Make pthread_atfork() track the DSO that called it like atexit() does,

unregistering callbacks if the DSO is unloaded.  Move the callback
handling from libpthread to libc, though libpthread still overrides the
inner call to handle locking and thread-library reinitialization.
Major version bump for both libc and libpthread.

verification that this fixes various ports ajacoutot@
asm assistance miod@; ok millert@ deraadt@

2 files changed, 30 insertions, 3 deletions

diff --git a/lib/libc/arch/i386/SYS.h b/lib/libc/arch/i386/SYS.h
index cc199d6bf3d..a6c1c852c03 100644
--- a/lib/libc/arch/i386/SYS.h
+++ b/lib/libc/arch/i386/SYS.h
@@ -29,7 +29,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$OpenBSD: SYS.h,v 1.19 2014/06/04 20:13:49 matthew Exp $
+ *	$OpenBSD: SYS.h,v 1.20 2015/04/07 01:27:06 guenther Exp $
  */
 
 #include <machine/asm.h>
@@ -49,6 +49,8 @@
 			ENTRY(_thread_sys_ ## x);	\
 			.weak _C_LABEL(x);		\
 			_C_LABEL(x) = _C_LABEL(_thread_sys_ ## x)
+#define	SYSENTRY_HIDDEN(x)				\
+			ENTRY(_thread_sys_ ## x)
 
 #define	__DO_SYSCALL(x)					\
 			movl $(SYS_ ## x),%eax;		\
@@ -62,6 +64,9 @@
 #define	_SYSCALL_NOERROR(x,y)				\
 		SYSENTRY(x);				\
 			__DO_SYSCALL(y);
+#define	_SYSCALL_HIDDEN_NOERROR(x,y)			\
+		SYSENTRY_HIDDEN(x);			\
+			__DO_SYSCALL(y);
 
 #define	SYSCALL_NOERROR(x)				\
 		_SYSCALL_NOERROR(x,x)
@@ -77,6 +82,15 @@
 			jmp *%ecx;			\
 		_SYSCALL_NOERROR(x,y)			\
 			jc 2b
+#define	_SYSCALL_HIDDEN(x,y)				\
+			.text;				\
+			.align 2;			\
+		2:	PIC_PROLOGUE;			\
+			movl PIC_GOT(CERROR), %ecx;	\
+			PIC_EPILOGUE;			\
+			jmp *%ecx;			\
+		_SYSCALL_HIDDEN_NOERROR(x,y)		\
+			jc 2b
 #else
 #define	_SYSCALL(x,y)					\
 			.text;				\
@@ -85,6 +99,13 @@
 			jmp PIC_PLT(CERROR);		\
 		_SYSCALL_NOERROR(x,y)			\
 			jc 2b
+#define	_SYSCALL_HIDDEN(x,y)				\
+			.text;				\
+			.align 2;			\
+		2:					\
+			jmp PIC_PLT(CERROR);		\
+		_SYSCALL_HIDDEN_NOERROR(x,y)		\
+			jc 2b
 #endif
 
 #define	SYSCALL(x)					\
@@ -99,9 +120,14 @@
 #define	PSEUDO(x,y)					\
 		_SYSCALL(x,y);				\
 			ret
+#define	PSEUDO_HIDDEN(x,y)				\
+		_SYSCALL_HIDDEN(x,y);			\
+			ret
 
 /* perform a syscall with the same name, set errno, return */
 #define	RSYSCALL(x)					\
 			PSEUDO(x,x);
+#define	RSYSCALL_HIDDEN(x)				\
+			PSEUDO_HIDDEN(x,x)
 
 	.globl	CERROR
diff --git a/lib/libc/arch/i386/sys/fork.S b/lib/libc/arch/i386/sys/fork.S
index 205ae5942c1..1e750d3f0d6 100644
--- a/lib/libc/arch/i386/sys/fork.S
+++ b/lib/libc/arch/i386/sys/fork.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fork.S,v 1.5 2015/03/31 04:32:01 guenther Exp $ */
+/*	$OpenBSD: fork.S,v 1.6 2015/04/07 01:27:06 guenther Exp $ */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -33,4 +33,5 @@
 
 #include "SYS.h"
 
-RSYSCALL(fork)
+RSYSCALL_HIDDEN(fork)
+WEAK_ALIAS(_thread_fork,_thread_sys_fork)