示例#1
0
        static SafeHGlobalHandle AllocHGlobal(int cb)
        {
            if (cb < 0)
            {
                throw new ArgumentOutOfRangeException(nameof(cb), "The value of this argument must be non-negative");
            }

            var result = new SafeHGlobalHandle();

            //
            // CER
            //
            RuntimeHelpers.PrepareConstrainedRegions();

            result._pointer = Marshal.AllocHGlobal(cb);
            return(result);
        }
示例#2
0
        /// <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 preceeds
        /// the trailinh 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="prefixBytes">Number of bytes preceeding the trailing array of structures</param>
        /// <param name="values">Collection of structure objects</param>
        /// <param name="count"></param>
        /// <returns>SafeHGlobalHandle object to an native (unmanaged) structure
        /// with a trail array of structures</returns>
        public static SafeHGlobalHandle AllocHGlobal <T>(int prefixBytes, IEnumerable <T> values, int count) where T
        : struct
        {
            var structLayoutAttribute = typeof(T).StructLayoutAttribute;

            Debug.Assert(structLayoutAttribute != null && structLayoutAttribute.Value == LayoutKind.Sequential);

            SafeHGlobalHandle result = AllocHGlobal(prefixBytes + Marshal.SizeOf(typeof(T)) * count);

            IntPtr ptr = result._pointer + prefixBytes;

            foreach (var value in values)
            {
                Marshal.StructureToPtr(value, ptr, false);
                ptr += Marshal.SizeOf(typeof(T));
            }

            return(result);
        }