167 lines
5.1 KiB
C
167 lines
5.1 KiB
C
/* Data Store Server.
|
|
* This service implements a little publish/subscribe data store that is
|
|
* crucial for the system's fault tolerance. Components that require state
|
|
* can store it here, for later retrieval, e.g., after a crash and subsequent
|
|
* restart by the reincarnation server.
|
|
*
|
|
* Created:
|
|
* Oct 19, 2005 by Jorrit N. Herder
|
|
*/
|
|
|
|
#include "inc.h" /* include master header file */
|
|
#include <minix/endpoint.h>
|
|
|
|
/* Allocate space for the global variables. */
|
|
endpoint_t who_e; /* caller's proc number */
|
|
int callnr; /* system call number */
|
|
int sys_panic; /* flag to indicate system-wide panic */
|
|
|
|
extern int errno; /* error number set by system library */
|
|
|
|
/* Declare some local functions. */
|
|
FORWARD _PROTOTYPE(void exit_server, (void) );
|
|
FORWARD _PROTOTYPE(void sig_handler, (void) );
|
|
FORWARD _PROTOTYPE(void get_work, (message *m_ptr) );
|
|
FORWARD _PROTOTYPE(void reply, (int whom, message *m_ptr) );
|
|
|
|
/* SEF functions and variables. */
|
|
FORWARD _PROTOTYPE( void sef_local_startup, (void) );
|
|
|
|
/*===========================================================================*
|
|
* main *
|
|
*===========================================================================*/
|
|
PUBLIC int main(int argc, char **argv)
|
|
{
|
|
/* This is the main routine of this service. The main loop consists of
|
|
* three major activities: getting new work, processing the work, and
|
|
* sending the reply. The loop never terminates, unless a panic occurs.
|
|
*/
|
|
message m;
|
|
int result;
|
|
|
|
/* SEF local startup. */
|
|
env_setargs(argc, argv);
|
|
sef_local_startup();
|
|
|
|
/* Main loop - get work and do it, forever. */
|
|
while (TRUE) {
|
|
|
|
/* Wait for incoming message, sets 'callnr' and 'who'. */
|
|
get_work(&m);
|
|
|
|
if (is_notify(callnr)) {
|
|
switch (_ENDPOINT_P(who_e)) {
|
|
case PM_PROC_NR:
|
|
sig_handler();
|
|
break;
|
|
default:
|
|
report("DS","warning, got illegal notify from:",
|
|
m.m_source);
|
|
result = EINVAL;
|
|
goto send_reply;
|
|
}
|
|
|
|
/* done, get a new message */
|
|
}
|
|
|
|
switch (callnr) {
|
|
case DS_PUBLISH:
|
|
result = do_publish(&m);
|
|
break;
|
|
case DS_RETRIEVE:
|
|
result = do_retrieve(&m);
|
|
break;
|
|
case DS_SUBSCRIBE:
|
|
result = do_subscribe(&m);
|
|
break;
|
|
case DS_CHECK:
|
|
result = do_check(&m);
|
|
break;
|
|
case GETSYSINFO:
|
|
result = do_getsysinfo(&m);
|
|
break;
|
|
default:
|
|
report("DS","warning, got illegal request from:", m.m_source);
|
|
result = EINVAL;
|
|
}
|
|
|
|
send_reply:
|
|
/* Finally send reply message, unless disabled. */
|
|
if (result != EDONTREPLY) {
|
|
m.m_type = result; /* build reply message */
|
|
reply(who_e, &m); /* send it away */
|
|
}
|
|
}
|
|
return(OK); /* shouldn't come here */
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* sef_local_startup *
|
|
*===========================================================================*/
|
|
PRIVATE void sef_local_startup()
|
|
{
|
|
/* Register init callbacks. */
|
|
sef_setcb_init_fresh(sef_cb_init_fresh);
|
|
sef_setcb_init_restart(sef_cb_init_restart_fail);
|
|
|
|
/* No live update support for now. */
|
|
|
|
/* Let SEF perform startup. */
|
|
sef_startup();
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* sig_handler *
|
|
*===========================================================================*/
|
|
PRIVATE void sig_handler()
|
|
{
|
|
/* Signal handler. */
|
|
sigset_t sigset;
|
|
|
|
/* Try to obtain signal set from PM. */
|
|
if (getsigset(&sigset) != 0) return;
|
|
|
|
/* Check for known signals. */
|
|
if (sigismember(&sigset, SIGTERM)) {
|
|
exit_server();
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* exit_server *
|
|
*===========================================================================*/
|
|
PRIVATE void exit_server()
|
|
{
|
|
/* Shut down the information service. */
|
|
|
|
/* Done. Now exit. */
|
|
exit(0);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* get_work *
|
|
*===========================================================================*/
|
|
PRIVATE void get_work(m_ptr)
|
|
message *m_ptr; /* message buffer */
|
|
{
|
|
int status = 0;
|
|
status = sef_receive(ANY, m_ptr); /* this blocks until message arrives */
|
|
if (OK != status)
|
|
panic("DS","failed to receive message!", status);
|
|
who_e = m_ptr->m_source; /* message arrived! set sender */
|
|
callnr = m_ptr->m_type; /* set function call number */
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* reply *
|
|
*===========================================================================*/
|
|
PRIVATE void reply(who_e, m_ptr)
|
|
int who_e; /* destination */
|
|
message *m_ptr; /* message buffer */
|
|
{
|
|
int s;
|
|
s = send(who_e, m_ptr); /* send the message */
|
|
if (OK != s)
|
|
printf("DS: unable to send reply to %d: %d\n", who_e, s);
|
|
}
|
|
|