[PATCH] Disable thread cancellation support for RTEMS

[Sebastian Huber]

Use a define to manage the stdio thread cancellation support.  Disable
the thread cancellation support for RTEMS.  In RTEMS the availability of
POSIX threads is optional and depends on a configuration option.  To
support all RTEMS configurations we have to drop the thread cancellation
support.  A long term solution has to be developed in RTEMS to deal with
this.  Once this is done, we can enable the support in Newlib again.

It seems that the Newlib locks are missing in general on RTEMS:

https://www.rtems.org/bugzilla/show_bug.cgi?id=1247

newlib/ChangeLog
2013-03-22  Sebastian Huber <sebastian.huber@embedded-brains.de>

	* libc/stdio/local.h (_STDIO_WITH_THREAD_CANCELLATION_SUPPORT):
	New define.
	* libc/stdio/fclose.c: Use
	_STDIO_WITH_THREAD_CANCELLATION_SUPPORT.
	* libc/stdio/freopen.c: Likewise.
	* libc/stdio64/freopen64.c: Likewise.
---
 newlib/libc/stdio/fclose.c      |    6 +++---
 newlib/libc/stdio/freopen.c     |    8 ++++----
 newlib/libc/stdio/local.h       |   11 ++++++++---
 newlib/libc/stdio64/freopen64.c |    4 ++--
 4 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/newlib/libc/stdio/fclose.c b/newlib/libc/stdio/fclose.c
index 7904964..fd054fe 100644
--- a/newlib/libc/stdio/fclose.c
+++ b/newlib/libc/stdio/fclose.c
@@ -78,7 +78,7 @@ _DEFUN(_fclose_r, (rptr, fp),
 
   /* We can't use the _newlib_flockfile_XXX macros here due to the
      interlocked locking with the sfp_lock. */
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
   int __oldcancel;
   pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &__oldcancel);
 #endif
@@ -87,7 +87,7 @@ _DEFUN(_fclose_r, (rptr, fp),
   if (fp->_flags == 0)		/* not open! */
     {
       _funlockfile (fp);
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
       pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
       return (0);
@@ -112,7 +112,7 @@ _DEFUN(_fclose_r, (rptr, fp),
 #endif
 
   __sfp_lock_release ();
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
   pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
 
diff --git a/newlib/libc/stdio/freopen.c b/newlib/libc/stdio/freopen.c
index b33eb1e..884e561 100644
--- a/newlib/libc/stdio/freopen.c
+++ b/newlib/libc/stdio/freopen.c
@@ -102,7 +102,7 @@ _DEFUN(_freopen_r, (ptr, file, mode, fp),
 
   /* We can't use the _newlib_flockfile_XXX macros here due to the
      interlocked locking with the sfp_lock. */
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
   int __oldcancel;
   pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &__oldcancel);
 #endif
@@ -111,7 +111,7 @@ _DEFUN(_freopen_r, (ptr, file, mode, fp),
   if ((flags = __sflags (ptr, mode, &oflags)) == 0)
     {
       _funlockfile (fp);
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
       pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
       _fclose_r (ptr, fp);
@@ -222,7 +222,7 @@ _DEFUN(_freopen_r, (ptr, file, mode, fp),
       __lock_close_recursive (fp->_lock);
 #endif
       __sfp_lock_release ();
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
       pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
       return NULL;
@@ -242,7 +242,7 @@ _DEFUN(_freopen_r, (ptr, file, mode, fp),
 #endif
 
   _funlockfile (fp);
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
   pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
   return fp;
diff --git a/newlib/libc/stdio/local.h b/newlib/libc/stdio/local.h
index b4bc5e0..58a16bd 100644
--- a/newlib/libc/stdio/local.h
+++ b/newlib/libc/stdio/local.h
@@ -45,7 +45,12 @@
    section before reaching the end of the critical section's code end, use
    the appropriate _newlib_XXX_exit macro. */
 
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS) \
+    && !defined (__rtems__)
+#define _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
+#endif
+
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
 #include <pthread.h>
 
 /* Start a stream oriented critical section: */
@@ -84,7 +89,7 @@
 	  pthread_setcancelstate (__oldsfpcancel, &__oldsfpcancel); \
 	}
 
-#else /* __SINGLE_THREAD__ || !_POSIX_THREADS */
+#else /* !_STDIO_WITH_THREAD_CANCELLATION_SUPPORT */
 
 # define _newlib_flockfile_start(_fp) \
 	{ \
@@ -108,7 +113,7 @@
 		__sfp_lock_release (); \
 	}
 
-#endif /* !__SINGLE_THREAD__ && _POSIX_THREADS */
+#endif /* _STDIO_WITH_THREAD_CANCELLATION_SUPPORT */
 
 extern u_char *_EXFUN(__sccl, (char *, u_char *fmt));
 extern int    _EXFUN(__svfscanf_r,(struct _reent *,FILE *, _CONST char *,va_list));
diff --git a/newlib/libc/stdio64/freopen64.c b/newlib/libc/stdio64/freopen64.c
index db0e1ee..dfe36ea 100644
--- a/newlib/libc/stdio64/freopen64.c
+++ b/newlib/libc/stdio64/freopen64.c
@@ -102,7 +102,7 @@ _DEFUN (_freopen64_r, (ptr, file, mode, fp),
 
   /* We can't use the _newlib_flockfile_XXX macros here due to the
      interlocked locking with the sfp_lock. */
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
   int __oldcancel;
   pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &__oldcancel);
 #endif
@@ -111,7 +111,7 @@ _DEFUN (_freopen64_r, (ptr, file, mode, fp),
   if ((flags = __sflags (ptr, mode, &oflags)) == 0)
     {
       _funlockfile (fp);
-#if !defined (__SINGLE_THREAD__) && defined (_POSIX_THREADS)
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
       pthread_setcancelstate (__oldcancel, &__oldcancel);
 #endif
       _fclose_r (ptr, fp);
-- 
1.7.7