In the mdoc(7) parser, inspect roff registers early such that all parts

of the parser can use the resulting cues.  In particular, this allows
to use .nr nS to force SYNOPSIS-style .Nm indentation outside the
SYNOPSIS as needed by ifconfig(8).

To actually make this useable, .Pp must rewind .Nm, or the rest of the
section would end up indented.  Implement a quick hack for now,
a generic solution can be designed later.

ok kristaps@ and tested by sobrado@

1 files changed, 18 insertions, 14 deletions

diff --git a/mdoc.c b/mdoc.c
index 5fc9ed95..000205be 100644
--- a/mdoc.c
+++ b/mdoc.c
@@ -239,6 +239,20 @@ mdoc_parseln(struct mdoc *m, int ln, char *buf, int offs)
 		return(0);
 
 	m->flags |= MDOC_NEWLINE;
+
+	/*
+	 * Let the roff nS register switch SYNOPSIS mode early,
+	 * such that the parser knows at all times
+	 * whether this mode is on or off.
+	 * Note that this mode is also switched by the Sh macro.
+	 */
+	if (m->regs->regs[(int)REG_nS].set) {
+		if (m->regs->regs[(int)REG_nS].v.u)
+			m->flags |= MDOC_SYNOPSIS;
+		else
+			m->flags &= ~MDOC_SYNOPSIS;
+	}
+
 	return(('.' == buf[offs] || '\'' == buf[offs]) ? 
 			mdoc_pmacro(m, ln, buf, offs) :
 			mdoc_ptext(m, ln, buf, offs));
@@ -373,24 +387,14 @@ node_alloc(struct mdoc *m, int line, int pos,
 
 	/* Flag analysis. */
 
+	if (MDOC_SYNOPSIS & m->flags)
+		p->flags |= MDOC_SYNPRETTY;
+	else
+		p->flags &= ~MDOC_SYNPRETTY;
 	if (MDOC_NEWLINE & m->flags)
 		p->flags |= MDOC_LINE;
 	m->flags &= ~MDOC_NEWLINE;
 
-	/* Section analysis. */
-
-	if (SEC_SYNOPSIS == p->sec)
-		p->flags |= MDOC_SYNPRETTY;
-
-	/* Register analysis. */
-
-	if (m->regs->regs[(int)REG_nS].set) {
-		if (m->regs->regs[(int)REG_nS].v.u)
-			p->flags |= MDOC_SYNPRETTY;
-		else
-			p->flags &= ~MDOC_SYNPRETTY;
-	}
-
 	return(p);
 }