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/* -*- Mode: C++; tab-width: 20; 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/. */
#include "PrintTargetPDF.h"
#include "cairo.h"
#include "cairo-pdf.h"
#include "mozilla/AppShutdown.h"
namespace mozilla::gfx {
static cairo_status_t write_func(void* closure, const unsigned char* data,
unsigned int length) {
if (AppShutdown::IsShuttingDown()) {
return CAIRO_STATUS_SUCCESS;
}
nsCOMPtr<nsIOutputStream> out = reinterpret_cast<nsIOutputStream*>(closure);
do {
uint32_t wrote = 0;
if (NS_FAILED(out->Write((const char*)data, length, &wrote))) {
break;
}
data += wrote;
length -= wrote;
} while (length > 0);
NS_ASSERTION(length == 0, "not everything was written to the file");
return CAIRO_STATUS_SUCCESS;
}
PrintTargetPDF::PrintTargetPDF(cairo_surface_t* aCairoSurface,
const IntSize& aSize, nsIOutputStream* aStream)
: PrintTarget(aCairoSurface, aSize), mStream(aStream) {}
PrintTargetPDF::~PrintTargetPDF() {
// We get called first, then PrintTarget's dtor. That means that mStream
// is destroyed before PrintTarget's dtor calls cairo_surface_destroy. This
// can be a problem if Finish() hasn't been called on us, since
// cairo_surface_destroy will then call cairo_surface_finish and that will
// end up invoking write_func above with the by now dangling pointer mStream
// that mCairoSurface stored. To prevent that from happening we must call
// Flush here before mStream is deleted.
Finish();
}
/* static */
already_AddRefed<PrintTargetPDF> PrintTargetPDF::CreateOrNull(
nsIOutputStream* aStream, const IntSize& aSizeInPoints) {
cairo_surface_t* surface = cairo_pdf_surface_create_for_stream(
write_func, (void*)aStream, aSizeInPoints.width, aSizeInPoints.height);
if (cairo_surface_status(surface)) {
return nullptr;
}
// The new object takes ownership of our surface reference.
RefPtr<PrintTargetPDF> target =
new PrintTargetPDF(surface, aSizeInPoints, aStream);
return target.forget();
}
nsresult PrintTargetPDF::EndPage() {
cairo_surface_show_page(mCairoSurface);
return PrintTarget::EndPage();
}
void PrintTargetPDF::Finish() {
if (mIsFinished || AppShutdown::IsShuttingDown()) {
// We don't want to call Close() on mStream more than once, and we don't
// want to block shutdown if for some reason the user shuts down the
// browser mid print.
return;
}
PrintTarget::Finish();
mStream->Close();
}
} // namespace mozilla::gfx