1    :  // Copyright 2014 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  // Declares a transform for converting non-relocation reference types in code
  16    :  // blocks to equivalent relocation references. Legacy transformations that have
  17    :  // not been updated to fully support COFF may insert these kinds of references
  18    :  // when generating or altering code.
  19    :  //
  20    :  // TODO(chrisha): Remove this eventually. It appears that *all* references use
  21    :  //     the RELOC_REF_BIT when processing COFF files, and that reference types
  22    :  //     are never mixed. Thus, the bit basically only indicates that we are
  23    :  //     dealing with a COFF file, which is already known.
  24    :  
  25    :  #ifndef SYZYGY_PE_TRANSFORMS_COFF_CONVERT_LEGACY_CODE_REFERENCES_TRANSFORM_H_
  26    :  #define SYZYGY_PE_TRANSFORMS_COFF_CONVERT_LEGACY_CODE_REFERENCES_TRANSFORM_H_
  27    :  
  28    :  #include "syzygy/block_graph/transforms/named_transform.h"
  29    :  
  30    :  namespace pe {
  31    :  namespace transforms {
  32    :  
  33    :  // A transform for converting non-relocation reference types in code blocks
  34    :  // to equivalent relocation references.
  35    :  class CoffConvertLegacyCodeReferencesTransform
  36    :      : public block_graph::transforms::NamedBlockGraphTransformImpl<
  37    :            CoffConvertLegacyCodeReferencesTransform> {
  38    :   public:
  39    :    typedef block_graph::BlockGraph BlockGraph;
  40    :    typedef block_graph::TransformPolicyInterface TransformPolicyInterface;
  41    :  
  42    :    // Construct a CoffConvertLegacyCodeReferencesTransform.
  43  E :    CoffConvertLegacyCodeReferencesTransform() {}
  44    :  
  45    :    // Perform the transform. Convert legacy references in all code blocks.
  46    :    // @param policy the policy object restricting how the transform is applied.
  47    :    // @param block_graph the BlockGraph to transform.
  48    :    // @param headers_block the block containing the headers. This is currently
  49    :    //     unused.
  50    :    // @returns true on success, false otherwise.
  51    :    virtual bool TransformBlockGraph(
  52    :        const TransformPolicyInterface* policy,
  53    :        BlockGraph* block_graph,
  54    :        BlockGraph::Block* /* headers_block */) OVERRIDE;
  55    :  
  56    :    // The name of this transform.
  57    :    static const char kTransformName[];
  58    :  
  59    :   private:
  60    :    DISALLOW_COPY_AND_ASSIGN(CoffConvertLegacyCodeReferencesTransform);
  61    :  };
  62    :  
  63    :  }  // namespace transforms
  64    :  }  // namespace pe
  65    :  
  66    :  #endif  // SYZYGY_PE_TRANSFORMS_COFF_CONVERT_LEGACY_CODE_REFERENCES_TRANSFORM_H_