close #253

src/Shared/HandyControl_Shared/Data/Info/ImageCodecInfo.cs

@@ -0,0 +1,158 @@
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.InteropServices;
+using HandyControl.Tools.Interop;
+
+namespace HandyControl.Data
+{
+    internal sealed class ImageCodecInfo
+    {
+        private string _dllName;
+
+        public Guid Clsid { get; set; }
+
+        public Guid FormatID { get; set; }
+
+        public string CodecName { get; set; }
+
+        public string DllName
+        {
+            [SuppressMessage("Microsoft.Security", "CA2103:ReviewImperativeSecurity")]
+            get
+            {
+                if (_dllName != null)
+                {
+                    new System.Security.Permissions.FileIOPermission(System.Security.Permissions.FileIOPermissionAccess.PathDiscovery, _dllName).Demand();
+                }
+                return _dllName;
+            }
+            [SuppressMessage("Microsoft.Security", "CA2103:ReviewImperativeSecurity")]
+            set
+            {
+                if (value != null)
+                {
+                    new System.Security.Permissions.FileIOPermission(System.Security.Permissions.FileIOPermissionAccess.PathDiscovery, value).Demand();
+                }
+                _dllName = value;
+            }
+        }
+
+        public string FormatDescription { get; set; }
+
+        public string FilenameExtension { get; set; }
+
+        public string MimeType { get; set; }
+
+        public ImageCodecFlags Flags { get; set; }
+
+        public int Version { get; set; }
+
+        public byte[][] SignaturePatterns { get; set; }
+
+        public byte[][] SignatureMasks { get; set; }
+
+        public static ImageCodecInfo[] GetImageDecoders()
+        {
+            ImageCodecInfo[] imageCodecs;
+
+            var status = InteropMethods.Gdip.GdipGetImageDecodersSize(out var numDecoders, out var size);
+
+            if (status != InteropMethods.Gdip.Ok)
+            {
+                throw InteropMethods.Gdip.StatusException(status);
+            }
+
+            var memory = Marshal.AllocHGlobal(size);
+
+            try
+            {
+                status = InteropMethods.Gdip.GdipGetImageDecoders(numDecoders, size, memory);
+
+                if (status != InteropMethods.Gdip.Ok)
+                {
+                    throw InteropMethods.Gdip.StatusException(status);
+                }
+
+                imageCodecs = ConvertFromMemory(memory, numDecoders);
+            }
+            finally
+            {
+                Marshal.FreeHGlobal(memory);
+            }
+
+            return imageCodecs;
+        }
+
+        public static ImageCodecInfo[] GetImageEncoders()
+        {
+            ImageCodecInfo[] imageCodecs;
+
+            var status = InteropMethods.Gdip.GdipGetImageEncodersSize(out var numEncoders, out var size);
+
+            if (status != InteropMethods.Gdip.Ok)
+            {
+                throw InteropMethods.Gdip.StatusException(status);
+            }
+
+            var memory = Marshal.AllocHGlobal(size);
+
+            try
+            {
+                status = InteropMethods.Gdip.GdipGetImageEncoders(numEncoders, size, memory);
+
+                if (status != InteropMethods.Gdip.Ok)
+                {
+                    throw InteropMethods.Gdip.StatusException(status);
+                }
+
+                imageCodecs = ConvertFromMemory(memory, numEncoders);
+            }
+            finally
+            {
+                Marshal.FreeHGlobal(memory);
+            }
+
+            return imageCodecs;
+        }
+
+        public static ImageCodecInfo[] ConvertFromMemory(IntPtr memoryStart, int numCodecs)
+        {
+            var codecs = new ImageCodecInfo[numCodecs];
+
+            int index;
+
+            for (index = 0; index < numCodecs; index++)
+            {
+                var curcodec = (IntPtr)((long)memoryStart + Marshal.SizeOf(typeof(InteropValues.ImageCodecInfoPrivate)) * index);
+                var codecp = new InteropValues.ImageCodecInfoPrivate();
+                InteropMethods.PtrToStructure(curcodec, codecp);
+
+                codecs[index] = new ImageCodecInfo
+                {
+                    Clsid = codecp.Clsid,
+                    FormatID = codecp.FormatID,
+                    CodecName = Marshal.PtrToStringUni(codecp.CodecName),
+                    DllName = Marshal.PtrToStringUni(codecp.DllName),
+                    FormatDescription = Marshal.PtrToStringUni(codecp.FormatDescription),
+                    FilenameExtension = Marshal.PtrToStringUni(codecp.FilenameExtension),
+                    MimeType = Marshal.PtrToStringUni(codecp.MimeType),
+                    Flags = (ImageCodecFlags) codecp.Flags,
+                    Version = codecp.Version,
+                    SignaturePatterns = new byte[codecp.SigCount][],
+                    SignatureMasks = new byte[codecp.SigCount][]
+                };
+
+                for (var j = 0; j < codecp.SigCount; j++)
+                {
+                    codecs[index].SignaturePatterns[j] = new byte[codecp.SigSize];
+                    codecs[index].SignatureMasks[j] = new byte[codecp.SigSize];
+
+                    Marshal.Copy((IntPtr)((long)codecp.SigMask + j * codecp.SigSize), codecs[index].SignatureMasks[j], 0, codecp.SigSize);
+                    Marshal.Copy((IntPtr)((long)codecp.SigPattern + j * codecp.SigSize), codecs[index].SignaturePatterns[j], 0, codecp.SigSize);
+                }
+            }
+
+            return codecs;
+        }
+    }
+}