Pa_setup_server_PL5

/**
* @file server.c
* @brief Description
* @date 2017-10-29
* @author name of author
*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <assert.h>
#include <time.h>
#include <arpa/inet.h>
#include <sys/socket.h>

#include "debug.h"
#include "memory.h"
#include "common.h"
#include "server_args.h"

#define MAX_PORT    (1 << 16)

int setup_server(int port, int type, int backlog);
int validate_port_number(int port);

int main(int argc, char *argv[])
{
    struct gengetopt_args_info args;

    // gengetopt parser: deve ser a primeira linha de código no main
    if( cmdline_parser(argc, argv, &args) ){
        ERROR(1, "Erro: execução de cmdline_parser\n");
    }

    int port = validate_port_number(args.port_arg);

    int backlog = 0;
    int sock = setup_server(port, SOCK_DGRAM, backlog);

    close(sock);

    // gengetopt: libertar recurso
    cmdline_parser_free(&args);

    return 0;
}


int validate_port_number(int port){
    if( port < 0 || port >= MAX_PORT ){ // antes estava >
        fprintf(stderr,"invalid port number (%d)\n", port);
        exit(5);
    }
    return port;
}

/* @return socket already binded locally */
int setup_server(int port, int type, int backlog){
    assert( port > 0 || port < MAX_PORT );
    assert(type==SOCK_DGRAM || type==SOCK_STREAM);
    assert( (type==SOCK_STREAM && backlog > 0) || (type==SOCK_DGRAM));

    int sock = socket(AF_INET, type, 0);
    if( sock == -1 ){
        ERROR(1,"Cannot create socket");
    }


    struct sockaddr_in  my_addr;
    memset(&my_addr,0,sizeof(my_addr));
    my_addr.sin_family = AF_INET;
    my_addr.sin_port = htons(port);
    my_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    int ret_bind=bind(sock,(struct sockaddr*)&my_addr,sizeof(my_addr));
    if( ret_bind == -1 ){
        ERROR(2,"Cannot bind socket (port=%d)\n", port);
    }

    if( type == SOCK_STREAM ){
        int ret_listen = listen(sock, backlog);
        if( ret_listen == -1 ){
            ERROR(3,"Cannot listen");
        }
    }

    printf("[SERVER] bind port %d\n", port);
    return sock;
}