bluez/transient-hostname-fix.patch

From e515f4b6e25c971c47ab79e9cbdfa17119bbde23 Mon Sep 17 00:00:00 2001
From: Bastien Nocera <hadess@hadess.net>
Date: Wed, 9 Nov 2022 16:17:55 +0100
Subject: [PATCH 1/2] hostname: Add '' around printed strings

Otherwise we can't see whether the string is nul, or empty.
---
 plugins/hostname.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/plugins/hostname.c b/plugins/hostname.c
index 1a9513adb..14b6450b5 100644
--- a/plugins/hostname.c
+++ b/plugins/hostname.c
@@ -128,7 +128,7 @@ static void property_changed(GDBusProxy *proxy, const char *name,
 
 			dbus_message_iter_get_basic(iter, &str);
 
-			DBG("pretty hostname: %s", str);
+			DBG("pretty hostname: '%s'", str);
 
 			g_free(pretty_hostname);
 			pretty_hostname = g_strdup(str);
@@ -146,7 +146,7 @@ static void property_changed(GDBusProxy *proxy, const char *name,
 
 			dbus_message_iter_get_basic(iter, &str);
 
-			DBG("static hostname: %s", str);
+			DBG("static hostname: '%s'", str);
 
 			g_free(static_hostname);
 			static_hostname = g_strdup(str);
@@ -165,7 +165,7 @@ static void property_changed(GDBusProxy *proxy, const char *name,
 
 			dbus_message_iter_get_basic(iter, &str);
 
-			DBG("chassis: %s", str);
+			DBG("chassis: '%s'", str);
 
 			for (i = 0; chassis_table[i].chassis; i++) {
 				if (strcmp(chassis_table[i].chassis, str))
-- 
2.37.3


From e2b2b1675f310023862319ea10ffd205a75cc0cb Mon Sep 17 00:00:00 2001
From: Bastien Nocera <hadess@hadess.net>
Date: Wed, 9 Nov 2022 16:17:56 +0100
Subject: [PATCH 2/2] hostname: Fallback to transient hostname

After pretty hostname, and static hostname, also support transient
hostname as a last resort before 'BlueZ X.XX'.

This happens on Fedora's Workstation installation as it calls
"hostnamectl set-hostname" on startup. In Fedora Silverblue, the default
hostname is set as fedora in /etc/os-release.

In both cases, we should fall back to that transient hostname, as bad as
it could be.

Note that the transient hostname needs to be monitored through the
kernel directly, as explained in:
https://www.freedesktop.org/software/systemd/man/org.freedesktop.hostname1.html
---
 plugins/hostname.c | 57 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 55 insertions(+), 2 deletions(-)

diff --git a/plugins/hostname.c b/plugins/hostname.c
index 14b6450b5..51707f07d 100644
--- a/plugins/hostname.c
+++ b/plugins/hostname.c
@@ -16,6 +16,8 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
+#include <fcntl.h>
+#include <sys/utsname.h>
 
 #include "lib/bluetooth.h"
 #include "lib/sdp.h"
@@ -44,8 +46,10 @@
 static uint8_t major_class = MAJOR_CLASS_MISCELLANEOUS;
 static uint8_t minor_class = MINOR_CLASS_UNCATEGORIZED;
 
-static char *pretty_hostname = NULL;
-static char *static_hostname = NULL;
+static char *pretty_hostname    = NULL;
+static char *static_hostname    = NULL;
+static char *transient_hostname = NULL;
+static guint hostname_id = 0;
 
 /*
  * Fallback to static hostname only if empty pretty hostname was already
@@ -60,6 +64,10 @@ static const char *get_hostname(void)
 		if (static_hostname &&
 				g_str_equal(static_hostname, "") == FALSE)
 			return static_hostname;
+
+		if (transient_hostname &&
+				g_str_equal(transient_hostname, "") == FALSE)
+			return transient_hostname;
 	}
 
 	return NULL;
@@ -181,6 +189,32 @@ static void property_changed(GDBusProxy *proxy, const char *name,
 	}
 }
 
+static void read_transient_hostname(void)
+{
+	struct utsname u;
+
+	if (uname(&u) != 0) {
+		g_free(transient_hostname);
+		transient_hostname = NULL;
+		DBG("failed to read transient hostname");
+		return;
+	}
+
+	g_free(transient_hostname);
+	transient_hostname = g_strdup(u.nodename);
+
+	DBG("read transient hostname: '%s'", transient_hostname);
+}
+
+static gboolean hostname_cb(GIOChannel *io, GIOCondition cond,
+							gpointer user_data)
+{
+	DBG("transient hostname changed");
+	read_transient_hostname();
+	adapter_foreach(update_class, NULL);
+	return TRUE;
+}
+
 static int hostname_probe(struct btd_adapter *adapter)
 {
 	DBG("");
@@ -261,9 +295,11 @@ static GDBusProxy *hostname_proxy = NULL;
 static int hostname_init(void)
 {
 	DBusConnection *conn = btd_get_dbus_connection();
+	int fd;
 	int err;
 
 	read_dmi_fallback();
+	read_transient_hostname();
 
 	hostname_client = g_dbus_client_new(conn, "org.freedesktop.hostname1",
 						"/org/freedesktop/hostname1");
@@ -289,6 +325,17 @@ static int hostname_init(void)
 		hostname_client = NULL;
 	}
 
+	fd = open("/proc/sys/kernel/hostname", O_RDONLY);
+	if (fd < 0) {
+		error("open(/proc/sys/kernel/hostname): %s (%d)",
+					strerror(errno), errno);
+	} else {
+		GIOChannel *io = g_io_channel_unix_new(fd);
+
+		hostname_id = g_io_add_watch(io, G_IO_ERR, hostname_cb, NULL);
+		g_io_channel_unref(io);
+	}
+
 	return err;
 }
 
@@ -306,8 +353,14 @@ static void hostname_exit(void)
 		hostname_client = NULL;
 	}
 
+	if (hostname_id != 0) {
+		g_source_remove(hostname_id);
+		hostname_id = 0;
+	}
+
 	g_free(pretty_hostname);
 	g_free(static_hostname);
+	g_free(transient_hostname);
 }
 
 BLUETOOTH_PLUGIN_DEFINE(hostname, VERSION, BLUETOOTH_PLUGIN_PRIORITY_DEFAULT,
-- 
2.37.3