Thread: Random IP Generation Program

Hello,I was Designing a Program that has two function the random_ip() and main()
the random_ip() returns an array of random generated ip address

Code:

#include<stdio.h>
#include<netinet/in.h>
#include<stdlib.h>
#include<string.h>
#include<sys/socket.h>
#include<arpa/inet.h>
#include<errno.h>

char* random_ip(char figure,int size,int check)//a thousand,mil,bil etc
{
	printf("Figure %c Size %d\n",figure,size);
	int i=65536;	
	int j=0;
	int  BUFSIZE;
	struct sockaddr_in temp;
	switch(figure)
	{
		case 't':
		BUFSIZE=(size*1024);
		break;

		case 'm':
		BUFSIZE=(size*1024*1024);
		break;
	
		case 'b':
		BUFSIZE=(size*1024*1024*1024);
		break;

		default:printf("Choose btn choices available!\n");
	}	
	printf("BUFSIZE %d\n",BUFSIZE);
	char *ip_buffer[BUFSIZE];
	srand(i);//seed the randomizer
	while(j<BUFSIZE)
	{
		ip_buffer[j]=(char*)malloc(16);
		temp.sin_addr.s_addr=(unsigned long)rand()%4294967295;

		ip_buffer[j]=(char*)malloc(16);

		strcpy(ip_buffer[j],inet_ntoa(temp.sin_addr));
		
		j++;
	
	}
	
	if(check){
	int a;
	int repeated=0;
	char*ip;
	for(j=0;j<BUFSIZE;j++)
	{
		ip=(char*)malloc(16);
		strcpy(ip,ip_buffer[j]);
		
		for(a=++j;a<BUFSIZE;a++)
		{	
			if((strcmp(ip,ip_buffer[a]))==0){//repeated ip	
				repeated++;	
				printf("\t\t\t\tFound %s repeated addresses.\n",ip);
			}	
		}	
		ip=NULL;
	}
	if(repeated>0)
	printf("Found %d repetead Addresses in %d Addresses.\n",repeated,BUFSIZE);
	}
	
return ip_buffer;
}
main(int argc,char**argv)
{

	int i=9;
	int j=0;
	int BUFSIZE;
	srand(i);//seed the randomizer
	switch((char)*argv[1])
	{
		case 't':
		BUFSIZE=(atoi(argv[2])*1024);
		break;

		case 'm':
		BUFSIZE=(atoi(argv[2])*1024*1024);
		break;
	
		case 'b':
		BUFSIZE=(atoi(argv[2])*1024*1024*1024);
		break;

		default:printf("Choose btn choices available!\n");
	}
	printf("BUFSIZE MAIN:%d\n",BUFSIZE);
	char *ip_buffer[BUFSIZE];
	memcpy(ip_buffer,random_ip((char)*argv[1],atoi(argv[2]),0),BUFSIZE);
	
	while(j<BUFSIZE)
	{
	printf("%s\t\t\t %d\n",ip_buffer[j],j);
	//printf("%s\n",inet_addr((char*)ip_buffer[j]));
	j++;
	
	}printf("%d Addresses\n",j);
	
}

it seems the code has a problem with the memcpy() function.Please Help figure this one out!
Thanks.

Care to share what the compiler error was exactly?

Why not save everyone a lot of time?

I have received compiler warnings that looks like

Code:

random_ip.c: In function ‘random_ip’:
random_ip.c:51: warning: this decimal constant is unsigned only in ISO C90
random_ip.c:83: warning: return from incompatible pointer type
random_ip.c:83: warning: function returns address of local variable

It has a 'Segmentation fault' Error At Runtime...

Thanks Tater!I tried once with 1024*1024 array size it work but too slow.


What size a program's stack is?It might be are reason why memcpy() fails

Thanks!I think I figure out some other solns for my "problem" :-)

Originally Posted by lvandaz

Thanks!I think I figure out some other solns for my "problem" :-)

Ummm.... what is a "soln" ?