warn about parentheses in function names after .Fn and .Fo;

particularly useful when converting from other languages to mdoc(7);
feature suggested by bentley@

7 files changed, 64 insertions, 7 deletions

diff --git a/regress/usr.bin/mandoc/mdoc/Fo/Makefile b/regress/usr.bin/mandoc/mdoc/Fo/Makefile
index 892440232e7..6a2ac068a77 100644
--- a/regress/usr.bin/mandoc/mdoc/Fo/Makefile
+++ b/regress/usr.bin/mandoc/mdoc/Fo/Makefile
@@ -1,7 +1,7 @@
-# $OpenBSD: Makefile,v 1.9 2014/07/02 20:18:42 schwarze Exp $
+# $OpenBSD: Makefile,v 1.10 2014/10/11 21:14:11 schwarze Exp $
 
-REGRESS_TARGETS = basic section break noarg font eos obsolete
-LINT_TARGETS	= noarg obsolete
+REGRESS_TARGETS = basic break eos font noarg obsolete section warn
+LINT_TARGETS	= noarg obsolete warn
 
 # groff does not handle .nr nS
 
diff --git a/regress/usr.bin/mandoc/mdoc/Fo/warn.in b/regress/usr.bin/mandoc/mdoc/Fo/warn.in
new file mode 100644
index 00000000000..d41e658ce3b
--- /dev/null
+++ b/regress/usr.bin/mandoc/mdoc/Fo/warn.in
@@ -0,0 +1,13 @@
+.Dd October 11, 2014
+.Dt FO-WARN 1
+.Os OpenBSD
+.Sh NAME
+.Nm Fo-warn
+.Nd warnings related to function blocks
+.Sh SYNOPSIS
+.Ft double
+.Fo sin()
+.Fa "double x"
+.Fc
+.Ft double
+.Fn atan2 "double y, double x"
diff --git a/regress/usr.bin/mandoc/mdoc/Fo/warn.out_ascii b/regress/usr.bin/mandoc/mdoc/Fo/warn.out_ascii
new file mode 100644
index 00000000000..fd1890b560c
--- /dev/null
+++ b/regress/usr.bin/mandoc/mdoc/Fo/warn.out_ascii
@@ -0,0 +1,13 @@
+FO-WARN(1)                  General Commands Manual                 FO-WARN(1)
+
+NNAAMMEE
+     FFoo--wwaarrnn - warnings related to function blocks
+
+SSYYNNOOPPSSIISS
+     _d_o_u_b_l_e
+     ssiinn(())(_d_o_u_b_l_e _x);
+
+     _d_o_u_b_l_e
+     aattaann22(_d_o_u_b_l_e _y_, _d_o_u_b_l_e _x);
+
+OpenBSD                        October 11, 2014                        OpenBSD
diff --git a/regress/usr.bin/mandoc/mdoc/Fo/warn.out_lint b/regress/usr.bin/mandoc/mdoc/Fo/warn.out_lint
new file mode 100644
index 00000000000..09fc534fda3
--- /dev/null
+++ b/regress/usr.bin/mandoc/mdoc/Fo/warn.out_lint
@@ -0,0 +1,2 @@
+mandoc: warn.in:9:8: WARNING: parenthesis in function name: sin()
+mandoc: warn.in:13:19: WARNING: comma in function argument: double y, double x
diff --git a/usr.bin/mandoc/mandoc.h b/usr.bin/mandoc/mandoc.h
index 161020e9b86..b2a531adfea 100644
--- a/usr.bin/mandoc/mandoc.h
+++ b/usr.bin/mandoc/mandoc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mandoc.h,v 1.103 2014/10/10 15:25:06 schwarze Exp $ */
+/*	$OpenBSD: mandoc.h,v 1.104 2014/10/11 21:14:11 schwarze Exp $ */
 /*
  * Copyright (c) 2010, 2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -114,6 +114,7 @@ enum	mandocerr {
 	MANDOCERR_BL_SKIPW, /* skipping -width argument: Bl -type */
 	MANDOCERR_AT_BAD, /* unknown AT&T UNIX version: At version */
 	MANDOCERR_FA_COMMA, /* comma in function argument: arg */
+	MANDOCERR_FN_PAREN, /* parenthesis in function name: arg */
 	MANDOCERR_RS_BAD, /* invalid content in Rs block: macro */
 	MANDOCERR_SM_BAD, /* invalid Boolean argument: macro arg */
 	MANDOCERR_FT_BAD, /* unknown font, skipping request: ft font */
diff --git a/usr.bin/mandoc/mdoc_validate.c b/usr.bin/mandoc/mdoc_validate.c
index 2cc58af547e..acc44b3f45a 100644
--- a/usr.bin/mandoc/mdoc_validate.c
+++ b/usr.bin/mandoc/mdoc_validate.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdoc_validate.c,v 1.166 2014/09/12 00:53:21 schwarze Exp $ */
+/*	$OpenBSD: mdoc_validate.c,v 1.167 2014/10/11 21:14:11 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -100,6 +100,8 @@ static	int	 post_es(POST_ARGS);
 static	int	 post_eoln(POST_ARGS);
 static	int	 post_ex(POST_ARGS);
 static	int	 post_fa(POST_ARGS);
+static	int	 post_fn(POST_ARGS);
+static	int	 post_fname(POST_ARGS);
 static	int	 post_fo(POST_ARGS);
 static	int	 post_hyph(POST_ARGS);
 static	int	 post_hyphtext(POST_ARGS);
@@ -160,7 +162,7 @@ static	const struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, post_fa },			/* Fa */
 	{ NULL, ewarn_ge1 },			/* Fd */
 	{ NULL, NULL },				/* Fl */
-	{ NULL, post_fa },			/* Fn */
+	{ NULL, post_fn },			/* Fn */
 	{ NULL, NULL },				/* Ft */
 	{ NULL, NULL },				/* Ic */
 	{ NULL, ewarn_eq1 },			/* In */
@@ -999,11 +1001,36 @@ post_eoln(POST_ARGS)
 }
 
 static int
+post_fname(POST_ARGS)
+{
+	const struct mdoc_node *n;
+	size_t pos;
+
+	n = mdoc->last->child;
+	pos = strcspn(n->string, "()");
+	if (n->string[pos] != '\0')
+		mandoc_msg(MANDOCERR_FN_PAREN, mdoc->parse,
+		    n->line, n->pos + pos, n->string);
+	return(1);
+}
+
+static int
+post_fn(POST_ARGS)
+{
+
+	post_fname(mdoc);
+	post_fa(mdoc);
+	return(1);
+}
+
+static int
 post_fo(POST_ARGS)
 {
 
 	hwarn_eq1(mdoc);
 	bwarn_ge1(mdoc);
+	if (mdoc->last->type == MDOC_HEAD)
+		post_fname(mdoc);
 	return(1);
 }
 
diff --git a/usr.bin/mandoc/read.c b/usr.bin/mandoc/read.c
index 11e2b2a6ffc..70eaf3a2751 100644
--- a/usr.bin/mandoc/read.c
+++ b/usr.bin/mandoc/read.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: read.c,v 1.64 2014/09/12 00:53:21 schwarze Exp $ */
+/*	$OpenBSD: read.c,v 1.65 2014/10/11 21:14:11 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -153,6 +153,7 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	"skipping -width argument",
 	"unknown AT&T UNIX version",
 	"comma in function argument",
+	"parenthesis in function name",
 	"invalid content in Rs block",
 	"invalid Boolean argument",
 	"unknown font, skipping request",