electron/shell/browser/electron_browser_main_parts...

144 lines
4.7 KiB
C++

// Copyright (c) 2022 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#include "shell/browser/electron_browser_main_parts.h"
#include <string_view>
#include "base/command_line.h"
#include "base/environment.h"
#include "ui/base/ozone_buildflags.h"
#include "ui/ozone/public/ozone_switches.h"
#if BUILDFLAG(IS_OZONE_WAYLAND)
#include "base/files/file_path.h"
#include "base/files/file_util.h"
#include "base/nix/xdg_util.h"
#include "shell/common/thread_restrictions.h"
#endif
namespace electron {
namespace {
constexpr std::string_view kElectronOzonePlatformHint{
"ELECTRON_OZONE_PLATFORM_HINT"};
#if BUILDFLAG(IS_OZONE_WAYLAND)
constexpr char kPlatformWayland[] = "wayland";
bool HasWaylandDisplay(base::Environment* env) {
std::string wayland_display;
const bool has_wayland_display =
env->GetVar("WAYLAND_DISPLAY", &wayland_display) &&
!wayland_display.empty();
if (has_wayland_display)
return true;
std::string xdg_runtime_dir;
const bool has_xdg_runtime_dir =
env->GetVar("XDG_RUNTIME_DIR", &xdg_runtime_dir) &&
!xdg_runtime_dir.empty();
if (has_xdg_runtime_dir) {
auto wayland_server_pipe =
base::FilePath(xdg_runtime_dir).Append("wayland-0");
// Normally, this should happen exactly once, at the startup of the main
// process.
electron::ScopedAllowBlockingForElectron allow_blocking;
return base::PathExists(wayland_server_pipe);
}
return false;
}
#endif // BUILDFLAG(IS_OZONE_WAYLAND)
#if BUILDFLAG(IS_OZONE_X11)
constexpr char kPlatformX11[] = "x11";
#endif
// Evaluates the environment and returns the effective platform name for the
// given |ozone_platform_hint|.
// For the "auto" value, returns "wayland" if the XDG session type is "wayland",
// "x11" otherwise.
// For the "wayland" value, checks if the Wayland server is available, and
// returns "x11" if it is not.
// See https://crbug.com/1246928.
std::string MaybeFixPlatformName(const std::string& ozone_platform_hint) {
#if BUILDFLAG(IS_OZONE_WAYLAND)
// Wayland is selected if both conditions below are true:
// 1. The user selected either 'wayland' or 'auto'.
// 2. The XDG session type is 'wayland', OR the user has selected 'wayland'
// explicitly and a Wayland server is running.
// Otherwise, fall back to X11.
if (ozone_platform_hint == kPlatformWayland ||
ozone_platform_hint == "auto") {
auto env(base::Environment::Create());
std::string xdg_session_type;
const bool has_xdg_session_type =
env->GetVar(base::nix::kXdgSessionTypeEnvVar, &xdg_session_type) &&
!xdg_session_type.empty();
if ((has_xdg_session_type && xdg_session_type == "wayland") ||
(ozone_platform_hint == kPlatformWayland &&
HasWaylandDisplay(env.get()))) {
return kPlatformWayland;
}
}
#endif // BUILDFLAG(IS_OZONE_WAYLAND)
#if BUILDFLAG(IS_OZONE_X11)
if (ozone_platform_hint == kPlatformX11) {
return kPlatformX11;
}
#if BUILDFLAG(IS_OZONE_WAYLAND)
if (ozone_platform_hint == kPlatformWayland ||
ozone_platform_hint == "auto") {
// We are here if:
// - The binary has both X11 and Wayland backends.
// - The user wanted Wayland but that did not work, otherwise it would have
// been returned above.
if (ozone_platform_hint == kPlatformWayland) {
LOG(WARNING) << "No Wayland server is available. Falling back to X11.";
} else {
LOG(WARNING) << "This is not a Wayland session. Falling back to X11. "
"If you need to run Chrome on Wayland using some "
"embedded compositor, e. g., Weston, please specify "
"Wayland as your preferred Ozone platform, or use "
"--ozone-platform=wayland.";
}
return kPlatformX11;
}
#endif // BUILDFLAG(IS_OZONE_WAYLAND)
#endif // BUILDFLAG(OZONE_PLATFORM_X11)
return ozone_platform_hint;
}
} // namespace
void ElectronBrowserMainParts::DetectOzonePlatform() {
auto const env = base::Environment::Create();
auto* const command_line = base::CommandLine::ForCurrentProcess();
if (!command_line->HasSwitch(switches::kOzonePlatform)) {
auto ozone_platform_hint =
command_line->GetSwitchValueASCII(switches::kOzonePlatformHint);
if (ozone_platform_hint.empty()) {
env->GetVar(kElectronOzonePlatformHint, &ozone_platform_hint);
}
if (!ozone_platform_hint.empty()) {
command_line->AppendSwitchASCII(
switches::kOzonePlatform, MaybeFixPlatformName(ozone_platform_hint));
}
}
std::string desktop_startup_id;
if (env->GetVar("DESKTOP_STARTUP_ID", &desktop_startup_id))
command_line->AppendSwitchASCII("desktop-startup-id", desktop_startup_id);
}
} // namespace electron