/*
 * Copyright (c) 2009, Giampaolo Rodola'. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 *
 * FreeBSD platform-specific module methods for _psutil_bsd
 */


#include <Python.h>
#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <fcntl.h>
#include <paths.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/param.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/cpuset.h>
#include <net/route.h>

#include <sys/socket.h>
#include <sys/socketvar.h>    // for struct xsocket
#include <sys/un.h>
#include <sys/unpcb.h>
#include <sys/sockio.h>
// for xinpcb struct
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_var.h>   // for struct xtcpcb
#include <netinet/tcp_fsm.h>   // for TCP connection states
#include <arpa/inet.h>         // for inet_ntop()

#if __FreeBSD_version < 900000
#include <utmp.h>         // system users
#else
#include <utmpx.h>
#endif
#include <devstat.h>      // get io counters
#include <sys/vmmeter.h>  // needed for vmtotal struct
#include <libutil.h>      // process open files, shared libs (kinfo_getvmmap)
#include <sys/mount.h>

#include <net/if.h>       // net io counters
#include <net/if_dl.h>
#include <net/route.h>
#include <net/if_media.h>

#include <netinet/in.h>   // process open files/connections
#include <sys/un.h>

#include "_psutil_bsd.h"
#include "_psutil_common.h"
#include "arch/bsd/process_info.h"


// convert a timeval struct to a double
#define TV2DOUBLE(t)    ((t).tv_sec + (t).tv_usec / 1000000.0)


/*
 * Utility function which fills a kinfo_proc struct based on process pid
 */
static int
psutil_kinfo_proc(const pid_t pid, struct kinfo_proc *proc)
{
    int mib[4];
    size_t size;
    mib[0] = CTL_KERN;
    mib[1] = KERN_PROC;
    mib[2] = KERN_PROC_PID;
    mib[3] = pid;

    size = sizeof(struct kinfo_proc);

    if (sysctl((int *)mib, 4, proc, &size, NULL, 0) == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        return -1;
    }

    // sysctl stores 0 in the size if we can't find the process information.
    if (size == 0) {
        NoSuchProcess();
        return -1;
    }
    return 0;
}


/*
 * Set exception to AccessDenied if pid exists else NoSuchProcess.
 */
void
psutil_raise_ad_or_nsp(long pid) {
    if (psutil_pid_exists(pid) == 0)
        NoSuchProcess();
    else
        AccessDenied();
}


/*
 * Return a Python list of all the PIDs running on the system.
 */
static PyObject *
psutil_pids(PyObject *self, PyObject *args)
{
    kinfo_proc *proclist = NULL;
    kinfo_proc *orig_address = NULL;
    size_t num_processes;
    size_t idx;
    PyObject *retlist = PyList_New(0);
    PyObject *pid = NULL;

    if (retlist == NULL)
        return NULL;
    if (psutil_get_proc_list(&proclist, &num_processes) != 0) {
        PyErr_SetString(PyExc_RuntimeError,
                        "failed to retrieve process list.");
        goto error;
    }

    if (num_processes > 0) {
        orig_address = proclist; // save so we can free it after we're done
        for (idx = 0; idx < num_processes; idx++) {
            pid = Py_BuildValue("i", proclist->ki_pid);
            if (!pid)
                goto error;
            if (PyList_Append(retlist, pid))
                goto error;
            Py_DECREF(pid);
            proclist++;
        }
        free(orig_address);
    }

    return retlist;

error:
    Py_XDECREF(pid);
    Py_DECREF(retlist);
    if (orig_address != NULL)
        free(orig_address);
    return NULL;
}


/*
 * Return a Python float indicating the system boot time expressed in
 * seconds since the epoch.
 */
static PyObject *
psutil_boot_time(PyObject *self, PyObject *args)
{
    // fetch sysctl "kern.boottime"
    static int request[2] = { CTL_KERN, KERN_BOOTTIME };
    struct timeval boottime;
    size_t len = sizeof(boottime);

    if (sysctl(request, 2, &boottime, &len, NULL, 0) == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    return Py_BuildValue("d", (double)boottime.tv_sec);
}


/*
 * Return process name from kinfo_proc as a Python string.
 */
static PyObject *
psutil_proc_name(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("s", kp.ki_comm);
}


/*
 * Return process pathname executable.
 * Thanks to Robert N. M. Watson:
 * http://fxr.googlebit.com/source/usr.bin/procstat/procstat_bin.c?v=8-CURRENT
 */
static PyObject *
psutil_proc_exe(PyObject *self, PyObject *args)
{
    long pid;
    char pathname[PATH_MAX];
    int error;
    int mib[4];
    size_t size;

    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;

    mib[0] = CTL_KERN;
    mib[1] = KERN_PROC;
    mib[2] = KERN_PROC_PATHNAME;
    mib[3] = pid;

    size = sizeof(pathname);
    error = sysctl(mib, 4, pathname, &size, NULL, 0);
    if (error == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    if (size == 0 || strlen(pathname) == 0) {
        if (psutil_pid_exists(pid) == 0)
            return NoSuchProcess();
        else
            strcpy(pathname, "");
    }
    return Py_BuildValue("s", pathname);
}


/*
 * Return process cmdline as a Python list of cmdline arguments.
 */
static PyObject *
psutil_proc_cmdline(PyObject *self, PyObject *args)
{
    long pid;
    PyObject *arglist = NULL;

    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;

    // get the commandline, defined in arch/bsd/process_info.c
    arglist = psutil_get_arg_list(pid);

    // psutil_get_arg_list() returns NULL only if psutil_cmd_args
    // failed with ESRCH (no process with that PID)
    if (NULL == arglist)
        return PyErr_SetFromErrno(PyExc_OSError);
    return Py_BuildValue("N", arglist);
}


/*
 * Return process parent pid from kinfo_proc as a Python integer.
 */
static PyObject *
psutil_proc_ppid(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("l", (long)kp.ki_ppid);
}


/*
 * Return process status as a Python integer.
 */
static PyObject *
psutil_proc_status(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("i", (int)kp.ki_stat);
}


/*
 * Return process real, effective and saved user ids from kinfo_proc
 * as a Python tuple.
 */
static PyObject *
psutil_proc_uids(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("lll",
                         (long)kp.ki_ruid,
                         (long)kp.ki_uid,
                         (long)kp.ki_svuid);
}


/*
 * Return process real, effective and saved group ids from kinfo_proc
 * as a Python tuple.
 */
static PyObject *
psutil_proc_gids(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("lll",
                         (long)kp.ki_rgid,
                         (long)kp.ki_groups[0],
                         (long)kp.ki_svuid);
}


/*
 * Return process real, effective and saved group ids from kinfo_proc
 * as a Python tuple.
 */
static PyObject *
psutil_proc_tty_nr(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("i", kp.ki_tdev);
}


/*
 * Return the number of context switches performed by process as a tuple.
 */
static PyObject *
psutil_proc_num_ctx_switches(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("(ll)",
                         kp.ki_rusage.ru_nvcsw,
                         kp.ki_rusage.ru_nivcsw);
}


/*
 * Return number of threads used by process as a Python integer.
 */
static PyObject *
psutil_proc_num_threads(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("l", (long)kp.ki_numthreads);
}


/*
 * Retrieves all threads used by process returning a list of tuples
 * including thread id, user time and system time.
 * Thanks to Robert N. M. Watson:
 * http://fxr.googlebit.com/source/usr.bin/procstat/
 *     procstat_threads.c?v=8-CURRENT
 */
static PyObject *
psutil_proc_threads(PyObject *self, PyObject *args)
{
    long pid;
    int mib[4];
    struct kinfo_proc *kip = NULL;
    struct kinfo_proc *kipp = NULL;
    int error;
    unsigned int i;
    size_t size;
    PyObject *retList = PyList_New(0);
    PyObject *pyTuple = NULL;

    if (retList == NULL)
        return NULL;
    if (! PyArg_ParseTuple(args, "l", &pid))
        goto error;

    // we need to re-query for thread information, so don't use *kipp
    mib[0] = CTL_KERN;
    mib[1] = KERN_PROC;
    mib[2] = KERN_PROC_PID | KERN_PROC_INC_THREAD;
    mib[3] = pid;

    size = 0;
    error = sysctl(mib, 4, NULL, &size, NULL, 0);
    if (error == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }
    if (size == 0) {
        NoSuchProcess();
        goto error;
    }

    kip = malloc(size);
    if (kip == NULL) {
        PyErr_NoMemory();
        goto error;
    }

    error = sysctl(mib, 4, kip, &size, NULL, 0);
    if (error == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }
    if (size == 0) {
        NoSuchProcess();
        goto error;
    }

    for (i = 0; i < size / sizeof(*kipp); i++) {
        kipp = &kip[i];
        pyTuple = Py_BuildValue("Idd",
                                kipp->ki_tid,
                                TV2DOUBLE(kipp->ki_rusage.ru_utime),
                                TV2DOUBLE(kipp->ki_rusage.ru_stime));
        if (pyTuple == NULL)
            goto error;
        if (PyList_Append(retList, pyTuple))
            goto error;
        Py_DECREF(pyTuple);
    }
    free(kip);
    return retList;

error:
    Py_XDECREF(pyTuple);
    Py_DECREF(retList);
    if (kip != NULL)
        free(kip);
    return NULL;
}


/*
 * Return a Python tuple (user_time, kernel_time)
 */
static PyObject *
psutil_proc_cpu_times(PyObject *self, PyObject *args)
{
    long pid;
    double user_t, sys_t;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    // convert from microseconds to seconds
    user_t = TV2DOUBLE(kp.ki_rusage.ru_utime);
    sys_t = TV2DOUBLE(kp.ki_rusage.ru_stime);
    return Py_BuildValue("(dd)", user_t, sys_t);
}


/*
 * Return the number of logical CPUs in the system.
 * XXX this could be shared with OSX
 */
static PyObject *
psutil_cpu_count_logical(PyObject *self, PyObject *args)
{
    int mib[2];
    int ncpu;
    size_t len;

    mib[0] = CTL_HW;
    mib[1] = HW_NCPU;
    len = sizeof(ncpu);

    if (sysctl(mib, 2, &ncpu, &len, NULL, 0) == -1)
        Py_RETURN_NONE;  // mimic os.cpu_count()
    else
        return Py_BuildValue("i", ncpu);
}


/*
 * Return an XML string from which we'll determine the number of
 * physical CPU cores in the system.
 */
static PyObject *
psutil_cpu_count_phys(PyObject *self, PyObject *args)
{
    void *topology = NULL;
    size_t size = 0;
    PyObject *py_str;

    if (sysctlbyname("kern.sched.topology_spec", NULL, &size, NULL, 0))
        goto error;

    topology = malloc(size);
    if (!topology) {
        PyErr_NoMemory();
        return NULL;
    }

    if (sysctlbyname("kern.sched.topology_spec", topology, &size, NULL, 0))
        goto error;

    py_str = Py_BuildValue("s", topology);
    free(topology);
    return py_str;

error:
    if (topology != NULL)
        free(topology);
    Py_RETURN_NONE;
}


/*
 * Return a Python float indicating the process create time expressed in
 * seconds since the epoch.
 */
static PyObject *
psutil_proc_create_time(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("d", TV2DOUBLE(kp.ki_start));
}


/*
 * Return a Python float indicating the process create time expressed in
 * seconds since the epoch.
 */
static PyObject *
psutil_proc_io_counters(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    // there's apparently no way to determine bytes count, hence return -1.
    return Py_BuildValue("(llll)",
                         kp.ki_rusage.ru_inblock,
                         kp.ki_rusage.ru_oublock,
                         -1,
                         -1);
}


/*
 * Return extended memory info for a process as a Python tuple.
 */
static PyObject *
psutil_proc_memory_info(PyObject *self, PyObject *args)
{
    long pid;
    struct kinfo_proc kp;
    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        return NULL;
    return Py_BuildValue("(lllll)",
                         ptoa(kp.ki_rssize),    // rss
                         (long)kp.ki_size,      // vms
                         ptoa(kp.ki_tsize),     // text
                         ptoa(kp.ki_dsize),     // data
                         ptoa(kp.ki_ssize));    // stack
}


/*
 * Return virtual memory usage statistics.
 */
static PyObject *
psutil_virtual_mem(PyObject *self, PyObject *args)
{
    unsigned int   total, active, inactive, wired, cached, free;
    size_t         size = sizeof(total);
    struct vmtotal vm;
    int            mib[] = {CTL_VM, VM_METER};
    long           pagesize = getpagesize();
#if __FreeBSD_version > 702101
    long buffers;
#else
    int buffers;
#endif
    size_t buffers_size = sizeof(buffers);

    if (sysctlbyname("vm.stats.vm.v_page_count", &total, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vm.stats.vm.v_active_count", &active, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vm.stats.vm.v_inactive_count",
                     &inactive, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vm.stats.vm.v_wire_count", &wired, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vm.stats.vm.v_cache_count", &cached, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vm.stats.vm.v_free_count", &free, &size, NULL, 0))
        goto error;
    if (sysctlbyname("vfs.bufspace", &buffers, &buffers_size, NULL, 0))
        goto error;

    size = sizeof(vm);
    if (sysctl(mib, 2, &vm, &size, NULL, 0) != 0)
        goto error;

    return Py_BuildValue("KKKKKKKK",
        (unsigned long long) total    * pagesize,
        (unsigned long long) free     * pagesize,
        (unsigned long long) active   * pagesize,
        (unsigned long long) inactive * pagesize,
        (unsigned long long) wired    * pagesize,
        (unsigned long long) cached   * pagesize,
        (unsigned long long) buffers,
        (unsigned long long) (vm.t_vmshr + vm.t_rmshr) * pagesize  // shared
    );

error:
    PyErr_SetFromErrno(PyExc_OSError);
    return NULL;
}


#ifndef _PATH_DEVNULL
#define _PATH_DEVNULL "/dev/null"
#endif

/*
 * Return swap memory stats (see 'swapinfo' cmdline tool)
 */
static PyObject *
psutil_swap_mem(PyObject *self, PyObject *args)
{
    kvm_t *kd;
    struct kvm_swap kvmsw[1];
    unsigned int swapin, swapout, nodein, nodeout;
    size_t size = sizeof(unsigned int);

    kd = kvm_open(NULL, _PATH_DEVNULL, NULL, O_RDONLY, "kvm_open failed");
    if (kd == NULL) {
        PyErr_SetString(PyExc_RuntimeError, "kvm_open failed");
        return NULL;
    }

    if (kvm_getswapinfo(kd, kvmsw, 1, 0) < 0) {
        kvm_close(kd);
        PyErr_SetString(PyExc_RuntimeError, "kvm_getswapinfo failed");
        return NULL;
    }

    kvm_close(kd);

    if (sysctlbyname("vm.stats.vm.v_swapin", &swapin, &size, NULL, 0) == -1)
        goto sbn_error;
    if (sysctlbyname("vm.stats.vm.v_swapout", &swapout, &size, NULL, 0) == -1)
        goto sbn_error;
    if (sysctlbyname("vm.stats.vm.v_vnodein", &nodein, &size, NULL, 0) == -1)
        goto sbn_error;
    if (sysctlbyname("vm.stats.vm.v_vnodeout", &nodeout, &size, NULL, 0) == -1)
        goto sbn_error;

    return Py_BuildValue("(iiiII)",
                         kvmsw[0].ksw_total,                     // total
                         kvmsw[0].ksw_used,                      // used
                         kvmsw[0].ksw_total - kvmsw[0].ksw_used, // free
                         swapin + swapout,                       // swap in
                         nodein + nodeout);                      // swap out

sbn_error:
    PyErr_SetFromErrno(PyExc_OSError);
    return NULL;
}


/*
 * Return a Python tuple representing user, kernel and idle CPU times
 */
static PyObject *
psutil_cpu_times(PyObject *self, PyObject *args)
{
    long cpu_time[CPUSTATES];
    size_t size;

    size = sizeof(cpu_time);

    if (sysctlbyname("kern.cp_time", &cpu_time, &size, NULL, 0) == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }

    return Py_BuildValue("(ddddd)",
                         (double)cpu_time[CP_USER] / CLOCKS_PER_SEC,
                         (double)cpu_time[CP_NICE] / CLOCKS_PER_SEC,
                         (double)cpu_time[CP_SYS] / CLOCKS_PER_SEC,
                         (double)cpu_time[CP_IDLE] / CLOCKS_PER_SEC,
                         (double)cpu_time[CP_INTR] / CLOCKS_PER_SEC
                        );
}


/*
 * XXX
 * These functions are available on FreeBSD 8 only.
 * In the upper python layer we do various tricks to avoid crashing
 * and/or to provide alternatives where possible.
 */


#if defined(__FreeBSD_version) && __FreeBSD_version >= 800000
/*
 * Return files opened by process as a list of (path, fd) tuples.
 * TODO: this is broken as it may report empty paths. 'procstat'
 * utility has the same problem see:
 * https://github.com/giampaolo/psutil/issues/595
 */
static PyObject *
psutil_proc_open_files(PyObject *self, PyObject *args)
{
    long pid;
    int i, cnt;
    struct kinfo_file *freep = NULL;
    struct kinfo_file *kif;
    struct kinfo_proc kipp;
    PyObject *retList = PyList_New(0);
    PyObject *tuple = NULL;

    if (retList == NULL)
        return NULL;
    if (! PyArg_ParseTuple(args, "l", &pid))
        goto error;
    if (psutil_kinfo_proc(pid, &kipp) == -1)
        goto error;

    freep = kinfo_getfile(pid, &cnt);
    if (freep == NULL) {
        psutil_raise_ad_or_nsp(pid);
        goto error;
    }

    for (i = 0; i < cnt; i++) {
        kif = &freep[i];
        if ((kif->kf_type == KF_TYPE_VNODE) &&
                (kif->kf_vnode_type == KF_VTYPE_VREG))
        {
            tuple = Py_BuildValue("(si)", kif->kf_path, kif->kf_fd);
            if (tuple == NULL)
                goto error;
            if (PyList_Append(retList, tuple))
                goto error;
            Py_DECREF(tuple);
        }
    }
    free(freep);
    return retList;

error:
    Py_XDECREF(tuple);
    Py_DECREF(retList);
    if (freep != NULL)
        free(freep);
    return NULL;
}


/*
 * Return files opened by process as a list of (path, fd) tuples
 */
static PyObject *
psutil_proc_num_fds(PyObject *self, PyObject *args)
{
    long pid;
    int cnt;

    struct kinfo_file *freep;
    struct kinfo_proc kipp;

    if (! PyArg_ParseTuple(args, "l", &pid))
        return NULL;
    if (psutil_kinfo_proc(pid, &kipp) == -1)
        return NULL;

    freep = kinfo_getfile(pid, &cnt);
    if (freep == NULL) {
        psutil_raise_ad_or_nsp(pid);
        return NULL;
    }
    free(freep);

    return Py_BuildValue("i", cnt);
}


/*
 * Return process current working directory.
 */
static PyObject *
psutil_proc_cwd(PyObject *self, PyObject *args)
{
    long pid;
    PyObject *path = NULL;
    struct kinfo_file *freep = NULL;
    struct kinfo_file *kif;
    struct kinfo_proc kipp;

    int i, cnt;

    if (! PyArg_ParseTuple(args, "l", &pid))
        goto error;
    if (psutil_kinfo_proc(pid, &kipp) == -1)
        goto error;

    freep = kinfo_getfile(pid, &cnt);
    if (freep == NULL) {
        psutil_raise_ad_or_nsp(pid);
        goto error;
    }

    for (i = 0; i < cnt; i++) {
        kif = &freep[i];
        if (kif->kf_fd == KF_FD_TYPE_CWD) {
            path = Py_BuildValue("s", kif->kf_path);
            if (!path)
                goto error;
            break;
        }
    }
    /*
     * For lower pids it seems we can't retrieve any information
     * (lsof can't do that it either).  Since this happens even
     * as root we return an empty string instead of AccessDenied.
     */
    if (path == NULL)
        path = Py_BuildValue("s", "");
    free(freep);
    return path;

error:
    Py_XDECREF(path);
    if (freep != NULL)
        free(freep);
    return NULL;
}


// The tcplist fetching and walking is borrowed from netstat/inet.c.
static char *
psutil_fetch_tcplist(void)
{
    char *buf;
    size_t len;

    for (;;) {
        if (sysctlbyname("net.inet.tcp.pcblist", NULL, &len, NULL, 0) < 0) {
            PyErr_SetFromErrno(PyExc_OSError);
            return NULL;
        }
        buf = malloc(len);
        if (buf == NULL) {
            PyErr_NoMemory();
            return NULL;
        }
        if (sysctlbyname("net.inet.tcp.pcblist", buf, &len, NULL, 0) < 0) {
            free(buf);
            PyErr_SetFromErrno(PyExc_OSError);
            return NULL;
        }
        return buf;
    }
}

static int
psutil_sockaddr_port(int family, struct sockaddr_storage *ss)
{
    struct sockaddr_in6 *sin6;
    struct sockaddr_in *sin;

    if (family == AF_INET) {
        sin = (struct sockaddr_in *)ss;
        return (sin->sin_port);
    }
    else {
        sin6 = (struct sockaddr_in6 *)ss;
        return (sin6->sin6_port);
    }
}

static void *
psutil_sockaddr_addr(int family, struct sockaddr_storage *ss)
{
    struct sockaddr_in6 *sin6;
    struct sockaddr_in *sin;

    if (family == AF_INET) {
        sin = (struct sockaddr_in *)ss;
        return (&sin->sin_addr);
    }
    else {
        sin6 = (struct sockaddr_in6 *)ss;
        return (&sin6->sin6_addr);
    }
}

static socklen_t
psutil_sockaddr_addrlen(int family)
{
    if (family == AF_INET)
        return (sizeof(struct in_addr));
    else
        return (sizeof(struct in6_addr));
}

static int
psutil_sockaddr_matches(int family, int port, void *pcb_addr,
                        struct sockaddr_storage *ss)
{
    if (psutil_sockaddr_port(family, ss) != port)
        return (0);
    return (memcmp(psutil_sockaddr_addr(family, ss), pcb_addr,
                   psutil_sockaddr_addrlen(family)) == 0);
}

static struct tcpcb *
psutil_search_tcplist(char *buf, struct kinfo_file *kif)
{
    struct tcpcb *tp;
    struct inpcb *inp;
    struct xinpgen *xig, *oxig;
    struct xsocket *so;

    oxig = xig = (struct xinpgen *)buf;
    for (xig = (struct xinpgen *)((char *)xig + xig->xig_len);
            xig->xig_len > sizeof(struct xinpgen);
            xig = (struct xinpgen *)((char *)xig + xig->xig_len)) {
        tp = &((struct xtcpcb *)xig)->xt_tp;
        inp = &((struct xtcpcb *)xig)->xt_inp;
        so = &((struct xtcpcb *)xig)->xt_socket;

        if (so->so_type != kif->kf_sock_type ||
                so->xso_family != kif->kf_sock_domain ||
                so->xso_protocol != kif->kf_sock_protocol)
            continue;

        if (kif->kf_sock_domain == AF_INET) {
            if (!psutil_sockaddr_matches(
                    AF_INET, inp->inp_lport, &inp->inp_laddr,
                    &kif->kf_sa_local))
                continue;
            if (!psutil_sockaddr_matches(
                    AF_INET, inp->inp_fport, &inp->inp_faddr,
                    &kif->kf_sa_peer))
                continue;
        } else {
            if (!psutil_sockaddr_matches(
                    AF_INET6, inp->inp_lport, &inp->in6p_laddr,
                    &kif->kf_sa_local))
                continue;
            if (!psutil_sockaddr_matches(
                    AF_INET6, inp->inp_fport, &inp->in6p_faddr,
                    &kif->kf_sa_peer))
                continue;
        }

        return (tp);
    }
    return NULL;
}


// a signaler for connections without an actual status
static int PSUTIL_CONN_NONE = 128;

/*
 * Return connections opened by process.
 */
static PyObject *
psutil_proc_connections(PyObject *self, PyObject *args)
{
    long pid;
    int i, cnt;

    struct kinfo_file *freep = NULL;
    struct kinfo_file *kif;
    char *tcplist = NULL;
    struct tcpcb *tcp;

    PyObject *retList = PyList_New(0);
    PyObject *tuple = NULL;
    PyObject *laddr = NULL;
    PyObject *raddr = NULL;
    PyObject *af_filter = NULL;
    PyObject *type_filter = NULL;
    PyObject *_family = NULL;
    PyObject *_type = NULL;

    if (retList == NULL)
        return NULL;
    if (! PyArg_ParseTuple(args, "lOO", &pid, &af_filter, &type_filter))
        goto error;
    if (!PySequence_Check(af_filter) || !PySequence_Check(type_filter)) {
        PyErr_SetString(PyExc_TypeError, "arg 2 or 3 is not a sequence");
        goto error;
    }

    freep = kinfo_getfile(pid, &cnt);
    if (freep == NULL) {
        psutil_raise_ad_or_nsp(pid);
        goto error;
    }

    tcplist = psutil_fetch_tcplist();
    if (tcplist == NULL) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    for (i = 0; i < cnt; i++) {
        int lport, rport, state;
        char lip[200], rip[200];
        char path[PATH_MAX];
        int inseq;
        tuple = NULL;
        laddr = NULL;
        raddr = NULL;

        kif = &freep[i];
        if (kif->kf_type == KF_TYPE_SOCKET) {
            // apply filters
            _family = PyLong_FromLong((long)kif->kf_sock_domain);
            inseq = PySequence_Contains(af_filter, _family);
            Py_DECREF(_family);
            if (inseq == 0)
                continue;
            _type = PyLong_FromLong((long)kif->kf_sock_type);
            inseq = PySequence_Contains(type_filter, _type);
            Py_DECREF(_type);
            if (inseq == 0)
                continue;
            // IPv4 / IPv6 socket
            if ((kif->kf_sock_domain == AF_INET) ||
                    (kif->kf_sock_domain == AF_INET6)) {
                // fill status
                state = PSUTIL_CONN_NONE;
                if (kif->kf_sock_type == SOCK_STREAM) {
                    tcp = psutil_search_tcplist(tcplist, kif);
                    if (tcp != NULL)
                        state = (int)tcp->t_state;
                }

                // build addr and port
                inet_ntop(
                    kif->kf_sock_domain,
                    psutil_sockaddr_addr(kif->kf_sock_domain,
                                         &kif->kf_sa_local),
                    lip,
                    sizeof(lip));
                inet_ntop(
                    kif->kf_sock_domain,
                    psutil_sockaddr_addr(kif->kf_sock_domain,
                                         &kif->kf_sa_peer),
                    rip,
                    sizeof(rip));
                lport = htons(psutil_sockaddr_port(kif->kf_sock_domain,
                                                   &kif->kf_sa_local));
                rport = htons(psutil_sockaddr_port(kif->kf_sock_domain,
                                                   &kif->kf_sa_peer));

                // construct python tuple/list
                laddr = Py_BuildValue("(si)", lip, lport);
                if (!laddr)
                    goto error;
                if (rport != 0)
                    raddr = Py_BuildValue("(si)", rip, rport);
                else
                    raddr = Py_BuildValue("()");
                if (!raddr)
                    goto error;
                tuple = Py_BuildValue("(iiiNNi)",
                                      kif->kf_fd,
                                      kif->kf_sock_domain,
                                      kif->kf_sock_type,
                                      laddr,
                                      raddr,
                                      state);
                if (!tuple)
                    goto error;
                if (PyList_Append(retList, tuple))
                    goto error;
                Py_DECREF(tuple);
            }
            // UNIX socket
            else if (kif->kf_sock_domain == AF_UNIX) {
                struct sockaddr_un *sun;

                sun = (struct sockaddr_un *)&kif->kf_sa_local;
                snprintf(
                    path, sizeof(path), "%.*s",
                    (int)(sun->sun_len - (sizeof(*sun) - sizeof(sun->sun_path))),
                    sun->sun_path);

                tuple = Py_BuildValue("(iiisOi)",
                                      kif->kf_fd,
                                      kif->kf_sock_domain,
                                      kif->kf_sock_type,
                                      path,
                                      Py_None,
                                      PSUTIL_CONN_NONE);
                if (!tuple)
                    goto error;
                if (PyList_Append(retList, tuple))
                    goto error;
                Py_DECREF(tuple);
                Py_INCREF(Py_None);
            }
        }
    }
    free(freep);
    free(tcplist);
    return retList;

error:
    Py_XDECREF(tuple);
    Py_XDECREF(laddr);
    Py_XDECREF(raddr);
    Py_DECREF(retList);
    if (freep != NULL)
        free(freep);
    if (tcplist != NULL)
        free(tcplist);
    return NULL;
}


/*
 * Return a Python list of tuple representing per-cpu times
 */
static PyObject *
psutil_per_cpu_times(PyObject *self, PyObject *args)
{
    static int maxcpus;
    int mib[2];
    int ncpu;
    size_t len;
    size_t size;
    int i;
    PyObject *py_retlist = PyList_New(0);
    PyObject *py_cputime = NULL;

    if (py_retlist == NULL)
        return NULL;

    // retrieve maxcpus value
    size = sizeof(maxcpus);
    if (sysctlbyname("kern.smp.maxcpus", &maxcpus, &size, NULL, 0) < 0) {
        Py_DECREF(py_retlist);
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    long cpu_time[maxcpus][CPUSTATES];

    // retrieve the number of cpus
    mib[0] = CTL_HW;
    mib[1] = HW_NCPU;
    len = sizeof(ncpu);
    if (sysctl(mib, 2, &ncpu, &len, NULL, 0) == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    // per-cpu info
    size = sizeof(cpu_time);
    if (sysctlbyname("kern.cp_times", &cpu_time, &size, NULL, 0) == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    for (i = 0; i < ncpu; i++) {
        py_cputime = Py_BuildValue(
            "(ddddd)",
            (double)cpu_time[i][CP_USER] / CLOCKS_PER_SEC,
            (double)cpu_time[i][CP_NICE] / CLOCKS_PER_SEC,
            (double)cpu_time[i][CP_SYS] / CLOCKS_PER_SEC,
            (double)cpu_time[i][CP_IDLE] / CLOCKS_PER_SEC,
            (double)cpu_time[i][CP_INTR] / CLOCKS_PER_SEC);
        if (!py_cputime)
            goto error;
        if (PyList_Append(py_retlist, py_cputime))
            goto error;
        Py_DECREF(py_cputime);
    }

    return py_retlist;

error:
    Py_XDECREF(py_cputime);
    Py_DECREF(py_retlist);
    return NULL;
}


// remove spaces from string
void remove_spaces(char *str) {
    char *p1 = str;
    char *p2 = str;
    do
        while (*p2 == ' ')
            p2++;
    while ((*p1++ = *p2++));
}


/*
 * Return a list of tuples for every process memory maps.
 * 'procstat' cmdline utility has been used as an example.
 */
static PyObject *
psutil_proc_memory_maps(PyObject *self, PyObject *args)
{
    long pid;
    int ptrwidth;
    int i, cnt;
    char addr[1000];
    char perms[4];
    const char *path;
    struct kinfo_proc kp;
    struct kinfo_vmentry *freep = NULL;
    struct kinfo_vmentry *kve;
    ptrwidth = 2 * sizeof(void *);
    PyObject *pytuple = NULL;
    PyObject *retlist = PyList_New(0);

    if (retlist == NULL)
        return NULL;
    if (! PyArg_ParseTuple(args, "l", &pid))
        goto error;
    if (psutil_kinfo_proc(pid, &kp) == -1)
        goto error;

    freep = kinfo_getvmmap(pid, &cnt);
    if (freep == NULL) {
        psutil_raise_ad_or_nsp(pid);
        goto error;
    }
    for (i = 0; i < cnt; i++) {
        pytuple = NULL;
        kve = &freep[i];
        addr[0] = '\0';
        perms[0] = '\0';
        sprintf(addr, "%#*jx-%#*jx", ptrwidth, (uintmax_t)kve->kve_start,
                ptrwidth, (uintmax_t)kve->kve_end);
        remove_spaces(addr);
        strlcat(perms, kve->kve_protection & KVME_PROT_READ ? "r" : "-",
                sizeof(perms));
        strlcat(perms, kve->kve_protection & KVME_PROT_WRITE ? "w" : "-",
                sizeof(perms));
        strlcat(perms, kve->kve_protection & KVME_PROT_EXEC ? "x" : "-",
                sizeof(perms));

        if (strlen(kve->kve_path) == 0) {
            switch (kve->kve_type) {
                case KVME_TYPE_NONE:
                    path = "[none]";
                    break;
                case KVME_TYPE_DEFAULT:
                    path = "[default]";
                    break;
                case KVME_TYPE_VNODE:
                    path = "[vnode]";
                    break;
                case KVME_TYPE_SWAP:
                    path = "[swap]";
                    break;
                case KVME_TYPE_DEVICE:
                    path = "[device]";
                    break;
                case KVME_TYPE_PHYS:
                    path = "[phys]";
                    break;
                case KVME_TYPE_DEAD:
                    path = "[dead]";
                    break;
                case KVME_TYPE_SG:
                    path = "[sg]";
                    break;
                case KVME_TYPE_UNKNOWN:
                    path = "[unknown]";
                    break;
                default:
                    path = "[?]";
                    break;
            }
        }
        else {
            path = kve->kve_path;
        }

        pytuple = Py_BuildValue("sssiiii",
            addr,                       // "start-end" address
            perms,                      // "rwx" permissions
            path,                       // path
            kve->kve_resident,          // rss
            kve->kve_private_resident,  // private
            kve->kve_ref_count,         // ref count
            kve->kve_shadow_count);     // shadow count
        if (!pytuple)
            goto error;
        if (PyList_Append(retlist, pytuple))
            goto error;
        Py_DECREF(pytuple);
    }
    free(freep);
    return retlist;

error:
    Py_XDECREF(pytuple);
    Py_DECREF(retlist);
    if (freep != NULL)
        free(freep);
    return NULL;
}
#endif


/*
 * Return a list of tuples including device, mount point and fs type
 * for all partitions mounted on the system.
 */
static PyObject *
psutil_disk_partitions(PyObject *self, PyObject *args)
{
    int num;
    int i;
    long len;
    uint64_t flags;
    char opts[200];
    struct statfs *fs = NULL;
    PyObject *py_retlist = PyList_New(0);
    PyObject *py_tuple = NULL;

    if (py_retlist == NULL)
        return NULL;

    // get the number of mount points
    Py_BEGIN_ALLOW_THREADS
    num = getfsstat(NULL, 0, MNT_NOWAIT);
    Py_END_ALLOW_THREADS
    if (num == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    len = sizeof(*fs) * num;
    fs = malloc(len);
    if (fs == NULL) {
        PyErr_NoMemory();
        goto error;
    }

    Py_BEGIN_ALLOW_THREADS
    num = getfsstat(fs, len, MNT_NOWAIT);
    Py_END_ALLOW_THREADS
    if (num == -1) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    for (i = 0; i < num; i++) {
        py_tuple = NULL;
        opts[0] = 0;
        flags = fs[i].f_flags;

        // see sys/mount.h
        if (flags & MNT_RDONLY)
            strlcat(opts, "ro", sizeof(opts));
        else
            strlcat(opts, "rw", sizeof(opts));
        if (flags & MNT_SYNCHRONOUS)
            strlcat(opts, ",sync", sizeof(opts));
        if (flags & MNT_NOEXEC)
            strlcat(opts, ",noexec", sizeof(opts));
        if (flags & MNT_NOSUID)
            strlcat(opts, ",nosuid", sizeof(opts));
        if (flags & MNT_UNION)
            strlcat(opts, ",union", sizeof(opts));
        if (flags & MNT_ASYNC)
            strlcat(opts, ",async", sizeof(opts));
        if (flags & MNT_SUIDDIR)
            strlcat(opts, ",suiddir", sizeof(opts));
        if (flags & MNT_SOFTDEP)
            strlcat(opts, ",softdep", sizeof(opts));
        if (flags & MNT_NOSYMFOLLOW)
            strlcat(opts, ",nosymfollow", sizeof(opts));
        if (flags & MNT_GJOURNAL)
            strlcat(opts, ",gjournal", sizeof(opts));
        if (flags & MNT_MULTILABEL)
            strlcat(opts, ",multilabel", sizeof(opts));
        if (flags & MNT_ACLS)
            strlcat(opts, ",acls", sizeof(opts));
        if (flags & MNT_NOATIME)
            strlcat(opts, ",noatime", sizeof(opts));
        if (flags & MNT_NOCLUSTERR)
            strlcat(opts, ",noclusterr", sizeof(opts));
        if (flags & MNT_NOCLUSTERW)
            strlcat(opts, ",noclusterw", sizeof(opts));
        if (flags & MNT_NFS4ACLS)
            strlcat(opts, ",nfs4acls", sizeof(opts));

        py_tuple = Py_BuildValue("(ssss)",
                                 fs[i].f_mntfromname,  // device
                                 fs[i].f_mntonname,    // mount point
                                 fs[i].f_fstypename,   // fs type
                                 opts);                // options
        if (!py_tuple)
            goto error;
        if (PyList_Append(py_retlist, py_tuple))
            goto error;
        Py_DECREF(py_tuple);
    }

    free(fs);
    return py_retlist;

error:
    Py_XDECREF(py_tuple);
    Py_DECREF(py_retlist);
    if (fs != NULL)
        free(fs);
    return NULL;
}


/*
 * Return a Python list of named tuples with overall network I/O information
 */
static PyObject *
psutil_net_io_counters(PyObject *self, PyObject *args)
{
    char *buf = NULL, *lim, *next;
    struct if_msghdr *ifm;
    int mib[6];
    size_t len;
    PyObject *py_retdict = PyDict_New();
    PyObject *py_ifc_info = NULL;

    if (py_retdict == NULL)
        return NULL;
    mib[0] = CTL_NET;          // networking subsystem
    mib[1] = PF_ROUTE;         // type of information
    mib[2] = 0;                // protocol (IPPROTO_xxx)
    mib[3] = 0;                // address family
    mib[4] = NET_RT_IFLIST;   // operation
    mib[5] = 0;

    if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    buf = malloc(len);
    if (buf == NULL) {
        PyErr_NoMemory();
        goto error;
    }

    if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    lim = buf + len;

    for (next = buf; next < lim; ) {
        py_ifc_info = NULL;
        ifm = (struct if_msghdr *)next;
        next += ifm->ifm_msglen;

        if (ifm->ifm_type == RTM_IFINFO) {
            struct if_msghdr *if2m = (struct if_msghdr *)ifm;
            struct sockaddr_dl *sdl = (struct sockaddr_dl *)(if2m + 1);
            char ifc_name[32];

            strncpy(ifc_name, sdl->sdl_data, sdl->sdl_nlen);
            ifc_name[sdl->sdl_nlen] = 0;
            // XXX: ignore usbus interfaces:
            // http://lists.freebsd.org/pipermail/freebsd-current/
            //     2011-October/028752.html
            // 'ifconfig -a' doesn't show them, nor do we.
            if (strncmp(ifc_name, "usbus", 5) == 0)
                continue;

            py_ifc_info = Py_BuildValue("(kkkkkkki)",
                                        if2m->ifm_data.ifi_obytes,
                                        if2m->ifm_data.ifi_ibytes,
                                        if2m->ifm_data.ifi_opackets,
                                        if2m->ifm_data.ifi_ipackets,
                                        if2m->ifm_data.ifi_ierrors,
                                        if2m->ifm_data.ifi_oerrors,
                                        if2m->ifm_data.ifi_iqdrops,
                                        0);  // dropout not supported
            if (!py_ifc_info)
                goto error;
            if (PyDict_SetItemString(py_retdict, ifc_name, py_ifc_info))
                goto error;
            Py_DECREF(py_ifc_info);
        }
        else {
            continue;
        }
    }

    free(buf);
    return py_retdict;

error:
    Py_XDECREF(py_ifc_info);
    Py_DECREF(py_retdict);
    if (buf != NULL)
        free(buf);
    return NULL;
}


/*
 * Return a Python dict of tuples for disk I/O information
 */
static PyObject *
psutil_disk_io_counters(PyObject *self, PyObject *args)
{
    int i;
    struct statinfo stats;

    PyObject *py_retdict = PyDict_New();
    PyObject *py_disk_info = NULL;

    if (py_retdict == NULL)
        return NULL;
    if (devstat_checkversion(NULL) < 0) {
        PyErr_Format(PyExc_RuntimeError, "devstat_checkversion() failed");
        goto error;
    }

    stats.dinfo = (struct devinfo *)malloc(sizeof(struct devinfo));
    if (stats.dinfo == NULL) {
        PyErr_NoMemory();
        goto error;
    }
    bzero(stats.dinfo, sizeof(struct devinfo));

    if (devstat_getdevs(NULL, &stats) == -1) {
        PyErr_Format(PyExc_RuntimeError, "devstat_getdevs() failed");
        goto error;
    }

    for (i = 0; i < stats.dinfo->numdevs; i++) {
        py_disk_info = NULL;
        struct devstat current;
        char disk_name[128];
        current = stats.dinfo->devices[i];
        snprintf(disk_name, sizeof(disk_name), "%s%d",
                 current.device_name,
                 current.unit_number);

        py_disk_info = Py_BuildValue(
            "(KKKKLL)",
            current.operations[DEVSTAT_READ],   // no reads
            current.operations[DEVSTAT_WRITE],  // no writes
            current.bytes[DEVSTAT_READ],        // bytes read
            current.bytes[DEVSTAT_WRITE],       // bytes written
            (long long)devstat_compute_etime(
                &current.duration[DEVSTAT_READ], NULL),  // r time
            (long long)devstat_compute_etime(
                &current.duration[DEVSTAT_WRITE], NULL));  // w time
        if (!py_disk_info)
            goto error;
        if (PyDict_SetItemString(py_retdict, disk_name, py_disk_info))
            goto error;
        Py_DECREF(py_disk_info);
    }

    if (stats.dinfo->mem_ptr)
        free(stats.dinfo->mem_ptr);
    free(stats.dinfo);
    return py_retdict;

error:
    Py_XDECREF(py_disk_info);
    Py_DECREF(py_retdict);
    if (stats.dinfo != NULL)
        free(stats.dinfo);
    return NULL;
}


/*
 * Return currently connected users as a list of tuples.
 */
static PyObject *
psutil_users(PyObject *self, PyObject *args)
{
    PyObject *ret_list = PyList_New(0);
    PyObject *tuple = NULL;

    if (ret_list == NULL)
        return NULL;

#if __FreeBSD_version < 900000
    struct utmp ut;
    FILE *fp;

    fp = fopen(_PATH_UTMP, "r");
    if (fp == NULL) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    while (fread(&ut, sizeof(ut), 1, fp) == 1) {
        if (*ut.ut_name == '\0')
            continue;
        tuple = Py_BuildValue(
            "(sssf)",
            ut.ut_name,         // username
            ut.ut_line,         // tty
            ut.ut_host,         // hostname
           (float)ut.ut_time);  // start time
        if (!tuple) {
            fclose(fp);
            goto error;
        }
        if (PyList_Append(ret_list, tuple)) {
            fclose(fp);
            goto error;
        }
        Py_DECREF(tuple);
    }

    fclose(fp);
#else
    struct utmpx *utx;

    while ((utx = getutxent()) != NULL) {
        if (utx->ut_type != USER_PROCESS)
            continue;
        tuple = Py_BuildValue(
            "(sssf)",
            utx->ut_user,  // username
            utx->ut_line,  // tty
            utx->ut_host,  // hostname
            (float)utx->ut_tv.tv_sec  // start time
        );

        if (!tuple) {
            endutxent();
            goto error;
        }
        if (PyList_Append(ret_list, tuple)) {
            endutxent();
            goto error;
        }
        Py_DECREF(tuple);
    }

    endutxent();
#endif
    return ret_list;

error:
    Py_XDECREF(tuple);
    Py_DECREF(ret_list);
    return NULL;
}



/*
 * System-wide open connections.
 */

#define HASHSIZE 1009
static struct xfile *psutil_xfiles;
static int psutil_nxfiles;

int
psutil_populate_xfiles()
{
    size_t len;

    if ((psutil_xfiles = malloc(len = sizeof *psutil_xfiles)) == NULL) {
        PyErr_NoMemory();
        return 0;
    }
    while (sysctlbyname("kern.file", psutil_xfiles, &len, 0, 0) == -1) {
        if (errno != ENOMEM) {
            PyErr_SetFromErrno(0);
            return 0;
        }
        len *= 2;
        if ((psutil_xfiles = realloc(psutil_xfiles, len)) == NULL) {
            PyErr_NoMemory();
            return 0;
        }
    }
    if (len > 0 && psutil_xfiles->xf_size != sizeof *psutil_xfiles) {
        PyErr_Format(PyExc_RuntimeError, "struct xfile size mismatch");
        return 0;
    }
    psutil_nxfiles = len / sizeof *psutil_xfiles;
    return 1;
}

int
psutil_get_pid_from_sock(int sock_hash)
{
    struct xfile *xf;
    int hash, n;
    for (xf = psutil_xfiles, n = 0; n < psutil_nxfiles; ++n, ++xf) {
        if (xf->xf_data == NULL)
            continue;
        hash = (int)((uintptr_t)xf->xf_data % HASHSIZE);
        if (sock_hash == hash)
            return xf->xf_pid;
    }
    return -1;
}


// Reference:
// https://gitorious.org/freebsd/freebsd/source/
//     f1d6f4778d2044502209708bc167c05f9aa48615:usr.bin/sockstat/sockstat.c
int psutil_gather_inet(int proto, PyObject *py_retlist)
{
    struct xinpgen *xig, *exig;
    struct xinpcb *xip;
    struct xtcpcb *xtp;
    struct inpcb *inp;
    struct xsocket *so;
    const char *varname = NULL;
    size_t len, bufsize;
    void *buf;
    int hash;
    int retry;
    int type;

    PyObject *tuple = NULL;
    PyObject *laddr = NULL;
    PyObject *raddr = NULL;

    switch (proto) {
        case IPPROTO_TCP:
            varname = "net.inet.tcp.pcblist";
            type = SOCK_STREAM;
            break;
        case IPPROTO_UDP:
            varname = "net.inet.udp.pcblist";
            type = SOCK_DGRAM;
            break;
    }

    buf = NULL;
    bufsize = 8192;
    retry = 5;
    do {
        for (;;) {
            buf = realloc(buf, bufsize);
            if (buf == NULL)
                continue;  // XXX
            len = bufsize;
            if (sysctlbyname(varname, buf, &len, NULL, 0) == 0)
                break;
            if (errno != ENOMEM) {
                PyErr_SetFromErrno(0);
                goto error;
            }
            bufsize *= 2;
        }
        xig = (struct xinpgen *)buf;
        exig = (struct xinpgen *)(void *)((char *)buf + len - sizeof *exig);
        if (xig->xig_len != sizeof *xig || exig->xig_len != sizeof *exig) {
            PyErr_Format(PyExc_RuntimeError, "struct xinpgen size mismatch");
            goto error;
        }
    } while (xig->xig_gen != exig->xig_gen && retry--);


    for (;;) {
        int lport, rport, pid, status, family;

        xig = (struct xinpgen *)(void *)((char *)xig + xig->xig_len);
        if (xig >= exig)
            break;

        switch (proto) {
            case IPPROTO_TCP:
                xtp = (struct xtcpcb *)xig;
                if (xtp->xt_len != sizeof *xtp) {
                    PyErr_Format(PyExc_RuntimeError,
                                 "struct xtcpcb size mismatch");
                    goto error;
                }
                inp = &xtp->xt_inp;
                so = &xtp->xt_socket;
                status = xtp->xt_tp.t_state;
                break;
            case IPPROTO_UDP:
                xip = (struct xinpcb *)xig;
                if (xip->xi_len != sizeof *xip) {
                    PyErr_Format(PyExc_RuntimeError,
                                 "struct xinpcb size mismatch");
                    goto error;
                }
                inp = &xip->xi_inp;
                so = &xip->xi_socket;
                status = PSUTIL_CONN_NONE;
                break;
            default:
                PyErr_Format(PyExc_RuntimeError, "invalid proto");
                goto error;
        }

        char lip[200], rip[200];

        hash = (int)((uintptr_t)so->xso_so % HASHSIZE);
        pid = psutil_get_pid_from_sock(hash);
        if (pid < 0)
            continue;
        lport = ntohs(inp->inp_lport);
        rport = ntohs(inp->inp_fport);

        if (inp->inp_vflag & INP_IPV4) {
            family = AF_INET;
            inet_ntop(AF_INET, &inp->inp_laddr.s_addr, lip, sizeof(lip));
            inet_ntop(AF_INET, &inp->inp_faddr.s_addr, rip, sizeof(rip));
        }
        else if (inp->inp_vflag & INP_IPV6) {
            family = AF_INET6;
            inet_ntop(AF_INET6, &inp->in6p_laddr.s6_addr, lip, sizeof(lip));
            inet_ntop(AF_INET6, &inp->in6p_faddr.s6_addr, rip, sizeof(rip));
        }

        // construct python tuple/list
        laddr = Py_BuildValue("(si)", lip, lport);
        if (!laddr)
            goto error;
        if (rport != 0)
            raddr = Py_BuildValue("(si)", rip, rport);
        else
            raddr = Py_BuildValue("()");
        if (!raddr)
            goto error;
        tuple = Py_BuildValue("(iiiNNii)", -1, family, type, laddr, raddr,
                                               status, pid);
        if (!tuple)
            goto error;
        if (PyList_Append(py_retlist, tuple))
            goto error;
        Py_DECREF(tuple);
    }

    free(buf);
    return 1;

error:
    Py_XDECREF(tuple);
    Py_XDECREF(laddr);
    Py_XDECREF(raddr);
    free(buf);
    return 0;
}


int psutil_gather_unix(int proto, PyObject *py_retlist)
{
    struct xunpgen *xug, *exug;
    struct xunpcb *xup;
    const char *varname = NULL;
    const char *protoname = NULL;
    size_t len;
    size_t bufsize;
    void *buf;
    int hash;
    int retry;
    int pid;
    struct sockaddr_un *sun;
    char path[PATH_MAX];

    PyObject *tuple = NULL;
    PyObject *laddr = NULL;
    PyObject *raddr = NULL;

    switch (proto) {
        case SOCK_STREAM:
            varname = "net.local.stream.pcblist";
            protoname = "stream";
            break;
        case SOCK_DGRAM:
            varname = "net.local.dgram.pcblist";
            protoname = "dgram";
            break;
    }

    buf = NULL;
    bufsize = 8192;
    retry = 5;

    do {
        for (;;) {
            buf = realloc(buf, bufsize);
            if (buf == NULL) {
                PyErr_NoMemory();
                goto error;
            }
            len = bufsize;
            if (sysctlbyname(varname, buf, &len, NULL, 0) == 0)
                break;
            if (errno != ENOMEM) {
                PyErr_SetFromErrno(0);
                goto error;
            }
            bufsize *= 2;
        }
        xug = (struct xunpgen *)buf;
        exug = (struct xunpgen *)(void *)
            ((char *)buf + len - sizeof *exug);
        if (xug->xug_len != sizeof *xug || exug->xug_len != sizeof *exug) {
            PyErr_Format(PyExc_RuntimeError, "struct xinpgen size mismatch");
            goto error;
        }
    } while (xug->xug_gen != exug->xug_gen && retry--);

    for (;;) {
        xug = (struct xunpgen *)(void *)((char *)xug + xug->xug_len);
        if (xug >= exug)
            break;
        xup = (struct xunpcb *)xug;
        if (xup->xu_len != sizeof *xup)
            goto error;

        hash = (int)((uintptr_t) xup->xu_socket.xso_so % HASHSIZE);
        pid = psutil_get_pid_from_sock(hash);
        if (pid < 0)
            continue;

        sun = (struct sockaddr_un *)&xup->xu_addr;
        snprintf(path, sizeof(path), "%.*s",
                 (int)(sun->sun_len - (sizeof(*sun) - sizeof(sun->sun_path))),
                 sun->sun_path);

        tuple = Py_BuildValue("(iiisOii)", -1, AF_UNIX, proto, path, Py_None,
                                               PSUTIL_CONN_NONE, pid);
        if (!tuple)
            goto error;
        if (PyList_Append(py_retlist, tuple))
            goto error;
        Py_DECREF(tuple);
        Py_INCREF(Py_None);
    }

    free(buf);
    return 1;

error:
    Py_XDECREF(tuple);
    Py_XDECREF(laddr);
    Py_XDECREF(raddr);
    free(buf);
    return 0;
}


/*
 * Return system-wide open connections.
 */
static PyObject*
psutil_net_connections(PyObject* self, PyObject* args)
{
    PyObject *py_retlist = PyList_New(0);

    if (py_retlist == NULL)
        return NULL;
    if (psutil_populate_xfiles() != 1)
        goto error;
    if (psutil_gather_inet(IPPROTO_TCP, py_retlist) == 0)
        goto error;
    if (psutil_gather_inet(IPPROTO_UDP, py_retlist) == 0)
        goto error;
    if (psutil_gather_unix(SOCK_STREAM, py_retlist) == 0)
       goto error;
    if (psutil_gather_unix(SOCK_DGRAM, py_retlist) == 0)
        goto error;

    free(psutil_xfiles);
    return py_retlist;

error:
    Py_DECREF(py_retlist);
    free(psutil_xfiles);
    return NULL;
}


/*
 * Get process CPU affinity.
 * Reference: http://sources.freebsd.org/RELENG_9/src/usr.bin/cpuset/cpuset.c
 */
static PyObject*
psutil_proc_cpu_affinity_get(PyObject* self, PyObject* args)
{
    long pid;
    int ret;
    int i;
    cpuset_t mask;
    PyObject* py_retlist;
    PyObject* py_cpu_num;

    if (!PyArg_ParseTuple(args, "i", &pid))
        return NULL;
    ret = cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid,
                             sizeof(mask), &mask);
    if (ret != 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }

    py_retlist = PyList_New(0);
    if (py_retlist == NULL)
        return NULL;

    for (i = 0; i < CPU_SETSIZE; i++) {
        if (CPU_ISSET(i, &mask)) {
            py_cpu_num = Py_BuildValue("i", i);
            if (py_cpu_num == NULL)
                goto error;
            if (PyList_Append(py_retlist, py_cpu_num))
                goto error;
        }
    }

    return py_retlist;

error:
    Py_XDECREF(py_cpu_num);
    Py_DECREF(py_retlist);
    return NULL;
}


/*
 * Set process CPU affinity.
 * Reference: http://sources.freebsd.org/RELENG_9/src/usr.bin/cpuset/cpuset.c
 */
static PyObject *
psutil_proc_cpu_affinity_set(PyObject *self, PyObject *args)
{
    long pid;
    int i;
    int seq_len;
    int ret;
    cpuset_t cpu_set;
    PyObject *py_cpu_set;
    PyObject *py_cpu_seq = NULL;

    if (!PyArg_ParseTuple(args, "lO", &pid, &py_cpu_set))
        return NULL;

    py_cpu_seq = PySequence_Fast(py_cpu_set, "expected a sequence or integer");
    if (!py_cpu_seq)
        return NULL;
    seq_len = PySequence_Fast_GET_SIZE(py_cpu_seq);

    // calculate the mask
    CPU_ZERO(&cpu_set);
    for (i = 0; i < seq_len; i++) {
        PyObject *item = PySequence_Fast_GET_ITEM(py_cpu_seq, i);
#if PY_MAJOR_VERSION >= 3
        long value = PyLong_AsLong(item);
#else
        long value = PyInt_AsLong(item);
#endif
        if (value == -1 && PyErr_Occurred())
            goto error;
        CPU_SET(value, &cpu_set);
    }

    // set affinity
    ret = cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, pid,
                             sizeof(cpu_set), &cpu_set);
    if (ret != 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        goto error;
    }

    Py_DECREF(py_cpu_seq);
    Py_RETURN_NONE;

error:
    if (py_cpu_seq != NULL)
        Py_DECREF(py_cpu_seq);
    return NULL;
}


/*
 * define the psutil C module methods and initialize the module.
 */
static PyMethodDef
PsutilMethods[] =
{
    // --- per-process functions

    {"proc_name", psutil_proc_name, METH_VARARGS,
     "Return process name"},
    {"proc_connections", psutil_proc_connections, METH_VARARGS,
     "Return connections opened by process"},
    {"proc_exe", psutil_proc_exe, METH_VARARGS,
     "Return process pathname executable"},
    {"proc_cmdline", psutil_proc_cmdline, METH_VARARGS,
     "Return process cmdline as a list of cmdline arguments"},
    {"proc_ppid", psutil_proc_ppid, METH_VARARGS,
     "Return process ppid as an integer"},
    {"proc_uids", psutil_proc_uids, METH_VARARGS,
     "Return process real effective and saved user ids as a Python tuple"},
    {"proc_gids", psutil_proc_gids, METH_VARARGS,
     "Return process real effective and saved group ids as a Python tuple"},
    {"proc_cpu_times", psutil_proc_cpu_times, METH_VARARGS,
     "Return tuple of user/kern time for the given PID"},
    {"proc_create_time", psutil_proc_create_time, METH_VARARGS,
     "Return a float indicating the process create time expressed in "
     "seconds since the epoch"},
    {"proc_memory_info", psutil_proc_memory_info, METH_VARARGS,
     "Return extended memory info for a process as a Python tuple."},
    {"proc_num_threads", psutil_proc_num_threads, METH_VARARGS,
     "Return number of threads used by process"},
    {"proc_num_ctx_switches", psutil_proc_num_ctx_switches, METH_VARARGS,
     "Return the number of context switches performed by process"},
    {"proc_threads", psutil_proc_threads, METH_VARARGS,
     "Return process threads"},
    {"proc_status", psutil_proc_status, METH_VARARGS,
     "Return process status as an integer"},
    {"proc_io_counters", psutil_proc_io_counters, METH_VARARGS,
     "Return process IO counters"},
    {"proc_tty_nr", psutil_proc_tty_nr, METH_VARARGS,
     "Return process tty (terminal) number"},
    {"proc_cpu_affinity_get", psutil_proc_cpu_affinity_get, METH_VARARGS,
     "Return process CPU affinity."},
    {"proc_cpu_affinity_set", psutil_proc_cpu_affinity_set, METH_VARARGS,
     "Set process CPU affinity."},
#if defined(__FreeBSD_version) && __FreeBSD_version >= 800000
    {"proc_open_files", psutil_proc_open_files, METH_VARARGS,
     "Return files opened by process as a list of (path, fd) tuples"},
    {"proc_cwd", psutil_proc_cwd, METH_VARARGS,
     "Return process current working directory."},
    {"proc_memory_maps", psutil_proc_memory_maps, METH_VARARGS,
     "Return a list of tuples for every process's memory map"},
    {"proc_num_fds", psutil_proc_num_fds, METH_VARARGS,
     "Return the number of file descriptors opened by this process"},
#endif

    // --- system-related functions

    {"pids", psutil_pids, METH_VARARGS,
     "Returns a list of PIDs currently running on the system"},
    {"cpu_count_logical", psutil_cpu_count_logical, METH_VARARGS,
     "Return number of logical CPUs on the system"},
    {"cpu_count_phys", psutil_cpu_count_phys, METH_VARARGS,
     "Return an XML string to determine the number physical CPUs."},
    {"virtual_mem", psutil_virtual_mem, METH_VARARGS,
     "Return system virtual memory usage statistics"},
    {"swap_mem", psutil_swap_mem, METH_VARARGS,
     "Return swap mem stats"},
    {"cpu_times", psutil_cpu_times, METH_VARARGS,
     "Return system cpu times as a tuple (user, system, nice, idle, irc)"},
#if defined(__FreeBSD_version) && __FreeBSD_version >= 800000
    {"per_cpu_times", psutil_per_cpu_times, METH_VARARGS,
     "Return system per-cpu times as a list of tuples"},
#endif
    {"boot_time", psutil_boot_time, METH_VARARGS,
     "Return the system boot time expressed in seconds since the epoch."},
    {"disk_partitions", psutil_disk_partitions, METH_VARARGS,
     "Return a list of tuples including device, mount point and "
     "fs type for all partitions mounted on the system."},
    {"net_io_counters", psutil_net_io_counters, METH_VARARGS,
     "Return dict of tuples of networks I/O information."},
    {"disk_io_counters", psutil_disk_io_counters, METH_VARARGS,
     "Return a Python dict of tuples for disk I/O information"},
    {"users", psutil_users, METH_VARARGS,
     "Return currently connected users as a list of tuples"},
    {"net_connections", psutil_net_connections, METH_VARARGS,
     "Return system-wide open connections."},

    {NULL, NULL, 0, NULL}
};

struct module_state {
    PyObject *error;
};

#if PY_MAJOR_VERSION >= 3
#define GETSTATE(m) ((struct module_state*)PyModule_GetState(m))
#else
#define GETSTATE(m) (&_state)
#endif

#if PY_MAJOR_VERSION >= 3

static int
psutil_bsd_traverse(PyObject *m, visitproc visit, void *arg) {
    Py_VISIT(GETSTATE(m)->error);
    return 0;
}

static int
psutil_bsd_clear(PyObject *m) {
    Py_CLEAR(GETSTATE(m)->error);
    return 0;
}

static struct PyModuleDef
        moduledef = {
    PyModuleDef_HEAD_INIT,
    "psutil_bsd",
    NULL,
    sizeof(struct module_state),
    PsutilMethods,
    NULL,
    psutil_bsd_traverse,
    psutil_bsd_clear,
    NULL
};

#define INITERROR return NULL

PyMODINIT_FUNC PyInit__psutil_bsd(void)

#else
#define INITERROR return

void init_psutil_bsd(void)
#endif
{
#if PY_MAJOR_VERSION >= 3
    PyObject *module = PyModule_Create(&moduledef);
#else
    PyObject *module = Py_InitModule("_psutil_bsd", PsutilMethods);
#endif
    PyModule_AddIntConstant(module, "version", PSUTIL_VERSION);

    // process status constants
    PyModule_AddIntConstant(module, "SSTOP", SSTOP);
    PyModule_AddIntConstant(module, "SSLEEP", SSLEEP);
    PyModule_AddIntConstant(module, "SRUN", SRUN);
    PyModule_AddIntConstant(module, "SIDL", SIDL);
    PyModule_AddIntConstant(module, "SWAIT", SWAIT);
    PyModule_AddIntConstant(module, "SLOCK", SLOCK);
    PyModule_AddIntConstant(module, "SZOMB", SZOMB);
    // connection status constants
    PyModule_AddIntConstant(module, "TCPS_CLOSED", TCPS_CLOSED);
    PyModule_AddIntConstant(module, "TCPS_CLOSING", TCPS_CLOSING);
    PyModule_AddIntConstant(module, "TCPS_CLOSE_WAIT", TCPS_CLOSE_WAIT);
    PyModule_AddIntConstant(module, "TCPS_LISTEN", TCPS_LISTEN);
    PyModule_AddIntConstant(module, "TCPS_ESTABLISHED", TCPS_ESTABLISHED);
    PyModule_AddIntConstant(module, "TCPS_SYN_SENT", TCPS_SYN_SENT);
    PyModule_AddIntConstant(module, "TCPS_SYN_RECEIVED", TCPS_SYN_RECEIVED);
    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_1", TCPS_FIN_WAIT_1);
    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_2", TCPS_FIN_WAIT_2);
    PyModule_AddIntConstant(module, "TCPS_LAST_ACK", TCPS_LAST_ACK);
    PyModule_AddIntConstant(module, "TCPS_TIME_WAIT", TCPS_TIME_WAIT);
    PyModule_AddIntConstant(module, "PSUTIL_CONN_NONE", PSUTIL_CONN_NONE);

    if (module == NULL)
        INITERROR;
#if PY_MAJOR_VERSION >= 3
    return module;
#endif
}
