server.c

服务器端网络编程

		int sd;
		unsigned int sasize;
		int i;
		sasize=sizeof(*p_client_sa);
		if((sd=accept(s,(struct sockaddr *)p_client_sa,&sasize)),0)
		{
			perror("accept error");
			return(-1);
		}
		for(i=0;i<ClientNUM;i++)
		{
			if(p_client_sa->sin_addr.s_addr==ClientIP[i].s_addr)
			{
				printf("Authenticated User From %s Log In\n",inet_ntoa(p_client_sa->sin_addr));
				return sd;
			}
		}
		close(sd);
		printf("Not Authenticated User Log In\nRefuse to Offer Service\nConnection Closed\n");
		return(-1);
	}
	unsigned int gettimestamp()
	{
		char tmpbuf[12];
		unsigned int timestamp;
		struct tm *today;
		time_t ltime=time(NULL);
		today = localtime( &ltime );
		strftime( tmpbuf,12,"%y%m%d", today );
		//printf( tmpbuf );
		//timestamp = *((unsigned int*)tmpbuf);
		timestamp = atoi(tmpbuf);
		//printf("******%d******\n",timestamp);
		return timestamp;
	}
	unsigned int my_addr(int s)
	{
		struct sockaddr_in * psa;
		socklen_t len=sizeof(struct sockaddr_in);
		psa=(struct sockaddr_in *)malloc(sizeof(*psa));
		if(getsockname(s,(struct sockaddr *)psa,&len)==0)
		{
			return psa->sin_addr.s_addr;
		}
		return 0;
	}

	void head1_info_print(Message_Head1 * phead)
	{
		printf("\noper_type is %d\n",phead->oper_type);
		printf("packet_length is %d\n",phead->pack_length);
		printf("packet_date is %d\n",phead->pack_date);
		printf("head_length is %d\n",phead->head_length);
		printf("record_numb is %d\n",phead->record_numb);
	}
	void body1_info_print(Message_Body1 * pbody)
	{
		printf("\ntrader_serial is %d\n",pbody->trader_serial);
		printf("contract_id is %s\n",pbody->contract_id);
		printf("currency is %d\n",pbody->currency);
	}
	void body2_info_print(Message_Body2 * pbody)
	{
		printf("\ntrader_serial is %d\n",pbody->trader_serial);
		printf("contract_id is %s\n",pbody->contract_id);
		printf("account_balance is %d\n",pbody->account_balance);
	}
	void tail_info_print(Message_Tail * ptail)
	{
		struct in_addr temp;
		printf("\ntail_length is %d\n",ptail->tail_length);
		printf("tail_field_numb is %d\n",ptail->tail_field_numb);
		printf("tail_field_dat.traderid is %d\n",ptail->tail_field_data.trader_id);
		temp.s_addr=ptail->tail_field_data.trader_id;
		printf("traderid is %s\n",inet_ntoa(temp));
		printf("check code is %d\n",ptail->tail_field_data.check_code);

	}

	int checksum(Message_Head1 * phead,Message_Tail * ptail,struct sockaddr_in * p_client_sa)
	{
		unsigned int a,b;
		printf("the real IP is %d\n",p_client_sa->sin_addr.s_addr);
		printf("the real IP is %s\n",inet_ntoa(p_client_sa->sin_addr));
		a=(p_client_sa->sin_addr.s_addr+phead->pack_length)^phead->pack_date;
		b=ptail->tail_field_data.check_code;
		printf("caculated check_code is %d\n received check_code is %d\n",a,b);
		if(a!=b)    
		{
			printf("packet authentication error\n packet canceled\n");
			return -1;
		}
		return 0;
	}
	describe_body(short int oper_type,short int * precord_numb,DESCRIPT * pdescript)
	{
		switch(oper_type)
		{
			case 0x0001:
			case 0x0003:
				*precord_numb=3;
				pdescript[0].field_type='I';
				pdescript[0].field_length=4;
				pdescript[0].field_descript=1;
				pdescript[1].field_type='C';
				pdescript[1].field_length=20;
				pdescript[1].field_descript=2;
				pdescript[2].field_type='I';
				pdescript[2].field_length=4;
				pdescript[2].field_descript=3;
				break;
			case 0x0002:
			case 0x0004:
			case 0x0006:
				*precord_numb=4;
				pdescript[0].field_type='I';
				pdescript[0].field_length=4;
				pdescript[0].field_descript=1;
				pdescript[1].field_type='C';
				pdescript[1].field_length=20;
				pdescript[1].field_descript=2;
				pdescript[2].field_type='I';
				pdescript[2].field_length=4;
				pdescript[2].field_descript=4;
				pdescript[3].field_type='I';
				pdescript[3].field_length=1;
				pdescript[3].field_descript=5;
				break;
			case 0x0005:
				*precord_numb=3;
				pdescript[0].field_type='I';
				pdescript[0].field_length=4;
				pdescript[0].field_descript=1;
				pdescript[1].field_type='C';
				pdescript[1].field_length=20;
				pdescript[1].field_descript=2;
				pdescript[2].field_type='I';
				pdescript[2].field_length=4;
				pdescript[2].field_descript=4;
				break;
			default:
				printf("wrong oper_type");
		}

	}
	void describe_tail(DESCRIPT * pdescript)
	{
		pdescript[0].field_type='I';
		pdescript[0].field_length=4;
		pdescript[0].field_descript=7;
		pdescript[1].field_type='I';
		pdescript[1].field_length=4;
		pdescript[1].field_descript=8;
		pdescript[2].field_type='I';
		pdescript[2].field_length=4;
		pdescript[2].field_descript=9;
	}
	//Message_Head1 head_assemble1(short int oper_type)
	//{
	//  Message_Head1 head;
	//  head.oper_type=oper_type;
	//  head.pack_length=0;
	//  describe_body(oper_type,&(head.record_numb),head.descript);
	//  head.pack_date=gettimestamp();
	//  head.head_length=sizeof(head);
	//  return head;
	//}
	Message_Head2 head_assemble2(short int oper_type)
	{
		Message_Head2 head;
		head.oper_type=oper_type;
		head.pack_length=0;
		describe_body(oper_type,&(head.record_numb),head.descript);
		head.pack_date=gettimestamp();
		head.head_length=sizeof(head);
		return head;
	}

	Message_Tail tail_assemble(int sd,Message_Head2 * phead,Message_Body2 *pbody)
	{
		Message_Tail tail;
		tail.tail_length=sizeof(tail);
		tail.tail_field_numb=3;
		describe_tail(&tail.tail_field_descript);
		tail.tail_field_data.trader_id=my_addr(sd);
		tail.tail_field_data.check_code=(tail.tail_field_data.trader_id)^phead->pack_date;
		tail.tail_field_data.sum=pbody->account_balance;
		phead->pack_length=sizeof(*phead)+sizeof(*pbody)+sizeof(tail);
		return tail;
	}

	format2net(Message_Head2 * phead,Message_Body2 * pbody,Message_Tail * ptail)
	{
		int i;
		phead->oper_type=htons(phead->oper_type);
		phead->pack_length=htonl(phead->pack_length);
		phead->pack_date=htonl(phead->pack_date);
		phead->head_length=htons(phead->head_length);
		phead->record_numb=htons(phead->record_numb);
		for(i=0;i<4;i++)
		{
			phead->descript[i].field_descript=htons(phead->descript[i].field_descript);
		}
		pbody->trader_serial=htonl(pbody->trader_serial);
		pbody->account_balance=htonl(pbody->account_balance);
		ptail->tail_length=htons(ptail->tail_length);
		ptail->tail_field_numb=htons(ptail->tail_field_numb);
		for(i=0;i<1;i++)
		{
			ptail->tail_field_descript.field_descript=htons(ptail->tail_field_descript.field_descript);
		}
		ptail->tail_field_data.check_code=htonl(ptail->tail_field_data.check_code);
		ptail->tail_field_data.sum=htonl(ptail->tail_field_data.sum);
	}

	format2local(Message_Head1 * phead,Message_Body1 * pbody,Message_Tail * ptail)
	{
		int i;
		phead->oper_type=ntohs(phead->oper_type);
		phead->pack_length=ntohl(phead->pack_length);
		phead->pack_date=ntohl(phead->pack_date);
		phead->head_length=ntohs(phead->head_length);
		phead->record_numb=ntohs(phead->record_numb);
		for(i=0;i<3;i++)
		{
			phead->descript[i].field_descript=ntohs(phead->descript[i].field_descript);
		}

		pbody->trader_serial=ntohl(pbody->trader_serial);
		pbody->currency=ntohl(pbody->currency);

		ptail->tail_length=ntohs(ptail->tail_length);
		ptail->tail_field_numb=ntohs(ptail->tail_field_numb);
		for(i=0;i<1;i++)
		{
			ptail->tail_field_descript.field_descript=ntohs(ptail->tail_field_descript.field_descript);
		}
		ptail->tail_field_data.check_code=ntohl(ptail->tail_field_data.check_code);
		ptail->tail_field_data.sum=ntohl(ptail->tail_field_data.sum);
	}

int send_msg(short int oper_type,Message_Body2 body,int sd)
{
	unsigned char buff[256];
	Message_Head2 head;
	Message_Tail tail;
	memset(buff,0,sizeof(*buff));
	head=head_assemble2(oper_type);
	tail=tail_assemble(sd,&head,&body);
	format2net(&head,&body,&tail);
	//copy2buff(buff,&head,&body,&tail);
	memcpy(buff,&head,sizeof(head));
	memcpy(buff+sizeof(head),&body,sizeof(body));
	memcpy(buff+sizeof(head)+sizeof(body),&tail,sizeof(tail));
	if(send(sd,buff,sizeof(buff),0)<=0)
	{
		printf("ERROR in send message\n");
		return(-1);
	}
		printf("Success in send message\n");
	return(0);
}
int transaction(int sd,struct sockaddr_in * p_client_sa)
{
	unsigned char buff[256];
	int oper_type_back;
	Message_Head1 head;
	Message_Body1 body;
	Message_Tail tail;
	Message_Body2 body_back;
	memset(buff,0,sizeof(*buff));
	if(recv(sd,buff,sizeof(buff),0)<0)
	{
		printf("socket read failed\n");
		return(-1);
	}
	else
	{
		printf("Receive Request\n");
		//copy2buff(buff,&head,&body,&tail);
		memcpy(&head,buff,sizeof(head));
		memcpy(&body,(buff+sizeof(head)),sizeof(body));
		memcpy(&tail,(buff+sizeof(head)+sizeof(body)),sizeof(tail));
		if(checksum(&head,&tail,p_client_sa)<0)
			return(-1);
		format2local(&head,&body,&tail);
		head1_info_print(&head);
		body1_info_print(&body);
		tail_info_print(&tail);
		body_back.resp_type=accses(head.oper_type,body.trader_serial,body.contract_id,body.currency,&(body_back.account_balance));
		body_back.trader_serial=body.trader_serial;
		strcpy(body_back.contract_id,body.contract_id);
		//writelog(RecordFile,&head,&body,&tail);
		//close(sd);
		switch(head.oper_type)
		{
			case 0x0001:
				printf("deposit money to account\n");
				if(send_msg(0x0002,body_back,sd)<0)
				{
					if(affirm(1,body.trader_serial))
					{
						printf("roll back fail\n");
						writelog(RecordFile,&head,&body,&tail);
					}
					else
					{
						printf("roll back success\n");
					}
				}
				else
				{
					if(affirm(0,body.trader_serial)==26)
					writelog(RecordFile,&head,&body,&tail);
				}
				break;
				case 0x0003:
				printf("get money from account\n");
				if(send_msg(0x0004,body_back,sd)<0)
				{
					if(affirm(1,body.trader_serial))
					{
						printf("roll back fail\n");
						writelog(RecordFile,&head,&body,&tail);
					}
					else
					{
						printf("roll back success\n");
					}
				}
				else
				{
					affirm(0,body.trader_serial);
				}
				break;
				case 0x0005:
					printf("query account\n");
					send_msg(0x0006,body_back,sd);
					break;
				default:
					printf("wrong oper_type\n");
					return(-1);
			}
		}

		return(0);
	}
void clean(int sig)
{
	pid_t pid;
	int stat_val;
	//(void)signal(SIGCHLD,SIG_DFL);
	pid=waitpid(-1,&stat_val,WNOHANG);
	if(WIFEXITED(stat_val))
		printf("%d---Child exited with code %d\n",pid,WEXITSTATUS(stat_val));
	else
		printf("Child terminated abnormally\n");
}
int main(int argc,char *argv[])
{
	int s;
	int sd;
	struct sockaddr_in sa;
	struct sockaddr_in client_sa;
	//signal(SIGCHLD,clean);
	signal(SIGCHLD,SIG_IGN);
	readlog();
	sa=gethoststuff();
	s=opensocket();
	bindnlisten(s,sa);
	for(;;)
	{
		sd=acceptconn(s,&client_sa);
		if(sd!=-1)
		{
			if(fork()==0)
			{
				close(s);
				transaction(sd,&client_sa);
				printf("ended one trasaction\n");
				close(sd);
				exit(1);
			}
			else 
				close(sd);
		}

	}
	printf("press enter to quit\n");
	getchar();
	close(s);
}