Condition.c

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/*
 * Objectively: Ultra-lightweight object oriented framework for GNU C.
 * Copyright (C) 2014 Jay Dolan <jay@jaydolan.com>
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
#include <assert.h>
 
#include <errno.h>
#include <stdlib.h>
#include <string.h>
 
#include <pthread.h>
 
#include "Condition.h"
 
#define _Class _Condition
 
#pragma mark - Object
 
static void dealloc(Object *self) {
 
    Condition *this = (Condition *) self;
 
    pthread_cond_destroy(this->condition);
    free(this->condition);
 
    super(Object, self, dealloc);
}
 
#pragma mark - Condition
 
static void broadcast(Condition *self) {
 
    int err = pthread_cond_broadcast(self->condition);
    assert(err == 0);
}
 
static Condition *init(Condition *self) {
 
    self = (Condition *) super(Lock, self, init);
    if (self) {
 
        self->condition = calloc(1, sizeof(pthread_cond_t));
        assert(self->condition);
 
        const int err = pthread_cond_init(self->condition, NULL);
        assert(err == 0);
    }
 
    return self;
}
 
static void _signal(Condition *self) {
 
    int err = pthread_cond_signal(self->condition);
    assert(err == 0);
}
 
static void _wait(Condition *self) {
 
    int err = pthread_cond_wait(self->condition, self->lock.lock);
    assert(err == 0);
}
 
static _Bool waitUntilDate(Condition *self, const Date *date) {
 
    Lock *lock = (Lock *) self;
 
    const struct timespec time = {
        .tv_sec = date->time.tv_sec,
        .tv_nsec = date->time.tv_usec * 1000
    };
 
    int err = pthread_cond_timedwait(self->condition, lock->lock, &time);
    assert(err == 0 || err == ETIMEDOUT);
 
    return err == 0;
}
 
#pragma mark - Class lifecycle
 
static void initialize(Class *clazz) {
 
    ((ObjectInterface *) clazz->interface)->dealloc = dealloc;
 
    ((ConditionInterface *) clazz->interface)->broadcast = broadcast;
    ((ConditionInterface *) clazz->interface)->init = init;
    ((ConditionInterface *) clazz->interface)->signal = _signal;
    ((ConditionInterface *) clazz->interface)->wait = _wait;
    ((ConditionInterface *) clazz->interface)->waitUntilDate = waitUntilDate;
}
 
Class *_Condition(void) {
    static Class *clazz;
    static Once once;
 
    do_once(&once, {
        clazz = _initialize(&(const ClassDef) {
            .name = "Condition",
            .superclass = _Lock(),
            .instanceSize = sizeof(Condition),
            .interfaceOffset = offsetof(Condition, interface),
            .interfaceSize = sizeof(ConditionInterface),
            .initialize = initialize,
        });
    });
 
    return clazz;
}
 
#undef _Class