src/third_party/protobuf/src/google/protobuf/compiler/cpp/cpp_service.cc

   1 // Protocol Buffers - Google's data interchange format
   2 // Copyright 2008 Google Inc.  All rights reserved.
   3 // http://code.google.com/p/protobuf/
   4 //
   5 // Redistribution and use in source and binary forms, with or without
   6 // modification, are permitted provided that the following conditions are
   7 // met:
   8 //
   9 //     * Redistributions of source code must retain the above copyright
  10 // notice, this list of conditions and the following disclaimer.
  11 //     * Redistributions in binary form must reproduce the above
  12 // copyright notice, this list of conditions and the following disclaimer
  13 // in the documentation and/or other materials provided with the
  14 // distribution.
  15 //     * Neither the name of Google Inc. nor the names of its
  16 // contributors may be used to endorse or promote products derived from
  17 // this software without specific prior written permission.
  18 //
  19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30
  31 // Author: kenton@google.com (Kenton Varda)
  32 //  Based on original Protocol Buffers design by
  33 //  Sanjay Ghemawat, Jeff Dean, and others.
  34
  35 #include <google/protobuf/compiler/cpp/cpp_service.h>
  36 #include <google/protobuf/compiler/cpp/cpp_helpers.h>
  37 #include <google/protobuf/io/printer.h>
  38 #include <google/protobuf/stubs/strutil.h>
  39
  40 namespace google {
  41 namespace protobuf {
  42 namespace compiler {
  43 namespace cpp {
  44
  45 ServiceGenerator::ServiceGenerator(const ServiceDescriptor* descriptor,
  46                                    const Options& options)
  47   : descriptor_(descriptor) {
  48   vars_["classname"] = descriptor_->name();
  49   vars_["full_name"] = descriptor_->full_name();
  50   if (options.dllexport_decl.empty()) {
  51     vars_["dllexport"] = "";
  52   } else {
  53     vars_["dllexport"] = options.dllexport_decl + " ";
  54   }
  55 }
  56
  57 ServiceGenerator::~ServiceGenerator() {}
  58
  59 void ServiceGenerator::GenerateDeclarations(io::Printer* printer) {
  60   // Forward-declare the stub type.
  61   printer->Print(vars_,
  62     "class $classname$_Stub;\n"
  63     "\n");
  64
  65   GenerateInterface(printer);
  66   GenerateStubDefinition(printer);
  67 }
  68
  69 void ServiceGenerator::GenerateInterface(io::Printer* printer) {
  70   printer->Print(vars_,
  71     "class $dllexport$$classname$ : public ::google::protobuf::Service {\n"
  72     " protected:\n"
  73     "  // This class should be treated as an abstract interface.\n"
  74     "  inline $classname$() {};\n"
  75     " public:\n"
  76     "  virtual ~$classname$();\n");
  77   printer->Indent();
  78
  79   printer->Print(vars_,
  80     "\n"
  81     "typedef $classname$_Stub Stub;\n"
  82     "\n"
  83     "static const ::google::protobuf::ServiceDescriptor* descriptor();\n"
  84     "\n");
  85
  86   GenerateMethodSignatures(VIRTUAL, printer);
  87
  88   printer->Print(
  89     "\n"
  90     "// implements Service ----------------------------------------------\n"
  91     "\n"
  92     "const ::google::protobuf::ServiceDescriptor* GetDescriptor();\n"
  93     "void CallMethod(const ::google::protobuf::MethodDescriptor* method,\n"
  94     "                ::google::protobuf::RpcController* controller,\n"
  95     "                const ::google::protobuf::Message* request,\n"
  96     "                ::google::protobuf::Message* response,\n"
  97     "                ::google::protobuf::Closure* done);\n"
  98     "const ::google::protobuf::Message& GetRequestPrototype(\n"
  99     "  const ::google::protobuf::MethodDescriptor* method) const;\n"
 100     "const ::google::protobuf::Message& GetResponsePrototype(\n"
 101     "  const ::google::protobuf::MethodDescriptor* method) const;\n");
 102
 103   printer->Outdent();
 104   printer->Print(vars_,
 105     "\n"
 106     " private:\n"
 107     "  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS($classname$);\n"
 108     "};\n"
 109     "\n");
 110 }
 111
 112 void ServiceGenerator::GenerateStubDefinition(io::Printer* printer) {
 113   printer->Print(vars_,
 114     "class $dllexport$$classname$_Stub : public $classname$ {\n"
 115     " public:\n");
 116
 117   printer->Indent();
 118
 119   printer->Print(vars_,
 120     "$classname$_Stub(::google::protobuf::RpcChannel* channel);\n"
 121     "$classname$_Stub(::google::protobuf::RpcChannel* channel,\n"
 122     "                 ::google::protobuf::Service::ChannelOwnership ownership);\n"
 123     "~$classname$_Stub();\n"
 124     "\n"
 125     "inline ::google::protobuf::RpcChannel* channel() { return channel_; }\n"
 126     "\n"
 127     "// implements $classname$ ------------------------------------------\n"
 128     "\n");
 129
 130   GenerateMethodSignatures(NON_VIRTUAL, printer);
 131
 132   printer->Outdent();
 133   printer->Print(vars_,
 134     " private:\n"
 135     "  ::google::protobuf::RpcChannel* channel_;\n"
 136     "  bool owns_channel_;\n"
 137     "  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS($classname$_Stub);\n"
 138     "};\n"
 139     "\n");
 140 }
 141
 142 void ServiceGenerator::GenerateMethodSignatures(
 143     VirtualOrNon virtual_or_non, io::Printer* printer) {
 144   for (int i = 0; i < descriptor_->method_count(); i++) {
 145     const MethodDescriptor* method = descriptor_->method(i);
 146     map<string, string> sub_vars;
 147     sub_vars["name"] = method->name();
 148     sub_vars["input_type"] = ClassName(method->input_type(), true);
 149     sub_vars["output_type"] = ClassName(method->output_type(), true);
 150     sub_vars["virtual"] = virtual_or_non == VIRTUAL ? "virtual " : "";
 151
 152     printer->Print(sub_vars,
 153       "$virtual$void $name$(::google::protobuf::RpcController* controller,\n"
 154       "                     const $input_type$* request,\n"
 155       "                     $output_type$* response,\n"
 156       "                     ::google::protobuf::Closure* done);\n");
 157   }
 158 }
 159
 160 // ===================================================================
 161
 162 void ServiceGenerator::GenerateDescriptorInitializer(
 163     io::Printer* printer, int index) {
 164   map<string, string> vars;
 165   vars["classname"] = descriptor_->name();
 166   vars["index"] = SimpleItoa(index);
 167
 168   printer->Print(vars,
 169     "$classname$_descriptor_ = file->service($index$);\n");
 170 }
 171
 172 // ===================================================================
 173
 174 void ServiceGenerator::GenerateImplementation(io::Printer* printer) {
 175   printer->Print(vars_,
 176     "$classname$::~$classname$() {}\n"
 177     "\n"
 178     "const ::google::protobuf::ServiceDescriptor* $classname$::descriptor() {\n"
 179     "  protobuf_AssignDescriptorsOnce();\n"
 180     "  return $classname$_descriptor_;\n"
 181     "}\n"
 182     "\n"
 183     "const ::google::protobuf::ServiceDescriptor* $classname$::GetDescriptor() {\n"
 184     "  protobuf_AssignDescriptorsOnce();\n"
 185     "  return $classname$_descriptor_;\n"
 186     "}\n"
 187     "\n");
 188
 189   // Generate methods of the interface.
 190   GenerateNotImplementedMethods(printer);
 191   GenerateCallMethod(printer);
 192   GenerateGetPrototype(REQUEST, printer);
 193   GenerateGetPrototype(RESPONSE, printer);
 194
 195   // Generate stub implementation.
 196   printer->Print(vars_,
 197     "$classname$_Stub::$classname$_Stub(::google::protobuf::RpcChannel* channel)\n"
 198     "  : channel_(channel), owns_channel_(false) {}\n"
 199     "$classname$_Stub::$classname$_Stub(\n"
 200     "    ::google::protobuf::RpcChannel* channel,\n"
 201     "    ::google::protobuf::Service::ChannelOwnership ownership)\n"
 202     "  : channel_(channel),\n"
 203     "    owns_channel_(ownership == ::google::protobuf::Service::STUB_OWNS_CHANNEL) {}\n"
 204     "$classname$_Stub::~$classname$_Stub() {\n"
 205     "  if (owns_channel_) delete channel_;\n"
 206     "}\n"
 207     "\n");
 208
 209   GenerateStubMethods(printer);
 210 }
 211
 212 void ServiceGenerator::GenerateNotImplementedMethods(io::Printer* printer) {
 213   for (int i = 0; i < descriptor_->method_count(); i++) {
 214     const MethodDescriptor* method = descriptor_->method(i);
 215     map<string, string> sub_vars;
 216     sub_vars["classname"] = descriptor_->name();
 217     sub_vars["name"] = method->name();
 218     sub_vars["index"] = SimpleItoa(i);
 219     sub_vars["input_type"] = ClassName(method->input_type(), true);
 220     sub_vars["output_type"] = ClassName(method->output_type(), true);
 221
 222     printer->Print(sub_vars,
 223       "void $classname$::$name$(::google::protobuf::RpcController* controller,\n"
 224       "                         const $input_type$*,\n"
 225       "                         $output_type$*,\n"
 226       "                         ::google::protobuf::Closure* done) {\n"
 227       "  controller->SetFailed(\"Method $name$() not implemented.\");\n"
 228       "  done->Run();\n"
 229       "}\n"
 230       "\n");
 231   }
 232 }
 233
 234 void ServiceGenerator::GenerateCallMethod(io::Printer* printer) {
 235   printer->Print(vars_,
 236     "void $classname$::CallMethod(const ::google::protobuf::MethodDescriptor* method,\n"
 237     "                             ::google::protobuf::RpcController* controller,\n"
 238     "                             const ::google::protobuf::Message* request,\n"
 239     "                             ::google::protobuf::Message* response,\n"
 240     "                             ::google::protobuf::Closure* done) {\n"
 241     "  GOOGLE_DCHECK_EQ(method->service(), $classname$_descriptor_);\n"
 242     "  switch(method->index()) {\n");
 243
 244   for (int i = 0; i < descriptor_->method_count(); i++) {
 245     const MethodDescriptor* method = descriptor_->method(i);
 246     map<string, string> sub_vars;
 247     sub_vars["name"] = method->name();
 248     sub_vars["index"] = SimpleItoa(i);
 249     sub_vars["input_type"] = ClassName(method->input_type(), true);
 250     sub_vars["output_type"] = ClassName(method->output_type(), true);
 251
 252     // Note:  down_cast does not work here because it only works on pointers,
 253     //   not references.
 254     printer->Print(sub_vars,
 255       "    case $index$:\n"
 256       "      $name$(controller,\n"
 257       "             ::google::protobuf::down_cast<const $input_type$*>(request),\n"
 258       "             ::google::protobuf::down_cast< $output_type$*>(response),\n"
 259       "             done);\n"
 260       "      break;\n");
 261   }
 262
 263   printer->Print(vars_,
 264     "    default:\n"
 265     "      GOOGLE_LOG(FATAL) << \"Bad method index; this should never happen.\";\n"
 266     "      break;\n"
 267     "  }\n"
 268     "}\n"
 269     "\n");
 270 }
 271
 272 void ServiceGenerator::GenerateGetPrototype(RequestOrResponse which,
 273                                             io::Printer* printer) {
 274   if (which == REQUEST) {
 275     printer->Print(vars_,
 276       "const ::google::protobuf::Message& $classname$::GetRequestPrototype(\n");
 277   } else {
 278     printer->Print(vars_,
 279       "const ::google::protobuf::Message& $classname$::GetResponsePrototype(\n");
 280   }
 281
 282   printer->Print(vars_,
 283     "    const ::google::protobuf::MethodDescriptor* method) const {\n"
 284     "  GOOGLE_DCHECK_EQ(method->service(), descriptor());\n"
 285     "  switch(method->index()) {\n");
 286
 287   for (int i = 0; i < descriptor_->method_count(); i++) {
 288     const MethodDescriptor* method = descriptor_->method(i);
 289     const Descriptor* type =
 290       (which == REQUEST) ? method->input_type() : method->output_type();
 291
 292     map<string, string> sub_vars;
 293     sub_vars["index"] = SimpleItoa(i);
 294     sub_vars["type"] = ClassName(type, true);
 295
 296     printer->Print(sub_vars,
 297       "    case $index$:\n"
 298       "      return $type$::default_instance();\n");
 299   }
 300
 301   printer->Print(vars_,
 302     "    default:\n"
 303     "      GOOGLE_LOG(FATAL) << \"Bad method index; this should never happen.\";\n"
 304     "      return *reinterpret_cast< ::google::protobuf::Message*>(NULL);\n"
 305     "  }\n"
 306     "}\n"
 307     "\n");
 308 }
 309
 310 void ServiceGenerator::GenerateStubMethods(io::Printer* printer) {
 311   for (int i = 0; i < descriptor_->method_count(); i++) {
 312     const MethodDescriptor* method = descriptor_->method(i);
 313     map<string, string> sub_vars;
 314     sub_vars["classname"] = descriptor_->name();
 315     sub_vars["name"] = method->name();
 316     sub_vars["index"] = SimpleItoa(i);
 317     sub_vars["input_type"] = ClassName(method->input_type(), true);
 318     sub_vars["output_type"] = ClassName(method->output_type(), true);
 319
 320     printer->Print(sub_vars,
 321       "void $classname$_Stub::$name$(::google::protobuf::RpcController* controller,\n"
 322       "                              const $input_type$* request,\n"
 323       "                              $output_type$* response,\n"
 324       "                              ::google::protobuf::Closure* done) {\n"
 325       "  channel_->CallMethod(descriptor()->method($index$),\n"
 326       "                       controller, request, response, done);\n"
 327       "}\n");
 328   }
 329 }
 330
 331 }  // namespace cpp
 332 }  // namespace compiler
 333 }  // namespace protobuf
 334 }  // namespace google