Fix the handle locking in stdio to use flockfile/funlockfile

internally when and where required.  Macros in <stdio.h> are updated
to automatically call the underlying functions when the process is
threaded to obtain the necessary locking.  A private mutex is added
to protect __sglue, the internal list of FILE handles, and another
to protect the one-time initialization.  Some routines in libc that
use getc() change to use getc_unlocked() as they're either protected
by their own lock or aren't thread-safe routines anyway.

ok kurt@, earlier version tested by sthen@ and jj@

1 files changed, 8 insertions, 2 deletions

diff --git a/lib/libc/stdio/ferror.c b/lib/libc/stdio/ferror.c
index 0d2cf01a1bc..29b08d3642a 100644
--- a/lib/libc/stdio/ferror.c
+++ b/lib/libc/stdio/ferror.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ferror.c,v 1.5 2005/08/08 08:05:36 espie Exp $ */
+/*	$OpenBSD: ferror.c,v 1.6 2009/10/21 16:04:23 guenther Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -32,6 +32,7 @@
  */
 
 #include <stdio.h>
+#include "local.h"
 
 /*
  * A subroutine version of the macro ferror.
@@ -41,5 +42,10 @@
 int
 ferror(FILE *fp)
 {
-	return (__sferror(fp));
+	int     ret;
+
+	FLOCKFILE(fp);
+	ret = __sferror(fp);
+	FUNLOCKFILE(fp);
+	return (ret);
 }