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/* 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
#include "nsPrinterListCUPS.h"
#include "mozilla/IntegerRange.h"
#include "mozilla/Maybe.h"
#include "mozilla/StaticPrefs_print.h"
#include "nsCUPSShim.h"
#include "nsPrinterCUPS.h"
#include "nsString.h"
#include "prenv.h"
// Use a local static to initialize the CUPS shim lazily, when it's needed.
// This is used in order to avoid a global constructor.
static nsCUPSShim& CupsShim() {
static nsCUPSShim sCupsShim;
return sCupsShim;
}
using PrinterInfo = nsPrinterListBase::PrinterInfo;
/**
* Retrieves a human-readable name for the printer from CUPS.
*/
static void GetDisplayNameForPrinter(const cups_dest_t& aDest,
nsAString& aName) {
// macOS clients expect prettified printer names
// while GTK clients expect non-prettified names.
// If you change this, please change NamedPrinter accordingly.
#ifdef XP_MACOSX
const char* displayName = CupsShim().cupsGetOption(
"printer-info", aDest.num_options, aDest.options);
if (displayName) {
CopyUTF8toUTF16(mozilla::MakeStringSpan(displayName), aName);
}
#endif
}
NS_IMETHODIMP
nsPrinterListCUPS::InitPrintSettingsFromPrinter(
const nsAString& aPrinterName, nsIPrintSettings* aPrintSettings) {
MOZ_ASSERT(aPrintSettings);
// Set a default file name.
nsAutoString filename;
nsresult rv = aPrintSettings->GetToFileName(filename);
if (NS_FAILED(rv) || filename.IsEmpty()) {
const char* path = PR_GetEnv("PWD");
if (!path) {
path = PR_GetEnv("HOME");
}
if (path) {
CopyUTF8toUTF16(mozilla::MakeStringSpan(path), filename);
filename.AppendLiteral("/mozilla.pdf");
} else {
filename.AssignLiteral("mozilla.pdf");
}
aPrintSettings->SetToFileName(filename);
}
aPrintSettings->SetIsInitializedFromPrinter(true);
return NS_OK;
}
static int CupsDestCallback(void* user_data, unsigned aFlags,
cups_dest_t* aDest) {
MOZ_ASSERT(user_data);
auto* printerInfoList = static_cast<nsTArray<PrinterInfo>*>(user_data);
cups_dest_t* ownedDest = nullptr;
mozilla::DebugOnly<const int> numCopied =
CupsShim().cupsCopyDest(aDest, 0, &ownedDest);
MOZ_ASSERT(numCopied == 1);
nsString name;
GetDisplayNameForPrinter(*aDest, name);
printerInfoList->AppendElement(PrinterInfo{std::move(name), ownedDest});
return aFlags == CUPS_DEST_FLAGS_MORE ? 1 : 0;
}
nsTArray<PrinterInfo> nsPrinterListCUPS::Printers() const {
if (!CupsShim().InitOkay()) {
return {};
}
auto FreeDestsAndClear = [](nsTArray<PrinterInfo>& aArray) {
for (auto& info : aArray) {
CupsShim().cupsFreeDests(1, static_cast<cups_dest_t*>(info.mCupsHandle));
}
aArray.Clear();
};
nsTArray<PrinterInfo> printerInfoList;
// cupsGetDests2 returns list of found printers without duplicates, unlike
// cupsEnumDests
cups_dest_t* printers = nullptr;
const auto numPrinters = CupsShim().cupsGetDests2(nullptr, &printers);
if (numPrinters > 0) {
for (auto i : mozilla::IntegerRange(0, numPrinters)) {
cups_dest_t* ownedDest = nullptr;
mozilla::DebugOnly<const int> numCopied =
CupsShim().cupsCopyDest(printers + i, 0, &ownedDest);
MOZ_ASSERT(numCopied == 1);
nsString name;
GetDisplayNameForPrinter(*(printers + i), name);
printerInfoList.AppendElement(PrinterInfo{std::move(name), ownedDest});
}
CupsShim().cupsFreeDests(numPrinters, printers);
return printerInfoList;
}
// An error occurred - retry with CUPS_PRINTER_DISCOVERED masked out (since
// it looks like there are a lot of error cases for that in cupsEnumDests):
if (CupsShim().cupsEnumDests(
CUPS_DEST_FLAGS_NONE,
0 /* 0 timeout should be okay when masking CUPS_PRINTER_DISCOVERED */,
nullptr /* cancel* */, CUPS_PRINTER_LOCAL,
CUPS_PRINTER_FAX | CUPS_PRINTER_SCANNER | CUPS_PRINTER_DISCOVERED,
&CupsDestCallback, &printerInfoList)) {
return printerInfoList;
}
// Another error occurred. Maybe printerInfoList could be partially
// populated, so perhaps we could return it without clearing it in the hope
// that there are some usable dests. However, presuambly CUPS doesn't
// guarantee that any dests that it added are complete and safe to use when
// an error occurs?
FreeDestsAndClear(printerInfoList);
return {};
}
RefPtr<nsIPrinter> nsPrinterListCUPS::CreatePrinter(PrinterInfo aInfo) const {
return mozilla::MakeRefPtr<nsPrinterCUPS>(
mCommonPaperInfo, CupsShim(), std::move(aInfo.mName),
static_cast<cups_dest_t*>(aInfo.mCupsHandle));
}
mozilla::Maybe<PrinterInfo> nsPrinterListCUPS::PrinterByName(
nsString aPrinterName) const {
mozilla::Maybe<PrinterInfo> rv;
if (!CupsShim().InitOkay()) {
return rv;
}
// Will contain the printer, if found. This must be fully owned, and not a
// member of another array of printers.
cups_dest_t* printer = nullptr;
#ifdef XP_MACOSX
// On OS X the printer name given to this function is the readable/display
// name and not the CUPS name, so we iterate over all the printers for now.
{
nsAutoCString printerName;
CopyUTF16toUTF8(aPrinterName, printerName);
cups_dest_t* printers = nullptr;
const auto numPrinters = CupsShim().cupsGetDests(&printers);
for (auto i : mozilla::IntegerRange(0, numPrinters)) {
const char* const displayName = CupsShim().cupsGetOption(
"printer-info", printers[i].num_options, printers[i].options);
if (printerName == displayName) {
// The second arg to CupsShim().cupsCopyDest is called num_dests, but
// it actually copies num_dests + 1 elements.
CupsShim().cupsCopyDest(printers + i, 0, &printer);
break;
}
}
CupsShim().cupsFreeDests(numPrinters, printers);
}
#else
// On GTK, we only ever show the CUPS name of printers, so we can use
// cupsGetNamedDest directly.
{
const auto printerName = NS_ConvertUTF16toUTF8(aPrinterName);
printer = CupsShim().cupsGetNamedDest(CUPS_HTTP_DEFAULT, printerName.get(),
nullptr);
}
#endif
if (printer) {
// Since the printer name had to be passed by-value, we can move the
// name from that.
rv.emplace(PrinterInfo{std::move(aPrinterName), printer});
}
return rv;
}
mozilla::Maybe<PrinterInfo> nsPrinterListCUPS::PrinterBySystemName(
nsString aPrinterName) const {
mozilla::Maybe<PrinterInfo> rv;
if (!CupsShim().InitOkay()) {
return rv;
}
const auto printerName = NS_ConvertUTF16toUTF8(aPrinterName);
if (cups_dest_t* const printer = CupsShim().cupsGetNamedDest(
CUPS_HTTP_DEFAULT, printerName.get(), nullptr)) {
rv.emplace(PrinterInfo{std::move(aPrinterName), printer});
}
return rv;
}
nsresult nsPrinterListCUPS::SystemDefaultPrinterName(nsAString& aName) const {
aName.Truncate();
if (!CupsShim().InitOkay()) {
return NS_OK;
}
// Passing in nullptr for the name will return the default, if any.
cups_dest_t* dest =
CupsShim().cupsGetNamedDest(CUPS_HTTP_DEFAULT, /* name */ nullptr,
/* instance */ nullptr);
if (!dest) {
return NS_OK;
}
GetDisplayNameForPrinter(*dest, aName);
if (aName.IsEmpty()) {
CopyUTF8toUTF16(mozilla::MakeStringSpan(dest->name), aName);
}
CupsShim().cupsFreeDests(1, dest);
return NS_OK;
}