1 files changed, 119 insertions, 0 deletions
diff --git a/nx-X11/util/memleak/stackbottom.c b/nx-X11/util/memleak/stackbottom.c
new file mode 100644
index 000000000..bd1a97a6a
--- /dev/null
+++ b/nx-X11/util/memleak/stackbottom.c
@@ -0,0 +1,119 @@
+/*
+ * cut and paste from gc 4.4 by Hans-J. Boehm and Alan J. Demers
+ *
+ * Cutter and Paster:  Jeffrey Hsu
+ */
+
+/* $XFree86: xc/util/memleak/stackbottom.c,v 3.1 1996/12/31 05:02:27 dawes Exp $ */
+
+#include <signal.h>
+
+typedef char * ptr_t;	/* A generic pointer to which we can add	*/
+			/* byte displacements.				*/
+			/* Preferably identical to caddr_t, if it 	*/
+			/* exists.					*/
+
+#ifndef bool
+typedef int bool;
+#endif
+
+#define VOLATILE volatile
+
+# ifndef STACK_GROWS_UP
+#   define STACK_GROWS_DOWN
+# endif
+
+typedef unsigned long word;
+
+#define TRUE 1
+
+#if defined(__alpha) || defined(__alpha__)
+    extern __start
+#   define HEURISTIC2_LIMIT ((ptr_t)((word)(&__start) & ~(getpagesize()-1)))
+#endif
+
+void GC_noop() {}
+
+  /* Some tools to implement HEURISTIC2	*/
+#   define MIN_PAGE_SIZE 256	/* Smallest conceivable page size, bytes */
+#   include <setjmp.h>
+    /* static */ jmp_buf GC_jmp_buf;
+    
+    /*ARGSUSED*/
+    void GC_fault_handler(sig)
+    int sig;
+    {
+        longjmp(GC_jmp_buf, 1);
+    }
+
+	typedef void (*handler)(int);
+
+    /* Return the first nonaddressible location > p (up) or 	*/
+    /* the smallest location q s.t. [q,p] is addressible (!up).	*/
+    ptr_t GC_find_limit(p, up)
+    ptr_t p;
+    bool up;
+    {
+        static VOLATILE ptr_t result;
+    		/* Needs to be static, since otherwise it may not be	*/
+    		/* preserved across the longjmp.  Can safely be 	*/
+    		/* static since it's only called once, with the		*/
+    		/* allocation lock held.				*/
+
+          static handler old_segv_handler, old_bus_handler;
+      		/* See above for static declaration.			*/
+
+    	  old_segv_handler = signal(SIGSEGV, GC_fault_handler);
+#	  ifdef SIGBUS
+	    old_bus_handler = signal(SIGBUS, GC_fault_handler);
+#	  endif
+	if (setjmp(GC_jmp_buf) == 0) {
+	    result = (ptr_t)(((word)(p))
+			      & ~(MIN_PAGE_SIZE-1));
+	    for (;;) {
+ 	        if (up) {
+		    result += MIN_PAGE_SIZE;
+ 	        } else {
+		    result -= MIN_PAGE_SIZE;
+ 	        }
+		GC_noop(*result);
+	    }
+	}
+  	  (void) signal(SIGSEGV, old_segv_handler);
+#	  ifdef SIGBUS
+	    (void) signal(SIGBUS, old_bus_handler);
+#	  endif
+ 	if (!up) {
+	    result += MIN_PAGE_SIZE;
+ 	}
+	return(result);
+    }
+
+ptr_t GC_get_stack_base()
+{
+    word dummy;
+    static ptr_t result;
+
+    if (!result) {
+
+#	    ifdef STACK_GROWS_DOWN
+		result = GC_find_limit((ptr_t)(&dummy), TRUE);
+#           	ifdef HEURISTIC2_LIMIT
+		    if (result > HEURISTIC2_LIMIT
+		        && (ptr_t)(&dummy) < HEURISTIC2_LIMIT) {
+		            result = HEURISTIC2_LIMIT;
+		    }
+#	        endif
+#	    else
+		result = GC_find_limit((ptr_t)(&dummy), FALSE);
+#           	ifdef HEURISTIC2_LIMIT
+		    if (result < HEURISTIC2_LIMIT
+		        && (ptr_t)(&dummy) > HEURISTIC2_LIMIT) {
+		            result = HEURISTIC2_LIMIT;
+		    }
+#	        endif
+#	    endif
+    }
+
+    	return(result);
+}