Mesa (master): vbo: fix glPrimitiveRestartNV crash inside a display list

[Brian Paul]

Module: Mesa
Branch: master
Commit: f5c8bb1e00f358e05ed21f8ed69c9fc3803bf95f
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=f5c8bb1e00f358e05ed21f8ed69c9fc3803bf95f

Author: Olivier Lauffenburger <o.lauffenburger at topsolid.com>
Date:   Thu Jul  6 09:45:00 2017 -0600

vbo: fix glPrimitiveRestartNV crash inside a display list

glPrimitiveRestartNV crashes when it is called during the compilation
of a display list.

There are two reasons:
- ctx->Driver.CurrentSavePrimitive is not set to the current primitive
- save_PrimitiveRestartNV() calls _save_Begin() which only sets an
  OpenGL error, instead of calling vbo_save_NotifyBegin().

This patch correctly calls vbo_save_NotifyBegin() but it detects
the current primitive mode by looking at the latest saved primitive.

Additional work by Brian Paul

Signed-off-by: Olivier Lauffenburger <o.lauffenburger at topsolid.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101464
Reviewed-by: Brian Paul <brianp at vmware.com>
Reviewed-by: Charmaine Lee <charmainel at vmware.com>

---

 src/mesa/vbo/vbo_save_api.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/mesa/vbo/vbo_save_api.c b/src/mesa/vbo/vbo_save_api.c
index a42a3c3db7..aab5f549d7 100644
--- a/src/mesa/vbo/vbo_save_api.c
+++ b/src/mesa/vbo/vbo_save_api.c
@@ -1108,13 +1108,23 @@ _save_Begin(GLenum mode)
 static void GLAPIENTRY
 _save_PrimitiveRestartNV(void)
 {
-   GLenum curPrim;
    GET_CURRENT_CONTEXT(ctx);
+   struct vbo_save_context *save = &vbo_context(ctx)->save;
 
-   curPrim = ctx->Driver.CurrentSavePrimitive;
-
-   _save_End();
-   _save_Begin(curPrim);
+   if (save->prim_count == 0) {
+      /* We're not inside a glBegin/End pair, so calling glPrimitiverRestartNV
+       * is an error.
+       */
+      _mesa_compile_error(ctx, GL_INVALID_OPERATION,
+                          "glPrimitiveRestartNV called outside glBegin/End");
+   } else {
+      /* get current primitive mode */
+      GLenum curPrim = save->prim[save->prim_count - 1].mode;
+
+      /* restart primitive */
+      CALL_End(GET_DISPATCH(), ());
+      vbo_save_NotifyBegin(ctx, curPrim);
+   }
 }