Line data    Source code

       1             : /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
       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 "PrintTargetPDF.h"
       7             : 
       8             : #include "cairo.h"
       9             : #include "cairo-pdf.h"
      10             : 
      11             : namespace mozilla {
      12             : namespace gfx {
      13             : 
      14             : static cairo_status_t
      15           0 : write_func(void *closure, const unsigned char *data, unsigned int length)
      16             : {
      17           0 :   nsCOMPtr<nsIOutputStream> out = reinterpret_cast<nsIOutputStream*>(closure);
      18           0 :   do {
      19           0 :     uint32_t wrote = 0;
      20           0 :     if (NS_FAILED(out->Write((const char*)data, length, &wrote))) {
      21           0 :       break;
      22             :     }
      23           0 :     data += wrote; length -= wrote;
      24           0 :   } while (length > 0);
      25           0 :   NS_ASSERTION(length == 0, "not everything was written to the file");
      26           0 :   return CAIRO_STATUS_SUCCESS;
      27             : }
      28             : 
      29           0 : PrintTargetPDF::PrintTargetPDF(cairo_surface_t* aCairoSurface,
      30             :                                const IntSize& aSize,
      31           0 :                                nsIOutputStream *aStream)
      32             :   : PrintTarget(aCairoSurface, aSize)
      33           0 :   , mStream(aStream)
      34             : {
      35           0 : }
      36             : 
      37           0 : PrintTargetPDF::~PrintTargetPDF()
      38             : {
      39             :   // We get called first, then PrintTarget's dtor.  That means that mStream
      40             :   // is destroyed before PrintTarget's dtor calls cairo_surface_destroy.  This
      41             :   // can be a problem if Finish() hasn't been called on us, since
      42             :   // cairo_surface_destroy will then call cairo_surface_finish and that will
      43             :   // end up invoking write_func above with the by now dangling pointer mStream
      44             :   // that mCairoSurface stored.  To prevent that from happening we must call
      45             :   // Flush here before mStream is deleted.
      46           0 :   Finish();
      47           0 : }
      48             : 
      49             : /* static */ already_AddRefed<PrintTargetPDF>
      50           0 : PrintTargetPDF::CreateOrNull(nsIOutputStream *aStream,
      51             :                              const IntSize& aSizeInPoints)
      52             : {
      53             :   cairo_surface_t* surface =
      54           0 :     cairo_pdf_surface_create_for_stream(write_func, (void*)aStream,
      55           0 :                                         aSizeInPoints.width,
      56           0 :                                         aSizeInPoints.height);
      57           0 :   if (cairo_surface_status(surface)) {
      58           0 :     return nullptr;
      59             :   }
      60             : 
      61             :   // The new object takes ownership of our surface reference.
      62             :   RefPtr<PrintTargetPDF> target = new PrintTargetPDF(surface, aSizeInPoints,
      63           0 :                                                      aStream);
      64           0 :   return target.forget();
      65             : }
      66             : 
      67             : nsresult
      68           0 : PrintTargetPDF::EndPage()
      69             : {
      70           0 :   cairo_surface_show_page(mCairoSurface);
      71           0 :   return PrintTarget::EndPage();
      72             : }
      73             : 
      74             : void
      75           0 : PrintTargetPDF::Finish()
      76             : {
      77           0 :   if (mIsFinished) {
      78           0 :     return; // We don't want to call Close() on mStream more than once
      79             :   }
      80           0 :   PrintTarget::Finish();
      81           0 :   mStream->Close();
      82             : }
      83             : 
      84             : } // namespace gfx
      85             : } // namespace mozilla