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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-

  *

  * 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/. */

 #if defined(MOZ_WIDGET_GTK)

 #include <gtk/gtk.h>

 #include <gdk/gdkx.h>

 #elif defined(MOZ_WIDGET_QT)

 #include <QWindow>

 #endif

 #include "nsShmImage.h"

 #include "gfxPlatform.h"

 #include "gfxImageSurface.h"

 #ifdef MOZ_HAVE_SHMIMAGE

 using namespace mozilla::ipc;

 // If XShm isn't available to our client, we'll try XShm once, fail,

 // set this to false and then never try again.

 static bool gShmAvailable = true;

 bool nsShmImage::UseShm()

 {

     return gfxPlatform::GetPlatform()->

         ScreenReferenceSurface()->GetType() == gfxSurfaceType::Image

         && gShmAvailable;

 }

 already_AddRefed<nsShmImage>

 nsShmImage::Create(const gfxIntSize& aSize,

                    Visual* aVisual, unsigned int aDepth)

 {

     Display* dpy = DISPLAY();

     nsRefPtr<nsShmImage> shm = new nsShmImage();

     shm->mImage = XShmCreateImage(dpy, aVisual, aDepth,

                                   ZPixmap, nullptr,

                                   &(shm->mInfo),

                                   aSize.width, aSize.height);

     if (!shm->mImage) {

         return nullptr;

     }

     size_t size = SharedMemory::PageAlignedSize(

         shm->mImage->bytes_per_line * shm->mImage->height);

     shm->mSegment = new SharedMemorySysV();

     if (!shm->mSegment->Create(size) || !shm->mSegment->Map(size)) {

         return nullptr;

     }

     shm->mInfo.shmid = shm->mSegment->GetHandle();

     shm->mInfo.shmaddr =

         shm->mImage->data = static_cast<char*>(shm->mSegment->memory());

     shm->mInfo.readOnly = False;

     int xerror = 0;

 #if defined(MOZ_WIDGET_GTK)

     gdk_error_trap_push();

     Status attachOk = XShmAttach(dpy, &shm->mInfo);

     XSync(dpy, False);

     xerror = gdk_error_trap_pop();

 #elif defined(MOZ_WIDGET_QT)

     Status attachOk = XShmAttach(dpy, &shm->mInfo);

 #endif

     if (!attachOk || xerror) {

         // Assume XShm isn't available, and don't attempt to use it

         // again.

         gShmAvailable = false;

         return nullptr;

     }

     shm->mXAttached = true;

     shm->mSize = aSize;

     switch (shm->mImage->depth) {

     case 32:

         if ((shm->mImage->red_mask == 0xff0000) &&

             (shm->mImage->green_mask == 0xff00) &&

             (shm->mImage->blue_mask == 0xff)) {

             shm->mFormat = gfxImageFormat::ARGB32;

             break;

         }

         goto unsupported;

     case 24:

         // Only xRGB is supported.

         if ((shm->mImage->red_mask == 0xff0000) &&

             (shm->mImage->green_mask == 0xff00) &&

             (shm->mImage->blue_mask == 0xff)) {

             shm->mFormat = gfxImageFormat::RGB24;

             break;

         }

         goto unsupported;

     case 16:

         shm->mFormat = gfxImageFormat::RGB16_565; break;

     unsupported:

     default:

         NS_WARNING("Unsupported XShm Image format!");

         gShmAvailable = false;

         return nullptr;

     }

     return shm.forget();

 }

 already_AddRefed<gfxASurface>

 nsShmImage::AsSurface()

 {

     return nsRefPtr<gfxASurface>(

         new gfxImageSurface(static_cast<unsigned char*>(mSegment->memory()),

                             mSize,

                             mImage->bytes_per_line,

                             mFormat)

         ).forget();

 }

 #if (MOZ_WIDGET_GTK == 2)

 void

 nsShmImage::Put(GdkWindow* aWindow, GdkRectangle* aRects, GdkRectangle* aEnd)

 {

     GdkDrawable* gd;

     gint dx, dy;

     gdk_window_get_internal_paint_info(aWindow, &gd, &dx, &dy);

     Display* dpy = gdk_x11_get_default_xdisplay();

     Drawable d = GDK_DRAWABLE_XID(gd);

     GC gc = XCreateGC(dpy, d, 0, nullptr);

     for (GdkRectangle* r = aRects; r < aEnd; r++) {

         XShmPutImage(dpy, d, gc, mImage,

                      r->x, r->y,

                      r->x - dx, r->y - dy,

                      r->width, r->height,

                      False);

     }

     XFreeGC(dpy, gc);

     // FIXME/bug 597336: we need to ensure that the shm image isn't

     // scribbled over before all its pending XShmPutImage()s complete.

     // However, XSync() is an unnecessarily heavyweight

     // synchronization mechanism; other options are possible.  If this

     // XSync is shown to hurt responsiveness, we need to explore the

     // other options.

     XSync(dpy, False);

 }

 #elif (MOZ_WIDGET_GTK == 3)

 void

 nsShmImage::Put(GdkWindow* aWindow, cairo_rectangle_list_t* aRects)

 {

     Display* dpy = gdk_x11_get_default_xdisplay();

     Drawable d = GDK_WINDOW_XID(aWindow);

     int dx = 0, dy = 0;

     GC gc = XCreateGC(dpy, d, 0, nullptr);

     cairo_rectangle_t r;

     for (int i = 0; i < aRects->num_rectangles; i++) {

         r = aRects->rectangles[i];

         XShmPutImage(dpy, d, gc, mImage,

                      r.x, r.y,

                      r.x - dx, r.y - dy,

                      r.width, r.height,

                      False);

     }

     XFreeGC(dpy, gc);

     // FIXME/bug 597336: we need to ensure that the shm image isn't

     // scribbled over before all its pending XShmPutImage()s complete.

     // However, XSync() is an unnecessarily heavyweight

     // synchronization mechanism; other options are possible.  If this

     // XSync is shown to hurt responsiveness, we need to explore the

     // other options.

     XSync(dpy, False);

 }

 #elif defined(MOZ_WIDGET_QT)

 void

 nsShmImage::Put(QWindow* aWindow, QRect& aRect)

 {

     Display* dpy = gfxQtPlatform::GetXDisplay(aWindow);

     Drawable d = aWindow->winId();

     GC gc = XCreateGC(dpy, d, 0, nullptr);

     // Avoid out of bounds painting

     QRect inter = aRect.intersected(aWindow->geometry());

     XShmPutImage(dpy, d, gc, mImage,

                  inter.x(), inter.y(),

                  inter.x(), inter.y(),

                  inter.width(), inter.height(),

                  False);

     XFreeGC(dpy, gc);

 }

 #endif

 already_AddRefed<gfxASurface>

 nsShmImage::EnsureShmImage(const gfxIntSize& aSize, Visual* aVisual, unsigned int aDepth,

                nsRefPtr<nsShmImage>& aImage)

 {

     if (!aImage || aImage->Size() != aSize) {

         // Because we XSync() after XShmAttach() to trap errors, we

         // know that the X server has the old image's memory mapped

         // into its address space, so it's OK to destroy the old image

         // here even if there are outstanding Puts.  The Detach is

         // ordered after the Puts.

         aImage = nsShmImage::Create(aSize, aVisual, aDepth);

     }

     return !aImage ? nullptr : aImage->AsSurface();

 }

 #endif  // defined(MOZ_X11) && defined(MOZ_HAVE_SHAREDMEMORYSYSV)