ceph/src/common/dout.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2010 Sage Weil <sage@newdream.net>
   7  * Copyright (C) 2010 Dreamhost
   8  *
   9  * This is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License version 2.1, as published by the Free Software
  12  * Foundation.  See file COPYING.
  13  *
  14  */
  15
  16 #ifndef CEPH_DOUT_H
  17 #define CEPH_DOUT_H
  18
  19 #include "global/global_context.h"
  20 #include "common/config.h"
  21 #include "common/likely.h"
  22 #include "common/Clock.h"
  23 #include "log/Log.h"
  24 #include "include/assert.h"
  25
  26 #include <iostream>
  27 #include <pthread.h>
  28 #include <streambuf>
  29 #include <sstream>
  30
  31 extern void dout_emergency(const char * const str);
  32 extern void dout_emergency(const std::string &str);
  33
  34 // intentionally conflict with endl
  35 class _bad_endl_use_dendl_t { public: _bad_endl_use_dendl_t(int) {} };
  36 static const _bad_endl_use_dendl_t endl = 0;
  37 inline std::ostream& operator<<(std::ostream& out, _bad_endl_use_dendl_t) {
  38   assert(0 && "you are using the wrong endl.. use std::endl or dendl");
  39   return out;
  40 }
  41
  42 class DoutPrefixProvider {
  43 public:
  44   virtual string gen_prefix() const = 0;
  45   virtual CephContext *get_cct() const = 0;
  46   virtual unsigned get_subsys() const = 0;
  47   virtual ~DoutPrefixProvider() {}
  48 };
  49
  50 // generic macros
  51 #define dout_prefix *_dout
  52
  53 #define dout_impl(cct, sub, v)                                          \
  54   do {                                                                  \
  55   if (cct->_conf->subsys.should_gather(sub, v)) {                       \
  56     if (0) {                                                            \
  57       char __array[((v >= -1) && (v <= 200)) ? 0 : -1] __attribute__((unused)); \
  58     }                                                                   \
  59     static size_t _log_exp_length=80; \
  60     ceph::logging::Entry *_dout_e = cct->_log->create_entry(v, sub, &_log_exp_length);  \
  61     ostream _dout_os(&_dout_e->m_streambuf);                            \
  62     CephContext *_dout_cct = cct;                                       \
  63     std::ostream* _dout = &_dout_os;
  64
  65 #define lsubdout(cct, sub, v)  dout_impl(cct, ceph_subsys_##sub, v) dout_prefix
  66 #define ldout(cct, v)  dout_impl(cct, dout_subsys, v) dout_prefix
  67 #define lderr(cct) dout_impl(cct, ceph_subsys_, -1) dout_prefix
  68
  69 #define ldpp_dout(dpp, v) if (dpp) dout_impl(dpp->get_cct(), dpp->get_subsys(), v) (*_dout << dpp->gen_prefix())
  70
  71 #define lgeneric_subdout(cct, sub, v) dout_impl(cct, ceph_subsys_##sub, v) *_dout
  72 #define lgeneric_dout(cct, v) dout_impl(cct, ceph_subsys_, v) *_dout
  73 #define lgeneric_derr(cct) dout_impl(cct, ceph_subsys_, -1) *_dout
  74
  75 #define ldlog_p1(cct, sub, lvl)                 \
  76   (cct->_conf->subsys.should_gather((sub), (lvl)))
  77
  78 // NOTE: depend on magic value in _ASSERT_H so that we detect when
  79 // /usr/include/assert.h clobbers our fancier version.
  80 #define dendl_impl std::flush;                          \
  81   _ASSERT_H->_log->submit_entry(_dout_e);               \
  82     }                                           \
  83   } while (0)
  84
  85 #define dendl dendl_impl
  86
  87 #endif