Lots more updates

Also begin adding rust building capabilities
to be able to write rust binaries for some commands.

rust/lib/common/src/proc/util.rs

@@ -0,0 +1,31 @@
+use super::Command;
+use std::borrow::Cow;
+
+use shell_quote::Quote;
+
+pub fn command_to_string(cmd: &Command) -> String {
+    let program = escape_cli(cmd.get_program());
+    let env: Vec<_> = cmd
+        .get_envs()
+        .map(|(key, value)| match value {
+            None => key.into(),
+            Some(value) => Cow::Owned(format!(
+                "{key}={value} ",
+                value = escape_cli(value.as_potentially_redacted_str())
+            )),
+        })
+        .collect();
+    let args: Vec<_> = cmd.get_args().map(escape_cli).collect();
+    let env = env.join("");
+    let args = args.join(" ");
+    format!(
+        "{env_marker}{env}{program}{arg_separator}{args}",
+        env_marker = if env.is_empty() { "" } else { "env " },
+        arg_separator = if args.is_empty() { "" } else { " " }
+    )
+}
+
+fn escape_cli<A: AsRef<str>>(str: A) -> String {
+    let str = str.as_ref();
+    shell_quote::Bash::quote(str)
+}