components/pfs_component/pfs_example

/* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. 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 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, 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */ #include <cstring> #include <my_dbug.h> #include "pfs_example_continent.h" /* Global share pointer for a table */ PFS_engine_table_share_proxy continent_st_share; native_mutex_t LOCK_continent_records_array; /* Total number of rows in table. */ unsigned int continent_rows_in_table = 0; /* Next available index for new record to be stored in global record array. */ unsigned int continent_next_available_index = 0; Continent_record continent_records_array[CONTINENT_MAX_ROWS] = { "", 0, false}; /** * Instantiate Continent_Table_Handle at plugin code when corresponding table * in performance schema is opened. */ PSI_table_handle * continent_open_table(PSI_pos **pos) { Continent_Table_Handle *temp = new Continent_Table_Handle(); temp->current_row.name_length = 0; *pos = (PSI_pos *)(&temp->m_pos); return (PSI_table_handle *)temp; } /** * Destroy the Continent_Table_Handle at plugin code when corresponding table * in performance schema is closed. */ void continent_close_table(PSI_table_handle *handle) { Continent_Table_Handle *temp = (Continent_Table_Handle *)handle; delete temp; } /* Copy record from source to destination */ static void copy_record(Continent_record *dest, Continent_record *source) { dest->name_length = source->name_length; strncpy(dest->name, source->name, dest->name_length); dest->m_exist = source->m_exist; } /* Define implementation of PFS_engine_table_proxy. */ int continent_rnd_next(PSI_table_handle *handle) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; for (h->m_pos.set_at(&h->m_next_pos); h->m_pos.has_more(); h->m_pos.next()) { Continent_record *record = &continent_records_array[h->m_pos.get_index()]; if (record->m_exist) { /* Make the current row from records_array buffer */ copy_record(&h->current_row, record); h->m_next_pos.set_after(&h->m_pos); return 0; } } return PFS_HA_ERR_END_OF_FILE; } int continent_rnd_init(PSI_table_handle *, bool) { return 0; } /* Set position of a cursor on a specific index */ int continent_rnd_pos(PSI_table_handle *handle) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; Continent_record *record = &continent_records_array[h->m_pos.get_index()]; if (record->m_exist) { /* Make the current row from records_array buffer */ copy_record(&h->current_row, record); } return 0; } /* Initialize the table index */ int continent_index_init(PSI_table_handle *handle, unsigned int idx, bool, PSI_index_handle **index) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; /* If there are multiple indexes, initialize based on the idx provided */ switch (idx) { case 0: { h->index_num = idx; Continent_index_by_name *i = &h->m_index; /* Initialize first key in index */ i->m_name.m_name = "NAME"; i->m_name.m_find_flags = 0; i->m_name.m_value_buffer = i->m_name_buffer; i->m_name.m_value_buffer_capacity = sizeof(i->m_name_buffer); *index = (PSI_index_handle *)i; } break; default: DBUG_ASSERT(0); break; } return 0; } /* For each key in index, read value specified in query */ int continent_index_read(PSI_index_handle *index, PSI_key_reader *reader, unsigned int idx, int find_flag) { switch (idx) { case 0: { Continent_index_by_name *i = (Continent_index_by_name *)index; /* Read all keys on index one by one */ mysql_service_pfs_plugin_table->read_key_string(reader, &i->m_name, find_flag); } break; default: DBUG_ASSERT(0); break; } return 0; } /* Read the next indexed value */ int continent_index_next(PSI_table_handle *handle) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; Continent_index *i = NULL; switch (h->index_num) { case 0: i = (Continent_index_by_name *)&h->m_index; break; default: DBUG_ASSERT(0); break; } for (h->m_pos.set_at(&h->m_next_pos); h->m_pos.has_more(); h->m_pos.next()) { Continent_record *record = &continent_records_array[h->m_pos.get_index()]; if (record->m_exist) { if (i->match(record)) { copy_record(&h->current_row, record); h->m_next_pos.set_after(&h->m_pos); return 0; } } } return PFS_HA_ERR_END_OF_FILE; } /* Reset cursor position */ void continent_reset_position(PSI_table_handle *handle) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; h->m_pos.reset(); h->m_next_pos.reset(); return; } /* Read current row from the current_row and display them in the table */ int continent_read_column_value(PSI_table_handle *handle, PSI_field *field, unsigned int index) { Continent_Table_Handle *h = (Continent_Table_Handle *)handle; switch (index) { case 0: /* NAME */ mysql_service_pfs_plugin_table->set_field_char_utf8( field, h->current_row.name, h->current_row.name_length); break; default: /* We should never reach here */ DBUG_ASSERT(0); break; } return 0; } /* As this is a readonly table, we can't use continent_write_row_values funcion, so use this function to populate rows from component code. */ int write_rows_from_component(Continent_Table_Handle *handle) { if (!handle) return 1; native_mutex_lock(&LOCK_continent_records_array); /* If there is no more space for inserting a record, return */ if (continent_rows_in_table >= CONTINENT_MAX_ROWS) { native_mutex_unlock(&LOCK_continent_records_array); return 1; } copy_record(&continent_records_array[continent_next_available_index], &handle->current_row); continent_rows_in_table++; /* set next available index */ if (continent_rows_in_table < CONTINENT_MAX_ROWS) { int i = (continent_next_available_index + 1) % CONTINENT_MAX_ROWS; int itr_count = 0; while(itr_count < CONTINENT_MAX_ROWS) { if (continent_records_array[i].m_exist == false) { continent_next_available_index = i; break; } i = (i+1) % CONTINENT_MAX_ROWS; itr_count++; } } native_mutex_unlock(&LOCK_continent_records_array); return 0; } unsigned long long continent_get_row_count(void) { return continent_rows_in_table; } void init_continent_share(PFS_engine_table_share_proxy *share) { /* Instantiate and initialize PFS_engine_table_share_proxy */ share->m_table_name = "pfs_example_continent"; share->m_table_name_length = 21; share->m_table_definition = "NAME char(20) not null, PRIMARY KEY(NAME)"; share->m_ref_length = sizeof(Continent_POS); share->m_acl = READONLY; share->get_row_count = continent_get_row_count; share->delete_all_rows = NULL; /* READONLY TABLE */ /* Initialize PFS_engine_table_proxy */ share->m_proxy_engine_table = {continent_rnd_next, continent_rnd_init, continent_rnd_pos, continent_index_init, continent_index_read, continent_index_next, continent_read_column_value, continent_reset_position, NULL, /* READONLY TABLE */ NULL, /* READONLY TABLE */ NULL, /* READONLY TABLE */ NULL, /* READONLY TABLE */ NULL, /* READONLY TABLE */ continent_open_table, continent_close_table}; }

components/pfs_component/pfs_example_continent.cc (225 lines of code) (raw):