1 files changed, 75 insertions, 0 deletions
diff --git a/toolkit/mozapps/defaultagent/DefaultPDF.cpp b/toolkit/mozapps/defaultagent/DefaultPDF.cpp
new file mode 100644
index 0000000000..27dbb3480c
--- /dev/null
+++ b/toolkit/mozapps/defaultagent/DefaultPDF.cpp
@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "DefaultPDF.h"
+
+#include <string>
+
+#include <shlobj.h>
+#include <winerror.h>
+
+#include "EventLog.h"
+#include "UtfConvert.h"
+
+#include "mozilla/Buffer.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/WinHeaderOnlyUtils.h"
+
+using PdfResult = mozilla::WindowsErrorResult<std::string>;
+
+static PdfResult GetDefaultPdf() {
+  RefPtr<IApplicationAssociationRegistration> pAAR;
+  HRESULT hr = CoCreateInstance(
+      CLSID_ApplicationAssociationRegistration, nullptr, CLSCTX_INPROC,
+      IID_IApplicationAssociationRegistration, getter_AddRefs(pAAR));
+  if (FAILED(hr)) {
+    LOG_ERROR(hr);
+    return PdfResult(mozilla::WindowsError::FromHResult(hr));
+  }
+
+  mozilla::UniquePtr<wchar_t, mozilla::CoTaskMemFreeDeleter> registeredApp;
+  {
+    wchar_t* rawRegisteredApp;
+    hr = pAAR->QueryCurrentDefault(L".pdf", AT_FILEEXTENSION, AL_EFFECTIVE,
+                                   &rawRegisteredApp);
+    if (FAILED(hr)) {
+      LOG_ERROR(hr);
+      return PdfResult(mozilla::WindowsError::FromHResult(hr));
+    }
+    registeredApp = mozilla::UniquePtr<wchar_t, mozilla::CoTaskMemFreeDeleter>{
+        rawRegisteredApp};
+  }
+
+  // Get the application Friendly Name associated to the found ProgID. This is
+  // sized to be larger than any observed or expected friendly names. Long
+  // friendly names tend to be in the form `[Company] [Viewer] [Variant]`
+  DWORD friendlyNameLen = 0;
+  hr = AssocQueryStringW(ASSOCF_NONE, ASSOCSTR_FRIENDLYAPPNAME,
+                         registeredApp.get(), nullptr, nullptr,
+                         &friendlyNameLen);
+  if (FAILED(hr)) {
+    LOG_ERROR(hr);
+    return PdfResult(mozilla::WindowsError::FromHResult(hr));
+  }
+
+  mozilla::Buffer<wchar_t> friendlyNameBuffer(friendlyNameLen);
+  hr = AssocQueryStringW(ASSOCF_NONE, ASSOCSTR_FRIENDLYAPPNAME,
+                         registeredApp.get(), nullptr,
+                         friendlyNameBuffer.Elements(), &friendlyNameLen);
+  if (FAILED(hr)) {
+    LOG_ERROR(hr);
+    return PdfResult(mozilla::WindowsError::FromHResult(hr));
+  }
+
+  return Utf16ToUtf8(friendlyNameBuffer.Elements());
+}
+
+DefaultPdfResult GetDefaultPdfInfo() {
+  DefaultPdfInfo pdfInfo;
+  MOZ_TRY_VAR(pdfInfo.currentDefaultPdf, GetDefaultPdf());
+
+  return pdfInfo;
+}