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Diffstat (limited to 'src/common/dout.h')
| -rw-r--r-- | src/common/dout.h | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/src/common/dout.h b/src/common/dout.h new file mode 100644 index 000000000..a1375fbb9 --- /dev/null +++ b/src/common/dout.h @@ -0,0 +1,198 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab +/* + * Ceph - scalable distributed file system + * + * Copyright (C) 2004-2010 Sage Weil <sage@newdream.net> + * Copyright (C) 2010 Dreamhost + * + * This is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1, as published by the Free Software + * Foundation. See file COPYING. + * + */ + +#ifndef CEPH_DOUT_H +#define CEPH_DOUT_H + +#include <type_traits> + +#include "include/ceph_assert.h" +#include "include/common_fwd.h" +#if defined(WITH_SEASTAR) && !defined(WITH_ALIEN) +#include <seastar/util/log.hh> +#include "crimson/common/log.h" +#include "crimson/common/config_proxy.h" +#else +#include "global/global_context.h" +#include "common/ceph_context.h" +#include "common/config.h" +#include "common/likely.h" +#include "common/Clock.h" +#include "log/Log.h" +#endif + +extern void dout_emergency(const char * const str); +extern void dout_emergency(const std::string &str); + +// intentionally conflict with endl +class _bad_endl_use_dendl_t { public: _bad_endl_use_dendl_t(int) {} }; +static const _bad_endl_use_dendl_t endl = 0; +inline std::ostream& operator<<(std::ostream& out, _bad_endl_use_dendl_t) { + ceph_abort_msg("you are using the wrong endl.. use std::endl or dendl"); + return out; +} + +class DoutPrefixProvider { +public: + virtual std::ostream& gen_prefix(std::ostream& out) const = 0; + virtual CephContext *get_cct() const = 0; + virtual unsigned get_subsys() const = 0; + virtual ~DoutPrefixProvider() {} +}; + +// a prefix provider with empty prefix +class NoDoutPrefix : public DoutPrefixProvider { + CephContext *const cct; + const unsigned subsys; + public: + NoDoutPrefix(CephContext *cct, unsigned subsys) : cct(cct), subsys(subsys) {} + + std::ostream& gen_prefix(std::ostream& out) const override { return out; } + CephContext *get_cct() const override { return cct; } + unsigned get_subsys() const override { return subsys; } +}; + +// a prefix provider with static (const char*) prefix +class DoutPrefix : public NoDoutPrefix { + const char *const prefix; + public: + DoutPrefix(CephContext *cct, unsigned subsys, const char *prefix) + : NoDoutPrefix(cct, subsys), prefix(prefix) {} + + std::ostream& gen_prefix(std::ostream& out) const override { + return out << prefix; + } +}; + +// a prefix provider that composes itself on top of another +class DoutPrefixPipe : public DoutPrefixProvider { + const DoutPrefixProvider& dpp; + public: + DoutPrefixPipe(const DoutPrefixProvider& dpp) : dpp(dpp) {} + + std::ostream& gen_prefix(std::ostream& out) const override final { + dpp.gen_prefix(out); + add_prefix(out); + return out; + } + CephContext *get_cct() const override { return dpp.get_cct(); } + unsigned get_subsys() const override { return dpp.get_subsys(); } + + virtual void add_prefix(std::ostream& out) const = 0; +}; + +// helpers +namespace ceph::dout { + +template<typename T> +struct dynamic_marker_t { + T value; + // constexpr ctor isn't needed as it's an aggregate type + constexpr operator T() const { return value; } +}; + +template<typename T> +constexpr dynamic_marker_t<T> need_dynamic(T&& t) { + return dynamic_marker_t<T>{ std::forward<T>(t) }; +} + +template<typename T> +struct is_dynamic : public std::false_type {}; + +template<typename T> +struct is_dynamic<dynamic_marker_t<T>> : public std::true_type {}; + +} // ceph::dout + +// generic macros +#define dout_prefix *_dout + +#if defined(WITH_SEASTAR) && !defined(WITH_ALIEN) +#define dout_impl(cct, sub, v) \ + do { \ + if (crimson::common::local_conf()->subsys.should_gather(sub, v)) { \ + seastar::logger& _logger = crimson::get_logger(sub); \ + const auto _lv = v; \ + std::ostringstream _out; \ + std::ostream* _dout = &_out; +#define dendl_impl \ + ""; \ + _logger.log(crimson::to_log_level(_lv), \ + "{}", _out.str().c_str()); \ + } \ + } while (0) +#elif defined(WITH_SEASTAR) && defined(WITH_ALIEN) +#define dout_impl(cct, sub, v) \ + do { \ + if (0) { \ + ceph::logging::MutableEntry _dout_e(v, sub); \ + std::ostream* _dout = &_dout_e.get_ostream(); + +#define dendl_impl std::flush; \ + } \ + } while (0) +#else +#define dout_impl(cct, sub, v) \ + do { \ + const bool should_gather = [&](const auto cctX) { \ + if constexpr (ceph::dout::is_dynamic<decltype(sub)>::value || \ + ceph::dout::is_dynamic<decltype(v)>::value) { \ + return cctX->_conf->subsys.should_gather(sub, v); \ + } else { \ + /* The parentheses are **essential** because commas in angle \ + * brackets are NOT ignored on macro expansion! A language's \ + * limitation, sorry. */ \ + return (cctX->_conf->subsys.template should_gather<sub, v>()); \ + } \ + }(cct); \ + \ + if (should_gather) { \ + ceph::logging::MutableEntry _dout_e(v, sub); \ + static_assert(std::is_convertible<decltype(&*cct), \ + CephContext* >::value, \ + "provided cct must be compatible with CephContext*"); \ + auto _dout_cct = cct; \ + std::ostream* _dout = &_dout_e.get_ostream(); + +#define dendl_impl std::flush; \ + _dout_cct->_log->submit_entry(std::move(_dout_e)); \ + } \ + } while (0) +#endif // WITH_SEASTAR + +#define lsubdout(cct, sub, v) dout_impl(cct, ceph_subsys_##sub, v) dout_prefix +#define ldout(cct, v) dout_impl(cct, dout_subsys, v) dout_prefix +#define lderr(cct) dout_impl(cct, ceph_subsys_, -1) dout_prefix + +#define ldpp_subdout(dpp, sub, v) \ + if (decltype(auto) pdpp = (dpp); pdpp) /* workaround -Wnonnull-compare for 'this' */ \ + dout_impl(pdpp->get_cct(), ceph_subsys_##sub, v) \ + pdpp->gen_prefix(*_dout) + +#define ldpp_dout(dpp, v) \ + if (decltype(auto) pdpp = (dpp); pdpp) /* workaround -Wnonnull-compare for 'this' */ \ + dout_impl(pdpp->get_cct(), ceph::dout::need_dynamic(pdpp->get_subsys()), v) \ + pdpp->gen_prefix(*_dout) + +#define lgeneric_subdout(cct, sub, v) dout_impl(cct, ceph_subsys_##sub, v) *_dout +#define lgeneric_dout(cct, v) dout_impl(cct, ceph_subsys_, v) *_dout +#define lgeneric_derr(cct) dout_impl(cct, ceph_subsys_, -1) *_dout + +#define ldlog_p1(cct, sub, lvl) \ + (cct->_conf->subsys.should_gather((sub), (lvl))) + +#define dendl dendl_impl + +#endif |