rocksdb/logging/log_buffer.h
Peter Dillinger 4e60663b31 Remove unnecessary, confusing 'extern' (#12300)
Summary:
In C++, `extern` is redundant in a number of cases:
* "Global" function declarations and definitions
* "Global" variable definitions when already declared `extern`

For consistency and simplicity, I've removed these in code that *we own*. In a couple of cases, I removed obsolete declarations, and for MagicNumber constants, I have consolidated the declarations into a header file (format.h)
as standard best practice would prescribe.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12300

Test Plan: no functional changes, CI

Reviewed By: ajkr

Differential Revision: D53148629

Pulled By: pdillinger

fbshipit-source-id: fb8d927959892e03af09b0c0d542b0a3b38fd886
2024-01-29 10:38:08 -08:00

58 lines
1.8 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include <ctime>
#include "memory/arena.h"
#include "port/sys_time.h"
#include "rocksdb/env.h"
#include "util/autovector.h"
namespace ROCKSDB_NAMESPACE {
class Logger;
// A class to buffer info log entries and flush them in the end.
class LogBuffer {
public:
// log_level: the log level for all the logs
// info_log: logger to write the logs to
LogBuffer(const InfoLogLevel log_level, Logger* info_log);
// Add a log entry to the buffer. Use default max_log_size.
// max_log_size indicates maximize log size, including some metadata.
void AddLogToBuffer(size_t max_log_size, const char* format, va_list ap);
size_t IsEmpty() const { return logs_.empty(); }
// Flush all buffered log to the info log.
void FlushBufferToLog();
static const size_t kDefaultMaxLogSize = 512;
private:
// One log entry with its timestamp
struct BufferedLog {
port::TimeVal now_tv; // Timestamp of the log
char message[1]; // Beginning of log message
};
const InfoLogLevel log_level_;
Logger* info_log_;
Arena arena_;
autovector<BufferedLog*> logs_;
};
// Add log to the LogBuffer for a delayed info logging. It can be used when
// we want to add some logs inside a mutex.
// max_log_size indicates maximize log size, including some metadata.
void LogToBuffer(LogBuffer* log_buffer, size_t max_log_size, const char* format,
...);
// Same as previous function, but with default max log size.
void LogToBuffer(LogBuffer* log_buffer, const char* format, ...);
} // namespace ROCKSDB_NAMESPACE