not_before: introduce enum to clarify API

trussed-dev · Mar 28, 2024 · 06d0c6f · 06d0c6f
1 parent 2950600
commit 06d0c6f
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Showing 4 changed files with 41 additions and 23 deletions.
diff --git a/src/api.rs b/src/api.rs
@@ -17,6 +17,32 @@ mod macros;
 //
 // At minimum, we don't want to list the indices (may need proc-macro)
 
+#[derive(Clone, Eq, PartialEq, Debug, serde::Serialize, serde::Deserialize)]
+pub enum NotBefore {
+    /// Start iteration at the beginning of the directory
+    None,
+    /// Start iteration at an exact match with the provided filename
+    Filename(PathBuf),
+    /// Start iteration at the first path that is "after" the provided filename
+    FilenamePart(PathBuf),
+}
+
+impl NotBefore {
+    pub fn with_filename(value: Option<PathBuf>) -> Self {
+        match value {
+            None => Self::None,
+            Some(p) => Self::Filename(p),
+        }
+    }
+
+    pub fn with_filename_part(value: Option<PathBuf>) -> Self {
+        match value {
+            None => Self::None,
+            Some(p) => Self::FilenamePart(p),
+        }
+    }
+}
+
 generate_enums! {
 
     ////////////
@@ -244,7 +270,7 @@ pub mod request {
         ReadDirFirst:
           - location: Location
           - dir: PathBuf
-          - not_before: Option<(PathBuf, bool)>
+          - not_before: NotBefore
 
         ReadDirNext:
 

diff --git a/src/client.rs b/src/client.rs
@@ -610,7 +610,7 @@ pub trait FilesystemClient: PollClient {
         self.request(request::ReadDirFirst {
             location,
             dir,
-            not_before: not_before_filename.map(|p| (p, true)),
+            not_before: NotBefore::with_filename(not_before_filename),
         })
     }
 
@@ -630,7 +630,7 @@ pub trait FilesystemClient: PollClient {
         self.request(request::ReadDirFirst {
             location,
             dir,
-            not_before: not_before_filename.map(|p| (p, false)),
+            not_before: NotBefore::with_filename_part(not_before_filename),
         })
     }
 

diff --git a/src/service.rs b/src/service.rs
@@ -409,10 +409,7 @@ impl<P: Platform> ServiceResources<P> {
                 let maybe_entry = match filestore.read_dir_first(
                     &request.dir,
                     request.location,
-                    request
-                        .not_before
-                        .as_ref()
-                        .map(|(path, require_equal)| (&**path, *require_equal)),
+                    &request.not_before,
                 )? {
                     Some((entry, read_dir_state)) => {
                         ctx.read_dir_state = Some(read_dir_state);

diff --git a/src/store/filestore.rs b/src/store/filestore.rs
@@ -1,6 +1,7 @@
 use core::cmp::Ordering;
 
 use crate::{
+    api::NotBefore,
     error::{Error, Result},
     // service::ReadDirState,
     store::{self, DynFilesystem, Store},
@@ -119,7 +120,7 @@ pub trait Filestore {
         &mut self,
         dir: &Path,
         location: Location,
-        not_before: Option<(&Path, bool)>,
+        not_before: &NotBefore,
     ) -> Result<Option<(DirEntry, ReadDirState)>>;
 
     /// Continue iterating over entries of a directory.
@@ -155,7 +156,7 @@ impl<S: Store> ClientFilestore<S> {
         &mut self,
         clients_dir: &Path,
         location: Location,
-        not_before: Option<(&Path, bool)>,
+        not_before: &NotBefore,
     ) -> Result<Option<(DirEntry, ReadDirState)>> {
         let fs = self.store.fs(location);
         let dir = self.actual_path(clients_dir)?;
@@ -172,19 +173,13 @@ impl<S: Store> ClientFilestore<S> {
                     // Option<usize, Result<DirEntry>> -> ??
                     .map(|(i, entry)| (i, entry.unwrap()))
                     // if there is a "not_before" entry, skip all entries before it.
-                    .find(|(_, entry)| {
-                        if let Some((not_before, require_equal)) = not_before {
-                            if require_equal {
-                                entry.file_name() == not_before
-                            } else {
-                                match entry.file_name().cmp_str(not_before) {
-                                    Ordering::Less => false,
-                                    Ordering::Equal | Ordering::Greater => true,
-                                }
-                            }
-                        } else {
-                            true
-                        }
+                    .find(|(_, entry)| match not_before {
+                        NotBefore::None => true,
+                        NotBefore::Filename(path) => entry.file_name() == &**path,
+                        NotBefore::FilenamePart(path) => match entry.file_name().cmp_str(path) {
+                            Ordering::Less => false,
+                            Ordering::Equal | Ordering::Greater => true,
+                        },
                     })
                     // if there is an entry, construct the state that needs storing out of it,
                     // remove the prefix from the entry's path to not leak implementation details to
@@ -446,7 +441,7 @@ impl<S: Store> Filestore for ClientFilestore<S> {
         &mut self,
         clients_dir: &Path,
         location: Location,
-        not_before: Option<(&Path, bool)>,
+        not_before: &NotBefore,
     ) -> Result<Option<(DirEntry, ReadDirState)>> {
         self.read_dir_first_impl(clients_dir, location, not_before)
     }