Finally, represent the man(7) .PP and .HP macros by the natural

choice, which is <p> HTML element.  On top of the previous fill-mode
improvements, the key to making this possible is to automatically
close the <p> when required: before headers, subsequent paragraphs,
lists, indented blocks, synopsis blocks, tbl(7) blocks, and before
blocks using no-fill mode.

In man(7) documents, represent the .sp request by a blank line in
no-fill mode and in the same way as .PP in fill mode.

5 files changed, 86 insertions, 77 deletions

diff --git a/usr.bin/mandoc/html.c b/usr.bin/mandoc/html.c
index 197338c66e5..49bc3512bc2 100644
--- a/usr.bin/mandoc/html.c
+++ b/usr.bin/mandoc/html.c
@@ -1,7 +1,7 @@
-/*	$OpenBSD: html.c,v 1.118 2019/01/05 09:14:11 schwarze Exp $ */
+/*	$OpenBSD: html.c,v 1.119 2019/01/06 04:41:15 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2011-2015, 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2011-2015, 2017-2019 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
@@ -76,6 +76,7 @@ static	const struct htmldata htmltags[TAG_MAX] = {
 	{"dl",		HTML_NLALL | HTML_INDENT},
 	{"dt",		HTML_NLAROUND},
 	{"dd",		HTML_NLAROUND | HTML_INDENT},
+	{"p",		HTML_NLAROUND | HTML_INDENT},
 	{"pre",		HTML_NLALL | HTML_NOINDENT},
 	{"var",		0},
 	{"cite",	0},
@@ -263,6 +264,19 @@ print_metaf(struct html *h, enum mandoc_esc deco)
 	}
 }
 
+void
+html_close_paragraph(struct html *h)
+{
+	struct tag	*t;
+
+	for (t = h->tag; t != NULL; t = t->next) {
+		if (t->tag == TAG_P) {
+			print_tagq(h, t);
+			break;
+		}
+	}
+}
+
 /*
  * ROFF_nf switches to no-fill mode, ROFF_fi to fill mode.
  * TOKEN_NONE does not switch.  The old mode is returned.
@@ -285,6 +299,7 @@ html_fillmode(struct html *h, enum roff_tok want)
 			print_tagq(h, t);
 			break;
 		case ROFF_nf:
+			html_close_paragraph(h);
 			print_otag(h, TAG_PRE, "");
 			break;
 		case TOKEN_NONE:
diff --git a/usr.bin/mandoc/html.h b/usr.bin/mandoc/html.h
index 56d085eb23b..27993595b78 100644
--- a/usr.bin/mandoc/html.h
+++ b/usr.bin/mandoc/html.h
@@ -1,7 +1,7 @@
-/*	$OpenBSD: html.h,v 1.60 2019/01/05 09:14:11 schwarze Exp $ */
+/*	$OpenBSD: html.h,v 1.61 2019/01/06 04:41:15 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2017, 2018, 2019 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
@@ -39,6 +39,7 @@ enum	htmltag {
 	TAG_DL,
 	TAG_DT,
 	TAG_DD,
+	TAG_P,
 	TAG_PRE,
 	TAG_VAR,
 	TAG_CITE,
@@ -135,5 +136,6 @@ void		  print_eqn(struct html *, const struct eqn_box *);
 void		  print_paragraph(struct html *);
 void		  print_endline(struct html *);
 
+void		  html_close_paragraph(struct html *);
 enum roff_tok	  html_fillmode(struct html *, enum roff_tok);
 char		 *html_make_id(const struct roff_node *, int);
diff --git a/usr.bin/mandoc/man_html.c b/usr.bin/mandoc/man_html.c
index d2bf1733fdf..b5b11914b0a 100644
--- a/usr.bin/mandoc/man_html.c
+++ b/usr.bin/mandoc/man_html.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: man_html.c,v 1.118 2019/01/05 21:52:57 schwarze Exp $ */
+/*	$OpenBSD: man_html.c,v 1.119 2019/01/06 04:41:15 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2013-2015, 2017-2019 Ingo Schwarze <schwarze@openbsd.org>
@@ -40,14 +40,11 @@ struct	man_html_act {
 	int		(*post)(MAN_ARGS);
 };
 
-static	void		  print_bvspace(struct html *,
-				const struct roff_node *);
 static	void		  print_man_head(const struct roff_meta *,
 				struct html *);
 static	void		  print_man_nodelist(MAN_ARGS);
 static	void		  print_man_node(MAN_ARGS);
 static	int		  man_B_pre(MAN_ARGS);
-static	int		  man_HP_pre(MAN_ARGS);
 static	int		  man_IP_pre(MAN_ARGS);
 static	int		  man_I_pre(MAN_ARGS);
 static	int		  man_OP_pre(MAN_ARGS);
@@ -55,7 +52,6 @@ static	int		  man_PP_pre(MAN_ARGS);
 static	int		  man_RS_pre(MAN_ARGS);
 static	int		  man_SH_pre(MAN_ARGS);
 static	int		  man_SM_pre(MAN_ARGS);
-static	int		  man_SS_pre(MAN_ARGS);
 static	int		  man_SY_pre(MAN_ARGS);
 static	int		  man_UR_pre(MAN_ARGS);
 static	int		  man_abort_pre(MAN_ARGS);
@@ -70,14 +66,14 @@ static	void		  man_root_pre(const struct roff_meta *,
 static	const struct man_html_act man_html_acts[MAN_MAX - MAN_TH] = {
 	{ NULL, NULL }, /* TH */
 	{ man_SH_pre, NULL }, /* SH */
-	{ man_SS_pre, NULL }, /* SS */
+	{ man_SH_pre, NULL }, /* SS */
 	{ man_IP_pre, NULL }, /* TP */
 	{ man_IP_pre, NULL }, /* TQ */
 	{ man_abort_pre, NULL }, /* LP */
 	{ man_PP_pre, NULL }, /* PP */
 	{ man_abort_pre, NULL }, /* P */
 	{ man_IP_pre, NULL }, /* IP */
-	{ man_HP_pre, NULL }, /* HP */
+	{ man_PP_pre, NULL }, /* HP */
 	{ man_SM_pre, NULL }, /* SM */
 	{ man_SM_pre, NULL }, /* SB */
 	{ man_alt_pre, NULL }, /* BI */
@@ -108,27 +104,6 @@ static	const struct man_html_act man_html_acts[MAN_MAX - MAN_TH] = {
 };
 
 
-/*
- * Printing leading vertical space before a block.
- * This is used for the paragraph macros.
- * The rules are pretty simple, since there's very little nesting going
- * on here.  Basically, if we're the first within another block (SS/SH),
- * then don't emit vertical space.  If we are (RS), then do.  If not the
- * first, print it.
- */
-static void
-print_bvspace(struct html *h, const struct roff_node *n)
-{
-	if (n->body != NULL && n->body->child != NULL &&
-	    n->body->child->type == ROFFT_TBL)
-		return;
-
-	if (n->prev == NULL && n->parent->tok != MAN_RS)
-		return;
-
-	print_paragraph(h);
-}
-
 void
 html_man(void *arg, const struct roff_meta *man)
 {
@@ -237,7 +212,8 @@ print_man_node(MAN_ARGS)
 		t = h->tag;
 		if (n->tok < ROFF_MAX) {
 			roff_html_pre(h, n);
-			print_stagq(h, t);
+			if (n->tok != ROFF_sp)
+				print_stagq(h, t);
 			return;
 		}
 
@@ -313,11 +289,23 @@ man_SH_pre(MAN_ARGS)
 {
 	char	*id;
 
-	if (n->type == ROFFT_HEAD) {
+	switch (n->type) {
+	case ROFFT_BLOCK:
+		html_close_paragraph(h);
+		break;
+	case ROFFT_HEAD:
 		id = html_make_id(n, 1);
-		print_otag(h, TAG_H1, "cTi", "Sh", id);
+		if (n->tok == MAN_SH)
+			print_otag(h, TAG_H1, "cTi", "Sh", id);
+		else
+			print_otag(h, TAG_H2, "cTi", "Ss", id);
 		if (id != NULL)
 			print_otag(h, TAG_A, "chR", "permalink", id);
+		break;
+	case ROFFT_BODY:
+		break;
+	default:
+		abort();
 	}
 	return 1;
 }
@@ -378,27 +366,23 @@ man_SM_pre(MAN_ARGS)
 }
 
 static int
-man_SS_pre(MAN_ARGS)
-{
-	char	*id;
-
-	if (n->type == ROFFT_HEAD) {
-		id = html_make_id(n, 1);
-		print_otag(h, TAG_H2, "cTi", "Ss", id);
-		if (id != NULL)
-			print_otag(h, TAG_A, "chR", "permalink", id);
-	}
-	return 1;
-}
-
-static int
 man_PP_pre(MAN_ARGS)
 {
-	if (n->type == ROFFT_HEAD)
+	switch (n->type) {
+	case ROFFT_BLOCK:
+		html_close_paragraph(h);
+		break;
+	case ROFFT_HEAD:
 		return 0;
-	else if (n->type == ROFFT_BLOCK)
-		print_bvspace(h, n);
-
+	case ROFFT_BODY:
+		if (n->child != NULL &&
+		    (n->child->flags & NODE_NOFILL) == 0)
+			print_otag(h, TAG_P, "c",
+			    n->tok == MAN_PP ? "Pp" : "Pp HP");
+		break;
+	default:
+		abort();
+	}
 	return 1;
 }
 
@@ -407,16 +391,21 @@ man_IP_pre(MAN_ARGS)
 {
 	const struct roff_node	*nn;
 
-	if (n->type == ROFFT_BODY) {
-		print_otag(h, TAG_DD, "");
-		return 1;
-	} else if (n->type != ROFFT_HEAD) {
+	switch (n->type) {
+	case ROFFT_BLOCK:
+		html_close_paragraph(h);
 		print_otag(h, TAG_DL, "c", "Bl-tag");
 		return 1;
+	case ROFFT_HEAD:
+		print_otag(h, TAG_DT, "");
+		break;
+	case ROFFT_BODY:
+		print_otag(h, TAG_DD, "");
+		return 1;
+	default:
+		abort();
 	}
 
-	print_otag(h, TAG_DT, "");
-
 	switch(n->tok) {
 	case MAN_IP:  /* Only print the first header element. */
 		if (n->child != NULL)
@@ -439,19 +428,6 @@ man_IP_pre(MAN_ARGS)
 }
 
 static int
-man_HP_pre(MAN_ARGS)
-{
-	if (n->type == ROFFT_HEAD)
-		return 0;
-
-	if (n->type == ROFFT_BLOCK) {
-		print_bvspace(h, n);
-		print_otag(h, TAG_DIV, "c", "HP");
-	}
-	return 1;
-}
-
-static int
 man_OP_pre(MAN_ARGS)
 {
 	struct tag	*tt;
@@ -508,10 +484,18 @@ man_ign_pre(MAN_ARGS)
 static int
 man_RS_pre(MAN_ARGS)
 {
-	if (n->type == ROFFT_HEAD)
+	switch (n->type) {
+	case ROFFT_BLOCK:
+		html_close_paragraph(h);
+		break;
+	case ROFFT_HEAD:
 		return 0;
-	if (n->type == ROFFT_BLOCK)
+	case ROFFT_BODY:
 		print_otag(h, TAG_DIV, "c", "Bd-indent");
+		break;
+	default:
+		abort();
+	}
 	return 1;
 }
 
@@ -520,6 +504,7 @@ man_SY_pre(MAN_ARGS)
 {
 	switch (n->type) {
 	case ROFFT_BLOCK:
+		html_close_paragraph(h);
 		print_otag(h, TAG_TABLE, "c", "Nm");
 		print_otag(h, TAG_TR, "");
 		break;
diff --git a/usr.bin/mandoc/roff_html.c b/usr.bin/mandoc/roff_html.c
index 517a2257ab7..79527ec2e50 100644
--- a/usr.bin/mandoc/roff_html.c
+++ b/usr.bin/mandoc/roff_html.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: roff_html.c,v 1.17 2019/01/05 09:14:11 schwarze Exp $ */
+/*	$OpenBSD: roff_html.c,v 1.18 2019/01/06 04:41:15 schwarze Exp $ */
 /*
  * Copyright (c) 2010 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2014, 2017, 2018, 2019 Ingo Schwarze <schwarze@openbsd.org>
@@ -107,5 +107,11 @@ roff_html_pre_nf(ROFF_HTML_ARGS)
 static void
 roff_html_pre_sp(ROFF_HTML_ARGS)
 {
-	print_paragraph(h);
+	if (html_fillmode(h, TOKEN_NONE) == ROFF_nf) {
+		h->col++;
+		print_endline(h);
+	} else if (n->parent->tok >= MAN_TH)
+		print_otag(h, TAG_P, "c", "Pp");
+	else
+		print_paragraph(h);
 }
diff --git a/usr.bin/mandoc/tbl_html.c b/usr.bin/mandoc/tbl_html.c
index a4a448ef42e..bbde210c570 100644
--- a/usr.bin/mandoc/tbl_html.c
+++ b/usr.bin/mandoc/tbl_html.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tbl_html.c,v 1.26 2018/12/15 23:33:20 schwarze Exp $ */
+/*	$OpenBSD: tbl_html.c,v 1.27 2019/01/06 04:41:15 schwarze Exp $ */
 /*
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2014, 2015, 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
@@ -78,6 +78,7 @@ html_tbl_sulen(const struct roffsu *su, void *arg)
 static void
 html_tblopen(struct html *h, const struct tbl_span *sp)
 {
+	html_close_paragraph(h);
 	if (h->tbl.cols == NULL) {
 		h->tbl.len = html_tbl_len;
 		h->tbl.slen = html_tbl_strlen;