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