Added a Hyprland backend and a Window module

include/factory.hpp

@@ -21,6 +21,10 @@
 #include "modules/river/tags.hpp"
 #include "modules/river/window.hpp"
 #endif
+#ifdef HAVE_HYPRLAND
+#include "modules/hyprland/backend.hpp"
+#include "modules/hyprland/window.hpp"
+#endif
 #if defined(__linux__) && !defined(NO_FILESYSTEM)
 #include "modules/battery.hpp"
 #endif

include/modules/hyprland/backend.hpp

@@ -0,0 +1,30 @@
+#pragma once
+#include <string>
+#include <memory>
+#include <mutex>
+#include <deque>
+#include <functional>
+#include <thread>
+
+namespace waybar::modules::hyprland {
+class IPC {
+public:
+  IPC() { startIPC(); }
+
+  void registerForIPC(const std::string&, std::function<void(const std::string&)>);
+
+  std::string getSocket1Reply(const std::string& rq);
+
+private:
+
+ void startIPC();
+ void parseIPC(const std::string&);
+
+ std::mutex callbackMutex;
+ std::deque<std::pair<std::string, std::function<void(const std::string&)>>> callbacks;
+};
+
+inline std::unique_ptr<IPC> gIPC;
+inline bool modulesReady = false;
+};
+

include/modules/hyprland/window.hpp

@@ -0,0 +1,28 @@
+#include <fmt/format.h>
+
+#include <tuple>
+
+#include "ALabel.hpp"
+#include "bar.hpp"
+#include "modules/hyprland/backend.hpp"
+#include "util/json.hpp"
+
+namespace waybar::modules::hyprland {
+
+class Window : public waybar::ALabel {
+public:
+  Window(const std::string&, const waybar::Bar&, const Json::Value&);
+  ~Window() = default;
+
+  auto update() -> void;
+
+private:
+  void onEvent(const std::string&);
+
+  std::mutex mutex_;
+  const Bar& bar_;
+  util::JsonParser parser_;
+  std::string lastView;
+};
+
+}

man/waybar-hyprland-window.5.scd

@@ -0,0 +1,31 @@
+waybar-hyprland-window(5)
+
+# NAME
+
+waybar - hyprland window module
+
+# DESCRIPTION
+
+The *window* module displays the title of the currently focused window in Hyprland.
+
+# CONFIGURATION
+
+Addressed by *hyprland/window*
+
+*format*: ++
+	typeof: string ++
+	default: {} ++
+	The format, how information should be displayed. On {} the current window title is displayed.
+
+
+# EXAMPLES
+
+```
+"hyprland/window": {
+    "format": "{}"
+}
+```
+
+# STYLE
+
+- *#window*

meson.build

@@ -201,6 +201,12 @@ if true
     src_files += 'src/modules/river/window.cpp'
 endif
 
+if true
+    add_project_arguments('-DHAVE_HYPRLAND', language: 'cpp')
+    src_files += 'src/modules/hyprland/backend.cpp'
+    src_files += 'src/modules/hyprland/window.cpp'
+endif
+
 if libnl.found() and libnlgen.found()
     add_project_arguments('-DHAVE_LIBNL', language: 'cpp')
     src_files += 'src/modules/network.cpp'

src/factory.cpp

@@ -56,6 +56,11 @@ waybar::AModule* waybar::Factory::makeModule(const std::string& name) const {
     if (ref == "river/window") {
       return new waybar::modules::river::Window(id, bar_, config_[name]);
     }
+#endif
+#ifdef HAVE_HYPRLAND
+    if (ref == "hyprland/window") {
+      return new waybar::modules::hyprland::Window(id, bar_, config_[name]);
+    }
 #endif
     if (ref == "idle_inhibitor") {
       return new waybar::modules::IdleInhibitor(id, bar_, config_[name]);

src/modules/hyprland/backend.cpp

@@ -0,0 +1,171 @@
+#include "modules/hyprland/backend.hpp"
+
+#include <ctype.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <spdlog/spdlog.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include <fstream>
+#include <iostream>
+#include <string>
+
+namespace waybar::modules::hyprland {
+
+void IPC::startIPC() {
+  // will start IPC and relay events to parseIPC
+
+  std::thread([&]() {
+    // check for hyprland
+    const char* HIS = getenv("HYPRLAND_INSTANCE_SIGNATURE");
+
+    if (!HIS) {
+      spdlog::warn("Hyprland is not running, Hyprland IPC will not be available.");
+      return;
+    }
+
+    if (!modulesReady) return;
+
+    spdlog::info("Hyprland IPC starting");
+
+    struct sockaddr_un addr;
+    int socketfd = socket(AF_UNIX, SOCK_STREAM, 0);
+
+    if (socketfd == -1) {
+      spdlog::error("Hyprland IPC: socketfd failed");
+      return;
+    }
+
+    addr.sun_family = AF_UNIX;
+
+    // socket path
+    std::string socketPath = "/tmp/hypr/" + std::string(HIS) + "/.socket2.sock";
+
+    strncpy(addr.sun_path, socketPath.c_str(), sizeof(addr.sun_path) - 1);
+
+    addr.sun_path[sizeof(addr.sun_path) - 1] = 0;
+
+    int l = sizeof(struct sockaddr_un);
+
+    if (connect(socketfd, (struct sockaddr*)&addr, l) == -1) {
+      spdlog::error("Hyprland IPC: Unable to connect?");
+      return;
+    }
+
+    auto file = fdopen(socketfd, "r");
+
+    while (1) {
+      // read
+
+      char buffer[1024];  // Hyprland socket2 events are max 1024 bytes
+      auto recievedCharPtr = fgets(buffer, 1024, file);
+
+      if (!recievedCharPtr) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(1));
+        continue;
+      }
+
+      callbackMutex.lock();
+
+      std::string messageRecieved(buffer);
+
+      messageRecieved = messageRecieved.substr(0, messageRecieved.find_first_of('\n'));
+
+      spdlog::debug("hyprland IPC received {}", messageRecieved);
+
+      parseIPC(messageRecieved);
+
+      callbackMutex.unlock();
+
+      std::this_thread::sleep_for(std::chrono::milliseconds(1));
+    }
+  }).detach();
+}
+
+void IPC::parseIPC(const std::string& ev) {
+  // todo
+  std::string request = ev.substr(0, ev.find_first_of('>'));
+
+  for (auto& [eventname, handler] : callbacks) {
+    if (eventname == request) {
+      handler(ev);
+    }
+  }
+}
+
+void IPC::registerForIPC(const std::string& ev, std::function<void(const std::string&)> fn) {
+  callbackMutex.lock();
+
+  callbacks.emplace_back(std::make_pair(ev, fn));
+
+  callbackMutex.unlock();
+}
+
+std::string IPC::getSocket1Reply(const std::string& rq) {
+  // basically hyprctl
+
+  const auto SERVERSOCKET = socket(AF_UNIX, SOCK_STREAM, 0);
+
+  if (SERVERSOCKET < 0) {
+    spdlog::error("Hyprland IPC: Couldn't open a socket (1)");
+    return "";
+  }
+
+  const auto SERVER = gethostbyname("localhost");
+
+  if (!SERVER) {
+    spdlog::error("Hyprland IPC: Couldn't get host (2)");
+    return "";
+  }
+
+  // get the instance signature
+  auto instanceSig = getenv("HYPRLAND_INSTANCE_SIGNATURE");
+
+  if (!instanceSig) {
+    spdlog::error("Hyprland IPC: HYPRLAND_INSTANCE_SIGNATURE was not set! (Is Hyprland running?)");
+    return "";
+  }
+
+  std::string instanceSigStr = std::string(instanceSig);
+
+  sockaddr_un serverAddress = {0};
+  serverAddress.sun_family = AF_UNIX;
+
+  std::string socketPath = "/tmp/hypr/" + instanceSigStr + "/.socket.sock";
+
+  strcpy(serverAddress.sun_path, socketPath.c_str());
+
+  if (connect(SERVERSOCKET, (sockaddr*)&serverAddress, SUN_LEN(&serverAddress)) < 0) {
+    spdlog::error("Hyprland IPC: Couldn't connect to " + socketPath + ". (3)");
+    return "";
+  }
+
+  auto sizeWritten = write(SERVERSOCKET, rq.c_str(), rq.length());
+
+  if (sizeWritten < 0) {
+    spdlog::error("Hyprland IPC: Couldn't write (4)");
+    return "";
+  }
+
+  char buffer[8192] = {0};
+
+  sizeWritten = read(SERVERSOCKET, buffer, 8192);
+
+  if (sizeWritten < 0) {
+    spdlog::error("Hyprland IPC: Couldn't read (5)");
+    return "";
+  }
+
+  close(SERVERSOCKET);
+
+  return std::string(buffer);
+}
+
+}  // namespace waybar::modules::hyprland

src/modules/hyprland/window.cpp

@@ -0,0 +1,63 @@
+#include "modules/hyprland/window.hpp"
+
+#include <spdlog/spdlog.h>
+
+#include "modules/hyprland/backend.hpp"
+
+namespace waybar::modules::hyprland {
+
+Window::Window(const std::string& id, const Bar& bar, const Json::Value& config)
+    : ALabel(config, "window", id, "{}", 0, true), bar_(bar) {
+  modulesReady = true;
+
+  if (!gIPC.get()) {
+    gIPC = std::make_unique<IPC>();
+  }
+
+  label_.hide();
+  ALabel::update();
+
+  // register for hyprland ipc
+  gIPC->registerForIPC("activewindow", [&](const std::string& ev) { this->onEvent(ev); });
+}
+
+auto Window::update() -> void {
+  // fix ampersands
+  std::lock_guard<std::mutex> lg(mutex_);
+
+  if (!format_.empty()) {
+    label_.show();
+    label_.set_markup(fmt::format(format_, lastView));
+  } else {
+    label_.hide();
+  }
+
+  ALabel::update();
+}
+
+void Window::onEvent(const std::string& ev) {
+  std::lock_guard<std::mutex> lg(mutex_);
+  auto windowName = ev.substr(ev.find_first_of(',') + 1).substr(0, 256);
+
+  auto replaceAll = [](std::string str, const std::string& from,
+                       const std::string& to) -> std::string {
+    size_t start_pos = 0;
+    while ((start_pos = str.find(from, start_pos)) != std::string::npos) {
+      str.replace(start_pos, from.length(), to);
+      start_pos += to.length();
+    }
+    return str;
+  };
+
+  windowName = replaceAll(windowName, "&", "&amp;");
+
+  if (windowName == lastView) return;
+
+  lastView = windowName;
+
+  spdlog::debug("hyprland window onevent with {}", windowName);
+
+  dp.emit();
+}
+
+}  // namespace waybar::modules::hyprland