AppInfo hacks

info.hpp

#pragma once

#include <filesystem>
#include <fstream>
#include <giomm/desktopappinfo.h>
#include <glibmm/keyfile.h>
#include <fmt/core.h>
#include <spdlog/spdlog.h>
#include "util/string.hpp"
#include "util/format.hpp"

/** Utilities for 
 *
 */
namespace waybar::AppInfoProvider {

using AppInfo = Glib::RefPtr<Gio::DesktopAppInfo>;

// snap logic taken from
// https://gitlab.gnome.org/GNOME/mutter/-/blob/main/src/core/window.c#L867-L915

// BAMF_DESKTOP_FILE_HINT logic taken from
// https://invent.kde.org/plasma/plasma-workspace/-/blob/master/libnotificationmanager/utils.cpp#L82-99

// flatpak logic taken from
// https://gitlab.com/carbonOS/gde/gde-panel/-/blob/master/panel/appsys.vala#L59-L76
// https://invent.kde.org/plasma/plasma-workspace/-/blob/master/libnotificationmanager/utils.cpp#L69-80

/**
 * @brief Find desktop file for process running in snap container
 *
 * Tries to read profile name from the security attributes of the process and find a .dekstop file with the matching name
 * @param pid process id
 * @return info from the matched desktop file, null when not found
 */
AppInfo get_app_info_from_snap(uint32_t pid) {
    using namespace std::literals;

    // Example of the content for firefox snap on ubuntu 21.10:
    // snap.firefox.firefox (enforce)
    // We want to lookup:
    // firefox_firefox.desktop

    std::ifstream f{fmt::format("/proc/{}/attr/current", pid)};
    std::string data;
    if(!std::getline(f, data)) {
        return {};
    };

    constexpr auto SNAP_PREFIX = "snap."sv;
    if (!starts_with(data, SNAP_PREFIX)) {
        return {};
    }
    data = data.substr(SNAP_PREFIX.size(), data.find(' ') - SNAP_PREFIX.size());
    std::replace(data.begin(), data.end(), '.', '_');

    return Gio::DesktopAppInfo::create(data + ".desktop");
}


/**
 * @brief Find desktop file for process based on BAMF_DESKTOP_FILE_HINT environment variable
 * @param pid process id
 * @return info from matched desktop file, null when not found
 */
AppInfo get_app_info_from_bamf_env(uint32_t pid) {
    using namespace std::literals;

    constexpr auto ENV_PREFIX = "BAMF_DESKTOP_FILE_HINT="sv;
    std::ifstream f{fmt::format("/proc/{}/environ", pid)};
    std::string data;
    while (std::getline(f, data, '\0')) {
        if (starts_with(data, ENV_PREFIX)) {
            data = data.substr(ENV_PREFIX.size());
            return Gio::DesktopAppInfo::create_from_filename(data);
        }
    }
    return {};
}


/**
 * @brief Find desktop file for process by looking for .flatpak-info file in the process's root
 * @param pid process id
 * @return info from matched desktop file, null when not found
 */
AppInfo get_app_info_from_flatpak(uint32_t pid) {
    namespace fs = std::filesystem;

    fs::path flatpakInfo{fmt::format("/proc/{}/root/.flatpak-info", pid)};
    try {
        if (!fs::is_regular_file(flatpakInfo)) {
            return {};
        }
    }  catch (const std::exception&e) {
        spdlog::error("fs error: {}", e.what());
    }
    Glib::KeyFile keyFile;
    try {
        keyFile.load_from_file(flatpakInfo);
        auto appName = keyFile.get_string("Application", "name");
        return Gio::DesktopAppInfo::create(appName + ".desktop");
    }  catch (const Glib::Error& e) {
        spdlog::error("Keyfile load failed {}", e.what());
        return {};
    }
}

};  // namespace waybar::AppInfoProvider