hostnamed: add ACPI and Device Tree chassis detection mechanisms

Heavily "inspired" by systemd.

Signed-off-by: David Heidelberg <david@ixit.cz>

src/hostnamed.c

@@ -81,6 +81,9 @@ hostname_is_valid (const gchar *name)
                                  name, G_REGEX_MULTILINE, 0);
 }
 
+/*
+   Taken with a few minor changes from systemd's hostnamed.c,
+*/
 static gchar *
 guess_chassis ()
 {
@@ -97,9 +100,6 @@ guess_chassis ()
 
 #if defined(__i386__) || defined(__x86_64__)
     /* 
-       Taken with a few minor changes from systemd's hostnamed.c,
-       copyright 2011 Lennart Poettering.
-
        See the SMBIOS Specification 3.5.0 section 7.4.1 for details about the values listed here:
 
        https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.5.0.pdf
@@ -144,6 +144,48 @@ guess_chassis ()
         }
     }
 #endif
+    /* We only list the really obvious cases here as the ACPI data is not really super reliable.
+     *
+     * See the ACPI 5.0 Spec Section 5.2.9.1 for details:
+     *
+     * http://www.acpi.info/DOWNLOADS/ACPIspec50.pdf
+     */
+    if (g_file_get_contents ("/sys/firmware/acpi/pm_profile", &filebuf, NULL, NULL)) {
+        switch (g_ascii_strtoull (filebuf, NULL, 10)) {
+
+        case 1: /* Desktop */
+        case 3: /* Workstation */
+        case 6: /* Appliance PC */
+            ret = g_strdup ("desktop");
+            goto out;
+
+        case 2: /* Mobile */
+            ret = g_strdup ("laptop");
+            goto out;
+
+        case 4: /* Enterprise Server */
+        case 5: /* SOHO Server */
+        case 7: /* Performance Server */
+            ret = g_strdup ("server");
+            goto out;
+
+        case 8: /* Tablet */
+            ret = g_strdup ("tablet");
+            goto out;
+        }
+    }
+
+    /* Query Device Tree for chassis type
+     *
+     * Note that the Devicetree specification uses the very same vocabulary
+     * of chassis types as we do, hence we do not need to translate these types:
+     *
+     * https://github.com/devicetree-org/devicetree-specification/blob/master/source/chapter3-devicenodes.rst */
+    if (g_file_get_contents ("/proc/device-tree/chassis-type", &filebuf, NULL, NULL)) {
+        ret = g_strdup (filebuf);
+        goto out;
+    }
+
   out:
     g_free (filebuf);
     return ret;