Nano protobufs.

Like micro protobufs except:

- No setter/getter/hazzer functions.
- Has state is not available. Outputs all fields != their default.
- CodedInputStream can only take byte[] (not InputStream).
- Repeated fields are in arrays, not ArrayList or Vector.
- Unset messages/groups are null, not "defaultInstance()".
- Required fields are always serialized.

To use:

- Link libprotobuf-java-2.3.0-nano runtime.
- Use LOCAL_PROTOC_OPTIMIZE_TYPE := nano

Change-Id: I7429015b3c5f7f38b7be01eb2d4927f7a9999c80

1 files changed, 372 insertions, 0 deletions

diff --git a/src/google/protobuf/compiler/javanano/javanano_message.cc b/src/google/protobuf/compiler/javanano/javanano_message.cc
new file mode 100644
index 0000000..f8a4fe7
--- /dev/null
+++ b/src/google/protobuf/compiler/javanano/javanano_message.cc
@@ -0,0 +1,372 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// Author: kenton@google.com (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#include <algorithm>
+#include <google/protobuf/stubs/hash.h>
+#include <google/protobuf/compiler/javanano/javanano_message.h>
+#include <google/protobuf/compiler/javanano/javanano_enum.h>
+#include <google/protobuf/compiler/javanano/javanano_helpers.h>
+#include <google/protobuf/stubs/strutil.h>
+#include <google/protobuf/io/printer.h>
+#include <google/protobuf/io/coded_stream.h>
+#include <google/protobuf/wire_format.h>
+#include <google/protobuf/descriptor.pb.h>
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace javanano {
+
+using internal::WireFormat;
+using internal::WireFormatLite;
+
+namespace {
+
+void PrintFieldComment(io::Printer* printer, const FieldDescriptor* field) {
+  // Print the field's proto-syntax definition as a comment.  We don't want to
+  // print group bodies so we cut off after the first line.
+  string def = field->DebugString();
+  printer->Print("// $def$\n",
+    "def", def.substr(0, def.find_first_of('\n')));
+}
+
+struct FieldOrderingByNumber {
+  inline bool operator()(const FieldDescriptor* a,
+                         const FieldDescriptor* b) const {
+    return a->number() < b->number();
+  }
+};
+
+// Sort the fields of the given Descriptor by number into a new[]'d array
+// and return it.
+const FieldDescriptor** SortFieldsByNumber(const Descriptor* descriptor) {
+  const FieldDescriptor** fields =
+    new const FieldDescriptor*[descriptor->field_count()];
+  for (int i = 0; i < descriptor->field_count(); i++) {
+    fields[i] = descriptor->field(i);
+  }
+  sort(fields, fields + descriptor->field_count(),
+       FieldOrderingByNumber());
+  return fields;
+}
+
+// Get an identifier that uniquely identifies this type within the file.
+// This is used to declare static variables related to this type at the
+// outermost file scope.
+string UniqueFileScopeIdentifier(const Descriptor* descriptor) {
+  return "static_" + StringReplace(descriptor->full_name(), ".", "_", true);
+}
+
+}  // namespace
+
+// ===================================================================
+
+MessageGenerator::MessageGenerator(const Descriptor* descriptor, const Params& params)
+  : params_(params),
+    descriptor_(descriptor),
+    field_generators_(descriptor, params) {
+}
+
+MessageGenerator::~MessageGenerator() {}
+
+void MessageGenerator::GenerateStaticVariables(io::Printer* printer) {
+  // Generate static members for all nested types.
+  for (int i = 0; i < descriptor_->nested_type_count(); i++) {
+    // TODO(kenton):  Reuse MessageGenerator objects?
+    MessageGenerator(descriptor_->nested_type(i), params_)
+      .GenerateStaticVariables(printer);
+  }
+}
+
+void MessageGenerator::GenerateStaticVariableInitializers(
+    io::Printer* printer) {
+  // Generate static member initializers for all nested types.
+  for (int i = 0; i < descriptor_->nested_type_count(); i++) {
+    // TODO(kenton):  Reuse MessageGenerator objects?
+    MessageGenerator(descriptor_->nested_type(i), params_)
+      .GenerateStaticVariableInitializers(printer);
+  }
+
+  if (descriptor_->extension_count() != 0) {
+    GOOGLE_LOG(FATAL) << "Extensions not supported in NANO_RUNTIME\n";
+  }
+}
+
+void MessageGenerator::Generate(io::Printer* printer) {
+  bool is_own_file =
+    params_.java_multiple_files() || ((descriptor_->containing_type() == NULL)
+        && !params_.has_java_outer_classname(descriptor_->file()->name()));
+
+#if 0
+  GOOGLE_LOG(INFO) << "is_own_file=" << is_own_file;
+  GOOGLE_LOG(INFO) << "containing_type()=" << ((descriptor_->containing_type() == NULL) ? "NULL" : "not null");
+  GOOGLE_LOG(INFO) << "java_multiple_files()=" << params_.java_multiple_files();
+  GOOGLE_LOG(INFO) << "has_java_outer_classname()=" << params_.has_java_outer_classname(file_->name());
+#endif
+
+  if ((descriptor_->extension_count() != 0)
+      || (descriptor_->extension_range_count() != 0)) {
+    GOOGLE_LOG(FATAL) << "Extensions not supported in NANO_RUNTIME\n";
+  }
+
+  // Note: Fields (which will be emitted in the loop, below) may have the same names as fields in
+  // the inner or outer class.  This causes Java warnings, but is not fatal, so we suppress those
+  // warnings here in the class declaration.
+  printer->Print(
+    "@SuppressWarnings(\"hiding\")\n"
+    "public $modifiers$ final class $classname$ extends\n"
+    "    com.google.protobuf.nano.MessageNano {\n",
+    "modifiers", is_own_file ? "" : "static",
+    "classname", descriptor_->name());
+  printer->Indent();
+  printer->Print(
+    "public static final $classname$ EMPTY_ARRAY[] = {};\n"
+    "public $classname$() {}\n"
+    "\n",
+    "classname", descriptor_->name());
+
+  // Nested types and extensions
+  for (int i = 0; i < descriptor_->enum_type_count(); i++) {
+    EnumGenerator(descriptor_->enum_type(i), params_).Generate(printer);
+  }
+
+  for (int i = 0; i < descriptor_->nested_type_count(); i++) {
+    MessageGenerator(descriptor_->nested_type(i), params_).Generate(printer);
+  }
+
+  // Fields
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    PrintFieldComment(printer, descriptor_->field(i));
+    field_generators_.get(descriptor_->field(i)).GenerateMembers(printer);
+    printer->Print("\n");
+  }
+
+  GenerateClear(printer);
+  GenerateMessageSerializationMethods(printer);
+  GenerateMergeFromMethods(printer);
+  GenerateParseFromMethods(printer);
+
+  printer->Outdent();
+  printer->Print("}\n\n");
+}
+
+// ===================================================================
+
+void MessageGenerator::
+GenerateMessageSerializationMethods(io::Printer* printer) {
+  scoped_array<const FieldDescriptor*> sorted_fields(
+    SortFieldsByNumber(descriptor_));
+
+  if (descriptor_->extension_range_count() != 0) {
+    GOOGLE_LOG(FATAL) << "Extensions not supported in NANO_RUNTIME\n";
+  }
+
+  // writeTo only throws an exception if it contains one or more fields to write
+  if (descriptor_->field_count() > 0) {
+    printer->Print(
+      "@Override\n"
+      "public void writeTo(com.google.protobuf.nano.CodedOutputByteBufferNano output)\n"
+      "                    throws java.io.IOException {\n");
+  } else {
+    printer->Print(
+      "@Override\n"
+      "public void writeTo(com.google.protobuf.nano.CodedOutputByteBufferNano output) {\n");
+  }
+  printer->Indent();
+
+  // Output the fields in sorted order
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+      GenerateSerializeOneField(printer, sorted_fields[i]);
+  }
+
+  printer->Outdent();
+  printer->Print(
+    "}\n"
+    "\n"
+    "private int cachedSize = -1;\n"
+    "@Override\n"
+    "public int getCachedSize() {\n"
+    "  if (cachedSize < 0) {\n"
+    "    // getSerializedSize sets cachedSize\n"
+    "    getSerializedSize();\n"
+    "  }\n"
+    "  return cachedSize;\n"
+    "}\n"
+    "\n"
+    "@Override\n"
+    "public int getSerializedSize() {\n"
+    "  int size = 0;\n");
+  printer->Indent();
+
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    field_generators_.get(sorted_fields[i]).GenerateSerializedSizeCode(printer);
+  }
+
+  printer->Outdent();
+  printer->Print(
+    "  cachedSize = size;\n"
+    "  return size;\n"
+    "}\n"
+    "\n");
+}
+
+void MessageGenerator::GenerateMergeFromMethods(io::Printer* printer) {
+  scoped_array<const FieldDescriptor*> sorted_fields(
+    SortFieldsByNumber(descriptor_));
+
+  printer->Print(
+    "@Override\n"
+    "public $classname$ mergeFrom(\n"
+    "    com.google.protobuf.nano.CodedInputByteBufferNano input)\n"
+    "    throws java.io.IOException {\n",
+    "classname", descriptor_->name());
+
+  printer->Indent();
+
+  printer->Print(
+    "while (true) {\n");
+  printer->Indent();
+
+  printer->Print(
+    "int tag = input.readTag();\n"
+    "switch (tag) {\n");
+  printer->Indent();
+
+  printer->Print(
+    "case 0:\n"          // zero signals EOF / limit reached
+    "  return this;\n"
+    "default: {\n"
+    "  if (!com.google.protobuf.nano.WireFormatNano.parseUnknownField(input, tag)) {\n"
+    "    return this;\n"   // it's an endgroup tag
+    "  }\n"
+    "  break;\n"
+    "}\n");
+
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    const FieldDescriptor* field = sorted_fields[i];
+    uint32 tag = WireFormatLite::MakeTag(field->number(),
+      WireFormat::WireTypeForField(field));
+
+    printer->Print(
+      "case $tag$: {\n",
+      "tag", SimpleItoa(tag));
+    printer->Indent();
+
+    field_generators_.get(field).GenerateParsingCode(printer);
+
+    printer->Outdent();
+    printer->Print(
+      "  break;\n"
+      "}\n");
+  }
+
+  printer->Outdent();
+  printer->Outdent();
+  printer->Outdent();
+  printer->Print(
+    "    }\n"     // switch (tag)
+    "  }\n"       // while (true)
+    "}\n"
+    "\n");
+}
+
+void MessageGenerator::
+GenerateParseFromMethods(io::Printer* printer) {
+  bool is_own_file =
+    descriptor_->containing_type() == NULL;
+
+  // Note:  These are separate from GenerateMessageSerializationMethods()
+  //   because they need to be generated even for messages that are optimized
+  //   for code size.
+  printer->Print(
+    "public $static$ $classname$ parseFrom(byte[] data)\n"
+    "    throws com.google.protobuf.nano.InvalidProtocolBufferNanoException {\n"
+    "  return ($classname$) com.google.protobuf.nano.MessageNano.mergeFrom(new $classname$(), data);\n"
+    "}\n"
+    "\n"
+    "public $static$ $classname$ parseFrom(\n"
+    "        com.google.protobuf.nano.CodedInputByteBufferNano input)\n"
+    "    throws java.io.IOException {\n"
+    "  return new $classname$().mergeFrom(input);\n"
+    "}\n"
+    "\n",
+    "static", (is_own_file ? "static" : ""),
+    "classname", descriptor_->name());
+}
+
+void MessageGenerator::GenerateSerializeOneField(
+    io::Printer* printer, const FieldDescriptor* field) {
+  field_generators_.get(field).GenerateSerializationCode(printer);
+}
+
+void MessageGenerator::GenerateClear(io::Printer* printer) {
+  printer->Print(
+    "public final $classname$ clear() {\n",
+    "classname", descriptor_->name());
+  printer->Indent();
+
+  // Call clear for all of the fields.
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    const FieldDescriptor* field = descriptor_->field(i);
+
+    if (field->type() == FieldDescriptor::TYPE_BYTES &&
+        !field->default_value_string().empty()) {
+      // Need to clone the default value because it is of a mutable
+      // type.
+      printer->Print(
+        "$name$ = $default$.clone();\n",
+        "name", UnderscoresToCamelCase(field),
+        "default", DefaultValue(params_, field));
+    } else {
+      printer->Print(
+        "$name$ = $default$;\n",
+        "name", UnderscoresToCamelCase(field),
+        "default", DefaultValue(params_, field));
+    }
+  }
+
+  printer->Outdent();
+  printer->Print(
+    "  cachedSize = -1;\n"
+    "  return this;\n"
+    "}\n"
+    "\n");
+}
+
+// ===================================================================
+
+}  // namespace javanano
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google