contrib/queryperf/queryperf.c

	queryperf.c revision a18fc12ba3d48b66bea298c80f3e3f09f3c91527
/*
 * Copyright (C) 2000, 2001  Nominum, Inc.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
 * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
 * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/***
 ***    DNS Query Performance Testing Tool  (queryperf.c)
 ***
 ***    Version $Id: queryperf.c,v 1.12 2007/09/05 07:36:04 marka Exp $
 ***
 ***    Stephen Jacob <sj@nominum.com>
 ***/

#define BIND_8_COMPAT   /* Pull in <arpa/nameser_compat.h> */

#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <time.h>
#include <unistd.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <math.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include "config.h"
#ifndef HAVE_GETADDRINFO
#include "missing/addrinfo.h"
#endif
#endif

/*
 * Configuration defaults
 */

#define DEF_MAX_QUERIES_OUTSTANDING 20
#define DEF_QUERY_TIMEOUT       5       /* in seconds */
#define DEF_SERVER_TO_QUERY     "127.0.0.1"
#define DEF_SERVER_PORT         "53"
#define DEF_BUFFER_SIZE         32      /* in k */

#define DEF_RTTARRAY_SIZE       50000
#define DEF_RTTARRAY_UNIT       100     /* in usec */

/*
 * Other constants / definitions
 */

#define COMMENT_CHAR            ';'
#define CONFIG_CHAR         '#'
#define MAX_PORT            65535
#define MAX_INPUT_LEN           512
#define MAX_DOMAIN_LEN          255
#define MAX_BUFFER_LEN          8192        /* in bytes */
#define HARD_TIMEOUT_EXTRA      5       /* in seconds */
#define RESPONSE_BLOCKING_WAIT_TIME 0.1     /* in seconds */
#define EDNSLEN             11
#define DNS_HEADERLEN           12

#define FALSE               0
#define TRUE                1

#define WHITESPACE          " \t\n"

enum directives_enum    { V_SERVER, V_PORT, V_MAXQUERIES, V_MAXWAIT };
#define DIRECTIVES  { "server", "port", "maxqueries", "maxwait" }
#define DIR_VALUES  { V_SERVER, V_PORT, V_MAXQUERIES, V_MAXWAIT }

#define QTYPE_STRINGS { \
    "A", "NS", "MD", "MF", "CNAME", "SOA", "MB", "MG", "MR", \
    "NULL", "WKS", "PTR", "HINFO", "MINFO", "MX", "TXT", "RP", \
    "AFSDB", "X25", "ISDN", "RT", "NSAP", "NSAP-PTR", "SIG", \
    "KEY", "PX", "GPOS", "AAAA", "LOC", "NXT", "EID", "NIMLOC", \
    "SRV", "ATMA", "NAPTR", "KX", "CERT", "A6", "DNAME", "SINK", \
    "OPT", "APL", "DS", "SSHFP", "IPSECKEY", "RRSIG", "NSEC", \
    "DNSKEY", "DHCID", "NSEC3", "NSEC3PARAM", "TLSA", "HIP", \
    "NINFO", "RKEY", "TALINK", "CDS", "SPF", "UINFO", "UID", \
    "GID", "UNSPEC", "NID", "L32", "L64", "LP", "TKEY", "TSIG", \
    "IXFR", "AXFR", "MAILB", "MAILA", "URI", "CAA", "*", "ANY", \
    "TA", "DLV" \
}

#define QTYPE_CODES { \
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, \
    19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, \
    34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, \
    49, 50, 51, 52, 55, 56, 57, 58, 59, 99, 100, 101, 102, 103, \
    104, 105, 106, 107, 249, 250, 251, 252, 253, 254, 255, 255, \
    256, 257, 32768, 32769 \
}

#define RCODE_STRINGS { \
    "NOERROR", "FORMERR", "SERVFAIL", "NXDOMAIN", \
    "NOTIMP", "REFUSED", "YXDOMAIN", "YXRRSET", \
    "NXRRSET", "NOTAUTH", "NOTZONE", "rcode11", \
    "rcode12", "rcode13", "rcode14", "rcode15" \
}

/*
 * Data type definitions
 */

#define QUERY_STATUS_MAGIC  0x51535441U /* QSTA */
#define VALID_QUERY_STATUS(q)   ((q) != NULL && \
                 (q)->magic == QUERY_STATUS_MAGIC)

struct query_status {
    unsigned int magic;
    int in_use;
    unsigned short int id;
    struct timeval sent_timestamp;
    char *desc;
    int qtype;
    char qname[MAX_DOMAIN_LEN + 1];
};

struct query_mininfo {      /* minimum info for timeout queries */
    int qtype;      /* use -1 if N/A */
    struct timeval sent_timestamp;
    char qname[MAX_DOMAIN_LEN + 1];
};

/*
 * Forward declarations.
 */
int is_uint(char *test_int, unsigned int *result);

/*
 * Configuration options (global)
 */

unsigned int max_queries_outstanding;           /* init 0 */
unsigned int query_timeout = DEF_QUERY_TIMEOUT;
int ignore_config_changes = FALSE;
unsigned int socket_bufsize = DEF_BUFFER_SIZE;

int family = AF_UNSPEC;
int use_stdin = TRUE;
char *datafile_name;                    /* init NULL */

char *server_to_query;                  /* init NULL */
char *server_port;                  /* init NULL */
struct addrinfo *server_ai;             /* init NULL */

int run_only_once = FALSE;
int use_timelimit = FALSE;
unsigned int run_timelimit;             /* init 0 */
unsigned int print_interval;                /* init 0 */

unsigned int target_qps;                /* init 0 */

int serverset = FALSE, portset = FALSE;
int queriesset = FALSE, timeoutset = FALSE;
int edns = FALSE, dnssec = FALSE;
int countrcodes = FALSE;
int rcodecounts[16] = {0};

int verbose = FALSE;
int recurse = 1;

/*
 * Other global stuff
 */

int setup_phase = TRUE;

FILE *datafile_ptr;                 /* init NULL */
unsigned int runs_through_file;             /* init 0 */

unsigned int num_queries_sent;              /* init 0 */
unsigned int num_queries_sent_interval;
unsigned int num_queries_outstanding;           /* init 0 */
unsigned int num_queries_timed_out;         /* init 0 */
unsigned int num_queries_possiblydelayed;       /* init 0 */
unsigned int num_queries_timed_out_interval;
unsigned int num_queries_possiblydelayed_interval;

struct timeval time_of_program_start;
struct timeval time_of_first_query;
double time_of_first_query_sec;
struct timeval time_of_first_query_interval;
struct timeval time_of_end_of_run;
struct timeval time_of_stop_sending;

struct timeval time_of_queryset_start;
double query_interval;
struct timeval time_of_next_queryset;

double rtt_max = -1;
double rtt_max_interval = -1;
double rtt_min = -1;
double rtt_min_interval = -1;
double rtt_total;
double rtt_total_interval;
int rttarray_size = DEF_RTTARRAY_SIZE;
int rttarray_unit = DEF_RTTARRAY_UNIT;
unsigned int *rttarray = NULL;
unsigned int *rttarray_interval = NULL;
unsigned int rtt_overflows;
unsigned int rtt_overflows_interval;
unsigned int rtt_counted;
unsigned int rtt_counted_interval;
char *rtt_histogram_file = NULL;

struct query_status *status;                /* init NULL */
unsigned int query_status_allocated;            /* init 0 */

int query_socket = -1;
int socket4 = -1, socket6 = -1;

static char *rcode_strings[] = RCODE_STRINGS;

static struct query_mininfo *timeout_queries;

/*
 * get_uint16:
 *   Get an unsigned short integer from a buffer (in network order)
 */
static unsigned short
get_uint16(unsigned char *buf) {
    unsigned short ret;

    ret = buf[0] * 256 + buf[1];

    return (ret);
}

/*
 * show_startup_info:
 *   Show name/version
 */
void
show_startup_info(void) {
    printf("\n"
"DNS Query Performance Testing Tool\n"
"Version: $Id: queryperf.c,v 1.12 2007/09/05 07:36:04 marka Exp $\n"
"\n");
}

/*
 * show_usage:
 *   Print out usage/syntax information
 */
void
show_usage(void) {
    fprintf(stderr,
"\n"
"Usage: queryperf [-d datafile] [-s server_addr] [-p port] [-q num_queries]\n"
"                 [-b bufsize] [-t timeout] [-n] [-l limit] [-f family] [-1]\n"
"                 [-i interval] [-r arraysize] [-u unit] [-H histfile]\n"
"                 [-T qps] [-e] [-D] [-R] [-c] [-v] [-h]\n"
"  -d specifies the input data file (default: stdin)\n"
"  -s sets the server to query (default: %s)\n"
"  -p sets the port on which to query the server (default: %s)\n"
"  -q specifies the maximum number of queries outstanding (default: %d)\n"
"  -t specifies the timeout for query completion in seconds (default: %d)\n"
"  -n causes configuration changes to be ignored\n"
"  -l specifies how a limit for how long to run tests in seconds (no default)\n"
"  -1 run through input only once (default: multiple iff limit given)\n"
"  -b set input/output buffer size in kilobytes (default: %d k)\n"
"  -i specifies interval of intermediate outputs in seconds (default: 0=none)\n"
"  -f specify address family of DNS transport, inet or inet6 (default: any)\n"
"  -r set RTT statistics array size (default: %d)\n"
"  -u set RTT statistics time unit in usec (default: %d)\n"
"  -H specifies RTT histogram data file (default: none)\n"
"  -T specify the target qps (default: 0=unspecified)\n"
"  -e enable EDNS 0\n"
"  -D set the DNSSEC OK bit (implies EDNS)\n"
"  -R disable recursion\n"
"  -c print the number of packets with each rcode\n"
"  -v verbose: report the RCODE of each response on stdout\n"
"  -h print this usage\n"
"\n",
            DEF_SERVER_TO_QUERY, DEF_SERVER_PORT,
            DEF_MAX_QUERIES_OUTSTANDING, DEF_QUERY_TIMEOUT,
        DEF_BUFFER_SIZE, DEF_RTTARRAY_SIZE, DEF_RTTARRAY_UNIT);
}

/*
 * set_datafile:
 *   Set the datafile to read
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
set_datafile(char *new_file) {
    char *dfname_tmp;

    if ((new_file == NULL) || (new_file[0] == '\0')) {
        fprintf(stderr, "Error: null datafile name\n");
        return (-1);
    }

    if ((dfname_tmp = malloc(strlen(new_file) + 1)) == NULL) {
        fprintf(stderr, "Error allocating memory for datafile name: "
                "%s\n", new_file);
        return (-1);
    }

    free(datafile_name);
    datafile_name = dfname_tmp;

    strcpy(datafile_name, new_file);
    use_stdin = FALSE;

    return (0);
}

/*
 * set_input_stdin:
 *   Set the input to be stdin (instead of a datafile)
 */
void
set_input_stdin(void) {
    use_stdin = TRUE;
    free(datafile_name);
    datafile_name = NULL;
}

/*
 * set_server:
 *   Set the server to be queried
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
set_server(char *new_name) {
    static struct hostent *server_he;

    /* If no change in server name, don't do anything... */
    if ((server_to_query != NULL) && (new_name != NULL))
        if (strcmp(new_name, server_to_query) == 0)
            return (0);

    if ((new_name == NULL) || (new_name[0] == '\0')) {
        fprintf(stderr, "Error: null server name\n");
        return (-1);
    }

    free(server_to_query);
    server_to_query = NULL;

    if ((server_to_query = malloc(strlen(new_name) + 1)) == NULL) {
        fprintf(stderr, "Error allocating memory for server name: "
                "%s\n", new_name);
        return (-1);
    }

    strcpy(server_to_query, new_name);

    return (0);
}

/*
 * set_server_port:
 *   Set the port on which to contact the server
 *
 *   Return -1 if port is invalid
 *   Return a non-negative integer otherwise
 */
int
set_server_port(char *new_port) {
    unsigned int uint_val;

    if ((is_uint(new_port, &uint_val)) != TRUE)
        return (-1);

    if (uint_val && uint_val > MAX_PORT)
        return (-1);
    else {
        if (server_port != NULL && new_port != NULL &&
            strcmp(server_port, new_port) == 0)
            return (0);

        free(server_port);
        server_port = NULL;

        if ((server_port = malloc(strlen(new_port) + 1)) == NULL) {
            fprintf(stderr,
                "Error allocating memory for server port: "
                "%s\n", new_port);
            return (-1);
        }

        strcpy(server_port, new_port);

        return (0);
    }
}

int
set_server_sa(void) {
    struct addrinfo hints, *res;
    static struct protoent *proto;
    int error;

    if (proto == NULL && (proto = getprotobyname("udp")) == NULL) {
        fprintf(stderr, "Error: getprotobyname call failed");
        return (-1);
    }

    memset(&hints, 0, sizeof(hints));
    hints.ai_family = family;
    hints.ai_socktype = SOCK_DGRAM;
    hints.ai_protocol = proto->p_proto;
    if ((error = getaddrinfo(server_to_query, server_port,
                 &hints, &res)) != 0) {
        fprintf(stderr, "Error: getaddrinfo(%s, %s) failed\n",
            server_to_query, server_port);
        return (-1);
    }

    /* replace the server's addrinfo */
    if (server_ai != NULL)
        freeaddrinfo(server_ai);
    server_ai = res;
    return (0);
}

/*
 * is_digit:
 *   Tests if a character is a digit
 *
 *   Return TRUE if it is
 *   Return FALSE if it is not
 */
int
is_digit(char d) {
    if (d < '0' || d > '9')
        return (FALSE);
    else
        return (TRUE);
}

/*
 * is_uint:
 *   Tests if a string, test_int, is a valid unsigned integer
 *
 *   Sets *result to be the unsigned integer if it is valid
 *
 *   Return TRUE if it is
 *   Return FALSE if it is not
 */
int
is_uint(char *test_int, unsigned int *result) {
    unsigned long int value;
    char *end;

    if (test_int == NULL)
        return (FALSE);

    if (is_digit(test_int[0]) == FALSE)
        return (FALSE);

    value = strtoul(test_int, &end, 10);

    if ((errno == ERANGE) || (*end != '\0') || (value > UINT_MAX))
        return (FALSE);

    *result = (unsigned int)value;
    return (TRUE);
}

/*
 * set_max_queries:
 *   Set the maximum number of outstanding queries
 *
 *   Returns -1 on failure
 *   Returns a non-negative integer otherwise
 */
int
set_max_queries(unsigned int new_max) {
    static unsigned int size_qs = sizeof(struct query_status);
    struct query_status *temp_stat;
    unsigned int count;

    if (new_max > query_status_allocated) {
        temp_stat = realloc(status, new_max * size_qs);

        if (temp_stat == NULL) {
            fprintf(stderr, "Error resizing query_status\n");
            return (-1);
        } else {
            status = temp_stat;

            /*
             * Be careful to only initialise between above
             * the previously allocated space. Note that the
             * allocation may be larger than the current
             * max_queries_outstanding. We don't want to
             * "forget" any outstanding queries! We might
             * still have some above the bounds of the max.
             */
            count = query_status_allocated;
            for (; count < new_max; count++) {
                status[count].in_use = FALSE;
                status[count].magic = QUERY_STATUS_MAGIC;
                status[count].desc = NULL;
            }

            query_status_allocated = new_max;
        }
    }

    max_queries_outstanding = new_max;

    return (0);
}

/*
 * parse_args:
 *   Parse program arguments and set configuration options
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
parse_args(int argc, char **argv) {
    int c;
    unsigned int uint_arg_val;

    while ((c = getopt(argc, argv,
               "f:q:t:i:nd:s:p:1l:b:eDcvr:RT:u:H:h")) != -1) {
        switch (c) {
        case 'f':
            if (strcmp(optarg, "inet") == 0)
                family = AF_INET;
#ifdef AF_INET6
            else if (strcmp(optarg, "inet6") == 0)
                family = AF_INET6;
#endif
            else if (strcmp(optarg, "any") == 0)
                family = AF_UNSPEC;
            else {
                fprintf(stderr, "Invalid address family: %s\n",
                    optarg);
                return (-1);
            }
            break;
        case 'q':
            if (is_uint(optarg, &uint_arg_val) == TRUE) {
                set_max_queries(uint_arg_val);
                queriesset = TRUE;
            } else {
                fprintf(stderr, "Option requires a positive "
                        "integer value: -%c %s\n",
                    c, optarg);
                return (-1);
            }
            break;

        case 't':
            if (is_uint(optarg, &uint_arg_val) == TRUE) {
                query_timeout = uint_arg_val;
                timeoutset = TRUE;
            } else {
                fprintf(stderr, "Option requires a positive "
                        "integer value: -%c %s\n",
                        c, optarg);
                return (-1);
            }
            break;

        case 'n':
            ignore_config_changes = TRUE;
            break;

        case 'd':
            if (set_datafile(optarg) == -1) {
                fprintf(stderr, "Error setting datafile "
                    "name: %s\n", optarg);
                return (-1);
            }
            break;

        case 's':
            if (set_server(optarg) == -1) {
                fprintf(stderr, "Error setting server "
                    "name: %s\n", optarg);
                return (-1);
            }
            serverset = TRUE;
            break;

        case 'p':
            if (is_uint(optarg, &uint_arg_val) == TRUE &&
                uint_arg_val < MAX_PORT)
            {
                set_server_port(optarg);
                portset = TRUE;
            } else {
                fprintf(stderr, "Option requires a positive "
                        "integer between 0 and %d: -%c %s\n",
                    MAX_PORT - 1, c, optarg);
                return (-1);
            }
            break;

        case '1':
            run_only_once = TRUE;
            break;

        case 'l':
            if (is_uint(optarg, &uint_arg_val) == TRUE) {
                use_timelimit = TRUE;
                run_timelimit = uint_arg_val;
            } else {
                fprintf(stderr, "Option requires a positive "
                        "integer: -%c %s\n",
                    c, optarg);
                return (-1);
            }
            break;

        case 'b':
            if (is_uint(optarg, &uint_arg_val) == TRUE) {
                socket_bufsize = uint_arg_val;
            } else {
                fprintf(stderr, "Option requires a positive "
                    "integer: -%c %s\n",
                    c, optarg);
                return (-1);
            }
            break;
        case 'e':
            edns = TRUE;
            break;
        case 'D':
            dnssec = TRUE;
            edns = TRUE;
            break;
        case 'c':
            countrcodes = TRUE;
            break;
        case 'v':
            verbose = 1;
            break;
        case 'i':
            if (is_uint(optarg, &uint_arg_val) == TRUE)
                print_interval = uint_arg_val;
            else {
                fprintf(stderr, "Invalid interval: %s\n",
                    optarg);
                return (-1);
            }
            break;
        case 'R':
            recurse = 0;
            break;
        case 'r':
            if (is_uint(optarg, &uint_arg_val) == TRUE)
                rttarray_size = uint_arg_val;
            else {
                fprintf(stderr, "Invalid RTT array size: %s\n",
                    optarg);
                return (-1);
            }
            break;
        case 'u':
            if (is_uint(optarg, &uint_arg_val) == TRUE)
                rttarray_unit = uint_arg_val;
            else {
                fprintf(stderr, "Invalid RTT unit: %s\n",
                    optarg);
                return (-1);
            }
            break;
        case 'H':
            rtt_histogram_file = optarg;
            break;
        case 'T':
            if (is_uint(optarg, &uint_arg_val) == TRUE)
                target_qps = uint_arg_val;
            else {
                fprintf(stderr, "Invalid target qps: %s\n",
                    optarg);
                return (-1);
            }
            break;
        case 'h':
            return (-1);
        default:
            fprintf(stderr, "Invalid option: -%c\n", optopt);
            return (-1);
        }
    }

    if (run_only_once == FALSE && use_timelimit == FALSE)
        run_only_once = TRUE;

    return (0);
}

/*
 * open_datafile:
 *   Open the data file ready for reading
 *
 *   Return -1 on failure
 *   Return non-negative integer on success
 */
int
open_datafile(void) {
    if (use_stdin == TRUE) {
        datafile_ptr = stdin;
        return (0);
    } else {
        if ((datafile_ptr = fopen(datafile_name, "r")) == NULL) {
            fprintf(stderr, "Error: unable to open datafile: %s\n",
                    datafile_name);
            return (-1);
        } else
            return (0);
    }
}

/*
 * close_datafile:
 *   Close the data file if any is open
 *
 *   Return -1 on failure
 *   Return non-negative integer on success, including if not needed
 */
int
close_datafile(void) {
    if ((use_stdin == FALSE) && (datafile_ptr != NULL)) {
        if (fclose(datafile_ptr) != 0) {
            fprintf(stderr, "Error: unable to close datafile\n");
            return (-1);
        }
    }

    return (0);
}

/*
 * open_socket:
 *   Open a socket for the queries.  When we have an active socket already,
 *   close it and open a new one.
 *
 *   Return -1 on failure
 *   Return the socket identifier
 */
int
open_socket(void) {
    int sock;
    int ret;
    int bufsize;
    struct addrinfo hints, *res;

    memset(&hints, 0, sizeof(hints));
    hints.ai_family = server_ai->ai_family;
    hints.ai_socktype = server_ai->ai_socktype;
    hints.ai_protocol = server_ai->ai_protocol;
    hints.ai_flags = AI_PASSIVE;

    if ((ret = getaddrinfo(NULL, "0", &hints, &res)) != 0) {
        fprintf(stderr,
            "Error: getaddrinfo for bind socket failed: %s\n",
            gai_strerror(ret));
        return (-1);
    }

    if ((sock = socket(res->ai_family, SOCK_DGRAM,
               res->ai_protocol)) == -1) {
        fprintf(stderr, "Error: socket call failed");
        goto fail;
    }

#if defined(AF_INET6) && defined(IPV6_V6ONLY)
    if (res->ai_family == AF_INET6) {
        int on = 1;

        if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
                   &on, sizeof(on)) == -1) {
            fprintf(stderr,
                "Warning: setsockopt(IPV6_V6ONLY) failed\n");
        }
    }
#endif

    if (bind(sock, res->ai_addr, res->ai_addrlen) == -1)
        fprintf(stderr, "Error: bind call failed");

    freeaddrinfo(res);

    bufsize = 1024 * socket_bufsize;

    ret = setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
             (char *) &bufsize, sizeof(bufsize));
    if (ret < 0)
        fprintf(stderr, "Warning:  setsockbuf(SO_RCVBUF) failed\n");

    ret = setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
             (char *) &bufsize, sizeof(bufsize));
    if (ret < 0)
        fprintf(stderr, "Warning:  setsockbuf(SO_SNDBUF) failed\n");

    return (sock);

 fail:
    if (res)
        freeaddrinfo(res);
    return (-1);
}

/*
 * close_socket:
 *   Close the query socket(s)
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
close_socket(void) {
    if (socket4 != -1) {
        if (close(socket4) != 0) {
            fprintf(stderr,
                "Error: unable to close IPv4 socket\n");
            return (-1);
        }
    }

    if (socket6 != -1) {
        if (close(socket6) != 0) {
            fprintf(stderr,
                "Error: unable to close IPv6 socket\n");
            return (-1);
        }
    }

    query_socket = -1;

    return (0);
}

/*
 * change_socket:
 *   Choose an appropriate socket according to the address family of the
 *   current server.  Open a new socket if necessary.
 *
 *   Return -1 on failure
 *   Return the socket identifier
 */
int
change_socket(void) {
    int s, *sockp;

    switch (server_ai->ai_family) {
    case AF_INET:
        sockp = &socket4;
        break;
#ifdef AF_INET6
    case AF_INET6:
        sockp = &socket6;
        break;
#endif
    default:
        fprintf(stderr, "unexpected address family: %d\n",
            server_ai->ai_family);
        exit(1);
    }

    if (*sockp == -1) {
        if ((s = open_socket()) == -1)
            return (-1);
        *sockp = s;
    }

    return (*sockp);
}

/*
 * reset_rttarray:
 *   (re)allocate RTT array and zero-clear the whole buffer.
 *   if array is being used, it is freed.
 *   Returns -1 on failure
 *   Returns a non-negative integer otherwise
 */
int
reset_rttarray(int size) {
    if (rttarray != NULL)
        free(rttarray);
    if (rttarray_interval != NULL)
        free(rttarray_interval);

    rttarray = NULL;
    rttarray_interval = NULL;
    rtt_max = -1;
    rtt_min = -1;

    if (size > 0) {
        rttarray = malloc(size * sizeof(rttarray[0]));
        if (rttarray == NULL) {
            fprintf(stderr,
                "Error: allocating memory for RTT array\n");
            return (-1);
        }
        memset(rttarray, 0, size * sizeof(rttarray[0]));

        rttarray_interval = malloc(size *
                       sizeof(rttarray_interval[0]));
        if (rttarray_interval == NULL) {
            fprintf(stderr,
                "Error: allocating memory for RTT array\n");
            return (-1);
        }

        memset(rttarray_interval, 0,
               size * sizeof(rttarray_interval[0]));
    }

    return (0);
}

/*
 * set_query_interval:
 *   set the interval of consecutive queries if the target qps are specified.
 *   Returns -1 on failure
 *   Returns a non-negative integer otherwise
 */
int
set_query_interval(unsigned int qps) {
    if (qps == 0)
        return (0);

    query_interval = (1.0 / (double)qps);

    return (0);
}

/*
 * setup:
 *   Set configuration options from command line arguments
 *   Open datafile ready for reading
 *
 *   Return -1 on failure
 *   Return non-negative integer on success
 */
int
setup(int argc, char **argv) {
    set_input_stdin();

    if (set_max_queries(DEF_MAX_QUERIES_OUTSTANDING) == -1) {
        fprintf(stderr, "%s: Unable to set default max outstanding "
                "queries\n", argv[0]);
        return (-1);
    }

    if (set_server(DEF_SERVER_TO_QUERY) == -1) {
        fprintf(stderr, "%s: Error setting default server name\n",
                argv[0]);
        return (-1);
    }

    if (set_server_port(DEF_SERVER_PORT) == -1) {
        fprintf(stderr, "%s: Error setting default server port\n",
                argv[0]);
        return (-1);
    }

    if (parse_args(argc, argv) == -1) {
        show_usage();
        return (-1);
    }

    if (open_datafile() == -1)
        return (-1);

    if (set_server_sa() == -1)
        return (-1);

    if ((query_socket = change_socket()) == -1)
        return (-1);

    if (reset_rttarray(rttarray_size) == -1)
        return (-1);

    if (set_query_interval(target_qps) == -1)
        return (-1);

    return (0);
}

/*
 * set_timenow:
 *   Set a timeval struct to indicate the current time
 */
void
set_timenow(struct timeval *tv) {
    if (gettimeofday(tv, NULL) == -1) {
        fprintf(stderr, "Error in gettimeofday(). Using inaccurate "
                "time() instead\n");
        tv->tv_sec = time(NULL);
        tv->tv_usec = 0;
    }
}

/*
 * addtv:
 *   add tv1 and tv2, store the result in tv_result.
 */
void
addtv(struct timeval *tv1, struct timeval *tv2, struct timeval *tv_result) {
    tv_result->tv_sec = tv1->tv_sec + tv2->tv_sec;
    tv_result->tv_usec = tv1->tv_usec + tv2->tv_usec;
    if (tv_result->tv_usec > 1000000) {
        tv_result->tv_sec++;
        tv_result->tv_usec -= 1000000;
    }
}

/*
 * difftv:
 *   Find the difference in seconds between two timeval structs.
 *
 *   Return the difference between tv1 and tv2 in seconds in a double.
 */
double
difftv(struct timeval tv1, struct timeval tv2) {
    long diff_sec, diff_usec;
    double diff;

    diff_sec = tv1.tv_sec - tv2.tv_sec;
    diff_usec = tv1.tv_usec - tv2.tv_usec;

    diff = (double)diff_sec + ((double)diff_usec / 1000000.0);

    return (diff);
}

/*
 * timelimit_reached:
 *   Have we reached the time limit (if any)?
 *
 *   Returns FALSE if there is no time limit or if we have not reached it
 *   Returns TRUE otherwise
 */
int
timelimit_reached(void) {
    struct timeval time_now;

    set_timenow(&time_now);

    if (use_timelimit == FALSE)
        return (FALSE);

    if (setup_phase == TRUE) {
        if (difftv(time_now, time_of_program_start)
            < (double)(run_timelimit + HARD_TIMEOUT_EXTRA))
            return (FALSE);
        else
            return (TRUE);
    } else {
        if (difftv(time_now, time_of_first_query)
            < (double)run_timelimit)
            return (FALSE);
        else
            return (TRUE);
    }
}

/*
 * keep_sending:
 *   Should we keep sending queries or stop here?
 *
 *   Return TRUE if we should keep on sending queries
 *   Return FALSE if we should stop
 *
 *   Side effects:
 *   Rewinds the input and clears reached_end_input if we have reached the
 *   end of the input, but we are meant to run through it multiple times
 *   and have not hit the time limit yet (if any is set).
 */
int
keep_sending(int *reached_end_input) {
    static int stop = FALSE;

    if (stop == TRUE)
        return (FALSE);

    if ((*reached_end_input == FALSE) && (timelimit_reached() == FALSE))
        return (TRUE);
    else if ((*reached_end_input == TRUE) && (run_only_once == FALSE)
             && (timelimit_reached() == FALSE)) {
        rewind(datafile_ptr);
        *reached_end_input = FALSE;
        runs_through_file++;
        return (TRUE);
    } else {
        if (*reached_end_input == TRUE)
            runs_through_file++;
        set_timenow(&time_of_stop_sending);
        stop = TRUE;
        return (FALSE);
    }
}

/*
 * queries_outstanding:
 *   How many queries are outstanding?
 *
 *   Returns the number of outstanding queries
 */
unsigned int
queries_outstanding(void) {
    return (num_queries_outstanding);
}

/*
 * next_input_line:
 *   Get the next non-comment line from the input file
 *
 *   Put text in line, up to max of n chars. Skip comment lines.
 *   Skip empty lines.
 *
 *   Return line length on success
 *   Return 0 if cannot read a non-comment line (EOF or error)
 */
int
next_input_line(char *line, int n) {
    char *result;

    do {
        result = fgets(line, n, datafile_ptr);
    } while ((result != NULL) &&
             ((line[0] == COMMENT_CHAR) || (line[0] == '\n')));

    if (result == NULL)
        return (0);
    else
        return (strlen(line));
}

/*
 * identify_directive:
 *   Gives us a numerical value equivelant for a directive string
 *
 *   Returns the value for the directive
 *   Returns -1 if not a valid directive
 */
int
identify_directive(char *dir) {
    static char *directives[] = DIRECTIVES;
    static int dir_values[] = DIR_VALUES;
    unsigned int index, num_directives;

    num_directives = sizeof(directives) / sizeof(directives[0]);

    if (num_directives > (sizeof(dir_values) / sizeof(int)))
        num_directives = sizeof(dir_values) / sizeof(int);

    for (index = 0; index < num_directives; index++) {
        if (strcmp(dir, directives[index]) == 0)
            return (dir_values[index]);
    }

    return (-1);
}

/*
 * update_config:
 *   Update configuration options from a line from the input file
 */
void
update_config(char *config_change_desc) {
    char *directive, *config_value, *trailing_garbage;
    char conf_copy[MAX_INPUT_LEN + 1];
    unsigned int uint_val;
    int directive_number;
    int check;
    int old_af;

    if (ignore_config_changes == TRUE) {
        fprintf(stderr, "Ignoring configuration change: %s",
                config_change_desc);
        return;
    }

    strcpy(conf_copy, config_change_desc);

    ++config_change_desc;

    if (*config_change_desc == '\0') {
        fprintf(stderr, "Invalid config: No directive present: %s\n",
                conf_copy);
        return;
    }

    if (index(WHITESPACE, *config_change_desc) != NULL) {
        fprintf(stderr, "Invalid config: Space before directive or "
                "no directive present: %s\n", conf_copy);
        return;
    }

    directive = strtok(config_change_desc, WHITESPACE);
    config_value = strtok(NULL, WHITESPACE);
    trailing_garbage = strtok(NULL, WHITESPACE);

    if ((directive_number = identify_directive(directive)) == -1) {
        fprintf(stderr, "Invalid config: Bad directive: %s\n",
                conf_copy);
        return;
    }

    if (config_value == NULL) {
        fprintf(stderr, "Invalid config: No value present: %s\n",
                conf_copy);
        return;
    }

    if (trailing_garbage != NULL) {
        fprintf(stderr, "Config warning: "
                "trailing garbage: %s\n", conf_copy);
    }

    switch(directive_number) {

    case V_SERVER:
        if (serverset && (setup_phase == TRUE)) {
            fprintf(stderr, "Config change overridden by command "
                    "line: %s\n", directive);
            return;
        }

        if (set_server(config_value) == -1) {
            fprintf(stderr, "Set server error: unable to change "
                    "the server name to '%s'\n", config_value);
            return;
        }

        old_af = server_ai->ai_family;
        if (set_server_sa() == -1) {
            fprintf(stderr, "Set server error: unable to resolve "
                "a new server '%s'\n",
                config_value);
            return;
        }
        if (old_af != server_ai->ai_family) {
            if ((query_socket = change_socket()) == -1) {
                /* XXX: this is fatal */
                fprintf(stderr, "Set server error: "
                    "unable to open a new socket "
                    "for '%s'\n", config_value);
                exit(1);
            }
        }

        break;

    case V_PORT:
        if (portset && (setup_phase == TRUE)) {
            fprintf(stderr, "Config change overridden by command "
                    "line: %s\n", directive);
            return;
        }

        check = is_uint(config_value, &uint_val);

        if ((check == TRUE) && (uint_val > 0)) {
            if (set_server_port(config_value) == -1) {
                fprintf(stderr, "Invalid config: Bad value for"
                        " %s: %s\n", directive, config_value);
            } else {
                if (set_server_sa() == -1) {
                    fprintf(stderr,
                        "Failed to set a new port\n");
                    return;
                }
            }
        } else
            fprintf(stderr, "Invalid config: Bad value for "
                    "%s: %s\n", directive, config_value);
        break;

    case V_MAXQUERIES:
        if (queriesset && (setup_phase == TRUE)) {
            fprintf(stderr, "Config change overridden by command "
                    "line: %s\n", directive);
            return;
        }

        check = is_uint(config_value, &uint_val);

        if ((check == TRUE) && (uint_val > 0)) {
            set_max_queries(uint_val);
        } else
            fprintf(stderr, "Invalid config: Bad value for "
                    "%s: %s\n", directive, config_value);
        break;

    case V_MAXWAIT:
        if (timeoutset && (setup_phase == TRUE)) {
            fprintf(stderr, "Config change overridden by command "
                    "line: %s\n", directive);
            return;
        }

        check = is_uint(config_value, &uint_val);

        if ((check == TRUE) && (uint_val > 0)) {
            query_timeout = uint_val;
        } else
            fprintf(stderr, "Invalid config: Bad value for "
                    "%s: %s\n", directive, config_value);
        break;

    default:
        fprintf(stderr, "Invalid config: Bad directive: %s\n",
                directive);
        break;
    }
}

/*
 * parse_query:
 *   Parse a query line from the input file
 *
 *   Set qname to be the domain to query (up to a max of qnlen chars)
 *   Set qtype to be the type of the query
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
parse_query(char *input, char *qname, unsigned int qnlen, int *qtype) {
    static char *qtype_strings[] = QTYPE_STRINGS;
    static int qtype_codes[] = QTYPE_CODES;
    unsigned int num_types, index;
    int found = FALSE;
    char incopy[MAX_INPUT_LEN + 1];
    char *domain_str, *type_str;

    num_types = sizeof(qtype_strings) / sizeof(qtype_strings[0]);
    if (num_types > (sizeof(qtype_codes) / sizeof(int)))
        num_types = sizeof(qtype_codes) / sizeof(int);

    strcpy(incopy, input);

    domain_str = strtok(incopy, WHITESPACE);
    type_str = strtok(NULL, WHITESPACE);

    if ((domain_str == NULL) || (type_str == NULL)) {
        fprintf(stderr, "Invalid query input format: %s\n", input);
        return (-1);
    }

    if (strlen(domain_str) > qnlen) {
        fprintf(stderr, "Query domain too long: %s\n", domain_str);
        return (-1);
    }

    for (index = 0; (index < num_types) && (found == FALSE); index++) {
        if (strcasecmp(type_str, qtype_strings[index]) == 0) {
            *qtype = qtype_codes[index];
            found = TRUE;
        }
    }

    if (found == FALSE) {
        fprintf(stderr, "Query type not understood: %s\n", type_str);
        return (-1);
    }

    strcpy(qname, domain_str);

    return (0);
}

/*
 * dispatch_query:
 *   Send the query packet for the entry
 *
 *   Return -1 on failure
 *   Return a non-negative integer otherwise
 */
int
dispatch_query(unsigned short int id, char *dom, int qt, u_char **pktp,
           int *pktlenp)
{
    static u_char packet_buffer[PACKETSZ + 1];
    int buffer_len = PACKETSZ;
    int bytes_sent;
    unsigned short int net_id = htons(id);
    char *id_ptr = (char *)&net_id;
    HEADER *hp = (HEADER *)packet_buffer;

    buffer_len = res_mkquery(QUERY, dom, C_IN, qt, NULL, 0,
                 NULL, packet_buffer, PACKETSZ);
    if (buffer_len == -1) {
        fprintf(stderr, "Failed to create query packet: %s %d\n",
                dom, qt);
        return (-1);
    }
    hp->rd = recurse;
    if (edns) {
        unsigned char *p;
        if (buffer_len + EDNSLEN >= PACKETSZ) {
            fprintf(stderr, "Failed to add OPT to query packet\n");
            return (-1);
        }
        packet_buffer[11] = 1;
        p = &packet_buffer[buffer_len];
        *p++ = 0;   /* root name */
        *p++ = 0;
        *p++ = 41;  /* OPT */
        *p++ = 16;
        *p++ = 0;   /* UDP payload size (4K) */
        *p++ = 0;   /* extended rcode */
        *p++ = 0;   /* version */
        if (dnssec)
            *p++ = 0x80;    /* upper flag bits - DO set */
        else
            *p++ = 0;   /* upper flag bits */
        *p++ = 0;   /* lower flag bit */
        *p++ = 0;
        *p++ = 0;   /* rdlen == 0 */
        buffer_len += EDNSLEN;
    }

    packet_buffer[0] = id_ptr[0];
    packet_buffer[1] = id_ptr[1];

    bytes_sent = sendto(query_socket, packet_buffer, buffer_len, 0,
                server_ai->ai_addr, server_ai->ai_addrlen);
    if (bytes_sent == -1) {
        fprintf(stderr, "Failed to send query packet: %s %d\n",
                dom, qt);
        return (-1);
    }

    if (bytes_sent != buffer_len)
        fprintf(stderr, "Warning: incomplete packet sent: %s %d\n",
                dom, qt);

    *pktp = packet_buffer;
    *pktlenp = buffer_len;

    return (0);
}

/*
 * send_query:
 *   Send a query based on a line of input
 */
void
send_query(char *query_desc) {
    static unsigned short int use_query_id = 0;
    static int qname_len = MAX_DOMAIN_LEN;
    static char domain[MAX_DOMAIN_LEN + 1];
    u_char *qpkt;
    char serveraddr[NI_MAXHOST];
    int query_type, qpkt_len;
    unsigned int count;

    use_query_id++;

    if (parse_query(query_desc, domain, qname_len, &query_type) == -1) {
        fprintf(stderr, "Error parsing query: %s\n", query_desc);
        return;
    }

    if (dispatch_query(use_query_id, domain, query_type,
               &qpkt, &qpkt_len) == -1) {
        char *addrstr;

        if (getnameinfo(server_ai->ai_addr, server_ai->ai_addrlen,
                serveraddr, sizeof(serveraddr), NULL, 0,
                NI_NUMERICHOST) == 0) {
            addrstr = serveraddr;
        } else
            addrstr = "???"; /* XXX: this should not happen */
        fprintf(stderr, "Error sending query to %s: %s\n",
            addrstr, query_desc);
        return;
    }

    if (setup_phase == TRUE) {
        set_timenow(&time_of_first_query);
        time_of_first_query_sec = (double)time_of_first_query.tv_sec +
            ((double)time_of_first_query.tv_usec / 1000000.0);
        setup_phase = FALSE;
        if (getnameinfo(server_ai->ai_addr, server_ai->ai_addrlen,
                serveraddr, sizeof(serveraddr), NULL, 0,
                NI_NUMERICHOST) != 0) {
            fprintf(stderr, "Error printing server address\n");
            return;
        }
        printf("[Status] Sending queries (beginning with %s)\n",
               serveraddr);
    }

    /* Find the first slot in status[] that is not in use */
    for (count = 0; (status[count].in_use == TRUE)
         && (count < max_queries_outstanding); count++);

    if (status[count].in_use == TRUE) {
        fprintf(stderr, "Unexpected error: We have run out of "
            "status[] space!\n");
        return;
    }

    /* Register the query in status[] */
    status[count].id = use_query_id;
    if (verbose)
        status[count].desc = strdup(query_desc);
    set_timenow(&status[count].sent_timestamp);
    status[count].qtype = query_type;
    if (dn_expand(qpkt, qpkt + qpkt_len, qpkt + DNS_HEADERLEN,
              status[count].qname, MAX_DOMAIN_LEN) == -1) {
        fprintf(stderr, "Unexpected error: "
            "query message doesn't have qname?\n");
        return;
    }
    status[count].in_use = TRUE;

    if (num_queries_sent_interval == 0)
        set_timenow(&time_of_first_query_interval);

    num_queries_sent++;
    num_queries_sent_interval++;
    num_queries_outstanding++;
}

void
register_rtt(struct timeval *timestamp, char *qname, int qtype,
         unsigned int rcode)
{
    int i;
    int oldquery = FALSE;
    struct timeval now;
    double rtt;

    set_timenow(&now);
    rtt = difftv(now, *timestamp);

    if (difftv(*timestamp, time_of_first_query_interval) < 0)
        oldquery = TRUE;

    if (rtt_max < 0 || rtt_max < rtt)
        rtt_max = rtt;

    if (rtt_min < 0 || rtt_min > rtt)
        rtt_min = rtt;

    rtt_total += rtt;
    rtt_counted++;

    if (!oldquery) {
        if (rtt_max_interval < 0 || rtt_max_interval < rtt)
            rtt_max_interval = rtt;

        if (rtt_min_interval < 0 || rtt_min_interval > rtt)
            rtt_min_interval = rtt;

        rtt_total_interval += rtt;
        rtt_counted_interval++;
    }

    if (rttarray == NULL)
        return;

    i = (int)(rtt * (1000000.0 / rttarray_unit));
    if (i < rttarray_size) {
        rttarray[i]++;
        if (!oldquery)
            rttarray_interval[i]++;
    } else {
        fprintf(stderr, "Warning: RTT is out of range: %.6lf "
            "[query=%s/%d, rcode=%u]\n", rtt, qname, qtype, rcode);
        rtt_overflows++;
        if (!oldquery)
            rtt_overflows_interval++;
    }
}

/*
 * register_response:
 *   Register receipt of a query
 *
 *   Removes (sets in_use = FALSE) the record for the given query id in
 *   status[] if any exists.
 */
void
register_response(unsigned short int id, unsigned int rcode, char *qname,
    int qtype)
{
    unsigned int ct = 0;
    int found = FALSE;
    struct timeval now;
    double rtt;

    if (timeout_queries != NULL) {
        struct query_mininfo *qi = &timeout_queries[id];

        if (qi->qtype == qtype && strcasecmp(qi->qname, qname) == 0) {
            register_rtt(&qi->sent_timestamp, qname, qtype, rcode);
            qi->qtype = -1;
            found = TRUE;
        }
    }

    for (; (ct < query_status_allocated) && (found == FALSE); ct++) {
        if (status[ct].in_use == TRUE && status[ct].id == id &&
            status[ct].qtype == qtype &&
            strcasecmp(status[ct].qname, qname) == 0) {
            status[ct].in_use = FALSE;
            num_queries_outstanding--;
            found = TRUE;

            register_rtt(&status[ct].sent_timestamp, qname, qtype,
                     rcode);

            if (status[ct].desc) {
                printf("> %s %s\n", rcode_strings[rcode],
                       status[ct].desc);
                free(status[ct].desc);
            }
        }
    }

    if (countrcodes && (found == TRUE || target_qps > 0))
        rcodecounts[rcode]++;

    if (found == FALSE) {
        if (target_qps > 0) {
            num_queries_possiblydelayed++;
            num_queries_possiblydelayed_interval++;
        } else {
            fprintf(stderr,
                "Warning: Received a response with an "
                "unexpected (maybe timed out) id: %u\n", id);
        }
    }
}

/*
 * process_single_response:
 *   Receive from the given socket & process an invididual response packet.
 *   Remove it from the list of open queries (status[]) and decrement the
 *   number of outstanding queries if it matches an open query.
 */
void
process_single_response(int sockfd) {
    struct sockaddr_storage from_addr_ss;
    struct sockaddr *from_addr;
    static unsigned char in_buf[MAX_BUFFER_LEN];
    char qname[MAX_DOMAIN_LEN + 1];
    int numbytes, addr_len, resp_id, qnamelen;
    int qtype, flags;

    memset(&from_addr_ss, 0, sizeof(from_addr_ss));
    from_addr = (struct sockaddr *)&from_addr_ss;
    addr_len = sizeof(from_addr_ss);

    if ((numbytes = recvfrom(sockfd, in_buf, MAX_BUFFER_LEN,
         0, from_addr, &addr_len)) == -1) {
        fprintf(stderr, "Error receiving datagram\n");
        return;
    }

    if (numbytes < DNS_HEADERLEN) {
        if (verbose)
            fprintf(stderr, "Malformed response\n");
        return;
    }
    resp_id = get_uint16(in_buf);
    flags = get_uint16(in_buf + 2);
    qnamelen = dn_expand(in_buf, in_buf + numbytes, in_buf + DNS_HEADERLEN,
                 qname, MAX_DOMAIN_LEN);
    if (qnamelen == -1) {
        if (verbose)
            fprintf(stderr,
                "Failed to retrieve qname from response\n");
        return;
    }
    if (numbytes < DNS_HEADERLEN + qnamelen + 2) {
        if (verbose)
            fprintf(stderr, "Malformed response\n");
        return;
    }
    qtype = get_uint16(in_buf + DNS_HEADERLEN + qnamelen);

    register_response(resp_id, flags & 0xF, qname, qtype);
}

/*
 * data_available:
 *   Is there data available on the given file descriptor?
 *
 *   Return TRUE if there is
 *   Return FALSE otherwise
 */
int
data_available(double wait) {
    fd_set read_fds;
    struct timeval tv;
    int retval;
    int available = FALSE;
    int maxfd = -1;

    /* Set list of file descriptors */
    FD_ZERO(&read_fds);
    if (socket4 != -1) {
        FD_SET(socket4, &read_fds);
        maxfd = socket4;
    }
    if (socket6 != -1) {
        FD_SET(socket6, &read_fds);
        if (maxfd == -1 || maxfd < socket6)
            maxfd = socket6;
    }

    if ((wait > 0.0) && (wait < (double)LONG_MAX)) {
        tv.tv_sec = (long)floor(wait);
        tv.tv_usec = (long)(1000000.0 * (wait - floor(wait)));
    } else {
        tv.tv_sec = 0;
        tv.tv_usec = 0;
    }

    retval = select(maxfd + 1, &read_fds, NULL, NULL, &tv);

    if (socket4 != -1 && FD_ISSET(socket4, &read_fds)) {
        available = TRUE;
        process_single_response(socket4);
    }
    if (socket6 != -1 && FD_ISSET(socket6, &read_fds)) {
        available = TRUE;
        process_single_response(socket6);
    }

    return (available);
}

/*
 * process_responses:
 *   Go through any/all received responses and remove them from the list of
 *   open queries (set in_use = FALSE for their entry in status[]), also
 *   decrementing the number of outstanding queries.
 */
void
process_responses(int adjust_rate) {
    double wait;
    struct timeval now, waituntil;
    double first_packet_wait = RESPONSE_BLOCKING_WAIT_TIME;
    unsigned int outstanding = queries_outstanding();

    if (adjust_rate == TRUE) {
        double u;

        u = time_of_first_query_sec +
            query_interval * num_queries_sent;
        waituntil.tv_sec = (long)floor(u);
        waituntil.tv_usec = (long)(1000000.0 * (u - waituntil.tv_sec));

        /*
         * Wait until a response arrives or the specified limit is
         * reached.
         */
        while (1) {
            set_timenow(&now);
            wait = difftv(waituntil, now);
            if (wait <= 0)
                wait = 0.0;
            if (data_available(wait) != TRUE)
                break;

            /*
             * We have reached the limit.  Read as many responses
             * as possible without waiting, and exit.
             */
            if (wait == 0) {
                while (data_available(0.0) == TRUE)
                    ;
                break;
            }
        }
    } else {
        /*
         * Don't block waiting for packets at all if we aren't
         * looking for any responses or if we are now able to send new
         * queries.
         */
        if ((outstanding == 0) ||
            (outstanding < max_queries_outstanding)) {
            first_packet_wait = 0.0;
        }

        if (data_available(first_packet_wait) == TRUE) {
            while (data_available(0.0) == TRUE)
                ;
        }
    }
}

/*
 * retire_old_queries:
 *   Go through the list of open queries (status[]) and remove any queries
 *   (i.e. set in_use = FALSE) which are older than the timeout, decrementing
 *   the number of queries outstanding for each one removed.
 */
void
retire_old_queries(int sending) {
    unsigned int count = 0;
    struct timeval curr_time;
    double timeout = query_timeout;
    int timeout_reduced = FALSE;

    /*
     * If we have target qps and would not be able to send any packets
     * due to buffer full, check whether we are behind the schedule.
     * If we are, purge some queries more aggressively.
     */
    if (target_qps > 0 && sending == TRUE && count == 0 &&
        queries_outstanding() == max_queries_outstanding) {
        struct timeval next, now;
        double n;

        n = time_of_first_query_sec +
            query_interval * num_queries_sent;
        next.tv_sec = (long)floor(n);
        next.tv_usec = (long)(1000000.0 * (n - next.tv_sec));

        set_timenow(&now);
        if (difftv(next, now) <= 0) {
            timeout_reduced = TRUE;
            timeout = 0.001; /* XXX: ad-hoc value */
        }
    }

    set_timenow(&curr_time);

    for (; count < query_status_allocated; count++) {
        if ((status[count].in_use == TRUE) &&
            (difftv(curr_time,
                status[count].sent_timestamp) >= (double)timeout))
        {
            status[count].in_use = FALSE;
            num_queries_outstanding--;

            if (timeout_queries != NULL) {
                struct query_mininfo *qi;

                qi = &timeout_queries[status[count].id];
                if (qi->qtype != -1) {
                    /* now really retire this query */
                    num_queries_timed_out++;
                    num_queries_timed_out_interval++;
                }
                qi->qtype = status[count].qtype;
                qi->sent_timestamp =
                    status[count].sent_timestamp;
                strcpy(qi->qname, status[count].qname);
            } else {
                num_queries_timed_out++;
                num_queries_timed_out_interval++;
            }

            if (timeout_reduced == FALSE) {
                if (status[count].desc) {
                    printf("> T %s\n", status[count].desc);
                    free(status[count].desc);
                } else {
                    printf("[Timeout] Query timed out: "
                           "msg id %u\n",
                           status[count].id);
                }
            }
        }
    }
}

/*
 * print_histogram
 *   Print RTT histogram to the specified file in the gnuplot format
 */
void
print_histogram(unsigned int total) {
    int i;
    double ratio;
    FILE *fp;

    if (rtt_histogram_file == NULL || rttarray == NULL)
        return;

    fp = fopen((const char *)rtt_histogram_file, "w+");
    if (fp == NULL) {
        fprintf(stderr, "Error opening RTT histogram file: %s\n",
            rtt_histogram_file);
        return;
    }

    for (i = 0; i < rttarray_size; i++) {
        ratio = ((double)rttarray[i] / (double)total) * 100;
        fprintf(fp, "%.6lf %.3lf\n",
            (double)(i * rttarray_unit) +
            (double)rttarray_unit / 2,
            ratio);
    }

    (void)fclose(fp);
}

/*
 * print_statistics:
 *   Print out statistics based on the results of the test
 */
void
print_statistics(int intermediate, unsigned int sent, unsigned int timed_out,
         unsigned int possibly_delayed,
         struct timeval *first_query,
         struct timeval *program_start,
         struct timeval *end_perf, struct timeval *end_query,
         unsigned int rcounted, double rmax, double rmin, double rtotal,
         unsigned int roverflows, unsigned int *rarray)
{
    unsigned int num_queries_completed;
    double per_lost, per_completed, per_lost2, per_completed2;
    double run_time, queries_per_sec, queries_per_sec2;
    double queries_per_sec_total;
    double rtt_average, rtt_stddev;
    struct timeval start_time;

    num_queries_completed = sent - timed_out;

    if (num_queries_completed == 0) {
        per_lost = 0.0;
        per_completed = 0.0;

        per_lost2 = 0.0;
        per_completed2 = 0.0;
    } else {
        per_lost = (100.0 * (double)timed_out) / (double)sent;
        per_completed = 100.0 - per_lost;

        per_lost2 = (100.0 * (double)(timed_out - possibly_delayed))
            / (double)sent;
        per_completed2 = 100 - per_lost2;
    }

    if (sent == 0) {
        start_time.tv_sec = program_start->tv_sec;
        start_time.tv_usec = program_start->tv_usec;
        run_time = 0.0;
        queries_per_sec = 0.0;
        queries_per_sec2 = 0.0;
        queries_per_sec_total = 0.0;
    } else {
        start_time.tv_sec = first_query->tv_sec;
        start_time.tv_usec = first_query->tv_usec;
        run_time = difftv(*end_perf, *first_query);
        queries_per_sec = (double)num_queries_completed / run_time;
        queries_per_sec2 = (double)(num_queries_completed +
                        possibly_delayed) / run_time;

        queries_per_sec_total = (double)sent /
            difftv(*end_query, *first_query);
    }

    if (rcounted > 0) {
        int i;
        double sum = 0;

        rtt_average = rtotal / (double)rcounted;
        for (i = 0; i < rttarray_size; i++) {
            if (rarray[i] != 0) {
                double mean, diff;

                mean = (double)(i * rttarray_unit) +
                (double)rttarray_unit / 2;
                diff = rtt_average - (mean / 1000000.0);
                sum += (diff * diff) * rarray[i];
            }
        }
        rtt_stddev = sqrt(sum / (double)rcounted);
    } else {
        rtt_average = 0.0;
        rtt_stddev = 0.0;
    }

    printf("\n");

    printf("%sStatistics:\n", intermediate ? "Intermediate " : "");

    printf("\n");

    if (!intermediate) {
        printf("  Parse input file:     %s\n",
               ((run_only_once == TRUE) ? "once" : "multiple times"));
        if (use_timelimit)
            printf("  Run time limit:       %u seconds\n",
                   run_timelimit);
        if (run_only_once == FALSE)
            printf("  Ran through file:     %u times\n",
                   runs_through_file);
        else
            printf("  Ended due to:         reaching %s\n",
                   ((runs_through_file == 0) ? "time limit"
                : "end of file"));

        printf("\n");
    }

    printf("  Queries sent:         %u queries\n", sent);
    printf("  Queries completed:    %u queries\n", num_queries_completed);
    printf("  Queries lost:         %u queries\n", timed_out);
    printf("  Queries delayed(?):   %u queries\n", possibly_delayed);

    printf("\n");

    printf("  RTT max:          %3.6lf sec\n", rmax);
    printf("  RTT min:              %3.6lf sec\n", rmin);
    printf("  RTT average:          %3.6lf sec\n", rtt_average);
    printf("  RTT std deviation:    %3.6lf sec\n", rtt_stddev);
    printf("  RTT out of range:     %u queries\n", roverflows);

    if (!intermediate)  /* XXX should we print this case also? */
        print_histogram(num_queries_completed);

    printf("\n");

    if (countrcodes) {
        unsigned int i;

        for (i = 0; i < 16; i++) {
            if (rcodecounts[i] == 0)
                continue;
            printf("  Returned %8s:    %u queries\n",
                   rcode_strings[i], rcodecounts[i]);
        }
        printf("\n");
    }

    printf("  Percentage completed: %6.2lf%%\n", per_completed);
    if (possibly_delayed > 0)
        printf("     (w/ delayed qrys): %6.2lf%%\n", per_completed2);
    printf("  Percentage lost:      %6.2lf%%\n", per_lost);
    if (possibly_delayed > 0)
        printf("    (w/o delayed qrys): %6.2lf%%\n", per_lost2);

    printf("\n");

    printf("  Started at:           %s",
           ctime((const time_t *)&start_time.tv_sec));
    printf("  Finished at:          %s",
           ctime((const time_t *)&end_perf->tv_sec));
    printf("  Ran for:              %.6lf seconds\n", run_time);

    printf("\n");

    printf("  Queries per second:   %.6lf qps\n", queries_per_sec);
    if (possibly_delayed > 0) {
        printf("   (w/ delayed qrys):   %.6lf qps\n",
               queries_per_sec2);
    }
    if (target_qps > 0) {
        printf("  Total QPS/target:     %.6lf/%d qps\n",
               queries_per_sec_total, target_qps);
    }

    printf("\n");
}

void
print_interval_statistics() {
    struct timeval time_now;

    if (use_timelimit == FALSE)
        return;

    if (setup_phase == TRUE)
        return;

    if (print_interval == 0)
        return;

    if (timelimit_reached() == TRUE)
        return;

    set_timenow(&time_now);
    if (difftv(time_now, time_of_first_query_interval)
        <= (double)print_interval)
        return;

    /* Don't count currently outstanding queries */
    num_queries_sent_interval -= queries_outstanding();
    print_statistics(TRUE, num_queries_sent_interval,
             num_queries_timed_out_interval,
             num_queries_possiblydelayed_interval,
             &time_of_first_query_interval,
             &time_of_first_query_interval, &time_now, &time_now,
             rtt_counted_interval, rtt_max_interval,
             rtt_min_interval, rtt_total_interval,
             rtt_overflows_interval, rttarray_interval);

    /* Reset intermediate counters */
    num_queries_sent_interval = 0;
    num_queries_timed_out_interval = 0;
    num_queries_possiblydelayed_interval = 0;
    rtt_max_interval = -1;
    rtt_min_interval = -1;
    rtt_total_interval = 0.0;
    rtt_counted_interval = 0.0;
    rtt_overflows_interval = 0;
    if (rttarray_interval != NULL) {
        memset(rttarray_interval, 0,
               sizeof(rttarray_interval[0]) * rttarray_size);
    }
}

/*
 * queryperf Program Mainline
 */
int
main(int argc, char **argv) {
    int adjust_rate;
    int sending = FALSE;
    int got_eof = FALSE;
    int input_length = MAX_INPUT_LEN;
    char input_line[MAX_INPUT_LEN + 1];

    set_timenow(&time_of_program_start);
    time_of_first_query.tv_sec = 0;
    time_of_first_query.tv_usec = 0;
    time_of_first_query_interval.tv_sec = 0;
    time_of_first_query_interval.tv_usec = 0;
    time_of_end_of_run.tv_sec = 0;
    time_of_end_of_run.tv_usec = 0;

    input_line[0] = '\0';

    show_startup_info();

    if (setup(argc, argv) == -1)
        return (-1);

    /* XXX: move this to setup: */
    timeout_queries = malloc(sizeof(struct query_mininfo) * 65536);
    if (timeout_queries == NULL) {
        fprintf(stderr,
            "failed to allocate memory for timeout queries\n");
        return (-1);
    } else {
        int i;
        for (i = 0; i < 65536; i++)
            timeout_queries[i].qtype = -1;
    }

    printf("[Status] Processing input data\n");

    while ((sending = keep_sending(&got_eof)) == TRUE ||
           queries_outstanding() > 0)
    {
        if (num_queries_sent_interval > 0){
            /*
             * After statistics are printed, send_query()
             * needs to be called at least once so that
             * time_of_first_query_interval is reset
             */
            print_interval_statistics();
        }
        adjust_rate = FALSE;

        while ((sending = keep_sending(&got_eof)) == TRUE &&
               queries_outstanding() < max_queries_outstanding)
        {
            int len = next_input_line(input_line, input_length);
            if (len == 0) {
                got_eof = TRUE;
            } else {
                /* Zap the trailing newline */
                if (input_line[len - 1] == '\n')
                    input_line[len - 1] = '\0';

                /*
                 * TODO: Should test if we got a whole line
                 * and flush to the next \n in input if not
                 * here... Add this later. Only do the next
                 * few lines if we got a whole line, else
                 * print a warning. Alternative: Make the
                 * max line size really big. BAD! :)
                 */

                if (input_line[0] == CONFIG_CHAR)
                    update_config(input_line);
                else {
                    send_query(input_line);
                    if (target_qps > 0 &&
                        (num_queries_sent %
                         max_queries_outstanding) == 0) {
                        adjust_rate = TRUE;
                    }
                }
            }
        }

        process_responses(adjust_rate);
        retire_old_queries(sending);
    }

    set_timenow(&time_of_end_of_run);

    printf("[Status] Testing complete\n");

    close_socket();
    close_datafile();

    print_statistics(FALSE, num_queries_sent, num_queries_timed_out,
             num_queries_possiblydelayed,
             &time_of_first_query, &time_of_program_start,
             &time_of_end_of_run, &time_of_stop_sending,
             rtt_counted, rtt_max, rtt_min, rtt_total,
             rtt_overflows, rttarray);

    return (0);
}