Introduce flags NODE_NOSRC and NODE_NOPRT for AST nodes.

Use them to mark generated nodes and nodes that shall not produce output.
Let -Ttree output mode display these new flags.
Use NODE_NOSRC for .Ar, .Mt, and .Pa default arguments.
Use NODE_NOPRT for .Dd, .Dt, and .Os.

These will help to make handling of text production macros more rigorous.

7 files changed, 48 insertions, 18 deletions

diff --git a/mandoc.1 b/mandoc.1
index 10623355..a4dc4233 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -529,6 +529,12 @@ The input column number (starting at one).
 A closing parenthesis if the node is a closing delimiter.
 .It
 A full stop if the node ends a sentence.
+.It
+NOSRC if the node is not in the input file,
+but automatically generated from macros.
+.It
+NOPRT if the node is not supposed to generate output
+for any output format.
 .El
 .El
 .Sh ENVIRONMENT
diff --git a/mdoc_html.c b/mdoc_html.c
index b78a30fa..fffe10f3 100644
--- a/mdoc_html.c
+++ b/mdoc_html.c
@@ -377,6 +377,9 @@ print_mdoc_node(MDOC_ARGS)
 	int		 child;
 	struct tag	*t;
 
+	if (n->flags & NODE_NOPRT)
+		return;
+
 	child = 1;
 	t = h->tags.head;
 	n->flags &= ~MDOC_ENDED;
diff --git a/mdoc_man.c b/mdoc_man.c
index 40baf261..99644281 100644
--- a/mdoc_man.c
+++ b/mdoc_man.c
@@ -1,6 +1,6 @@
 /*	$Id$ */
 /*
- * Copyright (c) 2011-2016 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2011-2017 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -575,6 +575,9 @@ print_node(DECL_ARGS)
 	struct roff_node	*sub;
 	int			 cond, do_sub;
 
+	if (n->flags & NODE_NOPRT)
+		return;
+
 	/*
 	 * Break the line if we were parsed subsequent the current node.
 	 * This makes the page structure be more consistent.
diff --git a/mdoc_term.c b/mdoc_term.c
index 97923a3d..6cdf9d84 100644
--- a/mdoc_term.c
+++ b/mdoc_term.c
@@ -285,6 +285,8 @@ terminal_mdoc(void *arg, const struct roff_man *mdoc)
 			p->defindent = 5;
 		term_begin(p, print_mdoc_head, print_mdoc_foot,
 		    &mdoc->meta);
+		while (n != NULL && n->flags & NODE_NOPRT)
+			n = n->next;
 		if (n != NULL) {
 			if (n->tok != MDOC_Sh)
 				term_vspace(p);
@@ -311,6 +313,9 @@ print_mdoc_node(DECL_ARGS)
 	struct termpair	 npair;
 	size_t		 offset, rmargin;
 
+	if (n->flags & NODE_NOPRT)
+		return;
+
 	chld = 1;
 	offset = p->offset;
 	rmargin = p->rmargin;
@@ -564,6 +569,8 @@ print_bvspace(struct termp *p,
 	/* Do not vspace directly after Ss/Sh. */
 
 	nn = n;
+	while (nn->prev != NULL && nn->prev->flags & NODE_NOPRT)
+		nn = nn->prev;
 	while (nn->prev == NULL) {
 		do {
 			nn = nn->parent;
@@ -1718,11 +1725,15 @@ termp_pf_post(DECL_ARGS)
 static int
 termp_ss_pre(DECL_ARGS)
 {
+	struct roff_node *nn;
 
 	switch (n->type) {
 	case ROFFT_BLOCK:
 		term_newln(p);
-		if (n->prev)
+		for (nn = n->prev; nn != NULL; nn = nn->prev)
+			if ((nn->flags & NODE_NOPRT) == 0)
+				break;
+		if (nn != NULL)
 			term_vspace(p);
 		break;
 	case ROFFT_HEAD:
diff --git a/mdoc_validate.c b/mdoc_validate.c
index bae79cbf..a6225b49 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -945,12 +945,15 @@ post_defaults(POST_ARGS)
 	case MDOC_Ar:
 		mdoc->next = ROFF_NEXT_CHILD;
 		roff_word_alloc(mdoc, nn->line, nn->pos, "file");
+		mdoc->last->flags |= NODE_NOSRC;
 		roff_word_alloc(mdoc, nn->line, nn->pos, "...");
+		mdoc->last->flags |= NODE_NOSRC;
 		break;
 	case MDOC_Pa:
 	case MDOC_Mt:
 		mdoc->next = ROFF_NEXT_CHILD;
 		roff_word_alloc(mdoc, nn->line, nn->pos, "~");
+		mdoc->last->flags |= NODE_NOSRC;
 		break;
 	default:
 		abort();
@@ -1941,6 +1944,8 @@ post_dd(POST_ARGS)
 	char		 *datestr;
 
 	n = mdoc->last;
+	n->flags |= NODE_NOPRT;
+
 	if (mdoc->meta.date != NULL) {
 		mandoc_msg(MANDOCERR_PROLOG_REP, mdoc->parse,
 		    n->line, n->pos, "Dd");
@@ -1958,7 +1963,7 @@ post_dd(POST_ARGS)
 	if (n->child == NULL || n->child->string[0] == '\0') {
 		mdoc->meta.date = mdoc->quick ? mandoc_strdup("") :
 		    mandoc_normdate(mdoc->parse, NULL, n->line, n->pos);
-		goto out;
+		return;
 	}
 
 	datestr = NULL;
@@ -1970,8 +1975,6 @@ post_dd(POST_ARGS)
 		    datestr, n->line, n->pos);
 		free(datestr);
 	}
-out:
-	roff_node_delete(mdoc, n);
 }
 
 static void
@@ -1982,10 +1985,12 @@ post_dt(POST_ARGS)
 	char		 *p;
 
 	n = mdoc->last;
+	n->flags |= NODE_NOPRT;
+
 	if (mdoc->flags & MDOC_PBODY) {
 		mandoc_msg(MANDOCERR_DT_LATE, mdoc->parse,
 		    n->line, n->pos, "Dt");
-		goto out;
+		return;
 	}
 
 	if (mdoc->meta.title != NULL)
@@ -2037,7 +2042,7 @@ post_dt(POST_ARGS)
 		    mdoc->parse, n->line, n->pos,
 		    "Dt %s", mdoc->meta.title);
 		mdoc->meta.vol = mandoc_strdup("LOCAL");
-		goto out;  /* msec and arch remain NULL. */
+		return;  /* msec and arch remain NULL. */
 	}
 
 	mdoc->meta.msec = mandoc_strdup(nn->string);
@@ -2055,7 +2060,7 @@ post_dt(POST_ARGS)
 	/* Optional third argument: architecture. */
 
 	if ((nn = nn->next) == NULL)
-		goto out;
+		return;
 
 	for (p = nn->string; *p != '\0'; p++)
 		*p = tolower((unsigned char)*p);
@@ -2066,9 +2071,6 @@ post_dt(POST_ARGS)
 	if ((nn = nn->next) != NULL)
 		mandoc_vmsg(MANDOCERR_ARG_EXCESS, mdoc->parse,
 		    nn->line, nn->pos, "Dt ... %s", nn->string);
-
-out:
-	roff_node_delete(mdoc, n);
 }
 
 static void
@@ -2096,6 +2098,8 @@ post_os(POST_ARGS)
 	struct roff_node *n;
 
 	n = mdoc->last;
+	n->flags |= NODE_NOPRT;
+
 	if (mdoc->meta.os != NULL)
 		mandoc_msg(MANDOCERR_PROLOG_REP, mdoc->parse,
 		    n->line, n->pos, "Os");
@@ -2116,11 +2120,11 @@ post_os(POST_ARGS)
 	mdoc->meta.os = NULL;
 	deroff(&mdoc->meta.os, n);
 	if (mdoc->meta.os)
-		goto out;
+		return;
 
 	if (mdoc->defos) {
 		mdoc->meta.os = mandoc_strdup(mdoc->defos);
-		goto out;
+		return;
 	}
 
 #ifdef OSNAME
@@ -2137,9 +2141,6 @@ post_os(POST_ARGS)
 	}
 	mdoc->meta.os = mandoc_strdup(defbuf);
 #endif /*!OSNAME*/
-
-out:
-	roff_node_delete(mdoc, n);
 }
 
 /*
diff --git a/roff.h b/roff.h
index 19ec50f4..872d3937 100644
--- a/roff.h
+++ b/roff.h
@@ -1,7 +1,7 @@
-/*	$OpenBSD$	*/
+/*	$Id$	*/
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2013, 2014, 2015 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2013, 2014, 2015, 2017 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -109,6 +109,8 @@ struct	roff_node {
 #define	MAN_VALID	  MDOC_VALID
 #define	MAN_EOS		  MDOC_EOS
 #define	MAN_LINE	  MDOC_LINE
+#define	NODE_NOSRC	 (1 << 8)  /* Generated node, not in input file. */
+#define	NODE_NOPRT	 (1 << 9)  /* Shall not print anything. */
 	int		  prev_font; /* Before entering this node. */
 	int		  aux;     /* Decoded node data, type-dependent. */
 	enum roff_type	  type;    /* AST node type. */
diff --git a/tree.c b/tree.c
index 61a8e19a..3348cb4e 100644
--- a/tree.c
+++ b/tree.c
@@ -168,6 +168,10 @@ print_mdoc(const struct roff_node *n, int indent)
 			putchar(')');
 		if (MDOC_EOS & n->flags)
 			putchar('.');
+		if (NODE_NOSRC & n->flags)
+			printf(" NOSRC");
+		if (NODE_NOPRT & n->flags)
+			printf(" NOPRT");
 		putchar('\n');
 	}