fcntl(F_GETPATH) support

[christos%zoulas.com@localhost (Christos Zoulas)]

Comments?

christos


Index: kern/sys_descrip.c
===================================================================
RCS file: /cvsroot/src/sys/kern/sys_descrip.c,v
retrieving revision 1.34
diff -u -p -u -r1.34 sys_descrip.c
--- kern/sys_descrip.c	26 Aug 2019 10:19:08 -0000	1.34
+++ kern/sys_descrip.c	14 Sep 2019 21:33:29 -0000
@@ -315,6 +312,28 @@ do_fcntl_lock(int fd, int cmd, struct fl
 	return error;
 }
 
+static int
+do_fcntl_getpath(struct lwp *l, file_t *fp, char *upath)
+{
+	char *kpath;
+	int error;
+
+	if (fp->f_type != DTYPE_VNODE)
+		return EOPNOTSUPP;
+
+	kpath = PNBUF_GET();
+
+	error = vnode_to_path(kpath, MAXPATHLEN, fp->f_vnode, l, l->l_proc);
+	if (error)
+		goto out;
+
+	error = copyoutstr(kpath, upath, MAXPATHLEN, NULL);
+out:
+	PNBUF_PUT(kpath);
+
+	return error;
+}
+	
 /*
  * The file control system call.
  */
@@ -463,6 +482,10 @@ sys_fcntl(struct lwp *l, const struct sy
 		error = (*fp->f_ops->fo_ioctl)(fp, FIOSETOWN, &tmp);
 		break;
 
+	case F_GETPATH:
+		error = do_fcntl_getpath(l, fp, SCARG(uap, arg));
+		break;
+
 	default:
 		error = EINVAL;
 	}
Index: sys/fcntl.h
===================================================================
RCS file: /cvsroot/src/sys/sys/fcntl.h,v
retrieving revision 1.50
diff -u -p -u -r1.50 fcntl.h
--- sys/fcntl.h	20 Feb 2018 18:20:05 -0000	1.50
+++ sys/fcntl.h	14 Sep 2019 21:33:29 -0000
@@ -193,6 +195,7 @@
 #define	F_DUPFD_CLOEXEC	12		/* close on exec duplicated fd */
 #define	F_GETNOSIGPIPE	13		/* get SIGPIPE disposition */
 #define	F_SETNOSIGPIPE	14		/* set SIGPIPE disposition */
+#define	F_GETPATH	15		/* get pathname assosiated with file */
 #endif
 
 /* file descriptor flags (F_GETFD, F_SETFD) */