VSB #1

danmoseley · Sep 2, 2018 · bd9db82 · bd9db82
1 parent 04d0c1a
commit bd9db82
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Showing 3 changed files with 22 additions and 19 deletions.
diff --git a/src/Common/src/CoreLib/System/Text/ValueStringBuilder.cs b/src/Common/src/CoreLib/System/Text/ValueStringBuilder.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Buffers;
 using System.Diagnostics;
 using System.Runtime.CompilerServices;

diff --git a/src/Common/src/Interop/Windows/advapi32/Interop.GetServiceDisplayName.cs b/src/Common/src/Interop/Windows/advapi32/Interop.GetServiceDisplayName.cs
@@ -6,39 +6,36 @@
 using System;
 using System.Buffers;
 using System.Runtime.InteropServices;
+using System.Text;
 
 internal partial class Interop
 {
     internal partial class Advapi32
     {
         [DllImport(Libraries.Advapi32, EntryPoint = "GetServiceDisplayNameW", CharSet = System.Runtime.InteropServices.CharSet.Unicode, SetLastError = true)]
-        private static extern bool GetServiceDisplayNamePrivate(SafeServiceHandle SCMHandle, string serviceName, char[] displayName, ref int displayNameLength);
+        private static extern bool GetServiceDisplayNamePrivate(SafeServiceHandle SCMHandle, string serviceName, ref char displayName, ref int displayNameLength);
 
-        public static string GetServiceDisplayName(SafeServiceHandle SCMHandle, string serviceName)
+        public static unsafe string GetServiceDisplayName(SafeServiceHandle SCMHandle, string serviceName)
         {
-            // Get the size of buffer required
-            int bufLen = 0;
-            bool success = GetServiceDisplayNamePrivate(SCMHandle, serviceName, null, ref bufLen);
-            char[] buffer = null;
-
-            if (!success && Marshal.GetLastWin32Error() == Interop.Errors.ERROR_INSUFFICIENT_BUFFER)
+            var builder = new ValueStringBuilder(4096);
+            int bufLen;
+            while (true)
             {
-                bufLen++; // Does not include null
-                buffer = ArrayPool<char>.Shared.Rent(bufLen);
+                bufLen = builder.Capacity;
+                if (GetServiceDisplayNamePrivate(SCMHandle, serviceName, ref builder.GetPinnableReference(), ref bufLen))
+                    break;
 
-                try
-                {
-                    success = GetServiceDisplayNamePrivate(SCMHandle, serviceName, buffer, ref bufLen);
-                    if (success)
-                        return new string(buffer, 0, bufLen);
-                }
-                finally
+                int lastError = Marshal.GetLastWin32Error();
+                if (lastError != Interop.Errors.ERROR_INSUFFICIENT_BUFFER)
                 {
-                    ArrayPool<char>.Shared.Return(buffer);
+                    return null; // Caller may want to try something else
                 }
+
+                builder.EnsureCapacity(bufLen + 1); // Does not include null
             }
 
-            return null;
+            builder.Length = bufLen;
+            return builder.ToString();
         }
     }
 }
diff --git a/...ystem.ServiceProcess.ServiceController/src/System.ServiceProcess.ServiceController.csproj b/...ystem.ServiceProcess.ServiceController/src/System.ServiceProcess.ServiceController.csproj
@@ -12,6 +12,9 @@
     <Configurations>net461-Windows_NT-Debug;net461-Windows_NT-Release;netcoreapp-Windows_NT-Debug;netcoreapp-Windows_NT-Release;netfx-Windows_NT-Debug;netfx-Windows_NT-Release;netstandard-Debug;netstandard-Release;netstandard-Windows_NT-Debug;netstandard-Windows_NT-Release</Configurations>
   </PropertyGroup>
   <ItemGroup Condition="$(TargetGroup.StartsWith('netcoreapp')) OR ('$(TargetGroup)' == 'netstandard' AND '$(TargetsWindows)' == 'true')">
+    <Compile Include="$(CommonPath)\CoreLib\System\Text\ValueStringBuilder.cs">
+      <Link>Common\CoreLib\System\Text\ValueStringBuilder.cs</Link>
+    </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.Libraries.cs">
       <Link>Common\Interop\Windows\Interop.Libraries.cs</Link>
     </Compile>
@@ -108,8 +111,10 @@
     <Reference Include="System.ComponentModel.Primitives" />
     <Reference Include="System.Diagnostics.Debug" />
     <Reference Include="System.Diagnostics.Tools" />
+    <Reference Include="System.Memory" />
     <Reference Include="System.Resources.ResourceManager" />
     <Reference Include="System.Runtime" />
+    <Reference Include="System.Runtime.Extensions" />
     <Reference Include="System.Runtime.InteropServices" />
     <Reference Include="System.Threading" />
     <Reference Include="System.Threading.Thread" />