2015-03-13 10:31:52 +01:00

646 lines
21 KiB
C#

/*
* Greenshot - a free and open source screenshot tool
* Copyright (C) 2007-2015 Thomas Braun, Jens Klingen, Robin Krom
*
* For more information see: http://getgreenshot.org/
* The Greenshot project is hosted on Sourceforge: http://sourceforge.net/projects/greenshot/
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using System;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Messaging;
using System.Runtime.Remoting.Proxies;
namespace Greenshot.Interop {
/// <summary>
/// Wraps a late-bound COM server.
/// </summary>
public sealed class COMWrapper : RealProxy, IDisposable, IRemotingTypeInfo {
private const int MK_E_UNAVAILABLE = -2147221021;
private const int CO_E_CLASSSTRING = -2147221005;
#region Private Data
/// <summary>
/// Holds reference to the actual COM object which is wrapped by this proxy
/// </summary>
private object _COMObject;
/// <summary>
/// Type of the COM object, set on constructor after getting the COM reference
/// </summary>
private Type _COMType;
/// <summary>
/// The type of which method calls are intercepted and executed on the COM object.
/// </summary>
private Type _InterceptType;
#endregion
[DllImport("ole32.dll")]
static extern int ProgIDFromCLSID([In] ref Guid clsid, [MarshalAs(UnmanagedType.LPWStr)] out string lplpszProgID);
#region Construction
/// <summary>
/// Gets a COM object and returns the transparent proxy which intercepts all calls to the object
/// </summary>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The <paramref name="type"/> must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetInstance<T>() {
Type type = typeof(T);
if (null == type) {
throw new ArgumentNullException("type");
}
if (!type.IsInterface) {
throw new ArgumentException("The specified type must be an interface.", "type");
}
ComProgIdAttribute progIDAttribute = ComProgIdAttribute.GetAttribute(type);
if (null == progIDAttribute || null == progIDAttribute.Value || 0 == progIDAttribute.Value.Length) {
throw new ArgumentException("The specified type must define a ComProgId attribute.", "type");
}
string progId = progIDAttribute.Value;
// Convert from clsid to Prog ID, if needed
if (progId.StartsWith("clsid:")) {
Guid guid = new Guid(progId.Substring(6));
int result = ProgIDFromCLSID(ref guid, out progId);
if (result != 0) {
//LOG.WarnFormat("Error {0} getting progId {1}", result, progIDAttribute.Value);
} else {
//LOG.InfoFormat("Mapped {0} to progId {1}", progIDAttribute.Value, progId);
}
}
object comObject = null;
try {
comObject = Marshal.GetActiveObject(progId);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE) {
//LOG.DebugFormat("No current instance of {0} object available.", progId);
} else if (comE.ErrorCode == CO_E_CLASSSTRING) {
//LOG.WarnFormat("Unknown progId {0}", progId);
} else {
//LOG.Warn("Error getting active object for " + progId, comE);
}
} catch (Exception) {
//LOG.Warn("Error getting active object for " + progId, e);
}
if (comObject != null) {
COMWrapper wrapper = new COMWrapper(comObject, type);
return (T)wrapper.GetTransparentProxy();
}
return default(T);
}
/// <summary>
/// Gets or creates a COM object and returns the transparent proxy which intercepts all calls to the object
/// The ComProgId can be a normal ComProgId or a GUID prefixed with "clsid:"
/// </summary>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
/// <remarks>The <paramref name="type"/> must be an interface decorated with the <see cref="ComProgIdAttribute"/>attribute.</remarks>
public static T GetOrCreateInstance<T>() {
Type type = typeof(T);
if (null == type) {
throw new ArgumentNullException("type");
}
if (!type.IsInterface) {
throw new ArgumentException("The specified type must be an interface.", "type");
}
ComProgIdAttribute progIDAttribute = ComProgIdAttribute.GetAttribute(type);
if (null == progIDAttribute || null == progIDAttribute.Value || 0 == progIDAttribute.Value.Length) {
throw new ArgumentException("The specified type must define a ComProgId attribute.", "type");
}
object comObject = null;
Type comType = null;
string progId = progIDAttribute.Value;
// Convert from clsid to Prog ID, if needed
if (progId.StartsWith("clsid:")) {
Guid guid = new Guid(progId.Substring(6));
int result = ProgIDFromCLSID(ref guid, out progId);
if (result != 0) {
//LOG.WarnFormat("Error {0} getting progId {1}", result, progIDAttribute.Value);
} else {
//LOG.InfoFormat("Mapped {0} to progId {1}", progIDAttribute.Value, progId);
}
}
try {
comObject = Marshal.GetActiveObject(progId);
} catch (COMException comE) {
if (comE.ErrorCode == MK_E_UNAVAILABLE) {
//LOG.DebugFormat("No current instance of {0} object available.", progId);
} else if (comE.ErrorCode == CO_E_CLASSSTRING) {
//LOG.WarnFormat("Unknown progId {0} (application not installed)", progId);
return default(T);
} else {
//LOG.Warn("Error getting active object for " + progId, comE);
}
} catch (Exception) {
//LOG.Warn("Error getting active object for " + progId, e);
}
// Did we get the current instance? If not, try to create a new
if (comObject == null) {
try {
comType = Type.GetTypeFromProgID(progId, true);
} catch (Exception) {
//LOG.Warn("Error type for " + progId, ex);
}
if (comType != null) {
try {
comObject = Activator.CreateInstance(comType);
if (comObject != null) {
//LOG.DebugFormat("Created new instance of {0} object.", progId);
}
} catch (Exception) {
//LOG.Warn("Error creating object for " + progId, e);
}
}
}
if (comObject != null) {
COMWrapper wrapper = new COMWrapper(comObject, type);
return (T)wrapper.GetTransparentProxy();
}
return default(T);
}
/// <summary>
/// Wrap an object and return the transparent proxy which intercepts all calls to the object
/// </summary>
/// <param name="comObject">An object to intercept</param>
/// <param name="type">Interface which defines the method and properties to intercept</param>
/// <returns>Transparent proxy to the real proxy for the object</returns>
private static object Wrap(object comObject, Type type) {
if (null == comObject) {
throw new ArgumentNullException("comObject");
}
if (null == type) {
throw new ArgumentNullException("type");
}
COMWrapper wrapper = new COMWrapper(comObject, type);
return wrapper.GetTransparentProxy();
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="comObject">
/// The COM object to wrap.
/// </param>
/// <param name="type">
/// The interface type to impersonate.
/// </param>
private COMWrapper(object comObject, Type type)
: base(type) {
this._COMObject = comObject;
this._COMType = comObject.GetType();
this._InterceptType = type;
}
#endregion
#region Clean up
/// <summary>
/// If <see cref="Dispose"/> is not called, we need to make
/// sure that the COM object is still cleaned up.
/// </summary>
~COMWrapper() {
this.Dispose(false);
}
/// <summary>
/// Cleans up the COM object.
/// </summary>
public void Dispose() {
this.Dispose(true);
GC.SuppressFinalize(this);
}
/// <summary>
/// Release the COM reference
/// </summary>
/// <param name="disposing">
/// <see langword="true"/> if this was called from the
/// <see cref="IDisposable"/> interface.
/// </param>
private void Dispose(bool disposing) {
if (disposing && null != this._COMObject) {
if (Marshal.IsComObject(this._COMObject)) {
try {
while (Marshal.ReleaseComObject(this._COMObject) > 0);
} catch (Exception) {
//LOG.WarnFormat("Problem releasing {0}", _COMType);
//LOG.Warn("Error: ", ex);
}
}
this._COMObject = null;
}
}
#endregion
#region Object methods
/// <summary>
/// Returns a string representing the wrapped object.
/// </summary>
/// <returns>
/// The full name of the intercepted type.
/// </returns>
public override string ToString() {
return this._InterceptType.FullName;
}
/// <summary>
/// Returns the hash code of the wrapped object.
/// </summary>
/// <returns>
/// The hash code of the wrapped object.
/// </returns>
public override int GetHashCode() {
return this._COMObject.GetHashCode();
}
/// <summary>
/// Compares this object to another.
/// </summary>
/// <param name="value">
/// The value to compare to.
/// </param>
/// <returns>
/// <see langword="true"/> if the objects are equal.
/// </returns>
public override bool Equals(object value) {
if (null != value && RemotingServices.IsTransparentProxy(value)) {
COMWrapper wrapper = RemotingServices.GetRealProxy(value) as COMWrapper;
if (null != wrapper) {
return this._COMObject == wrapper._COMObject;
}
}
return base.Equals(value);
}
/// <summary>
/// Returns the base type for a reference type.
/// </summary>
/// <param name="byRefType">
/// The reference type.
/// </param>
/// <returns>
/// The base value type.
/// </returns>
/// <exception cref="ArgumentNullException">
/// <paramref name="byRefType"/> is <see langword="null"/>.
/// </exception>
private static Type GetByValType(Type byRefType) {
if (null == byRefType) {
throw new ArgumentNullException("byRefType");
}
if (byRefType.IsByRef) {
string name = byRefType.FullName;
name = name.Substring(0, name.Length - 1);
byRefType = byRefType.Assembly.GetType(name, true);
}
return byRefType;
}
#endregion
/// <summary>
/// Use this static method to cast a wrapped proxy to a new wrapper proxy of the supplied type.
/// In English, use this to cast you base "COM" interface to a specialized interface.
/// E.G. Outlook Item -> MailItem
/// </summary>
/// <typeparam name="T">the type you want to cast to</typeparam>
/// <param name="wrapperProxy">The wrapper interface, e.g. something you got back from calling GetItem</param>
/// <returns>A new wrapper proxy for the specified type</returns>
public static T Cast<T>(object wrapperProxy) {
if (wrapperProxy == null) {
return default(T);
}
Type newType = typeof(T);
COMWrapper oldWrapper = RemotingServices.GetRealProxy(wrapperProxy) as COMWrapper;
if (oldWrapper == null) {
throw new ArgumentException("wrapper proxy was no COMWrapper");
}
if (oldWrapper._InterceptType.IsAssignableFrom(newType)) {
COMWrapper newWrapper = new COMWrapper(oldWrapper._COMObject, newType);
return (T)newWrapper.GetTransparentProxy();
}
throw new InvalidCastException(string.Format("{0} is not assignable from {1}", oldWrapper._InterceptType, newType));
}
/// <summary>
/// Returns the "com" type of the wrapperproxy, making it possible to perform reflection on it.
/// </summary>
/// <param name="wrapperProxy">wrapperProxy to get the type from</param>
/// <returns>Type</returns>
public static Type GetUnderlyingTypeForWrapper(object wrapperProxy) {
Type returnType = null;
COMWrapper wrapper = RemotingServices.GetRealProxy(wrapperProxy) as COMWrapper;
if (wrapper != null) {
IDispatch dispatch = wrapper._COMObject as IDispatch;
if (dispatch != null) {
int result = dispatch.GetTypeInfo(0, 0, out returnType);
if (result != 0) {
//LOG.DebugFormat("GetTypeInfo : 0x{0} ({1})", result.ToString("X"), result);
}
}
}
return returnType;
}
/// <summary>
/// Return the Type of a IDispatch
/// </summary>
/// <param name="dispatch">IDispatch to get the type object for</param>
/// <returns>Type of the IDispatch</returns>
public static Type GetUnderlyingType(IDispatch dispatch) {
Type returnType = null;
if (dispatch != null) {
int result = dispatch.GetTypeInfo(0, 0, out returnType);
if (result != 0) {
//LOG.DebugFormat("GetTypeInfo : 0x{0} ({1})", result.ToString("X"), result);
}
}
return returnType;
}
/// <summary>
/// Dump the Type-Information for the Type to the log, this uses reflection
/// </summary>
/// <param name="type">Type to inspect</param>
public static void DumpTypeInfo(Type type) {
//LOG.InfoFormat("Type information for Type with name: {0}", type.Name);
try {
foreach (MemberInfo memberInfo in type.GetMembers()) {
//LOG.InfoFormat("Member: {0};", memberInfo.ToString());
}
} catch (Exception) {
//LOG.Error(memberException);
}
try {
foreach (PropertyInfo propertyInfo in type.GetProperties()) {
//LOG.InfoFormat("Property: {0};", propertyInfo.ToString());
}
} catch (Exception) {
//LOG.Error(propertyException);
}
try {
foreach (FieldInfo fieldInfo in type.GetFields()) {
//LOG.InfoFormat("Field: {0};", fieldInfo.ToString());
}
} catch (Exception) {
//LOG.Error(fieldException);
}
//LOG.InfoFormat("Type information end.");
}
/// <summary>
/// Intercept method calls
/// </summary>
/// <param name="myMessage">
/// Contains information about the method being called
/// </param>
/// <returns>
/// A <see cref="ReturnMessage"/>.
/// </returns>
public override IMessage Invoke(IMessage myMessage) {
IMethodCallMessage callMessage = myMessage as IMethodCallMessage;
if (null == callMessage) {
//LOG.DebugFormat("Message type not implemented: {0}", myMessage.GetType().ToString());
return null;
}
MethodInfo method = callMessage.MethodBase as MethodInfo;
if (null == method) {
//LOG.DebugFormat("Unrecognized Invoke call: {0}", callMessage.MethodBase.ToString());
return null;
}
object returnValue = null;
object[] outArgs = null;
int outArgsCount = 0;
string methodName = method.Name;
Type returnType = method.ReturnType;
BindingFlags flags = BindingFlags.InvokeMethod;
int argCount = callMessage.ArgCount;
object invokeObject;
Type invokeType;
Type byValType;
object[] args;
object arg;
COMWrapper[] originalArgs;
COMWrapper wrapper;
ParameterModifier[] argModifiers = null;
ParameterInfo[] parameters = null;
ParameterInfo parameter;
if ("Dispose" == methodName && 0 == argCount && typeof(void) == returnType) {
this.Dispose();
} else if ("ToString" == methodName && 0 == argCount && typeof(string) == returnType) {
returnValue = this.ToString();
} else if ("GetType" == methodName && 0 == argCount && typeof(System.Type) == returnType) {
returnValue = this._InterceptType;
} else if ("GetHashCode" == methodName && 0 == argCount && typeof(int) == returnType) {
returnValue = this.GetHashCode();
} else if ("Equals" == methodName && 1 == argCount && typeof(bool) == returnType) {
returnValue = this.Equals(callMessage.Args[0]);
} else if (1 == argCount && typeof(void) == returnType && (methodName.StartsWith("add_") || methodName.StartsWith("remove_"))) {
bool removeHandler = methodName.StartsWith("remove_");
methodName = methodName.Substring(removeHandler ? 7 : 4);
Delegate handler = callMessage.InArgs[0] as Delegate;
if (null == handler) {
return new ReturnMessage(new ArgumentNullException("handler"), callMessage);
}
} else {
invokeObject = this._COMObject;
invokeType = this._COMType;
if (methodName.StartsWith("get_")) {
// Property Get
methodName = methodName.Substring(4);
flags = BindingFlags.GetProperty;
args = callMessage.InArgs;
} else if (methodName.StartsWith("set_")) {
// Property Set
methodName = methodName.Substring(4);
flags = BindingFlags.SetProperty;
args = callMessage.InArgs;
} else {
args = callMessage.Args;
if (null != args && 0 != args.Length) {
// Modifiers for ref / out parameters
argModifiers = new ParameterModifier[1];
argModifiers[0] = new ParameterModifier(args.Length);
parameters = method.GetParameters();
for (int i = 0; i < parameters.Length; i++) {
parameter = parameters[i];
if (parameter.IsOut || parameter.ParameterType.IsByRef) {
argModifiers[0][i] = true;
outArgsCount++;
}
}
if (0 == outArgsCount) {
argModifiers = null;
}
}
}
// Un-wrap wrapped COM objects before passing to the method
if (null == args || 0 == args.Length) {
originalArgs = null;
} else {
originalArgs = new COMWrapper[args.Length];
for (int i = 0; i < args.Length; i++) {
if (null != args[i] && RemotingServices.IsTransparentProxy(args[i])) {
wrapper = RemotingServices.GetRealProxy(args[i]) as COMWrapper;
if (null != wrapper) {
originalArgs[i] = wrapper;
args[i] = wrapper._COMObject;
}
} else if (0 != outArgsCount && argModifiers[0][i]) {
byValType = GetByValType(parameters[i].ParameterType);
if (byValType.IsInterface) {
// If we're passing a COM object by reference, and
// the parameter is null, we need to pass a
// DispatchWrapper to avoid a type mismatch exception.
if (null == args[i]) {
args[i] = new DispatchWrapper(null);
}
} else if (typeof(Decimal) == byValType) {
// If we're passing a decimal value by reference,
// we need to pass a CurrencyWrapper to avoid a
// type mismatch exception.
// http://support.microsoft.com/?kbid=837378
args[i] = new CurrencyWrapper(args[i]);
}
}
}
}
try {
returnValue = invokeType.InvokeMember(methodName, flags, null, invokeObject, args, argModifiers, null, null);
} catch (Exception ex) {
return new ReturnMessage(ex, callMessage);
}
// Handle enum and interface return types
if (null != returnValue) {
if (returnType.IsInterface) {
// Wrap the returned value in an intercepting COM wrapper
if (Marshal.IsComObject(returnValue)) {
returnValue = COMWrapper.Wrap(returnValue, returnType);
}
} else if (returnType.IsEnum) {
// Convert to proper Enum type
returnValue = Enum.Parse(returnType, returnValue.ToString());
}
}
// Handle out args
if (0 != outArgsCount) {
outArgs = new object[args.Length];
for (int i = 0; i < parameters.Length; i++) {
if (!argModifiers[0][i]) {
continue;
}
arg = args[i];
if (null == arg) {
continue;
}
parameter = parameters[i];
wrapper = null;
byValType = GetByValType(parameter.ParameterType);
if (typeof(Decimal) == byValType) {
if (arg is CurrencyWrapper) {
arg = ((CurrencyWrapper)arg).WrappedObject;
}
} else if (byValType.IsEnum) {
arg = Enum.Parse(byValType, arg.ToString());
} else if (byValType.IsInterface) {
if (Marshal.IsComObject(arg)) {
wrapper = originalArgs[i];
if (null != wrapper && wrapper._COMObject != arg) {
wrapper.Dispose();
wrapper = null;
}
if (null == wrapper) {
wrapper = new COMWrapper(arg, byValType);
}
arg = wrapper.GetTransparentProxy();
}
}
outArgs[i] = arg;
}
}
}
return new ReturnMessage(returnValue, outArgs, outArgsCount, callMessage.LogicalCallContext, callMessage);
}
/// <summary>
/// Implementation for the interface IRemotingTypeInfo
/// This makes it possible to cast the COMWrapper
/// </summary>
/// <param name="toType">Type to cast to</param>
/// <param name="o">object to cast</param>
/// <returns></returns>
public bool CanCastTo(Type toType, object o) {
bool returnValue = _InterceptType.IsAssignableFrom(toType);
return returnValue;
}
/// <summary>
/// Implementation for the interface IRemotingTypeInfo
/// </summary>
public string TypeName {
get {
throw new NotSupportedException();
}
set {
throw new NotSupportedException();
}
}
}
}