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, 8 insertions, 11 deletions

diff --git a/lib/libc/stdio/fgetpos.c b/lib/libc/stdio/fgetpos.c
index 239f6d1..51f14ef 100644
--- a/lib/libc/stdio/fgetpos.c
+++ b/lib/libc/stdio/fgetpos.c
@@ -42,19 +42,16 @@ 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"
 
 int
-fgetpos(fp, pos)
-	FILE *fp;
-	fpos_t *pos;
+fgetpos(FILE *fp, fpos_t *pos)
 {
-	int retval;
-	FLOCKFILE(fp);
-	retval = (*pos = ftello(fp)) == (fpos_t)-1;
-	FUNLOCKFILE(fp);
-	return(retval);
+	/*
+	 * ftello is thread-safe; no need to lock fp.
+	 */
+	if ((*pos = ftello(fp)) == (fpos_t)-1)
+		return (-1);
+	else
+		return (0);
 }