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Binlogserver sends GTID_LIST Fake Event when a MariaDB 10 slave connects with GTID

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Now sending GTID_LIST Fake Event when a MariaDB10 Slave connects with
GTID
This commit is contained in:
MassimilianoPinto
2017-04-05 15:22:01 +02:00
parent ce6b52ab39
commit e0a12820b6
3 changed files with 204 additions and 2 deletions
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192
server/modules/routing/binlogrouter/blr_slave.c
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@ -270,6 +270,11 @@ static bool blr_slave_gtid_request(ROUTER_INSTANCE *router,
bool req_file,
unsigned long req_pos);
static int blr_send_fake_gtid_list(ROUTER_SLAVE *slave,
const char *gtid,
uint32_t serverid);
static bool blr_parse_gtid(const char *gtid, MARIADB_GTID_ELEMS *info);
void poll_fake_write_event(DCB *dcb);
/**
@ -2416,6 +2421,23 @@ blr_slave_binlog_dump(ROUTER_INSTANCE *router, ROUTER_SLAVE *slave, GWBUF *queue
blr_slave_read_ste(router, slave, fde_end_pos);
}
/* Add GTID_LIST Fake Event before sending any new event */
if (slave->mariadb10_compat &&
slave->mariadb_gtid)
{
if (!blr_send_fake_gtid_list(slave,
slave->mariadb_gtid,
router->masterid))
{
// ERROR
slave->state = BLRS_ERRORED;
dcb_close(slave->dcb);
return 1;
}
slave->lastEventReceived = MARIADB10_GTID_GTID_LIST_EVENT;
}
/* Set dcb_callback for the events reading routine */
dcb_add_callback(slave->dcb, DCB_REASON_DRAINED, blr_slave_callback, slave);
slave->state = BLRS_DUMPING;
@ -6935,3 +6957,173 @@ static bool blr_slave_gtid_request(ROUTER_INSTANCE *router,
return true;
}
/**
* Create a Fake GTID_LIST event
*
* The routine creates a Fake GTID_LIST event
*
* @param slave The connected client
* @param gtid The requested GTID from client
* @param serverid The router server_id to add
* in the replication event header
* @return Fake GTID_LIST event on success or NULL
*
*/
static GWBUF *blr_build_fake_gtid_list_event(ROUTER_SLAVE *slave,
const char *gtid,
uint32_t serverid)
{
int len;
GWBUF *gl_event;
uint8_t *ptr;
REP_HEADER hdr;
uint32_t chksum;
MARIADB_GTID_ELEMS req_gtid = {};
if (!blr_parse_gtid(gtid, &req_gtid))
{
return NULL;
}
/**
* We only support one GTID in the GTID_LIST event
*
* Paylod is:
* BINLOG_EVENT_HDR_LEN + 4 bytes GTID count + 1 GTID
*/
len = BINLOG_EVENT_HDR_LEN + 4 + 1 * (4 + 4 + 8);
/* Add CRC32 bytes if needed */
len += slave->nocrc ? 0 : BINLOG_EVENT_CRC_SIZE;
/* Allocate space for packet header, status and data */
if ((gl_event = gwbuf_alloc(MYSQL_HEADER_LEN + 1 + len)) == NULL)
{
return NULL;
}
/* Add 1 byte to paylod for status indicator */
hdr.payload_len = len + 1;
/* Add sequence and increment it */
hdr.seqno = slave->seqno++;
/* Set status indicator byte to OK */
hdr.ok = 0;
/* No timestamp is required */
hdr.timestamp = 0L;
/* GTID Event Type */
hdr.event_type = MARIADB10_GTID_GTID_LIST_EVENT;
hdr.serverid = serverid;
hdr.event_size = len;
/* Next pos is set */
hdr.next_pos = slave->binlog_pos;
/* Artificial Event Flag */
hdr.flags = 0x20;
/* Add replication hdr to resp */
ptr = blr_build_header(gl_event, &hdr);
/* Add 4 bytes count */
/* Note: We set only 1 GTID in GTID_LIST Event */
encode_value(ptr, 1, 32);
ptr += 4;
/* Add 4 bytes domain id */
encode_value(ptr, req_gtid.domain_id, 32);
ptr += 4;
/* Add 4 bytes server id*/
encode_value(ptr, req_gtid.server_id, 32);
ptr += 4;
/* Add 8 bytes sequence */
encode_value(ptr, req_gtid.seq_no, 64);
ptr += 8;
/* Now add the CRC to the fake binlog rotate event */
if (!slave->nocrc)
{
/*
* First checksum of an empty buffer
* then the checksum of the event portion of the message:
* we do not include the len, seq number and ok byte that are part of
* first 5 bytes of the message.
* We also do not include the 4 byte checksum itself.
*/
chksum = crc32(0L, NULL, 0);
chksum = crc32(chksum,
GWBUF_DATA(gl_event) + MYSQL_HEADER_LEN + 1,
hdr.event_size - BINLOG_EVENT_CRC_SIZE);
encode_value(ptr, chksum, 32);
}
return gl_event;
}
/**
* Create and send a Fake GTID_LIST event
*
* @param slave Current slave server
* @param gtid The requested GTID from client
* @oaram serverid The server_id to use in replication header
* @return Non-zero if data has been sent
*/
static int blr_send_fake_gtid_list(ROUTER_SLAVE *slave,
const char *gtid,
uint32_t serverid)
{
/* Build Fake GTID_LIST Event */
GWBUF *gl_event = blr_build_fake_gtid_list_event(slave,
gtid,
serverid);
/* Send Fake GTID_LIST Event or return 0*/
return gl_event ? slave->dcb->func.write(slave->dcb, gl_event) : 0;
}
/**
* Extract the GTID the client requested
*
* @param gtid Then input GTID
* @param info The GTID structure to fil
* @return True for a parsed GTID string or false
*/
static bool blr_parse_gtid(const char *gtid, MARIADB_GTID_ELEMS *info)
{
const char *ptr = gtid;
int read = 0;
int len = strlen(gtid);
while (ptr < gtid + len)
{
if (!isdigit(*ptr))
{
ptr++;
}
else
{
char *end;
switch (read)
{
case 0:
info->domain_id = strtoul(ptr, &end, 10);
break;
case 1:
info->server_id = strtoul(ptr, &end, 10);
break;
case 2:
info->seq_no = strtoul(ptr, &end, 10);
break;
}
read++;
ptr = end;
}
}
return (info->server_id && info->seq_no) ? true : false;
}