#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <pthread.h>
#include <time.h>

#include "sim_pipe.h"
#include "rw_threads.h"

static int SendRemaining;
static int RecvRemaining;
static pthread_mutex_t Lock;
static pthread_cond_t Wait;
static int Go = 0;

double MyTime()
{
	struct timeval tv;
	gettimeofday(&tv,NULL);
	return((double)(tv.tv_sec)+((double)(tv.tv_usec)/1000000.0));
}


int
main(int argc, char *argv[])
{
	int nreaders;
	int nwriters;
	int buffsize;
	int totalsize;
	int quesize;
	int i;
	pthread_t *rthreads;
	pthread_t *wthreads;
	double start;
	double end;
	void *q;
	struct ThreadRec *t;
	int status;
	int id = 0;

	if(argc <= 5)
	{
		fprintf(stderr,
	"usage: testpipe nreaders nwriters buffsize quesize totalsize\n");
		fflush(stderr);
		exit(1);
	}

	nreaders = atoi(argv[1]);
	nwriters = atoi(argv[2]);
	buffsize = atoi(argv[3]);
	quesize = atoi(argv[4]);
	totalsize = atoi(argv[5]);

	pthread_mutex_init(&Lock,NULL);
	pthread_cond_init(&Wait,NULL);
	SendRemaining = totalsize;
	RecvRemaining = totalsize;

	/*
	 * make a que structure
	 */
	q = InitPipe(quesize);

	/*
	 * get space for reader and writer thread ids
	 */
	rthreads = (pthread_t *)malloc(nreaders*sizeof(pthread_t));
	if(rthreads == NULL)
	{
		exit(1);
	}
	wthreads = (pthread_t *)malloc(nwriters*sizeof(pthread_t));
	if(wthreads == NULL)
	{
		exit(1);
	}

	/*
	 * take the lock so none of the threads will run
	 * immediately
	 */
	pthread_mutex_lock(&Lock);

	/*
	 * spawn reader threads first
	 */
	id = 0;
	for(i=0; i < nreaders; i++)
	{
		t = (struct ThreadRec *)malloc(sizeof(struct ThreadRec));
		if(t == NULL)
		{
			exit(1);
		}
		t->q = q;
		t->buffsize = buffsize;
		t->Lock = &Lock;
		t->Wait = &Wait;
		t->SendRemaining = &SendRemaining;
		t->RecvRemaining = &RecvRemaining;
		t->Go = &Go;
		t->me = id;
		id++;
		status = pthread_create(&(rthreads[i]),
				        NULL,
					ReaderThread,
					(void *)t);
		if(status != 0)
		{
			exit(1);
		}
	}
	
	/*
	 * now the writers
	 */
	for(i=0; i < nwriters; i++)
	{
		t = (struct ThreadRec *)malloc(sizeof(struct ThreadRec));
		if(t == NULL)
		{
			exit(1);
		}
		t->q = q;
		t->buffsize = buffsize;
		t->Lock = &Lock;
		t->Wait = &Wait;
		t->SendRemaining = &SendRemaining;
		t->RecvRemaining = &RecvRemaining;
		t->Go = &Go;
		t->me = id;
		id++;
		status = pthread_create(&(wthreads[i]),
				        NULL,
					WriterThread,
					(void *)t);
		if(status != 0)
		{
			exit(1);
		}
	}

	/*
	 * start the timer
	 */
	start = MyTime();

	/*
	 * kick everybody off
	 */
	Go = 1;
	pthread_cond_broadcast(&Wait);
	pthread_mutex_unlock(&Lock);

	/*
	 * join with each reader and writer
	 */
	for(i=0; i < nreaders; i++)
	{
		status = pthread_join(rthreads[i],NULL);
		if(status != 0)
		{
			exit(1);
		}
	}
	for(i=0; i < nwriters; i++)
	{
		status = pthread_join(wthreads[i],NULL);
		if(status != 0)
		{
			exit(1);
		}
	}

	/*
	 * stop timer
	 */
	end = MyTime();
	FreePipe(q);

	printf("bw: %3.4f MB/s for %d readers, %d writers, %d buffsize, %d quesize %d total size\n",
		(double)(totalsize)/((end - start)*1000000.0),
		nreaders,
		nwriters,
		buffsize,
		quesize,
		totalsize);

	exit(0);
}