xref: /minix3/minix/servers/ds/main.c (revision 433d6423c39e34ec4b79c950597bb2d236f886be)
1*433d6423SLionel Sambuc /* Data Store Server.
2*433d6423SLionel Sambuc  * This service implements a little publish/subscribe data store that is
3*433d6423SLionel Sambuc  * crucial for the system's fault tolerance. Components that require state
4*433d6423SLionel Sambuc  * can store it here, for later retrieval, e.g., after a crash and subsequent
5*433d6423SLionel Sambuc  * restart by the reincarnation server.
6*433d6423SLionel Sambuc  *
7*433d6423SLionel Sambuc  * Created:
8*433d6423SLionel Sambuc  *   Oct 19, 2005	by Jorrit N. Herder
9*433d6423SLionel Sambuc  */
10*433d6423SLionel Sambuc 
11*433d6423SLionel Sambuc #include "inc.h"	/* include master header file */
12*433d6423SLionel Sambuc #include <minix/endpoint.h>
13*433d6423SLionel Sambuc 
14*433d6423SLionel Sambuc /* Allocate space for the global variables. */
15*433d6423SLionel Sambuc static endpoint_t who_e;	/* caller's proc number */
16*433d6423SLionel Sambuc static int callnr;		/* system call number */
17*433d6423SLionel Sambuc 
18*433d6423SLionel Sambuc /* Declare some local functions. */
19*433d6423SLionel Sambuc static void get_work(message *m_ptr);
20*433d6423SLionel Sambuc static void reply(endpoint_t whom, message *m_ptr);
21*433d6423SLionel Sambuc 
22*433d6423SLionel Sambuc /* SEF functions and variables. */
23*433d6423SLionel Sambuc static void sef_local_startup(void);
24*433d6423SLionel Sambuc 
25*433d6423SLionel Sambuc /*===========================================================================*
26*433d6423SLionel Sambuc  *				main                                         *
27*433d6423SLionel Sambuc  *===========================================================================*/
28*433d6423SLionel Sambuc int main(int argc, char **argv)
29*433d6423SLionel Sambuc {
30*433d6423SLionel Sambuc /* This is the main routine of this service. The main loop consists of
31*433d6423SLionel Sambuc  * three major activities: getting new work, processing the work, and
32*433d6423SLionel Sambuc  * sending the reply. The loop never terminates, unless a panic occurs.
33*433d6423SLionel Sambuc  */
34*433d6423SLionel Sambuc   message m;
35*433d6423SLionel Sambuc   int result;
36*433d6423SLionel Sambuc 
37*433d6423SLionel Sambuc   /* SEF local startup. */
38*433d6423SLionel Sambuc   env_setargs(argc, argv);
39*433d6423SLionel Sambuc   sef_local_startup();
40*433d6423SLionel Sambuc 
41*433d6423SLionel Sambuc   /* Main loop - get work and do it, forever. */
42*433d6423SLionel Sambuc   while (TRUE) {
43*433d6423SLionel Sambuc 
44*433d6423SLionel Sambuc       /* Wait for incoming message, sets 'callnr' and 'who'. */
45*433d6423SLionel Sambuc       get_work(&m);
46*433d6423SLionel Sambuc 
47*433d6423SLionel Sambuc       if (is_notify(callnr)) {
48*433d6423SLionel Sambuc           printf("DS: warning, got illegal notify from: %d\n", m.m_source);
49*433d6423SLionel Sambuc           result = EINVAL;
50*433d6423SLionel Sambuc           goto send_reply;
51*433d6423SLionel Sambuc       }
52*433d6423SLionel Sambuc 
53*433d6423SLionel Sambuc       switch (callnr) {
54*433d6423SLionel Sambuc       case DS_PUBLISH:
55*433d6423SLionel Sambuc           result = do_publish(&m);
56*433d6423SLionel Sambuc           break;
57*433d6423SLionel Sambuc       case DS_RETRIEVE:
58*433d6423SLionel Sambuc 	  result = do_retrieve(&m);
59*433d6423SLionel Sambuc 	  break;
60*433d6423SLionel Sambuc       case DS_RETRIEVE_LABEL:
61*433d6423SLionel Sambuc 	  result = do_retrieve_label(&m);
62*433d6423SLionel Sambuc 	  break;
63*433d6423SLionel Sambuc       case DS_DELETE:
64*433d6423SLionel Sambuc 	  result = do_delete(&m);
65*433d6423SLionel Sambuc 	  break;
66*433d6423SLionel Sambuc       case DS_SUBSCRIBE:
67*433d6423SLionel Sambuc 	  result = do_subscribe(&m);
68*433d6423SLionel Sambuc 	  break;
69*433d6423SLionel Sambuc       case DS_CHECK:
70*433d6423SLionel Sambuc 	  result = do_check(&m);
71*433d6423SLionel Sambuc 	  break;
72*433d6423SLionel Sambuc       case DS_GETSYSINFO:
73*433d6423SLionel Sambuc 	  result = do_getsysinfo(&m);
74*433d6423SLionel Sambuc 	  break;
75*433d6423SLionel Sambuc       default:
76*433d6423SLionel Sambuc           printf("DS: warning, got illegal request from %d\n", m.m_source);
77*433d6423SLionel Sambuc           result = EINVAL;
78*433d6423SLionel Sambuc       }
79*433d6423SLionel Sambuc 
80*433d6423SLionel Sambuc send_reply:
81*433d6423SLionel Sambuc       /* Finally send reply message, unless disabled. */
82*433d6423SLionel Sambuc       if (result != EDONTREPLY) {
83*433d6423SLionel Sambuc           m.m_type = result;  		/* build reply message */
84*433d6423SLionel Sambuc 	  reply(who_e, &m);		/* send it away */
85*433d6423SLionel Sambuc       }
86*433d6423SLionel Sambuc   }
87*433d6423SLionel Sambuc   return(OK);				/* shouldn't come here */
88*433d6423SLionel Sambuc }
89*433d6423SLionel Sambuc 
90*433d6423SLionel Sambuc /*===========================================================================*
91*433d6423SLionel Sambuc  *			       sef_local_startup			     *
92*433d6423SLionel Sambuc  *===========================================================================*/
93*433d6423SLionel Sambuc static void sef_local_startup()
94*433d6423SLionel Sambuc {
95*433d6423SLionel Sambuc   /* Register init callbacks. */
96*433d6423SLionel Sambuc   sef_setcb_init_fresh(sef_cb_init_fresh);
97*433d6423SLionel Sambuc   sef_setcb_init_restart(sef_cb_init_fail);
98*433d6423SLionel Sambuc 
99*433d6423SLionel Sambuc   /* No live update support for now. */
100*433d6423SLionel Sambuc 
101*433d6423SLionel Sambuc   /* Let SEF perform startup. */
102*433d6423SLionel Sambuc   sef_startup();
103*433d6423SLionel Sambuc }
104*433d6423SLionel Sambuc 
105*433d6423SLionel Sambuc /*===========================================================================*
106*433d6423SLionel Sambuc  *				get_work                                     *
107*433d6423SLionel Sambuc  *===========================================================================*/
108*433d6423SLionel Sambuc static void get_work(
109*433d6423SLionel Sambuc   message *m_ptr			/* message buffer */
110*433d6423SLionel Sambuc )
111*433d6423SLionel Sambuc {
112*433d6423SLionel Sambuc     int status = sef_receive(ANY, m_ptr);   /* blocks until message arrives */
113*433d6423SLionel Sambuc     if (OK != status)
114*433d6423SLionel Sambuc         panic("failed to receive message!: %d", status);
115*433d6423SLionel Sambuc     who_e = m_ptr->m_source;        /* message arrived! set sender */
116*433d6423SLionel Sambuc     callnr = m_ptr->m_type;       /* set function call number */
117*433d6423SLionel Sambuc }
118*433d6423SLionel Sambuc 
119*433d6423SLionel Sambuc /*===========================================================================*
120*433d6423SLionel Sambuc  *				reply					     *
121*433d6423SLionel Sambuc  *===========================================================================*/
122*433d6423SLionel Sambuc static void reply(
123*433d6423SLionel Sambuc   endpoint_t who_e,			/* destination */
124*433d6423SLionel Sambuc   message *m_ptr			/* message buffer */
125*433d6423SLionel Sambuc )
126*433d6423SLionel Sambuc {
127*433d6423SLionel Sambuc     int s = ipc_send(who_e, m_ptr);    /* send the message */
128*433d6423SLionel Sambuc     if (OK != s)
129*433d6423SLionel Sambuc         printf("DS: unable to send reply to %d: %d\n", who_e, s);
130*433d6423SLionel Sambuc }
131*433d6423SLionel Sambuc 
132