1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/s390/backtrace.c b/sysdeps/s390/backtrace.c
new file mode 100644
index 0000000000..5e7f802810
--- /dev/null
+++ b/sysdeps/s390/backtrace.c
@@ -0,0 +1,81 @@
+/* Return backtrace of current program state.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <execinfo.h>
+#include <stddef.h>
+
+/* This is a global variable set at program start time.  It marks the
+   highest used stack address.  */
+extern void *__libc_stack_end;
+
+
+/* This is the stack layout we see for every non-leaf function.
+           size                    offset
+    %r15 ->    +------------------+
+             4 | back chain       |  0
+             4 | end of stack     |  4
+             8 | glue             |  8
+             8 | scratch          | 16
+            40 | save area r6-r15 | 24
+            16 | save area f4,f6  | 64
+            16 | empty            | 80
+               +------------------+
+   r14 in the save area holds the return address.
+*/
+
+struct layout
+{
+  int back_chain;
+  int end_of_stack;
+  int glue[2];
+  int scratch[2];
+  int save_grps[10];
+  int save_fp[4];
+  int empty[2];
+};
+
+int
+__backtrace (array, size)
+     void **array;
+     int size;
+{
+  /* We assume that all the code is generated with frame pointers set.  */
+  struct layout *stack;
+  int cnt = 0;
+
+  asm ("LR  %0,%%r15" : "=d" (stack) );
+  /* We skip the call to this function, it makes no sense to record it.  */
+  stack = (struct layout *) stack->back_chain;
+  while (cnt < size)
+    {
+      if (stack == NULL || (void *) stack > __libc_stack_end)
+	/* This means the address is out of range.  Note that for the
+	   toplevel we see a frame pointer with value NULL which clearly is
+	   out of range.  */
+	break;
+
+      array[cnt++] = stack->save_grps[9];
+
+      stack = (struct layout *) stack->back_chain;
+    }
+
+  return cnt;
+}
+weak_alias (__backtrace, backtrace)