/* -*- 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, False);

}

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