Use a Thread Information Block in both single and multi-threaded programs.

This stores errno, the cancelation flags, and related bits for each thread
and is allocated by ld.so or libc.a.  This is an ABI break from 5.9-stable!

Make libpthread dlopen'able by moving the cancelation wrappers into libc
and doing locking and fork/errno handling via callbacks that libpthread
registers when it first initializes.  'errno' *must* be declared via
<errno.h> now!

Clean up libpthread's symbol exports like libc.

On powerpc, offset the TIB/TCB/TLS data from the register per the ELF spec.

Testing by various, particularly sthen@ and patrick@
ok kettenis@

2 files changed, 24 insertions, 27 deletions

diff --git a/lib/libc/stdio/flockfile.c b/lib/libc/stdio/flockfile.c
index 5ffcae57609..88d90b8e4b1 100644
--- a/lib/libc/stdio/flockfile.c
+++ b/lib/libc/stdio/flockfile.c
@@ -1,41 +1,29 @@
-/*	$OpenBSD: flockfile.c,v 1.8 2012/09/01 01:08:16 fgsch Exp $	*/
+/*	$OpenBSD: flockfile.c,v 1.9 2016/05/07 19:05:22 guenther Exp $	*/
 
-#include <sys/time.h>
 #include <stdio.h>
-#include "thread_private.h"
-
-/*
- * Subroutine versions of the macros in <stdio.h>
- * Note that these are all no-ops because libc does not do threads.
- * Strong implementation of file locking in librthread/rthread_file.c
- */
-
-#undef flockfile
-#undef ftrylockfile
-#undef funlockfile
-
-WEAK_PROTOTYPE(flockfile);
-WEAK_PROTOTYPE(ftrylockfile);
-WEAK_PROTOTYPE(funlockfile);
-
-WEAK_ALIAS(flockfile);
-WEAK_ALIAS(ftrylockfile);
-WEAK_ALIAS(funlockfile);
+#include "local.h"
 
 void
-WEAK_NAME(flockfile)(FILE * fp)
+flockfile(FILE *fp)
 {
+	FLOCKFILE(fp);
 }
+DEF_WEAK(flockfile);
 
 
 int
-WEAK_NAME(ftrylockfile)(FILE *fp)
+ftrylockfile(FILE *fp)
 {
+	if (_thread_cb.tc_ftrylockfile != NULL)
+		return (_thread_cb.tc_ftrylockfile(fp));
 
 	return 0;
 }
+DEF_WEAK(ftrylockfile);
 
 void
-WEAK_NAME(funlockfile)(FILE * fp)
+funlockfile(FILE *fp)
 {
+	FUNLOCKFILE(fp);
 }
+DEF_WEAK(funlockfile);
diff --git a/lib/libc/stdio/local.h b/lib/libc/stdio/local.h
index 94b2804ff18..ad888b0fd50 100644
--- a/lib/libc/stdio/local.h
+++ b/lib/libc/stdio/local.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: local.h,v 1.23 2015/10/25 18:01:24 guenther Exp $	*/
+/*	$OpenBSD: local.h,v 1.24 2016/05/07 19:05:22 guenther Exp $	*/
 
 /*-
  * Copyright (c) 1990, 1993
@@ -40,6 +40,7 @@
 #include <wchar.h> 
 #include "wcio.h"
 #include "fileext.h"
+#include "thread_private.h"
 
 void	_cleanup(void);
 int	_fwalk(int (*)(FILE *));
@@ -96,5 +97,13 @@ __END_HIDDEN_DECLS
 	(fp)->_lb._base = NULL; \
 }
 
-#define FLOCKFILE(fp)	do { if (__isthreaded) flockfile(fp); } while (0)
-#define FUNLOCKFILE(fp)	do { if (__isthreaded) funlockfile(fp); } while (0)
+#define FLOCKFILE(fp)							\
+	do {								\
+		if (_thread_cb.tc_flockfile != NULL)			\
+			_thread_cb.tc_flockfile(fp);			\
+	} while (0)
+#define FUNLOCKFILE(fp)							\
+	do {								\
+		if (_thread_cb.tc_funlockfile != NULL)			\
+			_thread_cb.tc_funlockfile(fp);			\
+	} while (0)