Add framework for resolving (pun intended) libc namespace issues, using

wrapper .h files and asm labels to let internal calls resolve directly and
not be overridable or use the PLT.  Then, apply that framework to most of
the functions in stdio.h, string.h, err.h, and wchar.h.  Delete the
should-have-been-hidden-all-along _v?(err|warn)[cx]? symbols while here.

tests clean on i386, amd64, sparc64, powerpc, and mips64

naming feedback from kettenis@ and millert@
ok kettenis@

11 files changed, 55 insertions, 21 deletions

diff --git a/lib/libc/arch/arm/SYS.h b/lib/libc/arch/arm/SYS.h
index ce42349711a..df72e5c1b3c 100644
--- a/lib/libc/arch/arm/SYS.h
+++ b/lib/libc/arch/arm/SYS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: SYS.h,v 1.10 2015/08/26 01:54:09 guenther Exp $	*/
+/*	$OpenBSD: SYS.h,v 1.11 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: SYS.h,v 1.8 2003/08/07 16:42:02 agc Exp $	*/
 
 /*-
@@ -38,6 +38,30 @@
 #include <machine/asm.h>
 #include <sys/syscall.h>
 
+
+/*
+ * We define a hidden alias with the prefix "_libc_" for each global symbol
+ * that may be used internally.  By referencing _libc_x instead of x, other
+ * parts of libc prevent overriding by the application and avoid unnecessary
+ * relocations.
+ */
+#define _HIDDEN(x)		_libc_##x
+#define _HIDDEN_ALIAS(x,y)			\
+	STRONG_ALIAS(_HIDDEN(x),y);		\
+	.hidden _HIDDEN(x)
+#define _HIDDEN_FALIAS(x,y)			\
+	_HIDDEN_ALIAS(x,y);			\
+	.type _HIDDEN(x),@function
+
+/*
+ * For functions implemented in ASM that aren't syscalls.
+ *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
+ *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
+ */
+#define	END_STRONG(x)	END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x))
+#define	END_WEAK(x)	END_STRONG(x); .weak x
+
+
 #define SYSENTRY(x)					\
 	.weak _C_LABEL(x);				\
 	_C_LABEL(x) = _C_LABEL(_thread_sys_ ## x);	\
diff --git a/lib/libc/arch/arm/string/_memcpy.S b/lib/libc/arch/arm/string/_memcpy.S
index dee8de3e080..ef2ccc442b9 100644
--- a/lib/libc/arch/arm/string/_memcpy.S
+++ b/lib/libc/arch/arm/string/_memcpy.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: _memcpy.S,v 1.4 2015/06/08 14:22:05 jsg Exp $	*/
+/*	$OpenBSD: _memcpy.S,v 1.5 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: _memcpy.S,v 1.4 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*-
@@ -30,7 +30,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 /*
  * This is one fun bit of code ...
@@ -462,3 +462,4 @@ ENTRY(_memcpy)
 .Lmemcpy_bsrcul1l4:
 	add	r1, r1, #1
 	b	.Lmemcpy_bl4
+END(_memcpy)
diff --git a/lib/libc/arch/arm/string/bcopy.S b/lib/libc/arch/arm/string/bcopy.S
index 3953fef1732..f71b5ce7cbd 100644
--- a/lib/libc/arch/arm/string/bcopy.S
+++ b/lib/libc/arch/arm/string/bcopy.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bcopy.S,v 1.3 2008/06/26 05:42:04 ray Exp $	*/
+/*	$OpenBSD: bcopy.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: bcopy.S,v 1.2 2001/07/16 05:50:06 matt Exp $	*/
 
 /*-
@@ -30,7 +30,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 /* bcopy = memcpy/memmove with arguments reversed. */
 
@@ -40,3 +40,4 @@ ENTRY(bcopy)
 	eor     r1, r0, r1 
 	eor     r0, r1, r0 
 	b	PIC_SYM(_C_LABEL(_memcpy), PLT)
+END_WEAK(bcopy)
diff --git a/lib/libc/arch/arm/string/bzero.S b/lib/libc/arch/arm/string/bzero.S
index 40430a86873..419e2bbdc9d 100644
--- a/lib/libc/arch/arm/string/bzero.S
+++ b/lib/libc/arch/arm/string/bzero.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bzero.S,v 1.3 2008/06/26 05:42:04 ray Exp $	*/
+/*	$OpenBSD: bzero.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: bzero.S,v 1.2 2001/07/16 05:50:06 matt Exp $	*/
 
 /*-
@@ -30,9 +30,10 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 ENTRY(bzero)
 	mov	r2, r1
 	mov	r1, #0
 	b	PIC_SYM(_C_LABEL(memset), PLT)
+END_WEAK(bzero)
diff --git a/lib/libc/arch/arm/string/ffs.S b/lib/libc/arch/arm/string/ffs.S
index 9dd7e5aef2f..7f4b289d860 100644
--- a/lib/libc/arch/arm/string/ffs.S
+++ b/lib/libc/arch/arm/string/ffs.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ffs.S,v 1.3 2009/10/28 06:49:54 deraadt Exp $	*/
+/*	$OpenBSD: ffs.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: ffs.S,v 1.5 2003/04/05 23:08:52 bjh21 Exp $	*/
 /*
  * Copyright (c) 2001 Christopher Gilbert
@@ -29,7 +29,7 @@
  * SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 /*
  * ffs - find first set bit, this algorithm isolates the first set
@@ -61,6 +61,7 @@ ENTRY(ffs)
 	ldrneb  r0, [ r2, r0, lsr #26 ]
 
         mov   pc, lr
+END_WEAK(ffs)
 .text;
 .type .L_ffs_table, _ASM_TYPE_OBJECT;
 .L_ffs_table:
diff --git a/lib/libc/arch/arm/string/memcmp.S b/lib/libc/arch/arm/string/memcmp.S
index 3a564c7338a..f7c5c966663 100644
--- a/lib/libc/arch/arm/string/memcmp.S
+++ b/lib/libc/arch/arm/string/memcmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memcmp.S,v 1.4 2009/10/28 06:49:54 deraadt Exp $	*/
+/*	$OpenBSD: memcmp.S,v 1.5 2015/08/31 02:53:56 guenther Exp $	*/
 /*      $NetBSD: memcmp.S,v 1.2 2003/04/05 23:08:52 bjh21 Exp $ */
 
 /*
@@ -29,7 +29,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 ENTRY(memcmp)
 /* if (len == 0) return 0 */
@@ -50,3 +50,4 @@ ENTRY(memcmp)
 	beq	1b
 	sub	r0, r2, r3
 	mov	pc, lr
+END_STRONG(memcmp)
diff --git a/lib/libc/arch/arm/string/memcpy.S b/lib/libc/arch/arm/string/memcpy.S
index 6aeb5b84bac..5797c6d6f33 100644
--- a/lib/libc/arch/arm/string/memcpy.S
+++ b/lib/libc/arch/arm/string/memcpy.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memcpy.S,v 1.4 2014/11/30 19:43:56 deraadt Exp $	*/
+/*	$OpenBSD: memcpy.S,v 1.5 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: memcpy.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*-
@@ -30,7 +30,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 /*
  * XXX
@@ -42,3 +42,4 @@ ENTRY(memcpy)
 	stmfd	sp!, {r0, lr}
 	bl	PIC_SYM(_C_LABEL(_memcpy), PLT)
 	ldmfd	sp!, {r0, pc}
+END_STRONG(memcpy)
diff --git a/lib/libc/arch/arm/string/memmove.S b/lib/libc/arch/arm/string/memmove.S
index 8244afb7de1..c2f107e3cd8 100644
--- a/lib/libc/arch/arm/string/memmove.S
+++ b/lib/libc/arch/arm/string/memmove.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memmove.S,v 1.3 2008/06/26 05:42:04 ray Exp $	*/
+/*	$OpenBSD: memmove.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: memmove.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*-
@@ -30,9 +30,10 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 ENTRY(memmove)
 	stmfd	sp!, {r0, lr}
 	bl	PIC_SYM(_C_LABEL(_memcpy), PLT)
 	ldmfd	sp!, {r0, pc}
+END_STRONG(memmove)
diff --git a/lib/libc/arch/arm/string/memset.S b/lib/libc/arch/arm/string/memset.S
index a4c3d158938..5ab2f9f3bcd 100644
--- a/lib/libc/arch/arm/string/memset.S
+++ b/lib/libc/arch/arm/string/memset.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memset.S,v 1.3 2015/06/08 14:22:05 jsg Exp $	*/
+/*	$OpenBSD: memset.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*	$NetBSD: memset.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*
@@ -33,7 +33,7 @@
  * SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 /*
  * Sets a block of memory to the specified value
@@ -127,3 +127,4 @@ ENTRY(memset)
 
 	ldmfd	sp!, {r0}
 	mov	pc, lr			/* Exit */
+END_STRONG(memset)
diff --git a/lib/libc/arch/arm/string/strcmp.S b/lib/libc/arch/arm/string/strcmp.S
index ea6078e7f9c..223610d0925 100644
--- a/lib/libc/arch/arm/string/strcmp.S
+++ b/lib/libc/arch/arm/string/strcmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strcmp.S,v 1.3 2005/08/07 16:40:14 espie Exp $	*/
+/*	$OpenBSD: strcmp.S,v 1.4 2015/08/31 02:53:56 guenther Exp $	*/
 /*      $NetBSD: strcmp.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $ */
 
 /*
@@ -29,7 +29,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 ENTRY(strcmp)
 1:
@@ -40,3 +40,4 @@ ENTRY(strcmp)
 	beq	1b
 	sub	r0, r2, r3
 	mov	pc, lr
+END_STRONG(strcmp)
diff --git a/lib/libc/arch/arm/string/strncmp.S b/lib/libc/arch/arm/string/strncmp.S
index f8960bbc84b..1014d5dc4ea 100644
--- a/lib/libc/arch/arm/string/strncmp.S
+++ b/lib/libc/arch/arm/string/strncmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strncmp.S,v 1.4 2009/05/03 05:09:40 drahn Exp $	*/
+/*	$OpenBSD: strncmp.S,v 1.5 2015/08/31 02:53:56 guenther Exp $	*/
 /*      $NetBSD: strncmp.S,v 1.2 2003/04/05 23:08:52 bjh21 Exp $ */
 
 /*
@@ -29,7 +29,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
+#include "SYS.h"
 
 ENTRY(strncmp)
 /* if (len == 0) return 0 */
@@ -51,3 +51,4 @@ ENTRY(strncmp)
 	beq	1b
 	sub	r0, r2, r3
 	mov	pc, lr
+END_STRONG(strncmp)