gfx/thebes/gfxXlibSurface.cpp

   1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "gfxXlibSurface.h"
   7
   8 #include "cairo.h"
   9 #include "cairo-xlib.h"
  10 #include <X11/Xlibint.h> /* For XESetCloseDisplay */
  11 #undef max               // Xlibint.h defines this and it breaks std::max
  12 #undef min               // Xlibint.h defines this and it breaks std::min
  13 #undef Data
  14
  15 #include "nsTArray.h"
  16 #include "nsAlgorithm.h"
  17 #include "mozilla/gfx/2D.h"
  18 #include "mozilla/Preferences.h"
  19 #include <algorithm>
  20 #include "mozilla/CheckedInt.h"
  21
  22 using namespace mozilla;
  23 using namespace mozilla::gfx;
  24
  25 gfxXlibSurface::gfxXlibSurface(Display* dpy, Drawable drawable, Visual* visual)
  26     : mPixmapTaken(false),
  27       mDisplay(XlibDisplay::Borrow(dpy)),
  28       mDrawable(drawable) {
  29   const gfx::IntSize size = DoSizeQuery();
  30   cairo_surface_t* surf =
  31       cairo_xlib_surface_create(dpy, drawable, visual, size.width, size.height);
  32   Init(surf);
  33 }
  34
  35 gfxXlibSurface::gfxXlibSurface(Display* dpy, Drawable drawable, Visual* visual,
  36                                const gfx::IntSize& size)
  37     : gfxXlibSurface(XlibDisplay::Borrow(dpy), drawable, visual, size) {}
  38
  39 gfxXlibSurface::gfxXlibSurface(const std::shared_ptr<XlibDisplay>& dpy,
  40                                Drawable drawable, Visual* visual,
  41                                const gfx::IntSize& size)
  42     : mPixmapTaken(false), mDisplay(dpy), mDrawable(drawable) {
  43   NS_ASSERTION(Factory::CheckSurfaceSize(size, XLIB_IMAGE_SIDE_SIZE_LIMIT),
  44                "Bad size");
  45
  46   cairo_surface_t* surf = cairo_xlib_surface_create(*dpy, drawable, visual,
  47                                                     size.width, size.height);
  48   Init(surf);
  49 }
  50
  51 gfxXlibSurface::gfxXlibSurface(cairo_surface_t* csurf) : mPixmapTaken(false) {
  52   MOZ_ASSERT(cairo_surface_status(csurf) == 0,
  53              "Not expecting an error surface");
  54
  55   mDrawable = cairo_xlib_surface_get_drawable(csurf);
  56   mDisplay = XlibDisplay::Borrow(cairo_xlib_surface_get_display(csurf));
  57
  58   Init(csurf, true);
  59 }
  60
  61 gfxXlibSurface::~gfxXlibSurface() {
  62   // gfxASurface's destructor calls RecordMemoryFreed().
  63   if (mPixmapTaken) {
  64     XFreePixmap(*mDisplay, mDrawable);
  65   }
  66 }
  67
  68 static Drawable CreatePixmap(Screen* screen, const gfx::IntSize& size,
  69                              unsigned int depth, Drawable relatedDrawable) {
  70   if (!Factory::CheckSurfaceSize(size, XLIB_IMAGE_SIDE_SIZE_LIMIT))
  71     return X11None;
  72
  73   if (relatedDrawable == X11None) {
  74     relatedDrawable = RootWindowOfScreen(screen);
  75   }
  76   Display* dpy = DisplayOfScreen(screen);
  77   // X gives us a fatal error if we try to create a pixmap of width
  78   // or height 0
  79   return XCreatePixmap(dpy, relatedDrawable, std::max(1, size.width),
  80                        std::max(1, size.height), depth);
  81 }
  82
  83 void gfxXlibSurface::TakePixmap() {
  84   NS_ASSERTION(!mPixmapTaken, "I already own the Pixmap!");
  85   mPixmapTaken = true;
  86
  87   // The bit depth returned from Cairo is technically int, but this is
  88   // the last place we'd be worried about that scenario.
  89   unsigned int bitDepth = cairo_xlib_surface_get_depth(CairoSurface());
  90   MOZ_ASSERT((bitDepth % 8) == 0, "Memory used not recorded correctly");
  91
  92   // Divide by 8 because surface_get_depth gives us the number of *bits* per
  93   // pixel.
  94   gfx::IntSize size = GetSize();
  95   CheckedInt32 totalBytes =
  96       CheckedInt32(size.width) * CheckedInt32(size.height) * (bitDepth / 8);
  97
  98   // Don't do anything in the "else" case.  We could add INT32_MAX, but that
  99   // would overflow the memory used counter.  It would also mean we tried for
 100   // a 2G image.  For now, we'll just assert,
 101   MOZ_ASSERT(totalBytes.isValid(), "Did not expect to exceed 2Gb image");
 102   if (totalBytes.isValid()) {
 103     RecordMemoryUsed(totalBytes.value());
 104   }
 105 }
 106
 107 Drawable gfxXlibSurface::ReleasePixmap() {
 108   NS_ASSERTION(mPixmapTaken, "I don't own the Pixmap!");
 109   mPixmapTaken = false;
 110   RecordMemoryFreed();
 111   return mDrawable;
 112 }
 113
 114 static cairo_user_data_key_t gDestroyPixmapKey;
 115
 116 struct DestroyPixmapClosure {
 117   DestroyPixmapClosure(Drawable d, Screen* s) : mPixmap(d), mScreen(s) {}
 118   Drawable mPixmap;
 119   Screen* mScreen;
 120 };
 121
 122 static void DestroyPixmap(void* data) {
 123   DestroyPixmapClosure* closure = static_cast<DestroyPixmapClosure*>(data);
 124   XFreePixmap(DisplayOfScreen(closure->mScreen), closure->mPixmap);
 125   delete closure;
 126 }
 127
 128 /* static */
 129 cairo_surface_t* gfxXlibSurface::CreateCairoSurface(Screen* screen,
 130                                                     Visual* visual,
 131                                                     const gfx::IntSize& size,
 132                                                     Drawable relatedDrawable) {
 133   Drawable drawable = CreatePixmap(screen, size, DepthOfVisual(screen, visual),
 134                                    relatedDrawable);
 135   if (!drawable) return nullptr;
 136
 137   cairo_surface_t* surface = cairo_xlib_surface_create(
 138       DisplayOfScreen(screen), drawable, visual, size.width, size.height);
 139   if (cairo_surface_status(surface)) {
 140     cairo_surface_destroy(surface);
 141     XFreePixmap(DisplayOfScreen(screen), drawable);
 142     return nullptr;
 143   }
 144
 145   DestroyPixmapClosure* closure = new DestroyPixmapClosure(drawable, screen);
 146   cairo_surface_set_user_data(surface, &gDestroyPixmapKey, closure,
 147                               DestroyPixmap);
 148   return surface;
 149 }
 150
 151 /* static */
 152 already_AddRefed<gfxXlibSurface> gfxXlibSurface::Create(
 153     Screen* screen, Visual* visual, const gfx::IntSize& size,
 154     Drawable relatedDrawable) {
 155   return Create(XlibDisplay::Borrow(DisplayOfScreen(screen)), screen, visual,
 156                 size, relatedDrawable);
 157 };
 158
 159 /* static */
 160 already_AddRefed<gfxXlibSurface> gfxXlibSurface::Create(
 161     const std::shared_ptr<XlibDisplay>& display, Screen* screen, Visual* visual,
 162     const gfx::IntSize& size, Drawable relatedDrawable) {
 163   MOZ_ASSERT(*display == DisplayOfScreen(screen));
 164
 165   Drawable drawable = CreatePixmap(screen, size, DepthOfVisual(screen, visual),
 166                                    relatedDrawable);
 167   if (!drawable) return nullptr;
 168
 169   RefPtr<gfxXlibSurface> result =
 170       new gfxXlibSurface(display, drawable, visual, size);
 171   result->TakePixmap();
 172
 173   if (result->CairoStatus() != 0) return nullptr;
 174
 175   return result.forget();
 176 }
 177
 178 void gfxXlibSurface::Finish() { gfxASurface::Finish(); }
 179
 180 const gfx::IntSize gfxXlibSurface::GetSize() const {
 181   if (!mSurfaceValid) return gfx::IntSize(0, 0);
 182
 183   return gfx::IntSize(cairo_xlib_surface_get_width(mSurface),
 184                       cairo_xlib_surface_get_height(mSurface));
 185 }
 186
 187 const gfx::IntSize gfxXlibSurface::DoSizeQuery() {
 188   // figure out width/height/depth
 189   Window root_ignore;
 190   int x_ignore, y_ignore;
 191   unsigned int bwidth_ignore, width, height, depth;
 192
 193   XGetGeometry(*mDisplay, mDrawable, &root_ignore, &x_ignore, &y_ignore, &width,
 194                &height, &bwidth_ignore, &depth);
 195
 196   return gfx::IntSize(width, height);
 197 }
 198
 199 class DisplayTable {
 200  public:
 201   static bool GetColormapAndVisual(Screen* screen, Visual* visual,
 202                                    Colormap* colormap,
 203                                    Visual** visualForColormap);
 204
 205  private:
 206   struct ColormapEntry {
 207     // The Screen is needed here because colormaps (and their visuals) may
 208     // only be used on one Screen
 209     Screen* mScreen;
 210     Visual* mVisual;
 211     Colormap mColormap;
 212   };
 213
 214   class DisplayInfo {
 215    public:
 216     explicit DisplayInfo(Display* display) : mDisplay(display) {}
 217     Display* mDisplay;
 218     nsTArray<ColormapEntry> mColormapEntries;
 219   };
 220
 221   // Comparator for finding the DisplayInfo
 222   class FindDisplay {
 223    public:
 224     bool Equals(const DisplayInfo& info, const Display* display) const {
 225       return info.mDisplay == display;
 226     }
 227   };
 228
 229   static int DisplayClosing(Display* display, XExtCodes* codes);
 230
 231   nsTArray<DisplayInfo> mDisplays;
 232   static DisplayTable* sDisplayTable;
 233 };
 234
 235 DisplayTable* DisplayTable::sDisplayTable;
 236
 237 // Pixmaps don't have a particular associated visual but the pixel values are
 238 // interpreted according to a visual/colormap pairs.
 239 //
 240 // cairo is designed for surfaces with either TrueColor visuals or the
 241 // default visual (which may not be true color).  TrueColor visuals don't
 242 // really need a colormap because the visual indicates the pixel format,
 243 // and cairo uses the default visual with the default colormap, so cairo
 244 // surfaces don't need an explicit colormap.
 245 //
 246 // However, some toolkits (e.g. GDK) need a colormap even with TrueColor
 247 // visuals.  We can create a colormap for these visuals, but it will use about
 248 // 20kB of memory in the server, so we use the default colormap when
 249 // suitable and share colormaps between surfaces.  Another reason for
 250 // minimizing colormap turnover is that the plugin process must leak resources
 251 // for each new colormap id when using older GDK libraries (bug 569775).
 252 //
 253 // Only the format of the pixels is important for rendering to Pixmaps, so if
 254 // the format of a visual matches that of the surface, then that visual can be
 255 // used for rendering to the surface.  Multiple visuals can match the same
 256 // format (but have different GLX properties), so the visual returned may
 257 // differ from the visual passed in.  Colormaps are tied to a visual, so
 258 // should only be used with their visual.
 259
 260 /* static */
 261 bool DisplayTable::GetColormapAndVisual(Screen* aScreen, Visual* aVisual,
 262                                         Colormap* aColormap,
 263                                         Visual** aVisualForColormap)
 264
 265 {
 266   Display* display = DisplayOfScreen(aScreen);
 267
 268   // Use the default colormap if the default visual matches.
 269   Visual* defaultVisual = DefaultVisualOfScreen(aScreen);
 270   if (aVisual == defaultVisual) {
 271     *aColormap = DefaultColormapOfScreen(aScreen);
 272     *aVisualForColormap = defaultVisual;
 273     return true;
 274   }
 275
 276   // Only supporting TrueColor non-default visuals
 277   if (!aVisual || aVisual->c_class != TrueColor) return false;
 278
 279   if (!sDisplayTable) {
 280     sDisplayTable = new DisplayTable();
 281   }
 282
 283   nsTArray<DisplayInfo>* displays = &sDisplayTable->mDisplays;
 284   size_t d = displays->IndexOf(display, 0, FindDisplay());
 285
 286   if (d == displays->NoIndex) {
 287     d = displays->Length();
 288     // Register for notification of display closing, when this info
 289     // becomes invalid.
 290     XExtCodes* codes = XAddExtension(display);
 291     if (!codes) return false;
 292
 293     XESetCloseDisplay(display, codes->extension, DisplayClosing);
 294     // Add a new DisplayInfo.
 295     displays->AppendElement(display);
 296   }
 297
 298   nsTArray<ColormapEntry>* entries = &displays->ElementAt(d).mColormapEntries;
 299
 300   // Only a small number of formats are expected to be used, so just do a
 301   // simple linear search.
 302   for (uint32_t i = 0; i < entries->Length(); ++i) {
 303     const ColormapEntry& entry = entries->ElementAt(i);
 304     if (aVisual == entry.mVisual) {
 305       *aColormap = entry.mColormap;
 306       *aVisualForColormap = entry.mVisual;
 307       return true;
 308     }
 309   }
 310
 311   // No existing entry.  Create a colormap and add an entry.
 312   Colormap colormap =
 313       XCreateColormap(display, RootWindowOfScreen(aScreen), aVisual, AllocNone);
 314   ColormapEntry* newEntry = entries->AppendElement();
 315   newEntry->mScreen = aScreen;
 316   newEntry->mVisual = aVisual;
 317   newEntry->mColormap = colormap;
 318
 319   *aColormap = colormap;
 320   *aVisualForColormap = aVisual;
 321   return true;
 322 }
 323
 324 /* static */
 325 int DisplayTable::DisplayClosing(Display* display, XExtCodes* codes) {
 326   // No need to free the colormaps explicitly as they will be released when
 327   // the connection is closed.
 328   sDisplayTable->mDisplays.RemoveElement(display, FindDisplay());
 329   if (sDisplayTable->mDisplays.Length() == 0) {
 330     delete sDisplayTable;
 331     sDisplayTable = nullptr;
 332   }
 333   return 0;
 334 }
 335
 336 /* static */
 337 bool gfxXlibSurface::GetColormapAndVisual(cairo_surface_t* aXlibSurface,
 338                                           Colormap* aColormap,
 339                                           Visual** aVisual) {
 340   Screen* screen = cairo_xlib_surface_get_screen(aXlibSurface);
 341   Visual* visual = cairo_xlib_surface_get_visual(aXlibSurface);
 342
 343   return DisplayTable::GetColormapAndVisual(screen, visual, aColormap, aVisual);
 344 }
 345
 346 bool gfxXlibSurface::GetColormapAndVisual(Colormap* aColormap,
 347                                           Visual** aVisual) {
 348   if (!mSurfaceValid) return false;
 349
 350   return GetColormapAndVisual(CairoSurface(), aColormap, aVisual);
 351 }
 352
 353 /* static */
 354 int gfxXlibSurface::DepthOfVisual(const Screen* screen, const Visual* visual) {
 355   for (int d = 0; d < screen->ndepths; d++) {
 356     const Depth& d_info = screen->depths[d];
 357     if (visual >= &d_info.visuals[0] &&
 358         visual < &d_info.visuals[d_info.nvisuals])
 359       return d_info.depth;
 360   }
 361
 362   NS_ERROR("Visual not on Screen.");
 363   return 0;
 364 }
 365
 366 /* static */
 367 Visual* gfxXlibSurface::FindVisual(Screen* screen, gfxImageFormat format) {
 368   int depth;
 369   unsigned long red_mask, green_mask, blue_mask;
 370   switch (format) {
 371     case gfx::SurfaceFormat::A8R8G8B8_UINT32:
 372       depth = 32;
 373       red_mask = 0xff0000;
 374       green_mask = 0xff00;
 375       blue_mask = 0xff;
 376       break;
 377     case gfx::SurfaceFormat::X8R8G8B8_UINT32:
 378       depth = 24;
 379       red_mask = 0xff0000;
 380       green_mask = 0xff00;
 381       blue_mask = 0xff;
 382       break;
 383     case gfx::SurfaceFormat::R5G6B5_UINT16:
 384       depth = 16;
 385       red_mask = 0xf800;
 386       green_mask = 0x7e0;
 387       blue_mask = 0x1f;
 388       break;
 389     case gfx::SurfaceFormat::A8:
 390     default:
 391       return nullptr;
 392   }
 393
 394   for (int d = 0; d < screen->ndepths; d++) {
 395     const Depth& d_info = screen->depths[d];
 396     if (d_info.depth != depth) continue;
 397
 398     for (int v = 0; v < d_info.nvisuals; v++) {
 399       Visual* visual = &d_info.visuals[v];
 400
 401       if (visual->c_class == TrueColor && visual->red_mask == red_mask &&
 402           visual->green_mask == green_mask && visual->blue_mask == blue_mask)
 403         return visual;
 404     }
 405   }
 406
 407   return nullptr;
 408 }
 409
 410 Screen* gfxXlibSurface::XScreen() {
 411   return cairo_xlib_surface_get_screen(CairoSurface());
 412 }