[PATCH] dbus: clean up new D-Bus interface getters and setters

[Chinchilla, Angie V]

> -----Original Message-----
> From: Dan Williams [mailto:dcbw at redhat.com]
> Sent: Wednesday, July 27, 2011 12:23 PM
> To: hostap at lists.shmoo.com
> Cc: Chinchilla, Angie V; Jouni Malinen
> Subject: [PATCH] dbus: clean up new D-Bus interface getters and setters
> 
> A number of fixes/improvements here:
> 
> 1) Remove casting of getter/setter function types which allows
> us to change the prototypes in the future and not have hard-to-find
> runtime segfaults
> 
> 2) Instead of having the getters create a fake reply message which
> then gets its arguments copied into the real reply message, and is
> then disposed, just pass message iters around and have them add
> their arguments to the message itself
> 
> 3) For setters, just pass in the message iter positioned at the
> start of the argument list, instead of each setter having to skip
> over the standard interface+property name
> 
> 4) Convert error handling to use DBusError and return the error
> back down through the call stacks to the function that will
> actually send the error back to the caller, instead of having a
> fake DBusMessage of type DBUS_MESSAGE_TYPE_ERROR that then
> needs to have the error extracted from it.
> 
> But most of all, this fixes various segfaults (like rh #725517
> and #678625) which were caused by some functions deep down in the
> getter callpaths wanting a source DBusMessage* when the getters were
> used for two things: signals (which don't have a source DBusMessage)
> and methods (which will have a source DBusMessage that's being
> replied to).  This duality made the code fragile when handling
> errors like invalid IEs over the air.
> 
> Signed-off-by: Dan Williams <dcbw at redhat.com>
> ---
>  wpa_supplicant/dbus/dbus_dict_helpers.c     |   14 +-
>  wpa_supplicant/dbus/dbus_dict_helpers.h     |    3 +-
>  wpa_supplicant/dbus/dbus_new.c              |  186 ++--
>  wpa_supplicant/dbus/dbus_new_handlers.c     | 1401 +++++++++++++------
> --------
>  wpa_supplicant/dbus/dbus_new_handlers.h     |  223 +++--
>  wpa_supplicant/dbus/dbus_new_handlers_p2p.c |  396 ++++----
>  wpa_supplicant/dbus/dbus_new_handlers_p2p.h |   73 +-
>  wpa_supplicant/dbus/dbus_new_handlers_wps.c |   32 +-
>  wpa_supplicant/dbus/dbus_new_helpers.c      |  366 ++++----
>  wpa_supplicant/dbus/dbus_new_helpers.h      |   17 +-
>  wpa_supplicant/dbus/dbus_old_handlers.c     |    8 +-
>  11 files changed, 1353 insertions(+), 1366 deletions(-)

Reviewed most of this and applied it and tested the scenarios that 
led to my related patch. It looks much cleaner and dbus programming 
errors should be easier to debug. Thanks!

-Angie