Added and changed program locks

lib/Makefile

@@ -8,12 +8,12 @@ CLCOMM_SRCS	= clcomm.c client.c crc.c semafore.c signame.c
 CLCOMM_OBJS	= clcomm.o client.o crc.o semafore.o signame.o
 CLCOMM_HDRS	= clcomm.h
 COMMON_SRCS	= attach.c falists.c hdr.c parsedate.c rfcmsg.c unpacker.c \
-		  batchrd.c ftn.c pktname.c mangle.c sectest.c \
+		  batchrd.c ftn.c pktname.c mangle.c sectest.c proglock.c \
 		  dostran.c ftnmsg.c mbfile.c nodelock.c rawio.c strcasestr.c \
 		  execute.c expipe.c getheader.c noderecord.c rfcaddr.c strutil.c \
 		  faddr.c gmtoffset.c packet.c rfcdate.c term.c endian.c
 COMMON_OBJS	= ftscprod.o attach.o falists.o hdr.o parsedate.o rfcmsg.o unpacker.o \
-		  batchrd.o ftn.o pktname.o mangle.o sectest.o \
+		  batchrd.o ftn.o pktname.o mangle.o sectest.o proglock.o \
 		  dostran.o ftnmsg.o mbfile.o nodelock.o rawio.o strcasestr.o \
 		  execute.o expipe.o getheader.o noderecord.o rfcaddr.o strutil.o \
 		  faddr.o gmtoffset.o packet.o rfcdate.o term.o endian.o

lib/common.h

@@ -508,5 +508,12 @@ void	name_mangle(char *);	    /* Mangle name or make uppercase	*/
 int  Access(securityrec, securityrec);  /* Check security access	*/
 int  Le_Access(securityrec, securityrec);  /* Endian independant	*/
 
+
+/*
+ * proglock.c
+ */
+int lockprogram(char *);	    /* Lock a program			*/
+void ulockprogram(char *);	    /* Unlock a program			*/
+
 #endif
 

lib/proglock.c

@@ -0,0 +1,150 @@
+/*****************************************************************************
+ *
+ * $Id$
+ * Purpose ...............: Program Locking
+ *
+ *****************************************************************************
+ * Copyright (C) 1997-2003
+ *   
+ * Michiel Broek		FIDO:		2:280/2802
+ * Beekmansbos 10
+ * 1971 BV IJmuiden
+ * the Netherlands
+ *
+ * This file is part of MBSE BBS.
+ *
+ * This BBS is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * MBSE BBS is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with MBSE BBS; see the file COPYING.  If not, write to the Free
+ * Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ *****************************************************************************/
+
+#include "../config.h"
+#include "../lib/libs.h"
+//#include "../lib/memwatch.h"
+#include "../lib/structs.h"
+#include "../lib/users.h"
+#include "../lib/records.h"
+#include "../lib/common.h"
+#include "../lib/clcomm.h"
+//#include "../lib/dbcfg.h"
+//#include "../lib/dbftn.h"
+//#include "../lib/mberrors.h"
+
+
+extern		int do_quiet;		/* Quiet flag			    */
+
+
+/*
+ *  Put a lock on a program.
+ */
+int lockprogram(char *progname)
+{
+    char    *tempfile, *lockfile;
+    FILE    *fp;
+    pid_t   oldpid;
+
+    tempfile  = calloc(PATH_MAX, sizeof(char));
+    lockfile = calloc(PATH_MAX, sizeof(char));
+
+    sprintf(tempfile, "%s/var/run/%s.tmp", getenv("MBSE_ROOT"), progname);
+    sprintf(lockfile, "%s/var/run/%s", getenv("MBSE_ROOT"), progname);
+
+    if ((fp = fopen(tempfile, "w")) == NULL) {
+	WriteError("$Can't create lockfile \"%s\"", tempfile);
+	free(tempfile);
+	free(lockfile);
+	return 1;
+    }
+    fprintf(fp, "%10u\n", getpid());
+    fclose(fp);
+
+    while (TRUE) {
+	if (link(tempfile, lockfile) == 0) {
+	    unlink(tempfile);
+	    free(tempfile);
+	    free(lockfile);
+	    return 0;
+	}
+	if ((fp = fopen(lockfile, "r")) == NULL) {
+	    WriteError("$Can't open lockfile \"%s\"", lockfile);
+	    unlink(tempfile);
+	    free(tempfile);
+	    free(lockfile);
+	    return 1;
+	}
+	if (fscanf(fp, "%u", &oldpid) != 1) {
+	    WriteError("$Can't read old pid from \"%s\"", tempfile);
+	    fclose(fp);
+	    unlink(tempfile);
+	    free(tempfile);
+	    free(lockfile);
+	    return 1;
+	}
+	fclose(fp);
+	if (kill(oldpid,0) == -1) {
+	    if (errno == ESRCH) {
+		Syslog('+', "Stale lock found for pid %u", oldpid);
+		unlink(lockfile);
+		/* no return, try lock again */  
+	    } else {
+		WriteError("$Kill for %u failed", oldpid);
+		unlink(tempfile);
+		free(tempfile);
+		free(lockfile);
+		return 1;
+	    }
+	} else {
+	    Syslog('+', "%s already running, pid=%u", progname, oldpid);
+	    if (!do_quiet)
+		printf("Another %s is already running.\n", progname);
+	    unlink(tempfile);
+	    free(tempfile);
+	    free(lockfile);
+	    return 1;
+	}
+    }
+}
+
+
+
+void ulockprogram(char *progname)
+{
+    char    *lockfile;
+    FILE    *fp;
+    pid_t   oldpid;
+
+    lockfile = calloc(PATH_MAX, sizeof(char));
+    sprintf(lockfile, "%s/var/run/%s", getenv("MBSE_ROOT"), progname);
+
+    if ((fp = fopen(lockfile, "r")) == NULL) {
+	WriteError("$Can't open lockfile \"%s\"", lockfile);
+	free(lockfile);
+	return;
+    }
+    if (fscanf(fp, "%u", &oldpid) != 1) {
+	WriteError("$Can't read old pid from \"%s\"", lockfile);
+	fclose(fp);
+	unlink(lockfile);
+	free(lockfile);
+	return;
+    }
+
+    if (oldpid == getpid()) {
+	(void)unlink(lockfile);
+    } else {
+	WriteError("Lockfile owned by pid %d, not removed", oldpid);
+    }
+
+    free(lockfile);
+}
+