Pre-validate ChangeGC XIDs.

In order to execute a wire-level ChangeGC request, we need to look up
the resources named by any XIDs in the value-list. Various places in the
server already have pointers to the resources they want to set into the
GC, though, so over time the interface has evolved to accept either XIDs
or pointers, with several different function call signatures used in
different eras.

This patch makes the existing code require pointers to resources rather
than XIDs, and adds a simple wrapper that looks up any XIDs. The old
dixChangeGC API is preserved by delegating to whichever implementation
is appropriate.

This affects error-handling: If any of the XIDs are invalid, then the GC
is unchanged, and its ChangeGC callback is not invoked. This change is
allowed by the protocol spec, which says, "The order in which components
are verified and altered is server-dependent. If an error is generated,
a subset of the components may have been altered."

Signed-off-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Keith Packard <keithp@keithp.com>

0 files changed, 0 insertions, 0 deletions