Initial reorg.

This is largely the same as #305, but updated for the current tree.

crates/wasi-common/src/fs/dir_builder.rs

@@ -0,0 +1,49 @@
+use std::{io, path::Path};
+
+/// A builder used to create directories in various manners.
+///
+/// This corresponds to [`std::fs::DirBuilder`].
+///
+/// TODO: Not yet implemented.
+///
+/// [`std::fs::DirBuilder`]: https://doc.rust-lang.org/std/fs/struct.DirBuilder.html
+pub struct DirBuilder {}
+
+impl DirBuilder {
+    /// Creates a new set of options with default mode/security settings for all platforms and also non-recursive.
+    ///
+    /// This corresponds to [`std::fs::DirBuilder::new`].
+    ///
+    /// TODO: Not yet implemented.
+    ///
+    /// [`std::fs::DirBuilder::new`]: https://doc.rust-lang.org/std/fs/struct.DirBuilder.html#method.new
+    pub fn new() -> Self {
+        unimplemented!("DirBuilder::new");
+    }
+
+    /// Indicates that directories should be created recursively, creating all parent directories.
+    ///
+    /// This corresponds to [`std::fs::DirBuilder::recursive`].
+    ///
+    /// TODO: Not yet implemented.
+    ///
+    /// [`std::fs::DirBuilder::recursive`]: https://doc.rust-lang.org/std/fs/struct.DirBuilder.html#method.recursive
+    pub fn recursive(&mut self, recursive: bool) -> &mut Self {
+        unimplemented!("DirBuilder::recursive");
+    }
+
+    /// Creates the specified directory with the options configured in this builder.
+    ///
+    /// This corresponds to [`std::fs::DirBuilder::create`].
+    ///
+    /// TODO: Not yet implemented.
+    ///
+    /// [`std::fs::DirBuilder::create`]: https://doc.rust-lang.org/std/fs/struct.DirBuilder.html#method.create
+    pub fn create<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
+        unimplemented!("DirBuilder::create");
+    }
+}
+
+// TODO: functions from DirBuilderExt?
+
+// TODO: impl Debug for DirBuilder