serenity/Applications/ProcessManager/ProcessModel.cpp

#include "ProcessModel.h"
#include "GraphWidget.h"
#include <AK/JsonArray.h>
#include <AK/JsonObject.h>
#include <AK/JsonValue.h>
#include <LibCore/CFile.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>

ProcessModel::ProcessModel(GraphWidget& graph)
    : m_graph(graph)
    , m_proc_all("/proc/all")
{
    if (!m_proc_all.open(CIODevice::ReadOnly)) {
        fprintf(stderr, "ProcessManager: Failed to open /proc/all: %s\n", m_proc_all.error_string());
        exit(1);
    }

    setpwent();
    while (auto* passwd = getpwent())
        m_usernames.set(passwd->pw_uid, passwd->pw_name);
    endpwent();

    m_generic_process_icon = GraphicsBitmap::load_from_file("/res/icons/gear16.png");
    m_high_priority_icon = GraphicsBitmap::load_from_file("/res/icons/highpriority16.png");
    m_low_priority_icon = GraphicsBitmap::load_from_file("/res/icons/lowpriority16.png");
    m_normal_priority_icon = GraphicsBitmap::load_from_file("/res/icons/normalpriority16.png");
}

ProcessModel::~ProcessModel()
{
}

int ProcessModel::row_count(const GModelIndex&) const
{
    return m_pids.size();
}

int ProcessModel::column_count(const GModelIndex&) const
{
    return Column::__Count;
}

String ProcessModel::column_name(int column) const
{
    switch (column) {
    case Column::Icon:
        return "";
    case Column::PID:
        return "PID";
    case Column::State:
        return "State";
    case Column::User:
        return "User";
    case Column::Priority:
        return "Pr";
    case Column::Virtual:
        return "Virtual";
    case Column::Physical:
        return "Physical";
    case Column::CPU:
        return "CPU";
    case Column::Name:
        return "Name";
    case Column::Syscalls:
        return "Syscalls";
    default:
        ASSERT_NOT_REACHED();
    }
}

GModel::ColumnMetadata ProcessModel::column_metadata(int column) const
{
    switch (column) {
    case Column::Icon:
        return { 16, TextAlignment::CenterLeft };
    case Column::PID:
        return { 32, TextAlignment::CenterRight };
    case Column::State:
        return { 75, TextAlignment::CenterLeft };
    case Column::Priority:
        return { 16, TextAlignment::CenterLeft };
    case Column::User:
        return { 50, TextAlignment::CenterLeft };
    case Column::Virtual:
        return { 65, TextAlignment::CenterRight };
    case Column::Physical:
        return { 65, TextAlignment::CenterRight };
    case Column::CPU:
        return { 32, TextAlignment::CenterRight };
    case Column::Name:
        return { 140, TextAlignment::CenterLeft };
    case Column::Syscalls:
        return { 60, TextAlignment::CenterRight };
    default:
        ASSERT_NOT_REACHED();
    }
}

static String pretty_byte_size(size_t size)
{
    return String::format("%uK", size / 1024);
}

GVariant ProcessModel::data(const GModelIndex& index, Role role) const
{
    ASSERT(is_valid(index));

    auto it = m_processes.find(m_pids[index.row()]);
    auto& process = *(*it).value;

    if (role == Role::Sort) {
        switch (index.column()) {
        case Column::Icon:
            return 0;
        case Column::PID:
            return process.current_state.pid;
        case Column::State:
            return process.current_state.state;
        case Column::User:
            return process.current_state.user;
        case Column::Priority:
            if (process.current_state.priority == "Idle")
                return 0;
            if (process.current_state.priority == "Low")
                return 1;
            if (process.current_state.priority == "Normal")
                return 2;
            if (process.current_state.priority == "High")
                return 3;
            ASSERT_NOT_REACHED();
            return 3;
        case Column::Virtual:
            return (int)process.current_state.virtual_size;
        case Column::Physical:
            return (int)process.current_state.physical_size;
        case Column::CPU:
            return process.current_state.cpu_percent;
        case Column::Name:
            return process.current_state.name;
        // FIXME: GVariant with unsigned?
        case Column::Syscalls:
            return (int)process.current_state.syscalls;
        }
        ASSERT_NOT_REACHED();
        return {};
    }

    if (role == Role::Display) {
        switch (index.column()) {
        case Column::Icon:
            return *m_generic_process_icon;
        case Column::PID:
            return process.current_state.pid;
        case Column::State:
            return process.current_state.state;
        case Column::User:
            return process.current_state.user;
        case Column::Priority:
            if (process.current_state.priority == "Idle")
                return String::empty();
            if (process.current_state.priority == "High")
                return *m_high_priority_icon;
            if (process.current_state.priority == "Low")
                return *m_low_priority_icon;
            if (process.current_state.priority == "Normal")
                return *m_normal_priority_icon;
            return process.current_state.priority;
        case Column::Virtual:
            return pretty_byte_size(process.current_state.virtual_size);
        case Column::Physical:
            return pretty_byte_size(process.current_state.physical_size);
        case Column::CPU:
            return process.current_state.cpu_percent;
        case Column::Name:
            return process.current_state.name;
        // FIXME: It's weird that GVariant doesn't support unsigned ints. Should it?
        case Column::Syscalls:
            return (int)process.current_state.syscalls;
        }
    }

    return {};
}

void ProcessModel::update()
{
    m_proc_all.seek(0);

    unsigned last_sum_nsched = 0;
    for (auto& it : m_processes)
        last_sum_nsched += it.value->current_state.nsched;

    HashTable<pid_t> live_pids;
    unsigned sum_nsched = 0;
    auto file_contents = m_proc_all.read_all();
    auto json = JsonValue::from_string({ file_contents.data(), file_contents.size() });
    json.as_array().for_each([&](auto& value) {
        const JsonObject& process_object = value.as_object();
        pid_t pid = process_object.get("pid").to_u32();
        unsigned nsched = process_object.get("times_scheduled").to_u32();
        ProcessState state;
        state.pid = pid;
        state.nsched = nsched;
        unsigned uid = process_object.get("uid").to_u32();
        {
            auto it = m_usernames.find((uid_t)uid);
            if (it != m_usernames.end())
                state.user = (*it).value;
            else
                state.user = String::number(uid);
        }
        state.priority = process_object.get("priority").to_string();
        state.syscalls = process_object.get("syscall_count").to_u32();
        state.state = process_object.get("state").to_string();
        state.name = process_object.get("name").to_string();
        state.virtual_size = process_object.get("amount_virtual").to_u32();
        state.physical_size = process_object.get("amount_resident").to_u32();
        sum_nsched += nsched;
        {
            auto it = m_processes.find(pid);
            if (it == m_processes.end())
                m_processes.set(pid, make<Process>());
        }
        auto it = m_processes.find(pid);
        ASSERT(it != m_processes.end());
        (*it).value->previous_state = (*it).value->current_state;
        (*it).value->current_state = state;

        live_pids.set(pid);
    });

    m_pids.clear();
    float total_cpu_percent = 0;
    Vector<pid_t, 16> pids_to_remove;
    for (auto& it : m_processes) {
        if (!live_pids.contains(it.key)) {
            pids_to_remove.append(it.key);
            continue;
        }
        auto& process = *it.value;
        u32 nsched_diff = process.current_state.nsched - process.previous_state.nsched;
        process.current_state.cpu_percent = ((float)nsched_diff * 100) / (float)(sum_nsched - last_sum_nsched);
        if (it.key != 0) {
            total_cpu_percent += process.current_state.cpu_percent;
            m_pids.append(it.key);
        }
    }
    for (auto pid : pids_to_remove)
        m_processes.remove(pid);

    m_graph.add_value(total_cpu_percent);

    did_update();
}