Better Semaphore fix

Former-commit-id: c679e15305cade71e0fec7d3db7f0eab41224741

src/ImageProcessor.Web/NET45/HttpModules/ImageProcessingModule.cs

@@ -385,16 +385,14 @@ namespace ImageProcessor.Web.HttpModules
                             if (isRemote)
                             {
                                 SemaphoreSlim semaphore = GetSemaphoreSlim(cachedPath);
+#if NET45
+                                await semaphore.WaitAsync();
+#else
+                                semaphore.Wait();
+#endif
                                 try
                                 {
-                                    // This should not happen :(  
-                                    if (semaphore != null)
-                                    {
-                                        semaphore.Wait();
-                                    }
-
                                     Uri uri = new Uri(requestPath + "?" + urlParameters);
-
                                     RemoteFile remoteFile = new RemoteFile(uri, false);
 
                                     // Prevent response blocking.
@@ -432,25 +430,20 @@ namespace ImageProcessor.Web.HttpModules
                                     }
                                 }
                                 finally
-                                {
-                                    // This should not happen :(  
-                                    if (semaphore != null)
                                 {
                                     semaphore.Release();
                                 }
                             }
-                            }
                             else
                             {
                                 SemaphoreSlim semaphore = GetSemaphoreSlim(cachedPath);
+#if NET45
+                                await semaphore.WaitAsync();
+#else
+                                semaphore.Wait();
+#endif
                                 try
                                 {
-                                    // This should not happen :(  
-                                    if (semaphore != null)
-                                    {
-                                        semaphore.Wait();
-                                    }
-
                                     // Check to see if the file exists.
                                     // ReSharper disable once AssignNullToNotNullAttribute
                                     FileInfo fileInfo = new FileInfo(requestPath);
@@ -475,16 +468,12 @@ namespace ImageProcessor.Web.HttpModules
                                     await cache.TrimCachedFolderAsync(cachedPath);
                                 }
                                 finally
-                                {
-                                    // This should not happen :(  
-                                    if (semaphore != null)
                                 {
                                     semaphore.Release();
                                 }
                             }
                         }
                     }
-                    }
 
                     string incomingEtag = context.Request.Headers["If-None-Match"];
 

src/TestWebsites/NET45/Test_Website_NET45/Web.config

@@ -6,17 +6,17 @@
 
 <configuration>
   <configSections>
-    <!--<sectionGroup name="imageProcessor">
+    <sectionGroup name="imageProcessor">
       <section name="security" requirePermission="false" type="ImageProcessor.Web.Configuration.ImageSecuritySection, ImageProcessor.Web"/>
       <section name="processing" requirePermission="false" type="ImageProcessor.Web.Configuration.ImageProcessingSection, ImageProcessor.Web"/>
       <section name="cache" requirePermission="false" type="ImageProcessor.Web.Configuration.ImageCacheSection, ImageProcessor.Web"/>
-    </sectionGroup>-->
+    </sectionGroup>
   </configSections>
-  <!--<imageProcessor >
+  <imageProcessor >
     <security configSource="config\imageprocessor\security.config"/>
     <cache configSource="config\imageprocessor\cache.config"/>
     <processing configSource="config\imageprocessor\processing.config"/>
-  </imageProcessor>-->
+  </imageProcessor>
   <appSettings>
     <add key="webpages:Version" value="2.0.0.0" />
     <add key="webpages:Enabled" value="false" />