--- MiNT/src/unifs.c	2018/04/24 17:56:34	1.1.1.3
+++ MiNT/src/unifs.c	2018/04/24 17:57:22	1.1.1.4
@@ -2,7 +2,7 @@
 
 Copyright 1991,1992 Eric R. Smith.
 
-Copyright 1992 Atari Corporation.
+Copyright 1992,1993 Atari Corporation.
 
 All rights reserved.
 
@@ -66,6 +66,8 @@ static long	ARGS_ON_STACK uni_symlink	P_
 
 static long	ARGS_ON_STACK uni_readlink	P_((fcookie *fc, char *buf, int buflen));
 
+static long	ARGS_ON_STACK uni_fscntl	P_((fcookie *dir, const char *name, int cmd, long arg));
+
 
 
 FILESYS uni_filesys = {
@@ -86,7 +88,7 @@ FILESYS uni_filesys = {
 
 	uni_pathconf, uni_dfree, nowritelabel, noreadlabel,
 
-	uni_symlink, uni_readlink, nohardlink, nofscntl, nodskchng
+	uni_symlink, uni_readlink, nohardlink, uni_fscntl, nodskchng
 
 };
 
@@ -1232,3 +1234,321 @@ uni_readlink(fc, buf, buflen)
 
 }
 
+
+
+
+
+
+
+
+
+/* uk: use these Dcntl's to install a new filesystem which is only visible
+
+ *     on drive u:
+
+ *
+
+ *     FS_INSTALL:   let the kernel know about the file system; it does NOT
+
+ *                   get a device number.
+
+ *     FS_MOUNT:     use Dcntl(FS_MOUNT, "u:\\foo", &descr) to make a directory
+
+ *                   foo where the filesytem resides in; the file system now
+
+ *                   gets its device number which is also written into the
+
+ *                   dev_no field of the fs_descr structure.
+
+ *     FS_UNMOUNT:   remove a file system's directory; this call closes all
+
+ *                   open files, directory searches and directories on this
+
+ *                   device. Make sure that the FS will not recognise any
+
+ *                   accesses to this device, as fs->root will be called
+
+ *                   during the reinitalisation!
+
+ *     FS_UNINSTALL: remove a file system completely from the kernel list,
+
+ *                   but that will only be possible if there is no directory
+
+ *                   associated with this file system.
+
+ *                   This function allows it to write file systems as demons
+
+ *                   which stay in memory only as long as needed.
+
+ *
+
+ * BUG: it is not possible yet to lock such a filesystem.
+
+ */
+
+
+
+/* here we start with gemdos only file system device numbers */
+
+static curr_dev_no = 0x100;
+
+
+
+
+
+
+
+static long ARGS_ON_STACK
+
+uni_fscntl(dir, name, cmd, arg)
+
+	fcookie *dir;
+
+	const char *name;
+
+	int cmd;
+
+	long arg;
+
+{
+
+	fcookie fc;
+
+	long r;
+
+
+
+	extern struct kerinfo kernelinfo;
+
+	extern FILESYS *active_fs;
+
+
+
+	if (cmd == FS_INSTALL) { /* install a new filesystem */
+
+		struct fs_descr *d = (struct fs_descr*)arg;
+
+		FILESYS *fs;
+
+
+
+	/* check if FS is installed already */
+
+		for (fs = active_fs;  fs;  fs = fs->next)
+
+			if (d->file_system == fs)  return 0L;
+
+	/* include new file system into chain of file systems */
+
+		d->file_system->next = active_fs;
+
+		active_fs = d->file_system;
+
+		return (long)&kernelinfo;  /* return pointer to kernel info as OK */
+
+	} else if (cmd == FS_MOUNT) {  /* install a new gemdos-only device for this FS */
+
+		struct fs_descr *d = (struct fs_descr*)arg;
+
+		FILESYS *fs;
+
+		UNIFILE *u;
+
+
+
+	/* first check for existing names */
+
+		r = uni_lookup(dir, name, &fc);
+
+		if (r == 0) {
+
+			release_cookie(&fc);
+
+			return EACCDN;   /* name exists already */
+
+		}
+
+		if (r != EFILNF) return r; /* some other error */
+
+		if (!d) return EACCDN;
+
+		if (!d->file_system) return EACCDN;
+
+	/* check if FS is installed */
+
+		for (fs = active_fs;  fs;  fs = fs->next)
+
+			if (d->file_system == fs)  break;
+
+		if (!fs) return EACCDN;  /* not installed, so return an error */
+
+		u = kmalloc(SIZEOF(UNIFILE));
+
+		if (!u) return EACCDN;
+
+		strncpy(u->name, name, NAME_MAX);
+
+		u->name[NAME_MAX] = 0;
+
+		u->mode = S_IFDIR|DEFAULT_DIRMODE;
+
+		u->data = 0;
+
+		u->fs = d->file_system;
+
+	/* now get the file system its own device number */
+
+		u->dev = d->dev_no = curr_dev_no++;
+
+	/* chain new entry into unifile list */
+
+		u->next = u_root;
+
+		u_root = u;
+
+		return (long)u->dev;
+
+	} else if (cmd == FS_UNMOUNT) {  /* remove a file system's directory */
+
+		struct fs_descr *d = (struct fs_descr*)arg;
+
+		FILESYS *fs;
+
+		UNIFILE *u;
+
+
+
+	/* first check that directory exists */
+
+		r = uni_lookup(dir, name, &fc);
+
+		if (r != 0)  return EFILNF;   /* name does not exist */
+
+		if (!d) return EFILNF;
+
+		if (!d->file_system) return EFILNF;
+
+		if (d->file_system != fc.fs)
+
+			return EFILNF;  /* not the right name! */
+
+		u = (UNIFILE*)fc.index;
+
+		release_cookie(&fc);
+
+		if (!u || (u->fs != d->file_system))
+
+			return EFILNF;
+
+	/* check if FS is installed */
+
+		for (fs = active_fs;  fs;  fs = fs->next)
+
+			if (d->file_system == fs)  break;
+
+		if (!fs) return EACCDN;  /* not installed, so return an error */
+
+
+
+	/* here comes the difficult part: we have to close all files on that
+
+	 * device, so we have to call changedrv(). The file system driver
+
+	 * has to make sure that further calls to fs.root() with this device
+
+	 * number will fail!
+
+	 *
+
+	 * Kludge: mark the directory as a link, so uni_remove will remove it.
+
+	 */
+
+		changedrv(u->dev);
+
+		u->mode &= ~S_IFMT;
+
+		u->mode |= S_IFLNK;
+
+		return uni_remove(dir, name);
+
+	} else if (cmd == FS_UNINSTALL) {    /* remove file system from kernel list */
+
+		struct fs_descr *d = (struct fs_descr*)arg;
+
+		FILESYS *fs, *last_fs;
+
+		UNIFILE *u;
+
+
+
+	/* first check if there are any files or directories associated with
+
+	 * this file system
+
+	 */
+
+		for (u = u_root;  u;  u = u->next)
+
+			if (u->fs == d->file_system)
+
+				return EACCDN;   /* we cannot remove it before unmount */
+
+		last_fs = 0;
+
+		fs = active_fs;
+
+		while (fs)  {   /* go through the list and remove the file system */
+
+			if (fs == d->file_system)  {
+
+				if (last_fs)
+
+					last_fs->next = fs->next;
+
+				else
+
+					active_fs = fs->next;
+
+				d->file_system->next = 0;
+
+				return 0;
+
+			}
+
+			last_fs = fs;
+
+			fs = fs->next;
+
+		}
+
+		return EFILNF;
+
+	} else {
+
+	/* see if we should just pass this along to another file system */
+
+		r = uni_lookup(dir, name, &fc);
+
+		if (r == 0) {
+
+			if (fc.fs != &uni_filesys) {
+
+				r = (*fc.fs->fscntl)(&fc, ".", cmd, arg);
+
+				release_cookie(&fc);
+
+				return r;
+
+			}
+
+			release_cookie(&fc);
+
+		}
+
+	}
+
+	return EINVFN;
+
+}
+