Eliminate userspace caching by getlogin_r/setlogin; make the getlogin

syscall behave exactly like userspace getlogin_r() and rename it to
match.  Eliminate the reduced-to-no-op wrappers of the syscalls.
Eliminate the unnecessary per-thread static buffering by getlogin().

ok kettenis@ deraadt@

4 files changed, 20 insertions, 65 deletions

diff --git a/lib/libc/Symbols.list b/lib/libc/Symbols.list
index f954403d882..5513d8a0268 100644
--- a/lib/libc/Symbols.list
+++ b/lib/libc/Symbols.list
@@ -46,9 +46,7 @@ _thread_sys___thrsigdivert
 _thread_sys___thrsleep
 _thread_sys___thrwakeup
 _thread_sys__exit
-_thread_sys__getlogin
 _thread_sys__ptrace
-_thread_sys__setlogin
 _thread_sys_accept4
 _thread_sys_accept
 _thread_sys_access
@@ -103,6 +101,7 @@ _thread_sys_getfsstat
 _thread_sys_getgid
 _thread_sys_getgroups
 _thread_sys_getitimer
+_thread_sys_getlogin_r
 _thread_sys_getpeername
 _thread_sys_getpgid
 _thread_sys_getpgrp
@@ -195,6 +194,7 @@ _thread_sys_seteuid
 _thread_sys_setgid
 _thread_sys_setgroups
 _thread_sys_setitimer
+_thread_sys_setlogin
 _thread_sys_setpgid
 _thread_sys_setpriority
 _thread_sys_setregid
diff --git a/lib/libc/gen/getlogin.c b/lib/libc/gen/getlogin.c
index ff2837ae99d..c6072f1f86f 100644
--- a/lib/libc/gen/getlogin.c
+++ b/lib/libc/gen/getlogin.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: getlogin.c,v 1.13 2015/09/12 14:56:50 guenther Exp $ */
+/*	$OpenBSD: getlogin.c,v 1.14 2016/03/30 07:52:47 guenther Exp $ */
 /*
  * Copyright (c) 1988, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -30,70 +30,25 @@
 
 #include <errno.h>
 #include <limits.h>
-#include <pwd.h>
-#include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <utmp.h>
 
 #include "thread_private.h"
 
-_THREAD_PRIVATE_MUTEX(logname);
-static int  logname_valid = 0;
-static char logname[LOGIN_NAME_MAX + 1];
-
-int	_getlogin(char *, size_t);
-int	_setlogin(const char *);
+static char logname[LOGIN_NAME_MAX];
 
 char *
 getlogin(void)
 {
-	_THREAD_PRIVATE_KEY(getlogin);
-	char * name = (char *)_THREAD_PRIVATE(getlogin, logname, NULL);
+	int err;
 
-	if ((errno = getlogin_r(name, sizeof logname)) != 0)
+	if ((err = getlogin_r(logname, sizeof logname)) != 0) {
+		errno = err;
 		return NULL;
-	if (*name == '\0') {
+	}
+	if (*logname == '\0') {
 		errno = ENOENT;  /* well? */
 		return NULL;
 	}
-	return name;
-}
-
-int
-getlogin_r(char *name, size_t namelen)
-{
-	int logname_size;
-
-	_THREAD_PRIVATE_MUTEX_LOCK(logname);
-	if (!logname_valid) {
-		if (_getlogin(logname, sizeof(logname) - 1) < 0) {
-			_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
-			return errno;
-		}
-		logname_valid = 1;
-		logname[LOGIN_NAME_MAX] = '\0';	/* paranoia */
-	}
-	logname_size = strlen(logname) + 1;
-	if (namelen < logname_size) {
-		_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
-		return ERANGE;
-	}
-	memcpy(name, logname, logname_size);
-	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
-	return 0;
-}
-DEF_WEAK(getlogin_r);
-
-int
-setlogin(const char *name)
-{
-	int ret;
-
-	_THREAD_PRIVATE_MUTEX_LOCK(logname);
-	ret = _setlogin(name);
-	if (ret == 0)
-		logname_valid = 0;
-	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
-	return ret;
+	return logname;
 }
diff --git a/lib/libc/hidden/unistd.h b/lib/libc/hidden/unistd.h
index 835dc295b8c..3565869772a 100644
--- a/lib/libc/hidden/unistd.h
+++ b/lib/libc/hidden/unistd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: unistd.h,v 1.6 2016/03/20 02:32:40 guenther Exp $	*/
+/*	$OpenBSD: unistd.h,v 1.7 2016/03/30 07:52:47 guenther Exp $	*/
 /*
  * Copyright (c) 2015 Philip Guenther <guenther@openbsd.org>
  *
@@ -73,7 +73,7 @@ PROTO_NORMAL(getgrouplist);
 PROTO_NORMAL(getgroups);
 PROTO_DEPRECATED(gethostid);
 PROTO_NORMAL(gethostname);
-/*PROTO_BARE(getlogin);*/
+PROTO_DEPRECATED(getlogin);
 PROTO_NORMAL(getlogin_r);
 PROTO_DEPRECATED(getmode);
 PROTO_DEPRECATED(getopt);
@@ -136,7 +136,7 @@ PROTO_NORMAL(setgid);
 PROTO_NORMAL(setgroups);
 PROTO_DEPRECATED(sethostid);
 PROTO_DEPRECATED(sethostname);
-/*PROTO_WRAP(setlogin);*/
+PROTO_NORMAL(setlogin);
 PROTO_DEPRECATED(setmode);
 PROTO_NORMAL(setpgid);
 PROTO_DEPRECATED(setpgrp);
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index b7feb186eb0..33d762524f9 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.139 2016/03/30 06:38:42 jmc Exp $
+#	$OpenBSD: Makefile.inc,v 1.140 2016/03/30 07:52:47 guenther Exp $
 #	$NetBSD: Makefile.inc,v 1.35 1995/10/16 23:49:07 jtc Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/17/93
 
@@ -52,7 +52,7 @@ ASM=	__get_tcb.o __getcwd.o __semctl.o __set_tcb.o __syscall.o \
 	recvfrom.o recvmsg.o rename.o renameat.o revoke.o rmdir.o \
 	sched_yield.o select.o semget.o semop.o sendmsg.o sendsyslog.o \
 	sendto.o \
-	setegid.o seteuid.o setgid.o setgroups.o setitimer.o \
+	setegid.o seteuid.o setgid.o setgroups.o setitimer.o setlogin.o \
 	setpgid.o setpriority.o setregid.o setresgid.o setresuid.o \
 	setreuid.o setrlimit.o setrtable.o setsid.o setsockopt.o \
 	settimeofday.o setuid.o shmat.o shmctl.o shmdt.o \
@@ -71,13 +71,13 @@ PASM=	${ASM:.o=.po}
 SASM=	${ASM:.o=.so}
 DASM=	${ASM:.o=.do}
 
-PSEUDO=	_getlogin.o _setlogin.o _ptrace.o
+PSEUDO=	_ptrace.o
 GPSEUDO=${PSEUDO:.o=.go}
 PPSEUDO=${PSEUDO:.o=.po}
 SPSEUDO=${PSEUDO:.o=.so}
 DPSEUDO=${PSEUDO:.o=.do}
 
-PSEUDO_NOERR=	_exit.o
+PSEUDO_NOERR=	_exit.o getlogin_r.o
 GPSEUDO_NOERR=${PSEUDO_NOERR:.o=.go}
 PPSEUDO_NOERR=${PSEUDO_NOERR:.o=.po}
 SPSEUDO_NOERR=${PSEUDO_NOERR:.o=.so}
@@ -104,13 +104,13 @@ GENERATE.rsyscall=\
 	printf '\#include "SYS.h"\nRSYSCALL(${.PREFIX})\n'
 GENERATE.pseudo=\
 	echo creating ${.TARGET} && \
-	printf '\#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/_//})\n'
+	printf '\#include "SYS.h"\nPSEUDO(${.PREFIX},${.PREFIX:S/^_//})\n'
 GENERATE.pseudo_noerr=\
 	echo creating ${.TARGET} && \
-	printf '\#include "SYS.h"\nPSEUDO_NOERROR(${.PREFIX},${.PREFIX:S/_//})\n'
+	printf '\#include "SYS.h"\nPSEUDO_NOERROR(${.PREFIX},${.PREFIX:S/^_//})\n'
 GENERATE.rsyscall_hidden=\
 	echo creating ${.TARGET} && \
-	printf '\#include "SYS.h"\nRSYSCALL_HIDDEN(${.PREFIX:S/_//})\n'
+	printf '\#include "SYS.h"\nRSYSCALL_HIDDEN(${.PREFIX:S/^_//})\n'
 
 # ...and one of these to control how it's compiled
 FINISH=	${COMPILE.S} ${CFLAGS:M-[ID]*} ${AINC} -x assembler-with-cpp -