upb: create upb/dart/ for Dart FFI code written in C

PiperOrigin-RevId: 594483803

google3/third_party/upb/dart/BUILD

@@ -0,0 +1,41 @@
+# Copyright (c) 2009-2021, Google LLC
+# All rights reserved.
+#
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+load("//bazel:build_defs.bzl", "UPB_DEFAULT_COPTS")
+
+# begin:google_only
+# package(default_applicable_licenses = ["//upb:license"])
+# end:google_only
+
+# This library contains the upb functions called by the Dart FFI runtime.
+cc_library(
+    name = "libupb",
+    srcs = [":libupb.so"],
+    linkstatic = 1,
+    visibility = ["//third_party/dart/pb_runtime:__pkg__"],
+)
+
+# Weirdly, the Dart ffigen tool needs a cc_binary() target, not a cc_library().
+cc_binary(
+    name = "libupb.so",
+    srcs = ["upb_so.c"],
+    copts = UPB_DEFAULT_COPTS,
+    linkshared = 1,
+    linkstatic = 1,
+    visibility = ["//third_party/dart/pb_runtime:__pkg__"],
+    deps = [
+        "//upb:mem",
+        "//upb:message",
+        "//upb:message_accessors",
+        "//upb:message_compare",
+        "//upb:message_split64",
+        "//upb:mini_descriptor",
+        "//upb:mini_table",
+        "//upb:port",
+        "//upb:wire",
+    ],
+)

google3/third_party/upb/dart/upb_so.c

@@ -0,0 +1,21 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2023 Google LLC.  All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+// These headers form a spanning tree for the upb defs needed by the Dart FFI.
+
+#define UPB_BUILD_API
+
+// IWYU pragma: begin_exports
+#include "third_party/upb/upb/message/accessors_split64.h"
+#include "third_party/upb/upb/message/array_split64.h"
+#include "third_party/upb/upb/message/compare.h"
+#include "third_party/upb/upb/message/map.h"
+#include "third_party/upb/upb/message/message.h"
+#include "third_party/upb/upb/mini_descriptor/decode.h"
+#include "third_party/upb/upb/wire/decode.h"
+#include "third_party/upb/upb/wire/encode.h"
+// IWYU pragma: end_exports

upb/BUILD

@@ -312,28 +312,6 @@ alias(
     visibility = ["//visibility:public"],
 )
 
-# Internal C/C++ libraries #####################################################
-
-cc_binary(
-    name = "libupb.so",
-    srcs = ["upb_so.c"],
-    copts = UPB_DEFAULT_COPTS + ["-DUPB_BUILD_API"],
-    linkshared = 1,
-    linkstatic = 1,
-    visibility = ["//visibility:public"],
-    deps = [
-        ":mem",
-        ":message",
-        ":message_accessors",
-        ":message_compare",
-        ":message_split64",
-        ":mini_descriptor",
-        ":mini_table",
-        ":port",
-        ":wire",
-    ],
-)
-
 # Amalgamation #################################################################
 
 # begin:github_only