Bug 571074 - Mark nsITransferable.getTransferData as [must_use]. r=mats

Differential Revision: https://phabricator.services.mozilla.com/D13454

--HG--
extra : moz-landing-system : lando

dom/base/nsContentAreaDragDrop.cpp

@@ -241,7 +241,9 @@ nsContentAreaDragDropDataProvider::GetFlavorData(nsITransferable *aTransferable,
     // get the URI from the kFilePromiseURLMime flavor
     NS_ENSURE_ARG(aTransferable);
     nsCOMPtr<nsISupports> tmp;
-    aTransferable->GetTransferData(kFilePromiseURLMime, getter_AddRefs(tmp));
+    rv = aTransferable->GetTransferData(kFilePromiseURLMime,
+                                        getter_AddRefs(tmp));
+    NS_ENSURE_SUCCESS(rv, rv);
     nsCOMPtr<nsISupportsString> supportsString =
       do_QueryInterface(tmp);
     if (!supportsString)
@@ -256,8 +258,9 @@ nsContentAreaDragDropDataProvider::GetFlavorData(nsITransferable *aTransferable,
     rv = NS_NewURI(getter_AddRefs(sourceURI), sourceURLString);
     NS_ENSURE_SUCCESS(rv, rv);
 
-    aTransferable->GetTransferData(kFilePromiseDestFilename,
-                                   getter_AddRefs(tmp));
+    rv = aTransferable->GetTransferData(kFilePromiseDestFilename,
+                                        getter_AddRefs(tmp));
+    NS_ENSURE_SUCCESS(rv, rv);
     supportsString = do_QueryInterface(tmp);
     if (!supportsString)
       return NS_ERROR_FAILURE;
@@ -275,8 +278,9 @@ nsContentAreaDragDropDataProvider::GetFlavorData(nsITransferable *aTransferable,
     // because sandboxing blocks access to MIME-handler info from
     // content processes.
     if (XRE_IsParentProcess()) {
-      aTransferable->GetTransferData(kImageRequestMime,
-                                     getter_AddRefs(tmp));
+      rv = aTransferable->GetTransferData(kImageRequestMime,
+                                          getter_AddRefs(tmp));
+      NS_ENSURE_SUCCESS(rv, rv);
       supportsString = do_QueryInterface(tmp);
       if (!supportsString)
         return NS_ERROR_FAILURE;
@@ -324,8 +328,9 @@ nsContentAreaDragDropDataProvider::GetFlavorData(nsITransferable *aTransferable,
     // get the target directory from the kFilePromiseDirectoryMime
     // flavor
     nsCOMPtr<nsISupports> dirPrimitive;
-    aTransferable->GetTransferData(kFilePromiseDirectoryMime,
-                                   getter_AddRefs(dirPrimitive));
+    rv = aTransferable->GetTransferData(kFilePromiseDirectoryMime,
+                                        getter_AddRefs(dirPrimitive));
+    NS_ENSURE_SUCCESS(rv, rv);
     nsCOMPtr<nsIFile> destDirectory = do_QueryInterface(dirPrimitive);
     if (!destDirectory)
       return NS_ERROR_FAILURE;

dom/base/nsContentUtils.cpp

@@ -8110,7 +8110,10 @@ nsContentUtils::TransferableToIPCTransferable(nsITransferable* aTransferable,
       }
 
       nsCOMPtr<nsISupports> data;
-      aTransferable->GetTransferData(flavorStr.get(), getter_AddRefs(data));
+      if (NS_FAILED(aTransferable->GetTransferData(flavorStr.get(),
+                                                   getter_AddRefs(data)))) {
+        continue;
+      }
 
       nsCOMPtr<nsISupportsString> text = do_QueryInterface(data);
       nsCOMPtr<nsISupportsCString> ctext = do_QueryInterface(data);

editor/libeditor/HTMLEditorDataTransfer.cpp

@@ -1595,8 +1595,11 @@ HTMLEditor::PasteInternal(int32_t aClipboardType,
     contextTransferable->Init(nullptr);
     contextTransferable->AddDataFlavor(kHTMLContext);
     clipboard->GetData(contextTransferable, aClipboardType);
-    contextTransferable->GetTransferData(kHTMLContext,
-                                         getter_AddRefs(contextDataObj));
+    rv = contextTransferable->GetTransferData(kHTMLContext,
+                                              getter_AddRefs(contextDataObj));
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
 
     nsCOMPtr<nsITransferable> infoTransferable =
       do_CreateInstance("@mozilla.org/widget/transferable;1");
@@ -1606,8 +1609,11 @@ HTMLEditor::PasteInternal(int32_t aClipboardType,
     infoTransferable->Init(nullptr);
     infoTransferable->AddDataFlavor(kHTMLInfo);
     clipboard->GetData(infoTransferable, aClipboardType);
-    infoTransferable->GetTransferData(kHTMLInfo,
-                                      getter_AddRefs(infoDataObj));
+    rv = infoTransferable->GetTransferData(kHTMLInfo,
+                                           getter_AddRefs(infoDataObj));
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
 
     if (contextDataObj) {
       textDataObj = do_QueryInterface(contextDataObj);

widget/cocoa/nsChildView.mm

@@ -6,6 +6,7 @@
 #include "mozilla/ArrayUtils.h"
 
 #include "mozilla/Logging.h"
+#include "mozilla/Unused.h"
 
 #include <unistd.h>
 #include <math.h>
@@ -6256,8 +6257,8 @@ provideDataForType:(NSString*)aType
           // Now request the kFilePromiseMime data, which will invoke the data
           // provider. If successful, the file will have been created.
           nsCOMPtr<nsISupports> fileDataPrimitive;
-          item->GetTransferData(kFilePromiseMime,
-                                getter_AddRefs(fileDataPrimitive));
+          Unused << item->GetTransferData(kFilePromiseMime,
+                                          getter_AddRefs(fileDataPrimitive));
         }
         CFRelease(urlRef);
         CFRelease(pboardRef);

widget/cocoa/nsClipboard.mm

@@ -562,7 +562,10 @@ nsClipboard::PasteboardDictFromTransferable(nsITransferable* aTransferable)
              flavorStr.EqualsLiteral(kJPGImageMime) || flavorStr.EqualsLiteral(kGIFImageMime) ||
              flavorStr.EqualsLiteral(kNativeImageMime)) {
       nsCOMPtr<nsISupports> transferSupports;
-      aTransferable->GetTransferData(flavorStr.get(), getter_AddRefs(transferSupports));
+      rv = aTransferable->GetTransferData(flavorStr.get(), getter_AddRefs(transferSupports));
+      if (NS_FAILED(rv)) {
+        continue;
+      }
 
       nsCOMPtr<imgIContainer> image(do_QueryInterface(transferSupports));
       if (!image) {

widget/gtk/nsClipboard.cpp

@@ -482,8 +482,9 @@ nsClipboard::SelectionGetEvent(GtkClipboard     *aClipboard,
         // the transferable for this clipboard and try to get the
         // text/unicode type for it.
         rv = trans->GetTransferData("text/unicode", getter_AddRefs(item));
-        if (!item || NS_FAILED(rv))
+        if (NS_FAILED(rv) || !item) {
             return;
+        }
 
         nsCOMPtr<nsISupportsString> wideString;
         wideString = do_QueryInterface(item);
@@ -533,7 +534,7 @@ nsClipboard::SelectionGetEvent(GtkClipboard     *aClipboard,
 
     if (selectionTarget == gdk_atom_intern(kHTMLMime, FALSE)) {
         rv = trans->GetTransferData(kHTMLMime, getter_AddRefs(item));
-        if (!item || NS_FAILED(rv)) {
+        if (NS_FAILED(rv) || !item) {
             return;
         }
 
@@ -564,7 +565,7 @@ nsClipboard::SelectionGetEvent(GtkClipboard     *aClipboard,
 
     rv = trans->GetTransferData(target_name, getter_AddRefs(item));
     // nothing found?
-    if (!item || NS_FAILED(rv)) {
+    if (NS_FAILED(rv) || !item) {
         g_free(target_name);
         return;
     }

widget/gtk/nsDragService.cpp

@@ -1739,11 +1739,16 @@ nsDragService::SourceBeginDrag(GdkDragContext *aContext)
     for (uint32_t i = 0; i < flavors.Length(); ++i) {
         if (flavors[i].EqualsLiteral(kFilePromiseDestFilename)) {
             nsCOMPtr<nsISupports> data;
-            transferable->GetTransferData(kFilePromiseDestFilename,
-                                          getter_AddRefs(data));
-            nsCOMPtr<nsISupportsString> fileName = do_QueryInterface(data);
-            if (!fileName)
+            rv  = transferable->GetTransferData(kFilePromiseDestFilename,
+                                                getter_AddRefs(data));
+            if (NS_FAILED(rv)) {
                 return;
+            }
+
+            nsCOMPtr<nsISupportsString> fileName = do_QueryInterface(data);
+            if (!fileName) {
+                return;
+            }
 
             nsAutoString fileNameStr;
             fileName->GetData(fileNameStr);

widget/nsITransferable.idl

@@ -131,7 +131,7 @@ interface nsITransferable : nsISupports
     * @param  aData the data. Some variant of class in nsISupportsPrimitives.idl
     * @param  aDataLen the length of the data
     */
-  void getTransferData(in string aFlavor, out nsISupports aData);
+  [must_use] void getTransferData(in string aFlavor, out nsISupports aData);
 
   /**
     * Returns the best flavor in the transferable, given those that have

widget/windows/nsDataObj.cpp

@@ -897,65 +897,67 @@ nsDataObj::GetDib(const nsACString& inFlavor,
                   FORMATETC &aFormat,
                   STGMEDIUM & aSTG)
 {
-  ULONG result = E_FAIL;
   nsCOMPtr<nsISupports> genericDataWrapper;
-  mTransferable->GetTransferData(PromiseFlatCString(inFlavor).get(), getter_AddRefs(genericDataWrapper));
-  nsCOMPtr<imgIContainer> image ( do_QueryInterface(genericDataWrapper) );
-  if ( image ) {
-    nsCOMPtr<imgITools> imgTools = do_CreateInstance("@mozilla.org/image/tools;1");
-
-    nsAutoString options;
-    if (aFormat.cfFormat == CF_DIBV5) {
-      options.AppendLiteral("version=5");
-    } else {
-      options.AppendLiteral("version=3");
-    }
-
-    nsCOMPtr<nsIInputStream> inputStream;
-    nsresult rv = imgTools->EncodeImage(image, NS_LITERAL_CSTRING(IMAGE_BMP),
-                                        options, getter_AddRefs(inputStream));
-    if (NS_FAILED(rv) || !inputStream) {
-      return E_FAIL;
-    }
-
-    nsCOMPtr<imgIEncoder> encoder = do_QueryInterface(inputStream);
-    if (!encoder) {
-      return E_FAIL;
-    }
-
-    uint32_t size = 0;
-    rv = encoder->GetImageBufferUsed(&size);
-    if (NS_FAILED(rv) || size <= BFH_LENGTH) {
-      return E_FAIL;
-    }
-
-    char *src = nullptr;
-    rv = encoder->GetImageBuffer(&src);
-    if (NS_FAILED(rv) || !src) {
-      return E_FAIL;
-    }
-
-    // We don't want the file header.
-    src += BFH_LENGTH;
-    size -= BFH_LENGTH;
-
-    HGLOBAL glob = ::GlobalAlloc(GMEM_MOVEABLE | GMEM_ZEROINIT, size);
-    if (!glob) {
-      DWORD err = ::GetLastError();
-      return E_FAIL;
-    }
-
-    char *dst = (char*) ::GlobalLock(glob);
-    ::CopyMemory(dst, src, size);
-    ::GlobalUnlock(glob);
-
-    aSTG.hGlobal = glob;
-    aSTG.tymed = TYMED_HGLOBAL;
-    result = S_OK;
-  } else {
-    NS_WARNING ( "Definitely not an image on clipboard" );
+  if (NS_FAILED(mTransferable->GetTransferData(PromiseFlatCString(inFlavor).get(),
+                                               getter_AddRefs(genericDataWrapper)))) {
+    return E_FAIL;
   }
-  return result;
+
+  nsCOMPtr<imgIContainer> image = do_QueryInterface(genericDataWrapper);
+  if (!image) {
+    return E_FAIL;
+  }
+
+  nsCOMPtr<imgITools> imgTools = do_CreateInstance("@mozilla.org/image/tools;1");
+
+  nsAutoString options;
+  if (aFormat.cfFormat == CF_DIBV5) {
+    options.AppendLiteral("version=5");
+  } else {
+    options.AppendLiteral("version=3");
+  }
+
+  nsCOMPtr<nsIInputStream> inputStream;
+  nsresult rv = imgTools->EncodeImage(image, NS_LITERAL_CSTRING(IMAGE_BMP),
+                                      options, getter_AddRefs(inputStream));
+  if (NS_FAILED(rv) || !inputStream) {
+    return E_FAIL;
+  }
+
+  nsCOMPtr<imgIEncoder> encoder = do_QueryInterface(inputStream);
+  if (!encoder) {
+    return E_FAIL;
+  }
+
+  uint32_t size = 0;
+  rv = encoder->GetImageBufferUsed(&size);
+  if (NS_FAILED(rv) || size <= BFH_LENGTH) {
+    return E_FAIL;
+  }
+
+  char *src = nullptr;
+  rv = encoder->GetImageBuffer(&src);
+  if (NS_FAILED(rv) || !src) {
+    return E_FAIL;
+  }
+
+  // We don't want the file header.
+  src += BFH_LENGTH;
+  size -= BFH_LENGTH;
+
+  HGLOBAL glob = ::GlobalAlloc(GMEM_MOVEABLE | GMEM_ZEROINIT, size);
+  if (!glob) {
+    DWORD err = ::GetLastError();
+    return E_FAIL;
+  }
+
+  char *dst = (char*) ::GlobalLock(glob);
+  ::CopyMemory(dst, src, size);
+  ::GlobalUnlock(glob);
+
+  aSTG.hGlobal = glob;
+  aSTG.tymed = TYMED_HGLOBAL;
+  return S_OK;
 }
 
 
@@ -1374,9 +1376,11 @@ HRESULT nsDataObj::GetText(const nsACString & aDataFlavor, FORMATETC& aFE, STGME
 
   // NOTE: CreateDataFromPrimitive creates new memory, that needs to be deleted
   nsCOMPtr<nsISupports> genericDataWrapper;
-  mTransferable->GetTransferData(flavorStr, getter_AddRefs(genericDataWrapper));
-  if ( !genericDataWrapper )
+  nsresult rv = mTransferable->GetTransferData(flavorStr,
+                                               getter_AddRefs(genericDataWrapper));
+  if (NS_FAILED(rv) || !genericDataWrapper) {
     return E_FAIL;
+  }
 
   uint32_t   len;
   nsPrimitiveHelpers::CreateDataFromPrimitive(
@@ -1484,7 +1488,9 @@ HRESULT nsDataObj::DropFile(FORMATETC& aFE, STGMEDIUM& aSTG)
   nsresult rv;
   nsCOMPtr<nsISupports> genericDataWrapper;
 
-  mTransferable->GetTransferData(kFileMime, getter_AddRefs(genericDataWrapper));
+  if (NS_FAILED(mTransferable->GetTransferData(kFileMime, getter_AddRefs(genericDataWrapper)))) {
+    return E_FAIL;
+  }
   nsCOMPtr<nsIFile> file ( do_QueryInterface(genericDataWrapper) );
   if (!file)
     return E_FAIL;
@@ -1537,7 +1543,10 @@ HRESULT nsDataObj::DropImage(FORMATETC& aFE, STGMEDIUM& aSTG)
   if (!mCachedTempFile) {
     nsCOMPtr<nsISupports> genericDataWrapper;
 
-    mTransferable->GetTransferData(kNativeImageMime, getter_AddRefs(genericDataWrapper));
+    if (NS_FAILED(mTransferable->GetTransferData(kNativeImageMime,
+                                                 getter_AddRefs(genericDataWrapper)))) {
+      return E_FAIL;
+    }
     nsCOMPtr<imgIContainer> image(do_QueryInterface(genericDataWrapper));
     if (!image) 
       return E_FAIL;
@@ -2096,7 +2105,8 @@ HRESULT nsDataObj::GetDownloadDetails(nsIURI **aSourceURI,
 
   // get the URI from the kFilePromiseURLMime flavor
   nsCOMPtr<nsISupports> urlPrimitive;
-  mTransferable->GetTransferData(kFilePromiseURLMime, getter_AddRefs(urlPrimitive));
+  nsresult rv = mTransferable->GetTransferData(kFilePromiseURLMime, getter_AddRefs(urlPrimitive));
+  NS_ENSURE_SUCCESS(rv, E_FAIL);
   nsCOMPtr<nsISupportsString> srcUrlPrimitive = do_QueryInterface(urlPrimitive);
   NS_ENSURE_TRUE(srcUrlPrimitive, E_FAIL);
   
@@ -2109,7 +2119,8 @@ HRESULT nsDataObj::GetDownloadDetails(nsIURI **aSourceURI,
 
   nsAutoString srcFileName;
   nsCOMPtr<nsISupports> fileNamePrimitive;
-  mTransferable->GetTransferData(kFilePromiseDestFilename, getter_AddRefs(fileNamePrimitive));
+  rv = mTransferable->GetTransferData(kFilePromiseDestFilename, getter_AddRefs(fileNamePrimitive));
+  NS_ENSURE_SUCCESS(rv, E_FAIL);
   nsCOMPtr<nsISupportsString> srcFileNamePrimitive = do_QueryInterface(fileNamePrimitive);
   if (srcFileNamePrimitive) {
     srcFileNamePrimitive->GetData(srcFileName);