Import hyra expt

1 files changed, 83 insertions, 0 deletions

diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c
new file mode 100644
index 0000000..83924c6
--- /dev/null
+++ b/sys/kern/vfs_lookup.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT 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.
+ */
+
+#include <sys/namei.h>
+#include <sys/vnode.h>
+#include <sys/errno.h>
+#include <vm/dynalloc.h>
+#include <string.h>
+
+/*
+ * Convert a path to a vnode.
+ *
+ * @ndp: Nameidata containing the path and resulting
+ *       vnode.
+ *
+ * TODO: Add support for lookups with individual
+ *       path components
+ */
+int
+namei(struct nameidata *ndp)
+{
+    struct vnode *vp;
+    struct vop_lookup_args lookup_args;
+    const char *path = ndp->path;
+    int status;
+
+    if (path == NULL) {
+        return -EINVAL;
+    }
+
+    /* Path must start with "/" */
+    if (*path != '/') {
+        return -EINVAL;
+    }
+
+    /* Just return the root vnode if we can */
+    if (strcmp(path, "/") == 0) {
+        ndp->vp = g_root_vnode;
+        return 0;
+    }
+
+    /*
+     * Some filesystems (like initramfs) may only understand
+     * full paths, so try passing it through.
+     */
+    lookup_args.name = path;
+    lookup_args.dirvp = g_root_vnode;
+    lookup_args.vpp = &vp;
+    status = vfs_vop_lookup(lookup_args.dirvp, &lookup_args);
+
+    if (status != 0) {
+        return status;
+    }
+
+    ndp->vp = vp;
+    return 0;
+}