Fixes for wsrep provider options plugin

The plugin didn't work with options given on the command line or
config file.

Author: Daniele Sciascia

mysql-test/suite/wsrep/r/wsrep_provider_plugin_config.result

@@ -0,0 +1,24 @@
+SHOW VARIABLES LIKE 'wsrep_provider_pc_npvo';
+Variable_name	Value
+wsrep_provider_pc_npvo	ON
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'pc.npvo = [^;]+') AS provider_option;
+provider_option
+pc.npvo = true
+SHOW VARIABLES LIKE 'wsrep_provider_repl_max_ws_size';
+Variable_name	Value
+wsrep_provider_repl_max_ws_size	1024
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'repl.max_ws_size = [^;]+') AS provider_option;
+provider_option
+repl.max_ws_size = 1024
+SHOW VARIABLES LIKE 'wsrep_provider_evs_install_timeout';
+Variable_name	Value
+wsrep_provider_evs_install_timeout	8.100000
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'evs.install_timeout = [^;]+') AS provider_option;
+provider_option
+evs.install_timeout = PT8.1S
+SHOW VARIABLES LIKE 'wsrep_provider_gcache_size';
+Variable_name	Value
+wsrep_provider_gcache_size	10485760
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'gcache.size = [^;]+') AS provider_option;
+provider_option
+gcache.size = 10M

mysql-test/suite/wsrep/t/wsrep_provider_plugin_config.cnf

@@ -0,0 +1,26 @@
+!include include/default_my.cnf
+
+[mysqld.1]
+wsrep-on=ON
+wsrep-cluster-address=gcomm://
+wsrep-provider[email protected]_PROVIDER
+binlog-format=ROW
+plugin-wsrep-provider=ON
+wsrep-provider-base-port[email protected]
+
+# Test different type of options
+wsrep-provider-gcache-size=1024
+wsrep-provider-pc-npvo=ON
+wsrep-provider-evs-install-timeout=8.1
+
+# Repeat same variable again
+wsrep_provider_gcache_size=10M
+wsrep_provider_pc_npvo=OFF
+wsrep_provider_pc_npvo=ON
+
+# Option wsrep_provider_options can be used even if plugin-wsrep-provider
+# is enabled. However, settings in wsrep_provider_options have lower
+# precedence. For instance, the setting gcache.size below will
+# be ignored because it was already set through provider options
+# plugin above.
+wsrep_provider_options='gcache.size=20M;repl.max_ws_size=1024'

mysql-test/suite/wsrep/t/wsrep_provider_plugin_config.test

@@ -0,0 +1,14 @@
+--source include/have_wsrep.inc
+--source include/have_innodb.inc
+
+SHOW VARIABLES LIKE 'wsrep_provider_pc_npvo';
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'pc.npvo = [^;]+') AS provider_option;
+
+SHOW VARIABLES LIKE 'wsrep_provider_repl_max_ws_size';
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'repl.max_ws_size = [^;]+') AS provider_option;
+
+SHOW VARIABLES LIKE 'wsrep_provider_evs_install_timeout';
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'evs.install_timeout = [^;]+') AS provider_option;
+
+SHOW VARIABLES LIKE 'wsrep_provider_gcache_size';
+SELECT REGEXP_SUBSTR(@@wsrep_provider_options, 'gcache.size = [^;]+') AS provider_option;

sql/wsrep_mysqld.cc

@@ -45,6 +45,7 @@
 #include "wsrep_schema.h"
 #include "wsrep_xid.h"
 #include "wsrep_trans_observer.h"
+#include "wsrep_plugin.h" /* wsrep_load_provider_plugin_defaults() */
 #include "mysql/service_wsrep.h"
 #include <cstdio>
 #include <cstdlib>
@@ -897,9 +898,16 @@ int wsrep_init()
 
   Wsrep_server_state::init_provider_services();
   if (Wsrep_server_state::instance().load_provider(
-      wsrep_provider,
-      wsrep_provider_options,
-      Wsrep_server_state::instance().provider_services()))
+          wsrep_provider,
+          [&](wsrep::provider_options &opts) {
+            std::string defaults(wsrep_provider_options);
+            if (wsrep_load_provider_plugin_defaults(opts, defaults))
+            {
+              WSREP_ERROR("Failed to load provider plugin defaults");
+            }
+            return defaults;
+          },
+          Wsrep_server_state::instance().provider_services()))
   {
     WSREP_ERROR("Failed to load provider");
     Wsrep_server_state::deinit_provider_services();

sql/wsrep_plugin.cc

@@ -20,6 +20,7 @@
   in favor of single options which are initialized from provider.
 */
 
+#include "wsrep_plugin.h"
 #include "sql_plugin.h"
 #include "sql_priv.h"
 #include "sql_class.h"
@@ -131,7 +132,8 @@ static void wsrep_provider_sysvar_update(THD *thd,
   T new_value= *((T *) save);
 
   auto options= Wsrep_server_state::get_options();
-  if (options->set(opt->name(), make_option_value(new_value)))
+  if (options->set(Wsrep_server_state::get_provider(), opt->name(),
+                   make_option_value(new_value)))
   {
     my_error(ER_WRONG_VALUE_FOR_VAR, MYF(0), opt->name(),
              make_option_value(new_value)->as_string());
@@ -275,6 +277,107 @@ void wsrep_destroy_sysvar(struct st_mysql_sys_var *var)
   my_free(var);
 }
 
+struct st_mysql_sys_var
+{
+  MYSQL_PLUGIN_VAR_HEADER;
+};
+
+struct my_option_arg
+{
+  wsrep::provider_options::option *option;
+  struct st_mysql_sys_var *sysvar;
+  std::string *defaults;
+};
+
+static void my_option_init(struct my_option &my_opt,
+                           struct my_option_arg &my_arg)
+{
+  std::string option_name("wsrep-provider-");
+  option_name.append(my_arg.sysvar->name);
+  for (size_t i= 0; i < option_name.size(); ++i)
+    if (option_name[i] == '_')
+      option_name[i]= '-';
+  my_opt.name= my_strdup(PSI_INSTRUMENT_ME, option_name.c_str(), MYF(0));
+  my_opt.id= 0;
+  plugin_opt_set_limits(&my_opt, my_arg.sysvar);
+  my_opt.value= my_opt.u_max_value= *(uchar ***) (my_arg.sysvar + 1);
+  my_opt.block_size= 0;
+  my_opt.app_type= &my_arg;
+}
+
+static void my_option_deinit(struct my_option &my_opt)
+{
+  if (my_opt.name)
+    my_free((void*)my_opt.name);
+}
+
+static void make_my_options(std::vector<struct my_option_arg> &my_args,
+                            std::vector<struct my_option> &my_options)
+{
+  for (auto& arg : my_args)
+  {
+    struct my_option my_opt;
+    my_option_init(my_opt, arg);
+    my_options.push_back(my_opt);
+  }
+  struct my_option null_opt;
+  null_opt.name= NULL;
+  my_options.push_back(null_opt);
+}
+
+static void make_my_option_args(wsrep::provider_options &options,
+                                std::string &defaults,
+                                std::vector<struct my_option_arg> &my_args)
+{
+  options.for_each([&](wsrep::provider_options::option *opt) {
+    my_args.push_back({opt, wsrep_make_sysvar_for_option(opt), &defaults});
+  });
+}
+
+static my_bool option_changed(const struct my_option *opt, const char *value,
+                              const char *filename)
+{
+  my_option_arg *my_arg= (struct my_option_arg *) opt->app_type;
+  if (my_arg->defaults->size())
+    my_arg->defaults->append(";");
+  my_arg->defaults->append(my_arg->option->real_name());
+  my_arg->defaults->append("=");
+  my_arg->defaults->append(value);
+  return 0;
+}
+
+int wsrep_load_provider_plugin_defaults(wsrep::provider_options &options,
+                                        std::string &extra_options)
+{
+  int argc= orig_argc;
+  char **argv= orig_argv;
+
+  if (load_defaults(MYSQL_CONFIG_NAME, load_default_groups, &argc, &argv))
+  {
+    return 1;
+  }
+  char **defaults_argv= argv;
+
+  std::vector<struct my_option> my_options;
+  std::vector<struct my_option_arg> my_option_args;
+  make_my_option_args(options, extra_options, my_option_args);
+  make_my_options(my_option_args, my_options);
+
+  my_bool skip_unknown_orig= my_getopt_skip_unknown;
+  my_getopt_skip_unknown= TRUE;
+  int error= handle_options(&argc, &argv, &my_options[0], option_changed);
+  my_getopt_skip_unknown= skip_unknown_orig;
+
+  for (struct my_option &opt : my_options)
+    my_option_deinit(opt);
+  for (struct my_option_arg &arg : my_option_args)
+    wsrep_destroy_sysvar(arg.sysvar);
+  if (argv)
+    free_defaults(defaults_argv);
+
+  return error;
+}
+
 static int wsrep_provider_plugin_init(void *p)
 {
   WSREP_DEBUG("wsrep_provider_plugin_init()");

sql/wsrep_plugin.h

@@ -16,7 +16,8 @@
 #ifndef WSREP_PLUGIN_H
 #define WSREP_PLUGIN_H
 
-class option;
+#include "wsrep/provider_options.hpp"
+
 struct st_mysql_sys_var;
 
 /* Returns true if provider plugin was initialized and is active */
@@ -33,4 +34,9 @@ wsrep_make_sysvar_for_option(wsrep::provider_options::option *);
 /* Destroy a sysvar created by make_sysvar_for_option */
 void wsrep_destroy_sysvar(struct st_mysql_sys_var *);
 
+/* Parse defaults from config/command line, returns corresponding
+   provider options string */
+int wsrep_load_provider_plugin_defaults(wsrep::provider_options &,
+                                        std::string &);
+
 #endif /* WSREP_PLUGIN_H */

sql/wsrep_server_state.cc

@@ -99,9 +99,9 @@ int Wsrep_server_state::init_provider(const std::string& provider,
 int Wsrep_server_state::init_options()
 {
   if (!m_instance) return 1;
-  m_options= std::unique_ptr<wsrep::provider_options>(
-     new wsrep::provider_options(m_instance->provider()));
-  int ret= m_options->initial_options();
+  m_options=
+      std::unique_ptr<wsrep::provider_options>(new wsrep::provider_options());
+  int ret= m_options->initial_options(m_instance->provider());
   if (ret)
   {
     WSREP_ERROR("Failed to initialize provider options");