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

1 files changed, 55 insertions, 69 deletions

diff --git a/lib/libc/gen/ttyname.c b/lib/libc/gen/ttyname.c
index cb01870e3d3b..55fc91867223 100644
--- a/lib/libc/gen/ttyname.c
+++ b/lib/libc/gen/ttyname.c
@@ -29,12 +29,15 @@
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
+ * $FreeBSD$
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
 static char sccsid[] = "@(#)ttyname.c	8.2 (Berkeley) 1/27/94";
 #endif /* LIBC_SCCS and not lint */
 
+#include "namespace.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -42,42 +45,44 @@ static char sccsid[] = "@(#)ttyname.c	8.2 (Berkeley) 1/27/94";
 #include <stdlib.h>
 #include <termios.h>
 #include <unistd.h>
-#include <db.h>
 #include <string.h>
 #include <paths.h>
-
-#ifdef _THREAD_SAFE
 #include <pthread.h>
-#include "pthread_private.h"
-static struct pthread_mutex _ttyname_lockd = PTHREAD_MUTEX_STATIC_INITIALIZER;
-static pthread_mutex_t ttyname_lock = &_ttyname_lockd;
-static pthread_key_t ttyname_key;
-static int      ttyname_init = 0;
+#include "un-namespace.h"
+
+#include <db.h>
+#include "libc_private.h"
+
+static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV;
+static char *oldttyname __P((int, struct stat *));
+static char *ttyname_threaded(int fd);
+static char *ttyname_unthreaded(int fd);
 
-char           *
+static pthread_mutex_t	ttyname_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_key_t	ttyname_key;
+static int		ttyname_init = 0;
+
+char *
 ttyname(int fd)
 {
 	char           *ret;
 
-	if (_FD_LOCK(fd, FD_READ, NULL) == 0) {
-		ret = __ttyname_basic(fd);
-		_FD_UNLOCK(fd, FD_READ);
-	} else {
-		ret = NULL;
-	}
-
+	if (__isthreaded == 0)
+		ret = ttyname_unthreaded(fd);
+	else
+		ret = ttyname_threaded(fd);
 	return (ret);
 }
 
-char           *
-__ttyname_r_basic(int fd, char *buf, size_t len)
+char *
+ttyname_r(int fd, char *buf, size_t len)
 {
-	register struct dirent *dirp;
-	register DIR   *dp;
-	struct stat     dsb;
-	struct stat     sb;
-	char           *rval;
-	int             minlen;
+	struct dirent	*dirp;
+	DIR		*dp;
+	struct stat	dsb;
+	struct stat	sb;
+	char		*rval;
+	int		minlen;
 
 	rval = NULL;
 
@@ -85,7 +90,7 @@ __ttyname_r_basic(int fd, char *buf, size_t len)
 	if (!isatty(fd))
 		return (rval);
 	/* Must be a character device. */
-	if (_thread_sys_fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
+	if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
 		return (rval);
 	/* Must have enough room */
 	if (len <= sizeof(_PATH_DEV))
@@ -110,25 +115,27 @@ __ttyname_r_basic(int fd, char *buf, size_t len)
 	return (rval);
 }
 
-char           *
-__ttyname_basic(int fd)
+static char *
+ttyname_threaded(int fd)
 {
-	char           *buf;
+	char	*buf;
 
-	pthread_mutex_lock(&ttyname_lock);
 	if (ttyname_init == 0) {
-		if (pthread_key_create(&ttyname_key, free)) {
-			pthread_mutex_unlock(&ttyname_lock);
-			return (NULL);
+		_pthread_mutex_lock(&ttyname_lock);
+		if (ttyname_init == 0) {
+			if (_pthread_key_create(&ttyname_key, free)) {
+				_pthread_mutex_unlock(&ttyname_lock);
+				return (NULL);
+			}
+			ttyname_init = 1;
 		}
-		ttyname_init = 1;
+		_pthread_mutex_unlock(&ttyname_lock);
 	}
-	pthread_mutex_unlock(&ttyname_lock);
 
 	/* Must have thread specific data field to put data */
-	if ((buf = pthread_getspecific(ttyname_key)) == NULL) {
+	if ((buf = _pthread_getspecific(ttyname_key)) == NULL) {
 		if ((buf = malloc(sizeof(_PATH_DEV) + MAXNAMLEN)) != NULL) {
-			if (pthread_setspecific(ttyname_key, buf) != 0) {
+			if (_pthread_setspecific(ttyname_key, buf) != 0) {
 				free(buf);
 				return (NULL);
 			}
@@ -136,34 +143,16 @@ __ttyname_basic(int fd)
 			return (NULL);
 		}
 	}
-	return (__ttyname_r_basic(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN));
+	return (ttyname_r(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN));
 }
 
-char           *
-ttyname_r(int fd, char *buf, size_t len)
-{
-	char           *ret;
-
-	if (_FD_LOCK(fd, FD_READ, NULL) == 0) {
-		ret = __ttyname_r_basic(fd, buf, len);
-		_FD_UNLOCK(fd, FD_READ);
-	} else {
-		ret = NULL;
-	}
-	return (ret);
-}
-#else
-static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV;
-static char *oldttyname __P((int, struct stat *));
-
-char *
-ttyname(fd)
-	int fd;
+static char *
+ttyname_unthreaded(int fd)
 {
-	struct stat sb;
-	struct termios ttyb;
-	DB *db;
-	DBT data, key;
+	struct stat	sb;
+	struct termios	ttyb;
+	DB		*db;
+	DBT		data, key;
 	struct {
 		mode_t type;
 		dev_t dev;
@@ -173,7 +162,7 @@ ttyname(fd)
 	if (tcgetattr(fd, &ttyb) < 0)
 		return (NULL);
 	/* Must be a character device. */
-	if (fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
+	if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
 		return (NULL);
 
 	if ( (db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL)) ) {
@@ -194,13 +183,11 @@ ttyname(fd)
 }
 
 static char *
-oldttyname(fd, sb)
-	int fd;
-	struct stat *sb;
+oldttyname(int fd, struct stat *sb)
 {
-	register struct dirent *dirp;
-	register DIR *dp;
-	struct stat dsb;
+	struct dirent	*dirp;
+	struct stat	dsb;
+	DIR 		*dp;
 
 	if ((dp = opendir(_PATH_DEV)) == NULL)
 		return (NULL);
@@ -219,4 +206,3 @@ oldttyname(fd, sb)
 	(void)closedir(dp);
 	return (NULL);
 }
-#endif