citadel/housekeeping.c

   1 /*
   2  * $Id$
   3  *
   4  * This file contains housekeeping tasks which periodically
   5  * need to be executed.  It keeps a nice little queue...
   6  *
   7  */
   8
   9 #include "sysdep.h"
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12 #include <stdio.h>
  13 #include <fcntl.h>
  14 #include <time.h>
  15 #include <ctype.h>
  16 #include <string.h>
  17 #include <errno.h>
  18 #include <limits.h>
  19 #include <sys/types.h>
  20 #include <sys/time.h>
  21 #ifdef HAVE_SYS_SELECT_H
  22 #include <sys/select.h>
  23 #endif
  24 #include "tools.h"
  25 #include "citadel.h"
  26 #include "server.h"
  27 #include "citserver.h"
  28 #include "config.h"
  29 #include "housekeeping.h"
  30 #include "sysdep_decls.h"
  31 #include "room_ops.h"
  32 #include "database.h"
  33
  34
  35 int housepipe[2];       /* This is the queue for housekeeping tasks */
  36
  37
  38 /*
  39  * Terminate idle sessions.  This function pounds through the session table
  40  * comparing the current time to each session's time-of-last-command.  If an
  41  * idle session is found it is terminated, then the search restarts at the
  42  * beginning because the pointer to our place in the list becomes invalid.
  43  */
  44 void terminate_idle_sessions(void) {
  45         struct CitContext *ccptr;
  46         time_t now;
  47         int session_to_kill;
  48
  49         now = time(NULL);
  50         session_to_kill = 0;
  51         begin_critical_section(S_SESSION_TABLE);
  52         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
  53                 if (  (ccptr!=CC)
  54                 && (config.c_sleeping > 0)
  55                 && (now - (ccptr->lastcmd) > config.c_sleeping) ) {
  56                         ccptr->kill_me = 1;
  57                 }
  58         }
  59         end_critical_section(S_SESSION_TABLE);
  60 }
  61
  62
  63
  64 void check_sched_shutdown(void) {
  65         if ((ScheduledShutdown == 1) && (ContextList == NULL)) {
  66                 lprintf(3, "Scheduled shutdown initiating.\n");
  67                 master_cleanup();
  68         }
  69 }
  70
  71
  72
  73 /*
  74  * This is the main loop for the housekeeping thread.  It remains active
  75  * during the entire run of the server.
  76  */
  77 void housekeeping_loop(void) {
  78         long flags;
  79         struct timeval tv;
  80         fd_set readfds;
  81         int did_something;
  82         char house_cmd[256];    /* Housekeep cmds are always 256 bytes long */
  83         char cmd[256];
  84
  85         if (pipe(housepipe) != 0) {
  86                 lprintf(1, "FATAL ERROR: can't create housekeeping pipe: %s\n",
  87                         strerror(errno));
  88                 exit(0);
  89         }
  90
  91         flags = (long) fcntl(housepipe[1], F_GETFL);
  92         flags |= O_NONBLOCK;
  93         fcntl(housepipe[1], F_SETFL, flags);
  94
  95         while(1) {
  96                 do {
  97                         did_something = 0;
  98                         tv.tv_sec = HOUSEKEEPING_WAKEUP;
  99                         tv.tv_usec = 0;
 100                         FD_ZERO(&readfds);
 101                         FD_SET(housepipe[0], &readfds);
 102                         select(housepipe[0] + 1, &readfds, NULL, NULL, &tv);
 103                         if (FD_ISSET(housepipe[0], &readfds)) {
 104                                 did_something = 1;
 105                         }
 106
 107                         if (did_something) {
 108                                 read(housepipe[0], house_cmd, 256);
 109                         }
 110                         else {
 111                                 memset(house_cmd, 0, 256);
 112                                 strcpy(house_cmd, "MINUTE");
 113                         }
 114
 115                         extract(cmd, house_cmd, 0);
 116                         cdb_begin_transaction();
 117
 118                         /* Do whatever this cmd requires */
 119
 120                         /* Once-every-minute housekeeper */
 121                         if (!strcmp(cmd, "MINUTE")) {
 122                                 terminate_idle_sessions();
 123                         }
 124
 125                         /* Scheduled shutdown housekeeper */
 126                         else if (!strcmp(cmd, "SCHED_SHUTDOWN")) {
 127                                 check_sched_shutdown();
 128                         }
 129
 130                         /* Unknown */
 131                         else {
 132                                 lprintf(7, "Unknown housekeeping command\n");
 133                         }
 134
 135                         cdb_end_transaction();
 136
 137                 } while (did_something);
 138         }
 139 }
 140
 141
 142
 143
 144
 145
 146 void enter_housekeeping_cmd(char *cmd) {
 147         char cmdbuf[256];
 148
 149         lprintf(9, "enter_housekeeping_cmd(%s)\n", cmd);
 150         safestrncpy(cmdbuf, cmd, 256);
 151         begin_critical_section(S_HOUSEKEEPING);
 152         write(housepipe[1], cmdbuf, 256);
 153         end_critical_section(S_HOUSEKEEPING);
 154         lprintf(9, "leaving enter_housekeeping_cmd()\n");
 155 }
 156
 157
 158
 159 /*
 160  * Check (and fix) floor reference counts.  This doesn't need to be done
 161  * very often, since the counts should remain correct during normal operation.
 162  * NOTE: this function pair should ONLY be called during startup.  It is NOT
 163  * thread safe.
 164  */
 165 void check_ref_counts_backend(struct quickroom *qrbuf, void *data) {
 166         struct floor flbuf;
 167
 168         getfloor(&flbuf, qrbuf->QRfloor);
 169         ++flbuf.f_ref_count;
 170         flbuf.f_flags = flbuf.f_flags | QR_INUSE;
 171         putfloor(&flbuf, qrbuf->QRfloor);
 172 }
 173
 174 void check_ref_counts(void) {
 175         struct floor flbuf;
 176         int a;
 177
 178         lprintf(7, "Checking floor reference counts\n");
 179         for (a=0; a<MAXFLOORS; ++a) {
 180                 lprintf(9, "Resetting floor %d\n", a);
 181                 getfloor(&flbuf, a);
 182                 flbuf.f_ref_count = 0;
 183                 flbuf.f_flags = flbuf.f_flags & ~QR_INUSE;
 184                 putfloor(&flbuf, a);
 185         }
 186
 187         ForEachRoom(check_ref_counts_backend, NULL);
 188 }
 189