/// <summary>
/// Generates a hook that is called before any native code
/// </summary>
/// <param name="method">Method to generate the hook in</param>
/// <param name="options">Configurable hook options</param>
/// <returns>A <see cref="MergableMethod"/> instance</returns>
public static MergableMethod GenerateBeginHook
(
this MethodDefinition method,
HookOptions options = HookOptions.Default,
VariableDefinition result_variable = null
)
{
// emit call at offset 0
// add or get the types where we are storing out auto generated hooks & their delegates
var hooks_type = method.DeclaringType.GetHooksType();
var hooks_delegates_type = method.DeclaringType.GetHooksDelegateType();
// generate the hook handler delegate
var hook_delegate_emitter = new HookDelegateEmitter("OnPre", method, options);
var hook_handler = hook_delegate_emitter.Emit();
hooks_delegates_type.NestedTypes.Add(hook_handler);
// generate the api hook external modules can attach to
var hook_field = new FieldDefinition("Pre" + method.GetSafeName(), FieldAttributes.Public | FieldAttributes.Static, hook_handler);
hooks_type.Fields.Add(hook_field);
// generate the call to the delegate
var hook_emitter = new HookEmitter(hook_field, method,
(options & HookOptions.Cancellable) != 0,
(options & HookOptions.ReferenceParameters) != 0,
result_variable
);
var result = hook_emitter.Emit();
//instructions.MergeInto(method, 0);
// end of method
var invoke_method = hook_handler.Resolve().Method("Invoke");
if (invoke_method.ReturnType.FullName != "System.Void")
{
result.Instructions = result.Instructions.Concat(new[]
{
Instruction.Create(OpCodes.Brtrue_S, method.Body.Instructions.First()),
Instruction.Create(OpCodes.Br_S, method.Body.Instructions.Last())
});
}
return(result);
}
/// <summary>
/// Generates a hook that is called after native code
/// </summary>
/// <param name="method">Method to generate the hook in</param>
/// <param name="options">Configurable hook options</param>
/// <returns>A <see cref="MergableMethod"/> instance</returns>
public static MergableMethod GenerateHook
(
this IEnumerable <ParameterDefinition> parameters,
string name,
TypeDefinition parentType,
TypeDefinition returnType, HookOptions flags, ModuleDefinition module,
HookOptions options = HookOptions.Post,
VariableDefinition result_variable = null
)
{
// emit call at each ret instruction
// add or get the types where we are storing out auto generated hooks & their delegates
var hooks_type = parentType.GetHooksType();
var hooks_delegates_type = parentType.GetHooksDelegateType();
// generate the hook handler delegate
var hook_delegate_emitter = new HookDelegateEmitter("On" + name, parameters, returnType, options, module);
var hook_handler = hook_delegate_emitter.Emit();
hooks_delegates_type.NestedTypes.Add(hook_handler);
// generate the api hook external modules can attach to
var hook_field = new FieldDefinition(name, FieldAttributes.Public | FieldAttributes.Static, hook_handler);
hooks_type.Fields.Add(hook_field);
// generate the call to the delegate
var hook_emitter = new HookEmitter(hook_field, parameters, false, false, result_variable);
var result = hook_emitter.Emit();
// end of method
return(result);
}
/// <summary>
/// Generates a hook that is called after native code
/// </summary>
/// <param name="method">Method to generate the hook in</param>
/// <param name="options">Configurable hook options</param>
/// <returns>A <see cref="MergableMethod"/> instance</returns>
public static MergableMethod GenerateEndHook
(
this MethodDefinition method,
HookOptions options = HookOptions.Default,
VariableDefinition result_variable = null
)
{
// emit call at each ret instruction
// add or get the types where we are storing out auto generated hooks & their delegates
var hooks_type = method.DeclaringType.GetHooksType();
var hooks_delegates_type = method.DeclaringType.GetHooksDelegateType();
// generate the hook handler delegate
var hook_delegate_emitter = new HookDelegateEmitter("OnPost", method, options & ~(
HookOptions.ReferenceParameters |
HookOptions.Cancellable
));
var hook_handler = hook_delegate_emitter.Emit();
hooks_delegates_type.NestedTypes.Add(hook_handler);
// generate the api hook external modules can attach to
var hook_field = new FieldDefinition("Post" + method.GetSafeName(), FieldAttributes.Public | FieldAttributes.Static, hook_handler);
hooks_type.Fields.Add(hook_field);
// generate the call to the delegate
var hook_emitter = new HookEmitter(hook_field, method, false, false, result_variable);
var result = hook_emitter.Emit();
// end of method
return(result);
}
