// 
// Sysinfo
// 
// Copyright (c) 2015 Guillaume Gomez
//

use sys::ffi;
use sys::component::Component;
use sys::network::{self, NetworkData};
use sys::processor::*;
use sys::process::*;
use sys::disk::{self, Disk, DiskType};
use ::{ComponentExt, DiskExt, ProcessExt, ProcessorExt, SystemExt};
use std::collections::HashMap;
use std::ffi::{OsStr, OsString};
use std::os::unix::ffi::OsStringExt;
use libc::{self, c_void, c_int, size_t, c_char, sysconf, _SC_PAGESIZE};
use std::sync::Arc;
use sys::processor;
use std::{fs, mem, ptr};
use utils;
use Pid;

use rayon::prelude::*;

/// Structs containing system's information.
pub struct System {
    process_list: HashMap<Pid, Process>,
    mem_total: u64,
    mem_free: u64,
    swap_total: u64,
    swap_free: u64,
    processors: Vec<Processor>,
    page_size_kb: u64,
    temperatures: Vec<Component>,
    connection: Option<ffi::io_connect_t>,
    disks: Vec<Disk>,
    network: NetworkData,
    uptime: u64,
}

impl Drop for System {
    fn drop(&mut self) {
        if let Some(conn) = self.connection {
            unsafe { ffi::IOServiceClose(conn); }
        }
    }
}

// code from https://github.com/Chris911/iStats
fn get_io_service_connection() -> Option<ffi::io_connect_t> {
    let mut master_port: ffi::mach_port_t = 0;
    let mut iterator: ffi::io_iterator_t = 0;

    unsafe {
        ffi::IOMasterPort(ffi::MACH_PORT_NULL, &mut master_port);

        let matching_dictionary = ffi::IOServiceMatching(b"AppleSMC\0".as_ptr() as *const i8);
        let result = ffi::IOServiceGetMatchingServices(master_port, matching_dictionary,
                                                       &mut iterator);
        if result != ffi::KIO_RETURN_SUCCESS {
            //println!("Error: IOServiceGetMatchingServices() = {}", result);
            return None;
        }

        let device = ffi::IOIteratorNext(iterator);
        ffi::IOObjectRelease(iterator);
        if device == 0 {
            //println!("Error: no SMC found");
            return None;
        }

        let mut conn = 0;
        let result = ffi::IOServiceOpen(device, ffi::mach_task_self(), 0, &mut conn);
        ffi::IOObjectRelease(device);
        if result != ffi::KIO_RETURN_SUCCESS {
            //println!("Error: IOServiceOpen() = {}", result);
            return None;
        }

        Some(conn)
    }
}

unsafe fn strtoul(s: *mut c_char, size: c_int, base: c_int) -> u32 {
    let mut total = 0u32;

    for i in 0..size {
        total += if base == 16 {
            (*s.offset(i as isize) as u32) << (((size - 1 - i) as u32) << 3)
        } else {
            (*s.offset(i as isize) as u32) << ((size - 1 - i) << 3) as u32
        };
    }
    total
}

unsafe fn ultostr(s: *mut c_char, val: u32) {
    *s = 0;
    libc::sprintf(s, b"%c%c%c%c\0".as_ptr() as *const i8, val >> 24, val >> 16, val >> 8, val);
}

unsafe fn perform_call(conn: ffi::io_connect_t, index: c_int, input_structure: *mut ffi::KeyData_t,
                       output_structure: *mut ffi::KeyData_t) -> i32 {
    let mut structure_output_size = ::std::mem::size_of::<ffi::KeyData_t>();

    ffi::IOConnectCallStructMethod(conn, index as u32,
                                   input_structure, ::std::mem::size_of::<ffi::KeyData_t>(),
                                   output_structure, &mut structure_output_size)
}

unsafe fn read_key(con: ffi::io_connect_t, key: *mut c_char) -> Result<ffi::Val_t, i32> {
    let mut input_structure: ffi::KeyData_t = ::std::mem::zeroed::<ffi::KeyData_t>();
    let mut output_structure: ffi::KeyData_t = ::std::mem::zeroed::<ffi::KeyData_t>();
    let mut val: ffi::Val_t = ::std::mem::zeroed::<ffi::Val_t>();

    input_structure.key = strtoul(key, 4, 16);
    input_structure.data8 = ffi::SMC_CMD_READ_KEYINFO;

    let result = perform_call(con, ffi::KERNEL_INDEX_SMC, &mut input_structure,
                              &mut output_structure);
    if result != ffi::KIO_RETURN_SUCCESS {
        return Err(result);
    }

    val.data_size = output_structure.key_info.data_size;
    ultostr(val.data_type.as_mut_ptr(), output_structure.key_info.data_type);
    input_structure.key_info.data_size = val.data_size;
    input_structure.data8 = ffi::SMC_CMD_READ_BYTES;

    let result = perform_call(con, ffi::KERNEL_INDEX_SMC, &mut input_structure,
                              &mut output_structure);
    if result != ffi::KIO_RETURN_SUCCESS {
        Err(result)
    } else {
        libc::memcpy(val.bytes.as_mut_ptr() as *mut c_void,
                     output_structure.bytes.as_mut_ptr() as *mut c_void,
                     ::std::mem::size_of::<[u8; 32]>());
        Ok(val)
    }
}

unsafe fn get_temperature(con: ffi::io_connect_t, key: *mut c_char) -> f32 {
    if let Ok(val) = read_key(con, key) {
        if val.data_size > 0 &&
           libc::strcmp(val.data_type.as_ptr(), b"sp78\0".as_ptr() as *const i8) == 0 {
            // convert fp78 value to temperature
            let x = (i32::from(val.bytes[0]) << 6) + (i32::from(val.bytes[1]) >> 2);
            return x as f32 / 64f32;
        }
    }
    0f32
}

unsafe fn get_unchecked_str(cp: *mut u8, start: *mut u8) -> String {
    let len = cp as usize - start as usize;
    let part = Vec::from_raw_parts(start, len, len);
    let tmp = String::from_utf8_unchecked(part.clone());
    ::std::mem::forget(part);
    tmp
}

macro_rules! unwrapper {
    ($b:expr, $ret:expr) => {{
        match $b {
            Ok(x) => x,
            _ => return $ret, 
        }
    }}
}

unsafe fn check_value(dict: ffi::CFMutableDictionaryRef, key: &[u8]) -> bool {
    let key = ffi::CFStringCreateWithCStringNoCopy(ptr::null_mut(), key.as_ptr() as *const c_char,
                                                   ffi::kCFStringEncodingMacRoman,
                                                   ffi::kCFAllocatorNull as *mut c_void);
    let ret = ffi::CFDictionaryContainsKey(dict as ffi::CFDictionaryRef,
                                           key as *const c_void) != 0 &&
    *(ffi::CFDictionaryGetValue(dict as ffi::CFDictionaryRef,
                                key as *const c_void) as *const ffi::Boolean) != 0;
    ffi::CFRelease(key as *const c_void);
    ret
}

fn make_name(v: &[u8]) -> OsString {
    for (pos, x) in v.iter().enumerate() {
        if *x == 0 {
            return OsStringExt::from_vec(v[0..pos].to_vec())
        }
    }
    OsStringExt::from_vec(v.to_vec())
}

fn get_disk_types() -> HashMap<OsString, DiskType> {
    let mut master_port: ffi::mach_port_t = 0;
    let mut media_iterator: ffi::io_iterator_t = 0;
    let mut ret = HashMap::new();

    unsafe {
        ffi::IOMasterPort(ffi::MACH_PORT_NULL, &mut master_port);

        let matching_dictionary = ffi::IOServiceMatching(b"IOMedia\0".as_ptr() as *const i8);
        let result = ffi::IOServiceGetMatchingServices(master_port, matching_dictionary,
                                                       &mut media_iterator);
        if result != ffi::KERN_SUCCESS as i32 {
            //println!("Error: IOServiceGetMatchingServices() = {}", result);
            return ret;
        }

        loop {
            let next_media = ffi::IOIteratorNext(media_iterator);
            if next_media == 0 {
                break;
            }
            let mut props = mem::uninitialized();
            let result = ffi::IORegistryEntryCreateCFProperties(next_media, &mut props,
                                                                ffi::kCFAllocatorDefault, 0);
            if result == ffi::KERN_SUCCESS as i32 && check_value(props, b"Whole\0") {
                let mut name: ffi::io_name_t = mem::zeroed();
                if ffi::IORegistryEntryGetName(next_media,
                                               name.as_mut_ptr() as *mut c_char)
                    == ffi::KERN_SUCCESS as i32 {
                    ret.insert(make_name(&name),
                               if check_value(props, b"RAID\0") {
                                   DiskType::Unknown(-1)
                               } else {
                                   DiskType::SSD
                               });
                }
                ffi::CFRelease(props as *mut c_void);
            }
            ffi::IOObjectRelease(next_media);
        }
        ffi::IOObjectRelease(media_iterator);
    }
    ret
}

fn get_disks() -> Vec<Disk> {
    let disk_types = get_disk_types();

    unwrapper!(fs::read_dir("/Volumes"), Vec::new())
        .flat_map(|x| {
            if let Ok(ref entry) = x {
                let mount_point = utils::realpath(&entry.path());
                if mount_point.as_os_str().is_empty() {
                    None
                } else {
                    let name = entry.path()
                                    .file_name()
                                    .unwrap_or_else(|| OsStr::new(""))
                                    .to_owned();
                    let type_ = disk_types.get(&name).cloned().unwrap_or(DiskType::Unknown(-2));
                    Some(disk::new(name, &mount_point, type_))
                }
            } else {
                None
            }
        })
        .collect()
}

fn get_uptime() -> u64 {
    let mut boottime: libc::timeval = unsafe { ::std::mem::zeroed() };
    let mut len = ::std::mem::size_of::<libc::timeval>();
    let mut mib: [c_int; 2] = [libc::CTL_KERN, libc::KERN_BOOTTIME];
    unsafe {
        if libc::sysctl(mib.as_mut_ptr(),

                           2,
                           &mut boottime as *mut libc::timeval as *mut _,
                           &mut len,
                           ::std::ptr::null_mut(), 0) < 0 {
            return 0;
        }
    }
    let bsec = boottime.tv_sec;
    let csec = unsafe { libc::time(::std::ptr::null_mut()) };

    unsafe { libc::difftime(csec, bsec) as u64 }
}

struct Wrap<'a>(&'a mut HashMap<Pid, Process>);

unsafe impl<'a> Send for Wrap<'a> {}
unsafe impl<'a> Sync for Wrap<'a> {}

fn update_process(wrap: &mut Wrap, pid: Pid,
                  taskallinfo_size: i32, taskinfo_size: i32, threadinfo_size: i32,
                  mib: &mut [c_int], mut size: size_t) -> Result<Option<Process>, ()> {
    let mut proc_args = Vec::with_capacity(size as usize);
    unsafe {
        let mut thread_info = ::std::mem::zeroed::<libc::proc_threadinfo>();
        let (user_time, system_time, thread_status) = if ffi::proc_pidinfo(pid,
                             libc::PROC_PIDTHREADINFO,
                             0,
                             &mut thread_info as *mut libc::proc_threadinfo as *mut c_void,
                             threadinfo_size) != 0 {
            (thread_info.pth_user_time,
             thread_info.pth_system_time,
             Some(ThreadStatus::from(thread_info.pth_run_state)))
        } else {
            (0, 0, None)
        };
        if let Some(ref mut p) = wrap.0.get_mut(&pid) {
            p.status = thread_status;
            let mut task_info = ::std::mem::zeroed::<libc::proc_taskinfo>();
            if ffi::proc_pidinfo(pid,
                                 libc::PROC_PIDTASKINFO,
                                 0,
                                 &mut task_info as *mut libc::proc_taskinfo as *mut c_void,
                                 taskinfo_size) != taskinfo_size {
                return Err(());
            }
            let task_time = user_time + system_time
                + task_info.pti_total_user + task_info.pti_total_system;
            let time = ffi::mach_absolute_time();
            compute_cpu_usage(p, time, task_time);

            p.memory = task_info.pti_resident_size >> 10; // divide by 1024
            return Ok(None);
        }

        let mut task_info = ::std::mem::zeroed::<libc::proc_taskallinfo>();
        if ffi::proc_pidinfo(pid,
                             libc::PROC_PIDTASKALLINFO,
                             0,
                             &mut task_info as *mut libc::proc_taskallinfo as *mut c_void,
                             taskallinfo_size as i32) != taskallinfo_size as i32 {
            return Err(());
        }

        let parent = match task_info.pbsd.pbi_ppid as Pid {
            0 => None,
            p => Some(p)
        };

        let mut p = Process::new(pid,
                                 parent,
                                 task_info.pbsd.pbi_start_tvsec);
        p.memory = task_info.ptinfo.pti_resident_size >> 10; // divide by 1024

        p.uid = task_info.pbsd.pbi_uid;
        p.gid = task_info.pbsd.pbi_gid;
        p.process_status = ProcessStatus::from(task_info.pbsd.pbi_status);

        let ptr: *mut u8 = proc_args.as_mut_slice().as_mut_ptr();
        mib[0] = libc::CTL_KERN;
        mib[1] = libc::KERN_PROCARGS2;
        mib[2] = pid as c_int;
        /*
        * /---------------\ 0x00000000
        * | ::::::::::::: |
        * |---------------| <-- Beginning of data returned by sysctl() is here.
        * | argc          |
        * |---------------|
        * | exec_path     |
        * |---------------|
        * | 0             |
        * |---------------|
        * | arg[0]        |
        * |---------------|
        * | 0             |
        * |---------------|
        * | arg[n]        |
        * |---------------|
        * | 0             |
        * |---------------|
        * | env[0]        |
        * |---------------|
        * | 0             |
        * |---------------|
        * | env[n]        |
        * |---------------|
        * | ::::::::::::: |
        * |---------------| <-- Top of stack.
        * :               :
        * :               :
        * \---------------/ 0xffffffff
        */
        if libc::sysctl(mib.as_mut_ptr(), 3, ptr as *mut c_void,
                        &mut size, ::std::ptr::null_mut(), 0) != -1 {
            let mut n_args: c_int = 0;
            libc::memcpy((&mut n_args) as *mut c_int as *mut c_void, ptr as *const c_void,
                         ::std::mem::size_of::<c_int>());
            let mut cp = ptr.offset(::std::mem::size_of::<c_int>() as isize);
            let mut start = cp;
            if cp < ptr.offset(size as isize) {
                while cp < ptr.offset(size as isize) && *cp != 0 {
                    cp = cp.offset(1);
                }
                p.exe = get_unchecked_str(cp, start);
                if let Some(l) = p.exe.split('/').last() {
                    p.name = l.to_owned();
                }
                while cp < ptr.offset(size as isize) && *cp == 0 {
                    cp = cp.offset(1);
                }
                start = cp;
                let mut c = 0;
                let mut cmd = Vec::new();
                while c < n_args && cp < ptr.offset(size as isize) {
                    if *cp == 0 {
                        c += 1;
                        cmd.push(get_unchecked_str(cp, start));
                        start = cp.offset(1);
                    }
                    cp = cp.offset(1);
                }
                p.cmd = cmd;
                start = cp;
                while cp < ptr.offset(size as isize) {
                    if *cp == 0 {
                        if cp == start {
                            break;
                        }
                        p.environ.push(get_unchecked_str(cp, start));
                        start = cp.offset(1);
                    }
                    cp = cp.offset(1);
                }
            }
        } else {
            // we don't have enough priviledges to get access to these info
            return Err(());
        }
        Ok(Some(p))
    }
}

impl System {
    fn clear_procs(&mut self) {
        let mut to_delete = Vec::new();

        for (pid, mut proc_) in &mut self.process_list {
            if !has_been_updated(&mut proc_) {
                to_delete.push(*pid);
            }
        }
        for pid in to_delete {
            self.process_list.remove(&pid);
        }
    }
}

impl SystemExt for System {
    fn new() -> System {
        let mut s = System {
            process_list: HashMap::new(),
            mem_total: 0,
            mem_free: 0,
            swap_total: 0,
            swap_free: 0,
            processors: Vec::new(),
            page_size_kb: unsafe { sysconf(_SC_PAGESIZE) as u64 >> 10 }, // divide by 1024
            temperatures: Vec::new(),
            connection: get_io_service_connection(),
            disks: get_disks(),
            network: network::new(),
            uptime: get_uptime(),
        };
        s.refresh_all();
        s
    }

    fn refresh_system(&mut self) {
        self.uptime = get_uptime();
        unsafe fn get_sys_value(high: u32, low: u32, mut len: usize, value: *mut c_void,
                                mib: &mut [i32; 2]) -> bool {
            mib[0] = high as i32;
            mib[1] = low as i32;
            libc::sysctl(mib.as_mut_ptr(), 2, value, &mut len as *mut usize,
                         ::std::ptr::null_mut(), 0) == 0
        }

        let mut mib = [0, 0];
        unsafe {
            // get system values
            // get swap info
            let mut xs: ffi::xsw_usage = ::std::mem::zeroed::<ffi::xsw_usage>();
            if get_sys_value(ffi::CTL_VM, ffi::VM_SWAPUSAGE,
                             ::std::mem::size_of::<ffi::xsw_usage>(),
                             &mut xs as *mut ffi::xsw_usage as *mut c_void, &mut mib) {
                self.swap_total = xs.xsu_total >> 10; // divide by 1024
                self.swap_free = xs.xsu_avail >> 10; // divide by 1024
            }
            // get ram info
            if self.mem_total < 1 {
                get_sys_value(ffi::CTL_HW, ffi::HW_MEMSIZE, ::std::mem::size_of::<u64>(),
                              &mut self.mem_total as *mut u64 as *mut c_void, &mut mib);
                self.mem_total >>= 10; // divide by 1024
            }
            let count: u32 = ffi::HOST_VM_INFO64_COUNT;
            let mut stat = ::std::mem::zeroed::<ffi::vm_statistics64>();
            if ffi::host_statistics64(ffi::mach_host_self(), ffi::HOST_VM_INFO64,
                                      &mut stat as *mut ffi::vm_statistics64 as *mut c_void,
                                      &count as *const u32) == ffi::KERN_SUCCESS {
                self.mem_free = u64::from(stat.free_count + stat.inactive_count
                                          + stat.speculative_count) * self.page_size_kb;
            }

            if let Some(con) = self.connection {
                if self.temperatures.len() < 1 {
                    // getting CPU critical temperature
                    let mut v = vec!('T' as i8, 'C' as i8, '0' as i8, 'D' as i8, 0);
                    let tmp = get_temperature(con, v.as_mut_ptr());
                    let critical_temp = if tmp > 0f32 {
                        Some(tmp)
                    } else {
                        None
                    };
                    // getting CPU temperature
                    // "TC0P"
                    v[3] = 'P' as i8;
                    let temp = get_temperature(con, v.as_mut_ptr() as *mut i8);
                    if temp > 0f32 {
                        self.temperatures.push(Component::new("CPU".to_owned(),
                                                              None, critical_temp));
                    }
                    // getting GPU temperature
                    // "TG0P"
                    v[1] = 'G' as i8;
                    let temp = get_temperature(con, v.as_mut_ptr() as *mut i8);
                    if temp > 0f32 {
                        self.temperatures.push(Component::new("GPU".to_owned(),
                                                              None, critical_temp));
                    }
                    // getting battery temperature
                    // "TB0T"
                    v[1] = 'B' as i8;
                    v[3] = 'T' as i8;
                    let temp = get_temperature(con, v.as_mut_ptr() as *mut i8);
                    if temp > 0f32 {
                        self.temperatures.push(Component::new("Battery".to_owned(),
                                                              None, critical_temp));
                    }
                } else {
                    let mut v = vec!('T' as i8, 'C' as i8, '0' as i8, 'P' as i8, 0);
                    for comp in &mut self.temperatures {
                        match &*comp.get_label() {
                            "CPU" => {
                                v[1] = 'C' as i8;
                                v[3] = 'P' as i8;
                            }
                            "GPU" => {
                                v[1] = 'G' as i8;
                                v[3] = 'P' as i8;
                            }
                            _ => {
                                v[1] = 'B' as i8;
                                v[3] = 'T' as i8;
                            }
                        };
                        let temp = get_temperature(con, v.as_mut_ptr() as *mut i8);
                        ::sys::component::update_component(comp, temp);
                    }
                }
            }

            // get processor values
            let mut num_cpu_u = 0u32;
            let mut cpu_info: *mut i32 = ::std::ptr::null_mut();
            let mut num_cpu_info = 0u32;

            if self.processors.is_empty() {
                let mut num_cpu = 0;

                if !get_sys_value(ffi::CTL_HW, ffi::HW_NCPU, ::std::mem::size_of::<u32>(),
                                  &mut num_cpu as *mut usize as *mut c_void, &mut mib) {
                    num_cpu = 1;
                }

                self.processors.push(
                    processor::create_proc("0".to_owned(),
                                           Arc::new(ProcessorData::new(::std::ptr::null_mut(), 0))));
                if ffi::host_processor_info(ffi::mach_host_self(), ffi::PROCESSOR_CPU_LOAD_INFO,
                                       &mut num_cpu_u as *mut u32,
                                       &mut cpu_info as *mut *mut i32,
                                       &mut num_cpu_info as *mut u32) == ffi::KERN_SUCCESS {
                    let proc_data = Arc::new(ProcessorData::new(cpu_info, num_cpu_info));
                    for i in 0..num_cpu {
                        let mut p = processor::create_proc(format!("{}", i + 1), Arc::clone(&proc_data));
                        let in_use = *cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize + ffi::CPU_STATE_USER as isize)
                            + *cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize + ffi::CPU_STATE_SYSTEM as isize)
                            + *cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize + ffi::CPU_STATE_NICE as isize);
                        let total = in_use + *cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize + ffi::CPU_STATE_IDLE as isize);
                        processor::set_cpu_proc(&mut p, in_use as f32 / total as f32);
                        self.processors.push(p);
                    }
                }
            } else if ffi::host_processor_info(ffi::mach_host_self(), ffi::PROCESSOR_CPU_LOAD_INFO,
                                               &mut num_cpu_u as *mut u32,
                                               &mut cpu_info as *mut *mut i32,
                                               &mut num_cpu_info as *mut u32) == ffi::KERN_SUCCESS {
                let mut pourcent = 0f32;
                let proc_data = Arc::new(ProcessorData::new(cpu_info, num_cpu_info));
                for (i, proc_) in self.processors.iter_mut().skip(1).enumerate() {
                    let old_proc_data = &*processor::get_processor_data(proc_);
                    let in_use = (*cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_USER as isize)
                            - *old_proc_data.cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_USER as isize))
                        + (*cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_SYSTEM as isize)
                            - *old_proc_data.cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_SYSTEM as isize))
                        + (*cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_NICE as isize)
                            - *old_proc_data.cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_NICE as isize));
                    let total = in_use + (*cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_IDLE as isize)
                        - *old_proc_data.cpu_info.offset((ffi::CPU_STATE_MAX * i) as isize
                            + ffi::CPU_STATE_IDLE as isize));
                    processor::update_proc(proc_, in_use as f32 / total as f32, Arc::clone(&proc_data));
                    pourcent += proc_.get_cpu_usage();
                }
                if self.processors.len() > 1 {
                    let len = self.processors.len() - 1;
                    if let Some(p) = self.processors.get_mut(0) {
                        processor::set_cpu_usage(p, pourcent / len as f32);
                    }
                }
            }
        }
    }

    fn refresh_network(&mut self) {
        network::update_network(&mut self.network);
    }

    fn refresh_processes(&mut self) {
        let count = unsafe { ffi::proc_listallpids(::std::ptr::null_mut(), 0) };
        if count < 1 {
            return
        }
        let mut pids: Vec<Pid> = Vec::with_capacity(count as usize);
        unsafe { pids.set_len(count as usize); }
        let count = count * ::std::mem::size_of::<Pid>() as i32;
        let x = unsafe { ffi::proc_listallpids(pids.as_mut_ptr() as *mut c_void, count) };

        if x < 1 || x as usize > pids.len() {
            return
        } else if pids.len() > x as usize {
            unsafe { pids.set_len(x as usize); }
        }

        let taskallinfo_size = ::std::mem::size_of::<libc::proc_taskallinfo>() as i32;
        let taskinfo_size = ::std::mem::size_of::<libc::proc_taskinfo>() as i32;
        let threadinfo_size = ::std::mem::size_of::<libc::proc_threadinfo>() as i32;

        let mut mib: [c_int; 3] = [libc::CTL_KERN, libc::KERN_ARGMAX, 0];
        let mut arg_max = 0i32;
        let mut size = ::std::mem::size_of::<c_int>();
        unsafe {
            while libc::sysctl(mib.as_mut_ptr(), 2, (&mut arg_max) as *mut i32 as *mut c_void,
                               &mut size, ::std::ptr::null_mut(), 0) == -1 {}
        }
        let entries: Vec<Process> = {
            let mut wrap = Wrap(&mut self.process_list);
            let p_wrap = &mut wrap as *mut Wrap as usize;
            pids.par_iter()
                .flat_map(|pid| {
                    let mut mib: [c_int; 3] = [libc::CTL_KERN, libc::KERN_ARGMAX, 0];
                    let mut wrap: &mut Wrap = unsafe { &mut *(p_wrap as *mut Wrap as *mut Wrap) };
                    match update_process(&mut wrap, *pid, taskallinfo_size, taskinfo_size,
                                         threadinfo_size, &mut mib, arg_max as size_t) {
                        Ok(x) => x,
                        Err(_) => None,
                    }
                })
                .collect()
        };
        entries.into_iter().for_each(|entry| {
            self.process_list.insert(entry.pid(), entry);
        });
        self.clear_procs();
    }

    fn refresh_process(&mut self, pid: Pid) -> bool {
        let taskallinfo_size = ::std::mem::size_of::<libc::proc_taskallinfo>() as i32;
        let taskinfo_size = ::std::mem::size_of::<libc::proc_taskinfo>() as i32;
        let threadinfo_size = ::std::mem::size_of::<libc::proc_threadinfo>() as i32;

        let mut mib: [c_int; 3] = [libc::CTL_KERN, libc::KERN_ARGMAX, 0];
        let mut arg_max = 0i32;
        let mut size = ::std::mem::size_of::<c_int>();
        unsafe {
            while libc::sysctl(mib.as_mut_ptr(), 2, (&mut arg_max) as *mut i32 as *mut c_void,
                               &mut size, ::std::ptr::null_mut(), 0) == -1 {}
        }
        match {
            let mut wrap = Wrap(&mut self.process_list);
            update_process(&mut wrap, pid, taskallinfo_size, taskinfo_size,
                           threadinfo_size, &mut mib, arg_max as size_t)
        } {
            Ok(Some(p)) => {
                self.process_list.insert(p.pid(), p);
                true
            }
            Ok(_) => true,
            Err(_) => false,
        }
    }

    fn refresh_disks(&mut self) {
        for disk in &mut self.disks {
            disk.update();
        }
    }

    fn refresh_disk_list(&mut self) {
        self.disks = get_disks();
    }

    // COMMON PART
    //
    // Need to be moved into a "common" file to avoid duplication.

    fn get_process_list(&self) -> &HashMap<Pid, Process> {
        &self.process_list
    }

    fn get_process(&self, pid: Pid) -> Option<&Process> {
        self.process_list.get(&pid)
    }

    fn get_processor_list(&self) -> &[Processor] {
        &self.processors[..]
    }

    fn get_network(&self) -> &NetworkData {
        &self.network
    }

    fn get_total_memory(&self) -> u64 {
        self.mem_total
    }

    fn get_free_memory(&self) -> u64 {
        self.mem_free
    }

    fn get_used_memory(&self) -> u64 {
        self.mem_total - self.mem_free
    }

    fn get_total_swap(&self) -> u64 {
        self.swap_total
    }

    fn get_free_swap(&self) -> u64 {
        self.swap_free
    }

    // need to be checked
    fn get_used_swap(&self) -> u64 {
        self.swap_total - self.swap_free
    }

    fn get_components_list(&self) -> &[Component] {
        &self.temperatures[..]
    }

    fn get_disks(&self) -> &[Disk] {
        &self.disks[..]
    }

    fn get_uptime(&self) -> u64 {
        self.uptime
    }
}

impl Default for System {
    fn default() -> System {
        System::new()
    }
}