Merge pull request #957 from shimat/UnmanagedType_LPStr

enable UnmanagedType.LPUTF8Str for non-Windows platforms

appveyor.yml

@@ -51,6 +51,7 @@ init:
     Write-Host "PLATFORM = "$env:PLATFORM
     Write-Host "CONFIGURATION = "$env:CONFIGURATION
     Write-Host "APPVEYOR_SAVE_CACHE_ON_ERROR = "$env:APPVEYOR_SAVE_CACHE_ON_ERROR
+#- ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))
 
 #on_finish:
 #  - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))

src/OpenCvSharp/Modules/core/FileNodeIterator.cs

@@ -10,7 +10,7 @@ namespace OpenCvSharp
     /// <summary>
     /// File Storage Node class
     /// </summary>
-    public class FileNodeIterator : DisposableCvObject, IEquatable<FileNodeIterator>, IEnumerator<FileNode>
+    public class FileNodeIterator : DisposableCvObject, IEquatable<FileNodeIterator?>, IEnumerator<FileNode>
     {
         /// <summary>
         /// The default constructor
@@ -141,7 +141,7 @@ public FileNodeIterator ReadRaw(string fmt, byte[] vec, long maxCount = int.MaxV
         /// </summary>
         /// <param name="it"></param>
         /// <returns></returns>
-        public bool Equals(FileNodeIterator it)
+        public bool Equals(FileNodeIterator? it)
         {
             if (it is null)
                 return false;

src/OpenCvSharp/Modules/core/RNG.cs

@@ -328,7 +328,7 @@ public double Gaussian(double sigma)
         }
 
         /// <inheritdoc />
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             if (obj is RNG rng)
                 return Equals(rng);

src/OpenCvSharp/Modules/core/Struct/Point3i.cs

@@ -222,7 +222,7 @@ public readonly bool Equals(Point3i other)
         }
 
         /// <inheritdoc />
-        public override readonly bool Equals(object obj)
+        public override readonly bool Equals(object? obj)
         {
             return obj is Point3i other && Equals(other);
         }

src/OpenCvSharp/Modules/core/Struct/Size2d.cs

@@ -97,7 +97,7 @@ public readonly bool Equals(Size2d other)
         }
 
         /// <inheritdoc />
-        public override readonly bool Equals(object obj)
+        public override readonly bool Equals(object? obj)
         {
             return obj is Size2d other && Equals(other);
         }

src/OpenCvSharp/Modules/videoio/FourCC.cs

@@ -157,7 +157,7 @@ public static FourCC FromInt32(int code)
         }
 
         /// <inheritdoc />
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             if (obj is FourCC enumValue)
                 return Equals(enumValue);

src/OpenCvSharp/OpenCvSharp.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;netstandard2.1;netcoreapp2.1;net48;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;netstandard2.1;netcoreapp2.1;netcoreapp3.1;net48;net461</TargetFrameworks>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <AssemblyName>OpenCvSharp</AssemblyName>

src/OpenCvSharp/PInvoke/NativeMethods/NativeMethods.cs

@@ -27,11 +27,15 @@ public static partial class NativeMethods
         //public const string DllFfmpegX86 = "opencv_videoio_ffmpeg430";
         //public const string DllFfmpegX64 = "opencv_videoio_ffmpeg430_64";
 
-        private const UnmanagedType StringUnmanagedType =
-#if NETSTANDARD2_1 || NETCOREAPP2_1 || NET48
-            UnmanagedType.LPUTF8Str;
-#else
+        //private const UnmanagedType StringUnmanagedType = UnmanagedType.LPStr;
+
+        private const UnmanagedType StringUnmanagedTypeWindows = UnmanagedType.LPStr;
+
+        private const UnmanagedType StringUnmanagedTypeNotWindows =
+#if NET461 || NETSTANDARD2_0
             UnmanagedType.LPStr;
+#else
+            UnmanagedType.LPUTF8Str;
 #endif
 
         /// <summary>
@@ -53,8 +57,7 @@ static NativeMethods()
             TryPInvoke();
         }
 
-        // ReSharper disable once StringLiteralTypo
-        //[Conditional("DOTNETCORE")]
+#pragma warning disable CA1801
         public static void HandleException(ExceptionStatus status)
         {
 #if DOTNETCORE
@@ -63,9 +66,10 @@ public static void HandleException(ExceptionStatus status)
             {
                 ExceptionHandler.ThrowPossibleException();
             }
-#else            
+#else
 #endif
         }
+#pragma warning restore CA1801
 
         /// <summary>
         /// Load DLL files dynamically using Win32 LoadLibrary
@@ -102,6 +106,7 @@ public static void LoadLibraries(IEnumerable<string>? additionalPaths = null)
         /// </summary>
         public static void TryPInvoke()
         {
+#pragma warning disable CA1031
             if (tried)
                 return;
             tried = true;
@@ -144,6 +149,7 @@ public static void TryPInvoke()
                 catch { }
                 throw;
             }
+#pragma warning restore CA1031
         }
 
         /// <summary>
@@ -152,7 +158,11 @@ public static void TryPInvoke()
         /// <returns></returns>
         public static bool IsWindows()
         {
+#if NET461
             return !IsUnix();
+#else
+            return RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
+#endif
         }
 
         /// <summary>
@@ -161,11 +171,15 @@ public static bool IsWindows()
         /// <returns></returns>
         public static bool IsUnix()
         {
-#if DOTNET_FRAMEWORK
+#if NET461
             var p = Environment.OSVersion.Platform;
             return (p == PlatformID.Unix ||
                     p == PlatformID.MacOSX ||
                     (int)p == 128);
+#elif NETCOREAPP3_1
+            return RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ||
+                RuntimeInformation.IsOSPlatform(OSPlatform.OSX) || 
+                RuntimeInformation.IsOSPlatform(OSPlatform.FreeBSD);
 #else
             return RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ||
                 RuntimeInformation.IsOSPlatform(OSPlatform.OSX);
@@ -193,9 +207,11 @@ public static bool IsMono()
         public static readonly CvErrorCallback ErrorHandlerIgnorance =
             (status, funcName, errMsg, fileName, line, userData) => 0;
 
+#pragma warning disable CA2211
         /// <summary>
         /// Default error handler
         /// </summary>
         public static CvErrorCallback? ErrorHandlerDefault = null;
+#pragma warning restore CA2211
     }
 }

src/OpenCvSharp/PInvoke/NativeMethods/NativeMethods_imgcodecs.cs

@@ -8,21 +8,87 @@ namespace OpenCvSharp
 {
     static partial class NativeMethods
     {
-        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
-        public static extern ExceptionStatus imgcodecs_imread(
-            [MarshalAs(StringUnmanagedType)] string filename, int flags, out IntPtr returnValue);
+        // imread
 
-        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
-        public static extern ExceptionStatus imgcodecs_imreadmulti(
-            [MarshalAs(StringUnmanagedType)] string filename, IntPtr mats, int flags, out int returnValue);
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imread")]
+        public static extern ExceptionStatus imgcodecs_imread_NotWindows(
+            [MarshalAs(StringUnmanagedTypeNotWindows)] string fileName, int flags, out IntPtr returnValue);
 
-        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
-        public static extern ExceptionStatus imgcodecs_imwrite(
-            [MarshalAs(StringUnmanagedType)] string filename, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imread")]
+        public static extern ExceptionStatus imgcodecs_imread_Windows(
+            [MarshalAs(StringUnmanagedTypeWindows)] string fileName, int flags, out IntPtr returnValue);
+
+        [Pure]
+        public static ExceptionStatus imgcodecs_imread(string fileName, int flags, out IntPtr returnValue)
+        {
+            if (IsWindows())
+                return imgcodecs_imread_Windows(fileName, flags, out returnValue);
+            return imgcodecs_imread_NotWindows(fileName, flags, out returnValue);
+        }
+
+        // imreadmulti
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imreadmulti")]
+        public static extern ExceptionStatus imgcodecs_imreadmulti_NotWindows(
+            [MarshalAs(StringUnmanagedTypeNotWindows)] string fileName, IntPtr mats, int flags, out int returnValue);
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imreadmulti")]
+        public static extern ExceptionStatus imgcodecs_imreadmulti_Windows(
+            [MarshalAs(StringUnmanagedTypeWindows)] string fileName, IntPtr mats, int flags, out int returnValue);
+
+        [Pure]
+        public static ExceptionStatus imgcodecs_imreadmulti(string fileName, IntPtr mats, int flags, out int returnValue)
+        {
+            if (IsWindows())
+                return imgcodecs_imreadmulti_Windows(fileName, mats, flags, out returnValue);
+            return imgcodecs_imreadmulti_NotWindows(fileName, mats, flags, out returnValue);
+        }
+
+        // imwrite
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite")]
+        public static extern ExceptionStatus imgcodecs_imwrite_NotWindows(
+            [MarshalAs(StringUnmanagedTypeNotWindows)] string fileName, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite")]
+        public static extern ExceptionStatus imgcodecs_imwrite_Windows(
+            [MarshalAs(StringUnmanagedTypeWindows)] string fileName, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+
+        [Pure]
+        public static ExceptionStatus imgcodecs_imwrite(string fileName, IntPtr img, int[] @params, int paramsLength, out int returnValue)
+        {
+            if (IsWindows())
+                return imgcodecs_imwrite_Windows(fileName, img, @params, paramsLength, out returnValue);
+            return imgcodecs_imwrite_NotWindows(fileName, img, @params, paramsLength, out returnValue);
+        }
 
-        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true, CharSet = CharSet.Ansi)]
-        public static extern ExceptionStatus imgcodecs_imwrite_multi(
-            [MarshalAs(StringUnmanagedType)] string filename, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+        // imwrite_multi
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite_multi")]
+        public static extern ExceptionStatus imgcodecs_imwrite_multi_NotWindows(
+            [MarshalAs(StringUnmanagedTypeNotWindows)] string fileName, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite_multi")]
+        public static extern ExceptionStatus imgcodecs_imwrite_multi_Windows(
+            [MarshalAs(StringUnmanagedTypeWindows)] string fileName, IntPtr img, [In] int[] @params, int paramsLength, out int returnValue);
+
+        [Pure]
+        public static ExceptionStatus imgcodecs_imwrite_multi(string fileName, IntPtr img, int[] @params, int paramsLength, out int returnValue)
+        {
+            if (IsWindows())
+                return imgcodecs_imwrite_multi_Windows(fileName, img, @params, paramsLength, out returnValue);
+            return imgcodecs_imwrite_multi_NotWindows(fileName, img, @params, paramsLength, out returnValue);
+        }
+
+        // 
 
         [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, ExactSpelling = true)]
         public static extern ExceptionStatus imgcodecs_imdecode_Mat(
@@ -35,17 +101,36 @@ public static extern ExceptionStatus imgcodecs_imdecode_vector(
         [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, ExactSpelling = true)]
         public static extern ExceptionStatus imgcodecs_imdecode_InputArray(
             IntPtr buf, int flags, out IntPtr returnValue);
-
+
+        // Do not consider that "ext" may not be ASCII characters
         [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
         public static extern ExceptionStatus imgcodecs_imencode_vector(
-            [MarshalAs(StringUnmanagedType)] string ext, IntPtr img, IntPtr buf, [In] int[] @params, int paramsLength, out int returnValue);
+            [MarshalAs(UnmanagedType.LPStr)] string ext, IntPtr img, IntPtr buf, [In] int[] @params, int paramsLength, out int returnValue);
 
-        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
-        public static extern ExceptionStatus imgcodecs_haveImageReader(
-            [MarshalAs(StringUnmanagedType)] string fileName, out int returnValue);
+        // haveImageReader
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite")]
+        public static extern ExceptionStatus imgcodecs_haveImageReader_NotWindows(
+            [MarshalAs(StringUnmanagedTypeNotWindows)] string fileName, out int returnValue);
+
+        [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true,
+             EntryPoint = "imgcodecs_imwrite")]
+        public static extern ExceptionStatus imgcodecs_haveImageReader_Windows(
+            [MarshalAs(StringUnmanagedTypeWindows)] string fileName, out int returnValue);
+
+        [Pure]
+        public static ExceptionStatus imgcodecs_haveImageReader(string fileName, out int returnValue)
+        {
+            if (IsWindows())
+                return imgcodecs_haveImageReader_Windows(fileName, out returnValue);
+            return imgcodecs_haveImageReader_NotWindows(fileName, out returnValue);
+        }
 
+        // haveImageWriter
+
         [Pure, DllImport(DllExtern, CallingConvention = CallingConvention.Cdecl, BestFitMapping = false, ThrowOnUnmappableChar = true, ExactSpelling = true)]
         public static extern ExceptionStatus imgcodecs_haveImageWriter(
-            [MarshalAs(StringUnmanagedType)] string fileName, out int returnValue);
+            [MarshalAs(UnmanagedType.LPStr)] string fileName, out int returnValue);
     }
 }