iphone的IP地址源码

定义了几个方法，获取iphone的IP地址。

IPAdress.h

#define MAXADDRS    32
extern char *if_names[MAXADDRS];
extern char *ip_names[MAXADDRS];
extern char *hw_addrs[MAXADDRS];
extern unsigned long ip_addrs[MAXADDRS];
// Function prototypes
void InitAddresses();
void FreeAddresses();
void GetIPAddresses();
void GetHWAddresses();

 

IPAddress.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/sockio.h>
#include <net/if.h>
#include <errno.h>
#include <net/if_dl.h>
#include "GetAddresses.h"
#define min(a,b)    ((a) < (b) ? (a) : (b))
#define max(a,b)    ((a) > (b) ? (a) : (b))
#define BUFFERSIZE  4000
char *if_names[MAXADDRS];
char *ip_names[MAXADDRS];
char *hw_addrs[MAXADDRS];
unsigned long ip_addrs[MAXADDRS];
static int   nextAddr = 0;
void InitAddresses()
{
    int i;
    for (i=0; i<MAXADDRS; ++i)
    {
        if_names[i] = ip_names[i] = hw_addrs[i] = NULL;
        ip_addrs[i] = 0;
    }
}
void FreeAddresses()
{
    int i;
    for (i=0; i<MAXADDRS; ++i)
    {
        if (if_names[i] != 0) free(if_names[i]);
        if (ip_names[i] != 0) free(ip_names[i]);
        if (hw_addrs[i] != 0) free(hw_addrs[i]);
        ip_addrs[i] = 0;
    }
    InitAddresses();
}
void GetIPAddresses()
{
    int                 i, len, flags;
    char                buffer[BUFFERSIZE], *ptr, lastname[IFNAMSIZ], *cptr;
    struct ifconf       ifc;
    struct ifreq        *ifr, ifrcopy;
    struct sockaddr_in  *sin;
    char temp[80];
    int sockfd;
    for (i=0; i<MAXADDRS; ++i)
    {
        if_names[i] = ip_names[i] = NULL;
        ip_addrs[i] = 0;
    }
    sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0)
    {
        perror("socket failed");
        return;
    }

    ifc.ifc_len = BUFFERSIZE;
    ifc.ifc_buf = buffer;

    if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0)
    {
        perror("ioctl error");
        return;
    }

    lastname[0] = 0;

    for (ptr = buffer; ptr < buffer + ifc.ifc_len; )
    {
        ifr = (struct ifreq *)ptr;
        len = max(sizeof(struct sockaddr), ifr->ifr_addr.sa_len);
        ptr += sizeof(ifr->ifr_name) + len;  // for next one in buffer

        if (ifr->ifr_addr.sa_family != AF_INET)
        {
            continue;   // ignore if not desired address family
        }

        if ((cptr = (char *)strchr(ifr->ifr_name, ':')) != NULL)
        {
            *cptr = 0;      // replace colon will null
        }

        if (strncmp(lastname, ifr->ifr_name, IFNAMSIZ) == 0)
        {
            continue;   /* already processed this interface */
        }

        memcpy(lastname, ifr->ifr_name, IFNAMSIZ);

        ifrcopy = *ifr;
        ioctl(sockfd, SIOCGIFFLAGS, &ifrcopy);
        flags = ifrcopy.ifr_flags;
        if ((flags & IFF_UP) == 0)
        {
            continue;   // ignore if interface not up
        }

        if_names[nextAddr] = (char *)malloc(strlen(ifr->ifr_name)+1);
        if (if_names[nextAddr] == NULL)
        {
            return;
        }
        strcpy(if_names[nextAddr], ifr->ifr_name);

        sin = (struct sockaddr_in *)&ifr->ifr_addr;
        strcpy(temp, inet_ntoa(sin->sin_addr));

        ip_names[nextAddr] = (char *)malloc(strlen(temp)+1);
        if (ip_names[nextAddr] == NULL)
        {
            return;
        }
        strcpy(ip_names[nextAddr], temp);
        ip_addrs[nextAddr] = sin->sin_addr.s_addr;
        ++nextAddr;
    }

    close(sockfd);
}
void GetHWAddresses()
{
   struct ifconf ifc;
   struct ifreq *ifr;
   int i, sockfd;
   char buffer[BUFFERSIZE], *cp, *cplim;
   char temp[80];
   for (i=0; i<MAXADDRS; ++i)
   {
      hw_addrs[i] = NULL;
   }
   sockfd = socket(AF_INET, SOCK_DGRAM, 0);
   if (sockfd < 0)
   {
      perror("socket failed");
      return;
   }
   ifc.ifc_len = BUFFERSIZE;
   ifc.ifc_buf = buffer;
   if (ioctl(sockfd, SIOCGIFCONF, (char *)&ifc) < 0)
   {
      perror("ioctl error");
      close(sockfd);
      return;
   }
   ifr = ifc.ifc_req;
   cplim = buffer + ifc.ifc_len;
   for (cp=buffer; cp < cplim; )
   {
      ifr = (struct ifreq *)cp;
      if (ifr->ifr_addr.sa_family == AF_LINK)
      {
         struct sockaddr_dl *sdl = (struct sockaddr_dl *)&ifr->ifr_addr;
         int a,b,c,d,e,f;
         int i;
         strcpy(temp, (char *)ether_ntoa(LLADDR(sdl)));
         sscanf(temp, "%x:%x:%x:%x:%x:%x", &a, &b, &c, &d, &e, &f);
         sprintf(temp, "%02X:%02X:%02X:%02X:%02X:%02X",a,b,c,d,e,f);
         for (i=0; i<MAXADDRS; ++i)
         {
            if ((if_names[i] != NULL) && (strcmp(ifr->ifr_name, if_names[i]) == 0))
            {
               if (hw_addrs[i] == NULL)
               {
                  hw_addrs[i] = (char *)malloc(strlen(temp)+1);
                  strcpy(hw_addrs[i], temp);
                  break;
               }
            }
        }
      }
      cp += sizeof(ifr->ifr_name) + max(sizeof(ifr->ifr_addr), ifr->ifr_addr.sa_len);
   }
   close(sockfd);
}

 

如何用呢， 我们在MyAppAppDelegate.h中如下

#import <UIKit/UIKit.h>
@interface MyAppAppDelegate : NSObject <UIApplicationDelegate> {
    NSString *localIP;
}
@property (nonatomic, retain) NSString *localIP;
- (NSString *)deviceIPAdress;
@end

 

MyAppDelegate.m

- (void)applicationDidFinishLaunching:(UIApplication *)application {
    self.localIP = [self deviceIPAdress];
        ...
}
- (NSString *)deviceIPAdress {
    InitAddresses();
    GetIPAddresses();
    GetHWAddresses();

        /*
    int i;
    NSString *deviceIP;
    for (i=0; i<MAXADDRS; ++i)
    {
        static unsigned long localHost = 0x7F000001;        // 127.0.0.1
        unsigned long theAddr;

        theAddr = ip_addrs[i];

        if (theAddr == 0) break;
        if (theAddr == localHost) continue;

        NSLog(@"%s %s %s/n", if_names[i], hw_addrs[i], ip_names[i]);
    }
    deviceIP = [NSString stringWithFormat:@"%s", ip_names[i]];
    */

        //this will get you the right IP from your device in format like 198.111.222.444. If you use the for loop above you will se that ip_names array will also contain localhost IP 127.0.0.1 that's why I don't use it. Eventualy this was code from mac that's why it uses arrays for ip_names as macs can have multiple IPs
    return [NSString stringWithFormat:@"%s", ip_names[1]];
}