[Mesa-dev] [PATCH 04/14] glx: Add an optional function call for getting the DRI driver interface.

[Matt Turner]

On Mon, Sep 30, 2013 at 1:44 PM, Eric Anholt <eric at anholt.net> wrote:
> The previous interface relied on a static struct, which meant tha the
> driver didn't get a chance to edit the struct before the struct got used.
> For megadrivers, I want to return a variable struct based on what driver
> is getting loaded.
> ---
>  include/GL/internal/dri_interface.h | 13 +++++++++++++
>  src/glx/dri2_glx.c                  |  2 +-
>  src/glx/dri_common.c                | 18 +++++++++++++++++-
>  src/glx/dri_common.h                |  3 ++-
>  src/glx/dri_glx.c                   |  2 +-
>  src/glx/drisw_glx.c                 |  6 ++----
>  6 files changed, 36 insertions(+), 8 deletions(-)
>
> diff --git a/include/GL/internal/dri_interface.h b/include/GL/internal/dri_interface.h
> index 5c53d6e..93b6c0b 100644
> --- a/include/GL/internal/dri_interface.h
> +++ b/include/GL/internal/dri_interface.h
> @@ -488,6 +488,19 @@ struct __DRIuseInvalidateExtensionRec {
>  #define __DRI_DRIVER_EXTENSIONS "__driDriverExtensions"
>
>  /**
> + * This symbol replaces the __DRI_DRIVER_EXTENSIONS symbol, and will be
> + * suffixed by "_drivername", allowing multiple drivers to be built into one
> + * library, and also giving the driver the chance to return a variable driver
> + * extensions struct depending on the driver name being loaded or any other
> + * system state.
> + *
> + * The function prototype is:
> + *
> + * const __DRIextension **__driDriverGetExtensions(const char *name);
> + */
> +#define __DRI_DRIVER_GET_EXTENSIONS "__driDriverGetExtensions"
> +
> +/**
>   * Tokens for __DRIconfig attribs.  A number of attributes defined by
>   * GLX or EGL standards are not in the table, as they must be provided
>   * by the loader.  For example, FBConfig ID or visual ID, drawable type.
> diff --git a/src/glx/dri2_glx.c b/src/glx/dri2_glx.c
> index 123c87c..7e22906 100644
> --- a/src/glx/dri2_glx.c
> +++ b/src/glx/dri2_glx.c
> @@ -1183,7 +1183,7 @@ dri2CreateScreen(int screen, struct glx_display * priv)
>        goto handle_error;
>     }
>
> -   extensions = driGetDriverExtensions(psc->driver);
> +   extensions = driGetDriverExtensions(psc->driver, driverName);
>     if (extensions == NULL)
>        goto handle_error;
>
> diff --git a/src/glx/dri_common.c b/src/glx/dri_common.c
> index f1d1164..16f820f 100644
> --- a/src/glx/dri_common.c
> +++ b/src/glx/dri_common.c
> @@ -188,9 +188,25 @@ driOpenDriver(const char *driverName)
>  }
>
>  _X_HIDDEN const __DRIextension **
> -driGetDriverExtensions(void *handle)
> +driGetDriverExtensions(void *handle, const char *driver_name)
>  {
>     const __DRIextension **extensions = NULL;
> +   const __DRIextension **(*get_extensions)(void);
> +   char *get_extensions_name;
> +
> +   asprintf(&get_extensions_name, "%s_%s",
> +            __DRI_DRIVER_GET_EXTENSIONS, driver_name);

My gcc complains about this:

dri_common.c: In function 'driGetDriverExtensions':
dri_common.c:197:12: warning: ignoring return value of 'asprintf',
declared with attribute warn_unused_result [-Wunused-result]
    asprintf(&get_extensions_name, "%s_%s",
            ^

Kind of silly, but whatever.