Bug 1655558 - Retrieve paper information from CUPS, and convert paperList to an async attribute. r=jwatt

This builds on top of bug 1656146 to compute the page information on a
background task, and return it via a promise.

Co-Authored-By: Erik Nordin <enordin@mozilla.com>

Differential Revision: https://phabricator.services.mozilla.com/D85865

layout/base/tests/chrome/test_get_printer_paper_sizes.html

@@ -8,7 +8,7 @@
 
 SimpleTest.waitForExplicitFinish();
 
-function run() {
+async function run() {
   try {
     let printerList = Cc["@mozilla.org/gfx/printerlist;1"].getService(
       Ci.nsIPrinterList
@@ -16,10 +16,17 @@ function run() {
     if (printerList.printers.length == 0) {
       ok(true, "There were no printers to iterate through.");
     }
-    printerList.printers.forEach(printer => {
+
+    for (let printer of printerList.printers) {
       isnot(printer.name, null, "Printer name should never be null.");
       isnot(printer.name, "", "Printer name should never be empty.");
-      printer.paperList.forEach(paper => {
+      info(printer.name);
+
+      let paperList = await printer.paperList;
+      for (let paper of paperList) {
+        paper.QueryInterface(Ci.nsIPaper);
+
+        info(`${paper.name}: ${paper.width}x${paper.height} with margin: ${paper.unwriteableMarginTop} ${paper.unwriteableMarginRight} ${paper.unwriteableMarginBottom} ${paper.unwriteableMarginLeft}`);
         isnot(paper.name, null, "Paper name should never be null.");
         isnot(paper.name, "", "Paper name should never be empty.");
 
@@ -28,8 +35,20 @@ function run() {
 
         isnot(paper.height, null, "Paper height should never be null.");
         ok(paper.height > 0.0, "Paper height should be greater than zero.");
-      });
-    })
+
+        isnot(paper.unwriteableMarginTop, null, "Paper unwriteableMarginTop should never be null.");
+        ok(paper.unwriteableMarginTop >= 0.0, "Paper unwriteableMarginTop should be greater than or equal to zero.");
+
+        isnot(paper.unwriteableMarginBottom, null, "Paper unwriteableMarginBottom should never be null.");
+        ok(paper.unwriteableMarginBottom >= 0.0, "Paper unwriteableMarginBottom should be greater than or equal to zero.");
+
+        isnot(paper.unwriteableMarginLeft, null, "Paper unwriteableMarginLeft should never be null.");
+        ok(paper.unwriteableMarginLeft >= 0.0, "Paper unwriteableMarginLeft should be greater than or equal to zero.");
+
+        isnot(paper.unwriteableMarginRight, null, "Paper unwriteableMarginRight should never be null.");
+        ok(paper.unwriteableMarginRight >= 0.0, "Paper unwriteableMarginRight should be greater than or equal to zero.");
+      }
+    }
   } catch (e) {
     Cu.reportError(e);
   }

widget/cocoa/nsDeviceContextSpecX.mm

@@ -47,71 +47,14 @@ static LazyLogModule sDeviceContextSpecXLog("DeviceContextSpecX");
 
 static nsCUPSShim sCupsShim;
 
-/**
- * Retrieves the list of available paper options for a given printer name.
- */
-static nsresult FillPaperListForPrinter(PMPrinter aPrinter,
-                                        nsTArray<RefPtr<nsIPaper>>& aPaperList) {
-  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
-
-  CFArrayRef pmPaperList;
-  aPaperList.ClearAndRetainStorage();
-  OSStatus status = PMPrinterGetPaperList(aPrinter, &pmPaperList);
-  if (status != noErr || !pmPaperList) {
-    return NS_ERROR_UNEXPECTED;
-  }
-
-  CFIndex paperCount = CFArrayGetCount(pmPaperList);
-  aPaperList.SetCapacity(paperCount);
-
-  for (auto i = 0; i < paperCount; ++i) {
-    PMPaper pmPaper =
-        static_cast<PMPaper>(const_cast<void*>(CFArrayGetValueAtIndex(pmPaperList, i)));
-
-    // The units for width and height are points.
-    double width = 0.0;
-    double height = 0.0;
-    AutoCFRelease<CFStringRef> pmPaperName(nullptr);
-    if (PMPaperGetWidth(pmPaper, &width) != noErr || PMPaperGetHeight(pmPaper, &height) != noErr ||
-        PMPaperCreateLocalizedName(pmPaper, aPrinter, pmPaperName.receive()) != noErr) {
-      return NS_ERROR_UNEXPECTED;
-    }
-
-    nsAutoString name;
-    nsCocoaUtils::GetStringForNSString(static_cast<NSString*>(CFStringRef(pmPaperName)), name);
-
-    PMPaperMargins unwriteableMargins;
-    if (PMPaperGetMargins(pmPaper, &unwriteableMargins) != noErr) {
-      // If we can't get unwriteable margins, just default to none.
-      unwriteableMargins.top = 0.0;
-      unwriteableMargins.bottom = 0.0;
-      unwriteableMargins.left = 0.0;
-      unwriteableMargins.right = 0.0;
-    }
-
-    aPaperList.AppendElement(new nsPaper(name, width, height, unwriteableMargins.top,
-                                         unwriteableMargins.bottom, unwriteableMargins.left,
-                                         unwriteableMargins.right));
-  }
-
-  return NS_OK;
-
-  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
-}
-
 static nsresult CreatePrinter(mozilla::CUPSPrinterList& aCupsPrinterList, PMPrinter aPMPrinter,
                               nsIPrinter** aPrinter) {
   NS_ENSURE_ARG_POINTER(aPrinter);
   *aPrinter = nullptr;
 
-  nsTArray<RefPtr<nsIPaper>> paperList;
-  nsresult rv = FillPaperListForPrinter(aPMPrinter, paperList);
-  NS_ENSURE_SUCCESS(rv, rv);
-
   NSString* const printerID = static_cast<NSString*>(PMPrinterGetID(aPMPrinter));
   if (cups_dest_t* const dest = aCupsPrinterList.FindPrinterByName([printerID UTF8String])) {
-    if (RefPtr<nsPrinterCUPS> printer =
-            nsPrinterCUPS::Create(sCupsShim, dest, std::move(paperList))) {
+    if (RefPtr<nsPrinterCUPS> printer = nsPrinterCUPS::Create(sCupsShim, dest)) {
       printer.forget(aPrinter);
       return NS_OK;
     }

widget/moz.build

@@ -236,16 +236,12 @@ if CONFIG['MOZ_XUL'] and CONFIG['NS_PRINTING']:
     ]
     UNIFIED_SOURCES += [
         'nsDeviceContextSpecProxy.cpp',
+        'nsPaper.cpp',
         'nsPrinterBase.cpp',
         'nsPrintSession.cpp',
         'nsPrintSettingsService.cpp',
     ]
 
-    # The Windows sub-directory has its own implemenation of these.
-    if toolkit != 'windows':
-        UNIFIED_SOURCES += [
-            'nsPaper.cpp',
-        ]
     # These will be unified for all CUPS platforms by Bug 1654678
     if toolkit == 'cocoa':
         UNIFIED_SOURCES += [
@@ -253,6 +249,7 @@ if CONFIG['MOZ_XUL'] and CONFIG['NS_PRINTING']:
             'nsCUPSShim.cpp',
             'nsPrinterCUPS.cpp',
         ]
+
     if toolkit == 'gtk':
         UNIFIED_SOURCES += [
             'nsCUPSShim.cpp',

widget/nsCUPSShim.cpp

@@ -49,14 +49,19 @@ bool nsCUPSShim::Init() {
 
   if (!(CUPS_SHIM_LOAD(mCupsAddOption, cupsAddOption) &&
         CUPS_SHIM_LOAD(mCupsCheckDestSupported, cupsCheckDestSupported) &&
+        CUPS_SHIM_LOAD(mCupsConnectDest, cupsConnectDest) &&
         CUPS_SHIM_LOAD(mCupsCopyDest, cupsCopyDest) &&
         CUPS_SHIM_LOAD(mCupsCopyDestInfo, cupsCopyDestInfo) &&
         CUPS_SHIM_LOAD(mCupsFreeDestInfo, cupsFreeDestInfo) &&
         CUPS_SHIM_LOAD(mCupsFreeDests, cupsFreeDests) &&
+        CUPS_SHIM_LOAD(mCupsGetDestMediaCount, cupsGetDestMediaCount) &&
+        CUPS_SHIM_LOAD(mCupsGetDestMediaByIndex, cupsGetDestMediaByIndex) &&
         CUPS_SHIM_LOAD(mCupsGetDest, cupsGetDest) &&
         CUPS_SHIM_LOAD(mCupsGetDests, cupsGetDests) &&
+        CUPS_SHIM_LOAD(mCupsLocalizeDestMedia, cupsLocalizeDestMedia) &&
         CUPS_SHIM_LOAD(mCupsPrintFile, cupsPrintFile) &&
-        CUPS_SHIM_LOAD(mCupsTempFd, cupsTempFd))) {
+        CUPS_SHIM_LOAD(mCupsTempFd, cupsTempFd) &&
+        CUPS_SHIM_LOAD(mHttpClose, httpClose))) {
 #ifndef MOZ_TSAN
     // With TSan, we cannot unload libcups once we have loaded it because
     // TSan does not support unloading libraries that are matched from its

widget/nsCUPSShim.h

@@ -35,14 +35,19 @@ class nsCUPSShim {
    */
   decltype(cupsAddOption)* mCupsAddOption;
   decltype(cupsCheckDestSupported)* mCupsCheckDestSupported;
+  decltype(cupsConnectDest)* mCupsConnectDest;
   decltype(cupsCopyDest)* mCupsCopyDest;
   decltype(cupsCopyDestInfo)* mCupsCopyDestInfo;
   decltype(cupsFreeDestInfo)* mCupsFreeDestInfo;
   decltype(cupsFreeDests)* mCupsFreeDests;
+  decltype(cupsGetDestMediaCount)* mCupsGetDestMediaCount;
+  decltype(cupsGetDestMediaByIndex)* mCupsGetDestMediaByIndex;
   decltype(cupsGetDest)* mCupsGetDest;
   decltype(cupsGetDests)* mCupsGetDests;
+  decltype(cupsLocalizeDestMedia)* mCupsLocalizeDestMedia;
   decltype(cupsPrintFile)* mCupsPrintFile;
   decltype(cupsTempFd)* mCupsTempFd;
+  decltype(httpClose)* mHttpClose;
 
  private:
   bool mInited = false;

widget/nsIPrinter.idl

@@ -15,9 +15,12 @@ interface nsIPrinter : nsISupports
   readonly attribute AString name;
 
   /**
-   * The list of available paper sizes.
+   * Returns a Promise that resolves to an array of
+   * nsIPaper instances with the list of available paper
+   * sizes.
    */
-  readonly attribute Array<nsIPaper> paperList;
+  [implicit_jscontext]
+  readonly attribute Promise paperList;
 
   /**
    * Returns a Promise that resolves to true or false to indicate whether this

widget/nsPaper.cpp

@@ -9,48 +9,48 @@ NS_IMPL_ISUPPORTS(nsPaper, nsIPaper);
 
 NS_IMETHODIMP
 nsPaper::GetName(nsAString& aName) {
-  aName = mName;
+  aName = mInfo.mName;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetWidth(double* aWidth) {
   NS_ENSURE_ARG_POINTER(aWidth);
-  *aWidth = mWidth;
+  *aWidth = mInfo.mWidth;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetHeight(double* aHeight) {
   NS_ENSURE_ARG_POINTER(aHeight);
-  *aHeight = mHeight;
+  *aHeight = mInfo.mHeight;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetUnwriteableMarginTop(double* aUnwriteableMarginTop) {
   NS_ENSURE_ARG_POINTER(aUnwriteableMarginTop);
-  *aUnwriteableMarginTop = mUnwriteableMarginTop;
+  *aUnwriteableMarginTop = mInfo.mUnwriteableMarginTop;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetUnwriteableMarginBottom(double* aUnwriteableMarginBottom) {
   NS_ENSURE_ARG_POINTER(aUnwriteableMarginBottom);
-  *aUnwriteableMarginBottom = mUnwriteableMarginBottom;
+  *aUnwriteableMarginBottom = mInfo.mUnwriteableMarginBottom;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetUnwriteableMarginLeft(double* aUnwriteableMarginLeft) {
   NS_ENSURE_ARG_POINTER(aUnwriteableMarginLeft);
-  *aUnwriteableMarginLeft = mUnwriteableMarginLeft;
+  *aUnwriteableMarginLeft = mInfo.mUnwriteableMarginLeft;
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsPaper::GetUnwriteableMarginRight(double* aUnwriteableMarginRight) {
   NS_ENSURE_ARG_POINTER(aUnwriteableMarginRight);
-  *aUnwriteableMarginRight = mUnwriteableMarginRight;
+  *aUnwriteableMarginRight = mInfo.mUnwriteableMarginRight;
   return NS_OK;
 }

widget/nsPaper.h

@@ -6,36 +6,53 @@
 #ifndef nsPaper_h__
 #define nsPaper_h__
 
+#include "mozilla/dom/ToJSValue.h"
+#include "js/TypeDecls.h"
 #include "nsIPaper.h"
 #include "nsISupportsImpl.h"
+#include "js/RootingAPI.h"
 #include "nsString.h"
 
+namespace mozilla {
+
+// Simple struct that can be used off the main thread to hold all the info from
+// an nsPaper instance.
+struct PaperInfo {
+  const nsString mName;
+  const double mWidth;
+  const double mHeight;
+  const double mUnwriteableMarginTop;
+  const double mUnwriteableMarginRight;
+  const double mUnwriteableMarginBottom;
+  const double mUnwriteableMarginLeft;
+};
+
+}  // namespace mozilla
+
 class nsPaper final : public nsIPaper {
  public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSIPAPER
   nsPaper() = delete;
-  nsPaper(nsAString& aName, double aWidth, double aHeight,
-          double aUnwriteableMarginTop, double aUnwriteableMarginBottom,
-          double aUnwriteableMarginLeft, double aUnwriteableMarginRight)
-      : mName(aName),
-        mWidth(aWidth),
-        mHeight(aHeight),
-        mUnwriteableMarginTop(aUnwriteableMarginTop),
-        mUnwriteableMarginBottom(aUnwriteableMarginBottom),
-        mUnwriteableMarginLeft(aUnwriteableMarginLeft),
-        mUnwriteableMarginRight(aUnwriteableMarginRight) {}
+
+  explicit nsPaper(const mozilla::PaperInfo& aInfo) : mInfo(aInfo) {}
 
  private:
   ~nsPaper() = default;
-
-  nsString mName;
-  double mWidth;
-  double mHeight;
-  double mUnwriteableMarginTop;
-  double mUnwriteableMarginBottom;
-  double mUnwriteableMarginLeft;
-  double mUnwriteableMarginRight;
+  const mozilla::PaperInfo mInfo;
 };
 
+namespace mozilla {
+
+// Turns this into a JSValue by wrapping it in an nsPaper struct.
+//
+// FIXME: If using WebIDL dictionaries we'd get this for ~free...
+MOZ_MUST_USE inline bool ToJSValue(JSContext* aCx, const PaperInfo& aInfo,
+                                   JS::MutableHandleValue aValue) {
+  RefPtr<nsPaper> paper = new nsPaper(aInfo);
+  return dom::ToJSValue(aCx, paper, aValue);
+}
+
+}  // namespace mozilla
+
 #endif /* nsPaper_h__ */

widget/nsPrinter.cpp

@@ -19,9 +19,3 @@ nsPrinter::GetName(nsAString& aName) {
   aName = mName;
   return NS_OK;
 }
-
-NS_IMETHODIMP
-nsPrinter::GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) {
-  aPaperList.Assign(mPaperList);
-  return NS_OK;
-}

widget/nsPrinter.h

@@ -7,14 +7,15 @@
 #define nsPrinter_h__
 
 #include "nsPrinterBase.h"
+#include "nsPaper.h"
 #include "nsString.h"
 
 class nsPrinter final : public nsPrinterBase {
  public:
   NS_IMETHOD GetName(nsAString& aName) override;
-  NS_IMETHOD GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) override;
   bool SupportsDuplex() const final { return false; }
   bool SupportsColor() const final { return false; }
+  nsTArray<mozilla::PaperInfo> PaperList() const final { return {}; }
 
   nsPrinter() = delete;
 

widget/nsPrinterBase.cpp

@@ -5,6 +5,7 @@
 
 #include "nsPrinterBase.h"
 #include "nsPrinter.h"
+#include "nsPaper.h"
 #include "mozilla/dom/Promise.h"
 
 using namespace mozilla;
@@ -84,7 +85,14 @@ NS_IMETHODIMP nsPrinterBase::GetSupportsColor(JSContext* aCx,
                                            &nsPrinterBase::SupportsColor);
 }
 
-NS_IMPL_CYCLE_COLLECTION(nsPrinterBase, mAsyncAttributePromises, mPaperList)
+NS_IMETHODIMP nsPrinterBase::GetPaperList(JSContext* aCx,
+                                          Promise** aResultPromise) {
+  return AsyncPromiseAttributeGetter<nsTArray<PaperInfo>>(
+      aCx, aResultPromise, AsyncAttribute::PaperList,
+      &nsPrinterBase::PaperList);
+}
+
+NS_IMPL_CYCLE_COLLECTION(nsPrinterBase, mAsyncAttributePromises)
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsPrinterBase)
   NS_INTERFACE_MAP_ENTRY(nsIPrinter)

widget/nsPrinterBase.h

@@ -12,16 +12,23 @@
 #include "mozilla/EnumeratedArray.h"
 #include "mozilla/Result.h"
 
-namespace mozilla::dom {
+namespace mozilla {
+
+struct PaperInfo;
+
+namespace dom {
 class Promise;
 }
 
+}  // namespace mozilla
+
 class nsPrinterBase : public nsIPrinter {
  public:
   using Promise = mozilla::dom::Promise;
 
   NS_IMETHOD GetSupportsDuplex(JSContext*, Promise**) final;
   NS_IMETHOD GetSupportsColor(JSContext*, Promise**) final;
+  NS_IMETHOD GetPaperList(JSContext*, Promise**) final;
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_CLASS(nsPrinterBase)
@@ -34,6 +41,7 @@ class nsPrinterBase : public nsIPrinter {
   enum class AsyncAttribute {
     SupportsDuplex = 0,
     SupportsColor,
+    PaperList,
     // Just a guard.
     Last,
   };
@@ -55,9 +63,7 @@ class nsPrinterBase : public nsIPrinter {
   // which thread they run on.
   virtual bool SupportsDuplex() const = 0;
   virtual bool SupportsColor() const = 0;
-
-  // FIXME: Temporary, should probably be moved to the async attribute stuff.
-  nsTArray<RefPtr<nsIPaper>> mPaperList;
+  virtual nsTArray<mozilla::PaperInfo> PaperList() const = 0;
 
  private:
   mozilla::EnumeratedArray<AsyncAttribute, AsyncAttribute::Last,

widget/nsPrinterCUPS.cpp

@@ -4,32 +4,33 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "nsPrinterCUPS.h"
+#include "nsPaper.h"
+#include "nsPrinterBase.h"
 
-nsPrinterCUPS::nsPrinterCUPS(const nsCUPSShim& aShim, cups_dest_t* aPrinter,
-                             nsTArray<RefPtr<nsIPaper>>&& aPaperList)
+nsPrinterCUPS::nsPrinterCUPS(const nsCUPSShim& aShim, cups_dest_t* aPrinter)
     : mShim(aShim) {
   MOZ_ASSERT(aPrinter);
   MOZ_ASSERT(mShim.IsInitialized());
   DebugOnly<const int> numCopied = aShim.mCupsCopyDest(aPrinter, 0, &mPrinter);
   MOZ_ASSERT(numCopied == 1);
   mPrinterInfo = aShim.mCupsCopyDestInfo(CUPS_HTTP_DEFAULT, mPrinter);
-  mPaperList = std::move(aPaperList);
 }
 
 nsPrinterCUPS::~nsPrinterCUPS() {
   if (mPrinterInfo) {
     mShim.mCupsFreeDestInfo(mPrinterInfo);
+    mPrinterInfo = nullptr;
   }
   if (mPrinter) {
     mShim.mCupsFreeDests(1, mPrinter);
+    mPrinter = nullptr;
   }
 }
 
 // static
-already_AddRefed<nsPrinterCUPS> nsPrinterCUPS::Create(
-    const nsCUPSShim& aShim, cups_dest_t* aPrinter,
-    nsTArray<RefPtr<nsIPaper>>&& aPaperList) {
-  return do_AddRef(new nsPrinterCUPS(aShim, aPrinter, std::move(aPaperList)));
+already_AddRefed<nsPrinterCUPS> nsPrinterCUPS::Create(const nsCUPSShim& aShim,
+                                                      cups_dest_t* aPrinter) {
+  return do_AddRef(new nsPrinterCUPS(aShim, aPrinter));
 }
 
 NS_IMETHODIMP
@@ -38,12 +39,6 @@ nsPrinterCUPS::GetName(nsAString& aName) {
   return NS_OK;
 }
 
-NS_IMETHODIMP
-nsPrinterCUPS::GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) {
-  aPaperList.Assign(mPaperList);
-  return NS_OK;
-}
-
 bool nsPrinterCUPS::SupportsDuplex() const {
   return Supports(CUPS_SIDES, CUPS_SIDES_TWO_SIDED_PORTRAIT);
 }
@@ -55,3 +50,63 @@ bool nsPrinterCUPS::Supports(const char* option, const char* value) const {
   return mShim.mCupsCheckDestSupported(CUPS_HTTP_DEFAULT, mPrinter,
                                        mPrinterInfo, option, value);
 }
+
+nsTArray<mozilla::PaperInfo> nsPrinterCUPS::PaperList() const {
+  if (!mPrinterInfo) {
+    return {};
+  }
+
+  const int paperCount = mShim.mCupsGetDestMediaCount(
+      CUPS_HTTP_DEFAULT, mPrinter, mPrinterInfo, CUPS_MEDIA_FLAGS_DEFAULT);
+
+  // blocking call
+  http_t* connection = mShim.mCupsConnectDest(mPrinter, CUPS_DEST_FLAGS_NONE,
+                                              /* timeout(ms) */ 5000,
+                                              /* cancel */ nullptr,
+                                              /* resource */ nullptr,
+                                              /* resourcesize */ 0,
+                                              /* callback */ nullptr,
+                                              /* user_data */ nullptr);
+
+  if (!connection) {
+    return {};
+  }
+
+  nsTArray<mozilla::PaperInfo> paperList;
+  for (int i = 0; i < paperCount; ++i) {
+    cups_size_t info;
+    int getInfoSucceded = mShim.mCupsGetDestMediaByIndex(
+        CUPS_HTTP_DEFAULT, mPrinter, mPrinterInfo, i, CUPS_MEDIA_FLAGS_DEFAULT,
+        &info);
+
+    if (!getInfoSucceded) {
+      continue;
+    }
+
+    // localizedName is owned by mPrinterInfo.
+    // https://www.cups.org/doc/cupspm.html#cupsLocalizeDestMedia
+    const char* localizedName = mShim.mCupsLocalizeDestMedia(
+        connection, mPrinter, mPrinterInfo, CUPS_MEDIA_FLAGS_DEFAULT, &info);
+
+    if (!localizedName) {
+      continue;
+    }
+
+    // XXX Do we actually have the guarantee that this is utf-8?
+    NS_ConvertUTF8toUTF16 name(localizedName);
+    const double kPointsPerHundredthMillimeter = 0.0283465;
+
+    paperList.AppendElement(mozilla::PaperInfo{
+        std::move(name),
+        info.width * kPointsPerHundredthMillimeter,
+        info.length * kPointsPerHundredthMillimeter,
+        info.top * kPointsPerHundredthMillimeter,
+        info.right * kPointsPerHundredthMillimeter,
+        info.bottom * kPointsPerHundredthMillimeter,
+        info.left * kPointsPerHundredthMillimeter,
+    });
+  }
+
+  mShim.mHttpClose(connection);
+  return paperList;
+}

widget/nsPrinterCUPS.h

@@ -16,24 +16,20 @@
 class nsPrinterCUPS final : public nsPrinterBase {
  public:
   NS_IMETHOD GetName(nsAString& aName) override;
-  NS_IMETHOD GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) override;
   bool SupportsDuplex() const final;
   bool SupportsColor() const final;
+  nsTArray<mozilla::PaperInfo> PaperList() const final;
 
   nsPrinterCUPS() = delete;
 
   /**
    * @p aPrinter must not be null.
-   * @todo: Once CUPS-enumeration of paper sizes lands, we can remove the
-   * |aPaperList|.
    */
-  static already_AddRefed<nsPrinterCUPS> Create(
-      const nsCUPSShim& aShim, cups_dest_t* aPrinter,
-      nsTArray<RefPtr<nsIPaper>>&& aPaperList);
+  static already_AddRefed<nsPrinterCUPS> Create(const nsCUPSShim& aShim,
+                                                cups_dest_t* aPrinter);
 
  private:
-  nsPrinterCUPS(const nsCUPSShim& aShim, cups_dest_t* aPrinter,
-                nsTArray<RefPtr<nsIPaper>>&& aPaperList);
+  nsPrinterCUPS(const nsCUPSShim& aShim, cups_dest_t* aPrinter);
 
   ~nsPrinterCUPS();
 

widget/windows/moz.build

@@ -123,7 +123,6 @@ SOURCES += [
 if CONFIG['NS_PRINTING']:
     UNIFIED_SOURCES += [
         'nsDeviceContextSpecWin.cpp',
-        'nsPaperWin.cpp',
         'nsPrintDialogUtil.cpp',
         'nsPrintDialogWin.cpp',
         'nsPrinterWin.cpp',

widget/windows/nsPaperWin.cpp

@@ -1,100 +0,0 @@
-/* -*- Mode: C++; tab-width: 4; 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 "nsPaperWin.h"
-
-#include "nsWindowsHelpers.h"
-#include "WinUtils.h"
-
-using namespace mozilla::widget;
-
-static const wchar_t kDriverName[] = L"WINSPOOL";
-
-nsPaperWin::nsPaperWin(WORD aId, const nsAString& aName,
-                       const nsAString& aPrinterName, double aWidth,
-                       double aHeight)
-    : mId(aId),
-      mName(aName),
-      mPrinterName(aPrinterName),
-      mSize(aWidth, aHeight) {}
-
-NS_IMPL_ISUPPORTS(nsPaperWin, nsIPaper);
-
-void nsPaperWin::EnsureUnwriteableMargin() {
-  if (mUnwriteableMarginRetrieved) {
-    return;
-  }
-
-  // We need a DEVMODE to set the paper size on the context.
-  DEVMODEW devmode = {};
-  devmode.dmSize = sizeof(DEVMODEW);
-  devmode.dmFields = DM_PAPERSIZE;
-  devmode.dmPaperSize = mId;
-
-  // Create an information context, so that we can get margin information.
-  // Note: this blocking call interacts with the driver and can be slow.
-  nsAutoHDC printerDc(
-      ::CreateICW(kDriverName, mPrinterName.get(), nullptr, &devmode));
-
-  MarginDouble unWrtMarginInInches =
-      WinUtils::GetUnwriteableMarginsForDeviceInInches(printerDc);
-  mUnwriteableMargin.SizeTo(unWrtMarginInInches.top * POINTS_PER_INCH_FLOAT,
-                            unWrtMarginInInches.right * POINTS_PER_INCH_FLOAT,
-                            unWrtMarginInInches.bottom * POINTS_PER_INCH_FLOAT,
-                            unWrtMarginInInches.left * POINTS_PER_INCH_FLOAT);
-  mUnwriteableMarginRetrieved = true;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetName(nsAString& aName) {
-  aName = mName;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetWidth(double* aWidth) {
-  MOZ_ASSERT(aWidth);
-  *aWidth = mSize.Width();
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetHeight(double* aHeight) {
-  MOZ_ASSERT(aHeight);
-  *aHeight = mSize.Height();
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetUnwriteableMarginTop(double* aUnwriteableMarginTop) {
-  MOZ_ASSERT(aUnwriteableMarginTop);
-  EnsureUnwriteableMargin();
-  *aUnwriteableMarginTop = mUnwriteableMargin.top;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetUnwriteableMarginBottom(double* aUnwriteableMarginBottom) {
-  MOZ_ASSERT(aUnwriteableMarginBottom);
-  EnsureUnwriteableMargin();
-  *aUnwriteableMarginBottom = mUnwriteableMargin.bottom;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetUnwriteableMarginLeft(double* aUnwriteableMarginLeft) {
-  MOZ_ASSERT(aUnwriteableMarginLeft);
-  EnsureUnwriteableMargin();
-  *aUnwriteableMarginLeft = mUnwriteableMargin.left;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPaperWin::GetUnwriteableMarginRight(double* aUnwriteableMarginRight) {
-  MOZ_ASSERT(aUnwriteableMarginRight);
-  EnsureUnwriteableMargin();
-  *aUnwriteableMarginRight = mUnwriteableMargin.right;
-  return NS_OK;
-}

widget/windows/nsPaperWin.h

@@ -1,41 +0,0 @@
-/* -*- Mode: C++; tab-width: 4; 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/. */
-
-#ifndef nsPaperWin_h_
-#define nsPaperWin_h_
-
-#include "nsIPaper.h"
-
-#include <wtypes.h>
-
-#include "mozilla/gfx/Rect.h"
-#include "nsISupportsImpl.h"
-#include "nsString.h"
-
-class nsPaperWin final : public nsIPaper {
- public:
-  NS_DECL_ISUPPORTS
-  NS_DECL_NSIPAPER
-  nsPaperWin() = delete;
-  nsPaperWin(WORD aId, const nsAString& aName, const nsAString& aPrinterName,
-             double aWidth, double aHeight);
-
- private:
-  ~nsPaperWin() = default;
-
-  void EnsureUnwriteableMargin();
-
-  using SizeDouble = mozilla::gfx::SizeDouble;
-  using MarginDouble = mozilla::gfx::MarginDouble;
-
-  WORD mId;
-  nsString mName;
-  nsString mPrinterName;
-  SizeDouble mSize;
-  MarginDouble mUnwriteableMargin;
-  bool mUnwriteableMarginRetrieved = false;
-};
-
-#endif  // nsPaperWin_h_

widget/windows/nsPrinterWin.cpp

@@ -9,7 +9,7 @@
 #include <windows.h>
 
 #include "mozilla/Array.h"
-#include "nsPaperWin.h"
+#include "nsPaper.h"
 
 using namespace mozilla;
 using namespace mozilla::gfx;
@@ -62,11 +62,23 @@ static nsTArray<T> GetDeviceCapabilityArray(const LPWSTR aPrinterName,
   return caps;
 }
 
-nsresult nsPrinterWin::EnsurePaperList() {
-  if (!mPaperList.IsEmpty()) {
-    return NS_OK;
-  }
+NS_IMETHODIMP
+nsPrinterWin::GetName(nsAString& aName) {
+  aName.Assign(mName);
+  return NS_OK;
+}
 
+bool nsPrinterWin::SupportsDuplex() const {
+  return ::DeviceCapabilitiesW(mName.get(), nullptr, DC_DUPLEX, nullptr,
+                               nullptr) == 1;
+}
+
+bool nsPrinterWin::SupportsColor() const {
+  return ::DeviceCapabilitiesW(mName.get(), nullptr, DC_COLORDEVICE, nullptr,
+                               nullptr) == 1;
+}
+
+nsTArray<mozilla::PaperInfo> nsPrinterWin::PaperList() const {
   // Paper names are returned in 64 long character buffers.
   auto paperNames =
       GetDeviceCapabilityArray<Array<wchar_t, 64>>(mName.get(), DC_PAPERNAMES);
@@ -81,10 +93,12 @@ nsresult nsPrinterWin::EnsurePaperList() {
   // Check that we have papers and that the array lengths match.
   if (!paperNames.Length() || paperNames.Length() != paperIds.Length() ||
       paperNames.Length() != paperSizes.Length()) {
-    return NS_ERROR_UNEXPECTED;
+    return {};
   }
 
-  mPaperList.SetCapacity(paperNames.Length());
+  static const wchar_t kDriverName[] = L"WINSPOOL";
+  nsTArray<mozilla::PaperInfo> paperList;
+  paperList.SetCapacity(paperNames.Length());
   for (size_t i = 0; i < paperNames.Length(); ++i) {
     // Paper names are null terminated unless they are 64 characters long.
     auto firstNull =
@@ -98,37 +112,34 @@ nsresult nsPrinterWin::EnsurePaperList() {
       continue;
     }
 
-    nsAutoString paperName(paperNames[i].cbegin(), nameLength);
-    mPaperList.AppendElement(
-        new nsPaperWin(paperIds[i], paperName, mName, width, height));
+    WORD id = paperIds[i];
+
+    // Now get the margin info.
+    // We need a DEVMODE to set the paper size on the context.
+    DEVMODEW devmode = {};
+    devmode.dmSize = sizeof(DEVMODEW);
+    devmode.dmFields = DM_PAPERSIZE;
+    devmode.dmPaperSize = id;
+
+    // Create an information context, so that we can get margin information.
+    // Note: this blocking call interacts with the driver and can be slow.
+    nsAutoHDC printerDc(
+        ::CreateICW(kDriverName, mName.get(), nullptr, &devmode));
+
+    auto marginInInches =
+        WinUtils::GetUnwriteableMarginsForDeviceInInches(printerDc);
+
+    nsDependentSubstring name(paperNames[i].cbegin(), nameLength);
+    paperList.AppendElement(mozilla::PaperInfo{
+        nsString(name),
+        width,
+        height,
+        marginInInches.top * POINTS_PER_INCH_FLOAT,
+        marginInInches.right * POINTS_PER_INCH_FLOAT,
+        marginInInches.bottom * POINTS_PER_INCH_FLOAT,
+        marginInInches.left * POINTS_PER_INCH_FLOAT,
+    });
   }
 
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPrinterWin::GetName(nsAString& aName) {
-  aName.Assign(mName);
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsPrinterWin::GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) {
-  nsresult rv = EnsurePaperList();
-  if (NS_WARN_IF(NS_FAILED(rv))) {
-    return rv;
-  }
-
-  aPaperList.Assign(mPaperList);
-  return NS_OK;
-}
-
-bool nsPrinterWin::SupportsDuplex() const {
-  return ::DeviceCapabilitiesW(mName.get(), nullptr, DC_DUPLEX, nullptr,
-                               nullptr) == 1;
-}
-
-bool nsPrinterWin::SupportsColor() const {
-  return ::DeviceCapabilitiesW(mName.get(), nullptr, DC_COLORDEVICE, nullptr,
-                               nullptr) == 1;
+  return paperList;
 }

widget/windows/nsPrinterWin.h

@@ -11,10 +11,10 @@
 class nsPrinterWin final : public nsPrinterBase {
  public:
   NS_IMETHOD GetName(nsAString& aName) override;
-  NS_IMETHOD GetPaperList(nsTArray<RefPtr<nsIPaper>>& aPaperList) override;
 
   bool SupportsDuplex() const final;
   bool SupportsColor() const final;
+  nsTArray<mozilla::PaperInfo> PaperList() const final;
 
   nsPrinterWin() = delete;
   static already_AddRefed<nsPrinterWin> Create(const nsAString& aName);