/*
 * Copyright (c) 2003, Trent Nelson, <trent@arpa.com>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTIFSTAT_ERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: src/usr.bin/systat/ifstat.c,v 1.7 2008/01/12 00:11:26 delphij Exp $
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_mib.h>

#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
#include <errno.h>

#include "systat.h"
#include "extern.h"
#include "convtbl.h"

                                /* Column numbers */

#define C1      0               /*  0-19 */
#define C2      20              /* 20-39 */
#define C3      40              /* 40-59 */
#define C4      60              /* 60-80 */
#define C5      80              /* Used for label positioning. */

#if 0
static const int col0 = 0;
static const int col1 = C1;
#endif
static const int col2 = C2;
static const int col3 = C3;
static const int col4 = C4;
#if 0
static const int col5 = C5;
#endif


static SLIST_HEAD(, if_stat) curlist;

struct if_stat {
        SLIST_ENTRY(if_stat)     link;
        char    if_name[IF_NAMESIZE];
        struct  ifmibdata if_mib;
        struct  timeval tv;
        struct  timeval tv_lastchanged;
        u_long  if_in_curtraffic;
        u_long  if_out_curtraffic;
        u_long  if_in_traffic_peak;
        u_long  if_out_traffic_peak;
        u_int   if_row;                 /* Index into ifmib sysctl */
        u_int   if_ypos;                /* 0 if not being displayed */
        u_int   display;
};

extern   u_int curscale;

static   void  right_align_string(struct if_stat *);
static   void  getifmibdata(const int, struct ifmibdata *);
static   void  sort_interface_list(void);
static   u_int getifnum(void);

#define IFSTAT_ERR(n, s)        do {                                    \
        putchar('');                                                   \
        closeifstat(wnd);                                               \
        err((n), (s));                                                  \
} while (0)

#define STARTING_ROW    (8)
#define ROW_SPACING     (3)

#define TOPLINE 5
#define TOPLABEL \
"      Interface           Traffic               Peak                Total"

#define CLEAR_LINE(y, x)        do {                                    \
        wmove(wnd, y, x);                                               \
        wclrtoeol(wnd);                                                 \
} while (0)

#define IN_col2         (ifp->if_in_curtraffic)
#define OUT_col2        (ifp->if_out_curtraffic)
#define IN_col3         (ifp->if_in_traffic_peak)
#define OUT_col3        (ifp->if_out_traffic_peak)
#define IN_col4         (ifp->if_mib.ifmd_data.ifi_ibytes)
#define OUT_col4        (ifp->if_mib.ifmd_data.ifi_obytes)

#define EMPTY_COLUMN    "                    "
#define CLEAR_COLUMN(y, x)      mvprintw((y), (x), "%20s", EMPTY_COLUMN);

#define DOPUTRATE(c, r, d)      do {                                    \
        CLEAR_COLUMN(r, c);                                             \
        mvprintw(r, (c), "%10.3f %s%s  ",                               \
                 convert(d##_##c, curscale),                            \
                 get_string(d##_##c, curscale),                         \
                 "/s");                                                 \
} while (0)

#define DOPUTTOTAL(c, r, d)     do {                                    \
        CLEAR_COLUMN((r), (c));                                         \
        mvprintw((r), (c), "%12.3f %s  ",                               \
                 convert(d##_##c, SC_AUTOBYTE),                         \
                 get_string(d##_##c, SC_AUTOBYTE));                     \
} while (0)

#define PUTRATE(c, r)   do {                                            \
        DOPUTRATE(c, (r), IN);                                          \
        DOPUTRATE(c, (r)+1, OUT);                                       \
} while (0)

#define PUTTOTAL(c, r)  do {                                            \
        DOPUTTOTAL(c, (r), IN);                                         \
        DOPUTTOTAL(c, (r)+1, OUT);                                      \
} while (0)

#define PUTNAME(p) do {                                                 \
        mvprintw(p->if_ypos, 0, "%s", p->if_name);                      \
        mvprintw(p->if_ypos, col2-3, "%s", (const char *)"in");         \
        mvprintw(p->if_ypos+1, col2-3, "%s", (const char *)"out");      \
} while (0)


WINDOW *
openifstat(void)
{
        struct   if_stat *p = NULL;
        u_int    n = 0, i = 0;

        n = getifnum();         /* NOTE: can return < 0 */

        SLIST_INIT(&curlist);
        for (i = 0; i < n; i++) {
                p = (struct if_stat *)calloc(1, sizeof(struct if_stat));
                if (p == NULL)
                        IFSTAT_ERR(1, "out of memory");
                SLIST_INSERT_HEAD(&curlist, p, link);
                p->if_row = i+1;
                getifmibdata(p->if_row, &p->if_mib);
                right_align_string(p);

                /*
                 * Initially, we only display interfaces that have
                 * received some traffic.
                 */
                if (p->if_mib.ifmd_data.ifi_ibytes != 0)
                        p->display = 1;
        }

        sort_interface_list();

        return (subwin(stdscr, LINES-1-5, 0, 5, 0));
}

void
closeifstat(WINDOW *w)
{
        struct if_stat  *node = NULL;

        while (!SLIST_EMPTY(&curlist)) {
                node = SLIST_FIRST(&curlist);
                SLIST_REMOVE_HEAD(&curlist, link);
                free(node);
        }

        if (w != NULL) {
                wclear(w);
                wrefresh(w);
                delwin(w);
        }

        return;
}


void
labelifstat(void)
{

        wmove(wnd, TOPLINE, 0);
        wclrtoeol(wnd);
        mvprintw(TOPLINE, 0, "%s", TOPLABEL);

        return;
}

void
showifstat(void)
{
        struct  if_stat *ifp = NULL;
        SLIST_FOREACH(ifp, &curlist, link) {
                if (ifp->display == 0)
                        continue;
                PUTNAME(ifp);
                PUTRATE(col2, ifp->if_ypos);
                PUTRATE(col3, ifp->if_ypos);
                PUTTOTAL(col4, ifp->if_ypos);
        }

        return;
}

int
initifstat(void)
{
        return 1;
}

void
fetchifstat(void)
{
        struct  if_stat *ifp = NULL;
        struct  timeval tv, new_tv, old_tv;
        double  elapsed = 0.0;
        u_int   new_inb, new_outb, old_inb, old_outb = 0;
        u_int   we_need_to_sort_interface_list = 0;

        SLIST_FOREACH(ifp, &curlist, link) {
                /*
                 * Grab a copy of the old input/output values before we
                 * call getifmibdata().
                 */
                old_inb = ifp->if_mib.ifmd_data.ifi_ibytes;
                old_outb = ifp->if_mib.ifmd_data.ifi_obytes;
                ifp->tv_lastchanged = ifp->if_mib.ifmd_data.ifi_lastchange;

                if (gettimeofday(&new_tv, NULL) != 0)
                        IFSTAT_ERR(2, "error getting time of day");
                (void)getifmibdata(ifp->if_row, &ifp->if_mib);


                new_inb = ifp->if_mib.ifmd_data.ifi_ibytes;
                new_outb = ifp->if_mib.ifmd_data.ifi_obytes;

                /* Display interface if it's received some traffic. */
                if (new_inb > 0 && old_inb == 0) {
                        ifp->display = 1;
                        we_need_to_sort_interface_list++;
                }

                /*
                 * The rest is pretty trivial.  Calculate the new values
                 * for our current traffic rates, and while we're there,
                 * see if we have new peak rates.
                 */
                old_tv = ifp->tv;
                timersub(&new_tv, &old_tv, &tv);
                elapsed = tv.tv_sec + (tv.tv_usec * 1e-6);

                ifp->if_in_curtraffic = new_inb - old_inb;
                ifp->if_out_curtraffic = new_outb - old_outb;

                /*
                 * Rather than divide by the time specified on the comm-
                 * and line, we divide by ``elapsed'' as this is likely
                 * to be more accurate.
                 */
                ifp->if_in_curtraffic /= elapsed;
                ifp->if_out_curtraffic /= elapsed;

                if (ifp->if_in_curtraffic > ifp->if_in_traffic_peak)
                        ifp->if_in_traffic_peak = ifp->if_in_curtraffic;

                if (ifp->if_out_curtraffic > ifp->if_out_traffic_peak)
                        ifp->if_out_traffic_peak = ifp->if_out_curtraffic;

                ifp->tv.tv_sec = new_tv.tv_sec;
                ifp->tv.tv_usec = new_tv.tv_usec;

        }

        if (we_need_to_sort_interface_list)
                sort_interface_list();

        return;
}

/*
 * We want to right justify our interface names against the first column
 * (first sixteen or so characters), so we need to do some alignment.
 */
static void
right_align_string(struct if_stat *ifp)
{
        int      str_len = 0, pad_len = 0;
        char    *newstr = NULL, *ptr = NULL;

        if (ifp == NULL || ifp->if_mib.ifmd_name[0] == '\0')
                return;
        else {
                /* string length + '\0' */
                str_len = strlen(ifp->if_mib.ifmd_name)+1;
                pad_len = IF_NAMESIZE-(str_len);

                newstr = ifp->if_name;
                ptr = newstr + pad_len;
                (void)memset((void *)newstr, (int)' ', IF_NAMESIZE);
                (void)strncpy(ptr, (const char *)&ifp->if_mib.ifmd_name,
                              str_len);
        }

        return;
}

/*
 * This function iterates through our list of interfaces, identifying
 * those that are to be displayed (ifp->display = 1).  For each interf-
 * rface that we're displaying, we generate an appropriate position for
 * it on the screen (ifp->if_ypos).
 *
 * This function is called any time a change is made to an interface's
 * ``display'' state.
 */
void
sort_interface_list(void)
{
        struct  if_stat *ifp = NULL;
        u_int   y = 0;

        y = STARTING_ROW;
        SLIST_FOREACH(ifp, &curlist, link) {
                if (ifp->display) {
                        ifp->if_ypos = y;
                        y += ROW_SPACING;
                }
        }
}

static
unsigned int
getifnum(void)
{
        u_int   data    = 0;
        size_t  datalen = 0;
        static  int name[] = { CTL_NET,
                               PF_LINK,
                               NETLINK_GENERIC,
                               IFMIB_SYSTEM,
                               IFMIB_IFCOUNT };

        datalen = sizeof(data);
        if (sysctl(name, 5, (void *)&data, (size_t *)&datalen, NULL,
            (size_t)0) != 0)
                IFSTAT_ERR(1, "sysctl error");
        return data;
}

static void
getifmibdata(int row, struct ifmibdata *data)
{
        size_t  datalen = 0;
        static  int name[] = { CTL_NET,
                               PF_LINK,
                               NETLINK_GENERIC,
                               IFMIB_IFDATA,
                               0,
                               IFDATA_GENERAL };
        datalen = sizeof(*data);
        name[4] = row;

        if ((sysctl(name, 6, (void *)data, (size_t *)&datalen, NULL,
            (size_t)0) != 0) && (errno != ENOENT))
                IFSTAT_ERR(2, "sysctl error getting interface data");
}

int
cmdifstat(const char *cmd, char *args)
{
        int     retval = 0;

        retval = ifcmd(cmd, args);
        /* ifcmd() returns 1 on success */
        if (retval == 1) {
                showifstat();
                refresh();
        }

        return retval;
}