===================================================================
RCS file: /cvs/mandoc/mandocdb.c,v
retrieving revision 1.246
retrieving revision 1.252
diff -u -p -r1.246 -r1.252
--- mandoc/mandocdb.c	2017/04/24 23:06:18	1.246
+++ mandoc/mandocdb.c	2017/07/15 13:17:49	1.252
@@ -1,4 +1,4 @@
-/*	$Id: mandocdb.c,v 1.246 2017/04/24 23:06:18 schwarze Exp $ */
+/*	$Id: mandocdb.c,v 1.252 2017/07/15 13:17:49 schwarze Exp $ */
 /*
  * Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011-2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -302,11 +302,8 @@ static	const struct mdoc_handler __mdocs[MDOC_MAX - MD
 	{ NULL, 0, 0 },  /* En */
 	{ NULL, TYPE_Dx, NODE_NOSRC },  /* Dx */
 	{ NULL, 0, 0 },  /* %Q */
-	{ NULL, 0, 0 },  /* br */
-	{ NULL, 0, 0 },  /* sp */
 	{ NULL, 0, 0 },  /* %U */
 	{ NULL, 0, 0 },  /* Ta */
-	{ NULL, 0, 0 },  /* ll */
 };
 static	const struct mdoc_handler *const mdocs = __mdocs - MDOC_Dd;
 
@@ -423,7 +420,8 @@ mandocdb(int argc, char *argv[])
 
 	exitcode = (int)MANDOCLEVEL_OK;
 	mchars_alloc();
-	mp = mparse_alloc(mparse_options, MANDOCLEVEL_BADARG, NULL, NULL);
+	mp = mparse_alloc(mparse_options, MANDOCLEVEL_BADARG, NULL,
+	    MANDOC_OS_OTHER, NULL);
 	mandoc_ohash_init(&mpages, 6, offsetof(struct mpage, inodev));
 	mandoc_ohash_init(&mlinks, 6, offsetof(struct mlink, file));
 
@@ -1547,8 +1545,11 @@ parse_mdoc(struct mpage *mpage, const struct roff_meta
 {
 
 	for (n = n->child; n != NULL; n = n->next) {
-		if (n->tok == TOKEN_NONE || n->flags & mdocs[n->tok].taboo)
+		if (n->tok == TOKEN_NONE ||
+		    n->tok < ROFF_MAX ||
+		    n->flags & mdocs[n->tok].taboo)
 			continue;
+		assert(n->tok >= MDOC_Dd && n->tok < MDOC_MAX);
 		switch (n->type) {
 		case ROFFT_ELEM:
 		case ROFFT_BLOCK:
@@ -2122,6 +2123,23 @@ dbwrite(struct dba *dba)
 	int		 status;
 	pid_t		 child;
 
+	/*
+	 * Do not write empty databases, and delete existing ones
+	 * when makewhatis -u causes them to become empty.
+	 */
+
+	dba_array_start(dba->pages);
+	if (dba_array_next(dba->pages) == NULL) {
+		if (unlink(MANDOC_DB) == -1 && errno != ENOENT)
+			say(MANDOC_DB, "&unlink");
+		return;
+	}
+
+	/*
+	 * Build the database in a temporary file,
+	 * then atomically move it into place.
+	 */
+
 	if (dba_write(MANDOC_DB "~", dba) != -1) {
 		if (rename(MANDOC_DB "~", MANDOC_DB) == -1) {
 			exitcode = (int)MANDOCLEVEL_SYSERR;
@@ -2130,6 +2148,11 @@ dbwrite(struct dba *dba)
 		}
 		return;
 	}
+
+	/*
+	 * We lack write permission and cannot replace the database
+	 * file, but let's at least check whether the data changed.
+	 */
 
 	(void)strlcpy(tfn, "/tmp/mandocdb.XXXXXXXX", sizeof(tfn));
 	if (mkdtemp(tfn) == NULL) {