From 214ff374545f433076515d80134dca7a1cdb991e Mon Sep 17 00:00:00 2001
From: Simon McVittie <simon.mcvittie@collabora.co.uk>
Date: Thu, 29 Nov 2012 16:20:03 +0000
Subject: [PATCH 6/6] Produce fake NameOwnerChanged signals that encode the
 pid of each peer

---
 bus/driver.c |   82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/bus/driver.c b/bus/driver.c
index 574e0f3..bc0a86b 100644
--- a/bus/driver.c
+++ b/bus/driver.c
@@ -241,6 +241,78 @@ create_unique_client_name (BusRegistry *registry,
   return TRUE;
 }
 
+#ifdef DBUS_ENABLE_CAPTURE
+static dbus_bool_t
+bus_driver_capture_pid (DBusConnection *connection,
+                        BusTransaction *transaction)
+{
+  DBusMessage *lie = NULL;
+  DBusString pid_name_buffer;
+  const char *pid_name;
+  const char *empty_name = "";
+  const char *unique_name;
+  unsigned long pid;
+
+  /* This is an entertaining hack suggested by the illustrious wjt.
+   * To profile a boot process or login, we want Bustle to show us process
+   * IDs. What it actually shows us are all our bus names. So... pretend
+   * the process had a bus name that contains its process ID. */
+
+  if (!dbus_connection_get_unix_process_id (connection, &pid))
+    {
+      /* Nothing useful we can do here. Do nothing, successfully. */
+      return TRUE;
+    }
+
+  if (!_dbus_string_init (&pid_name_buffer))
+    return FALSE;
+
+  lie = dbus_message_new_signal (DBUS_PATH_DBUS, DBUS_INTERFACE_DBUS,
+                                 "NameOwnerChanged");
+
+  if (lie == NULL)
+    goto oom;
+
+  if (!dbus_message_set_sender (lie, DBUS_SERVICE_DBUS))
+    goto oom;
+
+  if (!_dbus_string_append_printf (&pid_name_buffer,
+                                   "org.freedesktop.DBus.PcapHack.Process%lu",
+                                   pid))
+    goto oom;
+
+  pid_name = _dbus_string_get_const_data (&pid_name_buffer);
+
+  unique_name = bus_connection_get_name (connection);
+
+  if (!dbus_message_append_args (lie,
+                                 DBUS_TYPE_STRING, &pid_name,
+                                 DBUS_TYPE_STRING, &empty_name,
+                                 DBUS_TYPE_STRING, &unique_name,
+                                 DBUS_TYPE_INVALID))
+    goto oom;
+
+  _dbus_assert (dbus_message_has_signature (lie, "sss"));
+
+  /* Include the message in the transaction as if it had been sent, but do
+   * not actually send it. */
+  if (!bus_transaction_capture (transaction, lie))
+    goto oom;
+
+  _dbus_string_free (&pid_name_buffer);
+  dbus_message_unref (lie);
+  return TRUE;
+
+ oom:
+  if (lie != NULL)
+    dbus_message_unref (lie);
+
+  _dbus_string_free (&pid_name_buffer);
+
+  return FALSE;
+}
+#endif
+
 static dbus_bool_t
 bus_driver_handle_hello (DBusConnection *connection,
                          BusTransaction *transaction,
@@ -315,6 +387,16 @@ bus_driver_handle_hello (DBusConnection *connection,
   if (service == NULL)
     goto out_0;
 
+#ifdef DBUS_ENABLE_CAPTURE
+  /* This needs to happen after bus_registry_ensure() so the fake well-known
+   * name only appears after the unique name. */
+  if (!bus_driver_capture_pid (connection, transaction))
+    {
+      BUS_SET_OOM (error);
+      goto out_0;
+    }
+#endif
+
   _dbus_assert (bus_connection_is_active (connection));
   retval = TRUE;
 
-- 
1.7.10.4