1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // Logging macros, similar to Chromium's base/logging.h, except with |MOJO_| 6 // prefixes and missing some features (notably |CHECK_EQ()|, etc.). 7 8 // TODO(vtl): It's weird that this is in the environment directory, since its 9 // implementation (in environment/lib) is meant to be used by any implementation 10 // of the environment. 11 12 #ifndef MOJO_PUBLIC_CPP_ENVIRONMENT_LOGGING_H_ 13 #define MOJO_PUBLIC_CPP_ENVIRONMENT_LOGGING_H_ 14 15 #include <sstream> 16 17 #include "mojo/public/c/environment/logger.h" 18 #include "mojo/public/cpp/environment/environment.h" 19 #include "mojo/public/cpp/system/macros.h" 20 21 #define MOJO_LOG_STREAM(level) \ 22 ::mojo::internal::LogMessage(__FILE__, __LINE__, \ 23 MOJO_LOG_LEVEL_ ## level).stream() 24 25 #define MOJO_LAZY_LOG_STREAM(level, condition) \ 26 !(condition) ? \ 27 (void) 0 : \ 28 ::mojo::internal::VoidifyOstream() & MOJO_LOG_STREAM(level) 29 30 #define MOJO_SHOULD_LOG(level) \ 31 (MOJO_LOG_LEVEL_ ## level >= \ 32 ::mojo::Environment::GetDefaultLogger()->GetMinimumLogLevel()) 33 34 #define MOJO_LOG(level) \ 35 MOJO_LAZY_LOG_STREAM(level, MOJO_SHOULD_LOG(level)) 36 37 #define MOJO_LOG_IF(level, condition) \ 38 MOJO_LAZY_LOG_STREAM(level, MOJO_SHOULD_LOG(level) && (condition)) 39 40 #define MOJO_CHECK(condition) \ 41 MOJO_LAZY_LOG_STREAM(FATAL, !(condition)) \ 42 << "Check failed: " #condition ". " 43 44 // Note: For non-debug builds, |MOJO_DLOG_IF()| *eliminates* (i.e., doesn't 45 // compile) the condition, whereas |MOJO_DCHECK()| "neuters" the condition 46 // (i.e., compiles, but doesn't evaluate). 47 #ifdef NDEBUG 48 49 #define MOJO_DLOG(level) MOJO_LAZY_LOG_STREAM(level, false) 50 #define MOJO_DLOG_IF(level, condition) MOJO_LAZY_LOG_STREAM(level, false) 51 #define MOJO_DCHECK(condition) MOJO_LAZY_LOG_STREAM(FATAL, false && (condition)) 52 53 #else 54 55 #define MOJO_DLOG(level) MOJO_LOG(level) 56 #define MOJO_DLOG_IF(level, condition) MOJO_LOG_IF(level, condition) 57 #define MOJO_DCHECK(condition) MOJO_CHECK(condition) 58 59 #endif // NDEBUG 60 61 namespace mojo { 62 namespace internal { 63 64 class LogMessage { 65 public: 66 LogMessage(const char* file, int line, MojoLogLevel log_level); 67 ~LogMessage(); 68 stream()69 std::ostream& stream() { return stream_; } 70 71 private: 72 const MojoLogLevel log_level_; 73 std::ostringstream stream_; 74 75 MOJO_DISALLOW_COPY_AND_ASSIGN(LogMessage); 76 }; 77 78 // Used to ignore a stream. 79 struct VoidifyOstream { 80 // Use & since it has precedence lower than << but higher than ?:. 81 void operator&(std::ostream&) {} 82 }; 83 84 } // namespace internal 85 } // namespace mojo 86 87 #endif // MOJO_PUBLIC_CPP_ENVIRONMENT_LOGGING_H_ 88