mcs/tools/linker/Mono.Linker.Steps/SweepStep.cs

   1 //
   2 // SweepStep.cs
   3 //
   4 // Author:
   5 //   Jb Evain (jbevain@gmail.com)
   6 //
   7 // (C) 2006 Jb Evain
   8 // (C) 2007 Novell, Inc.
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Collections;
  31 using System.Collections.Generic;
  32 using Mono.Cecil;
  33
  34 namespace Mono.Linker.Steps {
  35
  36         public class SweepStep : BaseStep {
  37
  38                 AssemblyDefinition [] assemblies;
  39
  40                 protected override void Process ()
  41                 {
  42                         assemblies = Context.GetAssemblies ();
  43                         foreach (var assembly in assemblies)
  44                                 SweepAssembly (assembly);
  45                 }
  46
  47                 void SweepAssembly (AssemblyDefinition assembly)
  48                 {
  49                         if (Annotations.GetAction (assembly) != AssemblyAction.Link)
  50                                 return;
  51
  52                         if (!IsMarkedAssembly (assembly)) {
  53                                 RemoveAssembly (assembly);
  54                                 return;
  55                         }
  56
  57                         var types = assembly.MainModule.Types;
  58                         var cloned_types = new List<TypeDefinition> (types);
  59
  60                         types.Clear ();
  61
  62                         foreach (TypeDefinition type in cloned_types) {
  63                                 if (Annotations.IsMarked (type)) {
  64                                         SweepType (type);
  65                                         types.Add (type);
  66                                         continue;
  67                                 }
  68
  69                                 if (type.Name == "<Module>")
  70                                         types.Add (type);
  71                         }
  72                 }
  73
  74                 bool IsMarkedAssembly (AssemblyDefinition assembly)
  75                 {
  76                         return Annotations.IsMarked (assembly.MainModule);
  77                 }
  78
  79                 void RemoveAssembly (AssemblyDefinition assembly)
  80                 {
  81                         Annotations.SetAction (assembly, AssemblyAction.Delete);
  82
  83                         SweepReferences (assembly);
  84                 }
  85
  86                 void SweepReferences (AssemblyDefinition target)
  87                 {
  88                         foreach (var assembly in assemblies)
  89                                 SweepReferences (assembly, target);
  90                 }
  91
  92                 void SweepReferences (AssemblyDefinition assembly, AssemblyDefinition target)
  93                 {
  94                         var references = assembly.MainModule.AssemblyReferences;
  95                         for (int i = 0; i < references.Count; i++) {
  96                                 var reference = references [i];
  97                                 if (!AreSameReference (reference, target.Name))
  98                                         continue;
  99
 100                                 references.RemoveAt (i);
 101                                 return;
 102                         }
 103                 }
 104
 105                 static ICollection Clone (ICollection collection)
 106                 {
 107                         return new ArrayList (collection);
 108                 }
 109
 110                 void SweepType (TypeDefinition type)
 111                 {
 112                         if (type.HasFields)
 113                                 SweepCollection (type.Fields);
 114
 115                         if (type.HasMethods)
 116                                 SweepCollection (type.Methods);
 117
 118                         if (type.HasNestedTypes)
 119                                 SweepNestedTypes (type);
 120                 }
 121
 122                 void SweepNestedTypes (TypeDefinition type)
 123                 {
 124                         for (int i = 0; i < type.NestedTypes.Count; i++) {
 125                                 var nested = type.NestedTypes [i];
 126                                 if (Annotations.IsMarked (nested)) {
 127                                         SweepType (nested);
 128                                 } else {
 129                                         type.NestedTypes.RemoveAt (i--);
 130                                 }
 131                         }
 132                 }
 133
 134                 void SweepCollection (IList list)
 135                 {
 136                         for (int i = 0; i < list.Count; i++)
 137                                 if (!Annotations.IsMarked ((IMetadataTokenProvider) list [i]))
 138                                         list.RemoveAt (i--);
 139                 }
 140
 141                 static bool AreSameReference (AssemblyNameReference a, AssemblyNameReference b)
 142                 {
 143                         if (a == b)
 144                                 return true;
 145
 146                         if (a.Name != b.Name)
 147                                 return false;
 148
 149                         if (a.Version != b.Version)
 150                                 return false;
 151
 152                         return true;
 153                 }
 154         }
 155 }