fix: unify LogMessage and LogMessageInfo (#1057)
Deprecate the custom prefix callback accepting LogMessageInfo in favor
of existing LogMessage data structure extended with necessary data
fields to avoid redundancies.
diff --git a/.bazelci/presubmit.yml b/.bazelci/presubmit.yml
index 04a5385..87bd2a0 100644
--- a/.bazelci/presubmit.yml
+++ b/.bazelci/presubmit.yml
@@ -1,8 +1,8 @@
---
tasks:
ubuntu1804:
- name: "Ubuntu 18.04"
- platform: ubuntu1804
+ name: "Ubuntu 22.04"
+ platform: ubuntu2204
build_flags:
- "--features=layering_check"
- "--copt=-Werror"
diff --git a/README.rst b/README.rst
index c247d14..d9f4374 100644
--- a/README.rst
+++ b/README.rst
@@ -320,6 +320,54 @@
caution when comparing the low bits of timestamps from different machines.
+Customizing the Log Line Prefix
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The predefined log line prefix can be replaced using a user-provided callback
+that formats the corresponding output.
+
+For each log entry, the callback will be invoked with a reference to a
+``google::LogMessage`` instance containing the severity, filename, line number,
+thread ID, and time of the event. It will also be given a reference to the
+output stream, whose contents will be prepended to the actual message in the
+final log line.
+
+For example, the following function outputs a prefix that matches glog's default
+format. The third parameter ``data`` can be used to access user-supplied data
+which unless specified defaults to :cpp:`nullptr`.
+
+.. code:: cpp
+
+ void MyPrefixFormatter(std::ostream& s, const google::LogMessage& m, void* /*data*/) {
+ s << google::GetLogSeverityName(m.severity())[0]
+ << setw(4) << 1900 + m.time().year()
+ << setw(2) << 1 + m.time().month()
+ << setw(2) << m.time().day()
+ << ' '
+ << setw(2) << m.time().hour() << ':'
+ << setw(2) << m.time().min() << ':'
+ << setw(2) << m.time().sec() << "."
+ << setw(6) << m.time().usec()
+ << ' '
+ << setfill(' ') << setw(5)
+ << m.thread_id() << setfill('0')
+ << ' '
+ << m.basename() << ':' << m.line() << "]";
+ }
+
+
+To enable the use of a prefix formatter, use the
+
+.. code:: cpp
+
+ google::InstallPrefixFormatter(&MyPrefixFormatter);
+
+function to pass a pointer to the corresponding :cpp:`MyPrefixFormatter`
+callback during initialization. :cpp:`InstallPrefixFormatter` takes a second
+optional argument of type :cpp:`void*` that allows supplying user data to the
+callback.
+
+
Setting Flags
~~~~~~~~~~~~~
@@ -650,50 +698,6 @@
"Present occurrence is " << google::COUNTER;
-Custom Log Prefix Format
-~~~~~~~~~~~~~~~~~~~~~~~~
-
-glog supports changing the format of the prefix attached to log messages by
-receiving a user-provided callback that generates such strings.
-
-For each log entry, the callback will be invoked with a ``LogMessageInfo``
-struct containing the severity, filename, line number, thread ID, and time of
-the event. It will also be given a reference to the output stream, whose
-contents will be prepended to the actual message in the final log line.
-
-For example, the following function outputs a prefix that matches glog's default
-format. The third parameter ``data`` can be used to access user-supplied data
-which unless specified defaults to :cpp:`nullptr`.
-
-.. code:: cpp
-
- void CustomPrefix(std::ostream& s, const LogMessageInfo& l, void* /*data*/) {
- s << l.severity[0]
- << setw(4) << 1900 + l.time.year()
- << setw(2) << 1 + l.time.month()
- << setw(2) << l.time.day()
- << ' '
- << setw(2) << l.time.hour() << ':'
- << setw(2) << l.time.min() << ':'
- << setw(2) << l.time.sec() << "."
- << setw(6) << l.time.usec()
- << ' '
- << setfill(' ') << setw(5)
- << l.thread_id << setfill('0')
- << ' '
- << l.filename << ':' << l.line_number << "]";
- }
-
-
-To enable the use of a custom prefix, use the
-
-.. code:: cpp
-
- InitGoogleLogging(argv[0], &CustomPrefix);
-
-overload to pass a pointer to the corresponding :cpp:`CustomPrefix` function during
-initialization. :cpp:`InitGoogleLogging()` takes a third optional argument of
-type :cpp:`void*` that allows supplying user data to the callback.
Failure Signal Handler
~~~~~~~~~~~~~~~~~~~~~~
diff --git a/src/glog/logging.h b/src/glog/logging.h
index f4d6b4d..6e3ea26 100644
--- a/src/glog/logging.h
+++ b/src/glog/logging.h
@@ -115,7 +115,7 @@
std::chrono::seconds gmtoffset_;
};
-struct LogMessageInfo {
+struct [[deprecated("Use LogMessage instead.")]] LogMessageInfo {
explicit LogMessageInfo(const char* const severity_,
const char* const filename_, const int& line_number_,
std::thread::id thread_id_,
@@ -133,9 +133,6 @@
const LogMessageTime& time;
};
-typedef void (*CustomPrefixCallback)(std::ostream& s, const LogMessageInfo& l,
- void* data);
-
} // namespace google
// The global value of GOOGLE_STRIP_LOG. All the messages logged to
@@ -485,9 +482,26 @@
// specified by argv0 in log outputs.
GLOG_EXPORT void InitGoogleLogging(const char* argv0);
-GLOG_EXPORT void InitGoogleLogging(const char* argv0,
- CustomPrefixCallback prefix_callback,
- void* prefix_callback_data = nullptr);
+class LogMessage;
+
+#if defined(__GNUG__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(_MSC_VER)
+# pragma warning(push)
+# pragma warning(disable : 4996)
+#endif // __GNUG__
+using CustomPrefixCallback
+ [[deprecated("Use PrefixFormatterCallback instead.")]] =
+ void (*)(std::ostream&, const LogMessageInfo&, void*);
+#if defined(__GNUG__)
+# pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+# pragma warning(pop)
+#endif // __GNUG__
+[[deprecated("Use InstallPrefixFormatter instead.")]] GLOG_EXPORT void
+InitGoogleLogging(const char* argv0, CustomPrefixCallback prefix_callback,
+ void* prefix_callback_data = nullptr);
// Check if google's logging library has been initialized.
GLOG_EXPORT bool IsGoogleLoggingInitialized();
@@ -501,6 +515,12 @@
typedef void (*logging_fail_func_t)();
#endif
+using PrefixFormatterCallback = void (*)(std::ostream&, const LogMessage&,
+ void*);
+
+GLOG_EXPORT void InstallPrefixFormatter(PrefixFormatterCallback callback,
+ void* data = nullptr);
+
// Install a function which will be called after LOG(FATAL).
GLOG_EXPORT void InstallFailureFunction(logging_fail_func_t fail_func);
@@ -1343,9 +1363,15 @@
return time();
}
- const LogMessageTime& time() const;
+ LogSeverity severity() const noexcept;
+ int line() const noexcept;
+ const std::thread::id& thread_id() const noexcept;
+ const char* fullname() const noexcept;
+ const char* basename() const noexcept;
+ const LogMessageTime& time() const noexcept;
- struct LogMessageData;
+ LogMessage(const LogMessage&) = delete;
+ LogMessage& operator=(const LogMessage&) = delete;
private:
// Fully internal SendMethod cases:
@@ -1373,9 +1399,6 @@
LogMessageTime time_;
friend class LogDestination;
-
- LogMessage(const LogMessage&);
- void operator=(const LogMessage&);
};
// This class happens to be thread-hostile because all instances share
@@ -1493,7 +1516,7 @@
// during this call.
virtual void send(LogSeverity severity, const char* full_filename,
const char* base_filename, int line,
- const LogMessageTime& logmsgtime, const char* message,
+ const LogMessageTime& time, const char* message,
size_t message_len);
// Provide an overload for compatibility purposes
GLOG_DEPRECATED
@@ -1519,8 +1542,8 @@
// Returns the normal text output of the log message.
// Can be useful to implement send().
static std::string ToString(LogSeverity severity, const char* file, int line,
- const LogMessageTime& logmsgtime,
- const char* message, size_t message_len);
+ const LogMessageTime& time, const char* message,
+ size_t message_len);
};
// Add or remove a LogSink as a consumer of logging data. Thread-safe.
diff --git a/src/logging.cc b/src/logging.cc
index f9ffa70..f95fb61 100644
--- a/src/logging.cc
+++ b/src/logging.cc
@@ -307,10 +307,10 @@
const char* fullname_; // fullname of file that called LOG
bool has_been_flushed_; // false => data has not been flushed
bool first_fatal_; // true => this was first fatal msg
+ std::thread::id thread_id_;
- private:
LogMessageData(const LogMessageData&) = delete;
- void operator=(const LogMessageData&) = delete;
+ LogMessageData& operator=(const LogMessageData&) = delete;
};
} // namespace internal
} // namespace logging
@@ -370,9 +370,78 @@
constexpr std::intmax_t kSecondsInWeek = kSecondsInDay * 7;
// Optional user-configured callback to print custom prefixes.
-CustomPrefixCallback custom_prefix_callback = nullptr;
-// User-provided data to pass to the callback:
-void* custom_prefix_callback_data = nullptr;
+class PrefixFormatter {
+ public:
+#if defined(__GNUG__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(_MSC_VER)
+# pragma warning(push)
+# pragma warning(disable : 4996)
+#endif // __GNUG__
+ PrefixFormatter(CustomPrefixCallback callback, void* data) noexcept
+ : version{V1}, callback_v1{callback}, data{data} {}
+#if defined(__GNUG__)
+# pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+# pragma warning(pop)
+#endif // __GNUG__
+ PrefixFormatter(PrefixFormatterCallback callback, void* data) noexcept
+ : version{V2}, callback_v2{callback}, data{data} {}
+
+ void operator()(std::ostream& s, const LogMessage& message) const {
+ switch (version) {
+ case V1:
+#if defined(__GNUG__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(_MSC_VER)
+# pragma warning(push)
+# pragma warning(disable : 4996)
+#endif // __GNUG__
+ callback_v1(s,
+ LogMessageInfo(LogSeverityNames[message.severity()],
+ message.basename(), message.line(),
+ message.thread_id(), message.time()),
+ data);
+#if defined(__GNUG__)
+# pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+# pragma warning(pop)
+#endif // __GNUG__
+ break;
+ case V2:
+ callback_v2(s, message, data);
+ break;
+ }
+ }
+
+ PrefixFormatter(const PrefixFormatter& other) = delete;
+ PrefixFormatter& operator=(const PrefixFormatter& other) = delete;
+
+ private:
+ enum Version { V1, V2 } version;
+ union {
+#if defined(__GNUG__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(_MSC_VER)
+# pragma warning(push)
+# pragma warning(disable : 4996)
+#endif // __GNUG__
+ CustomPrefixCallback callback_v1;
+#if defined(__GNUG__)
+# pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+# pragma warning(pop)
+#endif // __GNUG__
+ PrefixFormatterCallback callback_v2;
+ };
+ // User-provided data to pass to the callback:
+ void* data;
+};
+
+std::unique_ptr<PrefixFormatter> g_prefix_formatter;
// Encapsulates all file-system related state
class LogFileObject : public base::Logger {
@@ -544,7 +613,7 @@
// Send logging info to all registered sinks.
static void LogToSinks(LogSeverity severity, const char* full_filename,
const char* base_filename, int line,
- const LogMessageTime& logmsgtime, const char* message,
+ const LogMessageTime& time, const char* message,
size_t message_len);
// Wait for all registered sinks via WaitTillSent
@@ -844,14 +913,14 @@
inline void LogDestination::LogToSinks(LogSeverity severity,
const char* full_filename,
const char* base_filename, int line,
- const LogMessageTime& logmsgtime,
+ const LogMessageTime& time,
const char* message,
size_t message_len) {
std::shared_lock<SinkMutex> l{sink_mutex_};
if (sinks_) {
for (size_t i = sinks_->size(); i-- > 0;) {
- (*sinks_)[i]->send(severity, full_filename, base_filename, line,
- logmsgtime, message, message_len);
+ (*sinks_)[i]->send(severity, full_filename, base_filename, line, time,
+ message, message_len);
}
}
}
@@ -1602,6 +1671,7 @@
data_->basename_ = const_basename(file);
data_->fullname_ = file;
data_->has_been_flushed_ = false;
+ data_->thread_id_ = std::this_thread::get_id();
// If specified, prepend a prefix to each line. For example:
// I20201018 160715 f5d4fbb0 logging.cc:1153]
@@ -1611,7 +1681,7 @@
std::ios saved_fmt(nullptr);
saved_fmt.copyfmt(stream());
stream().fill('0');
- if (custom_prefix_callback == nullptr) {
+ if (g_prefix_formatter == nullptr) {
stream() << LogSeverityNames[severity][0];
if (FLAGS_log_year_in_prefix) {
stream() << setw(4) << 1900 + time_.year();
@@ -1620,14 +1690,10 @@
<< setw(2) << time_.hour() << ':' << setw(2) << time_.min()
<< ':' << setw(2) << time_.sec() << "." << setw(6)
<< time_.usec() << ' ' << setfill(' ') << setw(5)
- << std::this_thread::get_id() << setfill('0') << ' '
- << data_->basename_ << ':' << data_->line_ << "] ";
+ << data_->thread_id_ << setfill('0') << ' ' << data_->basename_
+ << ':' << data_->line_ << "] ";
} else {
- custom_prefix_callback(
- stream(),
- LogMessageInfo(LogSeverityNames[severity], data_->basename_,
- data_->line_, std::this_thread::get_id(), time_),
- custom_prefix_callback_data);
+ (*g_prefix_formatter)(stream(), *this);
stream() << " ";
}
stream().copyfmt(saved_fmt);
@@ -1647,7 +1713,15 @@
}
}
-const LogMessageTime& LogMessage::time() const { return time_; }
+LogSeverity LogMessage::severity() const noexcept { return data_->severity_; }
+
+int LogMessage::line() const noexcept { return data_->line_; }
+const std::thread::id& LogMessage::thread_id() const noexcept {
+ return data_->thread_id_;
+}
+const char* LogMessage::fullname() const noexcept { return data_->fullname_; }
+const char* LogMessage::basename() const noexcept { return data_->basename_; }
+const LogMessageTime& LogMessage::time() const noexcept { return time_; }
LogMessage::~LogMessage() {
Flush();
@@ -2039,21 +2113,20 @@
}
string LogSink::ToString(LogSeverity severity, const char* file, int line,
- const LogMessageTime& logmsgtime, const char* message,
+ const LogMessageTime& time, const char* message,
size_t message_len) {
ostringstream stream;
stream.fill('0');
stream << LogSeverityNames[severity][0];
if (FLAGS_log_year_in_prefix) {
- stream << setw(4) << 1900 + logmsgtime.year();
+ stream << setw(4) << 1900 + time.year();
}
- stream << setw(2) << 1 + logmsgtime.month() << setw(2) << logmsgtime.day()
- << ' ' << setw(2) << logmsgtime.hour() << ':' << setw(2)
- << logmsgtime.min() << ':' << setw(2) << logmsgtime.sec() << '.'
- << setw(6) << logmsgtime.usec() << ' ' << setfill(' ') << setw(5)
- << std::this_thread::get_id() << setfill('0') << ' ' << file << ':'
- << line << "] ";
+ stream << setw(2) << 1 + time.month() << setw(2) << time.day() << ' '
+ << setw(2) << time.hour() << ':' << setw(2) << time.min() << ':'
+ << setw(2) << time.sec() << '.' << setw(6) << time.usec() << ' '
+ << setfill(' ') << setw(5) << std::this_thread::get_id()
+ << setfill('0') << ' ' << file << ':' << line << "] ";
// A call to `write' is enclosed in parenthneses to prevent possible macro
// expansion. On Windows, `write' could be a macro defined for portability.
@@ -2624,17 +2697,42 @@
void InitGoogleLogging(const char* argv0) { InitGoogleLoggingUtilities(argv0); }
+#if defined(__GNUG__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#elif defined(_MSC_VER)
+# pragma warning(push)
+# pragma warning(disable : 4996)
+#endif // __GNUG__
void InitGoogleLogging(const char* argv0, CustomPrefixCallback prefix_callback,
void* prefix_callback_data) {
- custom_prefix_callback = prefix_callback;
- custom_prefix_callback_data = prefix_callback_data;
+ if (prefix_callback != nullptr) {
+ g_prefix_formatter = std::make_unique<PrefixFormatter>(
+ prefix_callback, prefix_callback_data);
+ } else {
+ g_prefix_formatter = nullptr;
+ }
InitGoogleLogging(argv0);
}
+#if defined(__GNUG__)
+# pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+# pragma warning(pop)
+#endif // __GNUG__
+
+void InstallPrefixFormatter(PrefixFormatterCallback callback, void* data) {
+ if (callback != nullptr) {
+ g_prefix_formatter = std::make_unique<PrefixFormatter>(callback, data);
+ } else {
+ g_prefix_formatter = nullptr;
+ }
+}
void ShutdownGoogleLogging() {
ShutdownGoogleLoggingUtilities();
LogDestination::DeleteLogDestinations();
logging_directories_list = nullptr;
+ g_prefix_formatter = nullptr;
}
void EnableLogCleaner(unsigned int overdue_days) {
diff --git a/src/logging_unittest.cc b/src/logging_unittest.cc
index dde1fbf..1c5153b 100644
--- a/src/logging_unittest.cc
+++ b/src/logging_unittest.cc
@@ -185,23 +185,27 @@
}
BENCHMARK(BM_vlog)
+namespace {
+
// Dynamically generate a prefix using the default format and write it to the
// stream.
-void PrefixAttacher(std::ostream& s, const LogMessageInfo& l, void* data) {
+void PrefixAttacher(std::ostream& s, const LogMessage& m, void* data) {
// Assert that `data` contains the expected contents before producing the
// prefix (otherwise causing the tests to fail):
if (data == nullptr || *static_cast<string*>(data) != "good data") {
return;
}
- s << l.severity[0] << setw(4) << 1900 + l.time.year() << setw(2)
- << 1 + l.time.month() << setw(2) << l.time.day() << ' ' << setw(2)
- << l.time.hour() << ':' << setw(2) << l.time.min() << ':' << setw(2)
- << l.time.sec() << "." << setw(6) << l.time.usec() << ' ' << setfill(' ')
- << setw(5) << l.thread_id << setfill('0') << ' ' << l.filename << ':'
- << l.line_number << "]";
+ s << GetLogSeverityName(m.severity())[0] << setw(4) << 1900 + m.time().year()
+ << setw(2) << 1 + m.time().month() << setw(2) << m.time().day() << ' '
+ << setw(2) << m.time().hour() << ':' << setw(2) << m.time().min() << ':'
+ << setw(2) << m.time().sec() << "." << setw(6) << m.time().usec() << ' '
+ << setfill(' ') << setw(5) << m.thread_id() << setfill('0') << ' '
+ << m.basename() << ':' << m.line() << "]";
}
+} // namespace
+
int main(int argc, char** argv) {
FLAGS_colorlogtostderr = false;
FLAGS_timestamp_in_logfile_name = true;
@@ -222,8 +226,8 @@
// Setting a custom prefix generator (it will use the default format so that
// the golden outputs can be reused):
string prefix_attacher_data = "good data";
- InitGoogleLogging(argv[0], &PrefixAttacher,
- static_cast<void*>(&prefix_attacher_data));
+ InitGoogleLogging(argv[0]);
+ InstallPrefixFormatter(&PrefixAttacher, &prefix_attacher_data);
EXPECT_TRUE(IsGoogleLoggingInitialized());
