[Mesa-dev] [Mesa-stable] [PATCH 4/4] glx: fix error code when there is no context bound

[Emil Velikov]

On 12 February 2016 at 05:34, Tapani Pälli <tapani.palli at intel.com> wrote:
> On 02/12/2016 02:54 AM, Emil Velikov wrote:
>>
>> On 11 February 2016 at 12:04, Tapani Pälli <tapani.palli at intel.com> wrote:
>>>
>>> From: Bernard Kilarski <bernard.r.kilarski at intel.com>
>>>
>>> Signed-off-by: Bernard Kilarski <bernard.r.kilarski at intel.com>
>>> Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
>>> Cc: "11.0 11.1" <mesa-stable at lists.freedesktop.org
>>> ---
>>>   src/glx/glxcmds.c                         | 2 +-
>>>   src/glx/query_renderer.c                  | 4 ++--
>>>   src/glx/tests/query_renderer_unittest.cpp | 4 ++++
>>>   3 files changed, 7 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c
>>> index 93e8db5..4db67ec 100644
>>> --- a/src/glx/glxcmds.c
>>> +++ b/src/glx/glxcmds.c
>>> @@ -1727,7 +1727,7 @@ __glXSwapIntervalSGI(int interval)
>>>      CARD32 *interval_ptr;
>>>      CARD8 opcode;
>>>
>>> -   if (gc == NULL) {
>>> +   if (gc == NULL || gc == &dummyContext) {
>>>         return GLX_BAD_CONTEXT;
>>>      }
>>>
>>> diff --git a/src/glx/query_renderer.c b/src/glx/query_renderer.c
>>> index 9108ec2..d49b8fe 100644
>>> --- a/src/glx/query_renderer.c
>>> +++ b/src/glx/query_renderer.c
>>> @@ -106,7 +106,7 @@ glXQueryCurrentRendererIntegerMESA(int attribute,
>>> unsigned int *value)
>>>   {
>>>      struct glx_context *gc = __glXGetCurrentContext();
>>>
>>> -   if (gc == NULL)
>>> +   if (gc == NULL || gc == &dummyContext)
>>>         return False;
>>>
>>>      return __glXQueryRendererInteger(gc->psc, attribute, value);
>>> @@ -166,7 +166,7 @@ glXQueryCurrentRendererStringMESA(int attribute)
>>>   {
>>>      struct glx_context *gc = __glXGetCurrentContext();
>>>
>>> -   if (gc == NULL)
>>> +   if (gc == NULL || gc == &dummyContext)
>>
>> Unless I'm missing something __glXGetCurrentContext() can never return
>> NULL, right ?
>
>
> This was my initial impression also ... but I'm not sure what happens here
> but unit tests (glx-test) for some reason completely explode if you take out
> the null check and try running 'make check'.
>
> I think that is why also the dummyContext is introduced in those tests. I
> played around a bit with this change and linking phase with glx-test starts
> to print quite weird errors, actually complete unrelated ones, I guess
> because it cannot find the 'extern' declared 'dummyContext'. I'm not sure if
> this is actually problem with the tests rather than this code.
>
Double checking - the tests are going crazy when you remove the null
check, even with the current/extra dummyContext ? That does sound
quite strange.

-Emil