swr: refactor swr_create_screen to allow for proper cleanup on error

This makes the following changes to address cleanup issues:
- Error conditions now return NULL instead of calling exit()
- swr_creen is now freed upon error, rather than leak.
- Library handle from dlopen is now closed upon swr_screen destruction

v2: Added additional context in commit msg and remove unnecessary "PUBLIC"
v3: Fix typo in commit message.

Signed-off-by: Chuck Atkins <[email protected]>
Reviewed-by: Emil Velikov <[email protected]>
Cc: Bruce Cherniak <[email protected]>
Cc: Tim Rowley <[email protected]>
cc: [email protected]

1 files changed, 5 insertions, 1 deletions

diff --git a/src/gallium/drivers/swr/swr_public.h b/src/gallium/drivers/swr/swr_public.h
index 4b150705cd7..07ea6280cd6 100644
--- a/src/gallium/drivers/swr/swr_public.h
+++ b/src/gallium/drivers/swr/swr_public.h
@@ -25,8 +25,9 @@
 #define SWR_PUBLIC_H
 
 struct pipe_screen;
-struct sw_winsys;
 struct sw_displaytarget;
+struct sw_winsys;
+struct swr_screen;
 
 #ifdef __cplusplus
 extern "C" {
@@ -38,6 +39,9 @@ struct pipe_screen *swr_create_screen(struct sw_winsys *winsys);
 // arch-specific dll entry point
 PUBLIC struct pipe_screen *swr_create_screen_internal(struct sw_winsys *winsys);
 
+// cleanup for failed screen creation
+void swr_destroy_screen_internal(struct swr_screen **screen);
+
 #ifdef _WIN32
 void swr_gdi_swap(struct pipe_screen *screen,
                   struct pipe_resource *res,