From c9d5c9c0e19eea79ca0f09fe58e5c0b76b8001e2 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 28 Nov 2016 19:41:20 +0100
Subject: [PATCH] core: make unit_free() accept NULL pointers

We generally try to make our destructors robust regarding NULL pointers, much
in the same way as glibc's free(). Do this also for unit_free().

Follow-up for #4748.
---
 src/core/device.c | 2 +-
 src/core/mount.c  | 2 +-
 src/core/swap.c   | 2 +-
 src/core/unit.c   | 3 ++-
 4 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/core/device.c b/src/core/device.c
index 8e2e3c7bedc..074e93ffe2e 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -359,7 +359,7 @@ static int device_setup_unit(Manager *m, struct udev_device *dev, const char *pa
 fail:
         log_unit_warning_errno(u, r, "Failed to set up device unit: %m");
 
-        if (delete && u)
+        if (delete)
                 unit_free(u);
 
         return r;
diff --git a/src/core/mount.c b/src/core/mount.c
index 1c2be28d55d..0c4d061c276 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -1509,7 +1509,7 @@ static int mount_setup_unit(
 fail:
         log_warning_errno(r, "Failed to set up mount unit: %m");
 
-        if (delete && u)
+        if (delete)
                 unit_free(u);
 
         return r;
diff --git a/src/core/swap.c b/src/core/swap.c
index bf404db8c30..e9468e105ca 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -420,7 +420,7 @@ static int swap_setup_unit(
 fail:
         log_unit_warning_errno(u, r, "Failed to load swap unit: %m");
 
-        if (delete && u)
+        if (delete)
                 unit_free(u);
 
         return r;
diff --git a/src/core/unit.c b/src/core/unit.c
index cba6342ecaa..e485c01fc10 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -516,7 +516,8 @@ void unit_free(Unit *u) {
         Iterator i;
         char *t;
 
-        assert(u);
+        if (!u)
+                return;
 
         if (u->transient_file)
                 fclose(u->transient_file);