DynaMD

About

Helper objects to browse complex structures returned by ClrMD. This is useful to quickly write scripts to analyze memory dumps.

The library leverages the dynamic keyword to give direct access to memory structures.

How to use

Given an address and a ClrMD ClrHeap instance, you can get a dynamic proxy by calling GetProxy:

var proxy = heap.GetProxy(0x00001000);

Or all the instances of a given type:

// Using generics:
var proxies1 = heap.GetProxies<string>();

// Or writing the type name (useful if you don't reference it):
var proxies2 = heap.GetProxies("System.String");

From there, you can access any field like you would with a "real" object:

Console.WriteLine(proxy.Value);
Console.WriteLine((string)proxy.Child.Name);
Console.WriteLine(proxy.Description.Size.Width * proxy.Description.Size.Height);

Only fields are supported, but automatic properties are translated:

class SomeType
{
    private int _backingField;
    public int Field1 => _backingField;
    public int Field2 { get; }
}

var proxy = heap.GetProxies<SomeType>().First();

var value1 = proxy._backingField; // Calling proxy.Field1 is not supported
var value2 = proxy.Field2; // Automatically translated to <Field2>k__BackingField

Primitive types are automatically converted:

class SomeType
{
    public int IntValue;
    public double DoubleValue;
}

var proxy = heap.GetProxies<SomeType>().First();

Console.WriteLine(proxy.IntValue.GetType()); // System.Int32
Console.WriteLine(proxy.DoubleValue.GetType()); // System.Double

Non-primitive proxies can be cast to string or blittable structs:

struct BlittableStruct
{
    public int Value;
}

class SomeType
{
    public BlittableStruct StructValue;
    public DateTime DateTimeValue;
    public string StringValue;
}

var proxy = heap.GetProxies<SomeType>().First();

BlittableStruct structValue = (BlittableStruct)proxy.StructValue;
DateTime dateTimeValue = (DateTime)proxy.DateTimeValue;
string stringValue = (string)proxy.stringValue;

You can also enumerate the contents of arrays, get the length, or use an indexer:

class SomeType
{
    public int[] ArrayValue;
}

var proxy = heap.GetProxies<SomeType>().First();

Console.WriteLine("Length: " + proxy.ArrayValue.Length);
Console.WriteLine("First element: " + proxy.ArrayValue[0]);

foreach (var value in proxy.ArrayValue)
{
    Console.WriteLine(value);
}

To retrieve the address of a proxified object, explicitely cast it to ulong. Also, calling .ToString() on a proxy will return the address encoded in hexadecimal:

var proxy = heap.GetProxy(0x1000);
var address = (ulong)proxy;
Console.WriteLine("{0:x2}", address); // 0x1000
Console.WriteLine(proxy); // 0x1000

To retrieve the instance of ClrType, call GetClrType():

ClrType type = proxy.GetClrType();

Check the unit tests for more examples.