Files
cpu-check/log.h
2020-05-08 13:33:05 -07:00

143 lines
3.3 KiB
C++

// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef LOG_H_
#define LOG_H_
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <atomic>
#include <iostream>
#include <sstream>
#include <string>
enum LOG_LEVEL {
DEBUG,
INFO,
WARN,
ERROR,
FATAL,
};
// TODO - Flag to filter above a given log level
// TODO
// Make this more efficient. Eg. use:
// LOG_IF_COND(xx) << yy;
// becomes
// for (condvar;COND;) Log(blah).stream() << yy;
#define LOG(X) Log(__FILE__, __LINE__, X).stream()
#define LOG_EVERY_N(X, N) \
static std::atomic<uint64_t> __FILE__##__LINE__##_counter(0); \
Log(__FILE__, __LINE__, X, __FILE__##__LINE__##_counter, N).stream()
#define LOG_EVERY_N_SECS(X, N) \
static std::atomic<int64_t> __FILE__##__LINE__##_lasttime(0); \
Log(__FILE__, __LINE__, X, __FILE__##__LINE__##_lasttime, N).stream()
// TODO
// #define VLOG(x)
static LOG_LEVEL min_log_level = INFO;
class Log {
public:
Log(const char* file, int line, LOG_LEVEL lvl) : lvl_(lvl) {
if (lvl < min_log_level) {
skip_ = true;
return;
}
Init(file, line);
}
// For LOG_EVERY_N:
Log(const char* file, int line, LOG_LEVEL lvl, std::atomic<uint64_t>& cnt,
int N)
: lvl_(lvl) {
if (lvl < min_log_level) {
skip_ = true;
return;
}
if ((++cnt % N) != 0) {
skip_ = true;
return;
}
Init(file, line);
}
// For LOG_EVERY_N_SECS:
Log(const char* file, int line, LOG_LEVEL lvl, std::atomic<int64_t>& t, int N)
: lvl_(lvl) {
if (lvl < min_log_level) {
skip_ = true;
return;
}
int64_t now = time(nullptr);
int64_t last = t;
if (now - last < N || !t.compare_exchange_strong(last, now)) {
skip_ = true;
return;
}
Init(file, line);
}
~Log() {
if (skip_) return;
// You might prefer to direct errors to stderr, e.g.
// (lvl_ < WARN ? std::cout : std::cerr) << os_.str();
std::cout << os_.str() << std::endl;
if (lvl_ == FATAL) {
abort();
}
}
std::ostream& stream() { return os_; }
std::ostream& operator<<(const std::string& s) {
if (skip_) return os_;
return os_ << s;
}
private:
void Init(const char* file, int line) {
static const char l[] = {
'D', 'I', 'W', 'E', 'F',
};
struct timeval tvs;
struct tm tms;
time_t t;
char s[17];
gettimeofday(&tvs, nullptr);
t = tvs.tv_sec;
gmtime_r(&t, &tms);
strftime(s, sizeof(s), "%Y%m%d-%H%M%S.", &tms);
char us[7];
snprintf(us, sizeof(us), "%06ld", (long)tvs.tv_usec);
os_ << l[lvl_] << s << us << ' ' << pthread_self() << " " << file << ':'
<< line << "] ";
}
LOG_LEVEL lvl_;
bool skip_ = false;
std::stringstream os_;
};
#endif // LOG_H_