fix expiration completion during --noop run

make sure that an expiration calculation run is performed if ongoing
expiration transactions have been loaded from the journal. this has the
nice side effect of centralizing the regular trigger condition as well.

flags_set_p2() is also adjusted to query S_NEXPIRE only if an expiration
is actually ongoing, like the flag propagation submission loop already
did.

this went unnoticed, because expiration upon arrival of new messages
wasn't autotested at all - despite being the common case.

src/run-tests.pl

@@ -1210,6 +1210,31 @@ my @X32 = (
 );
 test("max messages vs. unread", \@x30, \@X32, \@O32);
 
+my @x33 = (
+  G, D, G,
+  A, "*F", "*F", "*F",
+  B, "*", "*", "*S",
+  C, "*S", "*", "*",
+  D, "*S", "", "",
+  E, "*", "*", "*S",
+  F, "*S", "*S", "*S",
+  G, "*", "*", "*S",
+  H, "*", "", "",
+  I, "*", "", "",
+);
+
+my @X33 = (
+  I, F, I,
+  B, "+S", "+~S", "+T",
+  C, "", "+~S", "+ST",
+  E, "+S", "+~S", "+T",
+  F, "", "+~", "+T",
+  G, "+S", "+S", "",
+  H, "", "*", "*",
+  I, "", "*", "*",
+);
+test("max messages + expire - full", \@x33, \@X33, \@O31);
+
 my @x38 = (
   F, C, 0,
   A, "*FS", "*FS", "*S",

src/sync.c

@@ -714,6 +714,8 @@ box_opened2( sync_vars_t *svars, int t )
 				any_dummies[!srec->uid[F] ? F : N]++;
 			if (!svars->replayed)
 				continue;
+			if ((shifted_bit(srec->status, S_EXPIRE, S_EXPIRED) ^ srec->status) & S_EXPIRED)
+				svars->any_expiring = 1;
 			if (srec->status & S_PURGE) {
 				any_purges[srec->uid[F] ? F : N]++;
 			} else if (srec->status & S_PENDING) {
@@ -787,7 +789,10 @@ box_opened2( sync_vars_t *svars, int t )
 	// but it's more natural to treat it as read-only in that case.
 	// OP_RENEW makes sense only for legacy S_SKIPPED entries.
 	if ((chan->ops[N] & (OP_NEW|OP_RENEW|OP_FLAGS)) && chan->max_messages)
+		svars->any_expiring = 1;
+	if (svars->any_expiring) {
 		opts[N] |= OPEN_OLD | OPEN_FLAGS;
+	}
 	svars->opts[F] = svars->drv[F]->prepare_load_box( ctx[F], opts[F] );
 	svars->opts[N] = svars->drv[N]->prepare_load_box( ctx[N], opts[N] );
 
@@ -1228,7 +1233,7 @@ box_loaded( int sts, message_t *msgs, int total_msgs, int recent_msgs, void *aux
 		}
 	}
 
-	if ((svars->chan->ops[N] & (OP_NEW|OP_RENEW|OP_FLAGS)) && svars->chan->max_messages) {
+	if (svars->any_expiring) {
 		// Note: When this branch is entered, we have loaded all near side messages.
 		/* Expire excess messages. Important (flagged, unread, or unpropagated) messages
 		 * older than the first not expired message are not counted towards the total. */
@@ -1585,20 +1590,24 @@ flags_set_p2( sync_vars_t *svars, sync_rec_t *srec, int t )
 			srec->flags = nflags;
 		}
 		if (t == N) {
+			uchar ex = (srec->status / S_EXPIRE) & 1;
+			uchar exd = (srec->status / S_EXPIRED) & 1;
+			if (ex != exd) {
 				uchar nex = (srec->status / S_NEXPIRE) & 1;
-			if (nex != ((srec->status / S_EXPIRED) & 1)) {
+				if (nex == ex) {
 					if (nex && svars->maxxfuid < srec->uid[F])
 						svars->maxxfuid = srec->uid[F];
 					srec->status = (srec->status & ~S_EXPIRED) | (nex * S_EXPIRED);
 					JLOG( "~ %u %u %d", (srec->uid[F], srec->uid[N], srec->status & S_LOGGED),
 					      "expired %d - commit", nex );
-			} else if (nex != ((srec->status / S_EXPIRE) & 1)) {
+				} else {
 					srec->status = (srec->status & ~S_EXPIRE) | (nex * S_EXPIRE);
 					JLOG( "~ %u %u %d", (srec->uid[F], srec->uid[N], srec->status & S_LOGGED),
 					      "expire %d - cancel", nex );
 				}
 			}
 		}
+	}
 }
 
 typedef struct {

src/sync_p.h

@@ -53,7 +53,7 @@ typedef struct {
 	const char *orig_name[2];
 	message_t *msgs[2], *new_msgs[2];
 	uint_array_alloc_t trashed_msgs[2];
-	int state[2], lfd, ret, existing, replayed;
+	int state[2], lfd, ret, existing, replayed, any_expiring;
 	uint ref_count, nsrecs, opts[2];
 	uint new_pending[2], flags_pending[2], trash_pending[2];
 	uint maxuid[2];     // highest UID that was already propagated