151 lines
4.7 KiB
C++
151 lines
4.7 KiB
C++
/* Copyright (c) 2020, 2024, Oracle and/or its affiliates.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License, version 2.0,
|
|
as published by the Free Software Foundation.
|
|
|
|
This program is designed to work with certain software (including
|
|
but not limited to OpenSSL) that is licensed under separate terms,
|
|
as designated in a particular file or component or in included license
|
|
documentation. The authors of MySQL hereby grant you an additional
|
|
permission to link the program and your derivative works with the
|
|
separately licensed software that they have either included with
|
|
the program or referenced in the documentation.
|
|
|
|
This program 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, version 2.0, for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
@file storage/perfschema/cursor_by_error_log.cc
|
|
Cursor CURSOR_BY_ERROR_LOG (implementation).
|
|
*/
|
|
|
|
#include "storage/perfschema/cursor_by_error_log.h"
|
|
|
|
#include <stddef.h>
|
|
|
|
#include "storage/perfschema/pfs_buffer_container.h"
|
|
#include "storage/perfschema/pfs_instr.h"
|
|
|
|
// const
|
|
cursor_by_error_log::cursor_by_error_log(const PFS_engine_table_share *share)
|
|
: PFS_engine_table(share, &m_pos), m_pos(), m_next_pos() {}
|
|
|
|
/// Get row-count (by getting the number of events in the ring-buffer)
|
|
ha_rows cursor_by_error_log::get_row_count() {
|
|
return (ha_rows)log_sink_pfs_event_count();
|
|
}
|
|
|
|
/**
|
|
Reset cursor position.
|
|
|
|
We come through here when using a condition
|
|
(rather than just ORDER BY [ASC/DESC]) in SELECT,
|
|
e.g. in the form of ha_perfschema::index_read
|
|
with HA_READ_KEY_EXACT when using =.
|
|
|
|
We don't need a lock here since the reset
|
|
breaks the association with the ring-buffer;
|
|
it will be re-established on the first read-
|
|
style primitive (reading a "row" of payload
|
|
from the ring-buffer, or trying to advance
|
|
to the next entry, either of which will imply
|
|
log_sink_pfs_event_first() at some point).
|
|
*/
|
|
void cursor_by_error_log::reset_position() {
|
|
m_pos.reset();
|
|
m_next_pos.reset();
|
|
}
|
|
|
|
/**
|
|
Read next row (from ring-buffer into table).
|
|
|
|
We come through here when not using an index.
|
|
|
|
@retval HA_ERR_END_OF_FILE failed to locate data, or to create a row from it
|
|
@retval 0 success
|
|
*/
|
|
int cursor_by_error_log::rnd_next() {
|
|
log_sink_pfs_event *row;
|
|
int ret = HA_ERR_END_OF_FILE;
|
|
|
|
log_sink_pfs_read_start(); // obtain read-lock on ring-buffer
|
|
|
|
m_pos.set_at(&m_next_pos); // set current position to next
|
|
|
|
row = m_pos.scan_next(); // get current row and advance index
|
|
|
|
if (row != nullptr) { // if we managed to obtain an event (a "row") ...
|
|
// Set next_position to the successor of the row we just obtained.
|
|
m_next_pos.set_at(&m_pos);
|
|
|
|
// copy event from ring-buffer to table_error_log instance
|
|
ret = make_row(row);
|
|
}
|
|
|
|
log_sink_pfs_read_end(); // release read-lock
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
Random pos. Unused.
|
|
|
|
@retval HA_ERR_RECORD_DELETED failed to locate data/to create a row from it
|
|
@retval 0 success
|
|
*/
|
|
int cursor_by_error_log::rnd_pos(const void *pos) {
|
|
log_sink_pfs_event *row; /* purecov: begin inspected */
|
|
int ret = HA_ERR_RECORD_DELETED;
|
|
|
|
log_sink_pfs_read_start(); // acquire read-lock on ring-buffer.
|
|
|
|
set_position(pos);
|
|
|
|
row = m_pos.get_event(); // obtain event from ring-buffer
|
|
|
|
if (row != nullptr) ret = make_row(row); // fill in SQL row
|
|
|
|
log_sink_pfs_read_end(); // release read-lock.
|
|
|
|
return ret; /* purecov: end */
|
|
}
|
|
|
|
/**
|
|
Go to next entry in index and retrieve the matching error log event.
|
|
|
|
We come through here e.g. for = in the SELECT's condition,
|
|
i.e. HA_READ_KEY_EXACT.
|
|
|
|
@retval HA_ERR_END_OF_FILE failed to locate data, or to create a row from it
|
|
@retval 0 success
|
|
*/
|
|
int cursor_by_error_log::index_next() {
|
|
log_sink_pfs_event *row;
|
|
int ret = HA_ERR_END_OF_FILE;
|
|
|
|
log_sink_pfs_read_start(); // obtain read-lock on ring-buffer
|
|
|
|
m_pos.set_at(&m_next_pos); // set current position to next
|
|
|
|
while ((row = m_pos.scan_next()) != nullptr) { // Get row from ring-buffer
|
|
if (m_opened_index->match(row)) { // If it matches the index-result ...
|
|
if (!make_row(row)) { // - make a copy of the event
|
|
m_next_pos.set_at(&m_pos); // - advance read position
|
|
ret = 0; // - flag success
|
|
break; // We're done.
|
|
}
|
|
}
|
|
}
|
|
|
|
log_sink_pfs_read_end();
|
|
|
|
return ret;
|
|
}
|