add -d flag for reporting active sessions at a specified point in time.

2 files changed, 178 insertions, 12 deletions

diff --git a/usr.bin/last/last.1 b/usr.bin/last/last.1
index eff134f1885..07708ea3a9c 100644
--- a/usr.bin/last/last.1
+++ b/usr.bin/last/last.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: last.1,v 1.2 1996/06/26 05:34:51 deraadt Exp $
+.\"	$OpenBSD: last.1,v 1.3 1997/07/20 07:54:08 jdm Exp $
 .\"	$NetBSD: last.1,v 1.3 1994/12/21 22:41:23 jtc Exp $
 .\"
 .\" Copyright (c) 1980, 1990, 1993
@@ -46,14 +46,17 @@
 .Op Fl f Ar file
 .Op Fl h Ar host
 .Op Fl t Ar tty
+.Op Fl d Ar [[CC]YY][MMDD]hhmm[.SS]
 .Op user ...
 .Sh DESCRIPTION
 .Nm Last
-will list the sessions of specified
+will either (1) list the sessions of specified
 .Ar users ,
 .Ar ttys ,
 and
-.Ar hosts ,
+.Ar hosts , 
+in reverse time order, 
+or (2) list the users logged in at a specified snapshot date & time
 in reverse time order.  Each line of output contains
 the user name, the tty from which the session was conducted, any
 hostname, the start and stop times for the session, and the duration
@@ -84,10 +87,65 @@ equivalent to
 .It Fl h Ar host
 .Ar Host
 names may be names or internet numbers.
+.It Fl d Ar date
+Specify the snapshot date & time.  
+All users logged in at the snapshot date & time will
+be reported.
+This may be used with the 
+.Ar -f file
+option to derive the results from stored wtmp files.
+When this argument is provided, all other options except for
+.Ar -f file 
+and 
+.Ar -n
+are ignored.
+The argument should be in the form
+.Dq [[CC]YY][MMDD]hhmm[.SS]
+where each pair of letters represents the following:
+.Pp
+.Bl -tag -width Ds -compact -offset indent
+.It Ar CC
+The first two digits of the year (the century).
+.It Ar YY
+The second two digits of the year.
+If
+.Dq YY
+is specified, but
+.Dq CC
+is not, a value for
+.Dq YY
+between 69 and 99 results in a
+.Dq YY
+value of 19.
+Otherwise, a
+.Dq YY
+value of 20 is used.
+.It Ar MM
+The month of the year, from 1 to 12.
+.It Ar DD
+the day of the month, from 1 to 31.
+.It Ar hh
+The hour of the day, from 0 to 23.
+.It Ar mm
+The minute of the hour, from 0 to 59.
+.It Ar SS
+The second of the minute, from 0 to 61.
+.El
+.Pp
+If the
+.Dq CC
+and
+.Dq YY
+letter pairs are not specified, the values default to the current
+year.
+If the
+.Dq SS
+letter pair is not specified, the value defaults to 0.
 .El
 .Pp
 If
-multiple arguments are given, the information which applies to any of the
+multiple arguments are given, and a snapshot time is not specified, the
+information which applies to any of the
 arguments is printed, e.g.,
 .Dq Li "last root -t console"
 would list all of
diff --git a/usr.bin/last/last.c b/usr.bin/last/last.c
index 5c425dd4d80..de149a0f113 100644
--- a/usr.bin/last/last.c
+++ b/usr.bin/last/last.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: last.c,v 1.3 1997/01/15 23:42:41 millert Exp $	*/
+/*	$OpenBSD: last.c,v 1.4 1997/07/20 07:54:09 jdm Exp $	*/
 /*	$NetBSD: last.c,v 1.6 1994/12/24 16:49:02 cgd Exp $	*/
 
 /*
@@ -44,7 +44,7 @@ static char copyright[] =
 #if 0
 static char sccsid[] = "@(#)last.c	8.2 (Berkeley) 4/2/94";
 #endif
-static char rcsid[] = "$OpenBSD: last.c,v 1.3 1997/01/15 23:42:41 millert Exp $";
+static char rcsid[] = "$OpenBSD: last.c,v 1.4 1997/07/20 07:54:09 jdm Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -64,6 +64,7 @@ static char rcsid[] = "$OpenBSD: last.c,v 1.3 1997/01/15 23:42:41 millert Exp $"
 
 #define	NO	0				/* false/no */
 #define	YES	1				/* true/yes */
+#define ATOI2(ar)       ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
 
 static struct utmp	buf[1024];		/* utmp read buffer */
 
@@ -87,12 +88,17 @@ TTY	*ttylist;				/* head of linked list */
 static time_t	currentout;			/* current logout value */
 static long	maxrec;				/* records to display */
 static char	*file = _PATH_WTMP;		/* wtmp file */
+static time_t	snaptime;		        /* if != 0, we will only
+	                                         * report users logged in
+		                                 * at this snapshot time
+						 */
 
 void	 addarg __P((int, char *));
 TTY	*addtty __P((char *));
 void	 hostconv __P((char *));
 void	 onintr __P((int));
 char	*ttyconv __P((char *));
+time_t	 dateconv __P((char *));
 int	 want __P((struct utmp *, int));
 void	 wtmp __P((void));
 
@@ -107,7 +113,8 @@ main(argc, argv)
 	char *p;
 
 	maxrec = -1;
-	while ((ch = getopt(argc, argv, "0123456789f:h:t:")) != -1)
+	snaptime = 0;
+	while ((ch = getopt(argc, argv, "0123456789f:h:t:d:")) != -1)
 		switch (ch) {
 		case '0': case '1': case '2': case '3': case '4':
 		case '5': case '6': case '7': case '8': case '9':
@@ -135,10 +142,15 @@ main(argc, argv)
 		case 't':
 			addarg(TTY_TYPE, ttyconv(optarg));
 			break;
+		case 'd':
+			snaptime = dateconv(optarg);
+			break;
 		case '?':
 		default:
 			(void)fprintf(stderr,
-	"usage: last [-#] [-f file] [-t tty] [-h hostname] [user ...]\n");
+				      "usage: last [-#] [-f file] [-t tty]"
+				      " [-h host] [-d [MMDD]hhmm[.SS]]"
+			              " [user ...]\n");
 			exit(1);
 		}
 
@@ -170,7 +182,7 @@ wtmp()
 	time_t	bl, delta;			/* time difference */
 	int	bytes, wfd;
 	char	*ct, *crmsg;
-
+	int 	snapfound = 0;		        /* found snapshot entry? */
 	if ((wfd = open(file, O_RDONLY, 0)) < 0 || fstat(wfd, &stb) == -1)
 		err(1, "%s", file);
 	bl = (stb.st_size + sizeof(buf) - 1) / sizeof(buf);
@@ -195,7 +207,20 @@ wtmp()
 				currentout = -bp->ut_time;
 				crmsg = strncmp(bp->ut_name, "shutdown",
 				    UT_NAMESIZE) ? "crash" : "shutdown";
-				if (want(bp, NO)) {
+				/* 
+				 * if we're in snapshop mode, we want to
+				 * exit if this shutdown/reboot appears
+				 * while we we are tracking the active
+				 * range
+				 */
+				if (snaptime && snapfound)
+					return;
+				/* 
+				 * don't print shutdown/reboot entries
+				 * unless flagged for and not in snapshot
+				 * mode
+				 */ 
+				if (!snaptime && want(bp, NO)) {
 					ct = ctime(&bp->ut_time);
 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %5.5s \n",
 					    UT_NAMESIZE, UT_NAMESIZE,
@@ -214,7 +239,7 @@ wtmp()
 			 */
 			if ((bp->ut_line[0] == '{' || bp->ut_line[0] == '|')
 			    && !bp->ut_line[1]) {
-				if (want(bp, NO)) {
+				if (want(bp, NO) && !snaptime) {
 					ct = ctime(&bp->ut_time);
 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %5.5s \n",
 				    UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
@@ -236,7 +261,16 @@ wtmp()
 				if (!strncmp(T->tty, bp->ut_line, UT_LINESIZE))
 					break;
 			}
-			if (bp->ut_name[0] && want(bp, YES)) {
+			/* 
+			 * print record if not in snapshot mode and wanted
+			 * or in snapshot mode and in snapshot range
+			 */
+			if (bp->ut_name[0] &&
+			    ((!snaptime && want(bp, YES)) ||
+			     (bp->ut_time < snaptime && 
+			      (T->logout > snaptime || !T->logout ||
+			       T->logout < 0)))) {
+				snapfound = 1;
 				ct = ctime(&bp->ut_time);
 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %5.5s ",
 				UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
@@ -408,6 +442,80 @@ ttyconv(arg)
 	return (arg);
 }
 
+/* 
+ * dateconv --
+ * 	Convert the snapshot time in command line given in the format
+ * 	[[CC]YY]MMDDhhmm[.SS]] to a time_t.
+ * 	Derived from atime_arg1() in usr.bin/touch/touch.c
+ */
+time_t
+dateconv(arg)
+        char *arg;
+{
+        time_t timet;
+        struct tm *t;
+        int yearset;
+        char *p;
+
+        /* Start with the current time. */
+        if (time(&timet) < 0)
+                err(1, "time");
+        if ((t = localtime(&timet)) == NULL)
+                err(1, "localtime");
+
+        /* [[CC]YY]MMDDhhmm[.SS] */
+        if ((p = strchr(arg, '.')) == NULL)
+                t->tm_sec = 0; 		/* Seconds defaults to 0. */
+        else {
+                if (strlen(p + 1) != 2)
+                        goto terr;
+                *p++ = '\0';
+                t->tm_sec = ATOI2(p);
+        }
+
+        yearset = 0;
+        switch (strlen(arg)) {
+        case 12:                	/* CCYYMMDDhhmm */
+                t->tm_year = ATOI2(arg);
+                t->tm_year *= 100;
+                yearset = 1;
+                /* FALLTHOUGH */
+        case 10:                	/* YYMMDDhhmm */
+                if (yearset) {
+                        yearset = ATOI2(arg);
+                        t->tm_year += yearset;
+                } else {
+                        yearset = ATOI2(arg);
+                        if (yearset < 69)
+                                t->tm_year = yearset + 2000;
+                        else
+                                t->tm_year = yearset + 1900;
+                }
+                t->tm_year -= 1900;     /* Convert to UNIX time. */
+                /* FALLTHROUGH */
+        case 8:				/* MMDDhhmm */
+                t->tm_mon = ATOI2(arg);
+                --t->tm_mon;    	/* Convert from 01-12 to 00-11 */
+                t->tm_mday = ATOI2(arg);
+                t->tm_hour = ATOI2(arg);
+                t->tm_min = ATOI2(arg);
+                break;
+        case 4:				/* hhmm */
+                t->tm_hour = ATOI2(arg);
+                t->tm_min = ATOI2(arg);
+                break;
+        default:
+                goto terr;
+        }
+        t->tm_isdst = -1;       	/* Figure out DST. */
+        timet = mktime(t);
+        if (timet == -1)
+terr:           errx(1,
+        "out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");
+        return timet;
+}
+
+
 /*
  * onintr --
  *	on interrupt, we inform the user how far we've gotten