llvm/lldb/include/lldb/Utility/Log.h

//===-- Log.h ---------------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef LLDB_UTILITY_LOG_H
#define LLDB_UTILITY_LOG_H

#include "lldb/Utility/Flags.h"
#include "lldb/lldb-defines.h"

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/RWMutex.h"

#include <atomic>
#include <cstdarg>
#include <cstdint>
#include <memory>
#include <mutex>
#include <string>
#include <type_traits>

namespace llvm {
class raw_ostream;
}
// Logging Options
#define LLDB_LOG_OPTION_VERBOSE …
#define LLDB_LOG_OPTION_PREPEND_SEQUENCE …
#define LLDB_LOG_OPTION_PREPEND_TIMESTAMP …
#define LLDB_LOG_OPTION_PREPEND_PROC_AND_THREAD …
#define LLDB_LOG_OPTION_PREPEND_THREAD_NAME …
#define LLDB_LOG_OPTION_BACKTRACE …
#define LLDB_LOG_OPTION_APPEND …
#define LLDB_LOG_OPTION_PREPEND_FILE_FUNCTION …

// Logging Functions
namespace lldb_private {

class LogHandler { … };

class StreamLogHandler : public LogHandler { … };

class CallbackLogHandler : public LogHandler { … };

class RotatingLogHandler : public LogHandler { … };

/// A T-style log handler that multiplexes messages to two log handlers.
class TeeLogHandler : public LogHandler { … };

class Log final { … };

// Must be specialized for a particular log type.
template <typename Cat> Log::Channel &LogChannelFor() = delete;

/// Retrieve the Log object for the channel associated with the given log enum.
///
/// Returns a valid Log object if any of the provided categories are enabled.
/// Otherwise, returns nullptr.
template <typename Cat> Log *GetLog(Cat mask) { … }

} // namespace lldb_private

/// The LLDB_LOG* macros defined below are the way to emit log messages.
///
/// Note that the macros surround the arguments in a check for the log
/// being on, so you can freely call methods in arguments without affecting
/// the non-log execution flow.
///
/// If you need to do more complex computations to prepare the log message
/// be sure to add your own if (log) check, since we don't want logging to
/// have any effect when not on.
///
/// However, the LLDB_LOG macro uses the llvm::formatv system (see the
/// ProgrammersManual page in the llvm docs for more details).  This allows
/// the use of "format_providers" to auto-format datatypes, and there are
/// already formatters for some of the llvm and lldb datatypes.
///
/// So if you need to do non-trivial formatting of one of these types, be
/// sure to grep the lldb and llvm sources for "format_provider" to see if
/// there is already a formatter before doing in situ formatting, and if
/// possible add a provider if one does not already exist.

#define LLDB_LOG(log, ...) …

#define LLDB_LOGF(log, ...) …

#define LLDB_LOGV(log, ...) …

// Write message to log, if error is set. In the log message refer to the error
// with {0}. Error is cleared regardless of whether logging is enabled.
#define LLDB_LOG_ERROR(log, error, ...) …

// Write message to the verbose log, if error is set. In the log
// message refer to the error with {0}. Error is cleared regardless of
// whether logging is enabled.
#define LLDB_LOG_ERRORV(log, error, ...) …

#endif // LLDB_UTILITY_LOG_H