Promote the src/tools crate to the top-level workspace.

The 'src' and 'tests' top-level directories now contain tools sources
and integration tests for any of the library crates.

cranelift/src/utils.rs

@@ -0,0 +1,39 @@
+//! Utility functions.
+
+use std::path::Path;
+use std::fs::File;
+use std::io::{Result, Read};
+
+/// Read an entire file into a string.
+pub fn read_to_string<P: AsRef<Path>>(path: P) -> Result<String> {
+    let mut file = try!(File::open(path));
+    let mut buffer = String::new();
+    try!(file.read_to_string(&mut buffer));
+    Ok(buffer)
+}
+
+/// Look for a directive in a comment string.
+/// The directive is of the form "foo:" and should follow the leading `;` in the comment:
+///
+/// ; dominates: ebb3 ebb4
+///
+/// Return the comment text following the directive.
+pub fn match_directive<'a>(comment: &'a str, directive: &str) -> Option<&'a str> {
+    assert!(directive.ends_with(':'),
+            "Directive must include trailing colon");
+    let text = comment.trim_left_matches(';').trim_left();
+    if text.starts_with(directive) {
+        Some(text[directive.len()..].trim())
+    } else {
+        None
+    }
+}
+
+#[test]
+fn test_match_directive() {
+    assert_eq!(match_directive("; foo: bar  ", "foo:"), Some("bar"));
+    assert_eq!(match_directive(" foo:bar", "foo:"), Some("bar"));
+    assert_eq!(match_directive("foo:bar", "foo:"), Some("bar"));
+    assert_eq!(match_directive(";x foo: bar", "foo:"), None);
+    assert_eq!(match_directive(";;; foo: bar", "foo:"), Some("bar"));
+}