waybar/src/modules/backlight.cpp
Robert Günzler 0f8c156f24
Lift reverse-scrolling option into AModule
The option is generally useful when scrolling is used, when configuring
input devices to use "natural scroll direction".
Both backlight and pulseaudio were using different implementations, this
unifies and documents them.

Signed-off-by: Robert Günzler <r@gnzler.io>
2023-06-12 14:08:18 +09:00

350 lines
12 KiB
C++

#include "modules/backlight.hpp"
#include <fmt/format.h>
#include <libudev.h>
#include <sys/epoll.h>
#include <unistd.h>
#include <algorithm>
#include <chrono>
#include <memory>
namespace {
class FileDescriptor {
public:
explicit FileDescriptor(int fd) : fd_(fd) {}
FileDescriptor(const FileDescriptor &other) = delete;
FileDescriptor(FileDescriptor &&other) noexcept = delete;
FileDescriptor &operator=(const FileDescriptor &other) = delete;
FileDescriptor &operator=(FileDescriptor &&other) noexcept = delete;
~FileDescriptor() {
if (fd_ != -1) {
if (close(fd_) != 0) {
fmt::print(stderr, "Failed to close fd: {}\n", errno);
}
}
}
int get() const { return fd_; }
private:
int fd_;
};
struct UdevDeleter {
void operator()(udev *ptr) { udev_unref(ptr); }
};
struct UdevDeviceDeleter {
void operator()(udev_device *ptr) { udev_device_unref(ptr); }
};
struct UdevEnumerateDeleter {
void operator()(udev_enumerate *ptr) { udev_enumerate_unref(ptr); }
};
struct UdevMonitorDeleter {
void operator()(udev_monitor *ptr) { udev_monitor_unref(ptr); }
};
void check_eq(int rc, int expected, const char *message = "eq, rc was: ") {
if (rc != expected) {
throw std::runtime_error(fmt::format(fmt::runtime(message), rc));
}
}
void check_neq(int rc, int bad_rc, const char *message = "neq, rc was: ") {
if (rc == bad_rc) {
throw std::runtime_error(fmt::format(fmt::runtime(message), rc));
}
}
void check0(int rc, const char *message = "rc wasn't 0") { check_eq(rc, 0, message); }
void check_gte(int rc, int gte, const char *message = "rc was: ") {
if (rc < gte) {
throw std::runtime_error(fmt::format(fmt::runtime(message), rc));
}
}
void check_nn(const void *ptr, const char *message = "ptr was null") {
if (ptr == nullptr) {
throw std::runtime_error(message);
}
}
} // namespace
waybar::modules::Backlight::BacklightDev::BacklightDev(std::string name, int actual, int max,
bool powered)
: name_(std::move(name)), actual_(actual), max_(max), powered_(powered) {}
std::string_view waybar::modules::Backlight::BacklightDev::name() const { return name_; }
int waybar::modules::Backlight::BacklightDev::get_actual() const { return actual_; }
void waybar::modules::Backlight::BacklightDev::set_actual(int actual) { actual_ = actual; }
int waybar::modules::Backlight::BacklightDev::get_max() const { return max_; }
void waybar::modules::Backlight::BacklightDev::set_max(int max) { max_ = max; }
bool waybar::modules::Backlight::BacklightDev::get_powered() const { return powered_; }
void waybar::modules::Backlight::BacklightDev::set_powered(bool powered) { powered_ = powered; }
waybar::modules::Backlight::Backlight(const std::string &id, const Json::Value &config)
: ALabel(config, "backlight", id, "{percent}%", 2),
preferred_device_(config["device"].isString() ? config["device"].asString() : "") {
// Get initial state
{
std::unique_ptr<udev, UdevDeleter> udev_check{udev_new()};
check_nn(udev_check.get(), "Udev check new failed");
enumerate_devices(devices_.begin(), devices_.end(), std::back_inserter(devices_),
udev_check.get());
if (devices_.empty()) {
throw std::runtime_error("No backlight found");
}
dp.emit();
}
// Set up scroll handler
event_box_.add_events(Gdk::SCROLL_MASK | Gdk::SMOOTH_SCROLL_MASK);
event_box_.signal_scroll_event().connect(sigc::mem_fun(*this, &Backlight::handleScroll));
// Connect to the login interface
login_proxy_ = Gio::DBus::Proxy::create_for_bus_sync(
Gio::DBus::BusType::BUS_TYPE_SYSTEM, "org.freedesktop.login1",
"/org/freedesktop/login1/session/self", "org.freedesktop.login1.Session");
udev_thread_ = [this] {
std::unique_ptr<udev, UdevDeleter> udev{udev_new()};
check_nn(udev.get(), "Udev new failed");
std::unique_ptr<udev_monitor, UdevMonitorDeleter> mon{
udev_monitor_new_from_netlink(udev.get(), "udev")};
check_nn(mon.get(), "udev monitor new failed");
check_gte(udev_monitor_filter_add_match_subsystem_devtype(mon.get(), "backlight", nullptr), 0,
"udev failed to add monitor filter: ");
udev_monitor_enable_receiving(mon.get());
auto udev_fd = udev_monitor_get_fd(mon.get());
auto epoll_fd = FileDescriptor{epoll_create1(EPOLL_CLOEXEC)};
check_neq(epoll_fd.get(), -1, "epoll init failed: ");
epoll_event ctl_event{};
ctl_event.events = EPOLLIN;
ctl_event.data.fd = udev_fd;
check0(epoll_ctl(epoll_fd.get(), EPOLL_CTL_ADD, ctl_event.data.fd, &ctl_event),
"epoll_ctl failed: {}");
epoll_event events[EPOLL_MAX_EVENTS];
while (udev_thread_.isRunning()) {
const int event_count = epoll_wait(epoll_fd.get(), events, EPOLL_MAX_EVENTS,
std::chrono::milliseconds{interval_}.count());
if (!udev_thread_.isRunning()) {
break;
}
decltype(devices_) devices;
{
std::scoped_lock<std::mutex> lock(udev_thread_mutex_);
devices = devices_;
}
for (int i = 0; i < event_count; ++i) {
const auto &event = events[i];
check_eq(event.data.fd, udev_fd, "unexpected udev fd");
std::unique_ptr<udev_device, UdevDeviceDeleter> dev{udev_monitor_receive_device(mon.get())};
check_nn(dev.get(), "epoll dev was null");
upsert_device(devices.begin(), devices.end(), std::back_inserter(devices), dev.get());
}
// Refresh state if timed out
if (event_count == 0) {
enumerate_devices(devices.begin(), devices.end(), std::back_inserter(devices), udev.get());
}
{
std::scoped_lock<std::mutex> lock(udev_thread_mutex_);
devices_ = devices;
}
dp.emit();
}
};
}
waybar::modules::Backlight::~Backlight() = default;
auto waybar::modules::Backlight::update() -> void {
decltype(devices_) devices;
{
std::scoped_lock<std::mutex> lock(udev_thread_mutex_);
devices = devices_;
}
const auto best = best_device(devices.cbegin(), devices.cend(), preferred_device_);
if (best != nullptr) {
if (previous_best_.has_value() && previous_best_.value() == *best &&
!previous_format_.empty() && previous_format_ == format_) {
return;
}
if (best->get_powered()) {
event_box_.show();
const uint8_t percent =
best->get_max() == 0 ? 100 : round(best->get_actual() * 100.0f / best->get_max());
std::string desc =
fmt::format(fmt::runtime(format_), fmt::arg("percent", std::to_string(percent)),
fmt::arg("icon", getIcon(percent)));
label_.set_markup(desc);
getState(percent);
if (tooltipEnabled()) {
std::string tooltip_format;
if (config_["tooltip-format"].isString()) {
tooltip_format = config_["tooltip-format"].asString();
}
if (!tooltip_format.empty()) {
label_.set_tooltip_text(fmt::format(fmt::runtime(tooltip_format),
fmt::arg("percent", std::to_string(percent)),
fmt::arg("icon", getIcon(percent))));
} else {
label_.set_tooltip_text(desc);
}
}
} else {
event_box_.hide();
}
} else {
if (!previous_best_.has_value()) {
return;
}
label_.set_markup("");
}
previous_best_ = best == nullptr ? std::nullopt : std::optional{*best};
previous_format_ = format_;
// Call parent update
ALabel::update();
}
template <class ForwardIt>
const waybar::modules::Backlight::BacklightDev *waybar::modules::Backlight::best_device(
ForwardIt first, ForwardIt last, std::string_view preferred_device) {
const auto found = std::find_if(
first, last, [preferred_device](const auto &dev) { return dev.name() == preferred_device; });
if (found != last) {
return &(*found);
}
const auto max = std::max_element(
first, last, [](const auto &l, const auto &r) { return l.get_max() < r.get_max(); });
return max == last ? nullptr : &(*max);
}
template <class ForwardIt, class Inserter>
void waybar::modules::Backlight::upsert_device(ForwardIt first, ForwardIt last, Inserter inserter,
udev_device *dev) {
const char *name = udev_device_get_sysname(dev);
check_nn(name);
const char *actual_brightness_attr =
strncmp(name, "amdgpu_bl", 9) == 0 ? "brightness" : "actual_brightness";
const char *actual = udev_device_get_sysattr_value(dev, actual_brightness_attr);
const char *max = udev_device_get_sysattr_value(dev, "max_brightness");
const char *power = udev_device_get_sysattr_value(dev, "bl_power");
auto found =
std::find_if(first, last, [name](const auto &device) { return device.name() == name; });
if (found != last) {
if (actual != nullptr) {
found->set_actual(std::stoi(actual));
}
if (max != nullptr) {
found->set_max(std::stoi(max));
}
if (power != nullptr) {
found->set_powered(std::stoi(power) == 0);
}
} else {
const int actual_int = actual == nullptr ? 0 : std::stoi(actual);
const int max_int = max == nullptr ? 0 : std::stoi(max);
const bool power_bool = power == nullptr ? true : std::stoi(power) == 0;
*inserter = BacklightDev{name, actual_int, max_int, power_bool};
++inserter;
}
}
template <class ForwardIt, class Inserter>
void waybar::modules::Backlight::enumerate_devices(ForwardIt first, ForwardIt last,
Inserter inserter, udev *udev) {
std::unique_ptr<udev_enumerate, UdevEnumerateDeleter> enumerate{udev_enumerate_new(udev)};
udev_enumerate_add_match_subsystem(enumerate.get(), "backlight");
udev_enumerate_scan_devices(enumerate.get());
udev_list_entry *enum_devices = udev_enumerate_get_list_entry(enumerate.get());
udev_list_entry *dev_list_entry;
udev_list_entry_foreach(dev_list_entry, enum_devices) {
const char *path = udev_list_entry_get_name(dev_list_entry);
std::unique_ptr<udev_device, UdevDeviceDeleter> dev{udev_device_new_from_syspath(udev, path)};
check_nn(dev.get(), "dev new failed");
upsert_device(first, last, inserter, dev.get());
}
}
bool waybar::modules::Backlight::handleScroll(GdkEventScroll *e) {
// Check if the user has set a custom command for scrolling
if (config_["on-scroll-up"].isString() || config_["on-scroll-down"].isString()) {
return AModule::handleScroll(e);
}
// Fail fast if the proxy could not be initialized
if (!login_proxy_) {
return true;
}
// Check scroll direction
auto dir = AModule::getScrollDir(e);
if (dir == SCROLL_DIR::NONE) {
return true;
}
// Get scroll step
double step = 1;
if (config_["scroll-step"].isDouble()) {
step = config_["scroll-step"].asDouble();
}
// Get the best device
decltype(devices_) devices;
{
std::scoped_lock<std::mutex> lock(udev_thread_mutex_);
devices = devices_;
}
const auto best = best_device(devices.cbegin(), devices.cend(), preferred_device_);
if (best == nullptr) {
return true;
}
// Compute the absolute step
const auto abs_step = static_cast<int>(round(step * best->get_max() / 100.0f));
// Compute the new value
int new_value = best->get_actual();
if (dir == SCROLL_DIR::UP) {
new_value += abs_step;
} else if (dir == SCROLL_DIR::DOWN) {
new_value -= abs_step;
}
// Clamp the value
new_value = std::clamp(new_value, 0, best->get_max());
// Set the new value
auto call_args = Glib::VariantContainerBase(
g_variant_new("(ssu)", "backlight", std::string(best->name()).c_str(), new_value));
login_proxy_->call_sync("SetBrightness", call_args);
return true;
}