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Diffstat (limited to 'cpp/src/qpid/asyncStore/jrnl2/JournalRunState.h')
| -rw-r--r-- | cpp/src/qpid/asyncStore/jrnl2/JournalRunState.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/cpp/src/qpid/asyncStore/jrnl2/JournalRunState.h b/cpp/src/qpid/asyncStore/jrnl2/JournalRunState.h new file mode 100644 index 0000000000..85141d8e18 --- /dev/null +++ b/cpp/src/qpid/asyncStore/jrnl2/JournalRunState.h @@ -0,0 +1,174 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ + +/** + * \file JournalRunState.h + */ + +#ifndef qpid_asyncStore_jrnl2_JournalRunState_h_ +#define qpid_asyncStore_jrnl2_JournalRunState_h_ + +#include "State.h" + +namespace qpid { +namespace asyncStore { +namespace jrnl2 { + +/** + * \brief Enumeration of valid AsyncJournal states. + */ +typedef enum { + JS_NONE = 0, ///< Not initialized, not capable of running (This is the default/reset state). + JS_RECOVERING_PHASE_1, ///< Recovery phase 1 (analyzing and restoring AsyncJournal state from journal files). + JS_RECOVERING_PHASE_2, ///< Recovery phase 2 (recovering message content and restoring messages in the broker). + JS_INITIALIZING, ///< Initialization of a new journal, including preparing journal files. + JS_RUNNING, ///< Initialization or recovery complete, journal running and accepting content. + JS_STOPPING, ///< Journal stopping. No new requests for service accepted, waiting for internal state to become consistent. + JS_STOPPED ///< Journal stopped. No new requests for service accepted, store in a consistent state. +} journalState_t; + +/** + * \brief State manager for the state of an AsyncJournal instance. + * + * The AsyncJournal has the following states and transitions: + * \dot + * digraph journalState_t { + * node [fontname=Helvetica, fontsize=8]; + * JS_NONE [URL="\ref JS_NONE"] + * JS_RECOVERING_PHASE_1 [URL="\ref JS_RECOVERING_PHASE_1"] + * JS_RECOVERING_PHASE_2 [URL="\ref JS_RECOVERING_PHASE_2"] + * JS_INITIALIZING [URL="\ref JS_INITIALIZING"] + * JS_RUNNING [URL="\ref JS_RUNNING"] + * JS_STOPPING [URL="\ref JS_STOPPING"] + * JS_STOPPED [URL="\ref JS_STOPPED"] + * + * edge [fontname=Helvetica, fontsize=8] + * JS_NONE->JS_INITIALIZING [label="initialize()" URL="\ref qpid::jrnl2::JournalRunState::initialize()"] + * JS_INITIALIZING->JS_RUNNING [label="run()" URL="\ref qpid::jrnl2::JournalRunState::run()"] + * JS_NONE->JS_RECOVERING_PHASE_1 [label="recoverPhase1()" URL="\ref qpid::jrnl2::JournalRunState::recoverPhase1()"] + * JS_RECOVERING_PHASE_1->JS_RECOVERING_PHASE_2 [label="recoverPhase2()" URL="\ref qpid::jrnl2::JournalRunState::recoverPhase2()"] + * JS_RECOVERING_PHASE_2->JS_RUNNING [label="run()" URL="\ref qpid::jrnl2::JournalRunState::run()"] + * JS_RUNNING->JS_STOPPING [label="stop()" URL="\ref qpid::jrnl2::JournalRunState::stop()"] + * JS_STOPPING->JS_STOPPED [label="stopped()" URL="\ref qpid::jrnl2::JournalRunState::stopped()"] + * } + * \enddot + */ +class JournalRunState : public State<journalState_t> +{ +public: + /** + * \brief Default constructor, setting internal state to JS_NONE. + */ + JournalRunState(); + + /** + * \brief Constructor allowing the internal state to be preset to any valid value of journalState_t. + * + * \param s State value to which the internal state of this new instance should be initialized. + */ + JournalRunState(const journalState_t s); + + /** + * \brief Copy constructor. + * \param s Instance from which this new instance state should be copied. + */ + JournalRunState(const JournalRunState& s); + + /** + * \brief Virtual destructor + */ + virtual ~JournalRunState(); + + // State change functions + + /** + * \brief Changes the journal state from JS_NONE to JS_INITIALIZING. + * + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_INITIALIZING according to the state machine semantics. + */ + void initialize(); + + /** + * \brief Changes the journal state from JS_NONE to JS_RECOVERING_PHASE_1. + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_RECOVERING_PHASE_1 according to the state machine semantics. + */ + void recoverPhase1(); + + /** + * \brief Changes the journal state from JS_RECOVERING_PHASE_1 to JS_RECOVERING_PHASE_2. + * + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_RECOVERING_PHASE_2 according to the state machine semantics. + */ + void recoverPhase2(); + + /** + * \brief Changes the journal state from JS_INITIALIZING or JS_RECOVERING_PHASE_2 to JS_RUNNING. + * + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_RUNNING according to the state machine semantics. + */ + void run(); + + /** + * \brief Changes the journal state from JS_RUNNING to JS_STOPPING. + * + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_STOPPING according to the state machine semantics. + */ + void stop(); + + /** + * \brief Changes the journal state from JS_STOPPING to JS_STOPPED. + * + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to JS_STOPPED according to the state machine semantics. + */ + void stopped(); + + /** + * \brief Get the current state in a string form. + * + * \returns String representation of internal state m_state as returned by static function s_toStr(). + */ + const char* getAsStr() const; + + /** + * \brief Static helper function to convert a numeric journalState_t type to a string representation. + */ + static const char* s_toStr(const journalState_t s); + +protected: + /** + * \brief Set (or change) the value of m_state. This function implements the state machine checks for + * legal state change transitions, and throw an exception if an illegal state transition is requested. + * + * \param s State to which this machine should be changed. + * \throws JournalException with JERR_ILLEGALJRNLSTATECHANGE if current state makes it illegal to change + * to the requested state \a s. + */ + void set(const journalState_t s); + +}; + +}}} // namespace qpid::asyncStore::jrnl2 + +#endif // qpid_asyncStore_jrnl2_JournalRunState_h_ |