Bug 1818418 - Use reg.exe to implement MSIX 1-click set-to-default. r=mhughes

This approach uses `reg.exe` to delete and recreate the relevant HKCU
registry key-value pairs.

Differential Revision: https://phabricator.services.mozilla.com/D170717

Author: ncalexan

browser/components/shell/WindowsUserChoice.cpp

@@ -20,11 +20,13 @@
  */
 
 #include <windows.h>
+#include <appmodel.h>  // for GetPackageFamilyName
 #include <sddl.h>      // for ConvertSidToStringSidW
 #include <wincrypt.h>  // for CryptoAPI base64
 #include <bcrypt.h>    // for CNG MD5
 #include <winternl.h>  // for NT_SUCCESS()
 
+#include "nsDebug.h"
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/UniquePtr.h"
 #include "nsWindowsHelpers.h"
@@ -420,3 +422,53 @@ bool CheckProgIDExists(const wchar_t* aProgID) {
   ::RegCloseKey(key);
   return true;
 }
+
+nsresult GetMsixProgId(const wchar_t* assoc, UniquePtr<wchar_t[]>& aProgId) {
+  // Retrieve the registry path to the package from registry path:
+  // clang-format off
+  // HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppModel\Repository\Packages\[Package Full Name]\App\Capabilities\[FileAssociations | URLAssociations]\[File | URL]
+  // clang-format on
+
+  UINT32 pfnLen = 0;
+  LONG rv = GetCurrentPackageFullName(&pfnLen, nullptr);
+  NS_ENSURE_TRUE(rv != APPMODEL_ERROR_NO_PACKAGE, NS_ERROR_FAILURE);
+
+  auto pfn = mozilla::MakeUnique<wchar_t[]>(pfnLen);
+  rv = GetCurrentPackageFullName(&pfnLen, pfn.get());
+  NS_ENSURE_TRUE(rv == ERROR_SUCCESS, NS_ERROR_FAILURE);
+
+  const wchar_t* assocSuffix;
+  if (assoc[0] == L'.') {
+    // File association.
+    assocSuffix = LR"(App\Capabilities\FileAssociations)";
+  } else {
+    // URL association.
+    assocSuffix = LR"(App\Capabilities\URLAssociations)";
+  }
+
+  const wchar_t* assocPathFmt =
+      LR"(Local Settings\Software\Microsoft\Windows\CurrentVersion\AppModel\Repository\Packages\%s\%s)";
+  int assocPathLen = _scwprintf(assocPathFmt, pfn.get(), assocSuffix);
+  assocPathLen += 1;  // _scwprintf does not include the terminator
+
+  auto assocPath = MakeUnique<wchar_t[]>(assocPathLen);
+  _snwprintf_s(assocPath.get(), assocPathLen, _TRUNCATE, assocPathFmt,
+               pfn.get(), assocSuffix);
+
+  LSTATUS ls;
+
+  // Retrieve the package association's ProgID, always in the form `AppX[32 hash
+  // characters]`.
+  const size_t appxProgIdLen = 37;
+  auto progId = MakeUnique<wchar_t[]>(appxProgIdLen);
+  DWORD progIdLen = appxProgIdLen * sizeof(wchar_t);
+  ls = ::RegGetValueW(HKEY_CLASSES_ROOT, assocPath.get(), assoc, RRF_RT_REG_SZ,
+                      nullptr, (LPBYTE)progId.get(), &progIdLen);
+  if (ls != ERROR_SUCCESS) {
+    return NS_ERROR_WDBA_NO_PROGID;
+  }
+
+  aProgId.swap(progId);
+
+  return NS_OK;
+}

browser/components/shell/WindowsUserChoice.h

@@ -8,6 +8,7 @@
 
 #include <windows.h>
 
+#include "ErrorList.h"  // for nsresult
 #include "mozilla/UniquePtr.h"
 
 /*
@@ -100,4 +101,17 @@ mozilla::UniquePtr<wchar_t[]> FormatProgID(const wchar_t* aProgIDBase,
  */
 bool CheckProgIDExists(const wchar_t* aProgID);
 
+/*
+ * Get the ProgID registered by Windows for the given association.
+ *
+ * The MSIX `AppManifest.xml` declares supported protocols and file
+ * type associations.  Upon installation, Windows generates
+ * corresponding ProgIDs for them, of the form `AppX*`.  This function
+ * retrieves those generated ProgIDs (from the Windows registry).
+ *
+ * @return ProgID.
+ */
+nsresult GetMsixProgId(const wchar_t* assoc,
+                       mozilla::UniquePtr<wchar_t[]>& aProgId);
+
 #endif  // SHELL_WINDOWSUSERCHOICE_H__

browser/components/shell/nsWindowsShellService.cpp

@@ -300,10 +300,41 @@ nsWindowsShellService::CheckAllProgIDsExist(bool* aResult) {
   if (!mozilla::widget::WinTaskbar::GetAppUserModelID(aumid)) {
     return NS_OK;
   }
-  *aResult =
-      CheckProgIDExists(FormatProgID(L"FirefoxURL", aumid.get()).get()) &&
-      CheckProgIDExists(FormatProgID(L"FirefoxHTML", aumid.get()).get()) &&
-      CheckProgIDExists(FormatProgID(L"FirefoxPDF", aumid.get()).get());
+
+  if (widget::WinUtils::HasPackageIdentity()) {
+    UniquePtr<wchar_t[]> extraProgID;
+    nsresult rv;
+    bool result = true;
+
+    // "FirefoxURL".
+    rv = GetMsixProgId(L"https", extraProgID);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+    result = result && CheckProgIDExists(extraProgID.get());
+
+    // "FirefoxHTML".
+    rv = GetMsixProgId(L".htm", extraProgID);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+    result = result && CheckProgIDExists(extraProgID.get());
+
+    // "FirefoxPDF".
+    rv = GetMsixProgId(L".pdf", extraProgID);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+    result = result && CheckProgIDExists(extraProgID.get());
+
+    *aResult = result;
+  } else {
+    *aResult =
+        CheckProgIDExists(FormatProgID(L"FirefoxURL", aumid.get()).get()) &&
+        CheckProgIDExists(FormatProgID(L"FirefoxHTML", aumid.get()).get()) &&
+        CheckProgIDExists(FormatProgID(L"FirefoxPDF", aumid.get()).get());
+  }
+
   return NS_OK;
 }
 

python/mozbuild/mozbuild/repackaging/msix.py

@@ -198,9 +198,8 @@ def get_branding(use_official, topsrcdir, build_app, finder, log=None):
     conf_vars = mozpath.join(topsrcdir, build_app, "confvars.sh")
 
     def conf_vars_value(key):
-        lines = open(conf_vars).readlines()
+        lines = [line.strip() for line in open(conf_vars).readlines()]
         for line in lines:
-            line = line.strip()
             if line and line[0] == "#":
                 continue
             if key not in line:
@@ -833,7 +832,7 @@ def powershell(argstring, check=True):
         else:
             thumbprint = None
 
-        if not thumbprint:
+        if force or not thumbprint:
             thumbprint = (
                 powershell(
                     (