Bug 426177 - Alert user when selecting unreadable input file r=emilio

The change is done at the nsFilePicker level, when it's in open mode.

Differential Revision: https://phabricator.services.mozilla.com/D166419

toolkit/locales/en-US/chrome/global/filepicker.properties

@@ -15,3 +15,4 @@ audioTitle=Audio Files
 videoTitle=Video Files
 
 formatLabel=Format:
+selectedFileNotReadableError=Selected file does not have read permission

widget/gtk/nsFilePicker.cpp

@@ -16,6 +16,8 @@
 #include "nsIURI.h"
 #include "nsIWidget.h"
 #include "nsIFile.h"
+#include "nsIStringBundle.h"
+#include "mozilla/Components.h"
 #include "mozilla/Preferences.h"
 
 #include "nsArrayEnumerator.h"
@@ -511,6 +513,50 @@ void nsFilePicker::OnDestroy(GtkWidget* file_chooser, gpointer user_data) {
                                               GTK_RESPONSE_CANCEL);
 }
 
+bool nsFilePicker::WarnForNonReadableFile(void* file_chooser) {
+  nsCOMPtr<nsIFile> file;
+  GetFile(getter_AddRefs(file));
+  if (!file) {
+    return false;
+  }
+
+  bool isReadable = false;
+  file->IsReadable(&isReadable);
+  if (isReadable) {
+    return false;
+  }
+
+  nsCOMPtr<nsIStringBundleService> stringService =
+      mozilla::components::StringBundle::Service();
+  if (!stringService) {
+    return false;
+  }
+
+  nsCOMPtr<nsIStringBundle> filepickerBundle;
+  nsresult rv = stringService->CreateBundle(
+      "chrome://global/locale/filepicker.properties",
+      getter_AddRefs(filepickerBundle));
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  nsAutoString errorMessage;
+  rv = filepickerBundle->GetStringFromName("selectedFileNotReadableError",
+                                           errorMessage);
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  GtkDialogFlags flags = GTK_DIALOG_DESTROY_WITH_PARENT;
+  auto* cancel_dialog = gtk_message_dialog_new(
+      GTK_WINDOW(file_chooser), flags, GTK_MESSAGE_ERROR, GTK_BUTTONS_CLOSE,
+      "%s", NS_ConvertUTF16toUTF8(errorMessage).get());
+  gtk_dialog_run(GTK_DIALOG(cancel_dialog));
+  gtk_widget_destroy(cancel_dialog);
+
+  return true;
+}
+
 void nsFilePicker::Done(void* file_chooser, gint response) {
   mRunning = false;
 
@@ -528,6 +574,10 @@ void nsFilePicker::Done(void* file_chooser, gint response) {
           file->Exists(&exists);
           if (exists) result = nsIFilePicker::returnReplace;
         }
+      } else if (mMode == nsIFilePicker::modeOpen) {
+        if (WarnForNonReadableFile(file_chooser)) {
+          result = nsIFilePicker::returnCancel;
+        }
       }
       break;
 

widget/gtk/nsFilePicker.h

@@ -48,6 +48,8 @@ class nsFilePicker : public nsBaseFilePicker {
   nsresult Show(int16_t* aReturn) override;
   void ReadValuesFromFileChooser(void* file_chooser);
 
+  bool WarnForNonReadableFile(void* file_chooser);
+
   static void OnResponse(void* file_chooser, gint response_id,
                          gpointer user_data);
   static void OnDestroy(GtkWidget* file_chooser, gpointer user_data);