sosreport: Query sos policy for default tmp dir

sos 4.6.2 changed the tmp dir policy [1] from a static /var/tmp to a
dynamic per-distro policy, which happens to be /tmp on Debian/Ubuntu
right now. This is wrong, and there is no official way to query it [2].

To cope, query the sos policy for the tmp-dir, and only fall back to
static /var/tmp if that fails.

[1] sosreport/sos#4062
[2] sosreport/sos#4074

Author: martinpitt

pkg/sosreport/get_report_dir.py

@@ -1,8 +1,17 @@
 import configparser
+import sys
 
 c = configparser.ConfigParser()
 c.read("/etc/sos/sos.conf")
 try:
     print(c["global"]["tmp-dir"])
 except KeyError:
-    print("/var/tmp")
+    # very expensive and internal API, but there is no official way to get the tmp-dir
+    # https://github.com/sosreport/sos/issues/4074
+    try:
+        import sos.policies
+        print(sos.policies.load().get_tmp_dir(None))
+    except Exception as e:
+        # in case the API changes, sane fallback
+        print("Failed to get policy tmp-dir:", e, file=sys.stderr)
+        print("/var/tmp")

pyproject.toml

@@ -41,6 +41,7 @@ module = [
     # these are used from various scripts meant to run on the host
     "dbus",
     "tracer.query",
+    "sos.*",
     "vdo.*",
 ]