Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/ruby/ext/google/protobuf_c/protobuf.c

-// Protocol Buffers - Google's data interchange format
-// Copyright 2014 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "protobuf.h"
-
-// -----------------------------------------------------------------------------
-// Global map from upb {msg,enum}defs to wrapper Descriptor/EnumDescriptor
-// instances.
-// -----------------------------------------------------------------------------
-
-// This is a hash table from def objects (encoded by converting pointers to
-// Ruby integers) to MessageDef/EnumDef instances (as Ruby values).
-VALUE upb_def_to_ruby_obj_map;
-
-VALUE cError;
-VALUE cParseError;
-
-void add_def_obj(const void* def, VALUE value) {
-  rb_hash_aset(upb_def_to_ruby_obj_map, ULL2NUM((intptr_t)def), value);
-}
-
-VALUE get_def_obj(const void* def) {
-  return rb_hash_aref(upb_def_to_ruby_obj_map, ULL2NUM((intptr_t)def));
-}
-
-// -----------------------------------------------------------------------------
-// Utilities.
-// -----------------------------------------------------------------------------
-
-// Raises a Ruby error if |status| is not OK, using its error message.
-void check_upb_status(const upb_status* status, const char* msg) {
-  if (!upb_ok(status)) {
-    rb_raise(rb_eRuntimeError, "%s: %s\n", msg, upb_status_errmsg(status));
-  }
-}
-
-// String encodings: we look these up once, at load time, and then cache them
-// here.
-rb_encoding* kRubyStringUtf8Encoding;
-rb_encoding* kRubyStringASCIIEncoding;
-rb_encoding* kRubyString8bitEncoding;
-
-// Ruby-interned string: "descriptor". We use this identifier to store an
-// instance variable on message classes we create in order to link them back to
-// their descriptors.
-//
-// We intern this once at module load time then use the interned identifier at
-// runtime in order to avoid the cost of repeatedly interning in hot paths.
-const char* kDescriptorInstanceVar = "descriptor";
-ID descriptor_instancevar_interned;
-
-// -----------------------------------------------------------------------------
-// Initialization/entry point.
-// -----------------------------------------------------------------------------
-
-// This must be named "Init_protobuf_c" because the Ruby module is named
-// "protobuf_c" -- the VM looks for this symbol in our .so.
-void Init_protobuf_c() {
-  descriptor_instancevar_interned = rb_intern(kDescriptorInstanceVar);
-  VALUE google = rb_define_module("Google");
-  VALUE protobuf = rb_define_module_under(google, "Protobuf");
-  VALUE internal = rb_define_module_under(protobuf, "Internal");
-  DescriptorPool_register(protobuf);
-  Descriptor_register(protobuf);
-  FieldDescriptor_register(protobuf);
-  OneofDescriptor_register(protobuf);
-  EnumDescriptor_register(protobuf);
-  MessageBuilderContext_register(internal);
-  OneofBuilderContext_register(internal);
-  EnumBuilderContext_register(internal);
-  Builder_register(internal);
-  RepeatedField_register(protobuf);
-  Map_register(protobuf);
-
-  cError = rb_const_get(protobuf, rb_intern("Error"));
-  cParseError = rb_const_get(protobuf, rb_intern("ParseError"));
-
-  rb_define_singleton_method(protobuf, "deep_copy",
-                             Google_Protobuf_deep_copy, 1);
-
-  kRubyStringUtf8Encoding = rb_utf8_encoding();
-  kRubyStringASCIIEncoding = rb_usascii_encoding();
-  kRubyString8bitEncoding = rb_ascii8bit_encoding();
-
-  upb_def_to_ruby_obj_map = rb_hash_new();
-  rb_gc_register_address(&upb_def_to_ruby_obj_map);
-}