move Rust sources to top level, C sources into c_src

This moves the Rust sources out of rust_src/ and into the top level.
Running the bcachefs executable out of the development tree is now:

$ ./target/release/bcachefs command
or
$ cargo run --profile release -- command

instead of "./bcachefs command".

Building and installing is still:

$ make && make install

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/commands/cmd_completions.rs b/src/commands/cmd_completions.rs
new file mode 100644
index 00000000..53cdd643
--- /dev/null
+++ b/src/commands/cmd_completions.rs
@@ -0,0 +1,19 @@
+use clap::{Command, CommandFactory, Parser};
+use clap_complete::{generate, Generator, Shell};
+use std::io;
+
+/// Generate shell completions
+#[derive(clap::Parser, Debug)]
+pub struct Cli {
+    shell: Shell,
+}
+
+fn print_completions<G: Generator>(gen: G, cmd: &mut Command) {
+    generate(gen, cmd, cmd.get_name().to_string(), &mut io::stdout());
+}
+
+pub fn cmd_completions(argv: Vec<String>) -> i32 {
+    let cli = Cli::parse_from(argv);
+    print_completions(cli.shell, &mut super::Cli::command());
+    0
+}