gecko-dev/widget/nsShmImage.cpp

199 lines
5.9 KiB
C++

/* -*- 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"
#ifdef MOZ_WIDGET_GTK
#include "gfxPlatformGtk.h"
#endif
#ifdef MOZ_HAVE_SHMIMAGE
using namespace mozilla::ipc;
using namespace mozilla::gfx;
// 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()
{
#ifdef MOZ_WIDGET_GTK
return (gShmAvailable && !gfxPlatformGtk::GetPlatform()->UseXRender());
#else
return gShmAvailable;
#endif
}
#ifdef MOZ_WIDGET_GTK
static int gShmError = 0;
static int
TrapShmError(Display* aDisplay, XErrorEvent* aEvent)
{
// store the error code and ignore the error
gShmError = aEvent->error_code;
return 0;
}
#endif
already_AddRefed<nsShmImage>
nsShmImage::Create(const gfxIntSize& aSize,
Display* aDisplay, Visual* aVisual, unsigned int aDepth)
{
nsRefPtr<nsShmImage> shm = new nsShmImage();
shm->mDisplay = aDisplay;
shm->mImage = XShmCreateImage(aDisplay, 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;
#if defined(MOZ_WIDGET_GTK)
gShmError = 0;
XErrorHandler previousHandler = XSetErrorHandler(TrapShmError);
Status attachOk = XShmAttach(aDisplay, &shm->mInfo);
XSync(aDisplay, False);
XSetErrorHandler(previousHandler);
if (gShmError) {
attachOk = 0;
}
#elif defined(MOZ_WIDGET_QT)
Status attachOk = XShmAttach(aDisplay, &shm->mInfo);
#endif
if (!attachOk) {
// 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 = SurfaceFormat::B8G8R8A8;
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 = SurfaceFormat::B8G8R8X8;
break;
}
goto unsupported;
case 16:
shm->mFormat = SurfaceFormat::R5G6B5;
break;
unsupported:
default:
NS_WARNING("Unsupported XShm Image format!");
gShmAvailable = false;
return nullptr;
}
return shm.forget();
}
already_AddRefed<DrawTarget>
nsShmImage::CreateDrawTarget()
{
return gfxPlatform::GetPlatform()->CreateDrawTargetForData(
static_cast<unsigned char*>(mSegment->memory()),
mSize,
mImage->bytes_per_line,
mFormat);
}
#ifdef MOZ_WIDGET_GTK
void
nsShmImage::Put(Display* aDisplay, Drawable aWindow, const nsIntRegion& aRegion)
{
GC gc = XCreateGC(aDisplay, aWindow, 0, nullptr);
nsIntRegion bounded;
bounded.And(aRegion, nsIntRect(0, 0, mImage->width, mImage->height));
nsIntRegionRectIterator iter(bounded);
for (const nsIntRect *r = iter.Next(); r; r = iter.Next()) {
XShmPutImage(aDisplay, aWindow, gc, mImage,
r->x, r->y,
r->x, r->y,
r->width, r->height,
False);
}
XFreeGC(aDisplay, 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(aDisplay, 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<DrawTarget>
nsShmImage::EnsureShmImage(const gfxIntSize& aSize,
Display* aDisplay, 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, aDisplay, aVisual, aDepth);
}
return !aImage ? nullptr : aImage->CreateDrawTarget();
}
#endif // defined(MOZ_X11) && defined(MOZ_HAVE_SHAREDMEMORYSYSV)