ceph/src/zstd/contrib/pzstd/Logging.h

   1 /**
   2  * Copyright (c) 2016-present, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under the BSD-style license found in the
   6  * LICENSE file in the root directory of this source tree. An additional grant
   7  * of patent rights can be found in the PATENTS file in the same directory.
   8  */
   9 #pragma once
  10
  11 #include <cstdio>
  12 #include <mutex>
  13
  14 namespace pzstd {
  15
  16 constexpr int ERROR = 1;
  17 constexpr int INFO = 2;
  18 constexpr int DEBUG = 3;
  19 constexpr int VERBOSE = 4;
  20
  21 class Logger {
  22   std::mutex mutex_;
  23   FILE* out_;
  24   const int level_;
  25
  26   using Clock = std::chrono::system_clock;
  27   Clock::time_point lastUpdate_;
  28   std::chrono::milliseconds refreshRate_;
  29
  30  public:
  31   explicit Logger(int level, FILE* out = stderr)
  32       : out_(out), level_(level), lastUpdate_(Clock::now()),
  33         refreshRate_(150) {}
  34
  35
  36   bool logsAt(int level) {
  37     return level <= level_;
  38   }
  39
  40   template <typename... Args>
  41   void operator()(int level, const char *fmt, Args... args) {
  42     if (level > level_) {
  43       return;
  44     }
  45     std::lock_guard<std::mutex> lock(mutex_);
  46     std::fprintf(out_, fmt, args...);
  47   }
  48
  49   template <typename... Args>
  50   void update(int level, const char *fmt, Args... args) {
  51     if (level > level_) {
  52       return;
  53     }
  54     std::lock_guard<std::mutex> lock(mutex_);
  55     auto now = Clock::now();
  56     if (now - lastUpdate_ > refreshRate_) {
  57       lastUpdate_ = now;
  58       std::fprintf(out_, "\r");
  59       std::fprintf(out_, fmt, args...);
  60     }
  61   }
  62
  63   void clear(int level) {
  64     if (level > level_) {
  65       return;
  66     }
  67     std::lock_guard<std::mutex> lock(mutex_);
  68     std::fprintf(out_, "\r%79s\r", "");
  69   }
  70 };
  71
  72 }