Backed out changeset c034b967d740 (bug 1571247) for perma failures on test_DownloadsCommon_getMimeInfo.js. CLOSED TREE

uriloader/exthandler/nsExternalHelperAppService.cpp

@@ -487,7 +487,7 @@ static const nsExtraMimeTypeEntry extraMimeEntries[] = {
     {IMAGE_BMP, "bmp", "BMP Image"},
     {IMAGE_GIF, "gif", "GIF Image"},
     {IMAGE_ICO, "ico,cur", "ICO Image"},
-    {IMAGE_JPEG, "jpg,jpeg,jfif,pjpeg,pjp", "JPEG Image"},
+    {IMAGE_JPEG, "jpeg,jpg,jfif,pjpeg,pjp", "JPEG Image"},
     {IMAGE_PNG, "png", "PNG Image"},
     {IMAGE_APNG, "apng", "APNG Image"},
     {IMAGE_TIFF, "tiff,tif", "TIFF Image"},
@@ -528,9 +528,6 @@ static const nsExtraMimeTypeEntry extraMimeEntries[] = {
     {AUDIO_MIDI, "mid", "Standard MIDI Audio"},
     {APPLICATION_WASM, "wasm", "WebAssembly Module"}};
 
-static const nsDefaultMimeTypeEntry sForbiddenPrimaryExtensions[] = {
-    {IMAGE_JPEG, "jfif"}};
-
 /**
  * File extensions for which decoding should be disabled.
  * NOTE: These MUST be lower-case and ASCII.
@@ -2634,18 +2631,6 @@ NS_IMETHODIMP nsExternalHelperAppService::GetFromTypeAndExtension(
     LOG(("Falling back to 'File' file description\n"));
   }
 
-  // Sometimes, OSes give us bad data. We have a set of forbidden extensions
-  // for some MIME types. If the primary extension is forbidden,
-  // overwrite it with a known-good one. See bug 1571247 for context.
-  nsAutoCString primaryExtension;
-  (*_retval)->GetPrimaryExtension(primaryExtension);
-  if (!primaryExtension.LowerCaseEqualsASCII(
-          PromiseFlatCString(aFileExt).get())) {
-    if (MaybeReplacePrimaryExtension(primaryExtension, *_retval)) {
-      (*_retval)->GetPrimaryExtension(primaryExtension);
-    }
-  }
-
   // Finally, check if we got a file extension and if yes, if it is an
   // extension on the mimeinfo, in which case we want it to be the primary one
   if (!aFileExt.IsEmpty()) {
@@ -2657,7 +2642,6 @@ NS_IMETHODIMP nsExternalHelperAppService::GetFromTypeAndExtension(
       nsAutoCString fileExt;
       ToLowerCase(aFileExt, fileExt);
       (*_retval)->SetPrimaryExtension(fileExt);
-      primaryExtension = fileExt;
     }
   }
 
@@ -2665,7 +2649,9 @@ NS_IMETHODIMP nsExternalHelperAppService::GetFromTypeAndExtension(
   // type is in our list; these are file formats supported by Firefox and
   // we don't want other brands positioning themselves as the sole viewer
   // for a system.
-  if (!primaryExtension.IsEmpty()) {
+  nsAutoCString primaryExtension;
+  rv = (*_retval)->GetPrimaryExtension(primaryExtension);
+  if (NS_SUCCEEDED(rv)) {
     for (const char* ext : descriptionOverwriteExtensions) {
       if (primaryExtension.Equals(ext)) {
         nsCOMPtr<nsIStringBundleService> bundleService =
@@ -2694,8 +2680,10 @@ NS_IMETHODIMP nsExternalHelperAppService::GetFromTypeAndExtension(
     nsAutoCString type;
     (*_retval)->GetMIMEType(type);
 
+    nsAutoCString ext;
+    (*_retval)->GetPrimaryExtension(ext);
     LOG(("MIME Info Summary: Type '%s', Primary Ext '%s'\n", type.get(),
-         primaryExtension.get()));
+         ext.get()));
   }
 
   return NS_OK;
@@ -2902,26 +2890,6 @@ nsresult nsExternalHelperAppService::FillMIMEInfoForExtensionFromExtras(
   return FillMIMEInfoForMimeTypeFromExtras(type, true, aMIMEInfo);
 }
 
-bool nsExternalHelperAppService::MaybeReplacePrimaryExtension(
-    const nsACString& aPrimaryExtension, nsIMIMEInfo* aMIMEInfo) {
-  for (const auto& entry : sForbiddenPrimaryExtensions) {
-    if (aPrimaryExtension.LowerCaseEqualsASCII(entry.mFileExtension)) {
-      nsDependentCString mime(entry.mMimeType);
-      for (const auto& extraEntry : extraMimeEntries) {
-        if (mime.LowerCaseEqualsASCII(extraEntry.mMimeType)) {
-          nsDependentCString goodExts(extraEntry.mFileExtensions);
-          int32_t commaPos = goodExts.FindChar(',');
-          commaPos = commaPos == kNotFound ? goodExts.Length() : commaPos;
-          auto goodExt = Substring(goodExts, 0, commaPos);
-          aMIMEInfo->SetPrimaryExtension(goodExt);
-          return true;
-        }
-      }
-    }
-  }
-  return false;
-}
-
 bool nsExternalHelperAppService::GetTypeFromExtras(const nsACString& aExtension,
                                                    nsACString& aMIMEType) {
   NS_ASSERTION(!aExtension.IsEmpty(), "Empty aExtension parameter!");

uriloader/exthandler/nsExternalHelperAppService.h

@@ -143,14 +143,6 @@ class nsExternalHelperAppService : public nsIExternalHelperAppService,
   nsresult FillMIMEInfoForExtensionFromExtras(const nsACString& aExtension,
                                               nsIMIMEInfo* aMIMEInfo);
 
-  /**
-   * Replace the primary extension of the mimeinfo object if it's in our
-   * list of forbidden extensions. This fixes up broken information
-   * provided to us by the OS.
-   */
-  bool MaybeReplacePrimaryExtension(const nsACString& aPrimaryExtension,
-                                    nsIMIMEInfo* aMIMEInfo);
-
   /**
    * Searches the "extra" array for a MIME type, and gets its extension.
    * @param aExtension The extension to search for