/*
* @(#)newlibc.c 1.9 - 95/05/16
*
*/
#if defined(RTEMS_NEWLIB)
/*
* File: newlibc.c,v
* Project: PixelFlow
* Created: 94/12/7
* Revision: 1.2
* Last Mod: 1995/05/09 20:24:37
*
* COPYRIGHT (c) 1994 by Division Incorporated
*
* To anyone who acknowledges that this file is provided "AS IS"
* without any express or implied warranty:
* permission to use, copy, modify, and distribute this file
* for any purpose is hereby granted without fee, provided that
* the above copyright notice and this notice appears in all
* copies, and that the name of Division Incorporated not be
* used in advertising or publicity pertaining to distribution
* of the software without specific, written prior permission.
* Division Incorporated makes no representations about the
* suitability of this software for any purpose.
*
* Description:
* Implementation of hooks for the CYGNUS newlib libc
* These hooks set things up so that:
* '_REENT' is switched at task switch time.
*
*
* TODO:
*
* NOTE:
*
* $Id$
*
*/
#include <rtems.h>
#include <libcsupport.h>
#include <stdlib.h> /* for free() */
#include <string.h> /* for memset() */
#include <sys/reent.h> /* for extern of _REENT (aka _impure_ptr) */
#include "internal.h"
#define LIBC_NOTEPAD RTEMS_NOTEPAD_LAST
int libc_reentrant; /* do we think we are reentrant? */
struct _reent libc_global_reent = _REENT_INIT(libc_global_reent);;
/*
* CYGNUS newlib routine that does atexit() processing and flushes
* stdio streams
* undocumented
*/
extern void _wrapup_reent(struct _reent *);
extern void _reclaim_reent(struct _reent *);
void
libc_wrapup(void)
{
_wrapup_reent(0);
if (_REENT != &libc_global_reent)
{
_wrapup_reent(&libc_global_reent);
#if 0
/* don't reclaim this one, just in case we do printfs */
/* on our way out to ROM */
_reclaim_reent(&libc_global_reent);
#endif
_REENT = &libc_global_reent;
}
}
rtems_boolean
libc_create_hook(rtems_tcb *current_task,
rtems_tcb *creating_task)
{
MY_task_set_note(creating_task, LIBC_NOTEPAD, 0);
return TRUE;
}
/*
* Called for all user TASKS (system tasks are SYSI and IDLE)
*/
rtems_extension
libc_start_hook(rtems_tcb *current_task,
rtems_tcb *starting_task)
{
struct _reent *ptr;
/* NOTE: our malloc is reentrant without a reent ptr since
* it is based on region manager
*/
ptr = (struct _reent *) malloc(sizeof(struct _reent));
/* GCC extension: structure constants */
*ptr = (struct _reent) _REENT_INIT((*ptr));
MY_task_set_note(starting_task, LIBC_NOTEPAD, (rtems_unsigned32) ptr);
}
rtems_extension
libc_switch_hook(rtems_tcb *current_task,
rtems_tcb *heir_task)
{
rtems_unsigned32 impure_value;
/* XXX We can't use rtems_task_set_note() here since SYSI task has a
* tid of 0, which is treated specially (optimized, actually)
* by rtems_task_set_note
*/
impure_value = (rtems_unsigned32) _REENT;
MY_task_set_note(current_task, LIBC_NOTEPAD, impure_value);
_REENT = (struct _reent *) MY_task_get_note(heir_task, LIBC_NOTEPAD);
}
/*
* Function: libc_delete_hook
* Created: 94/12/10
*
* Description:
* Called when a task is deleted.
* Must restore the new lib reentrancy state for the new current
* task.
*
* Parameters:
*
*
* Returns:
*
*
* Side Effects:
*
* Notes:
*
*
* Deficiencies/ToDo:
*
*
*/
rtems_extension
libc_delete_hook(rtems_tcb *current_task,
rtems_tcb *deleted_task)
{
struct _reent *ptr;
/*
* The reentrancy structure was allocated by newlib using malloc()
*/
if (current_task == deleted_task)
{
ptr = _REENT;
}
else
{
ptr = (struct _reent *) MY_task_get_note(deleted_task, LIBC_NOTEPAD);
}
if (ptr)
{
_wrapup_reent(ptr);
_reclaim_reent(ptr);
}
MY_task_set_note(deleted_task, LIBC_NOTEPAD, 0);
/*
* Require the switch back to another task to install its own
*/
if (current_task == deleted_task)
{
_REENT = 0;
}
}
/*
* Function: libc_init
* Created: 94/12/10
*
* Description:
* Init libc for CYGNUS newlib
* Set up _REENT to use our global libc_global_reent.
* (newlib provides a global of its own, but we prefer our
* own name for it)
*
* If reentrancy is desired (which it should be), then
* we install the task extension hooks to maintain the
* newlib reentrancy global variable _REENT on task
* create, delete, switch, exit, etc.
*
* Parameters:
* reentrant non-zero if reentrant library desired.
*
* Returns:
*
* Side Effects:
* installs libc extensions if reentrant.
*
* Notes:
*
*
* Deficiencies/ToDo:
*
*/
void
libc_init(int reentrant)
{
rtems_extensions_table libc_extension;
rtems_id extension_id;
rtems_status_code rc;
_REENT = &libc_global_reent;
if (reentrant)
{
memset(&libc_extension, 0, sizeof(libc_extension));
libc_extension.thread_create = libc_create_hook;
libc_extension.thread_start = libc_start_hook;
libc_extension.thread_switch = libc_switch_hook;
libc_extension.thread_delete = libc_delete_hook;
rc = rtems_extension_create(rtems_build_name('L', 'I', 'B', 'C'),
&libc_extension, &extension_id);
if (rc != RTEMS_SUCCESSFUL)
rtems_fatal_error_occurred(rc);
libc_reentrant = reentrant;
}
}
void
exit(int status)
{
libc_wrapup();
rtems_shutdown_executive(status);
}
/*
* Function: _exit
* Created: 94/12/10
*
* Description:
* Called from exit() after it does atexit() processing and stdio fflush's
*
* called from bottom of exit() to really delete the task.
* If we are using reentrant libc, then let the delete extension
* do all the work, otherwise if a shutdown is in progress,
* then just do it.
*
* Parameters:
* exit status
*
* Returns:
* does not return
*
* Side Effects:
*
* Notes:
*
*
* Deficiencies/ToDo:
*
*
*/
#if !defined(RTEMS_UNIX) && !defined(__GO32__)
void _exit(int status)
{
rtems_shutdown_executive(status);
}
#endif
#endif
