widget/nsShmImage.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #if defined(MOZ_WIDGET_GTK)
   8 #include <gtk/gtk.h>
   9 #include <gdk/gdkx.h>
  10 #elif defined(MOZ_WIDGET_QT)
  11 #include <QWindow>
  12 #endif
  13
  14 #include "nsShmImage.h"
  15 #ifdef MOZ_WIDGET_GTK
  16 #include "gfxPlatformGtk.h"
  17 #endif
  18 #include "gfxImageSurface.h"
  19
  20 #ifdef MOZ_HAVE_SHMIMAGE
  21
  22 using namespace mozilla::ipc;
  23
  24 // If XShm isn't available to our client, we'll try XShm once, fail,
  25 // set this to false and then never try again.
  26 static bool gShmAvailable = true;
  27 bool nsShmImage::UseShm()
  28 {
  29 #ifdef MOZ_WIDGET_GTK
  30     return (gShmAvailable && !gfxPlatformGtk::GetPlatform()->UseXRender());
  31 #else
  32     return gShmAvailable;
  33 #endif
  34 }
  35
  36 already_AddRefed<nsShmImage>
  37 nsShmImage::Create(const gfxIntSize& aSize,
  38                    Visual* aVisual, unsigned int aDepth)
  39 {
  40     Display* dpy = DISPLAY();
  41
  42     nsRefPtr<nsShmImage> shm = new nsShmImage();
  43     shm->mImage = XShmCreateImage(dpy, aVisual, aDepth,
  44                                   ZPixmap, nullptr,
  45                                   &(shm->mInfo),
  46                                   aSize.width, aSize.height);
  47     if (!shm->mImage) {
  48         return nullptr;
  49     }
  50
  51     size_t size = SharedMemory::PageAlignedSize(
  52         shm->mImage->bytes_per_line * shm->mImage->height);
  53     shm->mSegment = new SharedMemorySysV();
  54     if (!shm->mSegment->Create(size) || !shm->mSegment->Map(size)) {
  55         return nullptr;
  56     }
  57
  58     shm->mInfo.shmid = shm->mSegment->GetHandle();
  59     shm->mInfo.shmaddr =
  60         shm->mImage->data = static_cast<char*>(shm->mSegment->memory());
  61     shm->mInfo.readOnly = False;
  62
  63     int xerror = 0;
  64 #if defined(MOZ_WIDGET_GTK)
  65     gdk_error_trap_push();
  66     Status attachOk = XShmAttach(dpy, &shm->mInfo);
  67     XSync(dpy, False);
  68     xerror = gdk_error_trap_pop();
  69 #elif defined(MOZ_WIDGET_QT)
  70     Status attachOk = XShmAttach(dpy, &shm->mInfo);
  71 #endif
  72
  73     if (!attachOk || xerror) {
  74         // Assume XShm isn't available, and don't attempt to use it
  75         // again.
  76         gShmAvailable = false;
  77         return nullptr;
  78     }
  79
  80     shm->mXAttached = true;
  81     shm->mSize = aSize;
  82     switch (shm->mImage->depth) {
  83     case 32:
  84         if ((shm->mImage->red_mask == 0xff0000) &&
  85             (shm->mImage->green_mask == 0xff00) &&
  86             (shm->mImage->blue_mask == 0xff)) {
  87             shm->mFormat = gfxImageFormat::ARGB32;
  88             break;
  89         }
  90         goto unsupported;
  91     case 24:
  92         // Only xRGB is supported.
  93         if ((shm->mImage->red_mask == 0xff0000) &&
  94             (shm->mImage->green_mask == 0xff00) &&
  95             (shm->mImage->blue_mask == 0xff)) {
  96             shm->mFormat = gfxImageFormat::RGB24;
  97             break;
  98         }
  99         goto unsupported;
 100     case 16:
 101         shm->mFormat = gfxImageFormat::RGB16_565; break;
 102     unsupported:
 103     default:
 104         NS_WARNING("Unsupported XShm Image format!");
 105         gShmAvailable = false;
 106         return nullptr;
 107     }
 108     return shm.forget();
 109 }
 110
 111 already_AddRefed<gfxASurface>
 112 nsShmImage::AsSurface()
 113 {
 114     return nsRefPtr<gfxASurface>(
 115         new gfxImageSurface(static_cast<unsigned char*>(mSegment->memory()),
 116                             mSize,
 117                             mImage->bytes_per_line,
 118                             mFormat)
 119         ).forget();
 120 }
 121
 122 #if (MOZ_WIDGET_GTK == 2)
 123 void
 124 nsShmImage::Put(GdkWindow* aWindow, GdkRectangle* aRects, GdkRectangle* aEnd)
 125 {
 126     GdkDrawable* gd;
 127     gint dx, dy;
 128     gdk_window_get_internal_paint_info(aWindow, &gd, &dx, &dy);
 129
 130     Display* dpy = gdk_x11_get_default_xdisplay();
 131     Drawable d = GDK_DRAWABLE_XID(gd);
 132
 133     GC gc = XCreateGC(dpy, d, 0, nullptr);
 134     for (GdkRectangle* r = aRects; r < aEnd; r++) {
 135         XShmPutImage(dpy, d, gc, mImage,
 136                      r->x, r->y,
 137                      r->x - dx, r->y - dy,
 138                      r->width, r->height,
 139                      False);
 140     }
 141     XFreeGC(dpy, gc);
 142
 143     // FIXME/bug 597336: we need to ensure that the shm image isn't
 144     // scribbled over before all its pending XShmPutImage()s complete.
 145     // However, XSync() is an unnecessarily heavyweight
 146     // synchronization mechanism; other options are possible.  If this
 147     // XSync is shown to hurt responsiveness, we need to explore the
 148     // other options.
 149     XSync(dpy, False);
 150 }
 151
 152 #elif (MOZ_WIDGET_GTK == 3)
 153 void
 154 nsShmImage::Put(GdkWindow* aWindow, cairo_rectangle_list_t* aRects)
 155 {
 156     Display* dpy = gdk_x11_get_default_xdisplay();
 157     Drawable d = GDK_WINDOW_XID(aWindow);
 158     int dx = 0, dy = 0;
 159
 160     GC gc = XCreateGC(dpy, d, 0, nullptr);
 161     cairo_rectangle_t r;
 162     for (int i = 0; i < aRects->num_rectangles; i++) {
 163         r = aRects->rectangles[i];
 164         XShmPutImage(dpy, d, gc, mImage,
 165                      r.x, r.y,
 166                      r.x - dx, r.y - dy,
 167                      r.width, r.height,
 168                      False);
 169     }
 170
 171     XFreeGC(dpy, gc);
 172
 173     // FIXME/bug 597336: we need to ensure that the shm image isn't
 174     // scribbled over before all its pending XShmPutImage()s complete.
 175     // However, XSync() is an unnecessarily heavyweight
 176     // synchronization mechanism; other options are possible.  If this
 177     // XSync is shown to hurt responsiveness, we need to explore the
 178     // other options.
 179     XSync(dpy, False);
 180 }
 181
 182 #elif defined(MOZ_WIDGET_QT)
 183 void
 184 nsShmImage::Put(QWindow* aWindow, QRect& aRect)
 185 {
 186     Display* dpy = gfxQtPlatform::GetXDisplay(aWindow);
 187     Drawable d = aWindow->winId();
 188
 189     GC gc = XCreateGC(dpy, d, 0, nullptr);
 190     // Avoid out of bounds painting
 191     QRect inter = aRect.intersected(aWindow->geometry());
 192     XShmPutImage(dpy, d, gc, mImage,
 193                  inter.x(), inter.y(),
 194                  inter.x(), inter.y(),
 195                  inter.width(), inter.height(),
 196                  False);
 197     XFreeGC(dpy, gc);
 198 }
 199 #endif
 200
 201 already_AddRefed<gfxASurface>
 202 nsShmImage::EnsureShmImage(const gfxIntSize& aSize, Visual* aVisual, unsigned int aDepth,
 203                nsRefPtr<nsShmImage>& aImage)
 204 {
 205     if (!aImage || aImage->Size() != aSize) {
 206         // Because we XSync() after XShmAttach() to trap errors, we
 207         // know that the X server has the old image's memory mapped
 208         // into its address space, so it's OK to destroy the old image
 209         // here even if there are outstanding Puts.  The Detach is
 210         // ordered after the Puts.
 211         aImage = nsShmImage::Create(aSize, aVisual, aDepth);
 212     }
 213     return !aImage ? nullptr : aImage->AsSurface();
 214 }
 215
 216 #endif  // defined(MOZ_X11) && defined(MOZ_HAVE_SHAREDMEMORYSYSV)