First basic implementation of aggregation; symlinks are not handled yet

1 files changed, 64 insertions, 3 deletions

diff --git a/src/lib.rs b/src/lib.rs
index fd4cb89..5d22577 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,8 +1,69 @@
 extern crate failure;
 extern crate jwalk;
 
-use failure::Error;
+pub struct WalkOptions {
+    pub threads: usize,
+}
+
+impl WalkOptions {
+    pub fn iter_from_path(&self, path: &Path) -> WalkDir {
+        WalkDir::new(path)
+            .preload_metadata(true)
+            .skip_hidden(false)
+            .num_threads(self.threads)
+    }
+}
+
+#[derive(Default)]
+pub struct WalkResult {
+    pub num_errors: usize,
+}
 
-pub fn fun() -> Result<(), Error> {
-    unimplemented!();
+impl fmt::Display for WalkResult {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(f, "Encountered {} IO errors", self.num_errors)
+    }
 }
+
+mod aggregate {
+    use crate::{WalkOptions, WalkResult};
+    use failure::Error;
+    use std::io;
+    use std::path::Path;
+
+    pub fn aggregate(
+        mut out: impl io::Write,
+        options: WalkOptions,
+        paths: impl IntoIterator<Item = impl AsRef<Path>>,
+    ) -> Result<WalkResult, Error> {
+        let mut res = WalkResult::default();
+        for path in paths.into_iter() {
+            let mut num_bytes = 0u64;
+            for entry in options.iter_from_path(path.as_ref()) {
+                match entry {
+                    Ok(entry) => {
+                        num_bytes += match entry.metadata {
+                            Some(Ok(m)) => m.len(),
+                            Some(Err(_)) => {
+                                res.num_errors += 1;
+                                0
+                            }
+                            None => unreachable!(
+                                "we ask for metadata, so we at least have Some(Err(..)))"
+                            ),
+                        };
+                    }
+                    Err(_) => res.num_errors += 1,
+                }
+            }
+
+            writeln!(out, "{}\t{}", num_bytes, path.as_ref().display())?;
+        }
+        Ok(res)
+    }
+}
+
+pub use aggregate::aggregate;
+use jwalk::WalkDir;
+use std::fmt;
+use std::path::Path;