mcs/mcs/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 System.Diagnostics.SymbolStore;
  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 {
  24                 public readonly string Name;
  25                 public readonly string Path;
  26                 public readonly int Index;
  27                 public ISymbolDocumentWriter SymbolDocument;
  28
  29                 public SourceFile (string name, string path, int index)
  30                 {
  31                         this.Index = index;
  32                         this.Name = name;
  33                         this.Path = path;
  34                 }
  35         }
  36
  37         /// <summary>
  38         ///   Keeps track of the location in the program
  39         /// </summary>
  40         ///
  41         /// <remarks>
  42         ///   This uses a compact representation and a couple of auxiliary
  43         ///   structures to keep track of tokens to (file,line) mappings.
  44         ///
  45         ///   We could probably also keep track of columns by storing those
  46         ///   in 8 bits (and say, map anything after char 255 to be `255+').
  47         /// </remarks>
  48         public struct Location {
  49                 public int token;
  50
  51                 static ArrayList source_list;
  52                 static Hashtable source_files;
  53                 static int source_bits;
  54                 static int source_mask;
  55                 static int source_count;
  56                 static int current_source;
  57
  58                 public readonly static Location Null;
  59
  60                 static Location ()
  61                 {
  62                         source_files = new Hashtable ();
  63                         source_list = new ArrayList ();
  64                         current_source = 0;
  65                         Null.token = 0;
  66                 }
  67
  68                 // <summary>
  69                 //   This must be called before parsing/tokenizing any files.
  70                 // </summary>
  71                 static public void AddFile (string name)
  72                 {
  73                         string path = Path.GetFullPath (name);
  74
  75                         if (source_files.Contains (path)){
  76                                 Report.Error (
  77                                         1516,
  78                                         "Source file `" + name + "' specified multiple times");
  79                                 Environment.Exit (1);
  80                         }
  81
  82                         source_files.Add (path, ++source_count);
  83                         source_list.Add (new SourceFile (name, path, source_count));
  84                 }
  85
  86                 static public SourceFile[] SourceFiles {
  87                         get {
  88                                 SourceFile[] retval = new SourceFile [source_list.Count];
  89                                 source_list.CopyTo (retval, 0);
  90                                 return retval;
  91                         }
  92                 }
  93
  94                 static int log2 (int number)
  95                 {
  96                         int bits = 0;
  97                         while (number > 0) {
  98                                 bits++;
  99                                 number /= 2;
 100                         }
 101
 102                         return bits;
 103                 }
 104
 105                 // <summary>
 106                 //   After adding all source files we want to compile with AddFile(), this method
 107                 //   must be called to `reserve' an appropriate number of bits in the token for the
 108                 //   source file.  We reserve some extra space for files we encounter via #line
 109                 //   directives while parsing.
 110                 // </summary>
 111                 static public void Initialize ()
 112                 {
 113                         source_bits = log2 (source_list.Count) + 2;
 114                         source_mask = (1 << source_bits) - 1;
 115                 }
 116
 117                 // <remarks>
 118                 //   This is used when we encounter a #line preprocessing directive.
 119                 // </remarks>
 120                 static public SourceFile LookupFile (string name)
 121                 {
 122                         string path = Path.GetFullPath (name);
 123
 124                         if (!source_files.Contains (path)) {
 125                                 if (source_count >= (1 << source_bits))
 126                                         return new SourceFile (name, path, 0);
 127
 128                                 source_files.Add (path, ++source_count);
 129                                 SourceFile retval = new SourceFile (name, path, source_count);
 130                                 source_list.Add (retval);
 131                                 return retval;
 132                         }
 133
 134                         int index = (int) source_files [path];
 135                         return (SourceFile) source_list [index - 1];
 136                 }
 137
 138                 static public void Push (SourceFile file)
 139                 {
 140                         current_source = file.Index;
 141                 }
 142
 143                 // <remarks>
 144                 //   If we're compiling with debugging support, this is called between parsing and
 145                 //   code generation to register all the source files with the symbol writer.           //
 146                 // </remarks>
 147                 static public void DefineSymbolDocuments (SymbolWriter symwriter)
 148                 {
 149                         foreach (SourceFile file in source_list)
 150                                 file.SymbolDocument = symwriter.DefineDocument (file.Path);
 151                 }
 152
 153                 public Location (int row)
 154                 {
 155                         if (row < 0)
 156                                 token = 0;
 157                         else
 158                                 token = current_source + (row << source_bits);
 159                 }
 160
 161                 public override string ToString ()
 162                 {
 163                         return Name + ": (" + Row + ")";
 164                 }
 165
 166                 /// <summary>
 167                 ///   Whether the Location is Null
 168                 /// </summary>
 169                 static public bool IsNull (Location l)
 170                 {
 171                         return l.token == 0;
 172                 }
 173
 174                 public string Name {
 175                         get {
 176                                 int index = token & source_mask;
 177                                 if ((token == 0) || (index == 0))
 178                                         return "Internal";
 179
 180                                 SourceFile file = (SourceFile) source_list [index - 1];
 181                                 return file.Name;
 182                         }
 183                 }
 184
 185                 public int Row {
 186                         get {
 187                                 if (token == 0)
 188                                         return 1;
 189
 190                                 return token >> source_bits;
 191                         }
 192                 }
 193
 194                 public int File {
 195                         get {
 196                                 return token & source_mask;
 197                         }
 198                 }
 199
 200                 // The ISymbolDocumentWriter interface is used by the symbol writer to
 201                 // describe a single source file - for each source file there's exactly
 202                 // one corresponding ISymbolDocumentWriter instance.
 203                 //
 204                 // This class has an internal hash table mapping source document names
 205                 // to such ISymbolDocumentWriter instances - so there's exactly one
 206                 // instance per document.
 207                 //
 208                 // This property returns the ISymbolDocumentWriter instance which belongs
 209                 // to the location's source file.
 210                 //
 211                 // If we don't have a symbol writer, this property is always null.
 212                 public ISymbolDocumentWriter SymbolDocument {
 213                         get {
 214                                 int index = token & source_mask;
 215                                 if (index == 0)
 216                                         return null;
 217                                 SourceFile file = (SourceFile) source_list [index - 1];
 218                                 return file.SymbolDocument;
 219                         }
 220                 }
 221         }
 222 }