add ability for preamble to directory list

README.md

@@ -73,7 +73,8 @@ Agate by default supports TLSv1.2 and TLSv1.3. You can disable support for TLSv1
 ### Directory listing
 
 You can enable a basic directory listing for a directory by putting a file called `.directory-listing-ok` in that directory. This does not have an effect on sub-directories.
-The directory listing will hide files and directories whose name starts with a dot (e.g. the `.directory-listing-ok` file itself or also the `.meta` configuration file).
+This file must be UTF-8 encoded text; it may be empty. Any text in the file will be prepended to the directory listing.
+The directory listing will hide files and directories whose name starts with a dot (e.g. the `.directory-listing-ok` file itself, the `.meta` configuration file, or the `..` directory).
 
 A file called `index.gmi` will always take precedence over a directory listing.
 

src/main.rs

@@ -529,15 +529,12 @@ impl RequestHandle {
                 if url.path().ends_with('/') || url.path().is_empty() {
                     // if the path ends with a slash or the path is empty, the links will work the same
                     // without a redirect
+                    // use `push` instead of `join` because the changed path is used later
                     path.push("index.gmi");
                     if !path.exists() {
-                        if path.with_file_name(".directory-listing-ok").exists() {
-                            path.pop();
-                            return self.list_directory(&path).await;
-                        } else {
-                            self.send_header(51, "Directory index disabled.").await?;
-                            return Ok(());
-                        }
+                        path.pop();
+                        // try listing directory
+                        return self.list_directory(&path).await;
                     }
                 } else {
                     // if client is not redirected, links may not work as expected without trailing slash
@@ -601,8 +598,20 @@ impl RequestHandle {
             .add(b'{')
             .add(b'}');
 
+        // check if directory listing is enabled by geting preamble
+        let preamble = if let Ok(txt) = std::fs::read_to_string(path.join(".directory-listing-ok"))
+        {
+            txt
+        } else {
+            self.send_header(51, "Directory index disabled.").await?;
+            return Ok(());
+        };
+
         log::info!("Listing directory {:?}", path);
+
         self.send_header(20, "text/gemini").await?;
+        self.stream.write_all(preamble.as_bytes()).await?;
+
         let mut entries = tokio::fs::read_dir(path).await?;
         let mut lines = vec![];
         while let Some(entry) = entries.next_entry().await? {