[Mesa-dev] [PATCH 10/14] i915: Validate API and version in i915CreateContext

[Kenneth Graunke]

On 08/08/2012 10:38 AM, Ian Romanick wrote:
> From: Ian Romanick <ian.d.romanick at intel.com>
> 
> Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
> ---
>  src/mesa/drivers/dri/i915/i915_context.c  |   35 ++++++++++++++++++++++++++++-
>  src/mesa/drivers/dri/i915/i915_context.h  |    3 ++
>  src/mesa/drivers/dri/intel/intel_screen.c |    4 +++
>  3 files changed, 41 insertions(+), 1 deletions(-)
> 
> diff --git a/src/mesa/drivers/dri/i915/i915_context.c b/src/mesa/drivers/dri/i915/i915_context.c
> index dc32292..0729479 100644
> --- a/src/mesa/drivers/dri/i915/i915_context.c
> +++ b/src/mesa/drivers/dri/i915/i915_context.c
> @@ -146,6 +146,9 @@ bool
>  i915CreateContext(int api,
>  		  const struct gl_config * mesaVis,
>                    __DRIcontext * driContextPriv,
> +                  unsigned major_version,
> +                  unsigned minor_version,
> +                  unsigned *error,
>                    void *sharedContextPrivate)
>  {
>     struct dd_function_table functions;
> @@ -153,8 +156,10 @@ i915CreateContext(int api,
>     struct intel_context *intel = &i915->intel;
>     struct gl_context *ctx = &intel->ctx;
>  
> -   if (!i915)
> +   if (!i915) {
> +      *error = __DRI_CTX_ERROR_NO_MEMORY;
>        return false;
> +   }
>  
>     i915InitVtbl(i915);
>  
> @@ -163,6 +168,34 @@ i915CreateContext(int api,
>     if (!intelInitContext(intel, api, mesaVis, driContextPriv,
>                           sharedContextPrivate, &functions)) {
>        FREE(i915);
> +      *error = __DRI_CTX_ERROR_NO_MEMORY;
> +      return false;
> +   }
> +
> +   /* Now that the extension bits are known, filter against the requested API
> +    * and version.
> +    */
> +   switch (api) {
> +   case API_OPENGL: {
> +      const unsigned max_version =
> +         (ctx->Extensions.ARB_fragment_shader
> +          && ctx->Extensions.ARB_occlusion_query)
> +         ? 0x200 : 0x105;
> +      const unsigned req_version = (major_version << 8) | minor_version;

Not the most readable of code.  I'd prefer:

   const unsigned max_version =
      (ctx->Extensions.ARB_fragment_shader &&
       ctx->Extensions.ARB_occlusion_query) ? 20 : 15;

   const unsigned requested_ver = major_version * 10 + minor_version;

That matches the style we use in ctx->Version.  Otherwise,
Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>

> +      if (req_version > max_version) {
> +         *error = __DRI_CTX_ERROR_BAD_VERSION;
> +         FREE(i915);
> +         return false;
> +      }
> +      break;
> +   }
> +   case API_OPENGLES:
> +   case API_OPENGLES2:
> +      break;
> +   default:
> +      *error = __DRI_CTX_ERROR_BAD_API;
> +      FREE(i915);
>        return false;
>     }
>  
> diff --git a/src/mesa/drivers/dri/i915/i915_context.h b/src/mesa/drivers/dri/i915/i915_context.h
> index 7037465..f5c1596 100644
> --- a/src/mesa/drivers/dri/i915/i915_context.h
> +++ b/src/mesa/drivers/dri/i915/i915_context.h
> @@ -322,6 +322,9 @@ do {									\
>  extern bool i915CreateContext(int api,
>  			      const struct gl_config * mesaVis,
>  			      __DRIcontext * driContextPriv,
> +                              unsigned major_version,
> +                              unsigned minor_version,
> +                              unsigned *error,
>  			      void *sharedContextPrivate);
>  
>  
> diff --git a/src/mesa/drivers/dri/intel/intel_screen.c b/src/mesa/drivers/dri/intel/intel_screen.c
> index 2fef8fe..bc8c265 100644
> --- a/src/mesa/drivers/dri/intel/intel_screen.c
> +++ b/src/mesa/drivers/dri/intel/intel_screen.c
> @@ -680,6 +680,9 @@ extern bool
>  i915CreateContext(int api,
>  		  const struct gl_config *mesaVis,
>  		  __DRIcontext *driContextPriv,
> +                  unsigned major_version,
> +                  unsigned minor_version,
> +                  unsigned *error,
>  		  void *sharedContextPrivate);
>  extern bool
>  brwCreateContext(int api,
> @@ -721,6 +724,7 @@ intelCreateContext(gl_api api,
>  #ifdef I915
>     if (IS_9XX(intelScreen->deviceID)) {
>        success = i915CreateContext(api, mesaVis, driContextPriv,
> +                                  major_version, minor_version, error,
>                                    sharedContextPrivate);
>     } else {
>        switch (api) {
>