diff options
Diffstat (limited to 'gcc-4.7/gcc/ada/s-stchop-vxworks.adb')
| -rw-r--r-- | gcc-4.7/gcc/ada/s-stchop-vxworks.adb | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/gcc-4.7/gcc/ada/s-stchop-vxworks.adb b/gcc-4.7/gcc/ada/s-stchop-vxworks.adb new file mode 100644 index 000000000..ffdba814a --- /dev/null +++ b/gcc-4.7/gcc/ada/s-stchop-vxworks.adb @@ -0,0 +1,153 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- +-- -- +-- S Y S T E M . S T A C K _ C H E C K I N G . O P E R A T I O N S -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1999-2009, Free Software Foundation, Inc. -- +-- -- +-- GNARL is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 3, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- You should have received a copy of the GNU General Public License and -- +-- a copy of the GCC Runtime Library Exception along with this program; -- +-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- +-- <http://www.gnu.org/licenses/>. -- +-- -- +-- GNARL was developed by the GNARL team at Florida State University. -- +-- Extensive contributions were provided by Ada Core Technologies, Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This is the verson for VxWorks 5 and VxWorks MILS + +-- This file should be kept synchronized with the general implementation +-- provided by s-stchop.adb. + +pragma Restrictions (No_Elaboration_Code); +-- We want to guarantee the absence of elaboration code because the +-- binder does not handle references to this package. + +with System.Storage_Elements; use System.Storage_Elements; +with System.Parameters; use System.Parameters; +with Interfaces.C; + +package body System.Stack_Checking.Operations is + + -- In order to have stack checking working appropriately on VxWorks we need + -- to extract the stack size information from the VxWorks kernel itself. + + -- For VxWorks 5 the library for showing task-related information needs to + -- be linked into the VxWorks system, when using stack checking. The + -- taskShow library can be linked into the VxWorks system by either: + + -- * defining INCLUDE_SHOW_ROUTINES in config.h when using + -- configuration header files, or + + -- * selecting INCLUDE_TASK_SHOW when using the Tornado project + -- facility. + + -- VxWorks MILS includes the necessary routine in taskLib, so nothing + -- special needs to be done there. + + Stack_Limit : Address := + Boolean'Pos (Stack_Grows_Down) * Address'First + + Boolean'Pos (not Stack_Grows_Down) * Address'Last; + pragma Export (C, Stack_Limit, "__gnat_stack_limit"); + -- Stack_Limit contains the limit of the stack. This variable is later made + -- a task variable (by calling taskVarAdd) and then correctly set to the + -- stack limit of the task. Before being so initialized its value must be + -- valid so that any subprogram with stack checking enabled will run. We + -- use extreme values according to the direction of the stack. + + type Set_Stack_Limit_Proc_Acc is access procedure; + pragma Convention (C, Set_Stack_Limit_Proc_Acc); + + Set_Stack_Limit_Hook : Set_Stack_Limit_Proc_Acc; + pragma Import (C, Set_Stack_Limit_Hook, "__gnat_set_stack_limit_hook"); + -- Procedure to be called when a task is created to set stack + -- limit. + + procedure Set_Stack_Limit_For_Current_Task; + pragma Convention (C, Set_Stack_Limit_For_Current_Task); + -- Register Initial_SP as the initial stack pointer value for the current + -- task when it starts and Size as the associated stack area size. This + -- should be called once, after the soft-links have been initialized? + + ----------------------------- + -- Initialize_Stack_Limit -- + ----------------------------- + + procedure Initialize_Stack_Limit is + begin + -- For the environment task + + Set_Stack_Limit_For_Current_Task; + + -- Will be called by every created task + + Set_Stack_Limit_Hook := Set_Stack_Limit_For_Current_Task'Access; + end Initialize_Stack_Limit; + + -------------------------------------- + -- Set_Stack_Limit_For_Current_Task -- + -------------------------------------- + + procedure Set_Stack_Limit_For_Current_Task is + use Interfaces.C; + + function Task_Var_Add (Tid : Interfaces.C.int; Var : Address) + return Interfaces.C.int; + pragma Import (C, Task_Var_Add, "taskVarAdd"); + -- Import from VxWorks + + type OS_Stack_Info is record + Size : Interfaces.C.int; + Base : System.Address; + Limit : System.Address; + end record; + pragma Convention (C, OS_Stack_Info); + -- Type representing the information that we want to extract from the + -- underlying kernel. + + procedure Get_Stack_Info (Stack : not null access OS_Stack_Info); + pragma Import (C, Get_Stack_Info, "__gnat_get_stack_info"); + -- Procedure that fills the stack information associated to the + -- currently executing task. + + Stack_Info : aliased OS_Stack_Info; + + Limit : System.Address; + + begin + -- Get stack bounds from VxWorks + + Get_Stack_Info (Stack_Info'Access); + + -- In s-stchop.adb, we check for overflow in the following operations, + -- but we have no such check in this vxworks version. Why not ??? + + if Stack_Grows_Down then + Limit := Stack_Info.Base - Storage_Offset (Stack_Info.Size); + else + Limit := Stack_Info.Base + Storage_Offset (Stack_Info.Size); + end if; + + -- Note: taskVarAdd implicitly calls taskVarInit if required + + if Task_Var_Add (0, Stack_Limit'Address) = 0 then + Stack_Limit := Limit; + end if; + end Set_Stack_Limit_For_Current_Task; + +end System.Stack_Checking.Operations; |