feat: add custom module to allow execution of external script

src/factory.cpp

@@ -20,5 +20,7 @@ waybar::IModule &waybar::Factory::makeModule(std::string name)
     return *new waybar::modules::Network(_config[name]);
   if (name == "pulseaudio")
     return *new waybar::modules::Pulseaudio(_config[name]);
+  if (!name.compare(0, 7, "custom/") && name.size() > 7)
+    return *new waybar::modules::Custom(name.substr(7), _config[name]);
   throw std::runtime_error("Unknown module: " + name);
 }

src/modules/cpu.cpp

@@ -1,5 +1,4 @@
 #include "modules/cpu.hpp"
-#include <iostream>
 
 waybar::modules::Cpu::Cpu(Json::Value config)
   : _config(config)

src/modules/custom.cpp

@@ -0,0 +1,50 @@
+#include "modules/custom.hpp"
+#include <iostream>
+
+waybar::modules::Custom::Custom(std::string name, Json::Value config)
+  : _name(name), _config(config)
+{
+  _label.get_style_context()->add_class("custom-" + name);
+  if (!_config["exec"]) {
+    std::cerr << name + " has no exec path." << std::endl;
+    return;
+  }
+  _thread = [this] {
+    update();
+    int interval = _config["interval"] ? _config["inveral"].asInt() : 30;
+    _thread.sleep_for(chrono::seconds(interval));
+  };
+};
+
+auto waybar::modules::Custom::update() -> void
+{
+  std::array<char, 128> buffer;
+  std::string output;
+  std::shared_ptr<FILE> fp(popen(_config["exec"].asCString(), "r"), pclose);
+  if (!fp) {
+    std::cerr << _name + " can't exec " + _config["exec"].asString() << std::endl;
+    return;
+  }
+  while (!feof(fp.get())) {
+    if (fgets(buffer.data(), 128, fp.get()) != nullptr)
+        output += buffer.data();
+  }
+
+  // Remove last newline
+  if (!output.empty() && output[output.length()-1] == '\n') {
+    output.erase(output.length()-1);
+  }
+
+  // Hide label if output is empty
+  if (output.empty())
+    _label.hide();
+  else {
+    auto format = _config["format"] ? _config["format"].asString() : "{}";
+    _label.set_text(fmt::format(format, output));
+    _label.show();
+  }
+}
+
+waybar::modules::Custom::operator Gtk::Widget &() {
+  return _label;
+}

src/modules/network.cpp

@@ -1,7 +1,5 @@
 #include "modules/network.hpp"
 
-#include <iostream>
-
 waybar::modules::Network::Network(Json::Value config)
   : _config(config), _ifid(if_nametoindex(config["interface"].asString().c_str()))
 {

src/modules/pulseaudio.cpp

@@ -1,7 +1,5 @@
 #include "modules/pulseaudio.hpp"
 
-#include <iostream>
-
 waybar::modules::Pulseaudio::Pulseaudio(Json::Value config)
   : _config(config), _mainloop(nullptr), _mainloop_api(nullptr),
     _context(nullptr), _sinkIdx(0), _volume(0), _muted(false)