Remove _THREAD_SAFE and make libc thread-safe by default by

adding (weak definitions to) stubs for some of the pthread
functions.  If the threads library is linked in, the real
pthread functions will pulled in.

Use the following convention for system calls wrapped by the
threads library:
	__sys_foo - actual system call
	_foo - weak definition to __sys_foo
	foo - weak definition to __sys_foo

Change all libc uses of system calls wrapped by the threads
library from foo to _foo.  In order to define the prototypes
for _foo(), we introduce namespace.h and un-namespace.h
(suggested by bde).  All files that need to reference these
system calls, should include namespace.h before any standard
includes, then include un-namespace.h after the standard
includes and before any local includes.  <db.h> is an exception
and shouldn't be included in between namespace.h and
un-namespace.h  namespace.h will define foo to _foo, and
un-namespace.h will undefine foo.

Try to eliminate some of the recursive calls to MT-safe
functions in libc/stdio in preparation for adding a mutex
to FILE.  We have recursive mutexes, but would like to avoid
using them if possible.

Remove uneeded includes of <errno.h> from a few files.

Add $FreeBSD$ to a few files in order to pass commitprep.

Approved by:	-arch

6 files changed, 100 insertions, 123 deletions

diff --git a/lib/libc/stdtime/asctime.c b/lib/libc/stdtime/asctime.c
index 832f185..d6e02b8 100644
--- a/lib/libc/stdtime/asctime.c
+++ b/lib/libc/stdtime/asctime.c
@@ -1,6 +1,8 @@
 /*
 ** This file is in the public domain, so clarified as of
 ** June 5, 1996 by Arthur David Olson (arthur_david_olson@nih.gov).
+*
+* $FreeBSD$
 */
 
 #ifndef lint
@@ -11,7 +13,9 @@ static char	elsieid[] = "@(#)asctime.c	7.7";
 
 /*LINTLIBRARY*/
 
+#include "namespace.h"
 #include "private.h"
+#include "un-namespace.h"
 #include "tzfile.h"
 
 /*
diff --git a/lib/libc/stdtime/difftime.c b/lib/libc/stdtime/difftime.c
index f178524..64a5ea2 100644
--- a/lib/libc/stdtime/difftime.c
+++ b/lib/libc/stdtime/difftime.c
@@ -1,6 +1,8 @@
 /*
 ** This file is in the public domain, so clarified as of
 ** June 5, 1996 by Arthur David Olson (arthur_david_olson@nih.gov).
+*
+* $FreeBSD$
 */
 
 #ifndef lint
@@ -11,7 +13,9 @@ static char	elsieid[] = "@(#)difftime.c	7.7";
 
 /*LINTLIBRARY*/
 
+#include "namespace.h"
 #include "private.h"
+#include "un-namespace.h"
 
 /*
 ** Algorithm courtesy Paul Eggert (eggert@twinsun.com).
diff --git a/lib/libc/stdtime/localtime.c b/lib/libc/stdtime/localtime.c
index 84a4ca9..e336414 100644
--- a/lib/libc/stdtime/localtime.c
+++ b/lib/libc/stdtime/localtime.c
@@ -19,16 +19,20 @@ static char	elsieid[] = "@(#)localtime.c	7.57";
 
 /*LINTLIBRARY*/
 
+#include "namespace.h"
 #include <sys/types.h>
 #include <sys/stat.h>
-
+#include <fcntl.h>
+#include <pthread.h>
 #include "private.h"
+#include "un-namespace.h"
+
 #include "tzfile.h"
-#include "fcntl.h"
-#ifdef	_THREAD_SAFE
-#include <pthread.h>
-#include "pthread_private.h"
-#endif
+
+#include "libc_private.h"
+
+#define	_MUTEX_LOCK(x)		if (__isthreaded) _pthread_mutex_lock(x)
+#define	_MUTEX_UNLOCK(x)	if (__isthreaded) _pthread_mutex_unlock(x)
 
 /*
 ** SunOS 4.1.1 headers lack O_BINARY.
@@ -172,12 +176,8 @@ static struct state	gmtmem;
 static char		lcl_TZname[TZ_STRLEN_MAX + 1];
 static int		lcl_is_set;
 static int		gmt_is_set;
-#ifdef	_THREAD_SAFE
-static struct pthread_mutex	_lcl_mutexd = PTHREAD_MUTEX_STATIC_INITIALIZER;
-static struct pthread_mutex	_gmt_mutexd = PTHREAD_MUTEX_STATIC_INITIALIZER;
-static pthread_mutex_t		lcl_mutex   = &_lcl_mutexd;
-static pthread_mutex_t		gmt_mutex   = &_gmt_mutexd;
-#endif
+static pthread_mutex_t	lcl_mutex = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t	gmt_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 char *			tzname[2] = {
 	wildabbr,
@@ -316,7 +316,7 @@ register struct state * const	sp;
 		     	return -1;
 		if ((fid = _open(name, OPEN_MODE)) == -1)
 			return -1;
-		if ((fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode))
+		if ((_fstat(fid, &stab) < 0) || !S_ISREG(stab.st_mode))
 			return -1;
 	}
 	{
@@ -929,20 +929,8 @@ struct state * const	sp;
 		(void) tzparse(gmt, sp, TRUE);
 }
 
-#ifndef STD_INSPIRED
-/*
-** A non-static declaration of tzsetwall in a system header file
-** may cause a warning about this upcoming static declaration...
-*/
-static
-#endif /* !defined STD_INSPIRED */
-#ifdef	_THREAD_SAFE
-void
-tzsetwall_basic P((void))
-#else
-void
-tzsetwall P((void))
-#endif
+static void
+tzsetwall_basic(void)
 {
 	if (lcl_is_set < 0)
 		return;
@@ -962,23 +950,16 @@ tzsetwall P((void))
 	settzname();
 }
 
-#ifdef	_THREAD_SAFE
 void
 tzsetwall P((void))
 {
-	pthread_mutex_lock(&lcl_mutex);
+	_MUTEX_LOCK(&lcl_mutex);
 	tzsetwall_basic();
-	pthread_mutex_unlock(&lcl_mutex);
+	_MUTEX_UNLOCK(&lcl_mutex);
 }
-#endif
 
-#ifdef	_THREAD_SAFE
 static void
-tzset_basic P((void))
-#else
-void
-tzset P((void))
-#endif
+tzset_basic(void)
 {
 	register const char *	name;
 
@@ -1018,15 +999,13 @@ tzset P((void))
 	settzname();
 }
 
-#ifdef	_THREAD_SAFE
 void
 tzset P((void))
 {
-	pthread_mutex_lock(&lcl_mutex);
+	_MUTEX_LOCK(&lcl_mutex);
 	tzset_basic();
-	pthread_mutex_unlock(&lcl_mutex);
+	_MUTEX_UNLOCK(&lcl_mutex);
 }
-#endif
 
 /*
 ** The easy way to behave "as if no library function calls" localtime
@@ -1089,14 +1068,10 @@ localtime_r(timep, p_tm)
 const time_t * const	timep;
 struct tm *p_tm;
 {
-#ifdef _THREAD_SAFE
-	pthread_mutex_lock(&lcl_mutex);
-#endif
+	_MUTEX_LOCK(&lcl_mutex);
 	tzset();
 	localsub(timep, 0L, p_tm);
-#ifdef _THREAD_SAFE
-	pthread_mutex_unlock(&lcl_mutex);
-#endif
+	_MUTEX_UNLOCK(&lcl_mutex);
 	return(p_tm);
 }
 
@@ -1104,36 +1079,36 @@ struct tm *
 localtime(timep)
 const time_t * const	timep;
 {
-#ifdef	_THREAD_SAFE
-	static struct pthread_mutex _localtime_mutex = PTHREAD_MUTEX_STATIC_INITIALIZER;
-	static pthread_mutex_t localtime_mutex = &_localtime_mutex;
+	static pthread_mutex_t localtime_mutex = PTHREAD_MUTEX_INITIALIZER;
 	static pthread_key_t localtime_key = -1;
 	struct tm *p_tm;
 
-	pthread_mutex_lock(&localtime_mutex);
-	if (localtime_key < 0) {
-		if (pthread_key_create(&localtime_key, free) < 0) {
-			pthread_mutex_unlock(&localtime_mutex);
-			return(NULL);
+	if (__isthreaded != 0) {
+		_pthread_mutex_lock(&localtime_mutex);
+		if (localtime_key < 0) {
+			if (_pthread_key_create(&localtime_key, free) < 0) {
+				_pthread_mutex_unlock(&localtime_mutex);
+				return(NULL);
+			}
 		}
+		_pthread_mutex_unlock(&localtime_mutex);
+		p_tm = _pthread_getspecific(localtime_key);
+		if (p_tm == NULL) {
+			if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
+			    == NULL)
+				return(NULL);
+			_pthread_setspecific(localtime_key, p_tm);
+		}
+		_pthread_mutex_lock(&lcl_mutex);
+		tzset();
+		localsub(timep, 0L, p_tm);
+		_pthread_mutex_unlock(&lcl_mutex);
+		return(p_tm);
+	} else {
+		tzset();
+		localsub(timep, 0L, &tm);
+		return(&tm);
 	}
-	pthread_mutex_unlock(&localtime_mutex);
-	p_tm = pthread_getspecific(localtime_key);
-	if (p_tm == NULL) {
-		if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) == NULL)
-			return(NULL);
-		pthread_setspecific(localtime_key, p_tm);
-	}
-	pthread_mutex_lock(&lcl_mutex);
-	tzset();
-	localsub(timep, 0L, p_tm);
-	pthread_mutex_unlock(&lcl_mutex);
-	return p_tm;
-#else
-	tzset();
-	localsub(timep, 0L, &tm);
-	return &tm;
-#endif
 }
 
 /*
@@ -1146,9 +1121,7 @@ const time_t * const	timep;
 const long		offset;
 struct tm * const	tmp;
 {
-#ifdef	_THREAD_SAFE
-	pthread_mutex_lock(&gmt_mutex);
-#endif
+	_MUTEX_LOCK(&gmt_mutex);
 	if (!gmt_is_set) {
 		gmt_is_set = TRUE;
 #ifdef ALL_STATE
@@ -1157,9 +1130,7 @@ struct tm * const	tmp;
 #endif /* defined ALL_STATE */
 			gmtload(gmtptr);
 	}
-#ifdef	_THREAD_SAFE
-	pthread_mutex_unlock(&gmt_mutex);
-#endif
+	_MUTEX_UNLOCK(&gmt_mutex);
 	timesub(timep, offset, gmtptr, tmp);
 #ifdef TM_ZONE
 	/*
@@ -1186,36 +1157,37 @@ struct tm *
 gmtime(timep)
 const time_t * const	timep;
 {
-#ifdef	_THREAD_SAFE
-	static struct pthread_mutex _gmtime_mutex = PTHREAD_MUTEX_STATIC_INITIALIZER;
-	static pthread_mutex_t gmtime_mutex = &_gmtime_mutex;
+	static pthread_mutex_t gmtime_mutex = PTHREAD_MUTEX_INITIALIZER;
 	static pthread_key_t gmtime_key = -1;
 	struct tm *p_tm;
 
-	pthread_mutex_lock(&gmtime_mutex);
-	if (gmtime_key < 0) {
-		if (pthread_key_create(&gmtime_key, free) < 0) {
-			pthread_mutex_unlock(&gmtime_mutex);
-			return(NULL);
+	if (__isthreaded != 0) {
+		_pthread_mutex_lock(&gmtime_mutex);
+		if (gmtime_key < 0) {
+			if (_pthread_key_create(&gmtime_key, free) < 0) {
+				_pthread_mutex_unlock(&gmtime_mutex);
+				return(NULL);
+			}
 		}
-	}
-	pthread_mutex_unlock(&gmtime_mutex);
-	/*
-	 * Changed to follow draft 4 pthreads standard, which
-	 * is what BSD currently has.
-	 */
-	if ((p_tm = pthread_getspecific(gmtime_key)) == NULL) {
-		if ((p_tm = (struct tm *)malloc(sizeof(struct tm))) == NULL) {
-			return(NULL);
+		_pthread_mutex_unlock(&gmtime_mutex);
+		/*
+		 * Changed to follow POSIX.1 threads standard, which
+		 * is what BSD currently has.
+		 */
+		if ((p_tm = _pthread_getspecific(gmtime_key)) == NULL) {
+			if ((p_tm = (struct tm *)malloc(sizeof(struct tm)))
+			    == NULL) {
+				return(NULL);
+			}
+			_pthread_setspecific(gmtime_key, p_tm);
 		}
-		pthread_setspecific(gmtime_key, p_tm);
+		gmtsub(timep, 0L, p_tm);
+		return(p_tm);
+	}
+	else {
+		gmtsub(timep, 0L, &tm);
+		return(&tm);
 	}
-	gmtsub(timep, 0L, p_tm);
-	return(p_tm);
-#else
-	gmtsub(timep, 0L, &tm);
-	return &tm;
-#endif
 }
 
 struct tm *
@@ -1635,14 +1607,10 @@ mktime(tmp)
 struct tm * const	tmp;
 {
 	time_t mktime_return_value;
-#ifdef	_THREAD_SAFE
-	pthread_mutex_lock(&lcl_mutex);
-#endif
+	_MUTEX_LOCK(&lcl_mutex);
 	tzset();
 	mktime_return_value = time1(tmp, localsub, 0L);
-#ifdef	_THREAD_SAFE
-	pthread_mutex_unlock(&lcl_mutex);
-#endif
+	_MUTEX_UNLOCK(&lcl_mutex);
 	return(mktime_return_value);
 }
 
diff --git a/lib/libc/stdtime/strftime.c b/lib/libc/stdtime/strftime.c
index cd506c1..83bddc9 100644
--- a/lib/libc/stdtime/strftime.c
+++ b/lib/libc/stdtime/strftime.c
@@ -30,6 +30,7 @@ static const char	elsieid[] = "@(#)strftime.c	7.38";
 #endif /* !defined NOID */
 #endif /* !defined lint */
 
+#include "namespace.h"
 #include "private.h"
 
 #ifndef LIBC_SCCS
@@ -41,6 +42,7 @@ static const char	sccsid[] = "@(#)strftime.c	5.4 (Berkeley) 3/14/89";
 #include "tzfile.h"
 #include <fcntl.h>
 #include <sys/stat.h>
+#include "un-namespace.h"
 #include "timelocal.h"
 
 static char *	_add P((const char *, char *, const char *));
diff --git a/lib/libc/stdtime/strptime.c b/lib/libc/stdtime/strptime.c
index ca4dcef..88d04ce 100644
--- a/lib/libc/stdtime/strptime.c
+++ b/lib/libc/stdtime/strptime.c
@@ -64,21 +64,18 @@ static char sccsid[] = "@(#)strptime.c	0.1 (Powerdog) 94/03/27";
 #endif /* !defined NOID */
 #endif /* not lint */
 
+#include "namespace.h"
 #include <time.h>
 #include <ctype.h>
 #include <string.h>
-#ifdef	_THREAD_SAFE
 #include <pthread.h>
-#include "pthread_private.h"
-#endif
+#include "un-namespace.h"
+#include "libc_private.h"
 #include "timelocal.h"
 
 static char * _strptime(const char *, const char *, struct tm *);
 
-#ifdef	_THREAD_SAFE
-static struct pthread_mutex	_gotgmt_mutexd = PTHREAD_MUTEX_STATIC_INITIALIZER;
-static pthread_mutex_t		gotgmt_mutex   = &_gotgmt_mutexd;
-#endif
+static pthread_mutex_t	gotgmt_mutex = PTHREAD_MUTEX_INITIALIZER;
 static int got_GMT;
 
 #define asizeof(a)	(sizeof (a) / sizeof ((a)[0]))
@@ -524,21 +521,19 @@ strptime(const char *buf, const char *fmt, struct tm *tm)
 {
 	char *ret;
 
-#ifdef	_THREAD_SAFE
-	pthread_mutex_lock(&gotgmt_mutex);
-#endif
+	if (__isthreaded)
+		_pthread_mutex_lock(&gotgmt_mutex);
 
 	got_GMT = 0;
 	ret = _strptime(buf, fmt, tm);
 	if (ret && got_GMT) {
 		time_t t = timegm(tm);
-	    localtime_r(&t, tm);
+		localtime_r(&t, tm);
 		got_GMT = 0;
 	}
 
-#ifdef	_THREAD_SAFE
-	pthread_mutex_unlock(&gotgmt_mutex);
-#endif
+	if (__isthreaded)
+		_pthread_mutex_unlock(&gotgmt_mutex);
 
 	return ret;
 }
diff --git a/lib/libc/stdtime/timelocal.c b/lib/libc/stdtime/timelocal.c
index 3a810ed..c39b956 100644
--- a/lib/libc/stdtime/timelocal.c
+++ b/lib/libc/stdtime/timelocal.c
@@ -26,6 +26,7 @@
  * $FreeBSD$
  */
 
+#include "namespace.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/syslimits.h>
@@ -34,6 +35,9 @@
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
+#include "un-namespace.h"
+
 #include "setlocale.h"
 #include "timelocal.h"
 
@@ -158,7 +162,7 @@ __time_load_locale(const char *name)
 	fd = _open(filename, O_RDONLY);
 	if (fd < 0)
 		goto no_locale;
-	if (fstat(fd, &st) != 0)
+	if (_fstat(fd, &st) != 0)
 		goto bad_locale;
 	if (st.st_size <= 0)
 		goto bad_locale;