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Unmanaged callback causing stack overflow

I work with an unmanaged resource with C #. The resource provides a callback that can be configured for specific events that may occur in hardware. To access unmanaged functions, I do the following:

[DllImportAttribute("testDLL.dll", EntryPoint = "InstallCallback")]
public static extern short InstallCallback(uint handle, byte x, byte y, IntFuncPtr ptr);

[UnmanagedFunctionPointer(CallingConvention.StdCall)]
public delegate void IntFuncPtr(uint handle, byte x, byte y, LogEntry info);

First, I set up a callback with a reference to the method that follows the IntFuncPtr delegate. Then I let the hardware do its job. After approximately 4700 callbacks, the application crashes. The callback works fine if I write code in c / C ++, but I can replicate it by removing __stdcall from my callback function. From C #, I cannot catch an error that indicates that the application is dying in an unmanaged resource. With a c / C ++ application, I see that the stack overflows without __stdcall.

I thought the delegate might not work with the stdcall calling convention, so I tried the following:

[DllImportAttribute("testDLL.dll", EntryPoint = "InstallCallback")]
public static extern short InstallCallback(uint handle, byte x, byte y, IntPtr ptr);

public delegate void IntFuncPtr(uint handle, byte x, byte y, LogEntry info);

var callBackDelegate = new IntFuncPtr(Callback);
var callBackPtr = Marshal.GetFunctionPointerForDelegate(callBackDelegate);
InstallCallback(handle, 1, 1, callBackPtr);

This also did not work.

, , , __stdcall. non __stdcall, . #, DllImport UnmanagedFunctionPointer stdcall. , # c/++, __stdcall.

#?

1:

, #.

extern "C" __declspec( dllexport ) short __stdcall InstallCallback(unsigned int handle, unsigned char x, unsigned char y, LOG_ENTRY info );

typedef union
{
    unsigned int ul_All;
    struct
    {
    unsigned int ul_Info:24;
    unsigned int uc_IntType:8;
    }t;

    struct
    {
    unsigned int ul_Info:24;

    unsigned int uc_Biu1:1;
    unsigned int uc_Biu2:1;
    unsigned int uc_Dma:1;
    unsigned int uc_Target:1;
    unsigned int uc_Cmd:1;
    unsigned int uc_Biu3:1;
    unsigned int uc_Biu4:1;
    unsigned int res:1;
    }b;
} LOG_ENTRY_C;

typedef union
{
    unsigned int All;
    struct
    {
    AiUInt32 Index:16;
    AiUInt32 Res:8;
    AiUInt32 IntSrc:8;
    }t;
} LOG_ENTRY_D;

typedef struct log_entry
{
    unsigned int a;
    unsigned int b;
    LOG_ENTRY_C c;
    LOG_ENTRY_D d;
} LOG_ENTRY;

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct LogEntry {
    public uint Lla;
    public uint Llb;
    public LogEntryC Llc;
    public LogEntryD Lld;
}

[StructLayoutAttribute(LayoutKind.Explicit)]
public struct LogEntryC {
    [FieldOffsetAttribute(0)]
    public uint All;
    [FieldOffsetAttribute(0)]
    public LogEntryCT t;
    [FieldOffsetAttribute(0)]
    public LogEntryCB b;
}

[StructLayoutAttribute(LayoutKind.Explicit)]
public struct LogEntryD {
    [FieldOffsetAttribute(0)]
    public uint All;
    [FieldOffsetAttribute(0)]
    public LogEntryDT t;
}

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct LogEntryCT {
    public uint bitvector1;
    public uint IntType {
        get { return ((uint)((this.bitvector1 & 255u))); }
        set { this.bitvector1 = ((uint)((value | this.bitvector1))); }
    }
    public uint Info {
        get { return ((uint)(((this.bitvector1 & 4294967040u) / 256))); }
        set { this.bitvector1 = ((uint)(((value * 256) | this.bitvector1))); }
    }
}
[StructLayoutAttribute(LayoutKind.Sequential)]
public struct LogEntryCB {
    public uint bitvector1;
    public uint res {
        get { return ((uint)((this.bitvector1 & 1u))); }
        set { this.bitvector1 = ((uint)((value | this.bitvector1))); }
    }
    public uint Biu4 {
        get { return ((uint)(((this.bitvector1 & 2u) / 2))); }
        set { this.bitvector1 = ((uint)(((value * 2) | this.bitvector1))); }
    }
    public uint Biu3 {
        get { return ((uint)(((this.bitvector1 & 4u) / 4))); }
        set { this.bitvector1 = ((uint)(((value * 4) | this.bitvector1))); }
    }
    public uint Cmd {
        get { return ((uint)(((this.bitvector1 & 8u) / 8))); }
        set { this.bitvector1 = ((uint)(((value * 8) | this.bitvector1))); }
    }
    public uint Target {
        get { return ((uint)(((this.bitvector1 & 16u) / 16))); }
        set { this.bitvector1 = ((uint)(((value * 16) | this.bitvector1))); }
    }
    public uint Dma {
        get { return ((uint)(((this.bitvector1 & 32u) / 32))); }
        set { this.bitvector1 = ((uint)(((value * 32) | this.bitvector1))); }
    }
    public uint Biu2 {
        get { return ((uint)(((this.bitvector1 & 64u) / 64))); }
        set { this.bitvector1 = ((uint)(((value * 64) | this.bitvector1))); }
    }
    public uint Biu1 {
        get { return ((uint)(((this.bitvector1 & 128u) / 128))); }
        set { this.bitvector1 = ((uint)(((value * 128) | this.bitvector1))); }
    }
    public uint Info {
        get { return ((uint)(((this.bitvector1 & 4294967040u) / 256))); }
        set { this.bitvector1 = ((uint)(((value * 256) | this.bitvector1))); }
    }
}

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct LogEntryDT {
    public uint bitvector1;
    public uint IntSrc {
        get { return ((uint)((this.bitvector1 & 255u))); }
        set { this.bitvector1 = ((uint)((value | this.bitvector1))); }
    }
    public uint Res {
        get { return ((uint)(((this.bitvector1 & 65280u) / 256))); }
        set { this.bitvector1 = ((uint)(((value * 256) | this.bitvector1))); }
    }
    public uint Index {
        get { return ((uint)(((this.bitvector1 & 4294901760u) / 65536))); }
        set { this.bitvector1 = ((uint)(((value * 65536) | this.bitvector1))); }
    }
}
+5
2

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+1

[DllImportAttribute("testDLL.dll", EntryPoint = "InstallCallback", CallingConvention=CallingConvention.StdCall) ]
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