servers/is/main.c

   1 /* System Information Service.
   2  * This service handles the various debugging dumps, such as the process
   3  * table, so that these no longer directly touch kernel memory. Instead, the
   4  * system task is asked to copy some table in local memory.
   5  *
   6  * Created:
   7  *   Apr 29, 2004       by Jorrit N. Herder
   8  */
   9
  10 #include "inc.h"
  11
  12 /* Set debugging level to 0, 1, or 2 to see no, some, all debug output. */
  13 #define DEBUG_LEVEL     1
  14 #define DPRINTF         if (DEBUG_LEVEL > 0) printf
  15
  16 /* Allocate space for the global variables. */
  17 message m_in;           /* the input message itself */
  18 message m_out;          /* the output message used for reply */
  19 int who_e;              /* caller's proc number */
  20 int callnr;             /* system call number */
  21
  22 extern int errno;       /* error number set by system library */
  23
  24 /* Declare some local functions. */
  25 FORWARD _PROTOTYPE(void init_server, (int argc, char **argv)            );
  26 FORWARD _PROTOTYPE(void sig_handler, (void)                             );
  27 FORWARD _PROTOTYPE(void exit_server, (void)                             );
  28 FORWARD _PROTOTYPE(void get_work, (void)                                );
  29 FORWARD _PROTOTYPE(void reply, (int whom, int result)                   );
  30
  31 /*===========================================================================*
  32  *                              main                                         *
  33  *===========================================================================*/
  34 PUBLIC int main(int argc, char **argv)
  35 {
  36 /* This is the main routine of this service. The main loop consists of
  37  * three major activities: getting new work, processing the work, and
  38  * sending the reply. The loop never terminates, unless a panic occurs.
  39  */
  40   int result;
  41   sigset_t sigset;
  42
  43   /* Initialize the server, then go to work. */
  44   init_server(argc, argv);
  45
  46   /* Main loop - get work and do it, forever. */
  47   while (TRUE) {
  48
  49       /* Wait for incoming message, sets 'callnr' and 'who'. */
  50       get_work();
  51
  52       switch (callnr) {
  53       case SYS_SIG:
  54           printf("got SYS_SIG message\n");
  55           sigset = m_in.NOTIFY_ARG;
  56           for ( result=0; result< _NSIG; result++) {
  57               if (sigismember(&sigset, result))
  58                   printf("signal %d found\n", result);
  59           }
  60           continue;
  61       case PROC_EVENT:
  62           sig_handler();
  63           continue;
  64       case FKEY_PRESSED:
  65           result = do_fkey_pressed(&m_in);
  66           break;
  67       case DEV_PING:
  68           notify(m_in.m_source);
  69           continue;
  70       default:
  71           report("IS","warning, got illegal request from:", m_in.m_source);
  72           result = EINVAL;
  73       }
  74
  75       /* Finally send reply message, unless disabled. */
  76       if (result != EDONTREPLY) {
  77           reply(who_e, result);
  78       }
  79   }
  80   return(OK);                           /* shouldn't come here */
  81 }
  82
  83 /*===========================================================================*
  84  *                               init_server                                 *
  85  *===========================================================================*/
  86 PRIVATE void init_server(int argc, char **argv)
  87 {
  88 /* Initialize the information service. */
  89   int fkeys, sfkeys;
  90   int i, s;
  91   struct sigaction sigact;
  92
  93   /* Install signal handler. Ask PM to transform signal into message. */
  94   sigact.sa_handler = SIG_MESS;
  95   sigact.sa_mask = ~0;                  /* block all other signals */
  96   sigact.sa_flags = 0;                  /* default behaviour */
  97   if (sigaction(SIGTERM, &sigact, NULL) < 0)
  98       report("IS","warning, sigaction() failed", errno);
  99
 100   /* Set key mappings. IS takes all of F1-F12 and Shift+F1-F6. */
 101   fkeys = sfkeys = 0;
 102   for (i=1; i<=12; i++) bit_set(fkeys, i);
 103   for (i=1; i<= 8; i++) bit_set(sfkeys, i);
 104   if ((s=fkey_map(&fkeys, &sfkeys)) != OK)
 105       report("IS", "warning, fkey_map failed:", s);
 106 }
 107
 108 /*===========================================================================*
 109  *                              sig_handler                                  *
 110  *===========================================================================*/
 111 PRIVATE void sig_handler()
 112 {
 113   sigset_t sigset;
 114   int sig;
 115
 116   /* Try to obtain signal set from PM. */
 117   if (getsigset(&sigset) != 0) return;
 118
 119   /* Check for known signals. */
 120   if (sigismember(&sigset, SIGTERM)) {
 121       exit_server();
 122   }
 123 }
 124
 125 /*===========================================================================*
 126  *                              exit_server                                  *
 127  *===========================================================================*/
 128 PRIVATE void exit_server()
 129 {
 130 /* Shut down the information service. */
 131   int fkeys, sfkeys;
 132   int i,s;
 133
 134   /* Release the function key mappings requested in init_server().
 135    * IS took all of F1-F12 and Shift+F1-F6.
 136    */
 137   fkeys = sfkeys = 0;
 138   for (i=1; i<=12; i++) bit_set(fkeys, i);
 139   for (i=1; i<= 7; i++) bit_set(sfkeys, i);
 140   if ((s=fkey_unmap(&fkeys, &sfkeys)) != OK)
 141       report("IS", "warning, unfkey_map failed:", s);
 142
 143   /* Done. Now exit. */
 144   exit(0);
 145 }
 146
 147 /*===========================================================================*
 148  *                              get_work                                     *
 149  *===========================================================================*/
 150 PRIVATE void get_work()
 151 {
 152     int status = 0;
 153     status = receive(ANY, &m_in);   /* this blocks until message arrives */
 154     if (OK != status)
 155         panic("IS","failed to receive message!", status);
 156     who_e = m_in.m_source;        /* message arrived! set sender */
 157     callnr = m_in.m_type;       /* set function call number */
 158 }
 159
 160 /*===========================================================================*
 161  *                              reply                                        *
 162  *===========================================================================*/
 163 PRIVATE void reply(who, result)
 164 int who;                                /* destination */
 165 int result;                             /* report result to replyee */
 166 {
 167     int send_status;
 168     m_out.m_type = result;              /* build reply message */
 169     send_status = send(who, &m_out);    /* send the message */
 170     if (OK != send_status)
 171         panic("IS", "unable to send reply!", send_status);
 172 }
 173