/// <summary>Allocates from unmanaged memory sufficient memory to hold an object of type T.</summary>
/// <typeparam name="T">Native type</typeparam>
/// <param name="value">The value.</param>
/// <returns>SafeCoTaskMemHandle object to an native (unmanaged) memory block the size of T.</returns>
public static SafeCoTaskMemHandle AllocCoTaskMem <T>(T value = default(T)) where T : struct
{
Debug.Assert(typeof(T).StructLayoutAttribute?.Value == LayoutKind.Sequential);
var ret = new SafeCoTaskMemHandle(Marshal.SizeOf(typeof(T)));
Marshal.StructureToPtr(value, ret.handle, false);
return(ret);
}
/// <summary>
/// Allocates from unmanaged memory to represent a structure with a variable length array at the end and marshal these structure elements. It is the
/// callers responsibility to marshal what precedes the trailing array into the unmanaged memory. ONLY structures with attribute StructLayout of
/// LayoutKind.Sequential are supported.
/// </summary>
/// <typeparam name="T">Type of the trailing array of structures</typeparam>
/// <param name="values">Collection of structure objects</param>
/// <param name="count">Number of items in <paramref name="values"/>.</param>
/// <param name="prefixBytes">Number of bytes preceding the trailing array of structures</param>
/// <returns>SafeCoTaskMemHandle object to an native (unmanaged) structure with a trail array of structures</returns>
public static SafeCoTaskMemHandle AllocCoTaskMem <T>(IEnumerable <T> values, int count, int prefixBytes = 0) where T : struct
{
Debug.Assert(typeof(T).StructLayoutAttribute?.Value == LayoutKind.Sequential);
var sz = Marshal.SizeOf(typeof(T));
var result = new SafeCoTaskMemHandle(prefixBytes + sz * count);
var ptr = new IntPtr(result.handle.ToInt64() + prefixBytes);
foreach (var value in values)
{
result.StructureToPtr(value, ptr, false);
ptr = new IntPtr(ptr.ToInt64() + sz);
}
return(result);
}
/// <summary>Allocates unmanaged memory to represent an array of pointers to strings that are then packed in memory behind the array.</summary>
/// <param name="values">The list of strings.</param>
/// <param name="charSet">The character set.</param>
/// <param name="prefixBytes">Number of bytes preceding the trailing array of structures</param>
/// <returns>SafeCoTaskMemHandle object to a native (unmanaged) array of string pointers with trailing strings.</returns>
public static SafeCoTaskMemHandle AllocHGlobal(IEnumerable <string> values, CharSet charSet = CharSet.Auto, int prefixBytes = 0)
{
var coll = values as IList <string> ?? new List <string>(values);
var chSz = charSet == CharSet.Unicode ? 2 : (charSet == CharSet.Auto ? Marshal.SystemDefaultCharSize : 1);
var sz = coll.Sum(s => ((s?.Length + 1) * chSz ?? 0) + IntPtr.Size);
var result = new SafeCoTaskMemHandle(prefixBytes + sz);
var ptr = new IntPtr(result.handle.ToInt64() + prefixBytes);
var enc = chSz == 1 ? System.Text.Encoding.ASCII : System.Text.Encoding.Unicode;
var sptr = new IntPtr(ptr.ToInt64() + IntPtr.Size * coll.Count);
var iptr = ptr;
foreach (var s in coll)
{
var bytes = enc.GetByteCount(s);
Marshal.Copy(enc.GetBytes(s), 0, sptr, bytes);
Marshal.WriteIntPtr(iptr, sptr);
iptr = new IntPtr(iptr.ToInt64() + IntPtr.Size);
sptr = new IntPtr(sptr.ToInt64() + bytes);
}
return(result);
}
public static extern HRESULT PropVariantToUInt64VectorAlloc([In] Ole32.PROPVARIANT propVar, out SafeCoTaskMemHandle pprgf, out uint pcElem);
public static extern HRESULT PropVariantToBuffer([In] Ole32.PROPVARIANT propVar, [In, Out] SafeCoTaskMemHandle pv, uint cb);
/// <summary>Initializes a new instance of the <see cref="SNB"/> class.</summary>
/// <param name="p">The native pointer.</param>
private SNB(IntPtr p)
{
ptr = new SafeCoTaskMemHandle(p, 0, true);
}
/// <summary>Initializes a new instance of the <see cref="SNB"/> class.</summary>
/// <param name="names">The list of names to associate with this instance.</param>
public SNB(IEnumerable <string> names)
{
ptr = names == null ? SafeCoTaskMemHandle.Null : SafeCoTaskMemHandle.CreateFromStringList(names, StringListPackMethod.Packed, CharSet.Unicode);
}
public static extern HRESULT PropVariantToFileTimeVectorAlloc([In] PROPVARIANT propVar, out SafeCoTaskMemHandle pprgf, out uint pcElem);