qemu/qemu-sockets.c
Amos Kong 4d5b97da35 cleanup useless return sentence
This patch cleans up return sentences in the end of void functions.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
2012-10-05 15:10:21 +02:00

830 lines
23 KiB
C

/*
* inet and unix socket functions for qemu
*
* (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; under version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <unistd.h>
#include "qemu_socket.h"
#include "qemu-common.h" /* for qemu_isdigit */
#include "main-loop.h"
#ifndef AI_ADDRCONFIG
# define AI_ADDRCONFIG 0
#endif
static const int on=1, off=0;
/* used temporarely until all users are converted to QemuOpts */
static QemuOptsList dummy_opts = {
.name = "dummy",
.head = QTAILQ_HEAD_INITIALIZER(dummy_opts.head),
.desc = {
{
.name = "path",
.type = QEMU_OPT_STRING,
},{
.name = "host",
.type = QEMU_OPT_STRING,
},{
.name = "port",
.type = QEMU_OPT_STRING,
},{
.name = "to",
.type = QEMU_OPT_NUMBER,
},{
.name = "ipv4",
.type = QEMU_OPT_BOOL,
},{
.name = "ipv6",
.type = QEMU_OPT_BOOL,
},
{ /* end if list */ }
},
};
static int inet_getport(struct addrinfo *e)
{
struct sockaddr_in *i4;
struct sockaddr_in6 *i6;
switch (e->ai_family) {
case PF_INET6:
i6 = (void*)e->ai_addr;
return ntohs(i6->sin6_port);
case PF_INET:
i4 = (void*)e->ai_addr;
return ntohs(i4->sin_port);
default:
return 0;
}
}
static void inet_setport(struct addrinfo *e, int port)
{
struct sockaddr_in *i4;
struct sockaddr_in6 *i6;
switch (e->ai_family) {
case PF_INET6:
i6 = (void*)e->ai_addr;
i6->sin6_port = htons(port);
break;
case PF_INET:
i4 = (void*)e->ai_addr;
i4->sin_port = htons(port);
break;
}
}
const char *inet_strfamily(int family)
{
switch (family) {
case PF_INET6: return "ipv6";
case PF_INET: return "ipv4";
case PF_UNIX: return "unix";
}
return "unknown";
}
int inet_listen_opts(QemuOpts *opts, int port_offset, Error **errp)
{
struct addrinfo ai,*res,*e;
const char *addr;
char port[33];
char uaddr[INET6_ADDRSTRLEN+1];
char uport[33];
int slisten, rc, to, port_min, port_max, p;
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
ai.ai_family = PF_UNSPEC;
ai.ai_socktype = SOCK_STREAM;
if ((qemu_opt_get(opts, "host") == NULL) ||
(qemu_opt_get(opts, "port") == NULL)) {
fprintf(stderr, "%s: host and/or port not specified\n", __FUNCTION__);
error_set(errp, QERR_SOCKET_CREATE_FAILED);
return -1;
}
pstrcpy(port, sizeof(port), qemu_opt_get(opts, "port"));
addr = qemu_opt_get(opts, "host");
to = qemu_opt_get_number(opts, "to", 0);
if (qemu_opt_get_bool(opts, "ipv4", 0))
ai.ai_family = PF_INET;
if (qemu_opt_get_bool(opts, "ipv6", 0))
ai.ai_family = PF_INET6;
/* lookup */
if (port_offset)
snprintf(port, sizeof(port), "%d", atoi(port) + port_offset);
rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);
if (rc != 0) {
fprintf(stderr,"getaddrinfo(%s,%s): %s\n", addr, port,
gai_strerror(rc));
error_set(errp, QERR_SOCKET_CREATE_FAILED);
return -1;
}
/* create socket + bind */
for (e = res; e != NULL; e = e->ai_next) {
getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
uaddr,INET6_ADDRSTRLEN,uport,32,
NI_NUMERICHOST | NI_NUMERICSERV);
slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
if (slisten < 0) {
fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
inet_strfamily(e->ai_family), strerror(errno));
if (!e->ai_next) {
error_set(errp, QERR_SOCKET_CREATE_FAILED);
}
continue;
}
setsockopt(slisten,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
#ifdef IPV6_V6ONLY
if (e->ai_family == PF_INET6) {
/* listen on both ipv4 and ipv6 */
setsockopt(slisten,IPPROTO_IPV6,IPV6_V6ONLY,(void*)&off,
sizeof(off));
}
#endif
port_min = inet_getport(e);
port_max = to ? to + port_offset : port_min;
for (p = port_min; p <= port_max; p++) {
inet_setport(e, p);
if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {
goto listen;
}
if (p == port_max) {
fprintf(stderr,"%s: bind(%s,%s,%d): %s\n", __FUNCTION__,
inet_strfamily(e->ai_family), uaddr, inet_getport(e),
strerror(errno));
if (!e->ai_next) {
error_set(errp, QERR_SOCKET_BIND_FAILED);
}
}
}
closesocket(slisten);
}
fprintf(stderr, "%s: FAILED\n", __FUNCTION__);
freeaddrinfo(res);
return -1;
listen:
if (listen(slisten,1) != 0) {
error_set(errp, QERR_SOCKET_LISTEN_FAILED);
perror("listen");
closesocket(slisten);
freeaddrinfo(res);
return -1;
}
snprintf(uport, sizeof(uport), "%d", inet_getport(e) - port_offset);
qemu_opt_set(opts, "host", uaddr);
qemu_opt_set(opts, "port", uport);
qemu_opt_set(opts, "ipv6", (e->ai_family == PF_INET6) ? "on" : "off");
qemu_opt_set(opts, "ipv4", (e->ai_family != PF_INET6) ? "on" : "off");
freeaddrinfo(res);
return slisten;
}
#ifdef _WIN32
#define QEMU_SOCKET_RC_INPROGRESS(rc) \
((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
#else
#define QEMU_SOCKET_RC_INPROGRESS(rc) \
((rc) == -EINPROGRESS)
#endif
/* Struct to store connect state for non blocking connect */
typedef struct ConnectState {
int fd;
struct addrinfo *addr_list;
struct addrinfo *current_addr;
NonBlockingConnectHandler *callback;
void *opaque;
} ConnectState;
static int inet_connect_addr(struct addrinfo *addr, bool *in_progress,
ConnectState *connect_state);
static void wait_for_connect(void *opaque)
{
ConnectState *s = opaque;
int val = 0, rc = 0;
socklen_t valsize = sizeof(val);
bool in_progress;
qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
do {
rc = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, (void *) &val, &valsize);
} while (rc == -1 && socket_error() == EINTR);
/* update rc to contain error */
if (!rc && val) {
rc = -1;
}
/* connect error */
if (rc < 0) {
closesocket(s->fd);
s->fd = rc;
}
/* try to connect to the next address on the list */
while (s->current_addr->ai_next != NULL && s->fd < 0) {
s->current_addr = s->current_addr->ai_next;
s->fd = inet_connect_addr(s->current_addr, &in_progress, s);
/* connect in progress */
if (in_progress) {
return;
}
}
freeaddrinfo(s->addr_list);
if (s->callback) {
s->callback(s->fd, s->opaque);
}
g_free(s);
}
static int inet_connect_addr(struct addrinfo *addr, bool *in_progress,
ConnectState *connect_state)
{
int sock, rc;
*in_progress = false;
sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
if (sock < 0) {
fprintf(stderr, "%s: socket(%s): %s\n", __func__,
inet_strfamily(addr->ai_family), strerror(errno));
return -1;
}
qemu_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
if (connect_state != NULL) {
socket_set_nonblock(sock);
}
/* connect to peer */
do {
rc = 0;
if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
rc = -socket_error();
}
} while (rc == -EINTR);
if (connect_state != NULL && QEMU_SOCKET_RC_INPROGRESS(rc)) {
connect_state->fd = sock;
qemu_set_fd_handler2(sock, NULL, NULL, wait_for_connect,
connect_state);
*in_progress = true;
} else if (rc < 0) {
closesocket(sock);
return -1;
}
return sock;
}
static struct addrinfo *inet_parse_connect_opts(QemuOpts *opts, Error **errp)
{
struct addrinfo ai, *res;
int rc;
const char *addr;
const char *port;
memset(&ai, 0, sizeof(ai));
ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
ai.ai_family = PF_UNSPEC;
ai.ai_socktype = SOCK_STREAM;
addr = qemu_opt_get(opts, "host");
port = qemu_opt_get(opts, "port");
if (addr == NULL || port == NULL) {
fprintf(stderr,
"inet_parse_connect_opts: host and/or port not specified\n");
error_set(errp, QERR_SOCKET_CREATE_FAILED);
return NULL;
}
if (qemu_opt_get_bool(opts, "ipv4", 0)) {
ai.ai_family = PF_INET;
}
if (qemu_opt_get_bool(opts, "ipv6", 0)) {
ai.ai_family = PF_INET6;
}
/* lookup */
rc = getaddrinfo(addr, port, &ai, &res);
if (rc != 0) {
fprintf(stderr, "getaddrinfo(%s,%s): %s\n", addr, port,
gai_strerror(rc));
error_set(errp, QERR_SOCKET_CREATE_FAILED);
return NULL;
}
return res;
}
/**
* Create a socket and connect it to an address.
*
* @opts: QEMU options, recognized parameters strings "host" and "port",
* bools "ipv4" and "ipv6".
* @errp: set on error
* @callback: callback function for non-blocking connect
* @opaque: opaque for callback function
*
* Returns: -1 on error, file descriptor on success.
*
* If @callback is non-null, the connect is non-blocking. If this
* function succeeds, callback will be called when the connection
* completes, with the file descriptor on success, or -1 on error.
*/
int inet_connect_opts(QemuOpts *opts, Error **errp,
NonBlockingConnectHandler *callback, void *opaque)
{
struct addrinfo *res, *e;
int sock = -1;
bool in_progress;
ConnectState *connect_state = NULL;
res = inet_parse_connect_opts(opts, errp);
if (!res) {
return -1;
}
if (callback != NULL) {
connect_state = g_malloc0(sizeof(*connect_state));
connect_state->addr_list = res;
connect_state->callback = callback;
connect_state->opaque = opaque;
}
for (e = res; e != NULL; e = e->ai_next) {
if (connect_state != NULL) {
connect_state->current_addr = e;
}
sock = inet_connect_addr(e, &in_progress, connect_state);
if (in_progress) {
return sock;
} else if (sock >= 0) {
/* non blocking socket immediate success, call callback */
if (callback != NULL) {
callback(sock, opaque);
}
break;
}
}
if (sock < 0) {
error_set(errp, QERR_SOCKET_CONNECT_FAILED);
}
g_free(connect_state);
freeaddrinfo(res);
return sock;
}
int inet_dgram_opts(QemuOpts *opts)
{
struct addrinfo ai, *peer = NULL, *local = NULL;
const char *addr;
const char *port;
char uaddr[INET6_ADDRSTRLEN+1];
char uport[33];
int sock = -1, rc;
/* lookup peer addr */
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
ai.ai_family = PF_UNSPEC;
ai.ai_socktype = SOCK_DGRAM;
addr = qemu_opt_get(opts, "host");
port = qemu_opt_get(opts, "port");
if (addr == NULL || strlen(addr) == 0) {
addr = "localhost";
}
if (port == NULL || strlen(port) == 0) {
fprintf(stderr, "inet_dgram: port not specified\n");
return -1;
}
if (qemu_opt_get_bool(opts, "ipv4", 0))
ai.ai_family = PF_INET;
if (qemu_opt_get_bool(opts, "ipv6", 0))
ai.ai_family = PF_INET6;
if (0 != (rc = getaddrinfo(addr, port, &ai, &peer))) {
fprintf(stderr,"getaddrinfo(%s,%s): %s\n", addr, port,
gai_strerror(rc));
return -1;
}
/* lookup local addr */
memset(&ai,0, sizeof(ai));
ai.ai_flags = AI_PASSIVE;
ai.ai_family = peer->ai_family;
ai.ai_socktype = SOCK_DGRAM;
addr = qemu_opt_get(opts, "localaddr");
port = qemu_opt_get(opts, "localport");
if (addr == NULL || strlen(addr) == 0) {
addr = NULL;
}
if (!port || strlen(port) == 0)
port = "0";
if (0 != (rc = getaddrinfo(addr, port, &ai, &local))) {
fprintf(stderr,"getaddrinfo(%s,%s): %s\n", addr, port,
gai_strerror(rc));
goto err;
}
/* create socket */
sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
if (sock < 0) {
fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
inet_strfamily(peer->ai_family), strerror(errno));
goto err;
}
setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
/* bind socket */
if (getnameinfo((struct sockaddr*)local->ai_addr,local->ai_addrlen,
uaddr,INET6_ADDRSTRLEN,uport,32,
NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
fprintf(stderr, "%s: getnameinfo: oops\n", __FUNCTION__);
goto err;
}
if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
fprintf(stderr,"%s: bind(%s,%s,%d): OK\n", __FUNCTION__,
inet_strfamily(local->ai_family), uaddr, inet_getport(local));
goto err;
}
/* connect to peer */
if (getnameinfo((struct sockaddr*)peer->ai_addr, peer->ai_addrlen,
uaddr, INET6_ADDRSTRLEN, uport, 32,
NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
fprintf(stderr, "%s: getnameinfo: oops\n", __FUNCTION__);
goto err;
}
if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
fprintf(stderr, "%s: connect(%s,%s,%s,%s): %s\n", __FUNCTION__,
inet_strfamily(peer->ai_family),
peer->ai_canonname, uaddr, uport, strerror(errno));
goto err;
}
freeaddrinfo(local);
freeaddrinfo(peer);
return sock;
err:
if (-1 != sock)
closesocket(sock);
if (local)
freeaddrinfo(local);
if (peer)
freeaddrinfo(peer);
return -1;
}
/* compatibility wrapper */
static int inet_parse(QemuOpts *opts, const char *str)
{
const char *optstr, *h;
char addr[64];
char port[33];
int pos;
/* parse address */
if (str[0] == ':') {
/* no host given */
addr[0] = '\0';
if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {
fprintf(stderr, "%s: portonly parse error (%s)\n",
__FUNCTION__, str);
return -1;
}
} else if (str[0] == '[') {
/* IPv6 addr */
if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {
fprintf(stderr, "%s: ipv6 parse error (%s)\n",
__FUNCTION__, str);
return -1;
}
qemu_opt_set(opts, "ipv6", "on");
} else if (qemu_isdigit(str[0])) {
/* IPv4 addr */
if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {
fprintf(stderr, "%s: ipv4 parse error (%s)\n",
__FUNCTION__, str);
return -1;
}
qemu_opt_set(opts, "ipv4", "on");
} else {
/* hostname */
if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {
fprintf(stderr, "%s: hostname parse error (%s)\n",
__FUNCTION__, str);
return -1;
}
}
qemu_opt_set(opts, "host", addr);
qemu_opt_set(opts, "port", port);
/* parse options */
optstr = str + pos;
h = strstr(optstr, ",to=");
if (h)
qemu_opt_set(opts, "to", h+4);
if (strstr(optstr, ",ipv4"))
qemu_opt_set(opts, "ipv4", "on");
if (strstr(optstr, ",ipv6"))
qemu_opt_set(opts, "ipv6", "on");
return 0;
}
int inet_listen(const char *str, char *ostr, int olen,
int socktype, int port_offset, Error **errp)
{
QemuOpts *opts;
char *optstr;
int sock = -1;
opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL);
if (inet_parse(opts, str) == 0) {
sock = inet_listen_opts(opts, port_offset, errp);
if (sock != -1 && ostr) {
optstr = strchr(str, ',');
if (qemu_opt_get_bool(opts, "ipv6", 0)) {
snprintf(ostr, olen, "[%s]:%s%s",
qemu_opt_get(opts, "host"),
qemu_opt_get(opts, "port"),
optstr ? optstr : "");
} else {
snprintf(ostr, olen, "%s:%s%s",
qemu_opt_get(opts, "host"),
qemu_opt_get(opts, "port"),
optstr ? optstr : "");
}
}
} else {
error_set(errp, QERR_SOCKET_CREATE_FAILED);
}
qemu_opts_del(opts);
return sock;
}
/**
* Create a blocking socket and connect it to an address.
*
* @str: address string
* @errp: set in case of an error
*
* Returns -1 in case of error, file descriptor on success
**/
int inet_connect(const char *str, Error **errp)
{
QemuOpts *opts;
int sock = -1;
opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL);
if (inet_parse(opts, str) == 0) {
sock = inet_connect_opts(opts, errp, NULL, NULL);
} else {
error_set(errp, QERR_SOCKET_CREATE_FAILED);
}
qemu_opts_del(opts);
return sock;
}
/**
* Create a non-blocking socket and connect it to an address.
* Calls the callback function with fd in case of success or -1 in case of
* error.
*
* @str: address string
* @callback: callback function that is called when connect completes,
* cannot be NULL.
* @opaque: opaque for callback function
* @errp: set in case of an error
*
* Returns: -1 on immediate error, file descriptor on success.
**/
int inet_nonblocking_connect(const char *str,
NonBlockingConnectHandler *callback,
void *opaque, Error **errp)
{
QemuOpts *opts;
int sock = -1;
g_assert(callback != NULL);
opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL);
if (inet_parse(opts, str) == 0) {
sock = inet_connect_opts(opts, errp, callback, opaque);
} else {
error_set(errp, QERR_SOCKET_CREATE_FAILED);
}
qemu_opts_del(opts);
return sock;
}
#ifndef _WIN32
int unix_listen_opts(QemuOpts *opts)
{
struct sockaddr_un un;
const char *path = qemu_opt_get(opts, "path");
int sock, fd;
sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket(unix)");
return -1;
}
memset(&un, 0, sizeof(un));
un.sun_family = AF_UNIX;
if (path && strlen(path)) {
snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
} else {
char *tmpdir = getenv("TMPDIR");
snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX",
tmpdir ? tmpdir : "/tmp");
/*
* This dummy fd usage silences the mktemp() unsecure warning.
* Using mkstemp() doesn't make things more secure here
* though. bind() complains about existing files, so we have
* to unlink first and thus re-open the race window. The
* worst case possible is bind() failing, i.e. a DoS attack.
*/
fd = mkstemp(un.sun_path); close(fd);
qemu_opt_set(opts, "path", un.sun_path);
}
unlink(un.sun_path);
if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno));
goto err;
}
if (listen(sock, 1) < 0) {
fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno));
goto err;
}
return sock;
err:
closesocket(sock);
return -1;
}
int unix_connect_opts(QemuOpts *opts)
{
struct sockaddr_un un;
const char *path = qemu_opt_get(opts, "path");
int sock;
if (NULL == path) {
fprintf(stderr, "unix connect: no path specified\n");
return -1;
}
sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket(unix)");
return -1;
}
memset(&un, 0, sizeof(un));
un.sun_family = AF_UNIX;
snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno));
close(sock);
return -1;
}
return sock;
}
/* compatibility wrapper */
int unix_listen(const char *str, char *ostr, int olen)
{
QemuOpts *opts;
char *path, *optstr;
int sock, len;
opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL);
optstr = strchr(str, ',');
if (optstr) {
len = optstr - str;
if (len) {
path = g_malloc(len+1);
snprintf(path, len+1, "%.*s", len, str);
qemu_opt_set(opts, "path", path);
g_free(path);
}
} else {
qemu_opt_set(opts, "path", str);
}
sock = unix_listen_opts(opts);
if (sock != -1 && ostr)
snprintf(ostr, olen, "%s%s", qemu_opt_get(opts, "path"), optstr ? optstr : "");
qemu_opts_del(opts);
return sock;
}
int unix_connect(const char *path)
{
QemuOpts *opts;
int sock;
opts = qemu_opts_create(&dummy_opts, NULL, 0, NULL);
qemu_opt_set(opts, "path", path);
sock = unix_connect_opts(opts);
qemu_opts_del(opts);
return sock;
}
#else
int unix_listen_opts(QemuOpts *opts)
{
fprintf(stderr, "unix sockets are not available on windows\n");
errno = ENOTSUP;
return -1;
}
int unix_connect_opts(QemuOpts *opts)
{
fprintf(stderr, "unix sockets are not available on windows\n");
errno = ENOTSUP;
return -1;
}
int unix_listen(const char *path, char *ostr, int olen)
{
fprintf(stderr, "unix sockets are not available on windows\n");
errno = ENOTSUP;
return -1;
}
int unix_connect(const char *path)
{
fprintf(stderr, "unix sockets are not available on windows\n");
errno = ENOTSUP;
return -1;
}
#endif
#ifdef _WIN32
static void socket_cleanup(void)
{
WSACleanup();
}
#endif
int socket_init(void)
{
#ifdef _WIN32
WSADATA Data;
int ret, err;
ret = WSAStartup(MAKEWORD(2,2), &Data);
if (ret != 0) {
err = WSAGetLastError();
fprintf(stderr, "WSAStartup: %d\n", err);
return -1;
}
atexit(socket_cleanup);
#endif
return 0;
}