#include <unistd.h>
#include <netdb.h>
#include <errno.h>
#include <sys/select.h>
#include <sys/time.h>
#include <sys/types.h>
#include <fcntl.h>

/* handles select errors */
int my_select(int fd,fd_set *fdread, fd_set *fdwrite,fd_set *fdex,long sec, long usec)	{

	int ret_val;
	struct timeval stv;
	fd_set *fdr2,*fdw2,*fde2;
	
	stv.tv_sec=sec;
	stv.tv_usec=usec;
	fdr2=fdread;
	fdw2=fdwrite;
	fde2=fdex;
	
	ret_val=select(fd,fdr2,fdw2,fde2,&stv);
	   /* XXX select() sometimes return errno=EINTR (signal found) */
	while(ret_val==-1 && errno==EINTR)   {
		stv.tv_sec=sec;
		stv.tv_usec=usec;
		fdr2=fdread;
		fdw2=fdwrite;
		fde2=fdex;
		ret_val=select(fd,fdr2,fdw2,fde2,&stv);
	}
	return ret_val;
}



/*reads in a non-blocking way*/
ssize_t read_safe(int fd, void *buffer, size_t len) {

int r=0;
int total=0;
int toread=len;
fd_set  fr;
struct timeval tv;
int ret=0;
	
fcntl(fd,F_SETFL,O_NONBLOCK);
FD_ZERO(&fr);
FD_SET( fd, &fr);
tv.tv_sec=0;
tv.tv_usec=250000;

ret=select(fd+1,&fr,0,0,&tv);
/* XXX select() sometimes return errno=EINTR (signal found) */
while(ret==-1 && errno==EINTR) {
	ret=select(fd+1,&fr,0,0,&tv);
	tv.tv_sec=0;
	tv.tv_usec=250000;
}
   
if(ret<0) {
	perror("select");
        return -1;
}	


  if(ret>0)    {
	while((r=read(fd,buffer+total,toread))) {
		if(r==-1) {
	        	if(errno==EAGAIN) 
		     		break;
		         return -1;
	        }
	        total += r;
	        toread-=r;
	        if(total==len)
	        	return len;
		if(r==0)
			return 0;
       	}
  }
  return total;
}