mcs/bmcs/location.cs

   1 //
   2 // location.cs: Keeps track of the location of source code entity
   3 //
   4 // Author:
   5 //   Miguel de Icaza
   6 //
   7 // (C) 2001 Ximian, Inc.
   8 //
   9
  10 using System;
  11 using System.IO;
  12 using System.Collections;
  13 using Mono.CompilerServices.SymbolWriter;
  14
  15 namespace Mono.CSharp {
  16         /// <summary>
  17         ///   This is one single source file.
  18         /// </summary>
  19         /// <remarks>
  20         ///   This is intentionally a class and not a struct since we need
  21         ///   to pass this by reference.
  22         /// </remarks>
  23         public sealed class SourceFile : ISourceFile {
  24                 public readonly string Name;
  25                 public readonly string Path;
  26                 public readonly int Index;
  27                 public SourceFileEntry SourceFileEntry;
  28                 public bool HasLineDirective;
  29
  30                 public SourceFile (string name, string path, int index)
  31                 {
  32                         this.Index = index;
  33                         this.Name = name;
  34                         this.Path = path;
  35                 }
  36
  37                 SourceFileEntry ISourceFile.Entry {
  38                         get { return SourceFileEntry; }
  39                 }
  40
  41                 public override string ToString ()
  42                 {
  43                         return String.Format ("SourceFile ({0}:{1}:{2}:{3})",
  44                                               Name, Path, Index, SourceFileEntry);
  45                 }
  46         }
  47
  48         /// <summary>
  49         ///   Keeps track of the location in the program
  50         /// </summary>
  51         ///
  52         /// <remarks>
  53         ///   This uses a compact representation and a couple of auxiliary
  54         ///   structures to keep track of tokens to (file,line) mappings.
  55         ///
  56         ///   We could probably also keep track of columns by storing those
  57         ///   in 8 bits (and say, map anything after char 255 to be `255+').
  58         /// </remarks>
  59         public struct Location {
  60                 public int token;
  61
  62                 static ArrayList source_list;
  63                 static Hashtable source_files;
  64                 static int source_bits;
  65                 static int source_mask;
  66                 static int source_count;
  67                 static int current_source;
  68
  69                 public readonly static Location Null;
  70
  71                 static Location ()
  72                 {
  73                         source_files = new Hashtable ();
  74                         source_list = new ArrayList ();
  75                         current_source = 0;
  76                         Null.token = 0;
  77                 }
  78
  79                 // <summary>
  80                 //   This must be called before parsing/tokenizing any files.
  81                 // </summary>
  82                 static public void AddFile (string name)
  83                 {
  84                         string path = Path.GetFullPath (name);
  85
  86                         if (source_files.Contains (path)){
  87                                 int id = (int) source_files [path];
  88                                 string other_name = ((SourceFile) source_list [id - 1]).Name;
  89                                 if (name.Equals (other_name))
  90                                         Report.Warning (2002, "Source file '{0}' specified multiple times", name);
  91                                 else
  92                                         Report.Warning (2002, "Source filenames '{0}' and '{1}' both refer to the same file: {2}", name, other_name, path);
  93                                 return;
  94                         }
  95
  96                         source_files.Add (path, ++source_count);
  97                         source_list.Add (new SourceFile (name, path, source_count));
  98                 }
  99
 100                 static public SourceFile[] SourceFiles {
 101                         get {
 102                                 SourceFile[] retval = new SourceFile [source_list.Count];
 103                                 source_list.CopyTo (retval, 0);
 104                                 return retval;
 105                         }
 106                 }
 107
 108                 static int log2 (int number)
 109                 {
 110                         int bits = 0;
 111                         while (number > 0) {
 112                                 bits++;
 113                                 number /= 2;
 114                         }
 115
 116                         return bits;
 117                 }
 118
 119                 // <summary>
 120                 //   After adding all source files we want to compile with AddFile(), this method
 121                 //   must be called to `reserve' an appropriate number of bits in the token for the
 122                 //   source file.  We reserve some extra space for files we encounter via #line
 123                 //   directives while parsing.
 124                 // </summary>
 125                 static public void Initialize ()
 126                 {
 127                         source_bits = log2 (source_list.Count) + 2;
 128                         source_mask = (1 << source_bits) - 1;
 129                 }
 130
 131                 // <remarks>
 132                 //   This is used when we encounter a #line preprocessing directive.
 133                 // </remarks>
 134                 static public SourceFile LookupFile (string name)
 135                 {
 136                         string path = name == "" ? "" : Path.GetFullPath (name);
 137
 138                         if (!source_files.Contains (path)) {
 139                                 if (source_count >= (1 << source_bits))
 140                                         return new SourceFile (name, path, 0);
 141
 142                                 source_files.Add (path, ++source_count);
 143                                 SourceFile retval = new SourceFile (name, path, source_count);
 144                                 source_list.Add (retval);
 145                                 return retval;
 146                         }
 147
 148                         int index = (int) source_files [path];
 149                         return (SourceFile) source_list [index - 1];
 150                 }
 151
 152 /*
 153                 static public void Push (SourceFile file)
 154                 {
 155                         current_source = file.Index;
 156                 }
 157 */
 158
 159                 // <remarks>
 160                 //   If we're compiling with debugging support, this is called between parsing
 161                 //   and code generation to register all the source files with the
 162                 //   symbol writer.
 163                 // </remarks>
 164                 static public void DefineSymbolDocuments (SymbolWriter symwriter)
 165                 {
 166                         foreach (SourceFile file in source_list) {
 167                                 file.SourceFileEntry = symwriter.DefineDocument (file.Path);
 168                         }
 169                 }
 170
 171                 public Location (int row)
 172                 {
 173                         if (row < 0)
 174                                 token = 0;
 175                         else
 176                                 token = current_source + (row << source_bits);
 177                 }
 178
 179                 public override string ToString ()
 180                 {
 181                         return Name + ": (" + Row + ")";
 182                 }
 183
 184                 /// <summary>
 185                 ///   Whether the Location is Null
 186                 /// </summary>
 187                 static public bool IsNull (Location l)
 188                 {
 189                         return l.token == 0;
 190                 }
 191
 192                 public string Name {
 193                         get {
 194                                 int index = token & source_mask;
 195                                 if ((token == 0) || (index == 0))
 196                                         return "Internal";
 197
 198                                 SourceFile file = (SourceFile) source_list [index - 1];
 199                                 return file.Name;
 200                         }
 201                 }
 202
 203                 public int Row {
 204                         get {
 205                                 if (token == 0)
 206                                         return 1;
 207
 208                                 return token >> source_bits;
 209                         }
 210                 }
 211
 212                 public int File {
 213                         get {
 214                                 return token & source_mask;
 215                         }
 216                 }
 217
 218                 // The ISymbolDocumentWriter interface is used by the symbol writer to
 219                 // describe a single source file - for each source file there's exactly
 220                 // one corresponding ISymbolDocumentWriter instance.
 221                 //
 222                 // This class has an internal hash table mapping source document names
 223                 // to such ISymbolDocumentWriter instances - so there's exactly one
 224                 // instance per document.
 225                 //
 226                 // This property returns the ISymbolDocumentWriter instance which belongs
 227                 // to the location's source file.
 228                 //
 229                 // If we don't have a symbol writer, this property is always null.
 230                 public SourceFile SourceFile {
 231                         get {
 232                                 int index = token & source_mask;
 233                                 if (index == 0)
 234                                         return null;
 235                                 return (SourceFile) source_list [index - 1];
 236                         }
 237                 }
 238         }
 239 }