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193 | /*
* Copyright 2021 Jeisson Hidalgo-Cespedes - Universidad de Costa Rica
*/
#include <assert.h>
#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include "simulation.h"
int simulate_producer_consumer(shared_thread_data_t* shared_data) {
assert(shared_data);
int error = 0;
if (shared_data) {
error += queue_init(&shared_data->queue);
error += sem_init(&shared_data->can_consume, /*pshared*/0, 0);
error += pthread_mutex_init(&shared_data->stdout_mutex, /*attr*/NULL);
error += pthread_mutex_init(&shared_data->next_product_mutex
, /*attr*/NULL);
if (error == 0) {
struct timespec start_time, finish_time;
clock_gettime(/*clk_id*/CLOCK_MONOTONIC, &start_time);
error = create_threads(shared_data);
clock_gettime(/*clk_id*/CLOCK_MONOTONIC, &finish_time);
double elapsed_time = finish_time.tv_sec - start_time.tv_sec +
(finish_time.tv_nsec - start_time.tv_nsec) * 1e-9;
printf("execution time: %.9lfs\n", elapsed_time);
pthread_mutex_destroy(&shared_data->next_product_mutex);
pthread_mutex_destroy(&shared_data->stdout_mutex);
} else {
fprintf(stderr, "error: could not init mutex\n");
error = 11;
}
queue_free(&shared_data->queue);
queue_destroy(&shared_data->queue);
free(shared_data);
} else {
fprintf(stderr, "error: could not allocated shared memory\n");
error = 12;
}
return error;
}
int create_threads(shared_thread_data_t* shared_data) {
assert(shared_data);
int error = 0;
const size_t thread_count = shared_data->producer_count
+ shared_data->consumer_count;
pthread_t* threads = (pthread_t*) malloc(thread_count * sizeof(pthread_t));
private_thread_data_t* private_data = (private_thread_data_t*)
calloc(thread_count, sizeof(private_thread_data_t));
if (threads && private_data) {
for (size_t index = 0; index < shared_data->producer_count; ++index) {
private_data[index].thread_number = index;
private_data[index].shared_data = shared_data;
error = pthread_create(&threads[index], NULL, produce
, &private_data[index]);
if (error) {
fprintf(stderr, "error: could not create thread %zu\n", index);
error = 21;
break;
}
}
for (size_t index = 0; index < shared_data->consumer_count; ++index) {
const size_t array_index = shared_data->producer_count + index;
private_data[array_index].thread_number = index;
private_data[array_index].shared_data = shared_data;
error = pthread_create(&threads[array_index], NULL, consume
, &private_data[array_index]);
if (error) {
fprintf(stderr, "error: could not create thread %zu\n", array_index);
error = 21;
break;
}
}
for (size_t index = 0; index < thread_count; ++index) {
pthread_join(threads[index], NULL);
}
free(private_data);
free(threads);
} else {
fprintf(stderr, "error: could not allocate memory for %zu threads\n"
, thread_count);
error = 22;
}
return error;
}
void* produce(void* data) {
assert(data);
private_thread_data_t* private_data = (private_thread_data_t*)data;
shared_thread_data_t *shared_data = private_data->shared_data;
struct timespec time;
clock_gettime(/*clk_id*/CLOCK_MONOTONIC, &time);
unsigned int seed = time.tv_nsec;
while (true) {
pthread_mutex_lock(&shared_data->next_product_mutex);
const size_t product_index = shared_data->next_product_index++;
pthread_mutex_unlock(&shared_data->next_product_mutex);
if (product_index >= shared_data->product_count) {
// Give all consumers an opportunity to leave the semaphor
if (product_index >= shared_data->product_count
+ shared_data->producer_count - 1) {
printf("All producers finished\n");
for (size_t index = 0; index < shared_data->consumer_count; ++index) {
sem_post(&shared_data->can_consume);
}
}
break;
}
random_delay(shared_data->min_producer_delay
, shared_data->max_producer_delay, &seed);
pthread_mutex_lock(&shared_data->stdout_mutex);
printf("%zu produced %zu\n", private_data->thread_number
, product_index + 1);
pthread_mutex_unlock(&shared_data->stdout_mutex);
queue_append(&shared_data->queue, product_index);
sem_post(&shared_data->can_consume);
}
return NULL;
}
void* consume(void* data) {
assert(data);
private_thread_data_t* private_data = (private_thread_data_t*)data;
shared_thread_data_t *shared_data = private_data->shared_data;
struct timespec time;
clock_gettime(/*clk_id*/CLOCK_MONOTONIC, &time);
unsigned int seed = time.tv_nsec;
while (true) {
sem_wait(&shared_data->can_consume);
if (queue_is_empty(&shared_data->queue)) {
break;
}
size_t product_index = queue_dequeue(&shared_data->queue);
pthread_mutex_lock(&shared_data->stdout_mutex);
printf("\t\t%zu consuming %zu\n", private_data->thread_number
, product_index + 1);
pthread_mutex_unlock(&shared_data->stdout_mutex);
random_delay(shared_data->min_consumer_delay
, shared_data->max_consumer_delay, &seed);
// pthread_mutex_lock(&shared_data->stdout_mutex);
// printf("\t\t%zu consumed %zu\n", private_data->thread_number
// , product_index + 1);
// pthread_mutex_unlock(&shared_data->stdout_mutex);
}
return NULL;
}
void random_delay(useconds_t min, useconds_t max, unsigned* seedp) {
assert(min <= max);
useconds_t milliseconds = min;
if (max > min) {
milliseconds += rand_r(seedp) % (max - min);
}
usleep(milliseconds * 1000);
}
|