1 files changed, 81 insertions, 0 deletions
diff --git a/gfx/src/X11Util.cpp b/gfx/src/X11Util.cpp
new file mode 100644
index 0000000000..709d652bae
--- /dev/null
+++ b/gfx/src/X11Util.cpp
@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "X11Util.h"
+#include "nsDebug.h"          // for NS_ASSERTION, etc
+#include "MainThreadUtils.h"  // for NS_IsMainThread
+
+namespace mozilla {
+
+void FindVisualAndDepth(Display* aDisplay, VisualID aVisualID, Visual** aVisual,
+                        int* aDepth) {
+  const Screen* screen = DefaultScreenOfDisplay(aDisplay);
+
+  for (int d = 0; d < screen->ndepths; d++) {
+    Depth* d_info = &screen->depths[d];
+    for (int v = 0; v < d_info->nvisuals; v++) {
+      Visual* visual = &d_info->visuals[v];
+      if (visual->visualid == aVisualID) {
+        *aVisual = visual;
+        *aDepth = d_info->depth;
+        return;
+      }
+    }
+  }
+
+  NS_ASSERTION(aVisualID == X11None, "VisualID not on Screen.");
+  *aVisual = nullptr;
+  *aDepth = 0;
+}
+
+void FinishX(Display* aDisplay) {
+  unsigned long lastRequest = NextRequest(aDisplay) - 1;
+  if (lastRequest == LastKnownRequestProcessed(aDisplay)) return;
+
+  XSync(aDisplay, X11False);
+}
+
+ScopedXErrorHandler::ErrorEvent* ScopedXErrorHandler::sXErrorPtr;
+
+int ScopedXErrorHandler::ErrorHandler(Display*, XErrorEvent* ev) {
+  // only record the error if no error was previously recorded.
+  // this means that in case of multiple errors, it's the first error that we
+  // report.
+  if (!sXErrorPtr->mError.error_code) sXErrorPtr->mError = *ev;
+  return 0;
+}
+
+ScopedXErrorHandler::ScopedXErrorHandler(bool aAllowOffMainThread) {
+  if (!aAllowOffMainThread) {
+    // Off main thread usage is not safe in general, but OMTC GL layers uses
+    // this with the main thread blocked, which makes it safe.
+    NS_WARNING_ASSERTION(
+        NS_IsMainThread(),
+        "ScopedXErrorHandler being called off main thread, may cause issues");
+  }
+  // let sXErrorPtr point to this object's mXError object, but don't reset this
+  // mXError object! think of the case of nested ScopedXErrorHandler's.
+  mOldXErrorPtr = sXErrorPtr;
+  sXErrorPtr = &mXError;
+  mOldErrorHandler = XSetErrorHandler(ErrorHandler);
+}
+
+ScopedXErrorHandler::~ScopedXErrorHandler() {
+  sXErrorPtr = mOldXErrorPtr;
+  XSetErrorHandler(mOldErrorHandler);
+}
+
+bool ScopedXErrorHandler::SyncAndGetError(Display* dpy, XErrorEvent* ev) {
+  FinishX(dpy);
+
+  bool retval = mXError.mError.error_code != 0;
+  if (ev) *ev = mXError.mError;
+  mXError = ErrorEvent();  // reset
+  return retval;
+}
+
+}  // namespace mozilla