src/main/tools/logging.h

// Copyright 2017 The Bazel Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SRC_MAIN_TOOLS_LOGGING_H_
#define SRC_MAIN_TOOLS_LOGGING_H_

// see
// http://stackoverflow.com/questions/5641427/how-to-make-preprocessor-generate-a-string-for-line-keyword
#define S(x) #x
#define S_(x) S(x)
#define S__LINE__ S_(__LINE__)

#define DIE(...)                                                \
  {                                                             \
    fprintf(stderr, __FILE__ ":" S__LINE__ ": \"" __VA_ARGS__); \
    fprintf(stderr, "\": ");                                    \
    perror(nullptr);                                            \
    exit(EXIT_FAILURE);                                         \
  }

#define PRINT_DEBUG(...)                                        \
  do {                                                          \
    if (global_debug) {                                         \
      fprintf(stderr, __FILE__ ":" S__LINE__ ": " __VA_ARGS__); \
      fprintf(stderr, "\n");                                    \
    }                                                           \
  } while (0)

// Set to `true` to let PRINT_DEBUG() print messages.
extern bool global_debug;

#endif  // SRC_MAIN_TOOLS_LOGGING_H_