From 79308ac147be9e9c889798cba78bab2af05048e1 Mon Sep 17 00:00:00 2001
From: Jiri Kucera <jkucera@redhat.com>
Date: Wed, 17 Jan 2018 13:57:34 +0100
Subject: [PATCH] Fix a segfault in 'man -D --help'

This patch is an adjusted version (due to the patch rejected hunk issues) of its original (by Colin Watson) from: https://git.savannah.gnu.org/cgit/man-db.git/patch/?id=b32977ff73220cd351387abe558fb523d1deedbb

Reported by Jiri Kucera.

* src/man.c (init_html_pager): New function.
(parse_opt): Call init_html_pager rather than setting html_pager to
NULL.
(help_filter): Assert that browser is non-NULL.
(main): Call init_html_pager rather than doing the same thing directly.
* NEWS: Document this.
---
 NEWS      | 10 ++++++++++
 src/man.c | 17 +++++++++++------
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/NEWS b/NEWS
index 366a0263..ff35e884 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,13 @@
+man-db 2.7.7
+============
+
+Major changes since man-db 2.7.6.1:
+
+	Fixes:
+	------
+
+	o Fix a segfault in 'man -D --help'.
+
 man-db 2.7.6.1 (12 December 2016)
 =================================
 
diff --git a/src/man.c b/src/man.c
index 8b11f43e..cb0930b8 100644
--- a/src/man.c
+++ b/src/man.c
@@ -345,6 +345,13 @@ static struct argp_option options[] = {
 	{ 0 }
 };
 
+static void init_html_pager (void)
+{
+	html_pager = getenv ("BROWSER");
+	if (!html_pager)
+		html_pager = WEB_BROWSER;
+}
+
 static error_t parse_opt (int key, char *arg, struct argp_state *state)
 {
 	static int apropos, whatis; /* retain values between calls */
@@ -369,7 +376,7 @@ static error_t parse_opt (int key, char *arg, struct argp_state *state)
 			ditroff = 0;
 			gxditview = NULL;
 			htmlout = 0;
-			html_pager = NULL;
+			init_html_pager ();
 #endif
 			roff_device = want_encoding = extension = pager =
 				locale = alt_system_name = external =
@@ -582,6 +589,7 @@ static char *help_filter (int key, const char *text,
 # ifdef TROFF_IS_GROFF
 		case 'H':
 			browser = html_pager;
+			assert (browser);
 			if (STRNEQ (browser, "exec ", 5))
 				browser += 5;
 			return xasprintf (text, browser);
@@ -4018,11 +4026,8 @@ int main (int argc, char *argv[])
 
 #ifdef TROFF_IS_GROFF
 	/* used in --help, so initialise early */
-	if (!html_pager) {
-		html_pager = getenv ("BROWSER");
-		if (!html_pager)
-			html_pager = WEB_BROWSER;
-	}
+	if (!html_pager)
+		init_html_pager ();
 #endif /* TROFF_IS_GROFF */
 
 	/* First of all, find out if $MANOPT is set. If so, put it in 
-- 
2.14.3