/* myloggerd.c
 * Source file for thread-lab
 * Creates a server to log messages sent from various connections
 * in real time.
 *
 * Student:
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <stdlib.h>
#include <pthread.h>
#include "message-lib.h"
#define BUFSIZE 512

// forward declarations
int usage( char name[] );
// a function to be executed by each thread
void * recv_log_msgs( void * arg );

// globals
int log_fd; // opened by main() but accessible by each thread

void * recv_log_msgs( void * arg ){

	// loops to receive messages from a connection;
	// when read_msg returns zero, terminate the loop
	// and close the connection
	printf("Thread launched");
	int c;
	char buf[BUFSIZE];
	int connection = *((int *) arg);
	while((c = read_msg(connection, buf, BUFSIZE)) > 0){
		write(log_fd, buf, c);
	}
	close_connection((long) arg);
	return NULL;
}

int usage( char name[] ){
	printf( "Usage:\n" );
	printf( "\t%s <log-file-name> <UDS path>\n", name );
	return 1;
}

int main( int argc, char * argv[] )
{
	if ( argc != 3 )
		return usage( argv[0] );
	// open the log file for appending
	log_fd = open(argv[1], O_RDWR | O_APPEND| O_CREAT, 0666);
	//Having a pre-existing udslogger file sometimes makes the program not work properly
	unlink(argv[2]);
	// permit message connections
	int listener = permit_connections( argv[2] );
	pthread_t tid;
	// loop to accept message connections;
	// as each connection is accepted,
	// launch a new thread that calls
	// recv_log_msgs(), which receives
	// messages and writes them to the log file
	// when accept_next_connection returns -1, terminate the loop
	int connection;
	while((connection = accept_next_connection(listener)) != -1){
		pthread_create(&tid, NULL, recv_log_msgs, &connection);
	}
	// close the listener
	close(listener);
	// close the log file
	close(log_fd);
	return 0;
}