fix(ext/node): verbose zlib error messages (#28831)

Author: littledivy

ext/node/lib.rs

@@ -397,6 +397,7 @@ deno_core::extension!(deno_node,
     ops::zlib::op_zlib_init,
     ops::zlib::op_zlib_reset,
     ops::zlib::op_zlib_crc32,
+    ops::zlib::op_zlib_err_msg,
     ops::zlib::brotli::op_brotli_compress,
     ops::zlib::brotli::op_brotli_compress_async,
     ops::zlib::brotli::op_create_brotli_compress,

ext/node/ops/zlib/mod.rs

@@ -288,6 +288,30 @@ pub fn op_zlib_close(#[cppgc] resource: &Zlib) -> Result<(), ZlibError> {
   Ok(())
 }
 
+#[op2]
+#[string]
+pub fn op_zlib_err_msg(
+  #[cppgc] resource: &Zlib,
+) -> Result<Option<String>, ZlibError> {
+  let mut zlib = resource.inner.borrow_mut();
+  let zlib = zlib.as_mut().ok_or(ZlibError::NotInitialized)?;
+
+  let msg = zlib.strm.msg;
+  if msg.is_null() {
+    return Ok(None);
+  }
+
+  // SAFETY: `msg` is a valid pointer to a null-terminated string.
+  let msg = unsafe {
+    std::ffi::CStr::from_ptr(msg)
+      .to_str()
+      .map_err(|_| JsErrorBox::type_error("invalid error message"))?
+      .to_string()
+  };
+
+  Ok(Some(msg))
+}
+
 #[allow(clippy::too_many_arguments)]
 #[op2(fast)]
 #[smi]

ext/node/polyfills/_zlib_binding.mjs

@@ -46,6 +46,7 @@ export const UNZIP = 7;
 import {
   op_zlib_close,
   op_zlib_close_if_pending,
+  op_zlib_err_msg,
   op_zlib_init,
   op_zlib_new,
   op_zlib_reset,
@@ -57,6 +58,7 @@ const writeResult = new Uint32Array(2);
 
 class Zlib {
   #handle;
+  #dictionary;
 
   constructor(mode) {
     this.#handle = op_zlib_new(mode);
@@ -104,7 +106,11 @@ class Zlib {
         // normal statuses, not fatal
         break;
       case Z_NEED_DICT:
-        this.#error("Bad dictionary", err);
+        if (this.#dictionary && this.#dictionary.length > 0) {
+          this.#error("Bad dictionary", err);
+        } else {
+          this.#error("Missing dictionary", err);
+        }
         return false;
       default:
         // something else.
@@ -160,6 +166,8 @@ class Zlib {
       dictionary ?? new Uint8Array(0),
     );
 
+    this.#dictionary = dictionary;
+
     if (err != Z_OK) {
       this.#error("Failed to initialize zlib", err);
     }
@@ -177,6 +185,7 @@ class Zlib {
   }
 
   #error(message, err) {
+    message = op_zlib_err_msg(this.#handle) ?? message;
     this.onerror(message, err);
     op_zlib_close_if_pending(this.#handle);
   }

tests/node_compat/config.jsonc

@@ -1322,6 +1322,7 @@
       "test-zlib-create-raw.js",
       "test-zlib-deflate-raw-inherits.js",
       "test-zlib-destroy-pipe.js",
+      "test-zlib-dictionary-fail.js",
       "test-zlib-empty-buffer.js",
       "test-zlib-flush-write-sync-interleaved.js",
       "test-zlib-from-string.js",

tests/node_compat/runner/TODO.md

@@ -2664,7 +2664,6 @@ NOTE: This file should not be manually edited. Please edit `tests/node_compat/co
 - [parallel/test-zlib-crc32.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-crc32.js)
 - [parallel/test-zlib-deflate-constructors.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-deflate-constructors.js)
 - [parallel/test-zlib-destroy.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-destroy.js)
-- [parallel/test-zlib-dictionary-fail.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-dictionary-fail.js)
 - [parallel/test-zlib-dictionary.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-dictionary.js)
 - [parallel/test-zlib-failed-init.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-failed-init.js)
 - [parallel/test-zlib-flush-drain-longblock.js](https://github.com/nodejs/node/tree/v23.9.0/test/parallel/test-zlib-flush-drain-longblock.js)

tests/node_compat/test/parallel/test-zlib-dictionary-fail.js

@@ -0,0 +1,67 @@
+// deno-fmt-ignore-file
+// deno-lint-ignore-file
+
+// Copyright Joyent and Node contributors. All rights reserved. MIT license.
+// Taken from Node 23.9.0
+// This file is automatically generated by `tests/node_compat/runner/setup.ts`. Do not modify this file manually.
+
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const zlib = require('zlib');
+
+// String "test" encoded with dictionary "dict".
+const input = Buffer.from([0x78, 0xBB, 0x04, 0x09, 0x01, 0xA5]);
+
+{
+  const stream = zlib.createInflate();
+
+  stream.on('error', common.mustCall(function(err) {
+    assert.match(err.message, /Missing dictionary/);
+  }));
+
+  stream.write(input);
+}
+
+{
+  const stream = zlib.createInflate({ dictionary: Buffer.from('fail') });
+
+  stream.on('error', common.mustCall(function(err) {
+    assert.match(err.message, /Bad dictionary/);
+  }));
+
+  stream.write(input);
+}
+
+{
+  const stream = zlib.createInflateRaw({ dictionary: Buffer.from('fail') });
+
+  stream.on('error', common.mustCall(function(err) {
+    // It's not possible to separate invalid dict and invalid data when using
+    // the raw format
+    assert.match(err.message, /(invalid|Operation-Ending-Supplemental Code is 0x12)/);
+  }));
+
+  stream.write(input);
+}