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Diffstat (limited to 'third_party/courgette/ensemble.h')
| -rw-r--r-- | third_party/courgette/ensemble.h | 257 |
1 files changed, 0 insertions, 257 deletions
diff --git a/third_party/courgette/ensemble.h b/third_party/courgette/ensemble.h deleted file mode 100644 index 7602c3f..0000000 --- a/third_party/courgette/ensemble.h +++ /dev/null @@ -1,257 +0,0 @@ -// Copyright (c) 2009 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// The main idea in Courgette is to do patching *under a tranformation*. The
-// input is transformed into a new representation, patching occurs in the new
-// repesentation, and then the tranform is reversed to get the patched data.
-//
-// The idea is applied to pieces (or 'Elements') of the whole (or 'Ensemble').
-// Each of the elements has to go through the same set of steps in lock-step,
-// but there may be many different kinds of elements, which have different
-// transformation.
-//
-// This file declares all the main types involved in creating and applying a
-// patch with this structure.
-
-#ifndef COURGETTE_ENSEMBLE_H_
-#define COURGETTE_ENSEMBLE_H_
-
-#include <vector>
-#include <string>
-
-#include "base/basictypes.h"
-
-#include "third_party/courgette/courgette.h"
-#include "third_party/courgette/region.h"
-#include "third_party/courgette/streams.h"
-
-namespace courgette {
-
-// Forward declarations:
-class Ensemble;
-class PEInfo;
-
-// An Element is a region of an Ensemble with an identifyable kind.
-//
-class Element {
- public:
- enum Kind { WIN32_X86_WITH_CODE, WIN32_NOCODE };
-
- virtual ~Element() {}
-
- Kind kind() const { return kind_; }
- const Region& region() const { return region_; }
-
- // The name is used only for debugging and logging.
- virtual std::string Name() const;
-
- // Returns the byte position of this Element relative to the start of
- // containing Ensemble.
- size_t offset_in_ensemble() const;
-
- // Some subclasses of Element might have a PEInfo.
- virtual PEInfo* GetPEInfo() const { return NULL; }
-
- protected:
- Element(Kind kind, Ensemble* ensemble, const Region& region);
-
- private:
- Kind kind_;
- Ensemble* ensemble_;
- Region region_;
-
- DISALLOW_COPY_AND_ASSIGN(Element);
-};
-
-
-class Ensemble {
- public:
- Ensemble(const Region& region, const char* name)
- : region_(region), name_(name) {}
- ~Ensemble();
-
- const Region& region() const { return region_; }
- const std::string& name() const { return name_; }
-
- // Scans the region to find Elements within the region().
- Status FindEmbeddedElements();
-
- // Returns the elements found by 'FindEmbeddedElements'.
- const std::vector<Element*>& elements() const { return elements_; }
-
-
- private:
- Region region_; // The memory, owned by caller, containing the
- // Ensemble's data.
- std::string name_; // A debugging/logging name for the Ensemble.
-
- std::vector<Element*> elements_; // Embedded elements discovered.
- std::vector<Element*> owned_elements_; // For deallocation.
-
- DISALLOW_COPY_AND_ASSIGN(Ensemble);
-};
-
-inline size_t Element::offset_in_ensemble() const {
- return region().start() - ensemble_->region().start();
-}
-
-// The 'CourgettePatchFile' is class is a 'namespace' for the constants that
-// appear in a Courgette patch file.
-struct CourgettePatchFile {
- //
- // The Courgette patch format interleaves the data for N embedded Elements.
- //
- // Format of a patch file:
- // header:
- // magic
- // version
- // source-checksum
- // target-checksum
- // multiple-streams:
- // stream 0:
- // number-of-transformed-elements (N) - varint32
- // transformation-1-method-id
- // transformation-2-method-id
- // ...
- // transformation-1-initial-parameters
- // transformation-2-initial-parameters
- // ...
- // stream 1:
- // correction:
- // transformation-1-parameters
- // transformation-2-parameters
- // ...
- // stream 2:
- // correction:
- // transformed-element-1
- // transformed-element-2
- // ...
- // stream 3:
- // correction:
- // base-file
- // element-1
- // element-2
- // ...
-
- static const uint32 kMagic = 'C' | ('o' << 8) | ('u' << 16);
-
- static const uint32 kVersion = 20090320;
-
- // Transformation method IDs.
- enum TransformationMethodId {
- T_COURGETTE_WIN32_X86 = 1, // Windows 32 bit 'Portable Executable' x86.
- };
-};
-
-// For any transform you would implement both a TransformationPatcher and a
-// TransformationPatchGenerator.
-//
-// TransformationPatcher is the interface which abstracts out the actual
-// transformation used on an Element. The patching itself happens outside the
-// actions of a TransformationPatcher. There are four steps.
-//
-// The first step is an Init step. The parameters to the Init step identify the
-// element, for example, range of locations within the original ensemble that
-// correspond to the element.
-//
-// PredictTransformParameters, explained below.
-//
-// The two final steps are 'Transform' - to transform the element into a new
-// representation, and to 'Reform' - to transform from the new representation
-// back to the original form.
-//
-// The Transform step takes some parameters. This allows the transform to be
-// customized to the particular element, or to receive some assistance in the
-// analysis required to perform the transform. The transform parameters might
-// be extensive but mostly predicable, so preceeding Transform is a
-// PredictTransformParameters step.
-//
-class TransformationPatcher {
- public:
- virtual ~TransformationPatcher() {}
-
- // First step: provides parameters for the patching. This would at a minimum
- // identify the element within the ensemble being patched.
- virtual Status Init(SourceStream* parameter_stream) = 0;
-
- // Second step: predicts transform parameters.
- virtual Status PredictTransformParameters(
- SinkStreamSet* predicted_parameters) = 0;
-
- // Third step: transforms element from original representation into alternate
- // representation.
- virtual Status Transform(SourceStreamSet* corrected_parameters,
- SinkStreamSet* transformed_element) = 0;
-
- // Final step: transforms element back from alternate representation into
- // original representation.
- virtual Status Reform(SourceStreamSet* transformed_element,
- SinkStream* reformed_element) = 0;
-};
-
-// TransformationPatchGenerator is the interface which abstracts out the actual
-// transformation used (and adjustment used) when differentially compressing one
-// Element from the |new_ensemble| against a corresponding element in the
-// |old_ensemble|.
-//
-// This is not a pure interface. There is a small amount of inheritance
-// implementation for the fields and actions common to all
-// TransformationPatchGenerators.
-//
-// When TransformationPatchGenerator is subclassed, there will be a
-// corresponding subclass of TransformationPatcher.
-//
-class TransformationPatchGenerator {
- public:
- TransformationPatchGenerator(Element* old_element,
- Element* new_element,
- TransformationPatcher* patcher);
-
- virtual ~TransformationPatchGenerator();
-
- // Returns the TransformationMethodId that identies this transformation.
- virtual CourgettePatchFile::TransformationMethodId Kind() = 0;
-
- // Writes the parameters that will be passed to TransformationPatcher::Init.
- virtual Status WriteInitialParameters(SinkStream* parameter_stream) = 0;
-
- // Predicts the transform parameters for the |old_element|. This must match
- // exactly the output that will be produced by the PredictTransformParameters
- // method of the corresponding subclass of TransformationPatcher. This method
- // is not pure. The default implementation delegates to the patcher to
- // guarantee matching output.
- virtual Status PredictTransformParameters(SinkStreamSet* prediction);
-
- // Writes the desired parameters for the transform of the old element from the
- // file representation to the alternate representation.
- virtual Status CorrectedTransformParameters(SinkStreamSet* parameters) = 0;
-
- // Writes both |old_element| and |new_element| in the new representation.
- // |old_corrected_parameters| will match the |corrected_parameters| passed to
- // the Transform method of the corresponding sublcass of
- // TransformationPatcher.
- //
- // The output written to |old_transformed_element| must match exactly the
- // output written by the Transform method of the corresponding subclass of
- // TransformationPatcher.
- virtual Status Transform(SourceStreamSet* old_corrected_parameters,
- SinkStreamSet* old_transformed_element,
- SinkStreamSet* new_transformed_element) = 0;
-
- // Transforms the new transformed_element back from the alternate
- // representation into the original file format. This must match exactly the
- // output that will be produced by the corresponding subclass of
- // TransformationPatcher::Reform. This method is not pure. The default
- // implementation delegates to the patcher.
- virtual Status Reform(SourceStreamSet* transformed_element,
- SinkStream* reformed_element);
-
- protected:
- Element* old_element_;
- Element* new_element_;
- TransformationPatcher* patcher_;
-};
-
-} // namespace
-#endif // COURGETTE_ENSEMBLE_H_
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