commit 3de0f7485272036cb4e87e392423da01897710b1
parent 9ba4d97f23063c8ddc41b65b9a3faf83b57a791b
Author: Kagami Sascha Rosylight <krosylight@proton.me>
Date: Mon, 20 Oct 2025 12:55:19 +0000
Bug 1994230 - Part 4: Split Zstd algorithms to a separate file r=smaug
Differential Revision: https://phabricator.services.mozilla.com/D268589
Diffstat:
4 files changed, 193 insertions(+), 145 deletions(-)
diff --git a/dom/compression/DecompressionStream.cpp b/dom/compression/DecompressionStream.cpp
@@ -8,6 +8,7 @@
#include "BaseAlgorithms.h"
#include "FormatZlib.h"
+#include "FormatZstd.h"
#include "js/TypeDecls.h"
#include "mozilla/Assertions.h"
#include "mozilla/StaticPrefs_dom.h"
@@ -17,155 +18,10 @@
#include "mozilla/dom/TransformStream.h"
#include "mozilla/dom/UnionTypes.h"
#include "mozilla/dom/WritableStream.h"
-#include "zstd/zstd.h"
namespace mozilla::dom {
using namespace compression;
-// See the zstd manual in https://facebook.github.io/zstd/zstd_manual.html or in
-// https://searchfox.org/mozilla-central/source/third_party/zstd/lib/zstd.h
-class ZstdDecompressionStreamAlgorithms : public DecompressionStreamAlgorithms {
- public:
- NS_DECL_ISUPPORTS_INHERITED
- NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ZstdDecompressionStreamAlgorithms,
- DecompressionStreamAlgorithms)
-
- static Result<already_AddRefed<ZstdDecompressionStreamAlgorithms>, nsresult>
- Create() {
- RefPtr<ZstdDecompressionStreamAlgorithms> alg =
- new ZstdDecompressionStreamAlgorithms();
- MOZ_TRY(alg->Init());
- return alg.forget();
- }
-
- private:
- ZstdDecompressionStreamAlgorithms() = default;
-
- [[nodiscard]] nsresult Init() {
- mDStream = ZSTD_createDStream();
- if (!mDStream) {
- return NS_ERROR_OUT_OF_MEMORY;
- }
-
- // Refuse any frame requiring larger than (1 << WINDOW_LOG_MAX) window size.
- // Note: 1 << 23 == 8 * 1024 * 1024
- static const uint8_t WINDOW_LOG_MAX = 23;
- ZSTD_DCtx_setParameter(mDStream, ZSTD_d_windowLogMax, WINDOW_LOG_MAX);
-
- return NS_OK;
- }
-
- // Shared by:
- // https://wicg.github.io/compression/#decompress-and-enqueue-a-chunk
- // https://wicg.github.io/compression/#decompress-flush-and-enqueue
- // All data errors throw TypeError by step 2: If this results in an error,
- // then throw a TypeError.
- MOZ_CAN_RUN_SCRIPT void DecompressAndEnqueue(
- JSContext* aCx, Span<const uint8_t> aInput, Flush aFlush,
- TransformStreamDefaultController& aController,
- ErrorResult& aRv) override {
- MOZ_ASSERT_IF(aFlush == Flush::Yes, !aInput.Length());
-
- if (mObservedStreamEnd && aInput.Length() > 0) {
- aRv.ThrowTypeError("Unexpected input after the end of stream");
- return;
- }
-
- ZSTD_inBuffer inBuffer = {
- /* src */ const_cast<uint8_t*>(aInput.Elements()),
- /* size */ aInput.Length(),
- /* pos */ 0};
-
- JS::RootedVector<JSObject*> array(aCx);
-
- while (inBuffer.pos < inBuffer.size && !mObservedStreamEnd) {
- UniquePtr<uint8_t[], JS::FreePolicy> buffer(
- static_cast<uint8_t*>(JS_malloc(aCx, kBufferSize)));
- if (!buffer) {
- aRv.ThrowTypeError("Out of memory");
- return;
- }
-
- ZSTD_outBuffer outBuffer = {/* dst */ buffer.get(),
- /* size */ kBufferSize,
- /* pos */ 0};
-
- size_t rv = ZSTD_decompressStream(mDStream, &outBuffer, &inBuffer);
- if (ZSTD_isError(rv)) {
- aRv.ThrowTypeError("zstd decompression error: "_ns +
- nsDependentCString(ZSTD_getErrorName(rv)));
- return;
- }
-
- if (rv == 0) {
- mObservedStreamEnd = true;
- }
-
- // Step 3: If buffer is empty, return.
- // (We'll implicitly return when the array is empty.)
-
- // Step 4: Split buffer into one or more non-empty pieces and convert them
- // into Uint8Arrays.
- // (The buffer is 'split' by having a fixed sized buffer above.)
-
- size_t written = outBuffer.pos;
- if (written > 0) {
- JS::Rooted<JSObject*> view(aCx, nsJSUtils::MoveBufferAsUint8Array(
- aCx, written, std::move(buffer)));
- if (!view || !array.append(view)) {
- JS_ClearPendingException(aCx);
- aRv.ThrowTypeError("Out of memory");
- return;
- }
- }
- }
-
- // Step 5: For each Uint8Array array, enqueue array in ds's transform.
- for (const auto& view : array) {
- JS::Rooted<JS::Value> value(aCx, JS::ObjectValue(*view));
- aController.Enqueue(aCx, value, aRv);
- if (aRv.Failed()) {
- return;
- }
- }
-
- // Step 6: If the end of the compressed input has been reached, and ds's
- // context has not fully consumed chunk, then throw a TypeError.
- if (mObservedStreamEnd && inBuffer.pos < inBuffer.size) {
- aRv.ThrowTypeError("Unexpected input after the end of stream");
- return;
- }
-
- // Step 3 of
- // https://wicg.github.io/compression/#decompress-flush-and-enqueue
- // If the end of the compressed input has not been reached, then throw a
- // TypeError.
- if (aFlush == Flush::Yes && !mObservedStreamEnd) {
- aRv.ThrowTypeError("The input is ended without reaching the stream end");
- return;
- }
- }
-
- ~ZstdDecompressionStreamAlgorithms() override {
- if (mDStream) {
- ZSTD_freeDStream(mDStream);
- mDStream = nullptr;
- }
- }
-
- ZSTD_DStream* mDStream = nullptr;
- bool mObservedStreamEnd = false;
-};
-
-NS_IMPL_CYCLE_COLLECTION_INHERITED(ZstdDecompressionStreamAlgorithms,
- DecompressionStreamAlgorithms)
-NS_IMPL_ADDREF_INHERITED(ZstdDecompressionStreamAlgorithms,
- DecompressionStreamAlgorithms)
-NS_IMPL_RELEASE_INHERITED(ZstdDecompressionStreamAlgorithms,
- DecompressionStreamAlgorithms)
-NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ZstdDecompressionStreamAlgorithms)
-NS_INTERFACE_MAP_END_INHERITING(DecompressionStreamAlgorithms)
-
/*
* Constructs either a ZLibDecompressionStreamAlgorithms or a
* ZstdDecompressionStreamAlgorithms, based on the CompressionFormat.
diff --git a/dom/compression/FormatZstd.cpp b/dom/compression/FormatZstd.cpp
@@ -0,0 +1,142 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "FormatZstd.h"
+
+#include "BaseAlgorithms.h"
+#include "mozilla/dom/TransformStreamDefaultController.h"
+#include "zstd/zstd.h"
+
+namespace mozilla::dom::compression {
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(ZstdDecompressionStreamAlgorithms,
+ DecompressionStreamAlgorithms)
+NS_IMPL_ADDREF_INHERITED(ZstdDecompressionStreamAlgorithms,
+ DecompressionStreamAlgorithms)
+NS_IMPL_RELEASE_INHERITED(ZstdDecompressionStreamAlgorithms,
+ DecompressionStreamAlgorithms)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ZstdDecompressionStreamAlgorithms)
+NS_INTERFACE_MAP_END_INHERITING(DecompressionStreamAlgorithms)
+
+Result<already_AddRefed<ZstdDecompressionStreamAlgorithms>, nsresult>
+ZstdDecompressionStreamAlgorithms::Create() {
+ RefPtr<ZstdDecompressionStreamAlgorithms> alg =
+ new ZstdDecompressionStreamAlgorithms();
+ MOZ_TRY(alg->Init());
+ return alg.forget();
+}
+
+[[nodiscard]] nsresult ZstdDecompressionStreamAlgorithms::Init() {
+ mDStream = ZSTD_createDStream();
+ if (!mDStream) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ // Refuse any frame requiring larger than (1 << WINDOW_LOG_MAX) window size.
+ // Note: 1 << 23 == 8 * 1024 * 1024
+ static const uint8_t WINDOW_LOG_MAX = 23;
+ ZSTD_DCtx_setParameter(mDStream, ZSTD_d_windowLogMax, WINDOW_LOG_MAX);
+
+ return NS_OK;
+}
+
+// Shared by:
+// https://wicg.github.io/compression/#decompress-and-enqueue-a-chunk
+// https://wicg.github.io/compression/#decompress-flush-and-enqueue
+// All data errors throw TypeError by step 2: If this results in an error,
+// then throw a TypeError.
+MOZ_CAN_RUN_SCRIPT void ZstdDecompressionStreamAlgorithms::DecompressAndEnqueue(
+ JSContext* aCx, Span<const uint8_t> aInput, Flush aFlush,
+ TransformStreamDefaultController& aController, ErrorResult& aRv) {
+ MOZ_ASSERT_IF(aFlush == Flush::Yes, !aInput.Length());
+
+ if (mObservedStreamEnd && aInput.Length() > 0) {
+ aRv.ThrowTypeError("Unexpected input after the end of stream");
+ return;
+ }
+
+ ZSTD_inBuffer inBuffer = {/* src */ const_cast<uint8_t*>(aInput.Elements()),
+ /* size */ aInput.Length(),
+ /* pos */ 0};
+
+ JS::RootedVector<JSObject*> array(aCx);
+
+ while (inBuffer.pos < inBuffer.size && !mObservedStreamEnd) {
+ UniquePtr<uint8_t[], JS::FreePolicy> buffer(
+ static_cast<uint8_t*>(JS_malloc(aCx, kBufferSize)));
+ if (!buffer) {
+ aRv.ThrowTypeError("Out of memory");
+ return;
+ }
+
+ ZSTD_outBuffer outBuffer = {/* dst */ buffer.get(),
+ /* size */ kBufferSize,
+ /* pos */ 0};
+
+ size_t rv = ZSTD_decompressStream(mDStream, &outBuffer, &inBuffer);
+ if (ZSTD_isError(rv)) {
+ aRv.ThrowTypeError("zstd decompression error: "_ns +
+ nsDependentCString(ZSTD_getErrorName(rv)));
+ return;
+ }
+
+ if (rv == 0) {
+ mObservedStreamEnd = true;
+ }
+
+ // Step 3: If buffer is empty, return.
+ // (We'll implicitly return when the array is empty.)
+
+ // Step 4: Split buffer into one or more non-empty pieces and convert them
+ // into Uint8Arrays.
+ // (The buffer is 'split' by having a fixed sized buffer above.)
+
+ size_t written = outBuffer.pos;
+ if (written > 0) {
+ JS::Rooted<JSObject*> view(aCx, nsJSUtils::MoveBufferAsUint8Array(
+ aCx, written, std::move(buffer)));
+ if (!view || !array.append(view)) {
+ JS_ClearPendingException(aCx);
+ aRv.ThrowTypeError("Out of memory");
+ return;
+ }
+ }
+ }
+
+ // Step 5: For each Uint8Array array, enqueue array in ds's transform.
+ for (const auto& view : array) {
+ JS::Rooted<JS::Value> value(aCx, JS::ObjectValue(*view));
+ aController.Enqueue(aCx, value, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+
+ // Step 6: If the end of the compressed input has been reached, and ds's
+ // context has not fully consumed chunk, then throw a TypeError.
+ if (mObservedStreamEnd && inBuffer.pos < inBuffer.size) {
+ aRv.ThrowTypeError("Unexpected input after the end of stream");
+ return;
+ }
+
+ // Step 3 of
+ // https://wicg.github.io/compression/#decompress-flush-and-enqueue
+ // If the end of the compressed input has not been reached, then throw a
+ // TypeError.
+ if (aFlush == Flush::Yes && !mObservedStreamEnd) {
+ aRv.ThrowTypeError("The input is ended without reaching the stream end");
+ return;
+ }
+}
+
+ZstdDecompressionStreamAlgorithms::~ZstdDecompressionStreamAlgorithms() {
+ if (mDStream) {
+ ZSTD_freeDStream(mDStream);
+ mDStream = nullptr;
+ }
+}
+
+} // namespace mozilla::dom::compression
diff --git a/dom/compression/FormatZstd.h b/dom/compression/FormatZstd.h
@@ -0,0 +1,49 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_COMPRESSION_FORMATZSTD_H_
+#define DOM_COMPRESSION_FORMATZSTD_H_
+
+#include "BaseAlgorithms.h"
+
+struct ZSTD_DCtx_s;
+
+// See the zstd manual in https://facebook.github.io/zstd/zstd_manual.html or in
+// https://searchfox.org/mozilla-central/source/third_party/zstd/lib/zstd.h
+
+namespace mozilla::dom::compression {
+
+class ZstdDecompressionStreamAlgorithms : public DecompressionStreamAlgorithms {
+ public:
+ NS_DECL_ISUPPORTS_INHERITED
+ NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ZstdDecompressionStreamAlgorithms,
+ DecompressionStreamAlgorithms)
+
+ static Result<already_AddRefed<ZstdDecompressionStreamAlgorithms>, nsresult>
+ Create();
+
+ private:
+ ZstdDecompressionStreamAlgorithms() = default;
+
+ [[nodiscard]] nsresult Init();
+
+ // Shared by:
+ // https://wicg.github.io/compression/#decompress-and-enqueue-a-chunk
+ // https://wicg.github.io/compression/#decompress-flush-and-enqueue
+ // All data errors throw TypeError by step 2: If this results in an error,
+ // then throw a TypeError.
+ MOZ_CAN_RUN_SCRIPT void DecompressAndEnqueue(
+ JSContext* aCx, Span<const uint8_t> aInput, Flush aFlush,
+ TransformStreamDefaultController& aController, ErrorResult& aRv) override;
+
+ ~ZstdDecompressionStreamAlgorithms() override;
+
+ ZSTD_DCtx_s* mDStream = nullptr;
+ bool mObservedStreamEnd = false;
+};
+} // namespace mozilla::dom::compression
+
+#endif // DOM_COMPRESSION_FORMATZSTD_H_
diff --git a/dom/compression/moz.build b/dom/compression/moz.build
@@ -17,6 +17,7 @@ UNIFIED_SOURCES += [
"CompressionStream.cpp",
"DecompressionStream.cpp",
"FormatZlib.cpp",
+ "FormatZstd.cpp",
]
FINAL_LIBRARY = "xul"
