From: Bartosz Golaszewski <brgl@bgdev.pl>
Date: Thu, 8 Apr 2021 12:30:46 +0000 (+0200)
Subject: gpioset: fix a segfault with default mode
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=eb63fb88512fdb567262b78e930e8dd3441efa34;p=qemu-gpiodev%2Flibgpiod.git

gpioset: fix a segfault with default mode

The default mode (exit) doesn't have a callback so we need to check if
the callback funtion pointer isn't NULL.

Fixes: 9b6e6d268671 ("ctxless: drop all context-less interfaces")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
---

diff --git a/tools/gpio-tools-test.bats b/tools/gpio-tools-test.bats
index b35a36e..a5b97e1 100755
--- a/tools/gpio-tools-test.bats
+++ b/tools/gpio-tools-test.bats
@@ -599,6 +599,14 @@ teardown() {
 	output_regex_match ".*can't specify wait time in this mode"
 }
 
+@test "gpioset: default mode" {
+	gpio_mockup_probe 8 8 8
+
+	run_tool gpioset "$(gpio_mockup_chip_name 1)" 0=1
+
+	test "$status" -eq "0"
+}
+
 @test "gpioset: invalid mapping" {
 	gpio_mockup_probe 8 8 8
 
diff --git a/tools/gpioset.c b/tools/gpioset.c
index a088ec6..7882b53 100644
--- a/tools/gpioset.c
+++ b/tools/gpioset.c
@@ -302,7 +302,8 @@ int main(int argc, char **argv)
 	if (rv)
 		die_perror("unable to request lines");
 
-	mode->callback(&cbdata);
+	if (mode->callback)
+		mode->callback(&cbdata);
 
 	gpiod_line_release_bulk(lines);
 	gpiod_chip_unref(chip);