gecko-dev/mozglue/misc/WindowsDpiInitialization.h
Chris Martin 38d538c966 Bug 1701770 - Defer Windows DPI Awareness from load time to run time r=bobowen,aklotz
Currently, we set DPI awareness in the manifest files for firefox.exe.

Unfortunately, that causes DPI-related Win32k calls when user32.dll
is loaded.

This changes things to wait until we are sure we're not running in a
Win32k Lockdown Content Process before we attempt to initialize DPI scaling.

Differential Revision: https://phabricator.services.mozilla.com/D116433
2021-06-21 13:50:31 +00:00

55 lines
2.2 KiB
C++

/* -*- 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 MOZILLA_MOZGLUE_MISC_WINDOWSDPIINITIALIZATION_H_
#define MOZILLA_MOZGLUE_MISC_WINDOWSDPIINITIALIZATION_H_
#include "mozilla/Types.h"
namespace mozilla {
// The result codes that may be returned from WindowsDpiInitialization()
enum class WindowsDpiInitializationResult : uint32_t {
Success,
FindSetProcessDpiAwarenessContextFailed,
SetProcessDpiAwarenessContextFailed,
FindSetProcessDpiAwarenessFailed,
SetProcessDpiAwarenessFailed,
SetProcessDPIAwareFailed,
};
// Get a string representation of any WindowsDpiInitializationResult value
inline const char* WindowsDpiInitializationResultString(
WindowsDpiInitializationResult result) {
switch (result) {
case WindowsDpiInitializationResult::Success:
return "Success";
case WindowsDpiInitializationResult::
FindSetProcessDpiAwarenessContextFailed:
return "Failed to find SetProcessDpiAwarenessContext";
case WindowsDpiInitializationResult::SetProcessDpiAwarenessContextFailed:
return "SetProcessDpiAwarenessContext failed";
case WindowsDpiInitializationResult::FindSetProcessDpiAwarenessFailed:
return "Failed to find SetProcessDpiAwareness";
case WindowsDpiInitializationResult::SetProcessDpiAwarenessFailed:
return "SetProcessDpiAwareness failed";
case WindowsDpiInitializationResult::SetProcessDPIAwareFailed:
return "SetProcessDPIAware failed";
default:
return "Unknown result";
}
}
// Initialize DPI awareness to the best available for the current OS
// According to MSDN, this will be:
// Per-Monitor V2 for Windows 10 Creators Update (1703) and later
// Per-Monitor V1 for Windows 8.1 and later
// System DPI for Vista and later (we don't support anything older)
// https://docs.microsoft.com/en-us/windows/win32/hidpi/high-dpi-desktop-application-development-on-windows
MFBT_API WindowsDpiInitializationResult WindowsDpiInitialization();
} // namespace mozilla
#endif // MOZILLA_MOZGLUE_MISC_WINDOWSDPIINITIALIZATION_H_