1 /* $NetBSD: statd.h,v 1.1 1997/03/10 06:28:32 scottr Exp $ */ 2 3 /* 4 * Copyright (c) 1995 5 * A.R. Gordon (andrew.gordon@net-tel.co.uk). All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed for the FreeBSD project 18 * 4. Neither the name of the author nor the names of any co-contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY ANDREW GORDON AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 */ 35 36 #include "sm_inter.h" 37 38 /* ------------------------------------------------------------------------- */ 39 /* 40 * Data structures for recording monitored hosts 41 * 42 * The information held by the status monitor comprises a list of hosts 43 * that we have been asked to monitor, and, associated with each monitored 44 * host, one or more clients to be called back if the monitored host crashes. 45 * 46 * The list of monitored hosts must be retained over a crash, so that upon 47 * re-boot we can call the SM_NOTIFY procedure in all those hosts so as to 48 * cause them to start recovery processing. On the other hand, the client 49 * call-backs are not required to be preserved: they are assumed (in the 50 * protocol design) to be local processes which will have crashed when 51 * we did, and so are discarded on restart. 52 * 53 * We handle this by keeping the list of monitored hosts in a file 54 * (/var/statd.state) which is mmap()ed and whose format is described 55 * by the typedef FileLayout. The lists of client callbacks are chained 56 * off this structure, but are held in normal memory and so will be 57 * lost after a re-boot. Hence the actual values of MonList * pointers 58 * in the copy on disc have no significance, but their NULL/non-NULL 59 * status indicates whether this host is actually being monitored or if it 60 * is an empty slot in the file. 61 */ 62 63 typedef struct MonList_s { 64 struct MonList_s *next; /* Next in list or NULL */ 65 char notifyHost[SM_MAXSTRLEN + 1]; /* Host to notify */ 66 int notifyProg; /* RPC program number to call */ 67 int notifyVers; /* version number */ 68 int notifyProc; /* procedure number */ 69 u_char notifyData[16]; /* Opaque data from caller */ 70 } MonList; 71 72 typedef struct { 73 char hostname[SM_MAXSTRLEN + 1]; /* Name of monitored host */ 74 int notifyReqd; /* TRUE if we've crashed and not yet 75 informed the monitored host */ 76 MonList *monList; /* List of clients to inform if we 77 hear that the monitored host has 78 crashed, NULL if no longer monitored */ 79 } HostInfo; 80 81 82 /* Overall file layout. */ 83 84 typedef struct { 85 int ourState; /* State number as defined in statd protocol */ 86 int noOfHosts; /* Number of elements in hosts[] */ 87 char reserved[248]; /* Reserved for future use */ 88 HostInfo hosts[1]; /* vector of monitored hosts */ 89 } FileLayout; 90 #define HEADER_LEN (sizeof(FileLayout) - sizeof(HostInfo)) 91 92 /* ------------------------------------------------------------------------- */ 93 94 /* Global variables */ 95 96 extern FileLayout *status_info; /* The mmap()ed status file */ 97 extern int debug; /* = 1 to enable diagnostics to syslog */ 98 99 /* Function prototypes */ 100 101 extern HostInfo *find_host __P((char *hostname, int create)); 102 extern void init_file __P((char *filename)); 103 extern void notify_hosts __P((void)); 104 extern void sync_file __P((void)); 105