add --noremove option to daemon for disabling the automatic removal o…

…f interfaces from database that aren't currently visible and haven't seen any traffic

CHANGES

@@ -25,6 +25,9 @@
      regardless of the number of interfaces in the database
    - Add --startempty option to daemon for starting and keeping the daemon
      running even if no interfaces were discovered and the database is empty
+   - Add --noremove option to daemon for disabling the automatic removal of
+     interfaces from database that aren't currently visible and haven't seen
+     any traffic
 
 
 2.11 / 19-Aug-2023

man/vnstatd.8

@@ -21,6 +21,7 @@ vnstatd \- daemon based database updating for vnStat
 .RB [ \-\-initdb ]
 .RB [ \-\-noadd ]
 .RB [ \-\-nodaemon ]
+.RB [ \-\-noremove ]
 .RB [ \-\-pidfile
 .IR file ]
 .RB [ \-\-startempty ]
@@ -150,6 +151,11 @@ added regardless of this option.
 Stay in foreground attached to the current terminal and start the update
 process.
 
+.TP
+.B "--noremove"
+Disable automatic removal of interfaces from database that aren't currently visible
+and haven't seen any traffic.
+
 .TP
 .BI "-p, --pidfile " file
 Write the process id to

src/daemon.c

@@ -277,6 +277,7 @@ void initdstate(DSTATE *s)
 	s->sync = 0;
 	s->forcesave = 0;
 	s->noadd = 0;
+	s->noremove = 0;
 	s->initdb = 0;
 	s->startempty = 0;
 	s->iflisthash = 0;
@@ -674,7 +675,7 @@ void flushcachetodisk(DSTATE *s)
 			}
 		}
 
-		if (!iterator->active && !logcount) {
+		if (!s->noremove && !iterator->active && !logcount) {
 			/* throw away if interface hasn't seen any data and is disabled */
 			if (!iterator->currx && !iterator->curtx) {
 				ret = db_getinterfaceinfo(iterator->interface, &info);

src/daemon.h

@@ -4,7 +4,7 @@
 typedef struct {
 	int updateinterval, saveinterval;
 	short running, dodbsave, rundaemon;
-	short dbsaved, showhelp, sync, forcesave, noadd, initdb, startempty;
+	short dbsaved, showhelp, sync, forcesave, noadd, noremove, initdb, startempty;
 	short bootdetected, cleanuphour, dbretrycount;
 	uint32_t iflisthash;
 	uint64_t dbifcount;

src/vnstatd.c

@@ -267,6 +267,7 @@ void showhelp(void)
 	printf("      --alwaysadd [mode]       automatically start monitoring all new interfaces\n");
 	printf("      --noadd                  disable discovery of interfaces when database\n");
 	printf("                               contains none\n");
+	printf("      --noremove               disable removal of never seen interfaces\n");
 	printf("      --startempty             start even when database is empty\n\n");
 
 	printf("See also \"man vnstatd\".\n");
@@ -318,6 +319,8 @@ void parseargs(DSTATE *s, int argc, char **argv)
 			}
 		} else if (strcmp(argv[currentarg], "--noadd") == 0) {
 			s->noadd = 1;
+		} else if (strcmp(argv[currentarg], "--noremove") == 0) {
+			s->noremove = 1;
 		} else if (strcmp(argv[currentarg], "--alwaysadd") == 0) {
 			if (currentarg + 1 < argc && (strlen(argv[currentarg + 1]) == 1 || ishelprequest(argv[currentarg + 1]))) {
 				if (!isdigit(argv[currentarg + 1][0]) || atoi(argv[currentarg + 1]) > 1 || atoi(argv[currentarg + 1]) < 0) {