mail, node: Improve handling of various edge cases.

* modules: Don't attempt STARTTLS if io_tls isn't loaded, since it will fail.
* net_imap: Emit debug instead of warning log if cached UIDVALIDITY is empty.
* pty.c, socket.c: Adjust debug and warning log levels.

bbs/pty.c

@@ -728,7 +728,7 @@ void *pty_master(void *varg)
 					 * if it's running in raw mode and not exiting gracefully, but terminals don't
 					 * account for that sort of thing and neither should we.
 					 */
-					bbs_debug(3, "Received ^%c, forwarding it to child process\n", sigchar);
+					bbs_debug(10, "Received ^%c, forwarding it to child process\n", sigchar);
 				} else {
 					/* Now, if we're not executing a child process, things are very different.
 					 * In this case, it actually makes sense to do some processing of these signals ourselves, too,

bbs/socket.c

@@ -1565,10 +1565,10 @@ int bbs_multi_poll(struct pollfd pfds[], int numfds, int ms)
 	return __bbs_multi_poll(NULL, pfds, numfds, ms);
 }
 
-/* This is not an assertion, since it can legitimately happen sometimes and that would be overkill. */
+/* This is not an assertion, or even a warning, since it can legitimately happen right after a node disconnects and that would be overkill. */
 #define REQUIRE_SLAVE_FD(node) \
 	if (node->slavefd == -1) { \
-		bbs_warning("Node %d has no active slave fd\n", node->id); \
+		bbs_debug(1, "Node %d has no active slave fd\n", node->id); \
 		return -1; \
 	}
 

modules/mod_smtp_client.c

@@ -162,6 +162,10 @@ int bbs_smtp_client_starttls(struct bbs_smtp_client *restrict smtpclient)
 		bbs_error("Can't do STARTTLS, connection is already secure\n");
 		return -1;
 	}
+	if (!ssl_available()) {
+		bbs_error("Can't do STARTTLS, TLS module is not loaded\n");
+		return -1;
+	}
 	if (smtpclient->caps & SMTP_CAPABILITY_STARTTLS) {
 		bbs_smtp_client_send(smtpclient, "STARTTLS\r\n");
 		SMTP_CLIENT_EXPECT_FINAL(smtpclient, 2500, "220");

modules/mod_smtp_delivery_external.c

@@ -450,7 +450,12 @@ static int __attribute__ ((nonnull (2, 3, 9, 17))) try_send(struct smtp_session
 	if (!use_implicit_tls) {
 		if (allow_starttls) {
 			if (smtpclient.caps & SMTP_CAPABILITY_STARTTLS) {
-				if (bbs_smtp_client_starttls(&smtpclient)) {
+				if (!ssl_available() && require_starttls_out) {
+					bbs_warning("Encryption is mandatory, but TLS module is not loaded. Delivery failed.\n");
+					snprintf(buf, len, "TLS subsystem is unavailable");
+					res = -2;
+					goto cleanup;
+				} else if (bbs_smtp_client_starttls(&smtpclient)) {
 					res = -2;
 					goto cleanup; /* Abort if we were told STARTTLS was available but failed to negotiate. */
 				}

modules/mod_smtp_fetchmail.c

@@ -122,7 +122,7 @@ static int fetch_single_host(const char *hostname, struct stringlist *domains)
 		bbs_warning("SMTP server %s does not support ETRN, unable to fetch mail\n", hostname);
 		goto cleanup;
 	}
-	if (smtpclient.caps & SMTP_CAPABILITY_STARTTLS) {
+	if (smtpclient.caps & SMTP_CAPABILITY_STARTTLS && ssl_available()) {
 		if (bbs_smtp_client_starttls(&smtpclient)) {
 			goto cleanup; /* Abort if we were told STARTTLS was available but failed to negotiate. */
 		}

nets/net_imap.c

@@ -3012,7 +3012,9 @@ static int handle_remote_move(struct imap_session *imap, char *dest, const char
 						goto cleanup;
 					}
 					/* Could get an untagged EXISTS at this point */
-					IMAP_CLIENT_EXPECT_EVENTUALLY(&destclient->client, 5, tagged_resp); /* tagged OK */
+					if (imap_client_wait_response(destclient, -1, SEC_MS(5))) { /* tagged OK */
+						goto cleanup;
+					}
 				}
 			} else {
 				if (destfd != -1) {

nets/net_imap/imap_client_status.c

@@ -203,7 +203,9 @@ static int status_size_fetch_incremental(struct imap_client *client, const char
 	/* Compare MESSAGES and UIDNEXT from the old and new responses */
 	if (parse_status_item(old, "UIDVALIDITY", &oldv) || parse_status_item(new, "UIDVALIDITY", &newv)) {
 		if (strlen_zero(old)) {
-			bbs_warning("Empty UIDVALIDITY in comparison, cannot rely on cache (%s / %s)\n", old, new);
+			/* This will happen the first time a particular remote IMAP folder is accessed...
+			 * we obviously won't have any UIDVALIDITY cached for it. */
+			bbs_debug(5, "Empty UIDVALIDITY in comparison, cannot rely on cache (%s / %s)\n", old, new);
 		} else {
 			bbs_warning("UIDVALIDITY parsing error, cannot rely on cache (%s / %s)\n", old, new);
 		}