[VDPAU] [PATCHv3] Add VDPAU_DRIVER_PATH support

[Stephen Warren]

Emil Velikov wrote at Thursday, February 20, 2014 3:38 PM:
> Allow the user to specify the location of the backend driver,
> via the VDPAU_DRIVER_PATH environment variable. This allows
> easier testing of VDPAU backends without the need to rebuild
> libvdpau.
> 
> Inspired by LIBGL_DRIVERS_PATH from mesa.

> diff --git a/src/vdpau_wrapper.c b/src/vdpau_wrapper.c

> +    /* Fallback to VDPAU_MODULEDIR when VDPAU_DRIVER_PATH is not set,
> +     * or if we fail to create the driver path/dlopen the library. */
> +    if (!_vdp_driver_dll &&
> +        snprintf(vdpau_driver_lib, sizeof(vdpau_driver_lib), DRIVER_LIB_FORMAT,
> +                 VDPAU_MODULEDIR, vdpau_driver) >=
>              sizeof(vdpau_driver_lib)) {
>          fprintf(stderr, "Failed to construct driver path: path too long\n");
>          if (vdpau_driver_dri2) {
> @@ -132,12 +149,14 @@ static VdpStatus _vdp_open_driver(
>          return VDP_STATUS_NO_IMPLEMENTATION;
>      }
> 
> -    _vdp_driver_dll = dlopen(vdpau_driver_lib, RTLD_NOW | RTLD_GLOBAL);
> +    if (!_vdp_driver_dll) {
> +        _vdp_driver_dll = dlopen(vdpau_driver_lib, RTLD_NOW | RTLD_GLOBAL);
> +    }

That should really be the following:

+    if (!_vdp_driver_dll) {
... existing sprint and dlopen code indented 1 level
+    }

With the patch as it is right now, that if condition is replicated in two
places:

if (!_vdp_driver_dll && sprint_ok) {
}
if (!_vdp_driver_dll) {
}

... which makes the logic unclear.

-- 
nvpublic