Attachment 113071 Details for Bug 46787 – 5/7] dbus-monitor: add support for using BecomeMonitor to be a read-only monitor

[patch] 5/7] dbus-monitor: add support for using BecomeMonitor to be a read-only monitor

0005-dbus-monitor-add-support-for-using-BecomeMonitor-to-.patch (text/plain), 3.76 KB, created by Simon McVittie on 2015-02-02 20:42:35 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Simon McVittie

Created: 2015-02-02 20:42:35 UTC

Size: 3.76 KB

patch

obsolete

>From 900b935f3e8481559609d0caa4b1c17345e85945 Mon Sep 17 00:00:00 2001
>From: Simon McVittie <simon.mcvittie@collabora.co.uk>
>Date: Mon, 2 Feb 2015 20:08:07 +0000
>Subject: [PATCH 5/7] dbus-monitor: add support for using BecomeMonitor to be a
> read-only monitor
>
>Move the dbus_connection_add_filter() call further up as a precaution,
>because it isn't safe for a monitor to not have a filter that
>swallows all messages.
>---
> tools/dbus-monitor.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 75 insertions(+), 9 deletions(-)
>
>diff --git a/tools/dbus-monitor.c b/tools/dbus-monitor.c
>index c15589a..5792112 100644
>--- a/tools/dbus-monitor.c
>+++ b/tools/dbus-monitor.c
>@@ -90,10 +90,9 @@ monitor_filter_func (DBusConnection     *connection,
>                               DBUS_INTERFACE_LOCAL,
>                               "Disconnected"))
>     exit (0);
>-  
>-  /* Conceptually we want this to be
>-   * DBUS_HANDLER_RESULT_NOT_YET_HANDLED, but this raises
>-   * some problems.  See bug 1719.
>+
>+  /* Monitors must not allow libdbus to reply to messages, so we eat
>+   * the message. See bug 1719.
>    */
>   return DBUS_HANDLER_RESULT_HANDLED;
> }
>@@ -236,6 +235,66 @@ only_one_type (dbus_bool_t *seen_bus_type,
>     }
> }
> 
>+static dbus_bool_t
>+become_monitor (DBusConnection *connection,
>+    int numFilters,
>+    const char * const *filters)
>+{
>+  DBusError error = DBUS_ERROR_INIT;
>+  DBusMessage *m;
>+  DBusMessage *r;
>+  int i;
>+  dbus_uint32_t zero = 0;
>+  DBusMessageIter appender, array_appender;
>+
>+  m = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
>+      DBUS_PATH_DBUS, DBUS_INTERFACE_MONITORING, "BecomeMonitor");
>+
>+  if (m == NULL)
>+    tool_oom ("becoming a monitor");
>+
>+  dbus_message_iter_init_append (m, &appender);
>+
>+  if (!dbus_message_iter_open_container (&appender, DBUS_TYPE_ARRAY, "s",
>+        &array_appender))
>+    tool_oom ("opening string array");
>+
>+  for (i = 0; i < numFilters; i++)
>+    {
>+      if (!dbus_message_iter_append_basic (&array_appender, DBUS_TYPE_STRING,
>+            &filters[i]))
>+        tool_oom ("adding filter to array");
>+    }
>+
>+  if (!dbus_message_iter_close_container (&appender, &array_appender) ||
>+      !dbus_message_iter_append_basic (&appender, DBUS_TYPE_UINT32, &zero))
>+    tool_oom ("finishing arguments");
>+
>+  r = dbus_connection_send_with_reply_and_block (connection, m, -1, &error);
>+
>+  if (r != NULL)
>+    {
>+      dbus_message_unref (r);
>+    }
>+  else if (dbus_error_has_name (&error, DBUS_ERROR_UNKNOWN_INTERFACE))
>+    {
>+      fprintf (stderr, "dbus-monitor: unable to enable new-style monitoring, "
>+          "your dbus-daemon is too old. Falling back to eavesdropping.\n");
>+      dbus_error_free (&error);
>+    }
>+  else
>+    {
>+      fprintf (stderr, "dbus-monitor: unable to enable new-style monitoring: "
>+          "%s: \"%s\". Falling back to eavesdropping.\n",
>+          error.name, error.message);
>+      dbus_error_free (&error);
>+    }
>+
>+  dbus_message_unref (m);
>+
>+  return (r != NULL);
>+}
>+
> int
> main (int argc, char *argv[])
> {
>@@ -359,7 +418,18 @@ main (int argc, char *argv[])
>       exit (1);
>     }
> 
>-  if (numFilters)
>+  if (!dbus_connection_add_filter (connection, filter_func, NULL, NULL))
>+    {
>+      fprintf (stderr, "Couldn't add filter!\n");
>+      exit (1);
>+    }
>+
>+  if (become_monitor (connection, numFilters,
>+                      (const char * const *) filters))
>+    {
>+      /* no more preparation needed */
>+    }
>+  else if (numFilters)
>     {
>       size_t offset = 0;
>       for (i = 0; i < j; i++)
>@@ -402,10 +472,6 @@ main (int argc, char *argv[])
>         }
>     }
> 
>-  if (!dbus_connection_add_filter (connection, filter_func, NULL, NULL)) {
>-    fprintf (stderr, "Couldn't add filter!\n");
>-    exit (1);
>-  }
> 
>   while (dbus_connection_read_write_dispatch(connection, -1))
>     ;
>-- 
>2.1.4
>

Actions: View | Splinter Review

Attachments on bug 46787: 112739 | 112740 | 112742 | 112743 | 112744 | 112745 | 112746 | 112747 | 112748 | 112749 | 112856 | 112857 | 112858 | 112859 | 112860 | 112861 | 113067 | 113068 | 113069 | 113070 | 113071 | 113072 | 113113 | 113114 | 113115 | 113116 | 113117 | 113118 | 113119 | 113120 | 113121 | 113161 | 113162 | 113163 | 113164

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.