blob: ff90a81645fddbd4b213d9318567fbfdb279089c [file] [log] [blame]
/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
// RTC_LOG(...) an ostream target that can be used to send formatted
// output to a variety of logging targets, such as debugger console, stderr,
// or any LogSink.
// The severity level passed as the first argument to the logging
// functions is used as a filter, to limit the verbosity of the logging.
// Static members of LogMessage documented below are used to control the
// verbosity and target of the output.
// There are several variations on the RTC_LOG macro which facilitate logging
// of common error conditions, detailed below.
// RTC_LOG(sev) logs the given stream at severity "sev", which must be a
// compile-time constant of the LoggingSeverity type, without the namespace
// prefix.
// RTC_LOG_V(sev) Like RTC_LOG(), but sev is a run-time variable of the
// LoggingSeverity type (basically, it just doesn't prepend the namespace).
// RTC_LOG_F(sev) Like RTC_LOG(), but includes the name of the current function.
// RTC_LOG_T(sev) Like RTC_LOG(), but includes the this pointer.
// RTC_LOG_T_F(sev) Like RTC_LOG_F(), but includes the this pointer.
// RTC_LOG_GLE(sev [, mod]) attempt to add a string description of the
// HRESULT returned by GetLastError.
// RTC_LOG_ERRNO(sev) attempts to add a string description of an errno-derived
// error. errno and associated facilities exist on both Windows and POSIX,
// but on Windows they only apply to the C/C++ runtime.
// RTC_LOG_ERR(sev) is an alias for the platform's normal error system, i.e.
// _GLE on Windows and _ERRNO on POSIX.
// (The above three also all have _EX versions that let you specify the error
// code, rather than using the last one.)
// RTC_LOG_E(sev, ctx, err, ...) logs a detailed error interpreted using the
// specified context.
// RTC_LOG_CHECK_LEVEL(sev) (and RTC_LOG_CHECK_LEVEL_V(sev)) can be used as a
// test before performing expensive or sensitive operations whose sole
// purpose is to output logging data at the desired level.
#ifndef RTC_BASE_LOGGING_H_
#define RTC_BASE_LOGGING_H_
#include <errno.h>
#include <list>
#include <sstream>
#include <string>
#include <utility>
#if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS)
#include <CoreServices/CoreServices.h>
#endif
#include "rtc_base/constructormagic.h"
#include "rtc_base/deprecation.h"
#include "rtc_base/system/no_inline.h"
#include "rtc_base/thread_annotations.h"
#if !defined(NDEBUG) || defined(DLOG_ALWAYS_ON)
#define RTC_DLOG_IS_ON 1
#else
#define RTC_DLOG_IS_ON 0
#endif
namespace rtc {
#if defined(WEBRTC_MAC) && !defined(WEBRTC_IOS)
// Returns a UTF8 description from an OS X Status error.
std::string DescriptionFromOSStatus(OSStatus err);
#endif
//////////////////////////////////////////////////////////////////////
// Note that the non-standard LoggingSeverity aliases exist because they are
// still in broad use. The meanings of the levels are:
// LS_SENSITIVE: Information which should only be logged with the consent
// of the user, due to privacy concerns.
// LS_VERBOSE: This level is for data which we do not want to appear in the
// normal debug log, but should appear in diagnostic logs.
// LS_INFO: Chatty level used in debugging for all sorts of things, the default
// in debug builds.
// LS_WARNING: Something that may warrant investigation.
// LS_ERROR: Something that should not have occurred.
// LS_NONE: Don't log.
enum LoggingSeverity {
LS_SENSITIVE,
LS_VERBOSE,
LS_INFO,
LS_WARNING,
LS_ERROR,
LS_NONE,
INFO = LS_INFO,
WARNING = LS_WARNING,
LERROR = LS_ERROR
};
// LogErrorContext assists in interpreting the meaning of an error value.
enum LogErrorContext {
ERRCTX_NONE,
ERRCTX_ERRNO, // System-local errno
ERRCTX_HRESULT, // Windows HRESULT
ERRCTX_OSSTATUS, // MacOS OSStatus
// Abbreviations for LOG_E macro
ERRCTX_EN = ERRCTX_ERRNO, // LOG_E(sev, EN, x)
ERRCTX_HR = ERRCTX_HRESULT, // LOG_E(sev, HR, x)
ERRCTX_OS = ERRCTX_OSSTATUS, // LOG_E(sev, OS, x)
};
// Virtual sink interface that can receive log messages.
class LogSink {
public:
LogSink() {}
virtual ~LogSink() {}
virtual void OnLogMessage(const std::string& msg,
LoggingSeverity severity,
const char* tag);
virtual void OnLogMessage(const std::string& message) = 0;
};
class LogMessage {
public:
LogMessage(const char* file, int line, LoggingSeverity sev);
// Same as the above, but using a compile-time constant for the logging
// severity. This saves space at the call site, since passing an empty struct
// is generally the same as not passing an argument at all.
template <LoggingSeverity S>
RTC_NO_INLINE LogMessage(const char* file,
int line,
std::integral_constant<LoggingSeverity, S>)
: LogMessage(file, line, S) {}
LogMessage(const char* file,
int line,
LoggingSeverity sev,
LogErrorContext err_ctx,
int err);
#if defined(WEBRTC_ANDROID)
LogMessage(const char* file, int line, LoggingSeverity sev, const char* tag);
#endif
// DEPRECATED - DO NOT USE - PLEASE USE THE MACROS INSTEAD OF THE CLASS.
// Android code should use the 'const char*' version since tags are static
// and we want to avoid allocating a std::string copy per log line.
RTC_DEPRECATED
LogMessage(const char* file, int line, LoggingSeverity sev,
const std::string& tag);
~LogMessage();
static bool Loggable(LoggingSeverity sev);
// Same as the above, but using a template argument instead of a function
// argument. (When the logging severity is statically known, passing it as a
// template argument instead of as a function argument saves space at the
// call site.)
template <LoggingSeverity S>
RTC_NO_INLINE static bool Loggable() {
return Loggable(S);
}
std::ostream& stream();
// Returns the time at which this function was called for the first time.
// The time will be used as the logging start time.
// If this is not called externally, the LogMessage ctor also calls it, in
// which case the logging start time will be the time of the first LogMessage
// instance is created.
static int64_t LogStartTime();
// Returns the wall clock equivalent of |LogStartTime|, in seconds from the
// epoch.
static uint32_t WallClockStartTime();
// LogThreads: Display the thread identifier of the current thread
static void LogThreads(bool on = true);
// LogTimestamps: Display the elapsed time of the program
static void LogTimestamps(bool on = true);
// These are the available logging channels
// Debug: Debug console on Windows, otherwise stderr
static void LogToDebug(LoggingSeverity min_sev);
static LoggingSeverity GetLogToDebug();
// Sets whether logs will be directed to stderr in debug mode.
static void SetLogToStderr(bool log_to_stderr);
// Stream: Any non-blocking stream interface. LogMessage takes ownership of
// the stream. Multiple streams may be specified by using AddLogToStream.
// LogToStream is retained for backwards compatibility; when invoked, it
// will discard any previously set streams and install the specified stream.
// GetLogToStream gets the severity for the specified stream, of if none
// is specified, the minimum stream severity.
// RemoveLogToStream removes the specified stream, without destroying it.
static int GetLogToStream(LogSink* stream = nullptr);
static void AddLogToStream(LogSink* stream, LoggingSeverity min_sev);
static void RemoveLogToStream(LogSink* stream);
// Testing against MinLogSeverity allows code to avoid potentially expensive
// logging operations by pre-checking the logging level.
static int GetMinLogSeverity();
// Parses the provided parameter stream to configure the options above.
// Useful for configuring logging from the command line.
static void ConfigureLogging(const char* params);
private:
friend class LogMessageForTesting;
typedef std::pair<LogSink*, LoggingSeverity> StreamAndSeverity;
typedef std::list<StreamAndSeverity> StreamList;
// Updates min_sev_ appropriately when debug sinks change.
static void UpdateMinLogSeverity();
// These write out the actual log messages.
#if defined(WEBRTC_ANDROID)
static void OutputToDebug(const std::string& msg,
LoggingSeverity severity,
const char* tag);
#else
static void OutputToDebug(const std::string& msg, LoggingSeverity severity);
#endif
// Checks the current global debug severity and if the |streams_| collection
// is empty. If |severity| is smaller than the global severity and if the
// |streams_| collection is empty, the LogMessage will be considered a noop
// LogMessage.
static bool IsNoop(LoggingSeverity severity);
// Called from the dtor (or from a test) to append optional extra error
// information to the log stream and a newline character.
void FinishPrintStream();
// The ostream that buffers the formatted message before output
std::ostringstream print_stream_;
// The severity level of this message
LoggingSeverity severity_;
#if defined(WEBRTC_ANDROID)
// The default Android debug output tag.
const char* tag_ = "libjingle";
#endif
// String data generated in the constructor, that should be appended to
// the message before output.
std::string extra_;
const bool is_noop_;
// The output streams and their associated severities
static StreamList streams_;
// Flags for formatting options
static bool thread_, timestamp_;
// Determines if logs will be directed to stderr in debug mode.
static bool log_to_stderr_;
RTC_DISALLOW_COPY_AND_ASSIGN(LogMessage);
};
//////////////////////////////////////////////////////////////////////
// Logging Helpers
//////////////////////////////////////////////////////////////////////
// The following non-obvious technique for implementation of a
// conditional log stream was stolen from google3/base/logging.h.
// This class is used to explicitly ignore values in the conditional
// logging macros. This avoids compiler warnings like "value computed
// is not used" and "statement has no effect".
class LogMessageVoidify {
public:
LogMessageVoidify() { }
// This has to be an operator with a precedence lower than << but
// higher than ?:
void operator&(std::ostream&) { }
};
#define RTC_LOG_SEVERITY_PRECONDITION(sev) \
!(rtc::LogMessage::Loggable(sev)) \
? (void) 0 \
: rtc::LogMessageVoidify() &
#define RTC_LOG_SEVERITY_PRECONDITION_C(sev) \
!(rtc::LogMessage::Loggable<rtc::sev>()) ? (void)0 : rtc::LogMessageVoidify()&
#define RTC_LOG(sev) \
RTC_LOG_SEVERITY_PRECONDITION_C(sev) \
rtc::LogMessage(__FILE__, __LINE__, \
std::integral_constant<rtc::LoggingSeverity, rtc::sev>()) \
.stream()
// The _V version is for when a variable is passed in. It doesn't do the
// namespace concatenation.
#define RTC_LOG_V(sev) \
RTC_LOG_SEVERITY_PRECONDITION(sev) \
rtc::LogMessage(__FILE__, __LINE__, sev).stream()
// The _F version prefixes the message with the current function name.
#if (defined(__GNUC__) && !defined(NDEBUG)) || defined(WANT_PRETTY_LOG_F)
#define RTC_LOG_F(sev) RTC_LOG(sev) << __PRETTY_FUNCTION__ << ": "
#define RTC_LOG_T_F(sev) RTC_LOG(sev) << this << ": " \
<< __PRETTY_FUNCTION__ << ": "
#else
#define RTC_LOG_F(sev) RTC_LOG(sev) << __FUNCTION__ << ": "
#define RTC_LOG_T_F(sev) RTC_LOG(sev) << this << ": " << __FUNCTION__ << ": "
#endif
#define RTC_LOG_CHECK_LEVEL(sev) \
rtc::LogCheckLevel(rtc::sev)
#define RTC_LOG_CHECK_LEVEL_V(sev) \
rtc::LogCheckLevel(sev)
inline bool LogCheckLevel(LoggingSeverity sev) {
return (LogMessage::GetMinLogSeverity() <= sev);
}
#define RTC_LOG_E(sev, ctx, err, ...) \
RTC_LOG_SEVERITY_PRECONDITION_C(sev) \
rtc::LogMessage(__FILE__, __LINE__, rtc::sev, rtc::ERRCTX_##ctx, err, \
##__VA_ARGS__) \
.stream()
#define RTC_LOG_T(sev) RTC_LOG(sev) << this << ": "
#define RTC_LOG_ERRNO_EX(sev, err) \
RTC_LOG_E(sev, ERRNO, err)
#define RTC_LOG_ERRNO(sev) \
RTC_LOG_ERRNO_EX(sev, errno)
#if defined(WEBRTC_WIN)
#define RTC_LOG_GLE_EX(sev, err) \
RTC_LOG_E(sev, HRESULT, err)
#define RTC_LOG_GLE(sev) \
RTC_LOG_GLE_EX(sev, GetLastError())
#define RTC_LOG_ERR_EX(sev, err) \
RTC_LOG_GLE_EX(sev, err)
#define RTC_LOG_ERR(sev) \
RTC_LOG_GLE(sev)
#elif defined(__native_client__) && __native_client__
#define RTC_LOG_ERR_EX(sev, err) \
RTC_LOG(sev)
#define RTC_LOG_ERR(sev) \
RTC_LOG(sev)
#elif defined(WEBRTC_POSIX)
#define RTC_LOG_ERR_EX(sev, err) \
RTC_LOG_ERRNO_EX(sev, err)
#define RTC_LOG_ERR(sev) \
RTC_LOG_ERRNO(sev)
#endif // WEBRTC_WIN
#if defined(WEBRTC_ANDROID)
namespace internal {
// Inline adapters provided for backwards compatibility for downstream projects.
inline const char* AdaptString(const char* str) { return str; }
inline const char* AdaptString(const std::string& str) { return str.c_str(); }
} // namespace internal
#define RTC_LOG_TAG(sev, tag) \
RTC_LOG_SEVERITY_PRECONDITION(sev) \
rtc::LogMessage(nullptr, 0, sev, rtc::internal::AdaptString(tag)).stream()
#else
// DEPRECATED. This macro is only intended for Android.
#define RTC_LOG_TAG(sev, tag) \
RTC_LOG_SEVERITY_PRECONDITION(sev) \
rtc::LogMessage(nullptr, 0, sev).stream()
#endif
// The RTC_DLOG macros are equivalent to their RTC_LOG counterparts except that
// they only generate code in debug builds.
#if RTC_DLOG_IS_ON
#define RTC_DLOG(sev) RTC_LOG(sev)
#define RTC_DLOG_V(sev) RTC_LOG_V(sev)
#define RTC_DLOG_F(sev) RTC_LOG_F(sev)
#else
#define RTC_DLOG_EAT_STREAM_PARAMS(sev) \
(true ? true : ((void)(sev), true)) \
? static_cast<void>(0) \
: rtc::LogMessageVoidify() & \
rtc::LogMessage(__FILE__, __LINE__, sev).stream()
#define RTC_DLOG(sev) RTC_DLOG_EAT_STREAM_PARAMS(rtc::sev)
#define RTC_DLOG_V(sev) RTC_DLOG_EAT_STREAM_PARAMS(sev)
#define RTC_DLOG_F(sev) RTC_DLOG_EAT_STREAM_PARAMS(rtc::sev)
#endif
} // namespace rtc
#endif // RTC_BASE_LOGGING_H_