blob: 9a21400b096d539566510891b8e58685ba4ca001 [file] [log] [blame]
#ifndef BENCHMARK_LOG_H_
#define BENCHMARK_LOG_H_
#include <iostream>
#include <ostream>
// NOTE: this is also defined in benchmark.h but we're trying to avoid a
// dependency.
// The _MSVC_LANG check should detect Visual Studio 2015 Update 3 and newer.
#if __cplusplus >= 201103L || (defined(_MSVC_LANG) && _MSVC_LANG >= 201103L)
#define BENCHMARK_HAS_CXX11
#endif
namespace benchmark {
namespace internal {
typedef std::basic_ostream<char>&(EndLType)(std::basic_ostream<char>&);
class LogType {
friend LogType& GetNullLogInstance();
friend LogType& GetErrorLogInstance();
// FIXME: Add locking to output.
template <class Tp>
friend LogType& operator<<(LogType&, Tp const&);
friend LogType& operator<<(LogType&, EndLType*);
private:
LogType(std::ostream* out) : out_(out) {}
std::ostream* out_;
// NOTE: we could use BENCHMARK_DISALLOW_COPY_AND_ASSIGN but we shouldn't have
// a dependency on benchmark.h from here.
#ifndef BENCHMARK_HAS_CXX11
LogType(const LogType&);
LogType& operator=(const LogType&);
#else
LogType(const LogType&) = delete;
LogType& operator=(const LogType&) = delete;
#endif
};
template <class Tp>
LogType& operator<<(LogType& log, Tp const& value) {
if (log.out_) {
*log.out_ << value;
}
return log;
}
inline LogType& operator<<(LogType& log, EndLType* m) {
if (log.out_) {
*log.out_ << m;
}
return log;
}
inline int& LogLevel() {
static int log_level = 0;
return log_level;
}
inline LogType& GetNullLogInstance() {
static LogType null_log(static_cast<std::ostream*>(nullptr));
return null_log;
}
inline LogType& GetErrorLogInstance() {
static LogType error_log(&std::clog);
return error_log;
}
inline LogType& GetLogInstanceForLevel(int level) {
if (level <= LogLevel()) {
return GetErrorLogInstance();
}
return GetNullLogInstance();
}
} // end namespace internal
} // end namespace benchmark
// clang-format off
#define BM_VLOG(x) \
(::benchmark::internal::GetLogInstanceForLevel(x) << "-- LOG(" << x << "):" \
" ")
// clang-format on
#endif