/*
 * main.c - integration-fixture entry point (plan todo 26).
 *
 * A REAL C23 program exercising both fixture features end to end:
 *   - pthread: pthread_create()/pthread_join() run a worker thread (guarded
 *     by the HAVE_PTHREAD define the generated config.h wrote), printing a
 *     grep-able marker the runner asserts on;
 *   - math: sin(0.5) from libm, printed with a fixed format the runner
 *     greps (the link would fail without -lm, so a successful run proves
 *     the LIBS accumulation reached the Makefile).
 *
 * _POSIX_C_SOURCE must be defined BEFORE the first include: under strict
 * -std=c23 glibc sets __STRICT_ANSI__ and hides pthread_create's
 * declaration, which C23 turns into an implicit-declaration ERROR
 * (the same trap recorded for src/ in the project learnings).
 */

#ifndef _POSIX_C_SOURCE
#define _POSIX_C_SOURCE 200809L
#endif

#include "config.h"
#include "demo.h"

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

#ifdef HAVE_PTHREAD
#include <pthread.h>

static void *
worker(void *arg)
{
    (void)arg;
    printf("worker thread ran\n");
    return NULL;
}
#endif

int
main(void)
{
    double s = sin(0.5);

    printf("hellothreads demo: sin(0.5) = %.4f\n", s);
    printf("demo_compute(2) = %d\n", demo_compute(2));
#ifdef HAVE_PTHREAD
    {
        pthread_t t;

        if (pthread_create(&t, NULL, worker, NULL) != 0) {
            fprintf(stderr, "pthread_create failed\n");
            return EXIT_FAILURE;
        }
        if (pthread_join(t, NULL) != 0) {
            fprintf(stderr, "pthread_join failed\n");
            return EXIT_FAILURE;
        }
    }
#endif
    return EXIT_SUCCESS;
}