From 08b9bf99a5cf1b510f8d85fdc99c96711b8e6d2c Mon Sep 17 00:00:00 2001
From: Robin Mueller <robin.mueller.m@gmail.com>
Date: Thu, 5 Sep 2024 00:25:02 +0200
Subject: [PATCH] remove last std dependency

---
 src/dest.rs      | 26 +++++++++-----------------
 src/filestore.rs | 22 ++++++++++++++++++++++
 2 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/src/dest.rs b/src/dest.rs
index 44d6933..1fe48fd 100644
--- a/src/dest.rs
+++ b/src/dest.rs
@@ -1,6 +1,5 @@
 use crate::{user::TransactionFinishedParams, DummyPduProvider, GenericSendError, PduProvider};
 use core::str::{from_utf8, from_utf8_unchecked, Utf8Error};
-use std::path::Path;
 
 use super::{
     filestore::{FilestoreError, NativeFilestore, VirtualFilestore},
@@ -696,7 +695,6 @@ impl<
             &self.tparams.file_properties.dest_file_name
                 [..self.tparams.file_properties.dest_file_name_len],
         )?;
-        //let dest_path = Path::new(dest_name);
         self.tparams.file_properties.dest_path_buf[0..dest_name.len()]
             .copy_from_slice(dest_name.as_bytes());
         self.tparams.file_properties.dest_file_path_len = dest_name.len();
@@ -732,30 +730,20 @@ impl<
         cfdp_user.metadata_recvd_indication(&metadata_recvd_params);
 
         if self.vfs.exists(dest_name)? && self.vfs.is_dir(dest_name)? {
-            // TODO: We require a VFS function to retrieve the file name from a full path to
-            // avoid the last std runtime dependency.
-
             // Create new destination path by concatenating the last part of the source source
             // name and the destination folder. For example, for a source file of /tmp/hello.txt
             // and a destination name of /home/test, the resulting file name should be
             // /home/test/hello.txt
             // Safety: It was already verified that the path is valid during the transaction start.
-            let source_path = Path::new(unsafe {
-                from_utf8_unchecked(
-                    //from_utf8(
-                    &self.tparams.file_properties.src_file_name
-                        [..self.tparams.file_properties.src_file_name_len],
-                )
-            });
-            let source_name = source_path.file_name();
-            if source_name.is_none() {
+            let source_file_name = self.vfs.file_name(src_name)?;
+            if source_file_name.is_none() {
                 return Err(DestError::PathConcat);
             }
-            let source_name = source_name.unwrap();
+            let source_name = source_file_name.unwrap();
             self.tparams.file_properties.dest_path_buf[dest_name.len()] = b'/';
             self.tparams.file_properties.dest_path_buf
                 [dest_name.len() + 1..dest_name.len() + 1 + source_name.len()]
-                .copy_from_slice(source_name.as_encoded_bytes());
+                .copy_from_slice(source_name.as_bytes());
             self.tparams.file_properties.dest_file_path_len += 1 + source_name.len();
         }
         let dest_path_str = from_utf8(
@@ -909,7 +897,11 @@ mod tests {
     use core::{cell::Cell, sync::atomic::AtomicBool};
     #[allow(unused_imports)]
     use std::println;
-    use std::{fs, path::PathBuf, string::String};
+    use std::{
+        fs,
+        path::{Path, PathBuf},
+        string::String,
+    };
 
     use alloc::{sync::Arc, vec::Vec};
     use rand::Rng;
diff --git a/src/filestore.rs b/src/filestore.rs
index a6886a4..ed17812 100644
--- a/src/filestore.rs
+++ b/src/filestore.rs
@@ -9,6 +9,7 @@ use std::path::Path;
 pub use std_mod::*;
 
 #[derive(Debug, Clone)]
+#[non_exhaustive]
 pub enum FilestoreError {
     FileDoesNotExist,
     FileAlreadyExists,
@@ -22,6 +23,8 @@ pub enum FilestoreError {
         string: String,
     },
     ChecksumTypeNotImplemented(ChecksumType),
+    Utf8Error,
+    Other,
 }
 
 impl From<ByteConversionError> for FilestoreError {
@@ -64,6 +67,12 @@ impl Display for FilestoreError {
             FilestoreError::ChecksumTypeNotImplemented(checksum_type) => {
                 write!(f, "checksum {:?} not implemented", checksum_type)
             }
+            FilestoreError::Utf8Error => {
+                write!(f, "utf8 error")
+            }
+            FilestoreError::Other => {
+                write!(f, "some filestore error occured")
+            }
         }
     }
 }
@@ -128,6 +137,8 @@ pub trait VirtualFilestore {
 
     fn exists(&self, path: &str) -> Result<bool, FilestoreError>;
 
+    fn file_name<'a>(&self, full_path: &'a str) -> Result<Option<&'a str>, FilestoreError>;
+
     fn file_size(&self, path: &str) -> Result<u64, FilestoreError>;
 
     /// This special function is the CFDP specific abstraction to calculate the checksum of a file.
@@ -201,6 +212,17 @@ pub mod std_mod {
             Ok(())
         }
 
+        fn file_name<'a>(&self, full_path: &'a str) -> Result<Option<&'a str>, FilestoreError> {
+            if self.is_dir(full_path)? {
+                return Err(FilestoreError::IsNotFile);
+            }
+            let path = Path::new(full_path);
+
+            path.file_name()
+                .map(|s| s.to_str())
+                .ok_or(FilestoreError::Utf8Error)
+        }
+
         fn truncate_file(&self, file_path: &str) -> Result<(), FilestoreError> {
             if !self.exists(file_path)? {
                 return Err(FilestoreError::FileDoesNotExist);