1 files changed, 36 insertions, 39 deletions

diff --git a/components/jar/src/nsJARChannel.cpp b/components/jar/src/nsJARChannel.cpp
index 0bbfa31eb..65c034779 100644
--- a/components/jar/src/nsJARChannel.cpp
+++ b/components/jar/src/nsJARChannel.cpp
@@ -577,47 +577,48 @@ nsJARChannel::GetSecurityInfo(nsISupports **aSecurityInfo)
     return NS_OK;
 }
 
-bool nsJARChannel::GetContentTypeGuess(nsACString& aResult) const {
-  const char *ext = nullptr, *fileName = mJarEntry.get();
-  int32_t len = mJarEntry.Length();
-
-  // check if we're displaying a directory
-  // mJarEntry will be empty if we're trying to display
-  // the topmost directory in a zip, e.g. jar:foo.zip!/
-  if (ENTRY_IS_DIRECTORY(mJarEntry)) {
-    aResult.AssignLiteral(APPLICATION_HTTP_INDEX_FORMAT);
-    return true;
-  }
-
-  // Not a directory, take a guess by its extension
-  for (int32_t i = len - 1; i >= 0; i--) {
-    if (fileName[i] == '.') {
-      ext = &fileName[i + 1];
-      break;
-    }
-  }
-  if (!ext) {
-    return false;
-  }
-  nsIMIMEService* mimeServ = gJarHandler->MimeService();
-  if (!mimeServ) {
-    return false;
-  }
-  mimeServ->GetTypeFromExtension(nsDependentCString(ext), aResult);
-  return !aResult.IsEmpty();
-}
-
 NS_IMETHODIMP
-nsJARChannel::GetContentType(nsACString &aResult)
+nsJARChannel::GetContentType(nsACString &result)
 {
     // If the Jar file has not been open yet,
     // We return application/x-unknown-content-type
     if (!mOpened) {
-      aResult.Assign(UNKNOWN_CONTENT_TYPE);
+      result.Assign(UNKNOWN_CONTENT_TYPE);
       return NS_OK;
     }
 
-    aResult = mContentType;
+    if (mContentType.IsEmpty()) {
+
+        //
+        // generate content type and set it
+        //
+        const char *ext = nullptr, *fileName = mJarEntry.get();
+        int32_t len = mJarEntry.Length();
+
+        // check if we're displaying a directory
+        // mJarEntry will be empty if we're trying to display
+        // the topmost directory in a zip, e.g. jar:foo.zip!/
+        if (ENTRY_IS_DIRECTORY(mJarEntry)) {
+            mContentType.AssignLiteral(APPLICATION_HTTP_INDEX_FORMAT);
+        }
+        else {
+            // not a directory, take a guess by its extension
+            for (int32_t i = len-1; i >= 0; i--) {
+                if (fileName[i] == '.') {
+                    ext = &fileName[i + 1];
+                    break;
+                }
+            }
+            if (ext) {
+                nsIMIMEService *mimeServ = gJarHandler->MimeService();
+                if (mimeServ)
+                    mimeServ->GetTypeFromExtension(nsDependentCString(ext), mContentType);
+            }
+            if (mContentType.IsEmpty())
+                mContentType.AssignLiteral(UNKNOWN_CONTENT_TYPE);
+        }
+    }
+    result = mContentType;
     return NS_OK;
 }
 
@@ -635,8 +636,8 @@ nsJARChannel::SetContentType(const nsACString &aContentType)
 NS_IMETHODIMP
 nsJARChannel::GetContentCharset(nsACString &aContentCharset)
 {
-    // We behave like HTTP channels (treat this as a hint if called before open,
-    // and override the charset if called after open).
+    // If someone gives us a charset hint we should just use that charset.
+    // So we don't care when this is being called.
     aContentCharset = mContentCharset;
     return NS_OK;
 }
@@ -729,10 +730,6 @@ nsJARChannel::Open(nsIInputStream **stream)
 
     input.forget(stream);
     mOpened = true;
-    // Compute the content type now.
-    if (!GetContentTypeGuess(mContentType)) {
-        mContentType.Assign(UNKNOWN_CONTENT_TYPE);
-    }
     // local files are always considered safe
     mIsUnsafe = false;
     return NS_OK;