Add storage (serialization/deserialization) module

PiperOrigin-RevId: 716350769

MODULE.bazel

@@ -66,19 +66,20 @@ git_repository(
     remote = "https://github.com/google/ink-stroke-modeler.git",
 )
 
-bazel_dep(name = "rules_android", version = "0.6.0")
-bazel_dep(
-    name = "rules_jni",
-    version = "0.10.1",
-)
-
 git_repository(
     name = "libtess2",
     build_file = "third_party/libtess2/BUILD.bazel",
     commit = "fc52516467dfa124bdd967c15c7cf9faf02a34ca",
     remote = "https://github.com/memononen/libtess2.git",
 )
 
+bazel_dep(name = "protobuf", version = "29.3")
+bazel_dep(name = "rules_android", version = "0.6.0")
+bazel_dep(
+    name = "rules_jni",
+    version = "0.10.1",
+)
+
 SKIA_COMMIT = "515a23f3cbe1e2f54ffa6821e6da6f4891763f47"
 
 http_archive(

ink/jni/BUILD.bazel

@@ -1,4 +1,4 @@
-# Copyright 2024 Google LLC
+# Copyright 2024-2025 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -32,6 +32,7 @@ cc_binary(
         "//ink/color/internal/jni:native",
         "//ink/geometry/internal/jni:native",
         "//ink/rendering/skia/common_internal/jni:native",
+        "//ink/storage/internal/jni:native",
         "//ink/strokes/internal/jni:native",
     ],
 )

ink/jni/internal/BUILD.bazel

@@ -50,3 +50,21 @@ cc_library(
         ],
     }),
 )
+
+cc_library(
+    name = "jni_proto_util",
+    srcs = ["jni_proto_util.cc"],
+    hdrs = ["jni_proto_util.h"],
+    deps = [
+        "@com_google_absl//absl/base:core_headers",
+        "@com_google_absl//absl/log:absl_check",
+        "@com_google_absl//absl/status",
+        "@com_google_absl//absl/strings",
+        "@protobuf//:protobuf_lite",
+    ] + select({
+        "@platforms//os:android": [],
+        "//conditions:default": [
+            "@rules_jni//jni",
+        ],
+    }),
+)

ink/jni/internal/jni_proto_util.cc

@@ -0,0 +1,80 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "ink/jni/internal/jni_proto_util.h"
+
+#include <jni.h>
+
+#include <cstddef>
+
+#include "absl/log/absl_check.h"
+#include "absl/status/status.h"
+#include "absl/strings/str_cat.h"
+#include "google/protobuf/message_lite.h"
+
+namespace ink {
+namespace jni {
+
+absl::Status ParseProto(JNIEnv* env, jbyteArray serialized_proto,
+                        google::protobuf::MessageLite& dest) {
+  return ParseProto(env, serialized_proto, 0,
+                    env->GetArrayLength(serialized_proto), dest);
+}
+
+absl::Status ParseProto(JNIEnv* env, jbyteArray serialized_proto, jint offset,
+                        jint size, google::protobuf::MessageLite& dest) {
+  // TODO(b/290213178): See how often this copies using the isCopy pointer
+  //   argument, and consider using critical arrays to minimize copying.
+  jbyte* bytes = env->GetByteArrayElements(serialized_proto, nullptr);
+  ABSL_CHECK(bytes);
+  bool success = dest.ParseFromArray(bytes + offset, size);
+  env->ReleaseByteArrayElements(serialized_proto, bytes, 0);
+  if (!success) {
+    return absl::InvalidArgumentError(absl::StrCat(
+        "Failed to parse ", dest.GetTypeName(), " proto from byte[]."));
+  }
+  return absl::OkStatus();
+}
+
+absl::Status ParseProtoFromBuffer(JNIEnv* env,
+                                  jobject serialized_proto_direct_buffer,
+                                  jint offset, jint size,
+                                  google::protobuf::MessageLite& dest) {
+  void* addr = env->GetDirectBufferAddress(serialized_proto_direct_buffer);
+  ABSL_CHECK(addr);
+  // Cannot do arithmetic on void* due to unknown size of elements, so
+  // explicitly cast to clarify that the offset (and size) are in bytes.
+  jbyte* bytes = static_cast<jbyte*>(addr);
+  bool success = dest.ParseFromArray(bytes + offset, size);
+  if (!success) {
+    return absl::InvalidArgumentError(absl::StrCat(
+        "Failed to parse ", dest.GetTypeName(), " proto from direct buffer."));
+  }
+  return absl::OkStatus();
+}
+
+jbyteArray SerializeProto(JNIEnv* env, const google::protobuf::MessageLite& src) {
+  size_t size = src.ByteSizeLong();
+  jbyteArray serialized_proto = env->NewByteArray(size);
+  ABSL_CHECK(serialized_proto);
+  jbyte* bytes = env->GetByteArrayElements(serialized_proto, nullptr);
+  ABSL_CHECK(bytes);
+  bool success = src.SerializeToArray(bytes, size);
+  env->ReleaseByteArrayElements(serialized_proto, bytes, 0);
+  ABSL_CHECK(success);
+  return serialized_proto;
+}
+
+}  // namespace jni
+}  // namespace ink

ink/jni/internal/jni_proto_util.h

@@ -0,0 +1,56 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef INK_JNI_INTERNAL_JNI_PROTO_UTIL_H_
+#define INK_JNI_INTERNAL_JNI_PROTO_UTIL_H_
+
+#include <jni.h>
+
+#include "absl/status/status.h"
+#include "google/protobuf/message_lite.h"
+
+namespace ink {
+namespace jni {
+
+// Attempts to parse a serialized proto. If the proto doesn't parse, returns
+// a non-OK absl::Status.
+[[nodiscard]] absl::Status ParseProto(JNIEnv* env, jbyteArray serialized_proto,
+                                      google::protobuf::MessageLite& dest);
+
+// Attempts to parse a serialized proto. If the proto doesn't parse, returns
+// a non-OK absl::Status. `offset` is the starting point of the data within the
+// `serialized_proto` array, and `size` is how far beyond `offset` the data
+// continues.
+[[nodiscard]] absl::Status ParseProto(JNIEnv* env, jbyteArray serialized_proto,
+                                      jint offset, jint size,
+                                      google::protobuf::MessageLite& dest);
+
+// Attempts to parse a serialized proto from a direct java.nio.ByteBuffer. If
+// the proto doesn't parse, returns a non-OK absl::Status. `offset` is the
+// starting point of the data within the `serialized_proto` array, and `size`
+// is how far beyond `offset` the data continues.
+// Note: This has a different name than `ParseProto`, as jbyteArray is a type of
+// jobject so the two definitions would clash rather than serve as overloads.
+[[nodiscard]] absl::Status ParseProtoFromBuffer(
+    JNIEnv* env, jobject serialized_proto_direct_buffer, jint offset, jint size,
+    google::protobuf::MessageLite& dest);
+
+// Serializes a proto into a newly-allocated Java byte array.
+[[nodiscard]] jbyteArray SerializeProto(JNIEnv* env,
+                                        const google::protobuf::MessageLite& src);
+
+}  // namespace jni
+}  // namespace ink
+
+#endif  // INK_JNI_INTERNAL_JNI_PROTO_UTIL_H_