#include "sched.h"
#include "pthread.h"
#include "stdio.h"
#include "stdlib.h"
#include "semaphore.h"
#include <cstring>
#include <unistd.h>

int producer(void *args);
int consumer(void *args);

pthread_mutex_t mutex;
sem_t product;
sem_t warehouse;
char buffer[8][4];
int bp = 0;

int main(int argc, char ** argv) {
    pthread_mutex_init(&mutex, NULL);
    sem_init(&product, 0, 0);
    sem_init(&warehouse, 0, 8);
    int clone_flag, arg, retval;
    char *stack;
    clone_flag = CLONE_VM | CLONE_SIGHAND | CLONE_FS | CLONE_FILES;
    int i;
    for (i = 0; i < 2; i++) {
        arg = i;
        stack = (char *)malloc(4096);
        retval = clone((int (*)(void*))producer, stack + 4095, clone_flag, (void *)&arg);
        free(stack);
        stack = (char *)malloc(4096);
        sleep(1);
        retval = clone((int (*)(void*))consumer, stack + 4095, clone_flag, (void *)&arg);
        free(stack);
    }
    sleep(30);
    exit(0);
}

int producer(void *args) {
    int id = *((int *)args);
    int i;
    for (i = 0; i < 10; i++) {
        sleep(i + 1);
        sem_wait(&warehouse);
        pthread_mutex_lock(&mutex);
        if (id == 0)
            strcpy(buffer[bp], "aaa\0");
        else
            strcpy(buffer[bp], "bbb\0");
        bp++;
        printf("producer%d produce %s in %d\n", id, buffer[bp - 1], bp - 1);
        pthread_mutex_unlock(&mutex);
        sem_post(&product);
    }
    printf("producer%d is over!\n", id);
    return 0;
}

int consumer(void *args) {
    int id = *((int *)args);
    int i;
    for (i = 0; i < 10; i++) {
        sleep(10 - i);
        sem_wait(&product);
        pthread_mutex_lock(&mutex);
        bp--;
        printf("consumer%d get %s in %d\n", id, buffer[bp], bp);
        strcpy(buffer[bp], "zzz\0");
        pthread_mutex_unlock(&mutex);
        sem_post(&warehouse);
    }
    printf("consumer%d is over!\n", id);
    return 0;
}