2007-01-10 Chris Toshok <toshok@ximian.com>
[mono.git] / mcs / mcs / support.cs
old mode 100755 (executable)
new mode 100644 (file)
index a4f50c1..b0bb63d
 //
 
 using System;
+using System.IO;
 using System.Text;
 using System.Reflection;
 using System.Collections;
 using System.Reflection.Emit;
+using System.Globalization;
 
 namespace Mono.CSharp {
 
        public interface ParameterData {
                Type ParameterType (int pos);
+               Type [] Types { get; }
                int  Count { get; }
+               bool HasParams { get; }
+               string ParameterName (int pos);
                string ParameterDesc (int pos);
                Parameter.Modifier ParameterModifier (int pos);
+               string GetSignatureForError ();
        }
 
        public class ReflectionParameters : ParameterData {
                ParameterInfo [] pi;
-               bool last_arg_is_params;
-               
-               public ReflectionParameters (ParameterInfo [] pi)
+               Type [] types;
+               int params_idx = -1;
+               bool is_varargs;
+               ParameterData gpd;
+
+               public ReflectionParameters (MethodBase mb)
                {
-                       object [] attrs;
-                       
+                       ParameterInfo [] pi = mb.GetParameters ();
+                       is_varargs = (mb.CallingConvention & CallingConventions.VarArgs) != 0;
+
                        this.pi = pi;
+                       int count = pi.Length;
 
-                       int count = pi.Length-1;
+                       if (count == 0) {
+                               types = Type.EmptyTypes;
+                               return;
+                       }
 
-                       if (count >= 0) {
-                               attrs = pi [count].GetCustomAttributes (TypeManager.param_array_type, true);
+                       types = new Type [count];
+                       for (int i = 0; i < count; i++)
+                               types [i] = pi [i].ParameterType;
+
+                       // TODO: This (if) should be done one level higher to correctly use
+                       // out caching facilities.
+                       MethodBase generic = TypeManager.DropGenericMethodArguments (mb);
+                       if (generic != mb) {
+                               gpd = TypeManager.GetParameterData (generic);
+                               if (gpd.HasParams) {
+                                       for (int i = gpd.Count; i != 0; --i) {
+                                               if ((gpd.ParameterModifier (i-1) & Parameter.Modifier.PARAMS) != 0) {
+                                                       this.params_idx = i-1;
+                                                       break;
+                                               }
+                                       }
+                               }
+                               return;
+                       }
 
-                               if (attrs == null)
-                                       return;
-                               
-                               if (attrs.Length == 0)
+                       //
+                       // So far, the params attribute can be used in C# for the last
+                       // and next to last method parameters.
+                       // If some other language can place it anywhere we will
+                       // have to analyze all parameters and not just last 2.
+                       //
+                       --count;
+                       for (int i = count; i >= 0 && i > count - 2; --i) {
+                               if (!pi [i].ParameterType.IsArray)
+                                       continue;
+
+                               object [] attrs = pi [i].GetCustomAttributes (TypeManager.param_array_type, true);
+                               if (attrs.Length == 1) {
+                                       params_idx = i;
                                        return;
-                               last_arg_is_params = true;
+                               }
                        }
                }
-                      
+
+               public override bool Equals (object obj)
+               {
+                       ReflectionParameters rp = obj as ReflectionParameters;
+                       if (rp == null)
+                               return false;
+
+                       if (Count != rp.Count)
+                               return false;
+
+                       for (int i = 0; i < Count; ++i) {
+                       if (!types [i].Equals (rp.types [i]))
+                               return false;
+                       }
+                       return true;
+               }
+
+               public override int GetHashCode ()
+               {
+                       return base.GetHashCode ();
+               }
+
+               public string GetSignatureForError ()
+               {
+                       StringBuilder sb = new StringBuilder ("(");
+                       for (int i = 0; i < pi.Length; ++i) {
+                               if (i != 0)
+                                       sb.Append (", ");
+                               sb.Append (ParameterDesc (i));
+                       }
+                       if (is_varargs) {
+                               if (pi.Length > 0)
+                                       sb.Append (", ");
+                               sb.Append ("__arglist");
+                       }
+                       sb.Append (')');
+                       return sb.ToString ();
+               }
+
                public Type ParameterType (int pos)
                {
-                       if (last_arg_is_params && pos >= pi.Length - 1)
-                               return pi [pi.Length -1].ParameterType;
-                       else 
-                               return pi [pos].ParameterType;
+                       if (is_varargs && pos >= pi.Length)
+                               return TypeManager.runtime_argument_handle_type;
+
+                       return pi [pos].ParameterType;
+               }
+
+               public string ParameterName (int pos)
+               {
+                       if (gpd != null)
+                               return gpd.ParameterName (pos);
+
+                       if (is_varargs && pos >= pi.Length)
+                               return "__arglist";
+
+                       return pi [pos].Name;
                }
 
                public string ParameterDesc (int pos)
                {
-                       StringBuilder sb = new StringBuilder ();
+                       if (is_varargs && pos >= pi.Length)
+                               return "";
 
-                       if (pi [pos].IsOut)
-                               sb.Append ("out ");
+                       StringBuilder sb = new StringBuilder ();
 
                        if (pi [pos].IsIn)
                                sb.Append ("in ");
 
-                       if (pos >= pi.Length - 1 && last_arg_is_params)
+                       Type partype = ParameterType (pos);
+                       if (partype.IsByRef){
+                               partype = TypeManager.GetElementType (partype);
+                               if (pi [pos].IsOut)
+                                       sb.Append ("out ");
+                               else
+                                       sb.Append ("ref ");
+                       }
+
+                       if (params_idx == pos)
                                sb.Append ("params ");
-                       
-                       sb.Append (TypeManager.CSharpName (ParameterType (pos)));
+
+                       sb.Append (TypeManager.CSharpName (partype).Replace ("&", ""));
 
                        return sb.ToString ();
-                       
                }
 
                public Parameter.Modifier ParameterModifier (int pos)
                {
-                       int len = pi.Length;
-                       
-                       if (pos >= len - 1)
-                               if (last_arg_is_params)
-                                       return Parameter.Modifier.PARAMS;
-                       
+                       if (pos == params_idx)
+                               return Parameter.Modifier.PARAMS;
+                       else if (is_varargs && pos >= pi.Length)
+                               return Parameter.Modifier.ARGLIST;
+
+                       if (gpd != null)
+                               return gpd.ParameterModifier (pos);
+
                        Type t = pi [pos].ParameterType;
-                       if (t.IsByRef)
-                               return Parameter.Modifier.OUT;
-                       
+                       if (t.IsByRef){
+                               if ((pi [pos].Attributes & (ParameterAttributes.Out|ParameterAttributes.In)) == ParameterAttributes.Out)
+                                       return Parameter.Modifier.OUT;
+                               else
+                                       return Parameter.Modifier.REF;
+                       }
+
                        return Parameter.Modifier.NONE;
                }
 
                public int Count {
-                       get {
-                               return pi.Length;
-                       }
+                       get { return is_varargs ? pi.Length + 1 : pi.Length; }
                }
-               
-       }
 
-       public class InternalParameters : ParameterData {
-               Type [] param_types;
-
-               Parameters parameters;
-               
-               public InternalParameters (Type [] param_types, Parameters parameters)
-               {
-                       this.param_types = param_types;
-                       this.parameters = parameters;
+               public bool HasParams {
+                       get { return params_idx != -1; }
                }
 
-               public InternalParameters (DeclSpace ds, Parameters parameters)
-                       : this (parameters.GetParameterInfo (ds), parameters)
-               {
+               public Type[] Types {
+                       get { return types; }
                }
+       }
 
-               public int Count {
-                       get {
-                               if (param_types == null)
-                                       return 0;
+#if GMCS_SOURCE
+       public class ReflectionConstraints : GenericConstraints
+       {
+               GenericParameterAttributes attrs;
+               Type base_type;
+               Type class_constraint;
+               Type[] iface_constraints;
+               string name;
 
-                               return param_types.Length;
-                       }
+               public static GenericConstraints GetConstraints (Type t)
+               {
+                       Type [] constraints = t.GetGenericParameterConstraints ();
+                       GenericParameterAttributes attrs = t.GenericParameterAttributes;
+                       if (constraints.Length == 0 && attrs == GenericParameterAttributes.None)
+                               return null;
+                       return new ReflectionConstraints (t.Name, constraints, attrs);
                }
 
-               public Type ParameterType (int pos)
+               private ReflectionConstraints (string name, Type [] constraints, GenericParameterAttributes attrs)
                {
-                       if (param_types == null)
-                               return null;
+                       this.name = name;
+                       this.attrs = attrs;
 
-                       Parameter [] fixed_pars = parameters.FixedParameters;
-                       if (fixed_pars != null){
-                               int len = fixed_pars.Length;
-                               if (pos < len)
-                                       return parameters.FixedParameters [pos].ParameterType;
-                               else 
-                                       return parameters.ArrayParameter.ParameterType;
+                       if ((constraints.Length > 0) && !constraints [0].IsInterface) {
+                               class_constraint = constraints [0];
+                               iface_constraints = new Type [constraints.Length - 1];
+                               Array.Copy (constraints, 1, iface_constraints, 0, constraints.Length - 1);
                        } else
-                               return parameters.ArrayParameter.ParameterType;
+                               iface_constraints = constraints;
+
+                       if (HasValueTypeConstraint)
+                               base_type = TypeManager.value_type;
+                       else if (class_constraint != null)
+                               base_type = class_constraint;
+                       else
+                               base_type = TypeManager.object_type;
                }
 
-               public string ParameterDesc (int pos)
-               {
-                       string tmp = String.Empty;
-                       Parameter p;
+               public override string TypeParameter {
+                       get { return name; }
+               }
 
-                       if (pos >= parameters.FixedParameters.Length)
-                               p = parameters.ArrayParameter;
-                       else
-                               p = parameters.FixedParameters [pos];
-                       
-                       if (p.ModFlags == Parameter.Modifier.REF)
-                               tmp = "ref ";
-                       else if (p.ModFlags == Parameter.Modifier.OUT)
-                               tmp = "out ";
-                       else if (p.ModFlags == Parameter.Modifier.PARAMS)
-                               tmp = "params ";
+               public override GenericParameterAttributes Attributes {
+                       get { return attrs; }
+               }
 
-                       Type t = ParameterType (pos);
+               public override Type ClassConstraint {
+                       get { return class_constraint; }
+               }
 
-                       return tmp + TypeManager.CSharpName (t);
+               public override Type EffectiveBaseClass {
+                       get { return base_type; }
                }
 
-               public Parameter.Modifier ParameterModifier (int pos)
-               {
-                       if (parameters.FixedParameters == null) {
-                               if (parameters.ArrayParameter != null) 
-                                       return parameters.ArrayParameter.ModFlags;
-                               else
-                                       return Parameter.Modifier.NONE;
-                       }
-                       
-                       if (pos >= parameters.FixedParameters.Length)
-                               return parameters.ArrayParameter.ModFlags;
-                       else {
-                               Parameter.Modifier m = parameters.FixedParameters [pos].ModFlags;
-
-                               //
-                               // We use a return value of "OUT" for "reference" parameters.
-                               // both out and ref flags in the source map to reference parameters.
-                               //
-                               if (m == Parameter.Modifier.OUT || m == Parameter.Modifier.REF)
-                                       return Parameter.Modifier.OUT;
-                               
-                               return Parameter.Modifier.NONE;
-                       }
+               public override Type[] InterfaceConstraints {
+                       get { return iface_constraints; }
                }
-               
        }
+#endif
 
        class PtrHashtable : Hashtable {
-               class PtrComparer : IComparer {
+               sealed class PtrComparer : IComparer {
+                       private PtrComparer () {}
+
+                       public static PtrComparer Instance = new PtrComparer ();
+
                        public int Compare (object x, object y)
                        {
                                if (x == y)
@@ -197,44 +280,227 @@ namespace Mono.CSharp {
                                        return 1;
                        }
                }
-               
+
                public PtrHashtable ()
                {
-                       comparer = new PtrComparer ();
+                       comparer = PtrComparer.Instance;
                }
        }
 
-       //
-       // Compares member infos based on their name and
-       // also allows one argument to be a string
-       //
-       class MemberInfoCompare : IComparer {
+       /*
+        * Hashtable whose keys are character arrays with the same length
+        */
+       class CharArrayHashtable : Hashtable {
+               sealed class ArrComparer : IComparer {
+                       private int len;
 
-               public int Compare (object a, object b)
-               {
-                       if (a == null || b == null){
-                               Console.WriteLine ("Invalid information passed");
-                               throw new Exception ();
+                       public ArrComparer (int len) {
+                               this.len = len;
+                       }
+
+                       public int Compare (object x, object y)
+                       {
+                               char[] a = (char[])x;
+                               char[] b = (char[])y;
+
+                               for (int i = 0; i < len; ++i)
+                                       if (a [i] != b [i])
+                                               return 1;
+                               return 0;
                        }
-                       
-                       if (a is string)
-                               return String.Compare ((string) a, ((MemberInfo)b).Name);
+               }
+
+               private int len;
+
+               protected override int GetHash (Object key)
+               {
+                       char[] arr = (char[])key;
+                       int h = 0;
+
+                       for (int i = 0; i < len; ++i)
+                               h = (h << 5) - h + arr [i];
 
-                       if (b is string)
-                               return String.Compare (((MemberInfo)a).Name, (string) b);
+                       return h;
+               }
 
-                       return String.Compare (((MemberInfo)a).Name, ((MemberInfo)b).Name);
+               public CharArrayHashtable (int len)
+               {
+                       this.len = len;
+                       comparer = new ArrComparer (len);
                }
        }
 
        struct Pair {
                public object First;
                public object Second;
-               
+
                public Pair (object f, object s)
                {
                        First = f;
                        Second = s;
                }
        }
+
+       /// <summary>
+       ///   This is a wrapper around StreamReader which is seekable backwards
+       ///   within a window of around 2048 chars.
+       /// </summary>
+       public class SeekableStreamReader
+       {
+               public SeekableStreamReader (StreamReader reader)
+               {
+                       this.reader = reader;
+                       this.buffer = new char [AverageReadLength * 3];
+
+                       // Let the StreamWriter autodetect the encoder
+                       reader.Peek ();
+               }
+
+               public SeekableStreamReader (Stream stream, Encoding encoding)
+                       : this (new StreamReader (stream, encoding, true))
+               { }
+
+               StreamReader reader;
+
+               private const int AverageReadLength = 1024;
+
+               char[] buffer;
+               int buffer_start;       // in chars
+               int char_count;         // count buffer[] valid characters
+               int pos;                // index into buffer[]
+
+               /// <remarks>
+               ///   This value corresponds to the current position in a stream of characters.
+               ///   The StreamReader hides its manipulation of the underlying byte stream and all
+               ///   character set/decoding issues.  Thus, we cannot use this position to guess at
+               ///   the corresponding position in the underlying byte stream even though there is
+               ///   a correlation between them.
+               /// </remarks>
+               public int Position {
+                       get { return buffer_start + pos; }
+
+                       set {
+                               if (value < buffer_start || value > buffer_start + char_count)
+                                       throw new InternalErrorException ("can't seek that far back: " + (pos - value));
+                               pos = value - buffer_start;
+                       }
+               }
+
+               private bool ReadBuffer ()
+               {
+                       int slack = buffer.Length - char_count;
+                       if (slack <= AverageReadLength / 2) {
+                               // shift the buffer to make room for AverageReadLength number of characters
+                               int shift = AverageReadLength - slack;
+                               Array.Copy (buffer, shift, buffer, 0, char_count - shift);
+                               pos -= shift;
+                               char_count -= shift;
+                               buffer_start += shift;
+                               slack += shift;         // slack == AverageReadLength
+                       }
+
+                       int chars_read = reader.Read (buffer, char_count, slack);
+                       char_count += chars_read;
+
+                       return pos < char_count;
+               }
+
+               public int Peek ()
+               {
+                       if ((pos >= char_count) && !ReadBuffer ())
+                               return -1;
+
+                       return buffer [pos];
+               }
+
+               public int Read ()
+               {
+                       if ((pos >= char_count) && !ReadBuffer ())
+                               return -1;
+
+                       return buffer [pos++];
+               }
+       }
+
+       public class DoubleHash {
+               const int DEFAULT_INITIAL_BUCKETS = 100;
+
+               public DoubleHash () : this (DEFAULT_INITIAL_BUCKETS) {}
+
+               public DoubleHash (int size)
+               {
+                       count = size;
+                       buckets = new Entry [size];
+               }
+
+               int count;
+               Entry [] buckets;
+               int size = 0;
+
+               class Entry {
+                       public object key1;
+                       public object key2;
+                       public int hash;
+                       public object value;
+                       public Entry next;
+
+                       public Entry (object key1, object key2, int hash, object value, Entry next)
+                       {
+                               this.key1 = key1;
+                               this.key2 = key2;
+                               this.hash = hash;
+                               this.next = next;
+                               this.value = value;
+                       }
+               }
+
+               public bool Lookup (object a, object b, out object res)
+               {
+                       int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
+
+                       for (Entry e = buckets [h % count]; e != null; e = e.next) {
+                               if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b)) {
+                                       res = e.value;
+                                       return true;
+                               }
+                       }
+                       res = null;
+                       return false;
+               }
+
+               public void Insert (object a, object b, object value)
+               {
+                       // Is it an existing one?
+
+                       int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
+
+                       for (Entry e = buckets [h % count]; e != null; e = e.next) {
+                               if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b))
+                                       e.value = value;
+                       }
+
+                       int bucket = h % count;
+                       buckets [bucket] = new Entry (a, b, h, value, buckets [bucket]);
+
+                       // Grow whenever we double in size
+                       if (size++ == count) {
+                               count <<= 1;
+                               count ++;
+
+                               Entry [] newBuckets = new Entry [count];
+                               foreach (Entry root in buckets) {
+                                       Entry e = root;
+                                       while (e != null) {
+                                               int newLoc = e.hash % count;
+                                               Entry n = e.next;
+                                               e.next = newBuckets [newLoc];
+                                               newBuckets [newLoc] = e;
+                                               e = n;
+                                       }
+                               }
+
+                               buckets = newBuckets;
+                       }
+               }
+       }
 }