source: MondoRescue/branches/stable/mindi-busybox/libbb/xconnect.c@ 821

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Connect to host at port using address resolution from getaddrinfo
 *
 */

#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <errno.h>
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "libbb.h"

/* Return network byte ordered port number for a service.
 * If "port" is a number use it as the port.
 * If "port" is a name it is looked up in /etc/services, if it isnt found return
 * default_port
 */
unsigned short bb_lookup_port(const char *port, const char *protocol, unsigned short default_port)
{
    unsigned short port_nr = htons(default_port);
    if (port) {
        char *endptr;
        int old_errno;
        long port_long;

        /* Since this is a lib function, we're not allowed to reset errno to 0.
         * Doing so could break an app that is deferring checking of errno. */
        old_errno = errno;
        errno = 0;
        port_long = strtol(port, &endptr, 10);
        if (errno != 0 || *endptr!='\0' || endptr==port || port_long < 0 || port_long > 65535) {
            struct servent *tserv = getservbyname(port, protocol);
            if (tserv) {
                port_nr = tserv->s_port;
            }
        } else {
            port_nr = htons(port_long);
        }
        errno = old_errno;
    }
    return port_nr;
}

void bb_lookup_host(struct sockaddr_in *s_in, const char *host)
{
    struct hostent *he;

    memset(s_in, 0, sizeof(struct sockaddr_in));
    s_in->sin_family = AF_INET;
    he = xgethostbyname(host);
    memcpy(&(s_in->sin_addr), he->h_addr_list[0], he->h_length);
}

int xconnect(struct sockaddr_in *s_addr)
{
    int s = bb_xsocket(AF_INET, SOCK_STREAM, 0);
    if (connect(s, (struct sockaddr *)s_addr, sizeof(struct sockaddr_in)) < 0)
    {
        if (ENABLE_FEATURE_CLEAN_UP) close(s);
        bb_perror_msg_and_die("Unable to connect to remote host (%s)",
                inet_ntoa(s_addr->sin_addr));
    }
    return s;
}