widget/nsIDeviceContextSpec.cpp

   1 /* -*- Mode: C++; tab-width: 2; 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 "nsIDeviceContextSpec.h"
   7
   8 #include "gfxPoint.h"
   9 #include "mozilla/gfx/PrintPromise.h"
  10 #include "nsError.h"
  11 #include "nsIPrintSettings.h"
  12
  13 #include "mozilla/Components.h"
  14 #include "mozilla/TaskQueue.h"
  15
  16 using mozilla::MakeRefPtr;
  17 using mozilla::gfx::PrintEndDocumentPromise;
  18
  19 // We have some platform specific code here rather than in the appropriate
  20 // nsIDeviceContextSpec subclass. We structure the code this way so that
  21 // nsIDeviceContextSpecProxy gets the correct behavior without us having to
  22 // instantiate a platform specific nsIDeviceContextSpec subclass in content
  23 // processes. That is necessary for sandboxing.
  24
  25 float nsIDeviceContextSpec::GetPrintingScale() {
  26 #ifdef XP_WIN
  27   if (mPrintSettings->GetOutputFormat() != nsIPrintSettings::kOutputFormatPDF
  28 #  ifdef MOZ_ENABLE_SKIA_PDF
  29       && !mPrintViaSkPDF
  30 #  endif
  31   ) {
  32     // The print settings will have the resolution stored from the real device.
  33     int32_t resolution;
  34     mPrintSettings->GetResolution(&resolution);
  35     return float(resolution) / GetDPI();
  36   }
  37 #endif
  38
  39   return 72.0f / GetDPI();
  40 }
  41
  42 gfxPoint nsIDeviceContextSpec::GetPrintingTranslate() {
  43 #ifdef XP_WIN
  44   // The underlying surface on windows is the size of the printable region. When
  45   // the region is smaller than the actual paper size the (0, 0) coordinate
  46   // refers top-left of that unwritable region. To instead have (0, 0) become
  47   // the top-left of the actual paper, translate it's coordinate system by the
  48   // unprintable region's width.
  49   double marginTop, marginLeft;
  50   mPrintSettings->GetUnwriteableMarginTop(&marginTop);
  51   mPrintSettings->GetUnwriteableMarginLeft(&marginLeft);
  52   int32_t resolution;
  53   mPrintSettings->GetResolution(&resolution);
  54   return gfxPoint(-marginLeft * resolution, -marginTop * resolution);
  55 #else
  56   return gfxPoint(0, 0);
  57 #endif
  58 }
  59
  60 RefPtr<PrintEndDocumentPromise>
  61 nsIDeviceContextSpec::EndDocumentPromiseFromResult(nsresult aResult,
  62                                                    const char* aSite) {
  63   return NS_SUCCEEDED(aResult)
  64              ? PrintEndDocumentPromise::CreateAndResolve(true, aSite)
  65              : PrintEndDocumentPromise::CreateAndReject(aResult, aSite);
  66 }
  67
  68 RefPtr<PrintEndDocumentPromise> nsIDeviceContextSpec::EndDocumentAsync(
  69     const char* aCallSite, AsyncEndDocumentFunction aFunction) {
  70   auto promise =
  71       MakeRefPtr<PrintEndDocumentPromise::Private>("PrintEndDocumentPromise");
  72
  73   NS_DispatchBackgroundTask(
  74       NS_NewRunnableFunction(
  75           "EndDocumentAsync",
  76           [promise, function = std::move(aFunction)]() mutable {
  77             const auto result = function();
  78             if (NS_SUCCEEDED(result)) {
  79               promise->Resolve(true, __func__);
  80             } else {
  81               promise->Reject(result, __func__);
  82             }
  83           }),
  84       NS_DISPATCH_EVENT_MAY_BLOCK);
  85
  86   return promise;
  87 }