/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
// vim: ft=cpp:expandtab:ts=8:sw=4:softtabstop=4:
#ident "$Id$"
/*======
This file is part of PerconaFT.


Copyright (c) 2006, 2015, Percona and/or its affiliates. All rights reserved.

    PerconaFT is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2,
    as published by the Free Software Foundation.

    PerconaFT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with PerconaFT.  If not, see <http://www.gnu.org/licenses/>.

----------------------------------------

    PerconaFT is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License, version 3,
    as published by the Free Software Foundation.

    PerconaFT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with PerconaFT.  If not, see <http://www.gnu.org/licenses/>.
======= */

#ident "Copyright (c) 2006, 2015, Percona and/or its affiliates. All rights reserved."

#include "ft/logger/log-internal.h"
#include "ft/txn/rollback-apply.h"

static void poll_txn_progress_function(TOKUTXN txn, uint8_t is_commit, uint8_t stall_for_checkpoint) {
    if (txn->progress_poll_fun) {
        TOKU_TXN_PROGRESS_S progress = {
            .entries_total     = txn->roll_info.num_rollentries,
            .entries_processed = txn->roll_info.num_rollentries_processed,
            .is_commit = is_commit,
            .stalled_on_checkpoint = stall_for_checkpoint};
        txn->progress_poll_fun(&progress, txn->progress_poll_fun_extra);
    }
}

int toku_commit_rollback_item (TOKUTXN txn, struct roll_entry *item, LSN lsn) {
    int r=0;
    rolltype_dispatch_assign(item, toku_commit_, r, txn, lsn);
    txn->roll_info.num_rollentries_processed++;
    if (txn->roll_info.num_rollentries_processed % 1024 == 0) {
        poll_txn_progress_function(txn, true, false);
    }
    return r;
}

int toku_abort_rollback_item (TOKUTXN txn, struct roll_entry *item, LSN lsn) {
    int r=0;
    rolltype_dispatch_assign(item, toku_rollback_, r, txn, lsn);
    txn->roll_info.num_rollentries_processed++;
    if (txn->roll_info.num_rollentries_processed % 1024 == 0) {
        poll_txn_progress_function(txn, false, false);
    }
    return r;
}

int note_ft_used_in_txns_parent(const FT &ft, uint32_t UU(index), TOKUTXN const child);
int note_ft_used_in_txns_parent(const FT &ft, uint32_t UU(index), TOKUTXN const child) {
    TOKUTXN parent = child->parent;
    toku_txn_maybe_note_ft(parent, ft);
    return 0;
}

static int apply_txn(TOKUTXN txn, LSN lsn, apply_rollback_item func) {
    int r = 0;
    // do the commit/abort calls and free everything
    // we do the commit/abort calls in reverse order too.
    struct roll_entry *item;
    //printf("%s:%d abort\n", __FILE__, __LINE__);

    BLOCKNUM next_log      = ROLLBACK_NONE;

    bool is_current = false;
    if (txn_has_current_rollback_log(txn)) {
        next_log      = txn->roll_info.current_rollback;
        is_current = true;
    }
    else if (txn_has_spilled_rollback_logs(txn)) {
        next_log      = txn->roll_info.spilled_rollback_tail;
    }

    uint64_t last_sequence = txn->roll_info.num_rollback_nodes;
    bool found_head = false;
    while (next_log.b != ROLLBACK_NONE.b) {
        ROLLBACK_LOG_NODE log;
        //pin log
        toku_get_and_pin_rollback_log(txn, next_log, &log);
        toku_rollback_verify_contents(log, txn->txnid, last_sequence - 1);

        toku_maybe_prefetch_previous_rollback_log(txn, log);

        last_sequence = log->sequence;
        if (func) {
            while ((item=log->newest_logentry)) {
                log->newest_logentry = item->prev;
                r = func(txn, item, lsn);
                if (r!=0) return r;
            }
        }
        if (next_log.b == txn->roll_info.spilled_rollback_head.b) {
            assert(!found_head);
            found_head = true;
            assert(log->sequence == 0);
        }
        next_log      = log->previous;
        {
            //Clean up transaction structure to prevent
            //toku_txn_close from double-freeing
            if (is_current) {
                txn->roll_info.current_rollback      = ROLLBACK_NONE;
                is_current = false;
            }
            else {
                txn->roll_info.spilled_rollback_tail      = next_log;
            }
            if (found_head) {
                assert(next_log.b == ROLLBACK_NONE.b);
                txn->roll_info.spilled_rollback_head      = next_log;
            }
        }
        bool give_back = false;
        // each txn tries to give back at most one rollback log node
        // to the cache.
        if (next_log.b == ROLLBACK_NONE.b) {
            give_back = txn->logger->rollback_cache.give_rollback_log_node(
                txn,
                log
                );
        }
        if (!give_back) {
            toku_rollback_log_unpin_and_remove(txn, log);
        }
    }
    return r;
}

//Commit each entry in the rollback log.
//If the transaction has a parent, it just promotes its information to its parent.
int toku_rollback_commit(TOKUTXN txn, LSN lsn) {
    int r=0;
    if (txn->parent!=0) {
        // First we must put a rollinclude entry into the parent if we spilled

        if (txn_has_spilled_rollback_logs(txn)) {
            uint64_t num_nodes = txn->roll_info.num_rollback_nodes;
            if (txn_has_current_rollback_log(txn)) {
                num_nodes--; //Don't count the in-progress rollback log.
            }
            toku_logger_save_rollback_rollinclude(txn->parent, txn->txnid, num_nodes,
                                                      txn->roll_info.spilled_rollback_head,
                                                      txn->roll_info.spilled_rollback_tail);
            //Remove ownership from child.
            txn->roll_info.spilled_rollback_head      = ROLLBACK_NONE; 
            txn->roll_info.spilled_rollback_tail      = ROLLBACK_NONE; 
        }
        // if we're committing a child rollback, put its entries into the parent
        // by pinning both child and parent and then linking the child log entry
        // list to the end of the parent log entry list.
        if (txn_has_current_rollback_log(txn)) {
            //Pin parent log
            toku_txn_lock(txn->parent);
            ROLLBACK_LOG_NODE parent_log;
            toku_get_and_pin_rollback_log_for_new_entry(txn->parent, &parent_log);

            //Pin child log
            ROLLBACK_LOG_NODE child_log;
            toku_get_and_pin_rollback_log(txn, txn->roll_info.current_rollback, &child_log);
            toku_rollback_verify_contents(child_log, txn->txnid, txn->roll_info.num_rollback_nodes - 1);

            // Append the list to the front of the parent.
            if (child_log->oldest_logentry) {
                // There are some entries, so link them in.
                parent_log->dirty = true;
                child_log->oldest_logentry->prev = parent_log->newest_logentry;
                if (!parent_log->oldest_logentry) {
                    parent_log->oldest_logentry = child_log->oldest_logentry;
                }
                parent_log->newest_logentry = child_log->newest_logentry;
                parent_log->rollentry_resident_bytecount += child_log->rollentry_resident_bytecount;
                txn->parent->roll_info.rollentry_raw_count         += txn->roll_info.rollentry_raw_count;
                child_log->rollentry_resident_bytecount = 0;
            }
            if (parent_log->oldest_logentry==NULL) {
                parent_log->oldest_logentry = child_log->oldest_logentry;
            }
            child_log->newest_logentry = child_log->oldest_logentry = 0;
            // Put all the memarena data into the parent.
            if (child_log->rollentry_arena.total_size_in_use() > 0) {
                // If there are no bytes to move, then just leave things alone, and let the memory be reclaimed on txn is closed.
                child_log->rollentry_arena.move_memory(&parent_log->rollentry_arena);
            }
            // each txn tries to give back at most one rollback log node
            // to the cache. All other rollback log nodes for this child
            // transaction are included in the parent's rollback log,
            // so this is the only node we can give back to the cache
            bool give_back = txn->logger->rollback_cache.give_rollback_log_node(
                txn,
                child_log
                );
            if (!give_back) {
                toku_rollback_log_unpin_and_remove(txn, child_log);
            }
            txn->roll_info.current_rollback = ROLLBACK_NONE;

            toku_maybe_spill_rollbacks(txn->parent, parent_log);
            toku_rollback_log_unpin(txn->parent, parent_log);
            assert(r == 0);
            toku_txn_unlock(txn->parent);
        }

        // Note the open FTs, the omts must be merged
        r = txn->open_fts.iterate<struct tokutxn, note_ft_used_in_txns_parent>(txn);
        assert(r==0);

        //If this transaction needs an fsync (if it commits)
        //save that in the parent.  Since the commit really happens in the root txn.
        txn->parent->force_fsync_on_commit |= txn->force_fsync_on_commit;
        txn->parent->roll_info.num_rollentries       += txn->roll_info.num_rollentries;
    } else {
        r = apply_txn(txn, lsn, toku_commit_rollback_item);
        assert(r==0);
    }

    return r;
}

int toku_rollback_abort(TOKUTXN txn, LSN lsn) {
    int r;
    r = apply_txn(txn, lsn, toku_abort_rollback_item);
    assert(r==0);
    return r;
}

int toku_rollback_discard(TOKUTXN txn) {
    txn->roll_info.current_rollback = ROLLBACK_NONE;
    txn->roll_info.spilled_rollback_head = ROLLBACK_NONE;
    txn->roll_info.spilled_rollback_tail = ROLLBACK_NONE;
    return 0;
}

