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, 14 insertions, 6 deletions

diff --git a/lib/libc/stdio/feof.c b/lib/libc/stdio/feof.c
index 3581100..60cad53 100644
--- a/lib/libc/stdio/feof.c
+++ b/lib/libc/stdio/feof.c
@@ -42,16 +42,24 @@ static const char rcsid[] =
   "$FreeBSD$";
 #endif /* LIBC_SCCS and not lint */
 
+#include "namespace.h"
 #include <stdio.h>
+#include "un-namespace.h"
+#include "libc_private.h"
 
 /*
- * A subroutine version of the macro feof.
+ * feof has traditionally been a macro in <stdio.h>.  That is no
+ * longer true because it needs to be thread-safe.
+ *
+ * #undef feof
  */
-#undef feof
-
 int
-feof(fp)
-	FILE *fp;
+feof(FILE *fp)
 {
-	return (__sfeof(fp));
+	int	ret;
+
+	FLOCKFILE(fp);
+	ret= __sfeof(fp);
+	FUNLOCKFILE(fp);
+	return (ret);
 }