duration.c

/*
 * Copyright (c) 2009 NLNet Labs. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <ctype.h>
#include <ldns/ldns.h>
#include "utilities.h"
#include "proto.h"
#include "duration.h"
#include "logging.h"

static const char* duration_str = "duration";


/**
 * Create a new 'instant' duration.
 *
 */
duration_type*
duration_create(void)
{
    duration_type* duration;

    CHECKALLOC(duration = (duration_type*) malloc(sizeof(duration_type)));
    duration->years = 0;
    duration->months = 0;
    duration->weeks = 0;
    duration->days = 0;
    duration->hours = 0;
    duration->minutes = 0;
    duration->seconds = 0;
    return duration;
}


/**
 * Compare durations.
 *
 */
int
duration_compare(duration_type* d1, duration_type* d2)
{
    if (!d1 && !d2) {
        return 0;
    }
    if (!d1 || !d2) {
        return d1?-1:1;
    }

    if (d1->years != d2->years) {
        return d1->years - d2->years;
    }
    if (d1->months != d2->months) {
        return d1->months - d2->months;
    }
    if (d1->weeks != d2->weeks) {
        return d1->weeks - d2->weeks;
    }
    if (d1->days != d2->days) {
        return d1->days - d2->days;
    }
    if (d1->hours != d2->hours) {
        return d1->hours - d2->hours;
    }
    if (d1->minutes != d2->minutes) {
        return d1->minutes - d2->minutes;
    }
    if (d1->seconds != d2->seconds) {
        return d1->seconds - d2->seconds;
    }

    return 0;
}


/**
 * Create a duration from string.
 *
 */
duration_type*
duration_create_from_string(const char* str)
{
    duration_type* duration = duration_create();
    char* P, *X, *T, *W;
    int not_weeks = 0;

    if (!duration) {
        ods_log_error("[%s] cannot create from string %s: create failed",
            duration_str, str);
        return NULL;
    }
    if (!str) {
        return duration;
    }

    P = strchr(str, 'P');
    if (!P) {
        ods_log_error("[%s] cannot create from string %s: P not found",
            duration_str, str);
        duration_cleanup(duration);
        return NULL;
    }

    T = strchr(str, 'T');
    X = strchr(str, 'Y');
    if (X) {
        duration->years = atoi(str+1);
        str = X;
        not_weeks = 1;
    }
    X = strchr(str, 'M');
    if (X && (!T || (size_t) (X-P) < (size_t) (T-P))) {
        duration->months = atoi(str+1);
        str = X;
        not_weeks = 1;
    }
    X = strchr(str, 'D');
    if (X) {
        duration->days = atoi(str+1);
        str = X;
        not_weeks = 1;
    }
    if (T) {
        str = T;
        not_weeks = 1;
    }
    X = strchr(str, 'H');
    if (X && T) {
        duration->hours = atoi(str+1);
        str = X;
        not_weeks = 1;
    }
    X = strrchr(str, 'M');
    if (X && T && (size_t) (X-P) > (size_t) (T-P)) {
        duration->minutes = atoi(str+1);
        str = X;
        not_weeks = 1;
    }
    X = strchr(str, 'S');
    if (X && T) {
        duration->seconds = atoi(str+1);
        str = X;
        not_weeks = 1;
    }

    W = strchr(str, 'W');
    if (W) {
        if (not_weeks) {
            ods_log_error("[%s] cannot create from string: parse error",
                duration_str);
            duration_cleanup(duration);
            return NULL;
        } else {
            duration->weeks = atoi(str+1);
            str = W;
        }
    }
    return duration;
}


/**
 * Get the number of digits in a number.
 *
 */
static size_t
digits_in_number(time_t duration)
{
    uint32_t period = (uint32_t) duration;
    size_t count = 0;
    if (!period) {
        return 1;
    }
    while (period > 0) {
        count++;
        period /= 10;
    }
    return count;
}


/**
 * Convert a duration to a string.
 *
 */
char*
duration2string(duration_type* duration)
{
    char* str = NULL, *num = NULL;
    size_t count = 2;
    int T = 0, D = 0;

    if (!duration) {
        return NULL;
    }

    if (duration->years > 0) {
        count = count + 1 + digits_in_number(duration->years);
        D = 1;
    }
    if (duration->months > 0) {
        count = count + 1 + digits_in_number(duration->months);
        D = 1;
    }
    if (duration->weeks > 0) {
        count = count + 1 + digits_in_number(duration->weeks);
        D = 1;
    }
    if (duration->days > 0) {
        count = count + 1 + digits_in_number(duration->days);
        D = 1;
    }
    if (duration->hours > 0) {
        count = count + 1 + digits_in_number(duration->hours);
        T = 1;
    }
    if (duration->minutes > 0) {
        count = count + 1 + digits_in_number(duration->minutes);
        T = 1;
    }
    if (duration->seconds > 0 ||
        (!D && !duration->hours && !duration->minutes)) {
        count = count + 1 + digits_in_number(duration->seconds);
        T = 1;
    }
    if (T) {
        count++;
    }

    str = (char*) calloc(count, sizeof(char));
    str[0] = 'P';
    str[1] = '\0';

    if (duration->years > 0) {
        count = digits_in_number(duration->years);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uY", (uint32_t) duration->years);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    if (duration->months > 0) {
        count = digits_in_number(duration->months);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uM", (uint32_t) duration->months);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    if (duration->weeks > 0) {
        count = digits_in_number(duration->weeks);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
            snprintf(num, count+2, "%uW", (uint32_t) duration->weeks);
            str = strncat(str, num, count+2);
            free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    if (duration->days > 0) {
        count = digits_in_number(duration->days);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uD", (uint32_t) duration->days);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    if (T) {
        str = strncat(str, "T", 1);
    }
    if (duration->hours > 0) {
        count = digits_in_number(duration->hours);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uH", (uint32_t) duration->hours);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    if (duration->minutes > 0) {
        count = digits_in_number(duration->minutes);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uM", (uint32_t) duration->minutes);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
    }
    }
    if (duration->seconds > 0 ||
        (!D && !duration->hours && !duration->minutes)) {
        count = digits_in_number(duration->seconds);
        num = (char*) calloc(count+2, sizeof(char));
        if (num) {
        snprintf(num, count+2, "%uS", (uint32_t) duration->seconds);
        str = strncat(str, num, count+2);
        free((void*) num);
        } else {
            goto duration2string_num_calloc_failed;
        }
    }
    return str;

duration2string_num_calloc_failed:
    ods_log_error("[%s] cannot create string: malloc error", duration_str);
    free((void*) str);
    return NULL;
}


/**
 * Convert a duration to a time.
 *
 */
time_t
duration2time(duration_type* duration)
{
    time_t period = 0;
    char* dstr = NULL;

    if (duration) {
        period += (duration->seconds);
        period += (duration->minutes)*60;
        period += (duration->hours)*3600;
        period += (duration->days)*86400;
        period += (duration->weeks)*86400*7;
        period += (duration->months)*86400*31;
        period += (duration->years)*86400*365;

        if (duration->months || duration->years) {
            /* [TODO] calculate correct number of days in this month/year */
            dstr = duration2string(duration);
            free((void*) dstr);
        }
    }
    return period;
}

/**
 * Set the duration based on a time_t.
 */
int duration_set_time(duration_type* duration, time_t time) {
    if (!duration) {
        return 1;
    }

    duration->years = time / (86400*365);
    time -= duration->years * 86400*365;
    duration->months = time / (86400*31);
    time -= duration->months * 86400*31;
    duration->days = time / 86400;
    time -= duration->days * 86400;
    duration->hours = time / 3600;
    time -= duration->hours * 3600;
    duration->minutes = time / 60;
    time -= duration->minutes * 60;
    duration->seconds = time;
    
    duration->weeks = 0;

    return 0;
}

/**
 * Return a random time.
 *
 */
time_t
ods_rand(time_t mod)
{
#ifdef HAVE_ARC4RANDOM_UNIFORM
    return (time_t) (arc4random_uniform((uint32_t) mod+1));
#elif HAVE_ARC4RANDOM
    return (time_t) (arc4random() % (unsigned) mod+1);
#else
    return (time_t) (random() % (unsigned) mod+1);
#endif
}

static time_t time_now_set = 0;

/**
 * Set the time_now to a new value.
 * As long as this value is later than the real time now 
 * the overriden value is returned.
 *
 */
void
set_time_now(time_t now)
{
    time_now_set = now;
}

int
set_time_now_str(char* time_arg)
{
    char* endptr;
    time_t epoch;
    struct tm tm;
    if (time_arg == NULL) {
        epoch = 0;
    } else if (strptime(time_arg, "%Y-%m-%d-%H:%M:%S", &tm)) {
        tm.tm_isdst = -1; /* OS handles daylight savings */
        epoch = mktime(&tm);
    } else {
        while (isspace(*time_arg))
            ++time_arg;
        epoch = strtol(time_arg, &endptr, 0);
        if (endptr != time_arg) {
            while (isspace(*endptr))
                ++endptr;
            if (*endptr != '\0')
                return -1;
        } else
            return -2;
    }
    set_time_now(epoch);
    return 0;
}

/**
 * Return the time since Epoch, measured in seconds.
 *
 */
time_t
time_now(void)
{
    return time_now_set ? time_now_set: time(NULL);
}

/**
 * copycode: This code is based on the EXAMPLE in the strftime manual.
 *
 */
uint32_t
time_datestamp(time_t tt, const char* format, char** str)
{
    time_t t;
    struct tm datetime;
    struct tm *tmp;
    uint32_t ut = 0;
    char outstr[32];

    if (tt) {
        t = tt;
    } else {
        t = time_now();
    }

    tmp = localtime_r(&t,&datetime);
    if (tmp == NULL) {
        ods_log_error("[%s] time_datestamp: localtime_r() failed", duration_str);
        return 0;
    }

    if (strftime(outstr, sizeof(outstr), format, tmp) == 0) {
        ods_log_error("[%s] time_datestamp: strftime() failed", duration_str);
        return 0;
    }

    ut = (uint32_t) strtoul(outstr, NULL, 10);
    if (str) {
        *str = strdup(outstr);
    }
    return ut;
}

/**
 * Clean up duration.
 *
 */
void
duration_cleanup(duration_type* duration)
{
    if (!duration) {
        return;
    }
    free(duration);
}