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@

1 files changed, 4 insertions, 2 deletions

diff --git a/src/lib/libc/include/namespace.h b/src/lib/libc/include/namespace.h
index 16d524f666..980c1a8dd6 100644
--- a/src/lib/libc/include/namespace.h
+++ b/src/lib/libc/include/namespace.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: namespace.h,v 1.9 2016/04/05 04:28:32 guenther Exp $  */
+/*      $OpenBSD: namespace.h,v 1.10 2016/05/07 19:05:22 guenther Exp $ */
 
 #ifndef _LIBC_NAMESPACE_H_
 #define _LIBC_NAMESPACE_H_
@@ -139,12 +139,14 @@
 #define CANCEL(x)               _libc_##x##_cancel
 #define WRAP(x)                 _libc_##x##_wrap
 #define HIDDEN_STRING(x)        "_libc_" __STRING(x)
+#define CANCEL_STRING(x)        "_libc_" __STRING(x) "_cancel"
 #define WRAP_STRING(x)          "_libc_" __STRING(x) "_wrap"
 
 #define PROTO_NORMAL(x)         __dso_hidden typeof(x) x asm(HIDDEN_STRING(x))
 #define PROTO_STD_DEPRECATED(x) typeof(x) x __attribute__((deprecated))
 #define PROTO_DEPRECATED(x)     typeof(x) x __attribute__((deprecated, weak))
-#define PROTO_CANCEL(x)         PROTO_NORMAL(x), CANCEL(x)
+#define PROTO_CANCEL(x)         __dso_hidden typeof(x) HIDDEN(x), \
+                                        x asm(CANCEL_STRING(x))
 #define PROTO_WRAP(x)           PROTO_NORMAL(x), WRAP(x)
 
 #define DEF_STRONG(x)           __strong_alias(x, HIDDEN(x))