Hyprland/src/main.cpp

#include "defines.hpp"
#include "debug/log/Logger.hpp"
#include "Compositor.hpp"
#include "config/legacy/ConfigManager.hpp"
#include "init/initHelpers.hpp"
#include "debug/HyprCtl.hpp"
#include "helpers/env/Env.hpp"

#include <csignal>
#include <cstdio>
#include <hyprutils/string/String.hpp>
#include <hyprutils/memory/Casts.hpp>
#include <print>
using namespace Hyprutils::String;
using namespace Hyprutils::Memory;

#include <fcntl.h>
#include <iostream>
#include <iterator>
#include <vector>
#include <stdexcept>
#include <string>
#include <string_view>
#include <span>
#include <filesystem>

static void help() {
    std::println("usage: Hyprland [arg [...]].\n");
    std::println(R"#(Arguments:
    --help              -h       - Show this message again
    --config FILE       -c FILE  - Specify config file to use
    --socket NAME                - Sets the Wayland socket name (for Wayland socket handover)
    --wayland-fd FD              - Sets the Wayland socket fd (for Wayland socket handover)
    --watchdog-fd FD             - Used by start-hyprland
    --safe-mode                  - Starts Hyprland in safe mode
    --systeminfo                 - Prints system infos
    --i-am-really-stupid         - Omits root user privileges check (why would you do that?)
    --verify-config              - Do not run Hyprland, only print if the config has any errors
    --version           -v       - Print this binary's version
    --version-json               - Print this binary's version as json)#");
}

static void reapZombieChildrenAutomatically() {
    struct sigaction act;
    act.sa_handler = SIG_DFL;
    sigemptyset(&act.sa_mask);
    act.sa_flags = SA_NOCLDWAIT;
#ifdef SA_RESTORER
    act.sa_restorer = NULL;
#endif
    sigaction(SIGCHLD, &act, nullptr);
}

int main(int argc, char** argv) {

    if (!getenv("XDG_RUNTIME_DIR"))
        throwError("XDG_RUNTIME_DIR is not set!");

    // export HYPRLAND_CMD
    std::string cmd = argv[0];
    for (int i = 1; i < argc; ++i)
        cmd += std::string(" ") + argv[i];

    setenv("HYPRLAND_CMD", cmd.c_str(), 1);
    setenv("XDG_BACKEND", "wayland", 1);
    setenv("XDG_SESSION_TYPE", "wayland", 1);
    setenv("_JAVA_AWT_WM_NONREPARENTING", "1", 1);
    setenv("MOZ_ENABLE_WAYLAND", "1", 1);

    // parse some args
    std::string configPath;
    std::string socketName;
    int         socketFd   = -1;
    bool        ignoreSudo = false, verifyConfig = false, safeMode = false;
    int         watchdogFd = -1;

    if (argc > 1) {
        std::span<char*> args{argv + 1, sc<std::size_t>(argc - 1)};

        for (auto it = args.begin(); it != args.end(); it++) {
            std::string_view value = *it;

            if (value == "--i-am-really-stupid" && !ignoreSudo) {
                std::println("[ WARNING ] Running Hyprland with superuser privileges might damage your system");

                ignoreSudo = true;
            } else if (value == "--socket") {
                if (std::next(it) == args.end()) {
                    help();

                    return 1;
                }

                socketName = *std::next(it);
                it++;
            } else if (value == "--wayland-fd") {
                if (std::next(it) == args.end()) {
                    help();

                    return 1;
                }

                const auto FD_STR = *std::next(it);
                try {
                    socketFd = std::stoi(FD_STR);

                    // check if socketFd is a valid file descriptor
                    if (fcntl(socketFd, F_GETFD) == -1)
                        throw std::runtime_error("invalid or closed file descriptor");
                } catch (const std::exception& e) {
                    std::println(stderr, "[ ERROR ] (main.cpp:{}) | Invalid Wayland FD '{}': {}!", __LINE__, FD_STR, e.what());
                    help();

                    return 1;
                }

                it++;
            } else if (value == "-c" || value == "--config") {
                if (std::next(it) == args.end()) {
                    help();

                    return 1;
                }
                configPath = *std::next(it);

                try {
                    const auto ABS_PATH = std::filesystem::canonical(configPath);

                    if (!std::filesystem::is_regular_file(ABS_PATH)) {
                        throw std::runtime_error("not a regular file");
                    }
                    configPath = ABS_PATH;
                } catch (const std::exception& e) {
                    std::println(stderr, "[ ERROR ] (main.cpp:{}) | Config file '{}' is invalid: {}!", __LINE__, configPath, e.what());
                    help();

                    return 1;
                }

                Log::logger->log(Log::DEBUG, "User-specified config location: '{}'", configPath);

                it++;

                continue;
            } else if (value == "-h" || value == "--help") {
                help();

                return 0;
            } else if (value == "-v" || value == "--version") {
                std::println("{}", versionRequest(eHyprCtlOutputFormat::FORMAT_NORMAL, ""));
                return 0;
            } else if (value == "--version-json") {
                std::println("{}", versionRequest(eHyprCtlOutputFormat::FORMAT_JSON, ""));
                return 0;
            } else if (value == "--systeminfo") {
                std::println("{}", systemInfoRequest(eHyprCtlOutputFormat::FORMAT_NORMAL, ""));
                return 0;
            } else if (value == "--verify-config") {
                verifyConfig = true;
                continue;
            } else if (value == "--safe-mode") {
                safeMode = true;
                continue;
            } else if (value == "--watchdog-fd") {
                if (std::next(it) == args.end()) {
                    help();
                    return 1;
                }

                const auto WATCHDOG_STR = *std::next(it);
                try {
                    watchdogFd = std::stoi(WATCHDOG_STR);
                    it++;
                } catch (const std::exception& e) {
                    std::println(stderr, "[ ERROR ] (main.cpp:{}) | Invalid watchdog FD '{}': {}!", __LINE__, WATCHDOG_STR, e.what());
                    help();
                    return 1;
                }
            } else {
                std::println(stderr, "[ ERROR ] Unknown option '{}' !", value);
                help();

                return 1;
            }
        }
    }

    if (!ignoreSudo && NInit::isSudo()) {
        std::println(stderr,
                     "[ ERROR ] Hyprland was launched with superuser privileges, but the privileges check is not omitted.\n"
                     "          Hint: Use the --i-am-really-stupid flag to omit that check.");

        return 1;
    } else if (ignoreSudo && NInit::isSudo())
        std::println("Superuser privileges check is omitted. I hope you know what you're doing.");

    if (socketName.empty() ^ (socketFd == -1)) {
        std::println(stderr,
                     "[ ERROR ] Hyprland was launched with only one of --socket and --wayland-fd.\n"
                     "          Hint: Pass both --socket and --wayland-fd to perform Wayland socket handover.");

        return 1;
    }

    if (!verifyConfig) {
        std::println("Welcome to Hyprland!");
        std::println(R"#(
                                                  
                     YY    UJ                     
                    YYY    UUJ                    
                   XXXY    UUUU                   
                  zXXXX    UUUUU                  
                zzzzX        UUUUJ                
               cczzz          UUUUJ               
             vccccz            UUUUUJ             
            vvcccc              UUUUUJ            
           vvvvv                  UUUUJ           
          uuuvv                    UUUUJ          
         uuuuu                      UUUUU         
        nnnuu                        UUUUU        
       nnnnn                          YUUUU       
       xxnn                            YUUU       
       xxxn                            YYUU       
      xxxx                              YYUU      
      rxxx                              YYYY      
      rrrx                              YYYY      
       rrrx                            XXXY       
       rrrr                            XXXX       
        rrrr                          zzXX        
         rrrr                        zzzz         
          rrrrr                    ccczz          
           rrrrrx                vccccc           
             rrrrxxxx        uuvvvvvc             
                rrxxxxxxnnnnuuuuuv                
                    xxxxxnnnnu                    


)#");
    }

    // let's init the compositor.
    // it initializes basic Wayland stuff in the constructor.
    try {
        g_pCompositor                       = makeUnique<CCompositor>(verifyConfig);
        g_pCompositor->m_explicitConfigPath = configPath;
    } catch (const std::exception& e) {
        std::println(stderr, "Hyprland threw in ctor: {}\nCannot continue.", e.what());
        return 1;
    }

    reapZombieChildrenAutomatically();

    bool watchdogOk = watchdogFd > 0;

    if (watchdogFd > 0)
        watchdogOk = g_pCompositor->setWatchdogFd(watchdogFd);
    if (safeMode)
        g_pCompositor->m_safeMode = true;

    if (!watchdogOk && !verifyConfig)
        Log::logger->log(Log::WARN, "WARNING: Hyprland is being launched without start-hyprland. This is highly advised against.");

    g_pCompositor->initServer(socketName, socketFd);

    if (verifyConfig)
        return !Config::mgr()->configVerifPassed();

    if (!Env::envEnabled("HYPRLAND_NO_RT"))
        NInit::gainRealTime();

    Log::logger->log(Log::DEBUG, "Hyprland init finished.");

    // If all's good to go, start.
    g_pCompositor->startCompositor();

    g_pCompositor->cleanup();

    g_pCompositor.reset();

    Log::logger->log(Log::DEBUG, "Hyprland has reached the end.");

    return EXIT_SUCCESS;
}