From: Stephen Adams <edu/mit/csail/zurich/adams>
Date: Sat, 7 Aug 1993 00:15:54 +0000 (+0000)
Subject: Fix for re-entrant foreign function: saves C stack & frame pointers
X-Git-Tag: 20090517-FFI~8117
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=33b14b6f0c236072e1783043b32c80afc75b2fef;p=mit-scheme.git

Fix for re-entrant foreign function: saves C stack & frame pointers
---

diff --git a/v7/src/microcode/utils.c b/v7/src/microcode/utils.c
index 0ba965548..51602f097 100644
--- a/v7/src/microcode/utils.c
+++ b/v7/src/microcode/utils.c
@@ -1,6 +1,6 @@
 /* -*-C-*-
 
-$Id: utils.c,v 9.60 1993/08/03 08:30:06 gjr Exp $
+$Id: utils.c,v 9.61 1993/08/07 00:15:54 adams Exp $
 
 Copyright (c) 1987-1993 Massachusetts Institute of Technology
 
@@ -1093,6 +1093,7 @@ extern SCHEME_OBJECT EXFUN (Re_Enter_Interpreter, (void));
 extern SCHEME_OBJECT EXFUN (C_call_scheme,
 			    (SCHEME_OBJECT, long, SCHEME_OBJECT *));
 
+
 SCHEME_OBJECT
 DEFUN (C_call_scheme, (proc, nargs, argvec),
        SCHEME_OBJECT proc
@@ -1100,6 +1101,11 @@ DEFUN (C_call_scheme, (proc, nargs, argvec),
        AND SCHEME_OBJECT * argvec)
 {
   SCHEME_OBJECT primitive, prim_lexpr, * sp, result;
+
+  extern void *C_Frame_Pointer, *C_Stack_Pointer;
+  void *cfp, *csp;
+  
+  cfp = C_Frame_Pointer, csp = C_Stack_Pointer;
   
   primitive = (Regs [REGBLOCK_PRIMITIVE]);
   prim_lexpr = (Regs [REGBLOCK_LEXPR_ACTUALS]);
@@ -1140,5 +1146,7 @@ DEFUN (C_call_scheme, (proc, nargs, argvec),
   Regs [REGBLOCK_LEXPR_ACTUALS] = prim_lexpr;
   Regs [REGBLOCK_PRIMITIVE] = primitive;
 
+  C_Frame_Pointer = cfp;
+  C_Stack_Pointer = csp;
   return (result);
 }