libc MT-safety, part 2.

Add a lock to FILE.  flockfile and friends are now implemented
(for the most part) in libc.  flockfile_debug is implemented in
libc_r; I suppose it's about time to kill it but will do it in
a future commit.

Fix a potential deadlock in _fwalk in a threaded environment.
A file flag (__SIGN) was added to stdio.h that, when set, tells
_fwalk to ignore it in its walk.  This seemed to be needed in
refill.c because each file needs to be locked when flushing.

Add a stub for pthread_self in libc.  This is needed by flockfile
which is allowed by POSIX to be recursive.

Make fgetpos() error return value (-1) match man page.

Remove recursive calls to locked functions (stdio); I think I've
got them all, but I may have missed a couple.

A few K&R -> ANSI conversions along with removal of a few instances
of "register".

$Id$ -> $FreeBSD$ in libc/stdio/rget.c

Not objected to:	-arch, a few months ago

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/libc/stdio/findfp.c b/lib/libc/stdio/findfp.c
index 30e8f90..f307e3e 100644
--- a/lib/libc/stdio/findfp.c
+++ b/lib/libc/stdio/findfp.c
@@ -82,7 +82,7 @@ static spinlock_t thread_lock = _SPINLOCK_INITIALIZER;
 #define THREAD_UNLOCK()	if (__isthreaded) _SPINUNLOCK(&thread_lock)
 
 #if NOT_YET
-#define	SET_GLUE_PTR(ptr, val)	atomic_set_ptr(&(ptr), (uintptr_t)(val))
+#define	SET_GLUE_PTR(ptr, val)	atomic_set_rel_ptr(&(ptr), (uintptr_t)(val))
 #else
 #define	SET_GLUE_PTR(ptr, val)	ptr = val
 #endif
@@ -150,7 +150,7 @@ found:
 	fp->_ub._size = 0;
 	fp->_lb._base = NULL;	/* no line buffer */
 	fp->_lb._size = 0;
-	/* fp->_lock = NULL; */
+/*	fp->_lock = NULL; */	/* once set always set (reused) */
 	return (fp);
 }
 
@@ -203,7 +203,7 @@ _cleanup()
 void
 __sinit()
 {
-	/* make sure we clean up on exit */
+	/* Make sure we clean up on exit. */
 	__cleanup = _cleanup;		/* conservative */
 	__sdidinit = 1;
 }