#import <CFNetwork/CFHost.h>
#import <netinet/in.h>
#import <netdb.h>
#import <SystemConfiguration/SystemConfiguration.h>
#pragma mark -
#pragma mark DNS解析和网络测试
-(NSString*) getAddressFromArray:(CFArrayRef) addresses
{
struct sockaddr *addr;
char ipAddress[INET6_ADDRSTRLEN];
CFIndex index, count;
int err;
assert(addresses != NULL);
count = CFArrayGetCount(addresses);
for (index = 0; index < count; index++) {
addr = (struct sockaddr *)CFDataGetBytePtr(CFArrayGetValueAtIndex(addresses, index));
assert(addr != NULL);
/* getnameinfo coverts an IPv4 or IPv6 address into a text string. */
err = getnameinfo(addr, addr->sa_len, ipAddress, INET6_ADDRSTRLEN, NULL, 0, NI_NUMERICHOST);
if (err == 0) {
NSLog(@"解析到ip地址：%s\n", ipAddress);
} else {
NSLog(@"地址格式转换错误：%d\n", err);
}
}
return [[[NSString alloc] initWithFormat:@"%s",ipAddress] autorelease];//这里只返回最后一个，一般认为只有一个地址
}
-(bool)getReachability:(CFDataRef) data withNameOrAddress:(CFStringRef) nameOrAddress
{
SCNetworkConnectionFlags *flags;
CFIndex length;
char *input;
Boolean success;
assert(data != NULL);
assert(nameOrAddress != NULL);
/* CFStringGetMaximumSizeForEncoding determines max bytes a string of specified length will take up if encoded. */
length = CFStringGetMaximumSizeForEncoding(CFStringGetLength(nameOrAddress), kCFStringEncodingASCII);
input = malloc(length + 1);
assert(input != NULL);
success = CFStringGetCString(nameOrAddress, input, length + 1, kCFStringEncodingASCII);
assert(success);
flags = (SCNetworkConnectionFlags *)CFDataGetBytePtr(data);
assert (flags != NULL);
/* If you only have a PPP interface enabled, the flags will be 0 because of a bug. <rdar://problem/3627771> */
if (*flags == 0) NSLog(@"%s -> Reachability Unknown\n", input);
if (*flags & kSCNetworkFlagsTransientConnection) NSLog(@"%s -> Transient Connection\n", input);
if (*flags & kSCNetworkFlagsReachable) {
NSLog(@"%s -> Reachable\n", input);
success = YES;
}else {
success = NO;
}
if (*flags & kSCNetworkFlagsConnectionRequired) NSLog(@"%s -> Connection Required\n", input);
if (*flags & kSCNetworkFlagsConnectionAutomatic) NSLog(@"%s -> Connection Automatic\n", input);
if (*flags & kSCNetworkFlagsInterventionRequired) NSLog(@"%s -> Intervention Required\n", input);
if (*flags & kSCNetworkFlagsIsLocalAddress) NSLog(@"%s -> Is Local Address\n", input);
if (*flags & kSCNetworkFlagsIsDirect) NSLog(@"%s -> Is Direct\n", input);
free(input);
return success;
}
-(void) serverResoluton{
CFStringRef hostName = (CFStringRef)self.serverInfo.serverAddress;
CFHostRef host;
CFStreamError error;
Boolean success;
CFArrayRef addressArray;
CFDataRef ReachableData;
assert(hostName != NULL);
/* Creates a new host object with the given name. */
host = CFHostCreateWithName(kCFAllocatorDefault, hostName);
assert(host != NULL);
success = CFHostStartInfoResolution(host, kCFHostAddresses, &error);
if (!success) {
NSLog(@"CFHostStartInfoResolution 返回错误 (%d, %ld)", error.domain, error.error);//如果解析地址失败，使用直接指定IP
NSLog(@"启用直接指定IP：%@",self.serverInfo.serverIPAddress);
[self.serverInfo.serverAddress release];
self.serverInfo.serverAddress = self.serverInfo.serverIPAddress;
}else {
addressArray = CFHostGetAddressing(host, nil);
[self.serverInfo.serverAddress release];
self.serverInfo.serverAddress = [[NSString alloc] initWithFormat:@"%@",[self getAddressFromArray:addressArray]];
NSLog(@"替换地址为：%@", self.serverInfo.serverAddress);
}
//使用新地址来确认可连接性
hostName = (CFStringRef)self.serverInfo.serverAddress;
host = CFHostCreateWithName(kCFAllocatorDefault, hostName);
success = CFHostStartInfoResolution(host, kCFHostReachability, &error);
if (!success) {
NSLog(@"CFHostStartInfoResolution 返回错误 (%d, %ld)", error.domain, error.error);
//暂不知到这里会在什么情况下发生
}else {
ReachableData = CFHostGetReachability(host, nil);
success = [self getReachability:ReachableData withNameOrAddress:(CFStringRef)hostName];
if (!success) {
[self.serverInfo.serverAddress release];
self.serverInfo.serverAddress = self.serverInfo.serverAddressBak;//在这里添加备用服务器
}
}
}