Package ghidra.app.util.bin.format.golang.structmapping

Class StructureContext<T>

java.lang.Object
ghidra.app.util.bin.format.golang.structmapping.StructureContext<T>
Type Parameters:
T - a java class that has been tagged with a StructureMapping annotation.
public class StructureContext<T> extends Object
Information about an instance of a structure that has been read from the memory of a Ghidra program.

All StructureMapping tagged classes must have a ContextField tagged StructureContext field for that class to be able to access meta-data about its self, and for other classes to reference it when performing markup: 

 @StructureMapping(structureName = "mydatatype")
 class MyDataType {
        @ContextField
        private StructureContext<MyDataType> context;
 
        @FieldMapping
        private long someField;
  ...

  • Field Details

    • dataTypeMapper

      protected final DataTypeMapper dataTypeMapper

    • mappingInfo

      protected final StructureMappingInfo<T> mappingInfo

    • containingFieldDataType

      protected final DataType containingFieldDataType

    • reader

      protected final BinaryReader reader

    • structureStart

      protected final long structureStart

    • structureInstance

      protected T structureInstance

    • structureDataType

      protected Structure structureDataType

  • Constructor Details

    • StructureContext

      public StructureContext(DataTypeMapper dataTypeMapper, StructureMappingInfo<T> mappingInfo, BinaryReader reader)
      Creates an instance of a StructureContext.
      Parameters:
      dataTypeMapper - mapping context for the program
      mappingInfo - mapping information about this structure
      reader - BinaryReader positioned at the start of the structure to be read, or null if this is a limited-use context object

    • StructureContext

      public StructureContext(DataTypeMapper dataTypeMapper, StructureMappingInfo<T> mappingInfo, DataType containingFieldDataType, BinaryReader reader)
      Creates an instance of a StructureContext.
      Parameters:
      dataTypeMapper - mapping context for the program
      mappingInfo - mapping information about this structure
      containingFieldDataType - optional, the DataType of the field that contained the instance being deserialized
      reader - BinaryReader positioned at the start of the structure to be read, or null if this is a limited-use context object

  • Method Details

    • readNewInstance

      public T readNewInstance() throws IOException
      Creates a new instance of the structure by deserializing the structure's marked fields into java fields.
      Returns:
      new instance of structure
      Throws:
      IOException - if error reading

    • getMappingInfo

      public StructureMappingInfo<T> getMappingInfo()
      Returns the StructureMappingInfo for this structure's class.
      Returns:
      StructureMappingInfo for this structure's class

    • getDataTypeMapper

      public DataTypeMapper getDataTypeMapper()
      Returns a reference to the root DataTypeMapper, as a plain DataTypeMapper type. If a more specific DataTypeMapper type is needed, either type-cast this value, or use a ContextField tag on a field in your class that specifies the correct DataTypeMapper type.
      Returns:
      the program mapping context that control's this structure instance

    • getContainingFieldDataType

      public DataType getContainingFieldDataType()
      Returns the DataType of the field that this object instance was contained inside of, or null if this instance was not a field inside another structure.

      For instance, if a structure was being deserialized because it was a field inside another structure, the actual Ghidra data type of the field may be slightly different than the structure data type defined at the top of the structmapped class (ie. @StructureMapping(structureName='struct'). The containing field's data type could allow custom logic to enrich or modify this struct's behavior.

      Returns:
      DataType of the field that this object instance was contained inside of

    • getStructureAddress

      public Address getStructureAddress()
      Returns the address in the program of this structure instance.
      Returns:
      Address

    • getFieldAddress

      public Address getFieldAddress(long fieldOffset)
      Returns the address of an offset from the start of this structure instance.
      Parameters:
      fieldOffset - number of bytes from the beginning of this structure where a field (or other location of interest) starts
      Returns:
      Address of specified offset

    • getFieldLocation

      public long getFieldLocation(long fieldOffset)
      Returns the stream location of an offset from the start of this structure instance.
      Parameters:
      fieldOffset - number of bytes from the beginning of this structure where a field (or other location of interest) starts
      Returns:
      absolute offset / position in the program / BinaryReader stream

    • getStructureStart

      public long getStructureStart()
      Returns the stream location of this structure instance.
      Returns:
      absolute offset / position in the program / BinaryReader stream of this structure

    • getStructureEnd

      public long getStructureEnd()
      Returns the stream location of the end of this structure instance.
      Returns:
      absolute offset / position in the program / BinaryReader stream of the byte after this structure

    • getStructureLength

      public int getStructureLength()
      Returns the length of this structure instance.
      Returns:
      length of this structure, or 0 if this structure is a variable length structure that does not have a fixed length

    • getStructureInstance

      public T getStructureInstance()
      Returns a reference to the object instance that was deserialized.
      Returns:
      reference to deserialized structure mapped object

    • getReader

      public BinaryReader getReader()
      Returns the BinaryReader that is used to deserialize this structure.
      Returns:
      BinaryReader that is used to deserialize this structure

    • getFieldReader

      public BinaryReader getFieldReader(long fieldOffset)
      Returns an independent BinaryReader that is positioned at the start of the specified field.
      Parameters:
      fieldOffset - number of bytes from the beginning of this structure where a field (or other location of interest) starts
      Returns:
      new BinaryReader positioned at the specified relative offset

    • createFieldContext

      public FieldContext<T> createFieldContext(FieldMappingInfo<T> fmi, boolean includeReader)
      Creates a new FieldContext for a specific field.
      Parameters:
      fmi - field of interest
      includeReader - boolean flag, if true create a BinaryReader for the field, if false no BinaryReader will be created
      Returns:
      new FieldContext

    • getStructureDataType

      public Structure getStructureDataType() throws IOException
      Returns the Ghidra structure data type that represents this object.

      If this is an instance of a variable length structure mapped class, a custom structure data type will be minted that exactly matches this instance's variable length fields.

      Returns:
      Ghidra structure data type that represents this object
      Throws:
      IOException - if error constructing new struct data type

    • toString

      public String toString()
      Overrides:
      toString in class Object