Ace code example: a small program that implements Computer Network Timing

Text/Jiang Tao

Application description

 

This code implements the RFC 868 client. Start the program and establish a TCP connection to the given time service. The time service returns a four-byte integer, which is the number of seconds from on January 1, January 1, 1900 to the past time, of course, it is in the order of network bytes. After the network bytes are converted to host bytes, we can read this number.

Currently, this program only supports windows. Because the modification time in Linux is inconsistent with that in Windows, you can modify the code on your own.

 

 

// Timeclient. cpp
// Platform: Win32

# Include "ACE/log_msg.h"
# Include "ACE/time_value.h"
# Include "ACE/OS. H"
# Include "ACE/date_time.h"
# Include "ACE/streams. H"
# Include "ACE/inet_addr.h"
# Include "ACE/sock_connector.h"
# Include "ACE/sock_stream.h"
# Include "ACE/get_opt.h"
# Include <string>
Using namespace STD;
# Ifdef Win32
# Include <windows. h>
# Endif
# If 0
// Some available server addresses
# Define numsrv 15
Char * serv_ip [numsrv] = {"64.236.96.53",/* nist1.aol-va.truetime.com */
"128.138.140.44",/* utcnist.colorado.edu */
"207.200.81.113",/* nist1.aol-ca.truetime.com */
"216.200.93.8",/* nist1-dc.glassey.com */
"63.149.208.50",/* nist1.datum.com */
"208.184.49.9",/* nist1-ny.glassey.com */
"207.126.103.204",/* nist1-sj.glassey.com */
"129.6.15.28",/* time-a.nist.gov */
"129.6.15.29",/* time-b.nist.gov */
"132133.4.101",/* time-a.timefreq.bldrdoc.gov */
"132133.4.102",/* time-b.timefreq.bldrdoc.gov */
"132133.4.103",/* time-c.timefreq.bldrdoc.gov */
"192.43.244.18",/* time.nist.gov */
"131.107.1.10",/* time-nw.nist.gov */
"Utcnist.colorado.edu"/* DNS entry = 128.138.140.44 */
};
# Endif

# Ifdef Win32
Void timettosystemtime (time_t T, lpsystemtime PST)
{
Filetime ft;
Longlong LL = int32x32to64 (T, 10000000) + 116444736000000000;
Ft. dwlowdatetime = (DWORD) ll;
Ft. dwhighdatetime = (DWORD) (LL> 32 );

Filetimetosystemtime (& ft, Pst );
}

Int setsystetime (const time_t & T)
{
Systemtime st;
Memset (& St, 0, sizeof (ST ));
Timettosystemtime (T, & St );
If (: setsystemtime (& St ))
{
: Sendmessage (hwnd_broadcast, wm_timechange, 0, 0 );
Return 0;
}
Return-1;

}
# Endif
Int ace_tmain (INT argc, ace_tchar * argv [])
{
Ace_sock_stream peer;
Ace_sock_connector conn;
Ace_uint32 tempvalue = 0;
Ace_inet_addr address;
// (37 ,);
String Server = "nist1-la.ustiming.org ";
Ace_get_opt get_opts (argc, argv, ace_lib_text ("s :? "));
Int ich;
While (ICH = get_opts ())! = EOF ){
Switch (ICH ){
Case/'s/':/* u specifies that UDP shoshould be used */
Server = get_opts.opt_arg ();
Break;
Case /'? /':/* T specifies that zero copy read shocould be used */
Cout <"Usage: timeclient-S //" nist1-la.ustiming.org // "" <Endl;
Return-1;

Default:/* no parameters */
Break;
}
}

Address. Set (37, server. c_str ());

If (-1 = conn. Connect (peer, address ))
{
Ace_error_return (lm_error,
"% P ",
"Connect"),-1 );
}
Ssize_t n = peer. Recv (char *) & tempvalue, 4 );
If (n> 0)
{
// Convert bytes from network to host

Tempvalue = ntohl (tempvalue );
Tempvalue-= 2208988800l; // * subtract 1970.0-1900.0 */
Time_t T (tempvalue );
If (setsystetime (t) = 0)
{
Cout <"adjtime OK." <Endl;
}
Else
{
Cout <"adjtime error" <Endl;
}
}

Peer. Close ();

Time_t lt;
Lt = Time (null );
Char * Ss = ctime (& lt );
Cout <"the system time" <SS <Endl;
Return 0;
};