要在Android NDK中使用libresolv进行DNS解析,可以按照以下步骤进行:
在你的Android项目中创建一个C/C++文件,例如dns_resolver.c。
在dns_resolver.c文件中添加以下代码:
#include
#include
const char* resolve_dns(const char* hostname) {
struct addrinfo hints, *res;
int status;
char ipstr[INET6_ADDRSTRLEN];
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC; // AF_INET or AF_INET6 to force version
hints.ai_socktype = SOCK_STREAM;
if ((status = getaddrinfo(hostname, NULL, &hints, &res)) != 0) {
return NULL;
}
void* addr;
if (res->ai_family == AF_INET) {
struct sockaddr_in* ipv4 = (struct sockaddr_in*)res->ai_addr;
addr = &(ipv4->sin_addr);
} else {
struct sockaddr_in6* ipv6 = (struct sockaddr_in6*)res->ai_addr;
addr = &(ipv6->sin6_addr);
}
inet_ntop(res->ai_family, addr, ipstr, sizeof ipstr);
freeaddrinfo(res);
return ipstr;
}
add_library(dns_resolver SHARED dns_resolver.c)
public class MainActivity extends AppCompatActivity {
static {
System.loadLibrary("dns_resolver");
}
private native String resolveDNS(String hostname);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String hostname = "example.com";
String ip = resolveDNS(hostname);
Log.d("DNS", "Resolved IP for " + hostname + ": " + ip);
}
}
请注意,libresolv在Android NDK中可用,但在将来的Android版本中可能会有所改变。因此,这种方法可能会在未来的Android版本中不再适用。