Convert GetAllMountPoints to UnmanagedCallersOnly

src/libraries/Common/src/Interop/Unix/System.Native/Interop.MountPoints.cs

@@ -2,37 +2,54 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Runtime.ExceptionServices;
 using System.Runtime.InteropServices;
 
 internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
-        private unsafe delegate void MountPointFound(byte* name);
+        [LibraryImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetAllMountPoints")]
+        private static unsafe partial int GetAllMountPoints(delegate* unmanaged<void*, byte*, void> onFound, void* context);
 
-        [LibraryImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetAllMountPoints", SetLastError = true)]
-        private static partial int GetAllMountPoints(MountPointFound mpf);
+        private struct AllMountPointsContext
+        {
+            public List<string> _results;
+            public ExceptionDispatchInfo? _exception;
+        }
+
+        [UnmanagedCallersOnly]
+        private static unsafe void AddMountPoint(void* context, byte* name)
+        {
+            ref AllMountPointsContext callbackContext = ref Unsafe.As<byte, AllMountPointsContext>(ref *(byte*)context);
+            callbackContext._results = new List<string>();
+
+            try
+            {
+                callbackContext._results.Add(Marshal.PtrToStringUTF8((IntPtr)name)!);
+            }
+            catch (Exception e)
+            {
+                callbackContext._exception = ExceptionDispatchInfo.Capture(e);
+            }
+        }
 
         internal static string[] GetAllMountPoints()
         {
-            int count = 0;
-            var found = new string[4];
+            AllMountPointsContext context = default;
+            context._results = new List<string>();
 
             unsafe
             {
-                GetAllMountPoints((byte* name) =>
-                {
-                    if (count == found.Length)
-                    {
-                        Array.Resize(ref found, count * 2);
-                    }
-                    found[count++] = Marshal.PtrToStringAnsi((IntPtr)name)!;
-                });
+                GetAllMountPoints(&AddMountPoint, Unsafe.AsPointer(ref context));
             }
 
-            Array.Resize(ref found, count);
-            return found;
+            if (context._exception != null)
+                context._exception.Throw();
+
+            return context._results.ToArray();
         }
     }
 }

src/libraries/Common/src/Interop/Windows/HttpApi/Interop.HttpApi.cs

@@ -459,7 +459,7 @@ internal struct HTTP_BINDING_INFO
         internal static partial uint HttpInitialize(HTTPAPI_VERSION version, uint flags, IntPtr pReserved);
 
         [LibraryImport(Libraries.HttpApi, SetLastError = true)]
-        internal static partial uint HttpSetUrlGroupProperty(ulong urlGroupId, HTTP_SERVER_PROPERTY serverProperty, IntPtr pPropertyInfo, uint propertyInfoLength);
+        internal static unsafe partial uint HttpSetUrlGroupProperty(ulong urlGroupId, HTTP_SERVER_PROPERTY serverProperty, void* pPropertyInfo, uint propertyInfoLength);
 
         [LibraryImport(Libraries.HttpApi, SetLastError = true)]
         internal static unsafe partial uint HttpCreateServerSession(HTTPAPI_VERSION version, ulong* serverSessionId, uint reserved);

src/libraries/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj

@@ -71,6 +71,7 @@
              Link="Common\Interop\Unix\Interop.MountPoints.FormatInfo.cs" />
   </ItemGroup>
   <ItemGroup>
+    <Reference Include="System.Collections" />
     <Reference Include="System.Memory" />
     <Reference Include="System.Runtime" />
     <Reference Include="System.Runtime.InteropServices" />

src/libraries/System.Net.HttpListener/src/System/Net/Windows/HttpListener.Windows.cs

@@ -90,10 +90,10 @@ public bool UnsafeConnectionNtlmAuthentication
         private Dictionary<ulong, DisconnectAsyncResult> DisconnectResults =>
             LazyInitializer.EnsureInitialized(ref _disconnectResults, () => new Dictionary<ulong, DisconnectAsyncResult>());
 
-        private void SetUrlGroupProperty(Interop.HttpApi.HTTP_SERVER_PROPERTY property, IntPtr info, uint infosize)
+        private unsafe void SetUrlGroupProperty(Interop.HttpApi.HTTP_SERVER_PROPERTY property, void* info, uint infosize)
         {
             Debug.Assert(_urlGroupId != 0, "SetUrlGroupProperty called with invalid url group id");
-            Debug.Assert(info != IntPtr.Zero, "SetUrlGroupProperty called with invalid pointer");
+            Debug.Assert(info != null, "SetUrlGroupProperty called with invalid pointer");
 
             //
             // Set the url group property using Http Api.
@@ -128,11 +128,9 @@ internal void SetServerTimeout(int[] timeouts, uint minSendBytesPerSecond)
                 (ushort)timeouts[(int)Interop.HttpApi.HTTP_TIMEOUT_TYPE.HeaderWait];
             timeoutinfo.MinSendRate = minSendBytesPerSecond;
 
-            IntPtr infoptr = new IntPtr(&timeoutinfo);
-
             SetUrlGroupProperty(
                 Interop.HttpApi.HTTP_SERVER_PROPERTY.HttpServerTimeoutsProperty,
-                infoptr, (uint)sizeof(Interop.HttpApi.HTTP_TIMEOUT_LIMIT_INFO));
+                &timeoutinfo, (uint)sizeof(Interop.HttpApi.HTTP_TIMEOUT_LIMIT_INFO));
         }
 
         public HttpListenerTimeoutManager TimeoutManager
@@ -307,10 +305,8 @@ private void AttachRequestQueueToUrlGroup()
             info.Flags = Interop.HttpApi.HTTP_FLAGS.HTTP_PROPERTY_FLAG_PRESENT;
             info.RequestQueueHandle = _currentSession!.RequestQueueHandle.DangerousGetHandle();
 
-            IntPtr infoptr = new IntPtr(&info);
-
             SetUrlGroupProperty(Interop.HttpApi.HTTP_SERVER_PROPERTY.HttpServerBindingProperty,
-                infoptr, (uint)sizeof(Interop.HttpApi.HTTP_BINDING_INFO));
+                &info, (uint)sizeof(Interop.HttpApi.HTTP_BINDING_INFO));
         }
 
         private void DetachRequestQueueFromUrlGroup()
@@ -328,11 +324,9 @@ private void DetachRequestQueueFromUrlGroup()
             info.Flags = Interop.HttpApi.HTTP_FLAGS.NONE;
             info.RequestQueueHandle = IntPtr.Zero;
 
-            IntPtr infoptr = new IntPtr(&info);
-
             uint statusCode = Interop.HttpApi.HttpSetUrlGroupProperty(_urlGroupId,
                 Interop.HttpApi.HTTP_SERVER_PROPERTY.HttpServerBindingProperty,
-                infoptr, (uint)sizeof(Interop.HttpApi.HTTP_BINDING_INFO));
+                &info, (uint)sizeof(Interop.HttpApi.HTTP_BINDING_INFO));
 
             if (statusCode != Interop.HttpApi.ERROR_SUCCESS)
             {

src/native/libs/System.Native/pal_mount.c

@@ -29,7 +29,7 @@
 #endif
 #endif
 
-int32_t SystemNative_GetAllMountPoints(MountPointFound onFound)
+int32_t SystemNative_GetAllMountPoints(MountPointFound onFound, void* context)
 {
 #if HAVE_MNTINFO
     // getmntinfo returns pointers to OS-internal structs, so we don't need to worry about free'ing the object
@@ -41,7 +41,7 @@ int32_t SystemNative_GetAllMountPoints(MountPointFound onFound)
     int count = getmntinfo(&mounts, MNT_WAIT);
     for (int32_t i = 0; i < count; i++)
     {
-        onFound(mounts[i].f_mntonname);
+        onFound(context, mounts[i].f_mntonname);
     }
 
     return 0;
@@ -56,7 +56,7 @@ int32_t SystemNative_GetAllMountPoints(MountPointFound onFound)
         struct mnttab entry;
         while(getmntent(fp, &entry) == 0)
         {
-            onFound(entry.mnt_mountp);
+            onFound(context, entry.mnt_mountp);
         }
 
         result = fclose(fp);
@@ -79,7 +79,7 @@ int32_t SystemNative_GetAllMountPoints(MountPointFound onFound)
         struct mntent entry;
         while (getmntent_r(fp, &entry, buffer, STRING_BUFFER_SIZE) != NULL)
         {
-            onFound(entry.mnt_dir);
+            onFound(context, entry.mnt_dir);
         }
 
         result = endmntent(fp);

src/native/libs/System.Native/pal_mount.h

@@ -21,7 +21,7 @@ typedef struct
  * Using the callback pattern allows us to limit the number of allocs we do and makes it
  * cleaner on the managed side since we don't have to worry about cleaning up any unmanaged memory.
  */
-typedef void (*MountPointFound)(const char* name);
+typedef void (*MountPointFound)(void* context, const char* name);
 
 /**
  * Gets the space information for the given mount point and populates the input struct with the data.
@@ -45,4 +45,4 @@ PALEXPORT int32_t SystemNative_GetFormatInfoForMountPoint(
  * function pointer once-per-mount-point to prevent heap allocs
  * as much as possible.
  */
-PALEXPORT int32_t SystemNative_GetAllMountPoints(MountPointFound onFound);
+PALEXPORT int32_t SystemNative_GetAllMountPoints(MountPointFound onFound, void* context);