Provide a Ruby extension.

This adds a Ruby extension in ruby/ that is based on the 'upb' library
(now included as a submodule), and adds support for Ruby code generation
to the protoc compiler.

1 files changed, 313 insertions, 0 deletions

diff --git a/src/google/protobuf/compiler/ruby/ruby_generator.cc b/src/google/protobuf/compiler/ruby/ruby_generator.cc
new file mode 100644
index 00000000..82ccd72b
--- /dev/null
+++ b/src/google/protobuf/compiler/ruby/ruby_generator.cc
@@ -0,0 +1,313 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 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 <sstream>
+
+#include <google/protobuf/compiler/code_generator.h>
+#include <google/protobuf/compiler/plugin.h>
+#include <google/protobuf/descriptor.h>
+#include <google/protobuf/descriptor.pb.h>
+#include <google/protobuf/io/printer.h>
+#include <google/protobuf/io/zero_copy_stream.h>
+
+#include <google/protobuf/compiler/ruby/ruby_generator.h>
+
+using google::protobuf::internal::scoped_ptr;
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace ruby {
+
+// Forward decls.
+std::string IntToString(uint32_t value);
+std::string StripDotProto(const std::string& proto_file);
+std::string LabelForField(google::protobuf::FieldDescriptor* field);
+std::string TypeName(google::protobuf::FieldDescriptor* field);
+void GenerateMessage(const google::protobuf::Descriptor* message,
+                     google::protobuf::io::Printer* printer);
+void GenerateEnum(const google::protobuf::EnumDescriptor* en,
+                  google::protobuf::io::Printer* printer);
+void GenerateMessageAssignment(
+    const std::string& prefix,
+    const google::protobuf::Descriptor* message,
+    google::protobuf::io::Printer* printer);
+void GenerateEnumAssignment(
+    const std::string& prefix,
+    const google::protobuf::EnumDescriptor* en,
+    google::protobuf::io::Printer* printer);
+
+std::string IntToString(uint32_t value) {
+  std::ostringstream os;
+  os << value;
+  return os.str();
+}
+
+std::string StripDotProto(const std::string& proto_file) {
+  int lastindex = proto_file.find_last_of(".");
+  return proto_file.substr(0, lastindex);
+}
+
+std::string LabelForField(const google::protobuf::FieldDescriptor* field) {
+  switch (field->label()) {
+    case FieldDescriptor::LABEL_OPTIONAL: return "optional";
+    case FieldDescriptor::LABEL_REQUIRED: return "required";
+    case FieldDescriptor::LABEL_REPEATED: return "repeated";
+    default: assert(false); return "";
+  }
+}
+
+std::string TypeName(const google::protobuf::FieldDescriptor* field) {
+  switch (field->cpp_type()) {
+    case FieldDescriptor::CPPTYPE_INT32: return "int32";
+    case FieldDescriptor::CPPTYPE_INT64: return "int64";
+    case FieldDescriptor::CPPTYPE_UINT32: return "uint32";
+    case FieldDescriptor::CPPTYPE_UINT64: return "uint64";
+    case FieldDescriptor::CPPTYPE_DOUBLE: return "double";
+    case FieldDescriptor::CPPTYPE_FLOAT: return "float";
+    case FieldDescriptor::CPPTYPE_BOOL: return "bool";
+    case FieldDescriptor::CPPTYPE_ENUM: return "enum";
+    case FieldDescriptor::CPPTYPE_STRING: return "string";
+    case FieldDescriptor::CPPTYPE_MESSAGE: return "message";
+    default: assert(false); return "";
+  }
+}
+
+void GenerateMessage(const google::protobuf::Descriptor* message,
+                     google::protobuf::io::Printer* printer) {
+  printer->Print(
+    "add_message \"$name$\" do\n",
+    "name", message->full_name());
+  printer->Indent();
+
+  for (int i = 0; i < message->field_count(); i++) {
+    const FieldDescriptor* field = message->field(i);
+    printer->Print(
+      "$label$ :$name$, ",
+      "label", LabelForField(field),
+      "name", field->name());
+    printer->Print(
+      ":$type$, $number$",
+      "type", TypeName(field),
+      "number", IntToString(field->number()));
+    if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
+      printer->Print(
+        ", \"$subtype$\"\n",
+       "subtype", field->message_type()->full_name());
+    } else if (field->cpp_type() == FieldDescriptor::CPPTYPE_ENUM) {
+      printer->Print(
+        ", \"$subtype$\"\n",
+        "subtype", field->enum_type()->full_name());
+    } else {
+      printer->Print("\n");
+    }
+  }
+
+  printer->Outdent();
+  printer->Print("end\n");
+
+  for (int i = 0; i < message->nested_type_count(); i++) {
+    GenerateMessage(message->nested_type(i), printer);
+  }
+  for (int i = 0; i < message->enum_type_count(); i++) {
+    GenerateEnum(message->enum_type(i), printer);
+  }
+}
+
+void GenerateEnum(const google::protobuf::EnumDescriptor* en,
+                  google::protobuf::io::Printer* printer) {
+  printer->Print(
+    "add_enum \"$name$\" do\n",
+    "name", en->full_name());
+  printer->Indent();
+
+  for (int i = 0; i < en->value_count(); i++) {
+    const EnumValueDescriptor* value = en->value(i);
+    printer->Print(
+      "value :$name$, $number$\n",
+      "name", value->name(),
+      "number", IntToString(value->number()));
+  }
+
+  printer->Outdent();
+  printer->Print(
+    "end\n");
+}
+
+// Module names, class names, and enum value names need to be Ruby constants,
+// which must start with a capital letter.
+std::string RubifyConstant(const std::string& name) {
+  std::string ret = name;
+  if (!ret.empty()) {
+    if (ret[0] >= 'a' && ret[0] <= 'z') {
+      // If it starts with a lowercase letter, capitalize it.
+      ret[0] = ret[0] - 'a' + 'A';
+    } else if (ret[0] < 'A' || ret[0] > 'Z') {
+      // Otherwise (e.g. if it begins with an underscore), we need to come up
+      // with some prefix that starts with a capital letter. We could be smarter
+      // here, e.g. try to strip leading underscores, but this may cause other
+      // problems if the user really intended the name. So let's just prepend a
+      // well-known suffix.
+      ret = "PB_" + ret;
+    }
+  }
+  return ret;
+}
+
+void GenerateMessageAssignment(
+    const std::string& prefix,
+    const google::protobuf::Descriptor* message,
+    google::protobuf::io::Printer* printer) {
+  printer->Print(
+    "$prefix$$name$ = ",
+    "prefix", prefix,
+    "name", RubifyConstant(message->name()));
+  printer->Print(
+    "Google::Protobuf::DescriptorPool.generated_pool."
+    "lookup(\"$full_name$\").msgclass\n",
+    "full_name", message->full_name());
+
+  std::string nested_prefix = prefix + message->name() + "::";
+  for (int i = 0; i < message->nested_type_count(); i++) {
+    GenerateMessageAssignment(nested_prefix, message->nested_type(i), printer);
+  }
+  for (int i = 0; i < message->enum_type_count(); i++) {
+    GenerateEnumAssignment(nested_prefix, message->enum_type(i), printer);
+  }
+}
+
+void GenerateEnumAssignment(
+    const std::string& prefix,
+    const google::protobuf::EnumDescriptor* en,
+    google::protobuf::io::Printer* printer) {
+  printer->Print(
+    "$prefix$$name$ = ",
+    "prefix", prefix,
+    "name", RubifyConstant(en->name()));
+  printer->Print(
+    "Google::Protobuf::DescriptorPool.generated_pool."
+    "lookup(\"$full_name$\").enummodule\n",
+    "full_name", en->full_name());
+}
+
+int GeneratePackageModules(
+    std::string package_name,
+    google::protobuf::io::Printer* printer) {
+  int levels = 0;
+  while (!package_name.empty()) {
+    size_t dot_index = package_name.find(".");
+    string component;
+    if (dot_index == string::npos) {
+      component = package_name;
+      package_name = "";
+    } else {
+      component = package_name.substr(0, dot_index);
+      package_name = package_name.substr(dot_index + 1);
+    }
+    component = RubifyConstant(component);
+    printer->Print(
+      "module $name$\n",
+      "name", component);
+    printer->Indent();
+    levels++;
+  }
+  return levels;
+}
+
+void EndPackageModules(
+    int levels,
+    google::protobuf::io::Printer* printer) {
+  while (levels > 0) {
+    levels--;
+    printer->Outdent();
+    printer->Print(
+      "end\n");
+  }
+}
+
+void GenerateFile(const google::protobuf::FileDescriptor* file,
+                  google::protobuf::io::Printer* printer) {
+  printer->Print(
+    "# Generated by the protocol buffer compiler.  DO NOT EDIT!\n"
+    "# source: $filename$\n"
+    "\n",
+    "filename", file->name());
+
+  printer->Print(
+    "require 'protobuf'\n\n");
+
+  for (int i = 0; i < file->dependency_count(); i++) {
+    const std::string& name = file->dependency(i)->name();
+    printer->Print(
+      "require '$name$'\n", "name", StripDotProto(name));
+  }
+
+  printer->Print(
+    "Google::Protobuf::DescriptorPool.generated_pool.build do\n");
+  printer->Indent();
+  for (int i = 0; i < file->message_type_count(); i++) {
+    GenerateMessage(file->message_type(i), printer);
+  }
+  for (int i = 0; i < file->enum_type_count(); i++) {
+    GenerateEnum(file->enum_type(i), printer);
+  }
+  printer->Outdent();
+  printer->Print(
+    "end\n\n");
+
+  int levels = GeneratePackageModules(file->package(), printer);
+  for (int i = 0; i < file->message_type_count(); i++) {
+    GenerateMessageAssignment("", file->message_type(i), printer);
+  }
+  for (int i = 0; i < file->enum_type_count(); i++) {
+    GenerateEnumAssignment("", file->enum_type(i), printer);
+  }
+  EndPackageModules(levels, printer);
+}
+
+bool Generator::Generate(
+    const FileDescriptor* file,
+    const string& parameter,
+    GeneratorContext* generator_context,
+    string* error) const {
+  std::string filename =
+      StripDotProto(file->name()) + ".rb";
+  scoped_ptr<io::ZeroCopyOutputStream> output(generator_context->Open(filename));
+  io::Printer printer(output.get(), '$');
+
+  GenerateFile(file, &printer);
+
+  return true;
+}
+
+}  // namespace ruby
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google