Append .html suffix to temporary files enabling browsers to recognise it.

Occasionally one might read a manual page in a webbrowser, e.g.
"MANPAGER=firefox man -T html jq", however temporary files created for
pagers lack file extensions and most web browsers are unable to detect a
file's content without it.

Special case mandoc(1)'s HTML output format by appending the ".html" suffix
to file names such that browsers will actually render HTML as such instead
of showing it as plain text.

Idea and patch from kn@, with minor help from me.

3 files changed, 10 insertions, 8 deletions

diff --git a/main.c b/main.c
index 161cb864..006d5e8a 100644
--- a/main.c
+++ b/main.c
@@ -1,4 +1,4 @@
-/* $Id: main.c,v 1.353 2020/08/07 20:56:55 schwarze Exp $ */
+/* $Id: main.c,v 1.354 2021/03/30 17:16:55 schwarze Exp $ */
 /*
  * Copyright (c) 2010-2012, 2014-2020 Ingo Schwarze <schwarze@openbsd.org>
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -846,6 +846,7 @@ process_onefile(struct mparse *mp, struct manpage *resp, int startdir,
 	if (outst->use_pager) {
 		outst->use_pager = 0;
 		outst->tag_files = term_tag_init(conf->output.outfilename,
+		    outst->outtype == OUTT_HTML ? ".html" : "",
 		    conf->output.tagfilename);
 #if HAVE_PLEDGE
 		if ((conf->output.outfilename != NULL ||
diff --git a/term_tag.c b/term_tag.c
index c448a6ef..c26b9425 100644
--- a/term_tag.c
+++ b/term_tag.c
@@ -1,4 +1,4 @@
-/* $Id: term_tag.c,v 1.5 2020/07/21 15:10:01 schwarze Exp $ */
+/* $Id: term_tag.c,v 1.6 2021/03/30 17:16:55 schwarze Exp $ */
 /*
  * Copyright (c) 2015,2016,2018,2019,2020 Ingo Schwarze <schwarze@openbsd.org>
  *
@@ -47,7 +47,8 @@ static struct tag_files tag_files;
  * but for simplicity, create it anyway.
  */
 struct tag_files *
-term_tag_init(const char *outfilename, const char *tagfilename)
+term_tag_init(const char *outfilename, const char *suffix,
+    const char *tagfilename)
 {
 	struct sigaction	 sa;
 	int			 ofd;	/* In /tmp/, dup(2)ed to stdout. */
@@ -85,9 +86,9 @@ term_tag_init(const char *outfilename, const char *tagfilename)
 	/* Create both temporary output files. */
 
 	if (outfilename == NULL) {
-		(void)strlcpy(tag_files.ofn, "/tmp/man.XXXXXXXXXX",
-		    sizeof(tag_files.ofn));
-		if ((ofd = mkstemp(tag_files.ofn)) == -1) {
+		(void)snprintf(tag_files.ofn, sizeof(tag_files.ofn),
+		    "/tmp/man.XXXXXXXXXX%s", suffix);
+		if ((ofd = mkstemps(tag_files.ofn, strlen(suffix))) == -1) {
 			mandoc_msg(MANDOCERR_MKSTEMP, 0, 0,
 			    "%s: %s", tag_files.ofn, strerror(errno));
 			goto fail;
diff --git a/term_tag.h b/term_tag.h
index f290cf51..f82b1a6e 100644
--- a/term_tag.h
+++ b/term_tag.h
@@ -1,4 +1,4 @@
-/* $Id: term_tag.h,v 1.3 2020/07/21 15:10:01 schwarze Exp $ */
+/* $Id: term_tag.h,v 1.4 2021/03/30 17:16:55 schwarze Exp $ */
 /*
  * Copyright (c) 2015, 2018, 2019, 2020 Ingo Schwarze <schwarze@openbsd.org>
  *
@@ -28,7 +28,7 @@ struct	tag_files {
 };
 
 
-struct tag_files	*term_tag_init(const char *, const char *);
+struct tag_files	*term_tag_init(const char *, const char *, const char *);
 void			 term_tag_write(struct roff_node *, size_t);
 int			 term_tag_close(void);
 void			 term_tag_unlink(void);