From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 22 Mar 2022 11:58:55 +0000 (+0100)
Subject: sd-device: use path_compare() rather than strcmp() for sorting paths
X-Git-Tag: v251-rc1~75^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F22821%2Fhead;p=thirdparty%2Fsystemd.git

sd-device: use path_compare() rather than strcmp() for sorting paths

When sorting paths it actually matters to use the right comparison
function. Example:

```
a/x
a-b/y
a_/z
```

I think people would probably expect this:

```
a/x
a-b/y
a_a/z
```

but if you use strcmp() instead of path_compare() you'd instead get:

```
a-b/y
a/x
a_a/z
```

That's because `/` is between `-` and `a` in the ascii table. I think
that's quite confusing, and we shouldn#t order that way hence.

As discussed: https://github.com/systemd/systemd/pull/22662#discussion_r831174776
---

diff --git a/src/libsystemd/sd-device/device-enumerator.c b/src/libsystemd/sd-device/device-enumerator.c
index 1379764156e..14794fb3af5 100644
--- a/src/libsystemd/sd-device/device-enumerator.c
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -323,7 +323,7 @@ static int device_compare(sd_device * const *a, sd_device * const *b) {
         if (r != 0)
                 return r;
 
-        return strcmp(devpath_a, devpath_b);
+        return path_compare(devpath_a, devpath_b);
 }
 
 static int enumerator_sort_devices(sd_device_enumerator *enumerator) {