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, 7 insertions, 4 deletions

diff --git a/lib/libc/stdio/ftell.c b/lib/libc/stdio/ftell.c
index b7d449e187d..9d4d54628ac 100644
--- a/lib/libc/stdio/ftell.c
+++ b/lib/libc/stdio/ftell.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ftell.c,v 1.6 2005/08/08 08:05:36 espie Exp $ */
+/*	$OpenBSD: ftell.c,v 1.7 2009/10/21 16:04:23 guenther Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -45,20 +45,22 @@ ftello(FILE *fp)
 
 	if (fp->_seek == NULL) {
 		errno = ESPIPE;			/* historic practice */
-		return ((off_t)-1);
+		pos = -1;
+		goto out;
 	}
 
 	/*
 	 * Find offset of underlying I/O object, then
 	 * adjust for buffered bytes.
 	 */
+	FLOCKFILE(fp);
 	__sflush(fp);		/* may adjust seek offset on append stream */
 	if (fp->_flags & __SOFF)
 		pos = fp->_offset;
 	else {
 		pos = (*fp->_seek)(fp->_cookie, (fpos_t)0, SEEK_CUR);
-		if (pos == -1L)
-			return (pos);
+		if (pos == -1)
+			goto out;
 	}
 	if (fp->_flags & __SRD) {
 		/*
@@ -77,6 +79,7 @@ ftello(FILE *fp)
 		 */
 		pos += fp->_p - fp->_bf._base;
 	}
+out:	FUNLOCKFILE(fp);
 	return (pos);
 }