new SourceBeingCompiled();

                //
                // This hashtable contains all of the #definitions across the source code
                // it is used by the ConditionalAttribute handler.
                //
                public static Hashtable AllDefines = new Hashtable ();
                
                //
                // Whether we are being linked against the standard libraries.
                // This is only used to tell whether `System.Object' should
                // have a parent or not.
                //
                public static bool StdLib = true;

                //
                // This keeps track of the order in which classes were defined
                // so that we can poulate them in that order.
                //
                // Order is important, because we need to be able to tell by
                // examining the parent's list of methods which ones are virtual
                // or abstract as well as the parent names (to implement new, 
                // override).
                //
                static ArrayList type_container_resolve_order;
                static ArrayList interface_resolve_order;
                static ArrayList attribute_types;

                //
                // Holds a reference to the Private Implementation Details
                // class.
                //
                static TypeBuilder impl_details_class;

                public static int WarningLevel = 2;
                
                //
                // Constructor
                //
                static RootContext ()
                {
                        tree = new Tree ();
                        interface_resolve_order = new ArrayList ();
                        type_container_resolve_order = new ArrayList ();
                }

                static public Tree Tree {
                        get {
                                return tree;
                        }
                }

                static public string MainClass;
                
                public static void RegisterOrder (Interface iface)
                {
                        interface_resolve_order.Add (iface);
                }
                
                public static void RegisterOrder (TypeContainer tc)
                {
                        type_container_resolve_order.Add (tc);
                }

                public static void RegisterAttribute (TypeContainer tc)
                {
                        if (attribute_types == null)
                                attribute_types = new ArrayList ();
                        
                        attribute_types.Add (tc);
                }
                
                public static void InitializeImports(ArrayList ImportsList)
                {
                        sourceBeingCompiled.InitializeImports (ImportsList);
                }

                public static SourceBeingCompiled SourceBeingCompiled
                {
                        get { return sourceBeingCompiled; }
                }

                public static void VerifyImports()
                {
                        sourceBeingCompiled.VerifyImports();
                }

                // 
                // The default compiler checked state
                //
                static public bool Checked = false;

                //
                // Whether to allow Unsafe code
                //
                static public bool Unsafe = false;
                
                // Root namespace name (implicit namespace)
                static public string RootNamespace = "";
                
                static string MakeFQN (string nsn, string name)
                {
                        string prefix = (nsn == "" ? "" : nsn + ".");

                        return prefix + name;
                }
                       
                // <remarks>
                //   This function is used to resolve the hierarchy tree.
                //   It processes interfaces, structs and classes in that order.
                //
                //   It creates the TypeBuilder's as it processes the user defined
                //   types.  
                // </remarks>
                static public void ResolveTree ()
                {
                        //
                        // Process the attribute types separately and before anything else
                        //
                        if (attribute_types != null)
                                foreach (TypeContainer tc in attribute_types)
                                        tc.DefineType ();
                        
                        //
                        // Interfaces are processed next, as classes and
                        // structs might inherit from an object or implement
                        // a set of interfaces, we need to be able to tell
                        // them appart by just using the TypeManager.
                        //
                        TypeContainer root = Tree.Types;

                        ArrayList ifaces = root.Interfaces;
                        if (ifaces != null){
                                foreach (Interface i in ifaces) 
                                        i.DefineType ();
                        }

                        
                        foreach (TypeContainer tc in root.Types) 
                                tc.DefineType ();

                        if (root.Delegates != null)
                                foreach (Delegate d in root.Delegates) 
                                        d.DefineType ();

                        if (root.Enums != null)
                                foreach (Enum e in root.Enums)
                                        e.DefineType ();
                        
                }

                static void Error_TypeConflict (string name, Location loc)
                {
                        Report.Error (
                                520, loc, "`" + name + "' conflicts with a predefined type");
                }

                static void Error_TypeConflict (string name)
                {
                        Report.Error (
                                520, "`" + name + "' conflicts with a predefined type");
                }

                //
                // Resolves a single class during the corlib bootstrap process
                //
                static TypeBuilder BootstrapCorlib_ResolveClass (TypeContainer root, string name)
                {
                        object o = root.GetDefinition (name);
                        if (o == null){
                                Report.Error (518, "The predefined type `" + name + "' is not defined");
                                return null;
                        }

                        if (!(o is Class)){
                                if (o is DeclSpace){
                                        DeclSpace d = (DeclSpace) o;

                                        Error_TypeConflict (name, d.Location);
                                } else
                                        Error_TypeConflict (name);

                                return null;
                        }

                        return ((DeclSpace) o).DefineType ();
                }

                //
                // Resolves a struct during the corlib bootstrap process
                //
                static void BootstrapCorlib_ResolveStruct (TypeContainer root, string name)
                {
                        object o = root.GetDefinition (name);
                        if (o == null){
                                Report.Error (518, "The predefined type `" + name + "' is not defined");
                                return;
                        }

                        if (!(o is Struct)){
                                if (o is DeclSpace){
                                        DeclSpace d = (DeclSpace) o;

                                        Error_TypeConflict (name, d.Location);
                                } else
                                        Error_TypeConflict (name);

                                return;
                        }

                        ((DeclSpace) o).DefineType ();
                }

                //
                // Resolves a struct during the corlib bootstrap process
                //
                static void BootstrapCorlib_ResolveInterface (TypeContainer root, string name)
                {
                        object o = root.GetDefinition (name);
                        if (o == null){
                                Report.Error (518, "The predefined type `" + name + "' is not defined");
                                return;
                        }

                        if (!(o is Interface)){
                                if (o is DeclSpace){
                                        DeclSpace d = (DeclSpace) o;

                                        Error_TypeConflict (name, d.Location);
                                } else
                                        Error_TypeConflict (name);

                                return;
                        }

                        ((DeclSpace) o).DefineType ();
                }

                //
                // Resolves a delegate during the corlib bootstrap process
                //
                static void BootstrapCorlib_ResolveDelegate (TypeContainer root, string name)
                {
                        object o = root.GetDefinition (name);
                        if (o == null){
                                Report.Error (518, "The predefined type `" + name + "' is not defined");
                                Environment.Exit (0);
                        }

                        if (!(o is Delegate)){
                                Error_TypeConflict (name);
                                return;
                        }

                        ((DeclSpace) o).DefineType ();
                }
                

                /// <summary>
                ///    Resolves the core types in the compiler when compiling with --nostdlib
                /// </summary>
                static public void ResolveCore ()
                {
                        TypeContainer root = Tree.Types;

                        TypeManager.object_type = BootstrapCorlib_ResolveClass (root, "System.Object");
                        TypeManager.value_type = BootstrapCorlib_ResolveClass (root, "System.ValueType");
                        TypeManager.attribute_type = BootstrapCorlib_ResolveClass (root, "System.Attribute");
                        
                        string [] interfaces_first_stage = {
                                "System.IComparable", "System.ICloneable",
                                "System.IConvertible",
                                
                                "System.Collections.IEnumerable",
                                "System.Collections.ICollection",
                                "System.Collections.IEnumerator",
                                "System.Collections.IList", 
                                "System.IAsyncResult",
                                "System.IDisposable",
                                
                                "System.Runtime.Serialization.ISerializable",

                                "System.Reflection.IReflect",
                                "System.Reflection.ICustomAttributeProvider"
                        };

                        foreach (string iname in interfaces_first_stage)
                                BootstrapCorlib_ResolveInterface (root, iname);

                        //
                        // These are the base value types
                        //
                        string [] structs_first_stage = {
                                "System.Byte",    "System.SByte",
                                "System.Int16",   "System.UInt16",
                                "System.Int32",   "System.UInt32",
                                "System.Int64",   "System.UInt64",
                        };

                        foreach (string cname in structs_first_stage)
                                BootstrapCorlib_ResolveStruct (root, cname);

                        //
                        // Now, we can load the enumerations, after this point,
                        // we can use enums.
                        //
                        TypeManager.InitEnumUnderlyingTypes ();

                        string [] structs_second_stage = {
                                "System.Single",  "System.Double",
                                "System.Char",    "System.Boolean",
                                "System.Decimal", "System.Void",
                                "System.RuntimeFieldHandle",
                                "System.RuntimeTypeHandle",
                                "System.IntPtr"
                        };
                        
                        foreach (string cname in structs_second_stage)
                                BootstrapCorlib_ResolveStruct (root, cname);
                        
                        //
                        // These are classes that depends on the core interfaces
                        //
                        string [] classes_second_stage = {
                                "System.Reflection.MemberInfo",
                                "System.Type",
                                "System.Exception",

                                //
                                // These are not really important in the order, but they
                                // are used by the compiler later on (typemanager/CoreLookupType-d)
                                //
                                "System.Runtime.CompilerServices.RuntimeHelpers",
                                "System.Reflection.DefaultMemberAttribute",
                                "System.Threading.Monitor",
                                
                                "System.AttributeUsageAttribute",
                                "System.Runtime.InteropServices.DllImportAttribute",
                                "System.Runtime.CompilerServices.MethodImplAttribute",
                                "System.Runtime.InteropServices.MarshalAsAttribute",
                                "System.Diagnostics.ConditionalAttribute",
                                "System.ObsoleteAttribute",
                                "System.ParamArrayAttribute",
                                "System.Security.UnverifiableCodeAttribute",
                                "System.Runtime.CompilerServices.IndexerNameAttribute",
                        };

                        // We must store them here before calling BootstrapCorlib_ResolveDelegate.
                        TypeManager.string_type = BootstrapCorlib_ResolveClass (root, "System.String");
                        TypeManager.enum_type = BootstrapCorlib_ResolveClass (root, "System.Enum");
                        TypeManager.array_type = BootstrapCorlib_ResolveClass (root, "System.Array");
                        TypeManager.multicast_delegate_type = BootstrapCorlib_ResolveClass (root, "System.MulticastDelegate");
                        TypeManager.delegate_type = BootstrapCorlib_ResolveClass (root, "System.Delegate");
                        
                        foreach (string cname in classes_second_stage)
                                BootstrapCorlib_ResolveClass (root, cname);

                        BootstrapCorlib_ResolveDelegate (root, "System.AsyncCallback");
                }
                        
                // <summary>
                //   Closes all open types
                // </summary>
                //
                // <remarks>
                //   We usually use TypeBuilder types.  When we are done
                //   creating the type (which will happen after we have added
                //   methods, fields, etc) we need to "Define" them before we
                //   can save the Assembly
                // </remarks>
                static public void CloseTypes ()
                {
                        TypeContainer root = Tree.Types;
                        
                        ArrayList ifaces = root.Interfaces;

                        if (root.Enums != null)
                                foreach (Enum en in root.Enums)
                                        en.CloseType ();

                        if (attribute_types != null)
                                foreach (TypeContainer tc in attribute_types)
                                        tc.CloseType ();
                        
                        foreach (Interface iface in interface_resolve_order)
                                iface.CloseType ();

                        //
                        // We do this in two passes, first we close the structs,
                        // then the classes, because it seems the code needs it this
                        // way.  If this is really what is going on, we should probably
                        // make sure that we define the structs in order as well.
                        //
                        foreach (TypeContainer tc in type_container_resolve_order){
                                if (tc is Struct && tc.Parent == tree.Types){
                                        tc.CloseType ();
                                }
                        }

                        foreach (TypeContainer tc in type_container_resolve_order){
                                if (!(tc is Struct && tc.Parent == tree.Types))
                                        tc.CloseType ();                                        
                        }
                        
                        if (root.Delegates != null)
                                foreach (Delegate d in root.Delegates)
                                        d.CloseType ();


                        //
                        // If we have a <PrivateImplementationDetails> class, close it
                        //
                        if (impl_details_class != null){
                                impl_details_class.CreateType ();
                        }
                }

                //
                // This idea is from Felix Arrese-Igor
                //
                // Returns : the implicit parent of a composite namespace string
                //   eg. Implicit parent of A.B is A
                //
                static public string ImplicitParent (string ns)
                {
                        int i = ns.LastIndexOf (".");
                        if (i < 0)
                                return null;
                        
                        return ns.Substring (0, i);
                }

                static Type NamespaceLookup (Namespace curr_ns, string name, Location loc)
                {
                        Type t;
                        
                        //
                        // Try in the current namespace and all its implicit parents
                        //
                        for (string ns = curr_ns.Name; ns != null; ns = ImplicitParent (ns)) {
                                t = TypeManager.LookupType (MakeFQN (ns, name));
                                if (t != null)
                                        return t;
                        }
                        
                        //
                        // It's possible that name already is fully qualified. So we do
                        // a simple direct lookup without adding any namespace names
                        //
                        t = TypeManager.LookupType (name); 
                        if (t != null)
                                return t;

                        //
                        // Try the aliases in the current namespace
                        //
                        string alias = sourceBeingCompiled.LookupAlias (name);

                        if (alias != null) {
                                t = TypeManager.LookupType (alias);
                                if (t != null)
                                        return t;

                                t = TypeManager.LookupType (MakeFQN (alias, name));
                                if (t != null)
                                        return t;
                        }
                        
                        for (Namespace ns = curr_ns; ns != null; ns = ns.Parent) {
                                //
                                // Look in the namespace ns
                                //
                                t = TypeManager.LookupType (MakeFQN (ns.Name, name));
                                if (t != null)
                                        return t;
                                
                                //
                                // Then try with the using clauses
                                //

                                ICollection imports_list = sourceBeingCompiled.ImportsTable;

                                if (imports_list == null)
                                        continue;

                                Type match = null;
                                foreach (SourceBeingCompiled.ImportsEntry ue in imports_list) {
                                //TODO: deal with standard modules
                                        match = TypeManager.LookupType (MakeFQN (ue.Name, name));
                                        if (match != null){
                                                if (t != null){
                                                        DeclSpace.Error_AmbiguousTypeReference (loc, name, t, match);
                                                        return null;
                                                }
                                                
                                                t = match;
                                                ue.Used = true;
                                        }
                                }
                                if (t != null)
                                        return t;

                                //
                                // Try with aliases
                                //
                                string a = sourceBeingCompiled.LookupAlias (name);
                                if (a != null) {
                                        t = TypeManager.LookupType (a);
                                        if (t != null)
                                                return t;

                                        t = TypeManager.LookupType (MakeFQN (a, name));
                                        if (t != null)
                                                return t;
                                }
                        }

                        return null;
                }
                
                //
                // Public function used to locate types, this can only
                // be used after the ResolveTree function has been invoked.
                //
                // Returns: Type or null if they type can not be found.
                //
                // Come to think of it, this should be a DeclSpace
                //
                static public Type LookupType (DeclSpace ds, string name, bool silent, Location loc)
                {
                        Type t;

                        if (ds.Cache.Contains (name)){
                                t = (Type) ds.Cache [name];
                                if (t != null)
                                        return t;
                        } else {
                                //
                                // For the case the type we are looking for is nested within this one
                                // or is in any base class
                                //
                                DeclSpace containing_ds = ds;
                                while (containing_ds != null){
                                        Type current_type = containing_ds.TypeBuilder;
                                        
                                        while (current_type != null) {
                                                //
                                                // nested class
                                                //
                                                t = TypeManager.LookupType (current_type.FullName + "." + name);
                                                if (t != null){
                                                        ds.Cache [name] = t;
                                                        return t;
                                                }
                                                
                                                current_type = current_type.BaseType;
                                        }
                                        
                                        containing_ds = containing_ds.Parent;
                                }
                                
                                t = NamespaceLookup (ds.Namespace, name, loc);
                                if (t != null){
                                        ds.Cache [name] = t;
                                        return t;
                                }
                        }

                        if (!silent)
                                Report.Error (30002, loc, "Cannot find type `"+name+"'");
                        
                        return null;
                }

                // <summary>
                //   This is the silent version of LookupType, you can use this
                //   to `probe' for a type
                // </summary>
                static public Type LookupType (TypeContainer tc, string name, Location loc)
                {
                        return LookupType (tc, name, true, loc);
                }

                static public bool IsNamespace (string name)
                {
                        Namespace ns;

                        if (tree.Namespaces != null){
                                ns = (Namespace) tree.Namespaces [name];

                                if (ns != null)
                                        return true;
                        }

                        return false;
                }

                static void Report1530 (Location loc)
                {
                        Report.Error (1530, loc, "Keyword new not allowed for namespace elements");
                }
                
                static public void PopulateCoreType (TypeContainer root, string name)
                {
                        DeclSpace ds = (DeclSpace) root.GetDefinition (name);

                        ds.DefineMembers (root);
                        ds.Define (root);
                }
                
                static public void BootCorlib_PopulateCoreTypes ()
                {
                        TypeContainer root = tree.Types;

                        PopulateCoreType (root, "System.Object");
                        PopulateCoreType (root, "System.ValueType");
                        PopulateCoreType (root, "System.Attribute");
                }
                
                // <summary>
                //   Populates the structs and classes with fields and methods
                // </summary>
                //
                // This is invoked after all interfaces, structs and classes
                // have been defined through `ResolveTree' 
                static public void PopulateTypes ()
                {
                        TypeContainer root = Tree.Types;

                        if (attribute_types != null)
                                foreach (TypeContainer tc in attribute_types)
                                        tc.DefineMembers (root);
                        
                        if (interface_resolve_order != null){
                                foreach (Interface iface in interface_resolve_order)
                                        if ((iface.ModFlags & Modifiers.NEW) == 0)
                                                iface.DefineMembers (root);
                                        else
                                                Report1530 (iface.Location);
                        }


                        if (type_container_resolve_order != null){
                                foreach (TypeContainer tc in type_container_resolve_order) {
                                        // When compiling corlib, these types have already been
                                        // populated from BootCorlib_PopulateCoreTypes ().
                                        if (!RootContext.StdLib &&
                                            ((tc.Name == "System.Object") ||
                                             (tc.Name == "System.Attribute") ||
                                             (tc.Name == "System.ValueType")))
                                                continue;

                                        if ((tc.ModFlags & Modifiers.NEW) == 0)
                                                tc.DefineMembers (root);
                                        else
                                                Report1530 (tc.Location);
                                }
                        }

                        ArrayList delegates = root.Delegates;
                        if (delegates != null){
                                foreach (Delegate d in delegates)
                                        if ((d.ModFlags & Modifiers.NEW) == 0)
                                                d.DefineMembers (root);
                                        else
                                                Report1530 (d.Location);
                        }

                        ArrayList enums = root.Enums;
                        if (enums != null){
                                foreach (Enum en in enums)
                                        if ((en.ModFlags & Modifiers.NEW) == 0)
                                                en.DefineMembers (root);
                                        else
                                                Report1530 (en.Location);
                        }
                }

                static public void DefineTypes ()
                {
                        TypeContainer root = Tree.Types;

                        if (attribute_types != null)
                                foreach (TypeContainer tc in attribute_types)
                                        tc.Define (root);
                        
                        if (interface_resolve_order != null){
                                foreach (Interface iface in interface_resolve_order)
                                        if ((iface.ModFlags & Modifiers.NEW) == 0)
                                                iface.Define (root);
                        }


                        if (type_container_resolve_order != null){
                                foreach (TypeContainer tc in type_container_resolve_order) {
                                        // When compiling corlib, these types have already been
                                        // populated from BootCorlib_PopulateCoreTypes ().
                                        if (!RootContext.StdLib &&
                                            ((tc.Name == "System.Object") ||
                                             (tc.Name == "System.Attribute") ||
                                             (tc.Name == "System.ValueType")))
                                                continue;

                                        if ((tc.ModFlags & Modifiers.NEW) == 0)
                                                tc.Define (root);
                                }
                        }

                        ArrayList delegates = root.Delegates;
                        if (delegates != null){
                                foreach (Delegate d in delegates)
                                        if ((d.ModFlags & Modifiers.NEW) == 0)
                                                d.Define (root);
                        }

                        ArrayList enums = root.Enums;
                        if (enums != null){
                                foreach (Enum en in enums)
                                        if ((en.ModFlags & Modifiers.NEW) == 0)
                                                en.Define (root);
                        }
                }

                static public void EmitCode ()
                {
                        if (attribute_types != null)
                                foreach (TypeContainer tc in attribute_types)
                                        tc.Emit ();

                        CodeGen.EmitGlobalAttributes ();
                        
                        if (type_container_resolve_order != null) {
                                foreach (TypeContainer tc in type_container_resolve_order)
                                        tc.EmitConstants ();
                                
                                foreach (TypeContainer tc in type_container_resolve_order)
                                        tc.Emit ();
                        }
                        
                        if (Unsafe) {
                                if (TypeManager.unverifiable_code_ctor == null) {
                                        Console.WriteLine ("Internal error ! Cannot set unverifiable code attribute.");
                                        return;
                                }
                                
                                CustomAttributeBuilder cb = new CustomAttributeBuilder (TypeManager.unverifiable_code_ctor, new object [0]);
                                CodeGen.ModuleBuilder.SetCustomAttribute (cb);
                        }
                }
                
                //
                // Public Field, used to track which method is the public entry
                // point.
                //
                static public MethodInfo EntryPoint;

                //
                // Track the location of the entry point.
                //
                static public Location EntryPointLocation;

                //
                // These are used to generate unique names on the structs and fields.
                //
                static int field_count;
                
                //
                // Makes an initialized struct, returns the field builder that
                // references the data.  Thanks go to Sergey Chaban for researching
                // how to do this.  And coming up with a shorter mechanism than I
                // was able to figure out.
                //
                // This works but makes an implicit public struct $ArrayType$SIZE and
                // makes the fields point to it.  We could get more control if we did
                // use instead:
                //
                // 1. DefineNestedType on the impl_details_class with our struct.
                //
                // 2. Define the field on the impl_details_class
                //
                static public FieldBuilder MakeStaticData (byte [] data)
                {
                        FieldBuilder fb;
                        int size = data.Length;
                        
                        if (impl_details_class == null)
                                impl_details_class = CodeGen.ModuleBuilder.DefineType (
                                        "<PrivateImplementationDetails>", TypeAttributes.NotPublic, TypeManager.object_type);

                        fb = impl_details_class.DefineInitializedData (
                                "$$field-" + (field_count++), data,
                                FieldAttributes.Static | FieldAttributes.Assembly);
                        
                        return fb;
                }

        }
}