From a0082928b0f4d8095404e769534ef0e9d4d35a54 Mon Sep 17 00:00:00 2001
From: Vortex <jp@drvortex.dev>
Date: Wed, 6 Mar 2024 08:08:33 -0600
Subject: [PATCH] Fixed File.readSync

---
 src/emulation/callbacks.ts | 11 -----------
 src/emulation/sync.ts      |  5 -----
 src/file.ts                | 17 +++++++++++------
 3 files changed, 11 insertions(+), 22 deletions(-)

diff --git a/src/emulation/callbacks.ts b/src/emulation/callbacks.ts
index 776f6ed91..cbd216c9d 100644
--- a/src/emulation/callbacks.ts
+++ b/src/emulation/callbacks.ts
@@ -146,11 +146,6 @@ open satisfies Omit<typeof Node.open, '__promisify__'>;
 
 /**
  * Asynchronously reads the entire contents of a file.
- * @example Usage example
- *   fs.readFile('/etc/passwd', function (err, data) {
- *     if (err) throw err;
- *     console.log(data);
- *   });
  * @param filename
  * @param options
  * @option options encoding The string encoding for the file contents. Defaults to `null`.
@@ -632,12 +627,6 @@ lutimes satisfies Omit<typeof Node.lutimes, '__promisify__'>;
  * Asynchronous `realpath`. The callback gets two arguments
  * `(err, resolvedPath)`. May use `process.cwd` to resolve relative paths.
  *
- * @example Usage example
- *   fs.realpath('/etc/passwd', function (err, resolvedPath) {
- *     if (err) throw err;
- *     console.log(resolvedPath);
- *   });
- *
  * @param path
  * @param callback
  */
diff --git a/src/emulation/sync.ts b/src/emulation/sync.ts
index ef5d37aab..154787b91 100644
--- a/src/emulation/sync.ts
+++ b/src/emulation/sync.ts
@@ -303,11 +303,6 @@ function _appendFileSync(fname: string, data: Uint8Array, flag: string, mode: nu
  * Asynchronously append data to a file, creating the file if it not yet
  * exists.
  *
- * @example Usage example
- *   fs.appendFile('message.txt', 'data to append', function (err) {
- *     if (err) throw err;
- *     console.log('The "data to append" was appended to file!');
- *   });
  * @param filename
  * @param data
  * @param options
diff --git a/src/file.ts b/src/file.ts
index 6c1b45815..e3c69ed34 100644
--- a/src/file.ts
+++ b/src/file.ts
@@ -623,14 +623,19 @@ export abstract class PreloadFile<T extends FileSystem> extends File {
 			throw new ApiError(ErrorCode.EPERM, 'File not opened with a readable mode.');
 		}
 		position ??= this.position;
-		const endRead = position + length;
-		if (endRead > this.stats.size) {
-			length = this.stats.size - position;
+		let end = position + length;
+		if (end > this.stats.size) {
+			end = position + Math.max(this.stats.size - position, 0);
 		}
-		buffer.set(this._buffer.slice(position, position + length), offset);
 		this.stats.atimeMs = Date.now();
-		this._position = position + length;
-		return this.buffer.length;
+		this._position = end;
+		const bytesRead = end - position;
+		if (bytesRead == 0) {
+			// No copy/read. Return immediatly for better performance
+			return bytesRead;
+		}
+		buffer.set(this._buffer.slice(position, end), offset);
+		return bytesRead;
 	}
 
 	/**