src/glog/raw_logging.h.in

// Copyright 2006 Google Inc. All Rights Reserved.
// Author: Maxim Lifantsev
//
// Logging routines that do not allocate any memory and acquire any
// locks, and can therefore be used by low-level memory allocation
// and synchronization code.

#ifndef BASE_RAW_LOGGING_H__
#define BASE_RAW_LOGGING_H__

@ac_google_start_namespace@

#include "glog/log_severity.h"
#include "glog/vlog_is_on.h"

// This is similar to LOG(severity) << format... and VLOG(level) << format..,
// but
// * it is to be used ONLY by low-level modules that can't use normal LOG()
// * it is desiged to be a low-level logger that does not allocate any
//   memory and does not need any locks, hence:
// * it logs straight and ONLY to STDERR w/o buffering
// * it uses an explicit format and arguments list
// * it will silently chop off really long message strings
// Usage example:
//   RAW_LOG(ERROR, "Failed foo with %i: %s", status, error);
//   RAW_VLOG(3, "status is %i", status);
// These will print an almost standard log lines like this to stderr only:
//   E0821 211317 file.cc:123] RAW: Failed foo with 22: bad_file
//   I0821 211317 file.cc:142] RAW: status is 20
#define RAW_LOG(severity, ...) \
  do { \
    @ac_google_namespace@::RawLog__(@ac_google_namespace@::severity, __FILE__,  __LINE__, __VA_ARGS__); \
  } while (0)

#define RAW_VLOG(verboselevel, ...) \
  do { \
    if (VLOG_IS_ON(verboselevel)) { \
      @ac_google_namespace@::RawLog__(@ac_google_namespace@::INFO, __FILE__,  __LINE__, __VA_ARGS__); \
    } \
  } while (0)

// Similar to CHECK(condition) << message,
// but for low-level modules: we use only RAW_LOG that does not allocate memory.
// We do not want to provide args list here to encourage this usage:
//   if (!cond)  RAW_LOG(FATAL, "foo ...", hard_to_compute_args);
// so that the args are not computed when not needed.
#define RAW_CHECK(condition, message) \
  do { \
    if (!(condition)) { \
      RAW_LOG(FATAL, "Check %s failed: %s", #condition, message); \
    } \
  } while (0)

// Debug versions of RAW_LOG and RAW_CHECK
#ifndef NDEBUG

#define RAW_DLOG(severity, ...) RAW_LOG(severity, __VA_ARGS__)
#define RAW_DCHECK(condition, message) RAW_CHECK(condition, message)

#else  // NDEBUG

#define RAW_DLOG(severity, ...) \
  while (false) \
    RAW_LOG(severity, __VA_ARGS__)
#define RAW_DCHECK(condition, message) \
  while (false) \
    RAW_CHECK(condition, message)

#endif  // NDEBUG

// Helper function to implement RAW_LOG and RAW_VLOG
// Logs format... at "severity" level, reporting it
// as called from file:line.
// This does not allocate memory or acquire locks.
void RawLog__(LogSeverity severity, const char* file, int line,
              const char* format, ...)
   @ac_cv___attribute___printf_4_5@;

// Hack to propagate time information into this module so that
// this module does not have to directly call localtime_r(),
// which could allocate memory.
extern "C" struct ::tm;
void RawLog__SetLastTime(const struct ::tm& t);

@ac_google_end_namespace@

#endif  // BASE_RAW_LOGGING_H__