#At file:///home/sven/bzr/b41924-comments/5.1-rpl/ based on revid:zhenxing.he@stripped
2709 Sven Sandberg 2009-01-09
BUG#41924: high-level replication functions are not commented
Adding comments to some of the high-level functions in replication.
modified:
sql/log_event.h
sql/repl_failsafe.cc
sql/slave.cc
sql/sql_binlog.cc
sql/sql_lex.h
sql/sql_repl.cc
per-file messages:
sql/log_event.h
Fixed some mistakes in comments.
sql/repl_failsafe.cc
Added comment for show_slave_hosts()
sql/slave.cc
Added comment for show_master_info(), handle_slave_[sql|io](), and next_event()
sql/sql_binlog.cc
Added @param comment.
sql/sql_lex.h
Added comment for st_lex_master_info.
sql/sql_repl.cc
Added comments for functions executing a statement:
PURGE BINARY LOGS
START SLAVE
STOP SLAVE
RESET SLAVE
CHANGE MASTER
RESET MASTER
SHOW BINLOG EVENTS
SHOW MASTER STATUS
SHOW BINARY LOGS
=== modified file 'sql/log_event.h'
--- a/sql/log_event.h 2008-09-29 05:36:42 +0000
+++ b/sql/log_event.h 2009-01-09 10:33:53 +0000
@@ -319,18 +319,16 @@ struct sql_ex_info
#define Q_CHARSET_DATABASE_CODE 8
#define Q_TABLE_MAP_FOR_UPDATE_CODE 9
-/* Intvar event post-header */
+/* Intvar event data */
#define I_TYPE_OFFSET 0
#define I_VAL_OFFSET 1
-/* Rand event post-header */
-
+/* Rand event data */
#define RAND_SEED1_OFFSET 0
#define RAND_SEED2_OFFSET 8
-/* User_var event post-header */
-
+/* User_var event data */
#define UV_VAL_LEN_SIZE 4
#define UV_VAL_IS_NULL 1
#define UV_VAL_TYPE_SIZE 1
@@ -338,7 +336,6 @@ struct sql_ex_info
#define UV_CHARSET_NUMBER_SIZE 4
/* Load event post-header */
-
#define L_THREAD_ID_OFFSET 0
#define L_EXEC_TIME_OFFSET 4
#define L_SKIP_LINES_OFFSET 8
@@ -349,7 +346,6 @@ struct sql_ex_info
#define L_DATA_OFFSET LOAD_HEADER_LEN
/* Rotate event post-header */
-
#define R_POS_OFFSET 0
#define R_IDENT_OFFSET 8
@@ -2221,10 +2217,11 @@ protected:
@section Intvar_log_event_binary_format Binary Format
- The Post-Header has two components:
+ The Post-Header for this event type is empty. The Body has two
+ components:
<table>
- <caption>Post-Header for Intvar_log_event</caption>
+ <caption>Body for Intvar_log_event</caption>
<tr>
<th>Name</th>
@@ -2298,11 +2295,12 @@ private:
which are stored internally as two 64-bit numbers.
@section Rand_log_event_binary_format Binary Format
- This event type has no Post-Header. The Body of this event type has
- two components:
+
+ The Post-Header for this event type is empty. The Body has two
+ components:
<table>
- <caption>Post-Header for Intvar_log_event</caption>
+ <caption>Body for Rand_log_event</caption>
<tr>
<th>Name</th>
=== modified file 'sql/repl_failsafe.cc'
--- a/sql/repl_failsafe.cc 2008-03-20 11:22:02 +0000
+++ b/sql/repl_failsafe.cc 2009-01-09 10:33:53 +0000
@@ -644,6 +644,16 @@ err:
}
#endif
+
+/**
+ Execute a SHOW SLAVE HOSTS statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool show_slave_hosts(THD* thd)
{
List<Item> field_list;
=== modified file 'sql/slave.cc'
--- a/sql/slave.cc 2008-11-28 11:38:49 +0000
+++ b/sql/slave.cc 2009-01-09 10:33:53 +0000
@@ -1357,6 +1357,17 @@ int register_slave_on_master(MYSQL* mysq
}
+/**
+ Execute a SHOW SLAVE STATUS statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param mi Pointer to Master_info object for the IO thread.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool show_master_info(THD* thd, Master_info* mi)
{
// TODO: fix this for multi-master
@@ -2062,7 +2073,7 @@ int apply_event_and_update_pos(Log_event
fewer times, 0 is returned.
- init_master_info or init_relay_log_pos failed. (These are called
- if a failure occurs when applying the event.)</li>
+ if a failure occurs when applying the event.)
- An error occurred when updating the binlog position.
@@ -2307,8 +2318,14 @@ static int try_to_reconnect(THD *thd, MY
}
-/* Slave I/O Thread entry point */
+/**
+ Slave IO thread entry point.
+
+ @param arg Pointer to Master_info struct that holds information for
+ the IO thread.
+ @return Always 0.
+*/
pthread_handler_t handle_slave_io(void *arg)
{
THD *thd; // needs to be first for thread_stack
@@ -2616,8 +2633,14 @@ err:
}
-/* Slave SQL Thread entry point */
+/**
+ Slave SQL thread entry point.
+
+ @param arg Pointer to Relay_log_info object that holds information
+ for the SQL thread.
+ @return Always 0.
+*/
pthread_handler_t handle_slave_sql(void *arg)
{
THD *thd; /* needs to be first for thread_stack */
@@ -3710,6 +3733,16 @@ static IO_CACHE *reopen_relay_log(Relay_
}
+/**
+ Reads next event from the relay log. Should be called from the
+ slave IO thread.
+
+ @param rli Relay_log_info structure for the slave IO thread.
+
+ @return The event read, or NULL on error. If an error occurs, the
+ error is reported through the sql_print_information() or
+ sql_print_error() functions.
+*/
static Log_event* next_event(Relay_log_info* rli)
{
Log_event* ev;
=== modified file 'sql/sql_binlog.cc'
--- a/sql/sql_binlog.cc 2008-08-14 02:42:10 +0000
+++ b/sql/sql_binlog.cc 2009-01-09 10:33:53 +0000
@@ -18,7 +18,7 @@
#include "base64.h"
/**
- Execute a BINLOG statement
+ Execute a BINLOG statement.
To execute the BINLOG command properly the server needs to know
which format the BINLOG command's event is in. Therefore, the first
@@ -26,6 +26,9 @@
Format_description_log_event, as outputted by mysqlbinlog. This
Format_description_log_event is cached in
rli->description_event_for_exec.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
*/
void mysql_client_binlog_statement(THD* thd)
=== modified file 'sql/sql_lex.h'
--- a/sql/sql_lex.h 2008-11-04 07:55:43 +0000
+++ b/sql/sql_lex.h 2009-01-09 10:33:53 +0000
@@ -190,6 +190,15 @@ typedef struct st_lex_server_options
char *server_name, *host, *db, *username, *password, *scheme, *socket, *owner;
} LEX_SERVER_OPTIONS;
+
+/**
+ Structure to hold parameters for CHANGE MASTER or START/STOP SLAVE
+ or SHOW NEW MASTER.
+
+ Remark: this should not be confused with Master_info (and perhaps
+ would better be renamed to st_lex_replication_info). Some fields,
+ e.g., delay, are saved in Relay_log_info, not in Master_info.
+*/
typedef struct st_lex_master_info
{
char *host, *user, *password, *log_file_name;
=== modified file 'sql/sql_repl.cc'
--- a/sql/sql_repl.cc 2008-12-13 19:42:12 +0000
+++ b/sql/sql_repl.cc 2009-01-09 10:33:53 +0000
@@ -257,6 +257,17 @@ bool purge_error_message(THD* thd, int r
}
+/**
+ Execute a PURGE BINARY LOGS TO <log> command.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param to_log Name of the last log to purge.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool purge_master_logs(THD* thd, const char* to_log)
{
char search_file_name[FN_REFLEN];
@@ -273,6 +284,17 @@ bool purge_master_logs(THD* thd, const c
}
+/**
+ Execute a PURGE BINARY LOGS BEFORE <date> command.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param purge_time Date before which logs should be purged.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool purge_master_logs_before_date(THD* thd, time_t purge_time)
{
if (!mysql_bin_log.is_open())
@@ -765,6 +787,20 @@ err:
DBUG_VOID_RETURN;
}
+
+/**
+ Execute a START SLAVE statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param mi Pointer to Master_info object for the slave's IO thread.
+
+ @param net_report If true, saves the exit status into thd->main_da.
+
+ @retval 0 success
+ @retval 1 error
+*/
int start_slave(THD* thd , Master_info* mi, bool net_report)
{
int slave_errno= 0;
@@ -890,6 +926,19 @@ int start_slave(THD* thd , Master_info*
}
+/**
+ Execute a STOP SLAVE statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param mi Pointer to Master_info object for the slave's IO thread.
+
+ @param net_report If true, saves the exit status into thd->main_da.
+
+ @retval 0 success
+ @retval 1 error
+*/
int stop_slave(THD* thd, Master_info* mi, bool net_report )
{
DBUG_ENTER("stop_slave");
@@ -942,20 +991,17 @@ int stop_slave(THD* thd, Master_info* mi
}
-/*
- Remove all relay logs and start replication from the start
+/**
+ Execute a RESET SLAVE statement.
- SYNOPSIS
- reset_slave()
- thd Thread handler
- mi Master info for the slave
-
- RETURN
- 0 ok
- 1 error
-*/
+ @param thd Pointer to THD object of the client thread executing the
+ statement.
+ @param mi Pointer to Master_info object for the slave.
+ @retval 0 success
+ @retval 1 error
+*/
int reset_slave(THD *thd, Master_info* mi)
{
MY_STAT stat_area;
@@ -1070,6 +1116,18 @@ void kill_zombie_dump_threads(uint32 sla
}
+/**
+ Execute a CHANGE MASTER statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @param mi Pointer to Master_info object belonging to the slave's IO
+ thread.
+
+ @retval FALSE success
+ @retval TRUE error
+*/
bool change_master(THD* thd, Master_info* mi)
{
int thread_mask;
@@ -1283,6 +1341,16 @@ bool change_master(THD* thd, Master_info
DBUG_RETURN(FALSE);
}
+
+/**
+ Execute a RESET MASTER statement.
+
+ @param thd Pointer to THD object of the client thread executing the
+ statement.
+
+ @retval 0 success
+ @retval 1 error
+*/
int reset_master(THD* thd)
{
if (!mysql_bin_log.is_open())
@@ -1312,6 +1380,15 @@ int cmp_master_pos(const char* log_file_
}
+/**
+ Execute a SHOW BINLOG EVENTS statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool mysql_show_binlog_events(THD* thd)
{
Protocol *protocol= thd->protocol;
@@ -1462,6 +1539,15 @@ err:
}
+/**
+ Execute a SHOW MASTER STATUS statement.
+
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
+
+ @retval FALSE success
+ @retval TRUE failure
+*/
bool show_binlog_info(THD* thd)
{
Protocol *protocol= thd->protocol;
@@ -1495,18 +1581,15 @@ bool show_binlog_info(THD* thd)
}
-/*
- Send a list of all binary logs to client
+/**
+ Execute a SHOW BINARY LOGS statement.
- SYNOPSIS
- show_binlogs()
- thd Thread specific variable
+ @param thd Pointer to THD object for the client thread executing the
+ statement.
- RETURN VALUES
- FALSE OK
- TRUE error
+ @retval FALSE success
+ @retval TRUE failure
*/
-
bool show_binlogs(THD* thd)
{
IO_CACHE *index_file;
| Thread |
|---|
| • bzr commit into mysql-5.1 branch (sven:2709) Bug#41924 | Sven Sandberg | 9 Jan |
