Code

Merge branches 'mark' and 'timeout'
[liboping.git] / src / oping.c
index 3d1edddccb4819479d125387b8a5da3c40428622..6263a4def36459c7d94c8dbbb362cc89b56a9f6e 100644 (file)
@@ -1,6 +1,6 @@
 /**
  * Object oriented C module to send ICMP and ICMPv6 `echo's.
- * Copyright (C) 2006  Florian octo Forster <octo at verplant.org>
+ * Copyright (C) 2006-2014  Florian octo Forster <ff at octo.it>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
 # include <stdlib.h>
 # include <stdio.h>
 # include <string.h>
+# include <stdint.h>
+# include <inttypes.h>
 # include <errno.h>
 # include <assert.h>
-# include <unistd.h>
 #else
 # error "You don't have the standard C99 header files installed"
 #endif /* STDC_HEADERS */
 
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
 #if HAVE_MATH_H
 # include <math.h>
 #endif
 # endif
 #endif
 
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+#if HAVE_NETINET_IN_H
+# include <netinet/in.h>
+#endif
+#if HAVE_NETINET_IP_H
+# include <netinet/ip.h>
+#endif
+
 #if HAVE_NETDB_H
 # include <netdb.h> /* NI_MAXHOST */
 #endif
 # include <signal.h>
 #endif
 
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include <locale.h>
+#include <langinfo.h>
+
+#if USE_NCURSES
+# define NCURSES_OPAQUE 1
+/* http://newsgroups.derkeiler.com/Archive/Rec/rec.games.roguelike.development/2010-09/msg00050.html */
+# define _X_OPEN_SOURCE_EXTENDED
+
+# if HAVE_NCURSESW_NCURSES_H
+#  include <ncursesw/ncurses.h>
+# elif HAVE_NCURSES_H
+#  include <ncurses.h>
+# endif
+
+# define OPING_GREEN 1
+# define OPING_YELLOW 2
+# define OPING_RED 3
+# define OPING_GREEN_HIST 4
+# define OPING_YELLOW_HIST 5
+# define OPING_RED_HIST 6
+
+double const threshold_green = 0.8;
+double const threshold_yellow = 0.95;
+
+static char const * const hist_symbols_utf8[] = {
+       "▁", "▂", "▃", "▄", "▅", "▆", "▇", "█" };
+static size_t const hist_symbols_utf8_num = sizeof (hist_symbols_utf8)
+       / sizeof (hist_symbols_utf8[0]);
+
+/* scancodes for 6 levels of horizontal bars, ncurses-specific */
+/* those are not the usual constants because those are not constant */
+static int const hist_symbols_acs[] = {
+       115, /* ACS_S9 "⎽" */
+       114, /* ACS_S7 "⎼" */
+       113, /* ACS_S5 "─" */
+       112, /* ACS_S3 "⎻" */
+       111  /* ACS_S1 "⎺" */
+};
+static size_t const hist_symbols_acs_num = sizeof (hist_symbols_acs)
+       / sizeof (hist_symbols_acs[0]);
+
+/* use different colors without a background for scancodes */
+static int const hist_colors_utf8[] = {
+       OPING_GREEN_HIST, OPING_YELLOW_HIST, OPING_RED_HIST };
+static int const hist_colors_acs[] = {
+       OPING_GREEN, OPING_YELLOW, OPING_RED };
+/* assuming that both arrays are the same size */
+static size_t const hist_colors_num = sizeof (hist_colors_utf8)
+       / sizeof (hist_colors_utf8[0]);
+#endif
+
+/* "─" */
+#define BOXPLOT_WHISKER_BAR       (113 | A_ALTCHARSET)
+/* "├" */
+#define BOXPLOT_WHISKER_LEFT_END  (116 | A_ALTCHARSET)
+/* "┤" */
+#define BOXPLOT_WHISKER_RIGHT_END (117 | A_ALTCHARSET)
+/* Inverted */
+#define BOXPLOT_BOX               ' '
+/* "│", inverted */
+#define BOXPLOT_MEDIAN            (120 | A_ALTCHARSET)
+
 #include "oping.h"
 
+#ifndef _POSIX_SAVED_IDS
+# define _POSIX_SAVED_IDS 0
+#endif
+
+#ifndef IPTOS_MINCOST
+# define IPTOS_MINCOST 0x02
+#endif
+
+/* Remove GNU specific __attribute__ settings when using another compiler */
+#if !__GNUC__
+# define __attribute__(x) /**/
+#endif
+
 typedef struct ping_context
 {
        char host[NI_MAXHOST];
        char addr[NI_MAXHOST];
 
+       int index;
        int req_sent;
        int req_rcvd;
 
-       double latency_min;
-       double latency_max;
        double latency_total;
-       double latency_total_square;
+
+#ifndef HISTORY_SIZE_MAX
+# define HISTORY_SIZE_MAX 900
+#endif
+       /* The last n RTTs in the order they were sent. */
+       double history_by_time[HISTORY_SIZE_MAX];
+
+       /* Current number of entries in the history. This is a value between 0
+        * and HISTORY_SIZE_MAX. */
+       size_t history_size;
+
+       /* Number "received" entries in the history, i.e. non-NAN entries. */
+       size_t history_received;
+
+       /* Index of the next RTT to be written to history_by_time. This wraps
+        * around to 0 once the histroty has grown to HISTORY_SIZE_MAX. */
+       size_t history_index;
+
+       /* The last history_size RTTs sorted by value. timed out packets (NAN
+        * entries) are sorted to the back. */
+       double history_by_value[HISTORY_SIZE_MAX];
+
+       /* If set to true, history_by_value has to be re-calculated. */
+       _Bool history_dirty;
+
+#if USE_NCURSES
+       WINDOW *window;
+#endif
 } ping_context_t;
 
 static double  opt_interval   = 1.0;
+static double  opt_timeout    = PING_DEF_TIMEOUT;
 static int     opt_addrfamily = PING_DEF_AF;
 static char   *opt_srcaddr    = NULL;
 static char   *opt_device     = NULL;
+static char   *opt_mark       = NULL;
 static char   *opt_filename   = NULL;
 static int     opt_count      = -1;
 static int     opt_send_ttl   = 64;
+static uint8_t opt_send_qos   = 0;
+#define OPING_DEFAULT_PERCENTILE 95.0
+static double  opt_percentile = -1.0;
+static double  opt_exit_status_threshold = 1.0;
+#if USE_NCURSES
+static int     opt_show_graph = 1;
+static int     opt_utf8       = 0;
+#endif
+
+static int host_num = 0;
 
-static void sigint_handler (int signal)
+#if USE_NCURSES
+static WINDOW *main_win = NULL;
+#endif
+
+static void sigint_handler (int signal) /* {{{ */
 {
        /* Make compiler happy */
        signal = 0;
        /* Exit the loop */
        opt_count = 0;
-}
+} /* }}} void sigint_handler */
 
-static ping_context_t *context_create (void)
+static ping_context_t *context_create (void) /* {{{ */
 {
        ping_context_t *ret;
 
@@ -96,25 +232,199 @@ static ping_context_t *context_create (void)
 
        memset (ret, '\0', sizeof (ping_context_t));
 
-       ret->latency_min   = -1.0;
-       ret->latency_max   = -1.0;
        ret->latency_total = 0.0;
-       ret->latency_total_square = 0.0;
+
+#if USE_NCURSES
+       ret->window = NULL;
+#endif
 
        return (ret);
-}
+} /* }}} ping_context_t *context_create */
 
-static void context_destroy (ping_context_t *context)
+static void context_destroy (ping_context_t *context) /* {{{ */
 {
+       if (context == NULL)
+               return;
+
+#if USE_NCURSES
+       if (context->window != NULL)
+       {
+               delwin (context->window);
+               context->window = NULL;
+       }
+#endif
+
        free (context);
-}
+} /* }}} void context_destroy */
+
+static int compare_double (void const *arg0, void const *arg1) /* {{{ */
+{
+       double dbl0 = *((double *) arg0);
+       double dbl1 = *((double *) arg1);
+
+       if (isnan (dbl0))
+       {
+               if (isnan (dbl1))
+                       return 0;
+               else
+                       return 1;
+       }
+       else if (isnan (dbl1))
+               return -1;
+       else if (dbl0 < dbl1)
+               return -1;
+       else if (dbl0 > dbl1)
+               return 1;
+       else
+               return 0;
+} /* }}} int compare_double */
+
+static void clean_history (ping_context_t *ctx) /* {{{ */
+{
+       size_t i;
+
+       if (!ctx->history_dirty)
+               return;
+
+       /* Copy all values from by_time to by_value. */
+       memcpy (ctx->history_by_value, ctx->history_by_time,
+                       sizeof (ctx->history_by_time));
+
+       /* Sort all RTTs. */
+       qsort (ctx->history_by_value, ctx->history_size, sizeof
+                       (ctx->history_by_value[0]), compare_double);
+
+       /* Update the number of received RTTs. */
+       ctx->history_received = 0;
+       for (i = 0; i < ctx->history_size; i++)
+               if (!isnan (ctx->history_by_value[i]))
+                       ctx->history_received++;
+
+       /* Mark as clean. */
+       ctx->history_dirty = 0;
+} /* }}} void clean_history */
 
-static void usage_exit (const char *name, int status)
+static double percentile_to_latency (ping_context_t *ctx, /* {{{ */
+               double percentile)
 {
-       int name_length;
+       size_t index;
 
-       name_length = (int) strlen (name);
+       clean_history (ctx);
 
+       /* Not a single packet was received successfully. */
+       if (ctx->history_received == 0)
+               return NAN;
+
+       if (percentile <= 0.0)
+               index = 0;
+       else if (percentile >= 100.0)
+               index = ctx->history_received - 1;
+       else
+       {
+               index = (size_t) ceil ((percentile / 100.0) * ((double) ctx->history_received));
+               assert (index > 0);
+               index--;
+       }
+
+       return (ctx->history_by_value[index]);
+} /* }}} double percentile_to_latency */
+
+#if USE_NCURSES
+static double latency_to_ratio (ping_context_t *ctx, /* {{{ */
+               double latency)
+{
+       size_t low;
+       size_t high;
+       size_t index;
+
+       clean_history (ctx);
+
+       /* Not a single packet was received successfully. */
+       if (ctx->history_received == 0)
+               return NAN;
+
+       low = 0;
+       high = ctx->history_received - 1;
+
+       if (latency < ctx->history_by_value[low])
+               return 0.0;
+       else if (latency >= ctx->history_by_value[high])
+               return 100.0;
+
+       /* Do a binary search for the latency. This will work even when the
+        * exact latency is not in the array. If the latency is in the array
+        * multiple times, "low" will be set to the index of the last
+        * occurrence. The value at index "high" will be larger than the
+        * searched for latency (assured by the above "if" block. */
+       while ((high - low) > 1)
+       {
+               index = (high + low) / 2;
+
+               if (ctx->history_by_value[index] > latency)
+                       high = index;
+               else
+                       low = index;
+       }
+
+       assert (ctx->history_by_value[high] > latency);
+       assert (ctx->history_by_value[low] <= latency);
+
+       if (ctx->history_by_value[low] == latency)
+               index = low;
+       else
+               index = high;
+
+       return (((double) (index + 1)) / ((double) ctx->history_received));
+} /* }}} double latency_to_ratio */
+#endif
+
+static double context_get_packet_loss (const ping_context_t *ctx) /* {{{ */
+{
+       if (ctx == NULL)
+               return (-1.0);
+
+       if (ctx->req_sent < 1)
+               return (0.0);
+
+       return (100.0 * (ctx->req_sent - ctx->req_rcvd)
+                       / ((double) ctx->req_sent));
+} /* }}} double context_get_packet_loss */
+
+static int ping_initialize_contexts (pingobj_t *ping) /* {{{ */
+{
+       pingobj_iter_t *iter;
+       int index;
+
+       if (ping == NULL)
+               return (EINVAL);
+
+       index = 0;
+       for (iter = ping_iterator_get (ping);
+                       iter != NULL;
+                       iter = ping_iterator_next (iter))
+       {
+               ping_context_t *context;
+               size_t buffer_size;
+
+               context = context_create ();
+               context->index = index;
+
+               buffer_size = sizeof (context->host);
+               ping_iterator_get_info (iter, PING_INFO_HOSTNAME, context->host, &buffer_size);
+
+               buffer_size = sizeof (context->addr);
+               ping_iterator_get_info (iter, PING_INFO_ADDRESS, context->addr, &buffer_size);
+
+               ping_iterator_set_context (iter, (void *) context);
+
+               index++;
+       }
+
+       return (0);
+} /* }}} int ping_initialize_contexts */
+
+static void usage_exit (const char *name, int status) /* {{{ */
+{
        fprintf (stderr, "Usage: %s [OPTIONS] "
                                "-f filename | host [host [host ...]]\n"
 
@@ -122,30 +432,228 @@ static void usage_exit (const char *name, int status)
                        "  -4|-6        force the use of IPv4 or IPv6\n"
                        "  -c count     number of ICMP packets to send\n"
                        "  -i interval  interval with which to send ICMP packets\n"
+                       "  -w timeout   time to wait for replies, in seconds\n"
                        "  -t ttl       time to live for each ICMP packet\n"
+                       "  -Q qos       Quality of Service (QoS) of outgoing packets\n"
+                       "               Use \"-Q help\" for a list of valid options.\n"
                        "  -I srcaddr   source address\n"
                        "  -D device    outgoing interface name\n"
+                       "  -m mark      mark to set on outgoing packets\n"
                        "  -f filename  filename to read hosts from\n"
+#if USE_NCURSES
+                       "  -u / -U      force / disable UTF-8 output\n"
+                       "  -g graph     graph type to draw\n"
+#endif
+                       "  -P percent   Report the n'th percentile of latency\n"
+                       "  -Z percent   Exit with non-zero exit status if more than this percentage of\n"
+                       "               probes timed out. (default: never)\n"
 
-                       "\noping "PACKAGE_VERSION", http://verplant.org/liboping/\n"
-                       "by Florian octo Forster <octo@verplant.org>\n"
+                       "\noping "PACKAGE_VERSION", http://noping.cc/\n"
+                       "by Florian octo Forster <ff@octo.it>\n"
                        "for contributions see `AUTHORS'\n",
                        name);
        exit (status);
-}
+} /* }}} void usage_exit */
+
+__attribute__((noreturn))
+static void usage_qos_exit (const char *arg, int status) /* {{{ */
+{
+       if (arg != 0)
+               fprintf (stderr, "Invalid QoS argument: \"%s\"\n\n", arg);
+
+       fprintf (stderr, "Valid QoS arguments (option \"-Q\") are:\n"
+                       "\n"
+                       "  Differentiated Services (IPv4 and IPv6, RFC 2474)\n"
+                       "\n"
+                       "    be                     Best Effort (BE, default PHB).\n"
+                       "    ef                     Expedited Forwarding (EF) PHB group (RFC 3246).\n"
+                       "                           (low delay, low loss, low jitter)\n"
+                       "    va                     Voice Admit (VA) DSCP (RFC 5865).\n"
+                       "                           (capacity-admitted traffic)\n"
+                       "    af[1-4][1-3]           Assured Forwarding (AF) PHB group (RFC 2597).\n"
+                       "                           For example: \"af12\" (class 1, precedence 2)\n"
+                       "    cs[0-7]                Class Selector (CS) PHB group (RFC 2474).\n"
+                       "                           For example: \"cs1\" (priority traffic)\n"
+                       "\n"
+                       "  Type of Service (IPv4, RFC 1349, obsolete)\n"
+                       "\n"
+                       "    lowdelay     (%#04x)    minimize delay\n"
+                       "    throughput   (%#04x)    maximize throughput\n"
+                       "    reliability  (%#04x)    maximize reliability\n"
+                       "    mincost      (%#04x)    minimize monetary cost\n"
+                       "\n"
+                       "  Specify manually\n"
+                       "\n"
+                       "    0x00 - 0xff            Hexadecimal numeric specification.\n"
+                       "       0 -  255            Decimal numeric specification.\n"
+                       "\n",
+                       (unsigned int) IPTOS_LOWDELAY,
+                       (unsigned int) IPTOS_THROUGHPUT,
+                       (unsigned int) IPTOS_RELIABILITY,
+                       (unsigned int) IPTOS_MINCOST);
+
+       exit (status);
+} /* }}} void usage_qos_exit */
+
+static int set_opt_send_qos (const char *opt) /* {{{ */
+{
+       if (opt == NULL)
+               return (EINVAL);
+
+       if (strcasecmp ("help", opt) == 0)
+               usage_qos_exit (/* arg = */ NULL, /* status = */ EXIT_SUCCESS);
+       /* DiffServ (RFC 2474): */
+       /* - Best effort (BE) */
+       else if (strcasecmp ("be", opt) == 0)
+               opt_send_qos = 0;
+       /* - Expedited Forwarding (EF, RFC 3246) */
+       else if (strcasecmp ("ef", opt) == 0)
+               opt_send_qos = 0xB8; /* == 0x2E << 2 */
+       /* - Voice Admit (VA, RFC 5865) */
+       else if (strcasecmp ("va", opt) == 0)
+               opt_send_qos = 0xB0; /* == 0x2D << 2 */
+       /* - Assured Forwarding (AF, RFC 2597) */
+       else if ((strncasecmp ("af", opt, strlen ("af")) == 0)
+                       && (strlen (opt) == 4))
+       {
+               uint8_t dscp;
+               uint8_t class = 0;
+               uint8_t prec = 0;
+
+               /* There are four classes, AF1x, AF2x, AF3x, and AF4x. */
+               if (opt[2] == '1')
+                       class = 1;
+               else if (opt[2] == '2')
+                       class = 2;
+               else if (opt[2] == '3')
+                       class = 3;
+               else if (opt[2] == '4')
+                       class = 4;
+               else
+                       usage_qos_exit (/* arg = */ opt, /* status = */ EXIT_SUCCESS);
+
+               /* In each class, there are three precedences, AFx1, AFx2, and AFx3 */
+               if (opt[3] == '1')
+                       prec = 1;
+               else if (opt[3] == '2')
+                       prec = 2;
+               else if (opt[3] == '3')
+                       prec = 3;
+               else
+                       usage_qos_exit (/* arg = */ opt, /* status = */ EXIT_SUCCESS);
+
+               dscp = (8 * class) + (2 * prec);
+               /* The lower two bits are used for Explicit Congestion Notification (ECN) */
+               opt_send_qos = dscp << 2;
+       }
+       /* - Class Selector (CS) */
+       else if ((strncasecmp ("cs", opt, strlen ("cs")) == 0)
+                       && (strlen (opt) == 3))
+       {
+               uint8_t class;
+
+               if ((opt[2] < '0') || (opt[2] > '7'))
+                       usage_qos_exit (/* arg = */ opt, /* status = */ EXIT_FAILURE);
+
+               /* Not exactly legal by the C standard, but I don't know of any
+                * system not supporting this hack. */
+               class = ((uint8_t) opt[2]) - ((uint8_t) '0');
+               opt_send_qos = class << 5;
+       }
+       /* Type of Service (RFC 1349) */
+       else if (strcasecmp ("lowdelay", opt) == 0)
+               opt_send_qos = IPTOS_LOWDELAY;
+       else if (strcasecmp ("throughput", opt) == 0)
+               opt_send_qos = IPTOS_THROUGHPUT;
+       else if (strcasecmp ("reliability", opt) == 0)
+               opt_send_qos = IPTOS_RELIABILITY;
+       else if (strcasecmp ("mincost", opt) == 0)
+               opt_send_qos = IPTOS_MINCOST;
+       /* Numeric value */
+       else
+       {
+               unsigned long value;
+               char *endptr;
+
+               errno = 0;
+               endptr = NULL;
+               value = strtoul (opt, &endptr, /* base = */ 0);
+               if ((errno != 0) || (endptr == opt)
+                               || (endptr == NULL) || (*endptr != 0)
+                               || (value > 0xff))
+                       usage_qos_exit (/* arg = */ opt, /* status = */ EXIT_FAILURE);
+               
+               opt_send_qos = (uint8_t) value;
+       }
 
-static _Bool is_setuid (void)
+       return (0);
+} /* }}} int set_opt_send_qos */
+
+static char *format_qos (uint8_t qos, char *buffer, size_t buffer_size) /* {{{ */
 {
-       return (getuid () != geteuid ());
-}
+       uint8_t dscp;
+       uint8_t ecn;
+       char *dscp_str;
+       char *ecn_str;
+
+       dscp = qos >> 2;
+       ecn = qos & 0x03;
+
+       switch (dscp)
+       {
+               case 0x00: dscp_str = "be";  break;
+               case 0x2e: dscp_str = "ef";  break;
+               case 0x2d: dscp_str = "va";  break;
+               case 0x0a: dscp_str = "af11"; break;
+               case 0x0c: dscp_str = "af12"; break;
+               case 0x0e: dscp_str = "af13"; break;
+               case 0x12: dscp_str = "af21"; break;
+               case 0x14: dscp_str = "af22"; break;
+               case 0x16: dscp_str = "af23"; break;
+               case 0x1a: dscp_str = "af31"; break;
+               case 0x1c: dscp_str = "af32"; break;
+               case 0x1e: dscp_str = "af33"; break;
+               case 0x22: dscp_str = "af41"; break;
+               case 0x24: dscp_str = "af42"; break;
+               case 0x26: dscp_str = "af43"; break;
+               case 0x08: dscp_str = "cs1";  break;
+               case 0x10: dscp_str = "cs2";  break;
+               case 0x18: dscp_str = "cs3";  break;
+               case 0x20: dscp_str = "cs4";  break;
+               case 0x28: dscp_str = "cs5";  break;
+               case 0x30: dscp_str = "cs6";  break;
+               case 0x38: dscp_str = "cs7";  break;
+               default:   dscp_str = NULL;
+       }
+
+       switch (ecn)
+       {
+               case 0x01: ecn_str = ",ecn(1)"; break;
+               case 0x02: ecn_str = ",ecn(0)"; break;
+               case 0x03: ecn_str = ",ce"; break;
+               default:   ecn_str = "";
+       }
+
+       if (dscp_str == NULL)
+               snprintf (buffer, buffer_size, "0x%02x%s", dscp, ecn_str);
+       else
+               snprintf (buffer, buffer_size, "%s%s", dscp_str, ecn_str);
+       buffer[buffer_size - 1] = 0;
 
-static int read_options (int argc, char **argv)
+       return (buffer);
+} /* }}} char *format_qos */
+
+static int read_options (int argc, char **argv) /* {{{ */
 {
        int optchar;
 
        while (1)
        {
-               optchar = getopt (argc, argv, "46c:hi:I:t:f:D:");
+               optchar = getopt (argc, argv, "46c:hi:I:t:Q:f:D:Z:P:m:w:"
+#if USE_NCURSES
+                               "uUg:"
+#endif
+                               );
 
                if (optchar == -1)
                        break;
@@ -162,79 +670,817 @@ static int read_options (int argc, char **argv)
                                        int new_count;
                                        new_count = atoi (optarg);
                                        if (new_count > 0)
+                                       {
                                                opt_count = new_count;
+
+                                               if ((opt_percentile < 0.0) && (opt_count < 20))
+                                                       opt_percentile = 100.0 * (opt_count - 1) / opt_count;
+                                       }
                                        else
                                                fprintf(stderr, "Ignoring invalid count: %s\n",
                                                                optarg);
                                }
                                break;
 
-                       case 'f':
-                               if (is_setuid () && (strcmp ("-", optarg) != 0))
-                               {
-                                       fprintf (stderr, "For security reasons the `-f' option "
-                                                       "is disabled if real and effective "
-                                                       "user IDs don't match. Sorry.\n");
-                               }
-                               else
-                               {
-                                       if (opt_filename != NULL)
-                                               free (opt_filename);
-                                       opt_filename = strdup (optarg);
-                               }
-                               break;
+                       case 'f':
+                               {
+                                       if (opt_filename != NULL)
+                                               free (opt_filename);
+                                       opt_filename = strdup (optarg);
+                               }
+                               break;
+
+                       case 'i':
+                               {
+                                       double new_interval;
+                                       new_interval = atof (optarg);
+                                       if (new_interval < 0.001)
+                                               fprintf (stderr, "Ignoring invalid interval: %s\n",
+                                                               optarg);
+                                       else
+                                               opt_interval = new_interval;
+                               }
+                               break;
+
+                       case 'w':
+                               {
+                                       char *endp = NULL;
+                                       double t = strtod (optarg, &endp);
+                                       if ((optarg[0] != 0) && (endp != NULL) && (*endp == 0))
+                                               opt_timeout = t;
+                                       else
+                                               fprintf (stderr, "Ignoring invalid timeout: %s\n",
+                                                               optarg);
+                               }
+                               break;
+
+                       case 'I':
+                               {
+                                       if (opt_srcaddr != NULL)
+                                               free (opt_srcaddr);
+                                       opt_srcaddr = strdup (optarg);
+                               }
+                               break;
+
+                       case 'D':
+                               opt_device = optarg;
+                               break;
+
+                       case 'm':
+                               opt_mark = optarg;
+                               break;
+
+                       case 't':
+                       {
+                               int new_send_ttl;
+                               new_send_ttl = atoi (optarg);
+                               if ((new_send_ttl > 0) && (new_send_ttl < 256))
+                                       opt_send_ttl = new_send_ttl;
+                               else
+                                       fprintf (stderr, "Ignoring invalid TTL argument: %s\n",
+                                                       optarg);
+                               break;
+                       }
+
+                       case 'Q':
+                               set_opt_send_qos (optarg);
+                               break;
+
+                       case 'P':
+                               {
+                                       double new_percentile;
+                                       new_percentile = atof (optarg);
+                                       if (isnan (new_percentile)
+                                                       || (new_percentile < 0.1)
+                                                       || (new_percentile > 100.0))
+                                               fprintf (stderr, "Ignoring invalid percentile: %s\n",
+                                                               optarg);
+                                       else
+                                               opt_percentile = new_percentile;
+                               }
+                               break;
+
+#if USE_NCURSES
+                       case 'g':
+                               if (strcasecmp ("none", optarg) == 0)
+                                       opt_show_graph = 0;
+                               else if (strcasecmp ("prettyping", optarg) == 0)
+                                       opt_show_graph = 1;
+                               else if (strcasecmp ("histogram", optarg) == 0)
+                                       opt_show_graph = 2;
+                               else if (strcasecmp ("boxplot", optarg) == 0)
+                                       opt_show_graph = 3;
+                               else
+                                       fprintf (stderr, "Unknown graph option: %s\n", optarg);
+                               break;
+
+                       case 'u':
+                               opt_utf8 = 2;
+                               break;
+                       case 'U':
+                               opt_utf8 = 1;
+                               break;
+#endif
+
+                       case 'Z':
+                       {
+                               char *endptr = NULL;
+                               double tmp;
+
+                               errno = 0;
+                               tmp = strtod (optarg, &endptr);
+                               if ((errno != 0) || (endptr == NULL) || (*endptr != 0) || (tmp < 0.0) || (tmp > 100.0))
+                               {
+                                       fprintf (stderr, "Ignoring invalid -Z argument: %s\n", optarg);
+                                       fprintf (stderr, "The \"-Z\" option requires a numeric argument between 0 and 100.\n");
+                               }
+                               else
+                                       opt_exit_status_threshold = tmp / 100.0;
+
+                               break;
+                       }
+
+                       case 'h':
+                               usage_exit (argv[0], 0);
+                               break;
+
+                       default:
+                               usage_exit (argv[0], 1);
+               }
+       }
+
+       if (opt_percentile <= 0.0)
+               opt_percentile = OPING_DEFAULT_PERCENTILE;
+
+       return (optind);
+} /* }}} read_options */
+
+static void time_normalize (struct timespec *ts) /* {{{ */
+{
+       while (ts->tv_nsec < 0)
+       {
+               if (ts->tv_sec == 0)
+               {
+                       ts->tv_nsec = 0;
+                       return;
+               }
+
+               ts->tv_sec  -= 1;
+               ts->tv_nsec += 1000000000;
+       }
+
+       while (ts->tv_nsec >= 1000000000)
+       {
+               ts->tv_sec  += 1;
+               ts->tv_nsec -= 1000000000;
+       }
+} /* }}} void time_normalize */
+
+static void time_calc (struct timespec *ts_dest, /* {{{ */
+               const struct timespec *ts_int,
+               const struct timeval  *tv_begin,
+               const struct timeval  *tv_end)
+{
+       ts_dest->tv_sec = tv_begin->tv_sec + ts_int->tv_sec;
+       ts_dest->tv_nsec = (tv_begin->tv_usec * 1000) + ts_int->tv_nsec;
+       time_normalize (ts_dest);
+
+       /* Assure that `(begin + interval) > end'.
+        * This may seem overly complicated, but `tv_sec' is of type `time_t'
+        * which may be `unsigned. *sigh* */
+       if ((tv_end->tv_sec > ts_dest->tv_sec)
+                       || ((tv_end->tv_sec == ts_dest->tv_sec)
+                               && ((tv_end->tv_usec * 1000) > ts_dest->tv_nsec)))
+       {
+               ts_dest->tv_sec  = 0;
+               ts_dest->tv_nsec = 0;
+               return;
+       }
+
+       ts_dest->tv_sec = ts_dest->tv_sec - tv_end->tv_sec;
+       ts_dest->tv_nsec = ts_dest->tv_nsec - (tv_end->tv_usec * 1000);
+       time_normalize (ts_dest);
+} /* }}} void time_calc */
+
+#if USE_NCURSES
+static _Bool has_utf8() /* {{{ */
+{
+# if HAVE_NCURSESW_NCURSES_H
+       if (!opt_utf8)
+       {
+               /* Automatically determine */
+               if (strcasecmp ("UTF-8", nl_langinfo (CODESET)) == 0)
+                       opt_utf8 = 2;
+               else
+                       opt_utf8 = 1;
+       }
+       return ((_Bool) (opt_utf8 - 1));
+# else
+       return (0);
+# endif
+} /* }}} _Bool has_utf8 */
+
+static int update_graph_boxplot (ping_context_t *ctx) /* {{{ */
+{
+       uint32_t *counters;
+       double *ratios;
+       size_t i;
+       size_t x_max;
+       size_t x;
+
+       clean_history (ctx);
+
+       if (ctx->history_received == 0)
+               return (ENOENT);
+
+       x_max = (size_t) getmaxx (ctx->window);
+       if (x_max <= 8)
+               return (EINVAL);
+       x_max -= 4;
+
+       counters = calloc (x_max, sizeof (*counters));
+       ratios = calloc (x_max, sizeof (*ratios));
+
+       /* Bucketize */
+       for (i = 0; i < ctx->history_received; i++)
+       {
+               double latency = ctx->history_by_value[i] / 1000.0;
+               size_t index = (size_t) (((double) x_max) * latency / opt_interval);
+
+               if (index >= x_max)
+                       index = x_max - 1;
+
+               counters[index]++;
+       }
+
+       /* Sum and calc ratios */
+       ratios[0] = ((double) counters[0]) / ((double) ctx->history_received);
+       for (x = 1; x < x_max; x++)
+       {
+               counters[x] += counters[x - 1];
+               ratios[x] = ((double) counters[x]) / ((double) ctx->history_received);
+       }
+
+       for (x = 0; x < x_max; x++)
+       {
+               int symbol = ' ';
+               _Bool reverse = 0;
+
+               if (x == 0)
+               {
+                       if (ratios[x] >= 0.5)
+                       {
+                               symbol = BOXPLOT_MEDIAN;
+                               reverse = 1;
+                       }
+                       else if (ratios[x] > 0.25)
+                       {
+                               symbol = BOXPLOT_BOX;
+                               reverse = 1;
+                       }
+                       else if (ratios[x] > 0.025)
+                               symbol = BOXPLOT_WHISKER_BAR;
+                       else
+                               symbol = ' '; /* NOP */
+               }
+               else /* (x != 0) */
+               {
+                       if ((ratios[x - 1] < 0.5) && (ratios[x] >= 0.5))
+                       {
+                               symbol = BOXPLOT_MEDIAN;
+                               reverse = 1;
+                       }
+                       else if (((ratios[x] >= 0.25) && (ratios[x] <= 0.75))
+                                       || ((ratios[x - 1] < 0.75) && (ratios[x] > 0.75)))
+                       {
+                               symbol = BOXPLOT_BOX;
+                               reverse = 1;
+                       }
+                       else if ((ratios[x] < 0.5) && (ratios[x] >= 0.025))
+                       {
+                               if (ratios[x - 1] < 0.025)
+                                       symbol = BOXPLOT_WHISKER_LEFT_END;
+                               else
+                                       symbol = BOXPLOT_WHISKER_BAR;
+                       }
+                       else if ((ratios[x] > .5) && (ratios[x] < 0.975))
+                       {
+                               symbol = BOXPLOT_WHISKER_BAR;
+                       }
+                       else if ((ratios[x] >= 0.975) && (ratios[x - 1] < 0.975))
+                               symbol = BOXPLOT_WHISKER_RIGHT_END;
+               }
+
+               if (reverse)
+                       wattron (ctx->window, A_REVERSE);
+               mvwaddch (ctx->window, /* y = */ 3, /* x = */ (int) (x + 2), symbol);
+               // mvwprintw (ctx->window, /* y = */ 3, /* x = */ (int) (x + 2), symbol);
+               if (reverse)
+                       wattroff (ctx->window, A_REVERSE);
+       }
+
+       free (counters);
+       free (ratios);
+       return (0);
+} /* }}} int update_graph_boxplot */
+
+static int update_graph_prettyping (ping_context_t *ctx, /* {{{ */
+               double latency, unsigned int sequence)
+{
+       size_t x;
+       size_t x_max;
+       size_t history_offset;
+
+       x_max = (size_t) getmaxx (ctx->window);
+       if (x_max <= 4)
+               return (EINVAL);
+       x_max -= 4;
+
+       /* Determine the first index in the history we need to draw
+        * the graph. */
+       history_offset = 0;
+       if (((size_t) x_max) < ctx->history_size) /* window is smaller than history */
+       {
+               if (ctx->history_index > x_max)
+                       history_offset = ctx->history_index - x_max;
+               else /* wrap around */
+                       history_offset = ctx->history_index + ctx->history_size - x_max;
+       }
+       else /* window is larger than history */
+       {
+               if (ctx->history_index != ctx->history_size) /* no longer growing. */
+                       history_offset = ctx->history_index;
+               else /* start-up */
+                       history_offset = 0;
+       }
+
+       for (x = 0; x < x_max; x++)
+       {
+               size_t index;
+               double latency;
+
+               int color = OPING_RED;
+               char const *symbol = "!";
+               int symbolc = '!';
+
+               if (x >= ctx->history_size)
+               {
+                       mvwaddch (ctx->window, /* y = */ 3, /* x = */ x + 2, ' ');
+                       continue;
+               }
+
+               index = (history_offset + x) % ctx->history_size;
+               latency = ctx->history_by_time[index];
+
+               if (latency >= 0.0)
+               {
+                       double ratio;
+
+                       size_t symbols_num = hist_symbols_acs_num;
+                       size_t colors_num = 1;
+
+                       size_t index_symbols;
+                       size_t index_colors;
+                       size_t intensity;
+
+                       /* latency is in milliseconds, opt_interval is in seconds. */
+                       ratio = (latency * 0.001) / opt_interval;
+                       if (ratio > 1) {
+                               ratio = 1.0;
+                       }
+
+                       if (has_utf8 ())
+                               symbols_num = hist_symbols_utf8_num;
+
+                       if (has_colors () == TRUE)
+                               colors_num = hist_colors_num;
+
+                       intensity = (size_t) (ratio * ((double) (symbols_num * colors_num)));
+                       if (intensity >= (symbols_num * colors_num))
+                               intensity = (symbols_num * colors_num) - 1;
+
+                       index_symbols = intensity % symbols_num;
+                       assert (index_symbols < symbols_num);
+
+                       index_colors = intensity / symbols_num;
+                       assert (index_colors < colors_num);
+
+                       if (has_utf8())
+                       {
+                               color = hist_colors_utf8[index_colors];
+                               symbol = hist_symbols_utf8[index_symbols];
+                       }
+                       else
+                       {
+                               color = hist_colors_acs[index_colors];
+                               symbolc = hist_symbols_acs[index_symbols] | A_ALTCHARSET;
+                       }
+               }
+               else /* if (!(latency >= 0.0)) */
+                       wattron (ctx->window, A_BOLD);
+
+               if (has_colors () == TRUE)
+                       wattron (ctx->window, COLOR_PAIR(color));
+
+               if (has_utf8())
+                       mvwprintw (ctx->window, /* y = */ 3, /* x = */ x + 2, symbol);
+               else
+                       mvwaddch (ctx->window, /* y = */ 3, /* x = */ x + 2, symbolc);
+
+               if (has_colors () == TRUE)
+                       wattroff (ctx->window, COLOR_PAIR(color));
+
+               /* Use negation here to handle NaN correctly. */
+               if (!(latency >= 0.0))
+                       wattroff (ctx->window, A_BOLD);
+       } /* for (x) */
+
+       return (0);
+} /* }}} int update_graph_prettyping */
+
+static int update_graph_histogram (ping_context_t *ctx) /* {{{ */
+{
+       uint32_t *counters;
+       uint32_t *accumulated;
+       uint32_t max;
+       size_t i;
+       size_t x_max;
+       size_t x;
+
+       size_t symbols_num = hist_symbols_acs_num;
+
+       clean_history (ctx);
+
+       if (ctx->history_received == 0)
+               return (ENOENT);
+
+       if (has_utf8 ())
+               symbols_num = hist_symbols_utf8_num;
+
+       x_max = (size_t) getmaxx (ctx->window);
+       if (x_max <= 4)
+               return (EINVAL);
+       x_max -= 4;
+
+       counters = calloc (x_max, sizeof (*counters));
+       accumulated = calloc (x_max, sizeof (*accumulated));
+
+       /* Bucketize */
+       max = 0;
+       for (i = 0; i < ctx->history_received; i++)
+       {
+               double latency = ctx->history_by_value[i] / 1000.0;
+               size_t index = (size_t) (((double) x_max) * latency / opt_interval);
+
+               if (index >= x_max)
+                       index = x_max - 1;
+
+               counters[index]++;
+               if (max < counters[index])
+                       max = counters[index];
+       }
+
+       /* Sum */
+       accumulated[0] = counters[0];
+       for (x = 1; x < x_max; x++)
+               accumulated[x] = counters[x] + accumulated[x - 1];
+
+       /* Calculate ratios */
+       for (x = 0; x < x_max; x++)
+       {
+               double height = ((double) counters[x]) / ((double) max);
+               double ratio_this = ((double) accumulated[x]) / ((double) ctx->history_received);
+               double ratio_prev = 0.0;
+               size_t index;
+               int color = 0;
+
+               index = (size_t) (height * ((double) symbols_num));
+               if (index >= symbols_num)
+                       index = symbols_num - 1;
+
+               if (x > 0)
+                       ratio_prev = ((double) accumulated[x - 1]) / ((double) ctx->history_received);
+
+               if (has_colors () == TRUE)
+               {
+                       if ((ratio_this <= threshold_green)
+                                       || ((ratio_prev < threshold_green)
+                                               && (ratio_this > threshold_green)))
+                               color = OPING_GREEN;
+                       else if ((ratio_this <= threshold_yellow)
+                                       || ((ratio_prev < threshold_yellow)
+                                               && (ratio_this > threshold_yellow)))
+                               color = OPING_YELLOW;
+                       else
+                               color = OPING_RED;
+
+                       wattron (ctx->window, COLOR_PAIR(color));
+               }
+
+               if (counters[x] == 0)
+                       mvwaddch (ctx->window, /* y = */ 3, /* x = */ x + 2, ' ');
+               else if (has_utf8 ())
+                       mvwprintw (ctx->window, /* y = */ 3, /* x = */ x + 2,
+                                       hist_symbols_utf8[index]);
+               else
+                       mvwaddch (ctx->window, /* y = */ 3, /* x = */ x + 2,
+                                       hist_symbols_acs[index] | A_ALTCHARSET);
+
+               if (has_colors () == TRUE)
+                       wattroff (ctx->window, COLOR_PAIR(color));
+
+       }
+
+       free (accumulated);
+       return (0);
+} /* }}} int update_graph_histogram */
+
+static int update_stats_from_context (ping_context_t *ctx, pingobj_iter_t *iter) /* {{{ */
+{
+       double latency = -1.0;
+       size_t buffer_len = sizeof (latency);
+
+       ping_iterator_get_info (iter, PING_INFO_LATENCY,
+                       &latency, &buffer_len);
+
+       unsigned int sequence = 0;
+       buffer_len = sizeof (sequence);
+       ping_iterator_get_info (iter, PING_INFO_SEQUENCE,
+                       &sequence, &buffer_len);
+
+
+       if ((ctx == NULL) || (ctx->window == NULL))
+               return (EINVAL);
+
+       /* werase (ctx->window); */
+
+       box (ctx->window, 0, 0);
+       wattron (ctx->window, A_BOLD);
+       mvwprintw (ctx->window, /* y = */ 0, /* x = */ 5,
+                       " %s ", ctx->host);
+       wattroff (ctx->window, A_BOLD);
+       wprintw (ctx->window, "ping statistics ");
+       mvwprintw (ctx->window, /* y = */ 1, /* x = */ 2,
+                       "%i packets transmitted, %i received, %.2f%% packet "
+                       "loss, time %.1fms",
+                       ctx->req_sent, ctx->req_rcvd,
+                       context_get_packet_loss (ctx),
+                       ctx->latency_total);
+       if (ctx->req_rcvd != 0)
+       {
+               double min;
+               double median;
+               double max;
+               double percentile;
+
+               min = percentile_to_latency (ctx, 0.0);
+               median = percentile_to_latency (ctx, 50.0);
+               max = percentile_to_latency (ctx, 100.0);
+               percentile = percentile_to_latency (ctx, opt_percentile);
+
+               mvwprintw (ctx->window, /* y = */ 2, /* x = */ 2,
+                               "RTT[ms]: min = %.0f, median = %.0f, p(%.0f) = %.0f, max = %.0f  ",
+                               min, median, opt_percentile, percentile, max);
+       }
+
+       if (opt_show_graph == 1)
+               update_graph_prettyping (ctx, latency, sequence);
+       else if (opt_show_graph == 2)
+               update_graph_histogram (ctx);
+       else if (opt_show_graph == 3)
+               update_graph_boxplot (ctx);
+
+       wrefresh (ctx->window);
+
+       return (0);
+} /* }}} int update_stats_from_context */
+
+static int on_resize (pingobj_t *ping) /* {{{ */
+{
+       pingobj_iter_t *iter;
+       int width = 0;
+       int height = 0;
+       int main_win_height;
+       int box_height = (opt_show_graph == 0) ? 4 : 5;
+
+       getmaxyx (stdscr, height, width);
+       if ((height < 1) || (width < 1))
+               return (EINVAL);
+
+       main_win_height = height - (box_height * host_num);
+       wresize (main_win, main_win_height, /* width = */ width);
+       /* Allow scrolling */
+       scrollok (main_win, TRUE);
+       /* wsetscrreg (main_win, 0, main_win_height - 1); */
+       /* Allow hardware accelerated scrolling. */
+       idlok (main_win, TRUE);
+       wrefresh (main_win);
+
+       for (iter = ping_iterator_get (ping);
+                       iter != NULL;
+                       iter = ping_iterator_next (iter))
+       {
+               ping_context_t *context;
+
+               context = ping_iterator_get_context (iter);
+               if (context == NULL)
+                       continue;
+
+               if (context->window != NULL)
+               {
+                       delwin (context->window);
+                       context->window = NULL;
+               }
+               context->window = newwin (/* height = */ box_height,
+                               /* width = */ width,
+                               /* y = */ main_win_height + (box_height * context->index),
+                               /* x = */ 0);
+       }
+
+       return (0);
+} /* }}} */
+
+static int check_resize (pingobj_t *ping) /* {{{ */
+{
+       int need_resize = 0;
+
+       while (42)
+       {
+               int key = wgetch (stdscr);
+               if (key == ERR)
+                       break;
+               else if (key == KEY_RESIZE)
+                       need_resize = 1;
+               else if (key == 'g')
+               {
+                       if (opt_show_graph == 3)
+                               opt_show_graph = 1;
+                       else if (opt_show_graph > 0)
+                               opt_show_graph++;
+               }
+       }
+
+       if (need_resize)
+               return (on_resize (ping));
+       else
+               return (0);
+} /* }}} int check_resize */
+
+static int pre_loop_hook (pingobj_t *ping) /* {{{ */
+{
+       pingobj_iter_t *iter;
+       int width = 0;
+       int height = 0;
+       int main_win_height;
+       int box_height = (opt_show_graph == 0) ? 4 : 5;
+
+       initscr ();
+       cbreak ();
+       noecho ();
+       nodelay (stdscr, TRUE);
+
+       getmaxyx (stdscr, height, width);
+       if ((height < 1) || (width < 1))
+               return (EINVAL);
+
+       if (has_colors () == TRUE)
+       {
+               start_color ();
+               init_pair (OPING_GREEN,  COLOR_GREEN,  /* default = */ 0);
+               init_pair (OPING_YELLOW, COLOR_YELLOW, /* default = */ 0);
+               init_pair (OPING_RED,    COLOR_RED,    /* default = */ 0);
+               init_pair (OPING_GREEN_HIST,  COLOR_GREEN,  COLOR_BLACK);
+               init_pair (OPING_YELLOW_HIST, COLOR_YELLOW, COLOR_GREEN);
+               init_pair (OPING_RED_HIST,    COLOR_RED,    COLOR_YELLOW);
+       }
+
+       main_win_height = height - (box_height * host_num);
+       main_win = newwin (/* height = */ main_win_height,
+                       /* width = */ width,
+                       /* y = */ 0, /* x = */ 0);
+       /* Allow scrolling */
+       scrollok (main_win, TRUE);
+       /* wsetscrreg (main_win, 0, main_win_height - 1); */
+       /* Allow hardware accelerated scrolling. */
+       idlok (main_win, TRUE);
+       wmove (main_win, /* y = */ main_win_height - 1, /* x = */ 0);
+       wrefresh (main_win);
+
+       for (iter = ping_iterator_get (ping);
+                       iter != NULL;
+                       iter = ping_iterator_next (iter))
+       {
+               ping_context_t *context;
+
+               context = ping_iterator_get_context (iter);
+               if (context == NULL)
+                       continue;
+
+               if (context->window != NULL)
+               {
+                       delwin (context->window);
+                       context->window = NULL;
+               }
+               context->window = newwin (/* height = */ box_height,
+                               /* width = */ width,
+                               /* y = */ main_win_height + (box_height * context->index),
+                               /* x = */ 0);
+       }
+
+
+       /* Don't know what good this does exactly, but without this code
+        * "check_resize" will be called right after startup and *somehow*
+        * this leads to display errors. If we purge all initial characters
+        * here, the problem goes away. "wgetch" is non-blocking due to
+        * "nodelay" (see above). */
+       while (wgetch (stdscr) != ERR)
+       {
+               /* eat up characters */;
+       }
+
+       return (0);
+} /* }}} int pre_loop_hook */
+
+static int pre_sleep_hook (pingobj_t *ping) /* {{{ */
+{
+       return (check_resize (ping));
+} /* }}} int pre_sleep_hook */
+
+static int post_sleep_hook (pingobj_t *ping) /* {{{ */
+{
+       return (check_resize (ping));
+} /* }}} int pre_sleep_hook */
+#else /* if !USE_NCURSES */
+static int pre_loop_hook (pingobj_t *ping) /* {{{ */
+{
+       pingobj_iter_t *iter;
+
+       for (iter = ping_iterator_get (ping);
+                       iter != NULL;
+                       iter = ping_iterator_next (iter))
+       {
+               ping_context_t *ctx;
+               size_t buffer_size;
+
+               ctx = ping_iterator_get_context (iter);
+               if (ctx == NULL)
+                       continue;
 
-                       case 'i':
-                               {
-                                       double new_interval;
-                                       new_interval = atof (optarg);
-                                       if (new_interval < 0.001)
-                                               fprintf (stderr, "Ignoring invalid interval: %s\n",
-                                                               optarg);
-                                       else
-                                               opt_interval = new_interval;
-                               }
-                               break;
-                       case 'I':
-                               {
-                                       if (opt_srcaddr != NULL)
-                                               free (opt_srcaddr);
-                                       opt_srcaddr = strdup (optarg);
-                               }
-                               break;
+               buffer_size = 0;
+               ping_iterator_get_info (iter, PING_INFO_DATA, NULL, &buffer_size);
 
-                       case 'D':
-                               opt_device = optarg;
-                               break;
+               printf ("PING %s (%s) %zu bytes of data.\n",
+                               ctx->host, ctx->addr, buffer_size);
+       }
 
-                       case 't':
-                       {
-                               int new_send_ttl;
-                               new_send_ttl = atoi (optarg);
-                               if ((new_send_ttl > 0) && (new_send_ttl < 256))
-                                       opt_send_ttl = new_send_ttl;
-                               else
-                                       fprintf (stderr, "Ignoring invalid TTL argument: %s\n",
-                                                       optarg);
-                               break;
-                       }
+       return (0);
+} /* }}} int pre_loop_hook */
 
-                       case 'h':
-                               usage_exit (argv[0], 0);
-                               break;
-                       default:
-                               usage_exit (argv[0], 1);
-               }
+static int pre_sleep_hook (__attribute__((unused)) pingobj_t *ping) /* {{{ */
+{
+       fflush (stdout);
+
+       return (0);
+} /* }}} int pre_sleep_hook */
+
+static int post_sleep_hook (__attribute__((unused)) pingobj_t *ping) /* {{{ */
+{
+       return (0);
+} /* }}} int post_sleep_hook */
+#endif
+
+static void update_context (ping_context_t *ctx, double latency) /* {{{ */
+{
+       ctx->req_sent++;
+
+       if (latency > 0.0)
+       {
+               ctx->req_rcvd++;
+               ctx->latency_total += latency;
+       }
+       else
+       {
+               latency = NAN;
        }
 
-       return (optind);
-}
+       ctx->history_by_time[ctx->history_index] = latency;
+
+       ctx->history_dirty = 1;
+
+       /* Update index and size. */
+       ctx->history_index = (ctx->history_index + 1) % HISTORY_SIZE_MAX;
+       if (ctx->history_size < HISTORY_SIZE_MAX)
+               ctx->history_size++;
+} /* }}} void update_context */
 
-static void print_host (pingobj_iter_t *iter)
+static void update_host_hook (pingobj_iter_t *iter, /* {{{ */
+               __attribute__((unused)) int index)
 {
        double          latency;
        unsigned int    sequence;
        int             recv_ttl;
+       uint8_t         recv_qos;
+       char            recv_qos_str[16];
        size_t          buffer_len;
        size_t          data_len;
        ping_context_t *context;
@@ -254,85 +1500,160 @@ static void print_host (pingobj_iter_t *iter)
        ping_iterator_get_info (iter, PING_INFO_RECV_TTL,
                        &recv_ttl, &buffer_len);
 
+       recv_qos = 0;
+       buffer_len = sizeof (recv_qos);
+       ping_iterator_get_info (iter, PING_INFO_RECV_QOS,
+                       &recv_qos, &buffer_len);
+
        data_len = 0;
        ping_iterator_get_info (iter, PING_INFO_DATA,
                        NULL, &data_len);
 
        context = (ping_context_t *) ping_iterator_get_context (iter);
 
-       context->req_sent++;
-       if (latency > 0.0)
-       {
-               context->req_rcvd++;
-               context->latency_total += latency;
-               context->latency_total_square += (latency * latency);
+#if USE_NCURSES
+# define HOST_PRINTF(...) wprintw(main_win, __VA_ARGS__)
+#else
+# define HOST_PRINTF(...) printf(__VA_ARGS__)
+#endif
 
-               if ((context->latency_max < 0.0) || (context->latency_max < latency))
-                       context->latency_max = latency;
-               if ((context->latency_min < 0.0) || (context->latency_min > latency))
-                       context->latency_min = latency;
+       update_context (context, latency);
 
-               printf ("%zu bytes from %s (%s): icmp_seq=%u ttl=%i time=%.2f ms\n",
+       if (latency > 0.0)
+       {
+#if USE_NCURSES
+               if (has_colors () == TRUE)
+               {
+                       double ratio;
+                       int color = OPING_GREEN;
+
+                       ratio = latency_to_ratio (context, latency);
+                       if (ratio < threshold_green)
+                               color = OPING_GREEN;
+                       else if (ratio < threshold_yellow)
+                               color = OPING_YELLOW;
+                       else
+                               color = OPING_RED;
+
+                       HOST_PRINTF ("%zu bytes from %s (%s): icmp_seq=%u ttl=%i ",
+                                       data_len, context->host, context->addr,
+                                       sequence, recv_ttl,
+                                       format_qos (recv_qos, recv_qos_str, sizeof (recv_qos_str)));
+                       if ((recv_qos != 0) || (opt_send_qos != 0))
+                       {
+                               HOST_PRINTF ("qos=%s ",
+                                               format_qos (recv_qos, recv_qos_str, sizeof (recv_qos_str)));
+                       }
+                       HOST_PRINTF ("time=");
+                       wattron (main_win, COLOR_PAIR(color));
+                       HOST_PRINTF ("%.2f", latency);
+                       wattroff (main_win, COLOR_PAIR(color));
+                       HOST_PRINTF (" ms\n");
+               }
+               else
+               {
+#endif
+               HOST_PRINTF ("%zu bytes from %s (%s): icmp_seq=%u ttl=%i ",
                                data_len,
                                context->host, context->addr,
-                               sequence, recv_ttl, latency);
+                               sequence, recv_ttl);
+               if ((recv_qos != 0) || (opt_send_qos != 0))
+               {
+                       HOST_PRINTF ("qos=%s ",
+                                       format_qos (recv_qos, recv_qos_str, sizeof (recv_qos_str)));
+               }
+               HOST_PRINTF ("time=%.2f ms\n", latency);
+#if USE_NCURSES
+               }
+#endif
        }
-       else
+       else /* if (!(latency > 0.0)) */
        {
-               printf ("echo reply from %s (%s): icmp_seq=%u timeout\n",
+#if USE_NCURSES
+               if (has_colors () == TRUE)
+               {
+                       HOST_PRINTF ("echo reply from %s (%s): icmp_seq=%u ",
+                                       context->host, context->addr,
+                                       sequence);
+                       wattron (main_win, COLOR_PAIR(OPING_RED) | A_BOLD);
+                       HOST_PRINTF ("timeout");
+                       wattroff (main_win, COLOR_PAIR(OPING_RED) | A_BOLD);
+                       HOST_PRINTF ("\n");
+               }
+               else
+               {
+#endif
+               HOST_PRINTF ("echo reply from %s (%s): icmp_seq=%u timeout\n",
                                context->host, context->addr,
                                sequence);
+#if USE_NCURSES
+               }
+#endif
        }
-}
 
-static void time_normalize (struct timespec *ts)
+#if USE_NCURSES
+       update_stats_from_context (context, iter);
+       wrefresh (main_win);
+#endif
+} /* }}} void update_host_hook */
+
+/* Prints statistics for each host, cleans up the contexts and returns the
+ * number of hosts which failed to return more than the fraction
+ * opt_exit_status_threshold of pings. */
+static int post_loop_hook (pingobj_t *ping) /* {{{ */
 {
-       while (ts->tv_nsec < 0)
-       {
-               if (ts->tv_sec == 0)
-               {
-                       ts->tv_nsec = 0;
-                       return;
-               }
+       pingobj_iter_t *iter;
+       int failure_count = 0;
 
-               ts->tv_sec  -= 1;
-               ts->tv_nsec += 1000000000;
-       }
+#if USE_NCURSES
+       endwin ();
+#endif
 
-       while (ts->tv_nsec >= 1000000000)
+       for (iter = ping_iterator_get (ping);
+                       iter != NULL;
+                       iter = ping_iterator_next (iter))
        {
-               ts->tv_sec  += 1;
-               ts->tv_nsec -= 1000000000;
-       }
-}
+               ping_context_t *context;
 
-static void time_calc (struct timespec *ts_dest,
-               const struct timespec *ts_int,
-               const struct timeval  *tv_begin,
-               const struct timeval  *tv_end)
-{
-       ts_dest->tv_sec = tv_begin->tv_sec + ts_int->tv_sec;
-       ts_dest->tv_nsec = (tv_begin->tv_usec * 1000) + ts_int->tv_nsec;
-       time_normalize (ts_dest);
+               context = ping_iterator_get_context (iter);
 
-       /* Assure that `(begin + interval) > end'.
-        * This may seem overly complicated, but `tv_sec' is of type `time_t'
-        * which may be `unsigned. *sigh* */
-       if ((tv_end->tv_sec > ts_dest->tv_sec)
-                       || ((tv_end->tv_sec == ts_dest->tv_sec)
-                               && ((tv_end->tv_usec * 1000) > ts_dest->tv_nsec)))
-       {
-               ts_dest->tv_sec  = 0;
-               ts_dest->tv_nsec = 0;
-               return;
+               printf ("\n--- %s ping statistics ---\n"
+                               "%i packets transmitted, %i received, %.2f%% packet loss, time %.1fms\n",
+                               context->host, context->req_sent, context->req_rcvd,
+                               context_get_packet_loss (context),
+                               context->latency_total);
+
+               {
+                       double pct_failed = 1.0 - (((double) context->req_rcvd)
+                                       / ((double) context->req_sent));
+                       if (pct_failed > opt_exit_status_threshold)
+                               failure_count++;
+               }
+
+               if (context->req_rcvd != 0)
+               {
+                       double min;
+                       double median;
+                       double max;
+                       double percentile;
+
+                       min = percentile_to_latency (context, 0.0);
+                       median = percentile_to_latency (context, 50.0);
+                       max = percentile_to_latency (context, 100.0);
+                       percentile = percentile_to_latency (context, opt_percentile);
+
+                       printf ("RTT[ms]: min = %.0f, median = %.0f, p(%.0f) = %.0f, max = %.0f\n",
+                                       min, median, opt_percentile, percentile, max);
+               }
+
+               ping_iterator_set_context (iter, NULL);
+               context_destroy (context);
        }
 
-       ts_dest->tv_sec = ts_dest->tv_sec - tv_end->tv_sec;
-       ts_dest->tv_nsec = ts_dest->tv_nsec - (tv_end->tv_usec * 1000);
-       time_normalize (ts_dest);
-}
+       return (failure_count);
+} /* }}} int post_loop_hook */
 
-int main (int argc, char **argv)
+int main (int argc, char **argv) /* {{{ */
 {
        pingobj_t      *ping;
        pingobj_iter_t *iter;
@@ -346,17 +1667,43 @@ int main (int argc, char **argv)
 
        int optind;
        int i;
+       int status;
+#if _POSIX_SAVED_IDS
+       uid_t saved_set_uid;
+
+       /* Save the old effective user id */
+       saved_set_uid = geteuid ();
+       /* Set the effective user ID to the real user ID without changing the
+        * saved set-user ID */
+       status = seteuid (getuid ());
+       if (status != 0)
+       {
+               fprintf (stderr, "Temporarily dropping privileges "
+                               "failed: %s\n", strerror (errno));
+               exit (EXIT_FAILURE);
+       }
+#endif
 
+       setlocale(LC_ALL, "");
        optind = read_options (argc, argv);
 
-       if ((optind >= argc) && (opt_filename == NULL)) {
-               usage_exit (argv[0], 1);
+#if !_POSIX_SAVED_IDS
+       /* Cannot temporarily drop privileges -> reject every file but "-". */
+       if ((opt_filename != NULL)
+                       && (strcmp ("-", opt_filename) != 0)
+                       && (getuid () != geteuid ()))
+       {
+               fprintf (stderr, "Your real and effective user IDs don't "
+                               "match. Reading from a file (option '-f')\n"
+                               "is therefore too risky. You can still read "
+                               "from STDIN using '-f -' if you like.\n"
+                               "Sorry.\n");
+               exit (EXIT_FAILURE);
        }
+#endif
 
-       if (geteuid () != 0)
-       {
-               fprintf (stderr, "Need superuser privileges to open a RAW socket. Sorry.\n");
-               return (1);
+       if ((optind >= argc) && (opt_filename == NULL)) {
+               usage_exit (argv[0], 1);
        }
 
        if ((ping = ping_construct ()) == NULL)
@@ -371,6 +1718,12 @@ int main (int argc, char **argv)
                                opt_send_ttl, ping_get_error (ping));
        }
 
+       if (ping_setopt (ping, PING_OPT_QOS, &opt_send_qos) != 0)
+       {
+               fprintf (stderr, "Setting TOS to %i failed: %s\n",
+                               opt_send_qos, ping_get_error (ping));
+       }
+
        {
                double temp_sec;
                double temp_nsec;
@@ -382,6 +1735,12 @@ int main (int argc, char **argv)
                /* printf ("ts_int = %i.%09li\n", (int) ts_int.tv_sec, ts_int.tv_nsec); */
        }
 
+       if (ping_setopt (ping, PING_OPT_TIMEOUT, (void*)(&opt_timeout)) != 0)
+       {
+               fprintf (stderr, "Setting timeout failed: %s\n",
+                               ping_get_error (ping));
+       }
+
        if (opt_addrfamily != PING_DEF_AF)
                ping_setopt (ping, PING_OPT_AF, (void *) &opt_addrfamily);
 
@@ -403,6 +1762,23 @@ int main (int argc, char **argv)
                }
        }
 
+       if(opt_mark != NULL)
+       {
+               char *endp;
+               int mark = strtoul(opt_mark, &endp, 0);
+               if(opt_mark[0] != '\0' && *endp == '\0')
+               {
+                       if(ping_setopt(ping, PING_OPT_MARK, (void*)(&mark)) != 0)
+                       {
+                               fprintf (stderr, "Setting mark failed: %s\n",
+                                       ping_get_error (ping));
+                       }
+               }
+               else{
+                       fprintf(stderr, "Ignoring invalid mark: %s\n", optarg);
+               }
+       }
+
        if (opt_filename != NULL)
        {
                FILE *infile;
@@ -424,6 +1800,17 @@ int main (int argc, char **argv)
                        return (1);
                }
 
+#if _POSIX_SAVED_IDS
+               /* Regain privileges */
+               status = seteuid (saved_set_uid);
+               if (status != 0)
+               {
+                       fprintf (stderr, "Temporarily re-gaining privileges "
+                                       "failed: %s\n", strerror (errno));
+                       exit (EXIT_FAILURE);
+               }
+#endif
+
                while (fgets(line, sizeof(line), infile))
                {
                        /* Strip whitespace */
@@ -440,11 +1827,37 @@ int main (int argc, char **argv)
                                fprintf (stderr, "Adding host `%s' failed: %s\n", host, errmsg);
                                continue;
                        }
+                       else
+                       {
+                               host_num++;
+                       }
+               }
+
+#if _POSIX_SAVED_IDS
+               /* Drop privileges */
+               status = seteuid (getuid ());
+               if (status != 0)
+               {
+                       fprintf (stderr, "Temporarily dropping privileges "
+                                       "failed: %s\n", strerror (errno));
+                       exit (EXIT_FAILURE);
                }
+#endif
 
                fclose(infile);
        }
 
+#if _POSIX_SAVED_IDS
+       /* Regain privileges */
+       status = seteuid (saved_set_uid);
+       if (status != 0)
+       {
+               fprintf (stderr, "Temporarily re-gaining privileges "
+                               "failed: %s\n", strerror (errno));
+               exit (EXIT_FAILURE);
+       }
+#endif
+
        for (i = optind; i < argc; i++)
        {
                if (ping_host_add (ping, argv[i]) < 0)
@@ -454,37 +1867,29 @@ int main (int argc, char **argv)
                        fprintf (stderr, "Adding host `%s' failed: %s\n", argv[i], errmsg);
                        continue;
                }
+               else
+               {
+                       host_num++;
+               }
        }
 
-       /* Drop root privileges if we're setuid-root. */
-       setuid (getuid ());
-
-       i = 0;
-       for (iter = ping_iterator_get (ping);
-                       iter != NULL;
-                       iter = ping_iterator_next (iter))
+       /* Permanently drop root privileges if we're setuid-root. */
+       status = setuid (getuid ());
+       if (status != 0)
        {
-               ping_context_t *context;
-               size_t buffer_size;
-
-               context = context_create ();
-
-               buffer_size = sizeof (context->host);
-               ping_iterator_get_info (iter, PING_INFO_HOSTNAME, context->host, &buffer_size);
-
-               buffer_size = sizeof (context->addr);
-               ping_iterator_get_info (iter, PING_INFO_ADDRESS, context->addr, &buffer_size);
-
-               buffer_size = 0;
-               ping_iterator_get_info (iter, PING_INFO_DATA, NULL, &buffer_size);
+               fprintf (stderr, "Dropping privileges failed: %s\n",
+                               strerror (errno));
+               exit (EXIT_FAILURE);
+       }
 
-               printf ("PING %s (%s) %zu bytes of data.\n",
-                               context->host, context->addr, buffer_size);
+       if (host_num == 0)
+               exit (EXIT_FAILURE);
 
-               ping_iterator_set_context (iter, (void *) context);
+#if _POSIX_SAVED_IDS
+       saved_set_uid = (uid_t) -1;
+#endif
 
-               i++;
-       }
+       ping_initialize_contexts (ping);
 
        if (i == 0)
                return (1);
@@ -497,8 +1902,11 @@ int main (int argc, char **argv)
                return (1);
        }
 
+       pre_loop_hook (ping);
+
        while (opt_count != 0)
        {
+               int index;
                int status;
 
                if (gettimeofday (&tv_begin, NULL) < 0)
@@ -507,20 +1915,28 @@ int main (int argc, char **argv)
                        return (1);
                }
 
-               if (ping_send (ping) < 0)
+               status = ping_send (ping);
+               if (status == -EINTR)
+               {
+                       continue;
+               }
+               else if (status < 0)
                {
                        fprintf (stderr, "ping_send failed: %s\n",
                                        ping_get_error (ping));
                        return (1);
                }
 
+               index = 0;
                for (iter = ping_iterator_get (ping);
                                iter != NULL;
                                iter = ping_iterator_next (iter))
                {
-                       print_host (iter);
+                       update_host_hook (iter, index);
+                       index++;
                }
-               fflush (stdout);
+
+               pre_sleep_hook (ping);
 
                /* Don't sleep in the last iteration */
                if (opt_count == 1)
@@ -537,60 +1953,36 @@ int main (int argc, char **argv)
                /* printf ("Sleeping for %i.%09li seconds\n", (int) ts_wait.tv_sec, ts_wait.tv_nsec); */
                while ((status = nanosleep (&ts_wait, &ts_wait)) != 0)
                {
-                       if (errno != EINTR)
+                       if (errno == EINTR)
                        {
-                               perror ("nanosleep");
-                               break;
+                               continue;
                        }
-                       else if (opt_count == 0)
+                       else
                        {
-                               /* sigint */
+                               perror ("nanosleep");
                                break;
                        }
                }
 
+               post_sleep_hook (ping);
+
                if (opt_count > 0)
                        opt_count--;
        } /* while (opt_count != 0) */
 
-       for (iter = ping_iterator_get (ping);
-                       iter != NULL;
-                       iter = ping_iterator_next (iter))
-       {
-               ping_context_t *context;
-
-               context = ping_iterator_get_context (iter);
-
-               printf ("\n--- %s ping statistics ---\n"
-                               "%i packets transmitted, %i received, %.2f%% packet loss, time %.1fms\n",
-                               context->host, context->req_sent, context->req_rcvd,
-                               100.0 * (context->req_sent - context->req_rcvd) / ((double) context->req_sent),
-                               context->latency_total);
-
-               if (context->req_rcvd != 0)
-               {
-                       double num_total;
-                       double average;
-                       double deviation;
-
-                       num_total = (double) context->req_rcvd;
+       /* Returns the number of failed hosts according to -Z. */
+       status = post_loop_hook (ping);
 
-                       average = context->latency_total / num_total;
-                       deviation = sqrt (((num_total * context->latency_total_square) - (context->latency_total * context->latency_total))
-                                       / (num_total * (num_total - 1.0)));
-
-                       printf ("rtt min/avg/max/sdev = %.3f/%.3f/%.3f/%.3f ms\n",
-                                       context->latency_min,
-                                       average,
-                                       context->latency_max,
-                                       deviation);
-               }
+       ping_destroy (ping);
 
-               ping_iterator_set_context (iter, NULL);
-               context_destroy (context);
+       if (status == 0)
+               exit (EXIT_SUCCESS);
+       else
+       {
+               if (status > 255)
+                       status = 255;
+               exit (status);
        }
+} /* }}} int main */
 
-       ping_destroy (ping);
-
-       return (0);
-}
+/* vim: set fdm=marker : */