This is the mail archive of the
newlib@sourceware.org
mailing list for the newlib project.
[PATCH] Add and use _REENT_GLOBAL_ATEXIT
- From: Sebastian Huber <sebastian dot huber at embedded-brains dot de>
- To: newlib at sourceware dot org
- Date: Wed, 1 May 2013 17:58:54 +0200
- Subject: [PATCH] Add and use _REENT_GLOBAL_ATEXIT
This patch adds a new define _REENT_GLOBAL_ATEXIT which will remove the
_atexit and _atexit0 fields of struct _reent. A global variable defined
in __atexit.c will be used to store the first 32 atexit() handlers. A
global variable in __call_atexit.c contains the LIFO head. This option
is interesting for all targets which don't care about binary
compatibility and want to save approximately 400 bytes per struct
_reent.
The usage of __register_exitproc() will pull in also __call_atexit.c but
not vice versa.
newlib/ChangeLog
2013-05-01 Sebastian Huber <sebastian.huber@embedded-brains.de>
* libc/include/sys/config.h (_REENT_GLOBAL_ATEXIT): Define for
RTEMS.
* libc/include/sys/reent.h (_ATEXIT_INIT): Define.
(_ATEXIT_INIT_PTR): Likewise.
(_REENT_INIT_ATEXIT): Likewise.
(_REENT_INIT_ATEXIT_PTR): Likewise.
(_REENT_ATEXIT): Likewise.
(struct _reent): Remove _atexit and _atexit0 fields if
_REENT_GLOBAL_ATEXIT is defined.
(_global_atexit): Declare if _REENT_GLOBAL_ATEXIT is defined.
* libc/reent/reent.c (_reclaim_reent): Use _REENT_GLOBAL_ATEXIT.
(_wrapup_reent): Likewise.
* libc/stdlib/__atexit.c (__atexit_lock): Declare.
(_global_atexit0): Define if _REENT_GLOBAL_ATEXIT is defined.
(_REENT_ATEXIT0): Define.
(__register_exitproc): Use _REENT_ATEXIT and _REENT_ATEXIT0.
* libc/stdlib/__call_atexit.c (__atexit_lock): Define.
(_global_atexit): Define if _REENT_GLOBAL_ATEXIT is defined.
(__call_exitprocs): Use _REENT_ATEXIT.
---
newlib/libc/include/sys/config.h | 1 +
newlib/libc/include/sys/reent.h | 46 +++++++++++++++++++++++++++++-------
newlib/libc/reent/reent.c | 17 +++++++++----
newlib/libc/stdlib/__atexit.c | 20 ++++++++++++----
newlib/libc/stdlib/__call_atexit.c | 10 ++++----
5 files changed, 72 insertions(+), 22 deletions(-)
diff --git a/newlib/libc/include/sys/config.h b/newlib/libc/include/sys/config.h
index a6528b8..b26017b 100644
--- a/newlib/libc/include/sys/config.h
+++ b/newlib/libc/include/sys/config.h
@@ -217,6 +217,7 @@
#if defined(__rtems__)
#define __FILENAME_MAX__ 255
#define _READ_WRITE_RETURN_TYPE _ssize_t
+#define _REENT_GLOBAL_ATEXIT
#endif
#ifndef __EXPORT
diff --git a/newlib/libc/include/sys/reent.h b/newlib/libc/include/sys/reent.h
index ff0242e..e3120a0 100644
--- a/newlib/libc/include/sys/reent.h
+++ b/newlib/libc/include/sys/reent.h
@@ -85,6 +85,12 @@ struct _atexit {
void (*_fns[_ATEXIT_SIZE])(void); /* the table itself */
struct _on_exit_args * _on_exit_args_ptr;
};
+# define _ATEXIT_INIT {_NULL, 0, {_NULL}, _NULL}
+# define _ATEXIT_INIT_PTR(var) \
+ (var)->_next = _NULL; \
+ (var)->_ind = 0; \
+ (var)->_fns[0] = _NULL; \
+ (var)->_on_exit_args_ptr = _NULL
#else
struct _atexit {
struct _atexit *_next; /* next in list */
@@ -93,6 +99,23 @@ struct _atexit {
void (*_fns[_ATEXIT_SIZE])(void); /* the table itself */
struct _on_exit_args _on_exit_args;
};
+# define _ATEXIT_INIT {_NULL, 0, {_NULL}, {{_NULL}, {_NULL}, 0, 0}}
+# define _ATEXIT_INIT_PTR(var) \
+ (var)->_next = _NULL; \
+ (var)->_ind = 0; \
+ (var)->_fns[0] = _NULL; \
+ (var)->_on_exit_args._fntypes = 0; \
+ (var)->_on_exit_args._fnargs[0] = _NULL
+#endif
+
+#ifdef _REENT_GLOBAL_ATEXIT
+# define _REENT_INIT_ATEXIT
+# define _REENT_INIT_ATEXIT_PTR(var, var0)
+#else
+# define _REENT_INIT_ATEXIT \
+ _NULL, _ATEXIT_INIT,
+# define _REENT_INIT_ATEXIT_PTR(var, var0) \
+ (var)->_atexit = _NULL; _ATEXIT_INIT_PTR(var0);
#endif
/*
@@ -392,9 +415,11 @@ struct _reent
/* signal info */
void (**(_sig_func))(int);
+# ifndef _REENT_GLOBAL_ATEXIT
/* atexit stuff */
struct _atexit *_atexit;
struct _atexit _atexit0;
+# endif
struct _glue __sglue; /* root of glue chain */
__FILE *__sf; /* file descriptors */
@@ -425,8 +450,7 @@ extern const struct __sFILE_fake __sf_fake_stderr;
_NULL, \
_NULL, \
_NULL, \
- _NULL, \
- {_NULL, 0, {_NULL}, _NULL}, \
+ _REENT_INIT_ATEXIT \
{_NULL, 0, _NULL}, \
_NULL, \
_NULL, \
@@ -452,11 +476,7 @@ extern const struct __sFILE_fake __sf_fake_stderr;
(var)->_localtime_buf = _NULL; \
(var)->_asctime_buf = _NULL; \
(var)->_sig_func = _NULL; \
- (var)->_atexit = _NULL; \
- (var)->_atexit0._next = _NULL; \
- (var)->_atexit0._ind = 0; \
- (var)->_atexit0._fns[0] = _NULL; \
- (var)->_atexit0._on_exit_args_ptr = _NULL; \
+ _REENT_INIT_ATEXIT_PTR(var, &(var)->_atexit0) \
(var)->__sglue._next = _NULL; \
(var)->__sglue._niobs = 0; \
(var)->__sglue._iobs = _NULL; \
@@ -641,9 +661,11 @@ struct _reent
} _unused;
} _new;
+# ifndef _REENT_GLOBAL_ATEXIT
/* atexit stuff */
struct _atexit *_atexit; /* points to head of LIFO stack */
struct _atexit _atexit0; /* one guaranteed table, required by ANSI */
+# endif
/* signal info */
void (**(_sig_func))(int);
@@ -698,8 +720,7 @@ struct _reent
{0, {0}} \
} \
}, \
- _NULL, \
- {_NULL, 0, {_NULL}, {{_NULL}, {_NULL}, 0, 0}}, \
+ _REENT_INIT_ATEXIT \
_NULL, \
{_NULL, 0, _NULL} \
}
@@ -791,6 +812,13 @@ void _reclaim_reent _PARAMS ((struct _reent *));
#define _GLOBAL_REENT _global_impure_ptr
+#ifdef _REENT_GLOBAL_ATEXIT
+extern struct _atexit *_global_atexit; /* points to head of LIFO stack */
+# define _REENT_ATEXIT(ptr) _global_atexit
+#else
+# define _REENT_ATEXIT(ptr) ((ptr)->_atexit)
+#endif
+
#ifdef __cplusplus
}
#endif
diff --git a/newlib/libc/reent/reent.c b/newlib/libc/reent/reent.c
index 63812db..61da3b2 100644
--- a/newlib/libc/reent/reent.c
+++ b/newlib/libc/reent/reent.c
@@ -87,10 +87,14 @@ _DEFUN (_reclaim_reent, (ptr),
_free_r (ptr, ptr->_localtime_buf);
if (ptr->_asctime_buf)
_free_r (ptr, ptr->_asctime_buf);
+#endif
+
+#ifndef _REENT_GLOBAL_ATEXIT
+ /* atexit stuff */
+# ifdef _REENT_SMALL
if (ptr->_atexit && ptr->_atexit->_on_exit_args_ptr)
_free_r (ptr, ptr->_atexit->_on_exit_args_ptr);
-#else
- /* atexit stuff */
+# else
if ((ptr->_atexit) && (ptr->_atexit != &ptr->_atexit0))
{
struct _atexit *p, *q;
@@ -101,6 +105,7 @@ _DEFUN (_reclaim_reent, (ptr),
_free_r (ptr, q);
}
}
+# endif
#endif
if (ptr->_cvtbuf)
@@ -131,19 +136,23 @@ _DEFUN (_reclaim_reent, (ptr),
void
_DEFUN (_wrapup_reent, (ptr), struct _reent *ptr)
{
+#ifndef _REENT_GLOBAL_ATEXIT
register struct _atexit *p;
+#endif
register int n;
if (ptr == NULL)
ptr = _REENT;
-#ifdef _REENT_SMALL
+#ifndef _REENT_GLOBAL_ATEXIT
+# ifdef _REENT_SMALL
for (p = ptr->_atexit, n = p ? p->_ind : 0; --n >= 0;)
(*p->_fns[n]) ();
-#else
+# else
for (p = ptr->_atexit; p; p = p->_next)
for (n = p->_ind; --n >= 0;)
(*p->_fns[n]) ();
+# endif
#endif
if (ptr->__cleanup)
(*ptr->__cleanup) (ptr);
diff --git a/newlib/libc/stdlib/__atexit.c b/newlib/libc/stdlib/__atexit.c
index 4687d00..b8104da 100644
--- a/newlib/libc/stdlib/__atexit.c
+++ b/newlib/libc/stdlib/__atexit.c
@@ -10,7 +10,17 @@
/* Make this a weak reference to avoid pulling in malloc. */
void * malloc(size_t) _ATTRIBUTE((__weak__));
-__LOCK_INIT_RECURSIVE(, __atexit_lock);
+
+#ifndef __SINGLE_THREAD__
+extern _LOCK_RECURSIVE_T __atexit_lock;
+#endif
+
+#ifdef _REENT_GLOBAL_ATEXIT
+static struct _atexit _global_atexit0 = _ATEXIT_INIT;
+# define _REENT_ATEXIT0(ptr) (&_global_atexit0)
+#else
+# define _REENT_ATEXIT0(ptr) (&(ptr)->_atexit0)
+#endif
/*
* Register a function to be performed at exit or on shared library unload.
@@ -31,9 +41,9 @@ _DEFUN (__register_exitproc,
__lock_acquire_recursive(__atexit_lock);
#endif
- p = _GLOBAL_REENT->_atexit;
+ p = _REENT_ATEXIT(_GLOBAL_REENT);
if (p == NULL)
- _GLOBAL_REENT->_atexit = p = &_GLOBAL_REENT->_atexit0;
+ _REENT_ATEXIT(_GLOBAL_REENT) = p = _REENT_ATEXIT0(_GLOBAL_REENT);
if (p->_ind >= _ATEXIT_SIZE)
{
#ifndef _ATEXIT_DYNAMIC_ALLOC
@@ -53,8 +63,8 @@ _DEFUN (__register_exitproc,
return -1;
}
p->_ind = 0;
- p->_next = _GLOBAL_REENT->_atexit;
- _GLOBAL_REENT->_atexit = p;
+ p->_next = _REENT_ATEXIT(_GLOBAL_REENT);
+ _REENT_ATEXIT(_GLOBAL_REENT) = p;
#ifndef _REENT_SMALL
p->_on_exit_args._fntypes = 0;
p->_on_exit_args._is_cxa = 0;
diff --git a/newlib/libc/stdlib/__call_atexit.c b/newlib/libc/stdlib/__call_atexit.c
index 4c45063..b30b843 100644
--- a/newlib/libc/stdlib/__call_atexit.c
+++ b/newlib/libc/stdlib/__call_atexit.c
@@ -11,8 +11,10 @@
/* Make this a weak reference to avoid pulling in free. */
void free(void *) _ATTRIBUTE((__weak__));
-#ifndef __SINGLE_THREAD__
-extern _LOCK_RECURSIVE_T __atexit_lock;
+__LOCK_INIT_RECURSIVE(, __atexit_lock);
+
+#ifdef _REENT_GLOBAL_ATEXIT
+struct _atexit *_global_atexit = _NULL;
#endif
#ifdef _WANT_REGISTER_FINI
@@ -78,8 +80,8 @@ _DEFUN (__call_exitprocs, (code, d),
restart:
- p = _GLOBAL_REENT->_atexit;
- lastp = &_GLOBAL_REENT->_atexit;
+ p = _REENT_ATEXIT(_GLOBAL_REENT);
+ lastp = &_REENT_ATEXIT(_GLOBAL_REENT);
while (p)
{
#ifdef _REENT_SMALL
--
1.7.10.4