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-rw-r--r--libmariadb/plugins/connection/CMakeLists.txt6
-rw-r--r--libmariadb/plugins/connection/replication.c357
2 files changed, 363 insertions, 0 deletions
diff --git a/libmariadb/plugins/connection/CMakeLists.txt b/libmariadb/plugins/connection/CMakeLists.txt
new file mode 100644
index 00000000..743cf2b0
--- /dev/null
+++ b/libmariadb/plugins/connection/CMakeLists.txt
@@ -0,0 +1,6 @@
+# Replication
+REGISTER_PLUGIN(TARGET replication
+ TYPE MARIADB_CLIENT_PLUGIN_CONNECTION
+ CONFIGURATIONS STATIC DYNAMIC OFF
+ DEFAULT OFF
+ SOURCES ${CC_SOURCE_DIR}/plugins/connection/replication.c)
diff --git a/libmariadb/plugins/connection/replication.c b/libmariadb/plugins/connection/replication.c
new file mode 100644
index 00000000..0e7a18b7
--- /dev/null
+++ b/libmariadb/plugins/connection/replication.c
@@ -0,0 +1,357 @@
+/************************************************************************************
+ Copyright (C) 2015-2018 MariaDB Corporation AB
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this library; if not see <http://www.gnu.org/licenses>
+ or write to the Free Software Foundation, Inc.,
+ 51 Franklin St., Fifth Floor, Boston, MA 02110, USA
+
+ Part of this code includes code from the PHP project which
+ is freely available from http://www.php.net
+*************************************************************************************/
+
+/* MariaDB Connection plugin for load balancing */
+
+#include <ma_global.h>
+#include <ma_sys.h>
+#include <errmsg.h>
+#include <mysql.h>
+#include <mysql/client_plugin.h>
+#include <string.h>
+#include <ma_string.h>
+#include <ma_common.h>
+
+#ifndef WIN32
+#include <sys/time.h>
+#endif
+
+/* function prototypes */
+MYSQL *repl_connect(MYSQL *mysql, const char *host, const char *user, const char *passwd,
+ const char *db, unsigned int port, const char *unix_socket, unsigned long clientflag);
+void repl_close(MYSQL *mysql);
+int repl_command(MYSQL *mysql,enum enum_server_command command, const char *arg,
+ size_t length, my_bool skipp_check, void *opt_arg);
+int repl_set_optionsv(MYSQL *mysql, unsigned int option, ...);
+
+#define MARIADB_MASTER 0
+#define MARIADB_SLAVE 1
+
+static struct st_mariadb_api *libmariadb_api= NULL;
+
+#ifndef PLUGIN_DYNAMIC
+MARIADB_CONNECTION_PLUGIN replication_client_plugin =
+#else
+MARIADB_CONNECTION_PLUGIN _mysql_client_plugin_declaration_ =
+#endif
+{
+ MARIADB_CLIENT_CONNECTION_PLUGIN,
+ MARIADB_CLIENT_CONNECTION_PLUGIN_INTERFACE_VERSION,
+ "replication",
+ "Georg Richter",
+ "MariaDB connection plugin for load balancing",
+ {1, 0, 0},
+ "LGPL",
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ repl_connect,
+ repl_close,
+ repl_set_optionsv,
+ repl_command,
+ NULL,
+ NULL
+};
+
+typedef struct st_conn_repl {
+ MARIADB_PVIO *pvio[2];
+ MYSQL *slave_mysql;
+ my_bool read_only;
+ my_bool round_robin;
+ char *url;
+ char *host[2];
+ unsigned int port[2];
+ unsigned int current_type;
+} REPL_DATA;
+
+#define SET_SLAVE(mysql, data)\
+do {\
+ mysql->net.pvio= data->pvio[MARIADB_SLAVE]; \
+ data->current_type= MARIADB_SLAVE;\
+} while(0)
+
+#define SET_MASTER(mysql, data)\
+do {\
+ mysql->net.pvio= data->pvio[MARIADB_MASTER];\
+ data->current_type= MARIADB_MASTER;\
+} while(0)
+
+
+/* parse url
+ * Url has the following format:
+ * master[:port],slave1[:port],slave2[:port],..,slaven[:port]
+ *
+ */
+
+my_bool repl_parse_url(const char *url, REPL_DATA *data)
+{
+ char *p;
+ char *slaves[64];
+ int port[64], i,num_slaves= 0;
+
+ if (!url || url[0] == 0)
+ return 1;
+
+ memset(slaves, 0, 64 * sizeof(char *));
+ memset(&port, 0, 64 * sizeof(int));
+
+ memset(data->host, 0, 2 * sizeof(char *));
+ memset(data->port, 0, 2 * sizeof(int));
+
+ if (!data->url)
+ data->url= strdup(url);
+ data->host[MARIADB_MASTER]= p= data->url;
+
+ /* get slaves */
+ while((p && (p= strchr(p, ','))))
+ {
+ *p= '\0';
+ p++;
+ if (*p)
+ {
+ slaves[num_slaves]= p;
+ num_slaves++;
+ }
+ }
+
+ if (!num_slaves)
+ return 0;
+ if (num_slaves == 1)
+ data->host[MARIADB_SLAVE]= slaves[0];
+ else
+ {
+ int random_nr;
+#ifndef WIN32
+ struct timeval tp;
+ gettimeofday(&tp,NULL);
+ srand(tp.tv_usec / 1000 + tp.tv_sec * 1000);
+#else
+ srand(GetTickCount());
+#endif
+
+ random_nr= rand() % num_slaves;
+ data->host[MARIADB_SLAVE]= slaves[random_nr];
+ }
+
+ /* check ports */
+ for (i=0; i < 2 && data->host[i]; i++)
+ {
+ /* We need to be aware of IPv6 addresses: According to RFC3986 sect. 3.2.2
+ hostnames have to be enclosed in square brackets if a port is given */
+ if (data->host[i][0]== '[' && strchr(data->host[i], ':') && (p= strchr(data->host[i],']')))
+ {
+ /* ignore first square bracket */
+ memmove(data->host[i], data->host[i]+1, strlen(data->host[i]) - 1);
+ p= strchr(data->host[i],']');
+ *p= 0;
+ p++;
+ }
+ else
+ p= data->host[i];
+ if (p && (p= strchr(p, ':')))
+ {
+ *p= '\0';
+ p++;
+ data->port[i]= atoi(p);
+ }
+ }
+
+ return 0;
+}
+
+MYSQL *repl_connect(MYSQL *mysql, const char *host, const char *user, const char *passwd,
+ const char *db, unsigned int port, const char *unix_socket, unsigned long clientflag)
+{
+ REPL_DATA *data= NULL;
+ MA_CONNECTION_HANDLER *hdlr= mysql->extension->conn_hdlr;
+
+ if (!libmariadb_api)
+ libmariadb_api= mysql->methods->api;
+
+ if ((data= (REPL_DATA *)hdlr->data))
+ {
+ data->pvio[MARIADB_MASTER]->methods->close(data->pvio[MARIADB_MASTER]);
+ data->pvio[MARIADB_MASTER]= 0;
+ repl_close(mysql);
+ }
+
+ if (!(data= calloc(1, sizeof(REPL_DATA))))
+ {
+ mysql->methods->set_error(mysql, CR_OUT_OF_MEMORY, "HY000", 0);
+ return NULL;
+ }
+ memset(data->pvio, 0, 2 * sizeof(MARIADB_PVIO *));
+
+ if (repl_parse_url(host, data))
+ goto error;
+
+ /* try to connect to master */
+ if (!(libmariadb_api->mysql_real_connect(mysql, data->host[MARIADB_MASTER], user, passwd, db,
+ data->port[MARIADB_MASTER] ? data->port[MARIADB_MASTER] : port, unix_socket, clientflag)))
+ goto error;
+
+ data->pvio[MARIADB_MASTER]= mysql->net.pvio;
+ hdlr->data= data;
+ SET_MASTER(mysql, data);
+
+ /* to allow immediate access without connection delay, we will start
+ * connecting to slave(s) in background */
+
+ /* if slave connection will fail, we will not return error but use master instead */
+ if (!(data->slave_mysql= libmariadb_api->mysql_init(NULL)) ||
+ !(mysql->methods->db_connect(data->slave_mysql, data->host[MARIADB_SLAVE], user, passwd, db,
+ data->port[MARIADB_SLAVE] ? data->port[MARIADB_SLAVE] : port, unix_socket, clientflag)))
+ {
+ if (data->slave_mysql)
+ libmariadb_api->mysql_close(data->slave_mysql);
+ data->pvio[MARIADB_SLAVE]= NULL;
+ }
+ else
+ {
+ data->pvio[MARIADB_SLAVE]= data->slave_mysql->net.pvio;
+ data->slave_mysql->net.pvio->mysql= mysql;
+ }
+ return mysql;
+error:
+ if (data)
+ {
+ if (data->url)
+ free(data->url);
+ free(data);
+ }
+ return NULL;
+}
+
+void repl_close(MYSQL *mysql)
+{
+ MA_CONNECTION_HANDLER *hdlr= mysql->extension->conn_hdlr;
+ REPL_DATA *data= (REPL_DATA *)hdlr->data;
+
+ /* restore master */
+ SET_MASTER(mysql, data);
+
+ /* free slave information and close connection */
+ if (data->pvio[MARIADB_SLAVE])
+ {
+ /* restore mysql */
+ data->pvio[MARIADB_SLAVE]->mysql= data->slave_mysql;
+ libmariadb_api->mysql_close(data->slave_mysql);
+ data->pvio[MARIADB_SLAVE]= NULL;
+ data->slave_mysql= NULL;
+ }
+
+ /* free masrwe information and close connection */
+ free(data->url);
+ free(data);
+ mysql->extension->conn_hdlr->data= NULL;
+}
+
+static my_bool is_slave_command(const char *buffer, size_t buffer_len)
+{
+ const char *buffer_end= buffer + buffer_len;
+
+ for (; buffer < buffer_end; ++buffer)
+ {
+ char c;
+ if (isalpha(c=*buffer))
+ {
+ if (tolower(c) == 's')
+ return 1;
+ return 0;
+ }
+ }
+ return 0;
+}
+
+static my_bool is_slave_stmt(MYSQL *mysql, const char *buffer)
+{
+ unsigned long stmt_id= uint4korr(buffer);
+ LIST *stmt_list= mysql->stmts;
+
+ for (; stmt_list; stmt_list= stmt_list->next)
+ {
+ MYSQL_STMT *stmt= (MYSQL_STMT *)stmt_list->data;
+ if (stmt->stmt_id == stmt_id)
+ return 1;
+ }
+ return 0;
+}
+
+
+int repl_command(MYSQL *mysql,enum enum_server_command command, const char *arg,
+ size_t length,
+ my_bool skipp_check __attribute__((unused)),
+ void *opt_arg __attribute__((unused)))
+{
+ REPL_DATA *data= (REPL_DATA *)mysql->extension->conn_hdlr->data;
+
+ /* if we don't have slave or slave became unavailable root traffic to master */
+ if (!data->pvio[MARIADB_SLAVE] || !data->read_only)
+ {
+ SET_MASTER(mysql, data);
+ return 0;
+ }
+ switch(command) {
+ case COM_QUERY:
+ case COM_STMT_PREPARE:
+ if (is_slave_command(arg, length))
+ SET_SLAVE(mysql, data)
+ else
+ SET_MASTER(mysql,data)
+ break;
+ case COM_STMT_EXECUTE:
+ case COM_STMT_FETCH:
+ if (data->pvio[MARIADB_SLAVE]->mysql->stmts && is_slave_stmt(data->pvio[MARIADB_SLAVE]->mysql, arg))
+ SET_SLAVE(mysql, data)
+ else
+ SET_MASTER(mysql,data)
+ break;
+
+ default:
+ SET_MASTER(mysql,data)
+ break;
+ }
+ return 0;
+}
+
+int repl_set_optionsv(MYSQL *mysql, unsigned int option, ...)
+{
+ REPL_DATA *data= (REPL_DATA *)mysql->extension->conn_hdlr->data;
+ va_list ap;
+ void *arg1;
+ int rc= 0;
+
+ va_start(ap, option);
+ arg1= va_arg(ap, void *);
+
+ switch(option) {
+ case MARIADB_OPT_CONNECTION_READ_ONLY:
+ data->read_only= *(my_bool *)arg1;
+ break;
+ default:
+ rc= -1;
+ break;
+ }
+ va_end(ap);
+ return(rc);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 20:43:39 +0000