博客遷移至:
從事DBA工作多年
MYSQL源碼也是頭一次接觸
嘗試記錄下自己看MYSQL5.7源碼的歷程
申明:個人Python編程很溜，但是C++還停在白痴水平，源碼理解方面有點弱，如發現有錯誤的地方，輕噴
目錄：
51ak帶你看MYSQL5.7源碼1：main入口函數 （2018-03-21)
51ak帶你看MYSQL5.7源碼2：編譯現有的代碼 （2018-03-22)
51ak帶你看MYSQL5.7源碼3：修改代碼實現你的第一個Mysql版本 （2018-03-23)
51ak帶你看MYSQL5.7源碼4：實現SQL黑名單功能（2018-04-11)
去MYSQL官網下源碼：https://dev.mysql.com/downloads/mysql/
選 SOURCE CODE
下載解壓。選VS code來查看，
用VS打開發現這些目錄 ，根據了解到的目錄結構說明，我們關注標紅的兩個目錄，SQL是MYSQL的核心代碼 ，STORGE里是各個存儲引擎的代碼
打開sql/main.cc 發現只有一個函數，引用了同級目錄下的mysqld_main(int argc, char **argv);
F12跟過去，到了msyqld.cc下的這個過程 ，這里就是整個SERVER進程 的入口
接下來就一個巨大的代碼段，來啟動MYSQLD進程
我按個人的理解加了注釋如下：
#ifdef _WIN32
int win_main(int argc, char **argv)
#else
int mysqld_main(int argc, char **argv)
#endif
{
/*
Perform basic thread library and malloc initialization,
to be able to read defaults files and parse options.
*/
my_progname= argv[0]; /*注: 記下mysql進程名*/
#ifndef _WIN32
#ifdef WITH_PERFSCHEMA_STORAGE_ENGINE
pre_initialize_performance_schema();
#endif /*WITH_PERFSCHEMA_STORAGE_ENGINE */
// For windows, my_init() is called from the win specific mysqld_main
if (my_init()) // init my_sys library & pthreads
{
sql_print_error("my_init() failed.");
flush_error_log_messages();
return 1;
}
#endif /* _WIN32 */
orig_argc= argc;
orig_argv= argv;
my_getopt_use_args_separator= TRUE;
my_defaults_read_login_file= FALSE;
/*注: 這里是去讀配置文件里的啟動項,讀的時候還帶入了argv ，應該是argv優行，*/
if (load_defaults(MYSQL_CONFIG_NAME, load_default_groups, &argc, &argv))
{
flush_error_log_messages();
return 1;
}
my_getopt_use_args_separator= FALSE;
defaults_argc= argc;
defaults_argv= argv;
remaining_argc= argc;
remaining_argv= argv;
/* Must be initialized early for comparison of options name */
system_charset_info= &my_charset_utf8_general_ci;
/* Write mysys error messages to the error log. */
local_message_hook= error_log_print;
int ho_error;
#ifdef WITH_PERFSCHEMA_STORAGE_ENGINE
/*
Initialize the array of performance schema instrument configurations.
*/
init_pfs_instrument_array();
#endif /* WITH_PERFSCHEMA_STORAGE_ENGINE */
/*注: 這里跟過去發現還是在處理啟動變量*/
ho_error= handle_early_options();
#if !defined(_WIN32) && !defined(EMBEDDED_LIBRARY)
if (opt_bootstrap && opt_daemonize)
{
fprintf(stderr, "Bootstrap and daemon options are incompatible.\n");
exit(MYSQLD_ABORT_EXIT);
}
if (opt_daemonize && log_error_dest == disabled_my_option &&
(isatty(STDOUT_FILENO) || isatty(STDERR_FILENO)))
{
fprintf(stderr, "Please enable --log-error option or set appropriate "
"redirections for standard output and/or standard error "
"in daemon mode.\n");
exit(MYSQLD_ABORT_EXIT);
}
if (opt_daemonize)
{
if (chdir("/") < 0)
{
fprintf(stderr, "Cannot change to root director: %s\n",
strerror(errno));
exit(MYSQLD_ABORT_EXIT);
}
if ((pipe_write_fd= mysqld::runtime::mysqld_daemonize()) < 0)
{
fprintf(stderr, "mysqld_daemonize failed \n");
exit(MYSQLD_ABORT_EXIT);
}
}
#endif
/*注: 還是在處理啟動變量。。。*/
init_sql_statement_names();
sys_var_init();
ulong requested_open_files;
adjust_related_options(&requested_open_files);
#ifdef WITH_PERFSCHEMA_STORAGE_ENGINE
if (ho_error == 0)
{
if (!opt_help && !opt_bootstrap)
{
/* Add sizing hints from the server sizing parameters. */
pfs_param.m_hints.m_table_definition_cache= table_def_size;
pfs_param.m_hints.m_table_open_cache= table_cache_size;
pfs_param.m_hints.m_max_connections= max_connections;
pfs_param.m_hints.m_open_files_limit= requested_open_files;
pfs_param.m_hints.m_max_prepared_stmt_count= max_prepared_stmt_count;
PSI_hook= initialize_performance_schema(&pfs_param);
if (PSI_hook == NULL && pfs_param.m_enabled)
{
pfs_param.m_enabled= false;
sql_print_warning("Performance schema disabled (reason: init failed).");
}
}
}
#else
/*
Other provider of the instrumentation interface should
initialize PSI_hook here:
- HAVE_PSI_INTERFACE is for the instrumentation interface
- WITH_PERFSCHEMA_STORAGE_ENGINE is for one implementation
of the interface,
but there could be alternate implementations, which is why
these two defines are kept separate.
*/
#endif /* WITH_PERFSCHEMA_STORAGE_ENGINE */
#ifdef HAVE_PSI_INTERFACE
/*
Obtain the current performance schema instrumentation interface,
if available.
*/
if (PSI_hook)
{
PSI *psi_server= (PSI*) PSI_hook->get_interface(PSI_CURRENT_VERSION);
if (likely(psi_server != NULL))
{
set_psi_server(psi_server);
/*
Now that we have parsed the command line arguments, and have initialized
the performance schema itself, the next step is to register all the
server instruments.
*/
init_server_psi_keys();
/* Instrument the main thread */
PSI_thread *psi= PSI_THREAD_CALL(new_thread)(key_thread_main, NULL, 0);
PSI_THREAD_CALL(set_thread_os_id)(psi);
PSI_THREAD_CALL(set_thread)(psi);
/*
Now that some instrumentation is in place,
recreate objects which were initialised early,
so that they are instrumented as well.
*/
my_thread_global_reinit();
}
}
#endif /* HAVE_PSI_INTERFACE */
/*注: ERRLOG初始化*/
init_error_log();
/* Initialize audit interface globals. Audit plugins are inited later. */
mysql_audit_initialize();
#ifndef EMBEDDED_LIBRARY
Srv_session::module_init();
#endif
/*
Perform basic query log initialization. Should be called after
MY_INIT, as it initializes mutexes.
*/
/*注: QUERYLOG初始化*/
query_logger.init();
if (ho_error)
{
/*
Parsing command line option failed,
Since we don't have a workable remaining_argc/remaining_argv
to continue the server initialization, this is as far as this
code can go.
This is the best effort to log meaningful messages:
- messages will be printed to stderr, which is not redirected yet,
- messages will be printed in the NT event log, for windows.
*/
flush_error_log_messages();
/*
Not enough initializations for unireg_abort()
Using exit() for windows.
*/
exit (MYSQLD_ABORT_EXIT);
}
if (init_common_variables())
unireg_abort(MYSQLD_ABORT_EXIT); // Will do exit
/*注: 系統信號初始化*/
my_init_signals();
size_t guardize= 0;
#ifndef _WIN32
int retval= pthread_attr_getguardsize(&connection_attrib, &guardize);
DBUG_ASSERT(retval == 0);
if (retval != 0)
guardize= my_thread_stack_size;
#endif
#if defined(__ia64__) || defined(__ia64)
/*
Peculiar things with ia64 platforms - it seems we only have half the
stack size in reality, so we have to double it here
*/
guardize= my_thread_stack_size;
#endif
my_thread_attr_setstacksize(&connection_attrib,
my_thread_stack_size + guardize);
{
/* Retrieve used stack size; Needed for checking stack overflows */
size_t stack_size= 0;
my_thread_attr_getstacksize(&connection_attrib, &stack_size);
/* We must check if stack_size = 0 as Solaris 2.9 can return 0 here */
if (stack_size && stack_size < (my_thread_stack_size + guardize))
{
sql_print_warning("Asked for %lu thread stack, but got %ld",
my_thread_stack_size + guardize, (long) stack_size);
#if defined(__ia64__) || defined(__ia64)
my_thread_stack_size= stack_size / 2;
#else
my_thread_stack_size= static_cast<ulong>(stack_size - guardize);
#endif
}
}
#ifndef DBUG_OFF
test_lc_time_sz();
srand(static_cast<uint>(time(NULL)));
#endif
#ifndef _WIN32
if ((user_info= check_user(mysqld_user)))
{
#if HAVE_CHOWN
if (unlikely(opt_initialize))
{
/* need to change the owner of the freshly created data directory */
MY_STAT stat;
char errbuf[MYSYS_STRERROR_SIZE];
bool must_chown= true;
/* fetch the directory's owner */
if (!my_stat(mysql_real_data_home, &stat, MYF(0)))
{
sql_print_information("Can't read data directory's stats (%d): %s."
"Assuming that it's not owned by the same user/group",
my_errno(),
my_strerror(errbuf, sizeof(errbuf), my_errno()));
}
/* Don't change it if it's already the same as SElinux stops this */
else if(stat.st_uid == user_info->pw_uid &&
stat.st_gid == user_info->pw_gid)
must_chown= false;
if (must_chown &&
chown(mysql_real_data_home, user_info->pw_uid, user_info->pw_gid)
)
{
sql_print_error("Can't change data directory owner to %s", mysqld_user);
unireg_abort(1);
}
}
#endif
#if defined(HAVE_MLOCKALL) && defined(MCL_CURRENT)
if (locked_in_memory) // getuid() == 0 here
set_effective_user(user_info);
else
#endif
set_user(mysqld_user, user_info);
}
#endif // !_WIN32
/*
initiate key migration if any one of the migration specific
options are provided.
*/
/*注: 這一段應該是跟遷移有關的，不是很懂*/
if (opt_keyring_migration_source ||
opt_keyring_migration_destination ||
migrate_connect_options)
{
Migrate_keyring mk;
if (mk.init(remaining_argc, remaining_argv,
opt_keyring_migration_source,
opt_keyring_migration_destination,
opt_keyring_migration_user,
opt_keyring_migration_host,
opt_keyring_migration_password,
opt_keyring_migration_socket,
opt_keyring_migration_port))
{
sql_print_error(ER_DEFAULT(ER_KEYRING_MIGRATION_STATUS),
"failed");
log_error_dest= "stderr";
flush_error_log_messages();
unireg_abort(MYSQLD_ABORT_EXIT);
}
if (mk.execute())
{
sql_print_error(ER_DEFAULT(ER_KEYRING_MIGRATION_STATUS),
"failed");
log_error_dest= "stderr";
flush_error_log_messages();
unireg_abort(MYSQLD_ABORT_EXIT);
}
sql_print_information(ER_DEFAULT(ER_KEYRING_MIGRATION_STATUS),
"successfull");
log_error_dest= "stderr";
flush_error_log_messages();
unireg_abort(MYSQLD_SUCCESS_EXIT);
}
/*
We have enough space for fiddling with the argv, continue
*/
/*注：設置DATA變量*/
if (my_setwd(mysql_real_data_home,MYF(MY_WME)) && !opt_help)
{
sql_print_error("failed to set datadir to %s", mysql_real_data_home);
unireg_abort(MYSQLD_ABORT_EXIT); /* purecov: inspected */
}
/*注：設置BINLOG*/
//If the binlog is enabled, one needs to provide a server-id
if (opt_bin_log && !(server_id_supplied) )
{
sql_print_error("You have enabled the binary log, but you haven't provided "
"the mandatory server-id. Please refer to the proper "
"server start-up parameters documentation");
unireg_abort(MYSQLD_ABORT_EXIT);
}
/*
The subsequent calls may take a long time : e.g. innodb log read.
Thus set the long running service control manager timeout
*/
#if defined(_WIN32)
Service.SetSlowStarting(slow_start_timeout);
#endif
/*注：這個很重要。核心模塊在這里啟動了*/
if (init_server_components())
unireg_abort(MYSQLD_ABORT_EXIT);
/*
Each server should have one UUID. We will create it automatically, if it
does not exist.
*/
if (init_server_auto_options())
{
sql_print_error("Initialization of the server's UUID failed because it could"
" not be read from the auto.cnf file. If this is a new"
" server, the initialization failed because it was not"
" possible to generate a new UUID.");
unireg_abort(MYSQLD_ABORT_EXIT);
}
/*注：下面這段跟SID有關*/
/*
Add server_uuid to the sid_map. This must be done after
server_uuid has been initialized in init_server_auto_options and
after the binary log (and sid_map file) has been initialized in
init_server_components().
No error message is needed: init_sid_map() prints a message.
Strictly speaking, this is not currently needed when
opt_bin_log==0, since the variables that gtid_state->init
initializes are not currently used in that case. But we call it
regardless to avoid possible future bugs if gtid_state ever
needs to do anything else.
*/
global_sid_lock->wrlock();
int gtid_ret= gtid_state->init();
global_sid_lock->unlock();
if (gtid_ret)
unireg_abort(MYSQLD_ABORT_EXIT);
// Initialize executed_gtids from mysql.gtid_executed table.
if (gtid_state->read_gtid_executed_from_table() == -1)
unireg_abort(1);
if (opt_bin_log)
{
/*
Initialize GLOBAL.GTID_EXECUTED and GLOBAL.GTID_PURGED from
gtid_executed table and binlog files during server startup.
*/
Gtid_set *executed_gtids=
const_cast<Gtid_set *>(gtid_state->get_executed_gtids());
Gtid_set *lost_gtids=
const_cast<Gtid_set *>(gtid_state->get_lost_gtids());
Gtid_set *gtids_only_in_table=
const_cast<Gtid_set *>(gtid_state->get_gtids_only_in_table());
Gtid_set *previous_gtids_logged=
const_cast<Gtid_set *>(gtid_state->get_previous_gtids_logged());
Gtid_set purged_gtids_from_binlog(global_sid_map, global_sid_lock);
Gtid_set gtids_in_binlog(global_sid_map, global_sid_lock);
Gtid_set gtids_in_binlog_not_in_table(global_sid_map, global_sid_lock);
if (mysql_bin_log.init_gtid_sets(>ids_in_binlog,
&purged_gtids_from_binlog,
opt_master_verify_checksum,
true/*true=need lock*/,
NULL/*trx_parser*/,
NULL/*gtid_partial_trx*/,
true/*is_server_starting*/))
unireg_abort(MYSQLD_ABORT_EXIT);
global_sid_lock->wrlock();
purged_gtids_from_binlog.dbug_print("purged_gtids_from_binlog");
gtids_in_binlog.dbug_print("gtids_in_binlog");
if (!gtids_in_binlog.is_empty() &&
!gtids_in_binlog.is_subset(executed_gtids))
{
gtids_in_binlog_not_in_table.add_gtid_set(>ids_in_binlog);
if (!executed_gtids->is_empty())
gtids_in_binlog_not_in_table.remove_gtid_set(executed_gtids);
/*
Save unsaved GTIDs into gtid_executed table, in the following
four cases:
1. the upgrade case.
2. the case that a slave is provisioned from a backup of
the master and the slave is cleaned by RESET MASTER
and RESET SLAVE before this.
3. the case that no binlog rotation happened from the
last RESET MASTER on the server before it crashes.
4. The set of GTIDs of the last binlog is not saved into the
gtid_executed table if server crashes, so we save it into
gtid_executed table and executed_gtids during recovery
from the crash.
*/
if (gtid_state->save(>ids_in_binlog_not_in_table) == -1)
{
global_sid_lock->unlock();
unireg_abort(MYSQLD_ABORT_EXIT);
}
executed_gtids->add_gtid_set(>ids_in_binlog_not_in_table);
}
/* gtids_only_in_table= executed_gtids - gtids_in_binlog */
if (gtids_only_in_table->add_gtid_set(executed_gtids) !=
RETURN_STATUS_OK)
{
global_sid_lock->unlock();
unireg_abort(MYSQLD_ABORT_EXIT);
}
gtids_only_in_table->remove_gtid_set(>ids_in_binlog);
/*
lost_gtids = executed_gtids -
(gtids_in_binlog - purged_gtids_from_binlog)
= gtids_only_in_table + purged_gtids_from_binlog;
*/
DBUG_ASSERT(lost_gtids->is_empty());
if (lost_gtids->add_gtid_set(gtids_only_in_table) != RETURN_STATUS_OK ||
lost_gtids->add_gtid_set(&purged_gtids_from_binlog) !=
RETURN_STATUS_OK)
{
global_sid_lock->unlock();
unireg_abort(MYSQLD_ABORT_EXIT);
}
/* Prepare previous_gtids_logged for next binlog */
if (previous_gtids_logged->add_gtid_set(>ids_in_binlog) !=
RETURN_STATUS_OK)
{
global_sid_lock->unlock();
unireg_abort(MYSQLD_ABORT_EXIT);
}
/*
Write the previous set of gtids at this point because during
the creation of the binary log this is not done as we cannot
move the init_gtid_sets() to a place before openning the binary
log. This requires some investigation.
/Alfranio
*/
Previous_gtids_log_event prev_gtids_ev(>ids_in_binlog);
global_sid_lock->unlock();
(prev_gtids_ev.common_footer)->checksum_alg=
static_cast<enum_binlog_checksum_alg>(binlog_checksum_options);
if (prev_gtids_ev.write(mysql_bin_log.get_log_file()))
unireg_abort(MYSQLD_ABORT_EXIT);
mysql_bin_log.add_bytes_written(
prev_gtids_ev.common_header->data_written);
if (flush_io_cache(mysql_bin_log.get_log_file()) ||
mysql_file_sync(mysql_bin_log.get_log_file()->file, MYF(MY_WME)))
unireg_abort(MYSQLD_ABORT_EXIT);
mysql_bin_log.update_binlog_end_pos();
(void) RUN_HOOK(server_state, after_engine_recovery, (NULL));
}
/*注： 網絡相關的初始化*/
if (init_ssl())
unireg_abort(MYSQLD_ABORT_EXIT);
if (network_init())
unireg_abort(MYSQLD_ABORT_EXIT);
#ifdef _WIN32
#ifndef EMBEDDED_LIBRARY
if (opt_require_secure_transport &&
!opt_enable_shared_memory && !opt_use_ssl &&
!opt_initialize && !opt_bootstrap)
{
sql_print_error("Server is started with --require-secure-transport=ON "
"but no secure transports (SSL or Shared Memory) are "
"configured.");
unireg_abort(MYSQLD_ABORT_EXIT);
}
#endif
#endif
/*
Initialize my_str_malloc(), my_str_realloc() and my_str_free()
*/
my_str_malloc= &my_str_malloc_mysqld;
my_str_free= &my_str_free_mysqld;
my_str_realloc= &my_str_realloc_mysqld;
error_handler_hook= my_message_sql;
/* Save pid of this process in a file */
if (!opt_bootstrap)
create_pid_file();
/* Read the optimizer cost model configuration tables */
if (!opt_bootstrap)
reload_optimizer_cost_constants();
if (mysql_rm_tmp_tables() || acl_init(opt_noacl) ||
my_tz_init((THD *)0, default_tz_name, opt_bootstrap) ||
grant_init(opt_noacl))
{
abort_loop= true;
delete_pid_file(MYF(MY_WME));
unireg_abort(MYSQLD_ABORT_EXIT);
}
if (!opt_bootstrap)
servers_init(0);
if (!opt_noacl)
{
#ifdef HAVE_DLOPEN
udf_init();
#endif
}
/*注：設置SHOW STATUS時的變量*/
init_status_vars();
/* If running with bootstrap, do not start replication. */
if (opt_bootstrap)
opt_skip_slave_start= 1;
/*注：初始化BINLOG的值了*/
check_binlog_cache_size(NULL);
check_binlog_stmt_cache_size(NULL);
binlog_unsafe_map_init();
/* If running with bootstrap, do not start replication. */
if (!opt_bootstrap)
{
// Make @@slave_skip_errors show the nice human-readable value.
set_slave_skip_errors(&opt_slave_skip_errors);
/*
init_slave() must be called after the thread keys are created.
*/
if (server_id != 0)
init_slave(); /* Ignoring errors while configuring replication. */
}
#ifdef WITH_PERFSCHEMA_STORAGE_ENGINE
initialize_performance_schema_acl(opt_bootstrap);
/*
Do not check the structure of the performance schema tables
during bootstrap:
- the tables are not supposed to exist yet, bootstrap will create them
- a check would print spurious error messages
*/
if (! opt_bootstrap)
check_performance_schema();
#endif
initialize_information_schema_acl();
execute_ddl_log_recovery();
(void) RUN_HOOK(server_state, after_recovery, (NULL));
if (Events::init(opt_noacl || opt_bootstrap))
unireg_abort(MYSQLD_ABORT_EXIT);
#ifndef _WIN32
// Start signal handler thread.
start_signal_handler();
#endif
/*注：啟動了*/
if (opt_bootstrap)
{
start_processing_signals();
int error= bootstrap(mysql_stdin);
unireg_abort(error ? MYSQLD_ABORT_EXIT : MYSQLD_SUCCESS_EXIT);
}
if (opt_init_file && *opt_init_file)
{
if (read_init_file(opt_init_file))
unireg_abort(MYSQLD_ABORT_EXIT);
}
/*
Event must be invoked after error_handler_hook is assigned to
my_message_sql, otherwise my_message will not cause the event to abort.
*/
if (mysql_audit_notify(AUDIT_EVENT(MYSQL_AUDIT_SERVER_STARTUP_STARTUP),
(const char **) argv, argc))
unireg_abort(MYSQLD_ABORT_EXIT);
#ifdef _WIN32
create_shutdown_thread();
#endif
start_handle_manager();
create_compress_gtid_table_thread();
sql_print_information(ER_DEFAULT(ER_STARTUP),
my_progname,
server_version,
#ifdef HAVE_SYS_UN_H
(opt_bootstrap ? (char*) "" : mysqld_unix_port),
#else
(char*) "",
#endif
mysqld_port,
MYSQL_COMPILATION_COMMENT);
#if defined(_WIN32)
Service.SetRunning();
#endif
start_processing_signals();
#ifdef WITH_NDBCLUSTER_STORAGE_ENGINE
/* engine specific hook, to be made generic */
if (ndb_wait_setup_func && ndb_wait_setup_func(opt_ndb_wait_setup))
{
sql_print_warning("NDB : Tables not available after %lu seconds."
" Consider increasing --ndb-wait-setup value",
opt_ndb_wait_setup);
}
#endif
if (!opt_bootstrap)
{
/*
Execute an I_S query to implicitly check for tables using the deprecated
partition engine. No need to do this during bootstrap. We ignore the
return value from the query execution. Note that this must be done after
NDB is initialized to avoid polluting the server with invalid table shares.
*/
if (!opt_disable_partition_check)
{
sql_print_information(
"Executing 'SELECT * FROM INFORMATION_SCHEMA.TABLES;' "
"to get a list of tables using the deprecated partition "
"engine.");
sql_print_information("Beginning of list of non-natively partitioned tables");
(void) bootstrap_single_query(
"SELECT TABLE_SCHEMA, TABLE_NAME FROM INFORMATION_SCHEMA.TABLES "
"WHERE CREATE_OPTIONS LIKE '%partitioned%';");
sql_print_information("End of list of non-natively partitioned tables");
}
}
/*
Set opt_super_readonly here because if opt_super_readonly is set
in get_option, it will create problem while setting up event scheduler.
*/
set_super_read_only_post_init();
DBUG_PRINT("info", ("Block, listening for incoming connections"));
(void)MYSQL_SET_STAGE(0 ,__FILE__, __LINE__);
server_operational_state= SERVER_OPERATING;
(void) RUN_HOOK(server_state, before_handle_connection, (NULL));
/*注：設置連接池*/
#if defined(_WIN32)
setup_conn_event_handler_threads();
#else
mysql_mutex_lock(&LOCK_socket_listener_active);
// Make it possible for the signal handler to kill the listener.
socket_listener_active= true;
mysql_mutex_unlock(&LOCK_socket_listener_active);
if (opt_daemonize)
mysqld::runtime::signal_parent(pipe_write_fd,1);
mysqld_socket_acceptor->connection_event_loop();
#endif /* _WIN32 */
server_operational_state= SERVER_SHUTTING_DOWN;
DBUG_PRINT("info", ("No longer listening for incoming connections"));
mysql_audit_notify(MYSQL_AUDIT_SERVER_SHUTDOWN_SHUTDOWN,
MYSQL_AUDIT_SERVER_SHUTDOWN_REASON_SHUTDOWN,
MYSQLD_SUCCESS_EXIT);
terminate_compress_gtid_table_thread();
/*
Save set of GTIDs of the last binlog into gtid_executed table
on server shutdown.
*/
if (opt_bin_log)
if (gtid_state->save_gtids_of_last_binlog_into_table(false))
sql_print_warning("Failed to save the set of Global Transaction "
"Identifiers of the last binary log into the "
"mysql.gtid_executed table while the server was "
"shutting down. The next server restart will make "
"another attempt to save Global Transaction "
"Identifiers into the table.");
#ifndef _WIN32
mysql_mutex_lock(&LOCK_socket_listener_active);
// Notify the signal handler that we have stopped listening for connections.
socket_listener_active= false;
mysql_cond_broadcast(&COND_socket_listener_active);
mysql_mutex_unlock(&LOCK_socket_listener_active);
#endif // !_WIN32
#ifdef HAVE_PSI_THREAD_INTERFACE
/*
Disable the main thread instrumentation,
to avoid recording events during the shutdown.
*/
PSI_THREAD_CALL(delete_current_thread)();
#endif
DBUG_PRINT("info", ("Waiting for shutdown proceed"));
int ret= 0;
#ifdef _WIN32
if (shutdown_thr_handle.handle)
ret= my_thread_join(&shutdown_thr_handle, NULL);
shutdown_thr_handle.handle= NULL;
if (0 != ret)
sql_print_warning("Could not join shutdown thread. error:%d", ret);
#else
if (signal_thread_id.thread != 0)
ret= my_thread_join(&signal_thread_id, NULL);
signal_thread_id.thread= 0;
if (0 != ret)
sql_print_warning("Could not join signal_thread. error:%d", ret);
#endif
/*注：請理退出*/
clean_up(1);
mysqld_exit(MYSQLD_SUCCESS_EXIT);
}
好了，第一天，只看這一節代碼就夠了