Avoid clipping stack overruns in OpenGL graphics driver

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@11018 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 10 insertions, 0 deletions

diff --git a/src/Fl_Gl_Window.cxx b/src/Fl_Gl_Window.cxx
index e74065ac6..82b38fd14 100644
--- a/src/Fl_Gl_Window.cxx
+++ b/src/Fl_Gl_Window.cxx
@@ -187,6 +187,8 @@ public:
   }
   void push_clip(int x, int y, int w, int h) {
     // TODO: implement OpenGL clipping
+    if (rstackptr < region_stack_max) rstack[++rstackptr] = 0L;
+    else Fl::warning("Fl_OpenGL_Graphics_Driver::push_clip: clip stack overflow!\n");
   }
   int clip_box(int x, int y, int w, int h, int &X, int &Y, int &W, int &H) {
     // TODO: implement OpenGL clipping
@@ -199,12 +201,20 @@ public:
   }
   void push_no_clip() {
     // TODO: implement OpenGL clipping
+    if (rstackptr < region_stack_max) rstack[++rstackptr] = 0;
+    else Fl::warning("Fl_OpenGL_Graphics_Driver::push_no_clip: clip stack overflow!\n");
+    restore_clip();
   }
   void pop_clip() {
     // TODO: implement OpenGL clipping
+    if (rstackptr > 0) {
+      rstackptr--;
+    } else Fl::warning("Fl_OpenGL_Graphics_Driver::pop_clip: clip stack underflow!\n");
+    restore_clip();
   }
   void restore_clip() {
     // TODO: implement OpenGL clipping
+    fl_clip_state_number++;
   }
 };