Have ttyname_r() try to ask DEVFS for the device name.

Document ttyname_r().

Simplify threaded/unthreaded stuff a lot.

2 files changed, 16 insertions, 35 deletions

diff --git a/lib/libc/gen/ttyname.3 b/lib/libc/gen/ttyname.3
index 324ebb1..dcea14a 100644
--- a/lib/libc/gen/ttyname.3
+++ b/lib/libc/gen/ttyname.3
@@ -46,6 +46,8 @@
 .In unistd.h
 .Ft char *
 .Fn ttyname "int fd"
+.Ft char *
+.Fn ttyname_r "int fd" "char *buf" "size_t len"
 .Ft int
 .Fn isatty "int fd"
 .Ft int
diff --git a/lib/libc/gen/ttyname.c b/lib/libc/gen/ttyname.c
index e4a0ed4..5630442 100644
--- a/lib/libc/gen/ttyname.c
+++ b/lib/libc/gen/ttyname.c
@@ -40,6 +40,8 @@ __FBSDID("$FreeBSD$");
 #include "namespace.h"
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/filio.h>
 #include <fcntl.h>
 #include <dirent.h>
 #include <stdlib.h>
@@ -52,33 +54,21 @@ __FBSDID("$FreeBSD$");
 
 #include "libc_private.h"
 
-static char buf[sizeof(_PATH_DEV) + MAXNAMLEN];
-static char *ttyname_threaded(int fd);
-static char *ttyname_unthreaded(int fd);
+static char ttyname_buf[sizeof(_PATH_DEV) + MAXNAMLEN];
 
 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 (__isthreaded == 0)
-		ret = ttyname_unthreaded(fd);
-	else
-		ret = ttyname_threaded(fd);
-	return (ret);
-}
-
-char *
 ttyname_r(int fd, char *buf, size_t len)
 {
 	struct stat	sb;
 	char		*rval;
+	struct fiodgname_arg fgn;
 
 	rval = NULL;
+	*buf = '\0';
 
 	/* Must be a terminal. */
 	if (!isatty(fd))
@@ -91,16 +81,23 @@ ttyname_r(int fd, char *buf, size_t len)
 		return (rval);
 
 	strcpy(buf, _PATH_DEV);
+	fgn.len = len - strlen(buf);
+	fgn.buf = buf + strlen(buf);
+	if (!_ioctl(fd, FIODGNAME, &fgn))
+		return(buf);
 	devname_r(sb.st_rdev, S_IFCHR,
 	    buf + strlen(buf), sizeof(buf) - strlen(buf));
 	return (buf);
 }
 
-static char *
-ttyname_threaded(int fd)
+char *
+ttyname(int fd)
 {
 	char	*buf;
 
+	if (__isthreaded == 0)
+		return (ttyname_r(fd, ttyname_buf, sizeof ttyname_buf));
+
 	if (ttyname_init == 0) {
 		_pthread_mutex_lock(&ttyname_lock);
 		if (ttyname_init == 0) {
@@ -127,21 +124,3 @@ ttyname_threaded(int fd)
 	return (ttyname_r(fd, buf, sizeof(_PATH_DEV) + MAXNAMLEN));
 }
 
-static char *
-ttyname_unthreaded(int fd)
-{
-	struct stat	sb;
-	struct termios	ttyb;
-
-	/* Must be a terminal. */
-	if (tcgetattr(fd, &ttyb) < 0)
-		return (NULL);
-	/* Must be a character device. */
-	if (_fstat(fd, &sb) || !S_ISCHR(sb.st_mode))
-		return (NULL);
-
-	strcpy(buf, _PATH_DEV);
-	devname_r(sb.st_rdev, S_IFCHR,
-	    buf + strlen(buf), sizeof(buf) - strlen(buf));
-	return (buf);
-}