int start_udp_recv(int fd, struct sockaddr_in *addr ,int *id)
{
_Argument argv;
bzero(&argv, sizeof(_Argument));
int writfd;
pid_t pid;
key_t key;
int qmsg_id;
ssize_t n;
int try_cnt = 2;
*id = -1;
pid = getpid();
argv.pid = pid;
argv.addr = *addr;
argv.sockfd = fd;
if ( (writfd = open(SERV_FIFO, O_WRONLY, 0)) < 0)
return NG;
if ( (n = write(writfd, &argv, sizeof(_Argument)) < 0)) //提交接收请求
return NG;
if ( (key = get_ipc_key(pid)) == NG)
return NG;
printf("ipc_key create is %d\n", key);
sleep(1);
try_again:
qmsg_id = msgget(key, IPC_EXCL);
if ( qmsg_id < 0) {
if (EEXIST == errno) {
printf("This key is exist.\n");
qmsg_id = msgget(key, 0); //连接消息队列
printf("消息队列： ipc_id = %d\n", qmsg_id);
if (qmsg_id < 0)
return NG;
}
else {
if (--try_cnt) {
sleep(1); //等待udp服务端启动线程
goto try_again;
} else {
return NG;
}
}
}
*id = qmsg_id;
return OK;
}
int main(int argc, char **argv)
{
FILE *stdlog = stderr;
char action;
int i;
long *vertices;
long vertices_quantity;
order_msgbuf message;
respond_msgbuf result;
int msgid;
if(argc < 2)
fatal("ERROR: Too few arguments.");
action = argv[1][0]; /* First char of second arg. */
switch(action) {
case '+':
if(argc != 5)
fatal("Wrong number of arguments. `+` requires 3 additional "
"args: `from` vertex, `to` vertex and edge weight.");
message.order = order_add_edge(atoi(argv[2]), atoi(argv[3]),
atoi(argv[4]));
break;
case '-':
if(argc != 4)
fatal("Wrong number of arguments. `-` requires 2 additional "
"args: `from` vertex and `to` vertex.");
message.order = order_remove_edge(atoi(argv[2]), atoi(argv[3]));
break;
case 'H':
if(argc < 3)
fatal("Wrong number of arguments. `H` requires at least "
"1 vertex.");
if(argc > 52)
fatal("Wrong number of arguments. `H` works with max of 50 "
"vertices (but beware that H has cost higher than"
"exponential).");
vertices_quantity = argc - 2;
if((vertices = calloc((size_t) (vertices_quantity), sizeof(long)))
== NULL)
syserr("calloc: When allocating space for vertices.");
for(i = 0; i < vertices_quantity; i ++)
vertices[i] = (long) atoi(argv[i + 2]);
message.order = order_hamiltonian_cycle(vertices_quantity,
vertices);
break;
default:
fatal("Invalid command. You ought to use `+`, `-` or `H` "
"as your first argument.");
}
message.msg_type = IPC_ORDERS_RESERVED;
message.order.client_pid = (long) getpid();
if((msgid = msgget(get_ipc_key(), 0666)) == -1)
syserr("msgget: While receiving IPC id.");
if(msgsnd(msgid, &message, sizeof(order_t), 0) != 0)
syserr("msgsnd: While sending order.");
if(msgrcv(msgid, &result, sizeof(respond_msgbuf) - sizeof(long),
getpid(), 0) == -1)
syserr("msgrcv: While receiving result.");
switch(action) {
case '+':
fprintf(stdlog, "INFO: Return code: %d.\n", (int) result.code);
return result.code;
case '-':
fprintf(stdlog, "INFO: Return code: %d.\n", (int) result.code);
return result.code;
case 'H':
fprintf(stdout, "H %d\n", (int) result.code);
if(result.code == 0)
return 1;
else
return 0;
default:
fatal("Internal error.");
}
return 0;
}
