From f95f57c3c2a5fbaa09a543f5475c01c0ec66f098 Mon Sep 17 00:00:00 2001
From: Xidorn Quan <me@upsuper.org>
Date: Fri, 12 Aug 2016 20:56:23 +1000
Subject: [PATCH] Bug 306471 part 1 - Some code style cleanup for
 nsExternalHelperAppService::GetTypeFromExtension. r=bz

MozReview-Commit-ID: 3N37Kd2fNjS

--HG--
extra : rebase_source : 825308563f4d1ebdb3e672d088975df30bf89392
---
 .../exthandler/nsExternalHelperAppService.cpp | 52 +++++++++++--------
 1 file changed, 29 insertions(+), 23 deletions(-)

diff --git a/uriloader/exthandler/nsExternalHelperAppService.cpp b/uriloader/exthandler/nsExternalHelperAppService.cpp
index 839aa1ae7b13..1ae3f7b7a41f 100644
--- a/uriloader/exthandler/nsExternalHelperAppService.cpp
+++ b/uriloader/exthandler/nsExternalHelperAppService.cpp
@@ -2722,7 +2722,9 @@ NS_IMETHODIMP nsExternalHelperAppService::GetFromTypeAndExtension(const nsACStri
   return NS_OK;
 }
 
-NS_IMETHODIMP nsExternalHelperAppService::GetTypeFromExtension(const nsACString& aFileExt, nsACString& aContentType) 
+NS_IMETHODIMP
+nsExternalHelperAppService::GetTypeFromExtension(const nsACString& aFileExt,
+                                                 nsACString& aContentType)
 {
   // OK. We want to try the following sources of mimetype information, in this order:
   // 1. defaultMimeEntries array
@@ -2733,36 +2735,39 @@ NS_IMETHODIMP nsExternalHelperAppService::GetTypeFromExtension(const nsACString&
   // 6. The "ext-to-type-mapping" category
 
   // Early return if called with an empty extension parameter
-  if (aFileExt.IsEmpty())
+  if (aFileExt.IsEmpty()) {
     return NS_ERROR_NOT_AVAILABLE;
+  }
 
-  nsresult rv = NS_OK;
   // First of all, check our default entries
-  for (size_t i = 0; i < ArrayLength(defaultMimeEntries); i++)
-  {
-    if (aFileExt.LowerCaseEqualsASCII(defaultMimeEntries[i].mFileExtension)) {
-      aContentType = defaultMimeEntries[i].mMimeType;
-      return rv;
+  for (auto& entry : defaultMimeEntries) {
+    if (aFileExt.LowerCaseEqualsASCII(entry.mFileExtension)) {
+      aContentType = entry.mMimeType;
+      return NS_OK;
     }
   }
 
   // Check user-set prefs
   nsCOMPtr<nsIHandlerService> handlerSvc = do_GetService(NS_HANDLERSERVICE_CONTRACTID);
-  if (handlerSvc)
-    rv = handlerSvc->GetTypeFromExtension(aFileExt, aContentType);
-  if (NS_SUCCEEDED(rv) && !aContentType.IsEmpty())
-    return NS_OK;
+  if (handlerSvc) {
+    nsresult rv = handlerSvc->GetTypeFromExtension(aFileExt, aContentType);
+    if (NS_SUCCEEDED(rv) && !aContentType.IsEmpty()) {
+      return NS_OK;
+    }
+  }
 
   // Ask OS.
   bool found = false;
   nsCOMPtr<nsIMIMEInfo> mi = GetMIMEInfoFromOS(EmptyCString(), aFileExt, &found);
-  if (mi && found)
+  if (mi && found) {
     return mi->GetMIMEType(aContentType);
+  }
 
   // Check extras array.
   found = GetTypeFromExtras(aFileExt, aContentType);
-  if (found)
+  if (found) {
     return NS_OK;
+  }
 
   // Try the plugins
   RefPtr<nsPluginHost> pluginHost = nsPluginHost::GetInst();
@@ -2771,24 +2776,25 @@ NS_IMETHODIMP nsExternalHelperAppService::GetTypeFromExtension(const nsACString&
     return NS_OK;
   }
 
-  rv = NS_OK;
   // Let's see if an extension added something
-  nsCOMPtr<nsICategoryManager> catMan(do_GetService("@mozilla.org/categorymanager;1"));
+  nsCOMPtr<nsICategoryManager> catMan(
+    do_GetService("@mozilla.org/categorymanager;1"));
   if (catMan) {
     // The extension in the category entry is always stored as lowercase
     nsAutoCString lowercaseFileExt(aFileExt);
     ToLowerCase(lowercaseFileExt);
     // Read the MIME type from the category entry, if available
     nsXPIDLCString type;
-    rv = catMan->GetCategoryEntry("ext-to-type-mapping", lowercaseFileExt.get(),
-                                  getter_Copies(type));
-    aContentType = type;
-  }
-  else {
-    rv = NS_ERROR_NOT_AVAILABLE;
+    nsresult rv = catMan->GetCategoryEntry("ext-to-type-mapping",
+                                           lowercaseFileExt.get(),
+                                           getter_Copies(type));
+    if (NS_SUCCEEDED(rv)) {
+      aContentType = type;
+      return NS_OK;
+    }
   }
 
-  return rv;
+  return NS_ERROR_NOT_AVAILABLE;
 }
 
 NS_IMETHODIMP nsExternalHelperAppService::GetPrimaryExtension(const nsACString& aMIMEType, const nsACString& aFileExt, nsACString& _retval)