/*****************************************************************************

Copyright (c) 2012, 2016, 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, version 2.0,
as published by the Free Software Foundation.

This program is also distributed 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 included with MySQL.

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 Street, Suite 500, Boston, MA 02110-1335 USA

*****************************************************************************/

/**************************************************//**
@file row/row0quiesce.cc
Quiesce a tablespace.

Created 2012-02-08 by Sunny Bains.
*******************************************************/

#include "row0quiesce.h"
#include "row0mysql.h"

#ifdef UNIV_NONINL
#include "row0quiesce.ic"
#endif

#include "ibuf0ibuf.h"
#include "srv0start.h"
#include "trx0purge.h"

/*********************************************************************//**
Write the meta data (index user fields) config file.
@return DB_SUCCESS or error code. */
static	MY_ATTRIBUTE((nonnull, warn_unused_result))
dberr_t
row_quiesce_write_index_fields(
/*===========================*/
	const dict_index_t*	index,	/*!< in: write the meta data for
					this index */
	FILE*			file,	/*!< in: file to write to */
	THD*			thd)	/*!< in/out: session */
{
	byte			row[sizeof(ib_uint32_t) * 2];

	for (ulint i = 0; i < index->n_fields; ++i) {
		byte*			ptr = row;
		const dict_field_t*	field = &index->fields[i];

		mach_write_to_4(ptr, field->prefix_len);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, field->fixed_len);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_9",
				close(fileno(file)););

		if (fwrite(row, 1, sizeof(row), file) != sizeof(row)) {

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing index fields.");

			return(DB_IO_ERROR);
		}

		/* Include the NUL byte in the length. */
		ib_uint32_t	len = static_cast<ib_uint32_t>(strlen(field->name) + 1);
		ut_a(len > 1);

		mach_write_to_4(row, len);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_10",
				close(fileno(file)););

		if (fwrite(row, 1,  sizeof(len), file) != sizeof(len)
		    || fwrite(field->name, 1, len, file) != len) {

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing index column.");

			return(DB_IO_ERROR);
		}
	}

	return(DB_SUCCESS);
}

/*********************************************************************//**
Write the meta data config file index information.
@return DB_SUCCESS or error code. */
static	MY_ATTRIBUTE((nonnull, warn_unused_result))
dberr_t
row_quiesce_write_indexes(
/*======================*/
	const dict_table_t*	table,	/*!< in: write the meta data for
					this table */
	FILE*			file,	/*!< in: file to write to */
	THD*			thd)	/*!< in/out: session */
{
	{
		byte		row[sizeof(ib_uint32_t)];

		/* Write the number of indexes in the table. */
		mach_write_to_4(row, UT_LIST_GET_LEN(table->indexes));

		DBUG_EXECUTE_IF("ib_export_io_write_failure_11",
				close(fileno(file)););

		if (fwrite(row, 1,  sizeof(row), file) != sizeof(row)) {
			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing index count.");

			return(DB_IO_ERROR);
		}
	}

	dberr_t			err = DB_SUCCESS;

	/* Write the index meta data. */
	for (const dict_index_t* index = UT_LIST_GET_FIRST(table->indexes);
	     index != 0 && err == DB_SUCCESS;
	     index = UT_LIST_GET_NEXT(indexes, index)) {

		byte*		ptr;
		byte		row[sizeof(index_id_t)
				    + sizeof(ib_uint32_t) * 8];

		ptr = row;

		ut_ad(sizeof(index_id_t) == 8);
		mach_write_to_8(ptr, index->id);
		ptr += sizeof(index_id_t);

		mach_write_to_4(ptr, index->space);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->page);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->type);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->trx_id_offset);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->n_user_defined_cols);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->n_uniq);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->n_nullable);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, index->n_fields);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_12",
				close(fileno(file)););

		if (fwrite(row, 1, sizeof(row), file) != sizeof(row)) {

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing index meta-data.");

			return(DB_IO_ERROR);
		}

		/* Write the length of the index name.
		NUL byte is included in the length. */
		ib_uint32_t	len = static_cast<ib_uint32_t>(strlen(index->name) + 1);
		ut_a(len > 1);

		mach_write_to_4(row, len);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_1",
				close(fileno(file)););

		if (fwrite(row, 1, sizeof(len), file) != sizeof(len)
		    || fwrite(index->name, 1, len, file) != len) {

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing index name.");

			return(DB_IO_ERROR);
		}

		err = row_quiesce_write_index_fields(index, file, thd);
	}

	return(err);
}

/*********************************************************************//**
Write the meta data (table columns) config file. Serialise the contents of
dict_col_t structure, along with the column name. All fields are serialized
as ib_uint32_t.
@return DB_SUCCESS or error code. */
static	MY_ATTRIBUTE((nonnull, warn_unused_result))
dberr_t
row_quiesce_write_table(
/*====================*/
	const dict_table_t*	table,	/*!< in: write the meta data for
					this table */
	FILE*			file,	/*!< in: file to write to */
	THD*			thd)	/*!< in/out: session */
{
	dict_col_t*		col;
	byte			row[sizeof(ib_uint32_t) * 7];

	col = table->cols;

	for (ulint i = 0; i < table->n_cols; ++i, ++col) {
		byte*		ptr = row;

		mach_write_to_4(ptr, col->prtype);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->mtype);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->len);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->mbminmaxlen);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->ind);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->ord_part);
		ptr += sizeof(ib_uint32_t);

		mach_write_to_4(ptr, col->max_prefix);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_2",
				close(fileno(file)););

		if (fwrite(row, 1,  sizeof(row), file) != sizeof(row)) {
			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing table column data.");

			return(DB_IO_ERROR);
		}

		/* Write out the column name as [len, byte array]. The len
		includes the NUL byte. */
		ib_uint32_t	len;
		const char*	col_name;

		col_name = dict_table_get_col_name(table, dict_col_get_no(col));

		/* Include the NUL byte in the length. */
		len = static_cast<ib_uint32_t>(strlen(col_name) + 1);
		ut_a(len > 1);

		mach_write_to_4(row, len);

		DBUG_EXECUTE_IF("ib_export_io_write_failure_3",
				close(fileno(file)););

		if (fwrite(row, 1,  sizeof(len), file) != sizeof(len)
		    || fwrite(col_name, 1, len, file) != len) {

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno),
				"while writing column name.");

			return(DB_IO_ERROR);
		}
	}

	return(DB_SUCCESS);
}

/*********************************************************************//**
Write the meta data config file header.
@return DB_SUCCESS or error code. */
static	MY_ATTRIBUTE((nonnull, warn_unused_result))
dberr_t
row_quiesce_write_header(
/*=====================*/
	const dict_table_t*	table,	/*!< in: write the meta data for
					this table */
	FILE*			file,	/*!< in: file to write to */
	THD*			thd)	/*!< in/out: session */
{
	byte			value[sizeof(ib_uint32_t)];

	/* Write the meta-data version number. */
	mach_write_to_4(value, IB_EXPORT_CFG_VERSION_V1);

	DBUG_EXECUTE_IF("ib_export_io_write_failure_4", close(fileno(file)););

	if (fwrite(&value, 1,  sizeof(value), file) != sizeof(value)) {
		ib_senderrf(
			thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
			errno, strerror(errno),
			"while writing meta-data version number.");

		return(DB_IO_ERROR);
	}

	/* Write the server hostname. */
	ib_uint32_t		len;
	const char*		hostname = server_get_hostname();

	/* Play it safe and check for NULL. */
	if (hostname == 0) {
		static const char	NullHostname[] = "Hostname unknown";

		ib_logf(IB_LOG_LEVEL_WARN,
			"Unable to determine server hostname.");

		hostname = NullHostname;
	}

	/* The server hostname includes the NUL byte. */
	len = static_cast<ib_uint32_t>(strlen(hostname) + 1);
	mach_write_to_4(value, len);

	DBUG_EXECUTE_IF("ib_export_io_write_failure_5", close(fileno(file)););

	if (fwrite(&value, 1,  sizeof(value), file) != sizeof(value)
	    || fwrite(hostname, 1,  len, file) != len) {

		ib_senderrf(
			thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
			errno, strerror(errno),
			"while writing hostname.");

		return(DB_IO_ERROR);
	}

	/* The table name includes the NUL byte. */
	ut_a(table->name != 0);
	len = static_cast<ib_uint32_t>(strlen(table->name) + 1);

	/* Write the table name. */
	mach_write_to_4(value, len);

	DBUG_EXECUTE_IF("ib_export_io_write_failure_6", close(fileno(file)););

	if (fwrite(&value, 1,  sizeof(value), file) != sizeof(value)
	    || fwrite(table->name, 1,  len, file) != len) {

		ib_senderrf(
			thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
			errno, strerror(errno),
			"while writing table name.");

		return(DB_IO_ERROR);
	}

	byte		row[sizeof(ib_uint32_t) * 3];

	/* Write the next autoinc value. */
	mach_write_to_8(row, table->autoinc);

	DBUG_EXECUTE_IF("ib_export_io_write_failure_7", close(fileno(file)););

	if (fwrite(row, 1,  sizeof(ib_uint64_t), file) != sizeof(ib_uint64_t)) {
		ib_senderrf(
			thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
			errno, strerror(errno),
			"while writing table autoinc value.");

		return(DB_IO_ERROR);
	}

	byte*		ptr = row;

	/* Write the system page size. */
	mach_write_to_4(ptr, UNIV_PAGE_SIZE);
	ptr += sizeof(ib_uint32_t);

	/* Write the table->flags. */
	mach_write_to_4(ptr, table->flags);
	ptr += sizeof(ib_uint32_t);

	/* Write the number of columns in the table. */
	mach_write_to_4(ptr, table->n_cols);

	DBUG_EXECUTE_IF("ib_export_io_write_failure_8", close(fileno(file)););

	if (fwrite(row, 1,  sizeof(row), file) != sizeof(row)) {
		ib_senderrf(
			thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
			errno, strerror(errno),
			"while writing table meta-data.");

		return(DB_IO_ERROR);
	}

	return(DB_SUCCESS);
}

/*********************************************************************//**
Write the table meta data after quiesce.
@return DB_SUCCESS or error code */
static	MY_ATTRIBUTE((nonnull, warn_unused_result))
dberr_t
row_quiesce_write_cfg(
/*==================*/
	dict_table_t*	table,	/*!< in: write the meta data for
					this table */
	THD*			thd)	/*!< in/out: session */
{
	dberr_t			err;
	char			name[OS_FILE_MAX_PATH];

	srv_get_meta_data_filename(table, name, sizeof(name));

	ib_logf(IB_LOG_LEVEL_INFO, "Writing table metadata to '%s'", name);

	FILE*	file = fopen(name, "w+b");

	if (file == NULL) {
		ib_errf(thd, IB_LOG_LEVEL_WARN, ER_CANT_CREATE_FILE,
			 name, errno, strerror(errno));

		err = DB_IO_ERROR;
	} else {
		err = row_quiesce_write_header(table, file, thd);

		if (err == DB_SUCCESS) {
			err = row_quiesce_write_table(table, file, thd);
		}

		if (err == DB_SUCCESS) {
			err = row_quiesce_write_indexes(table, file, thd);
		}

		if (fflush(file) != 0) {

			char	msg[BUFSIZ];

			ut_snprintf(msg, sizeof(msg), "%s flush() failed",
				    name);

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno), msg);
		}

		if (fclose(file) != 0) {
			char	msg[BUFSIZ];

			ut_snprintf(msg, sizeof(msg), "%s flose() failed",
				    name);

			ib_senderrf(
				thd, IB_LOG_LEVEL_WARN, ER_IO_WRITE_ERROR,
				errno, strerror(errno), msg);
		}
	}

	return(err);
}

/*********************************************************************//**
Check whether a table has an FTS index defined on it.
@return true if an FTS index exists on the table */
static
bool
row_quiesce_table_has_fts_index(
/*============================*/
	const dict_table_t*	table)	/*!< in: quiesce this table */
{
	bool			exists = false;

	dict_mutex_enter_for_mysql();

	for (const dict_index_t* index = UT_LIST_GET_FIRST(table->indexes);
	     index != 0;
	     index = UT_LIST_GET_NEXT(indexes, index)) {

		if (index->type & DICT_FTS) {
			exists = true;
			break;
		}
	}

	dict_mutex_exit_for_mysql();

	return(exists);
}

/*********************************************************************//**
Quiesce the tablespace that the table resides in. */
UNIV_INTERN
void
row_quiesce_table_start(
/*====================*/
	dict_table_t*	table,		/*!< in: quiesce this table */
	trx_t*		trx)		/*!< in/out: transaction/session */
{
	ut_a(trx->mysql_thd != 0);
	ut_a(srv_n_purge_threads > 0);
	ut_ad(!srv_read_only_mode);

	char		table_name[MAX_FULL_NAME_LEN + 1];

	ut_a(trx->mysql_thd != 0);

	innobase_format_name(
		table_name, sizeof(table_name), table->name, FALSE);

	ib_logf(IB_LOG_LEVEL_INFO,
		"Sync to disk of '%s' started.", table_name);

	if (trx_purge_state() != PURGE_STATE_DISABLED) {
		trx_purge_stop();
	}

	for (ulint count = 0;
	     ibuf_merge_space(table->space) != 0
	     && !trx_is_interrupted(trx);
	     ++count) {
		if (!(count % 20)) {
			ib_logf(IB_LOG_LEVEL_INFO,
				"Merging change buffer entries for '%s'",
				table_name);
		}
	}

	if (!trx_is_interrupted(trx)) {
		buf_LRU_flush_or_remove_pages(
			table->space, BUF_REMOVE_FLUSH_WRITE, trx);

		if (trx_is_interrupted(trx)) {

			ib_logf(IB_LOG_LEVEL_WARN, "Quiesce aborted!");

		} else if (row_quiesce_write_cfg(table, trx->mysql_thd)
			   != DB_SUCCESS) {

			ib_logf(IB_LOG_LEVEL_WARN,
				"There was an error writing to the "
				"meta data file");
		} else {
			ib_logf(IB_LOG_LEVEL_INFO,
				"Table '%s' flushed to disk", table_name);
		}
	} else {
		ib_logf(IB_LOG_LEVEL_WARN, "Quiesce aborted!");
	}

	dberr_t	err = row_quiesce_set_state(table, QUIESCE_COMPLETE, trx);
	ut_a(err == DB_SUCCESS);
}

/*********************************************************************//**
Cleanup after table quiesce. */
UNIV_INTERN
void
row_quiesce_table_complete(
/*=======================*/
	dict_table_t*	table,		/*!< in: quiesce this table */
	trx_t*		trx)		/*!< in/out: transaction/session */
{
	ulint		count = 0;
	char		table_name[MAX_FULL_NAME_LEN + 1];

	ut_a(trx->mysql_thd != 0);

	innobase_format_name(
		table_name, sizeof(table_name), table->name, FALSE);

	/* We need to wait for the operation to complete if the
	transaction has been killed. */

	while (table->quiesce != QUIESCE_COMPLETE) {

		/* Print a warning after every minute. */
		if (!(count % 60)) {
			ib_logf(IB_LOG_LEVEL_WARN,
				"Waiting for quiesce of '%s' to complete",
				table_name);
		}

		/* Sleep for a second. */
		os_thread_sleep(1000000);

		++count;
	}

	/* Remove the .cfg file now that the user has resumed
	normal operations. Otherwise it will cause problems when
	the user tries to drop the database (remove directory). */
	char		cfg_name[OS_FILE_MAX_PATH];

	srv_get_meta_data_filename(table, cfg_name, sizeof(cfg_name));

	os_file_delete_if_exists(innodb_file_data_key, cfg_name);

	ib_logf(IB_LOG_LEVEL_INFO,
		"Deleting the meta-data file '%s'", cfg_name);

	if (trx_purge_state() != PURGE_STATE_DISABLED) {
		trx_purge_run();
	}

	dberr_t	err = row_quiesce_set_state(table, QUIESCE_NONE, trx);
	ut_a(err == DB_SUCCESS);
}

/*********************************************************************//**
Set a table's quiesce state.
@return DB_SUCCESS or error code. */
UNIV_INTERN
dberr_t
row_quiesce_set_state(
/*==================*/
	dict_table_t*	table,		/*!< in: quiesce this table */
	ib_quiesce_t	state,		/*!< in: quiesce state to set */
	trx_t*		trx)		/*!< in/out: transaction */
{
	ut_a(srv_n_purge_threads > 0);

	if (srv_read_only_mode) {

		ib_senderrf(trx->mysql_thd,
			    IB_LOG_LEVEL_WARN, ER_READ_ONLY_MODE);

		return(DB_UNSUPPORTED);

	} else if (table->space == TRX_SYS_SPACE) {

		char	table_name[MAX_FULL_NAME_LEN + 1];

		innobase_format_name(
			table_name, sizeof(table_name), table->name, FALSE);

		ib_senderrf(trx->mysql_thd, IB_LOG_LEVEL_WARN,
			    ER_TABLE_IN_SYSTEM_TABLESPACE, table_name);

		return(DB_UNSUPPORTED);
	} else if (row_quiesce_table_has_fts_index(table)) {

		ib_senderrf(trx->mysql_thd, IB_LOG_LEVEL_WARN,
			    ER_NOT_SUPPORTED_YET,
			    "FLUSH TABLES on tables that have an FTS index. "
			    "FTS auxiliary tables will not be flushed.");

	} else if (DICT_TF2_FLAG_IS_SET(table, DICT_TF2_FTS_HAS_DOC_ID)) {
		/* If this flag is set then the table may not have any active
		FTS indexes but it will still have the auxiliary tables. */

		ib_senderrf(trx->mysql_thd, IB_LOG_LEVEL_WARN,
			    ER_NOT_SUPPORTED_YET,
			    "FLUSH TABLES on a table that had an FTS index, "
			    "created on a hidden column, the "
			    "auxiliary tables haven't been dropped as yet. "
			    "FTS auxiliary tables will not be flushed.");
	}

	row_mysql_lock_data_dictionary(trx);

	dict_table_x_lock_indexes(table);

	switch (state) {
	case QUIESCE_START:
		break;

	case QUIESCE_COMPLETE:
		ut_a(table->quiesce == QUIESCE_START);
		break;

	case QUIESCE_NONE:
		ut_a(table->quiesce == QUIESCE_COMPLETE);
		break;
	}

	table->quiesce = state;

	dict_table_x_unlock_indexes(table);

	row_mysql_unlock_data_dictionary(trx);

	return(DB_SUCCESS);
}

