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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 */
#include "PrintTargetPS.h"
#include "cairo.h"
#include "cairo-ps.h"
namespace mozilla::gfx {
static cairo_status_t write_func(void* closure, const unsigned char* data,
unsigned int length) {
nsCOMPtr<nsIOutputStream> out = reinterpret_cast<nsIOutputStream*>(closure);
do {
uint32_t wrote = 0;
if (NS_FAILED(out->Write((const char*)data, length, &wrote))) {
data += wrote;
length -= wrote;
} while (length > 0);
NS_ASSERTION(length == 0, "not everything was written to the file");
PrintTargetPS::PrintTargetPS(cairo_surface_t* aCairoSurface,
const IntSize& aSize, nsIOutputStream* aStream,
PageOrientation aOrientation)
: PrintTarget(aCairoSurface, aSize),
mOrientation(aOrientation) {}
PrintTargetPS::~PrintTargetPS() {
// 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.
/* static */
already_AddRefed<PrintTargetPS> PrintTargetPS::CreateOrNull(
nsIOutputStream* aStream, IntSize aSizeInPoints,
PageOrientation aOrientation) {
// The PS output does not specify the page size so to print landscape we need
// to rotate the drawing 90 degrees and print on portrait paper. If printing
// landscape, swap the width/height supplied to cairo to select a portrait
// print area. Our consumers are responsible for checking
// RotateForLandscape() and applying a rotation transform if true.
if (aOrientation == LANDSCAPE) {
std::swap(aSizeInPoints.width, aSizeInPoints.height);
cairo_surface_t* surface = cairo_ps_surface_create_for_stream(
write_func, (void*)aStream, aSizeInPoints.width, aSizeInPoints.height);
if (cairo_surface_status(surface)) {
return nullptr;
cairo_ps_surface_restrict_to_level(surface, CAIRO_PS_LEVEL_2);
// The new object takes ownership of our surface reference.
RefPtr<PrintTargetPS> target =
new PrintTargetPS(surface, aSizeInPoints, aStream, aOrientation);
return target.forget();
nsresult PrintTargetPS::BeginPrinting(const nsAString& aTitle,
const nsAString& aPrintToFileName,
int32_t aStartPage, int32_t aEndPage) {
if (mOrientation == PORTRAIT) {
cairo_ps_surface_dsc_comment(mCairoSurface, "%%Orientation: Portrait");
} else {
cairo_ps_surface_dsc_comment(mCairoSurface, "%%Orientation: Landscape");
return NS_OK;
nsresult PrintTargetPS::EndPage() {
return NS_OK;
void PrintTargetPS::Finish() {
if (mIsFinished) {
return; // We don't want to call Close() on mStream more than once
} // namespace mozilla::gfx