MDEV-33187: Make mariadb-hotcopy compatible with DBI:MariaDB

scripts/mysqlhotcopy.sh

@@ -189,21 +189,38 @@ $opt{quiet} = 0 if $opt{debug};
 $opt{allowold} = 1 if $opt{keepold};
 
 # --- connect to the database ---
+## Socket takes precedence.
 my $dsn;
-$dsn  = ";host=" . (defined($opt{host}) ? $opt{host} : "localhost");
-$dsn .= ";port=$opt{port}" if $opt{port};
-$dsn .= ";mariadb_socket=$opt{socket}" if $opt{socket};
+my $prefix= 'mysql';
 
-# use mariadb_read_default_group=mysqlhotcopy so that [client] and
-# [mysqlhotcopy] groups will be read from standard options files.
+if (eval {DBI->install_driver("MariaDB")}) {
+  $dsn ="DBI:MariaDB:;";
+  $prefix= 'mariadb';
+}
+else {
+  $dsn = "DBI:mysql:;";
+}
 
-my $dbh = DBI->connect("DBI:MariaDB:$dsn;mariadb_read_default_group=mysqlhotcopy",
-                        $opt{user}, $opt{password},
+if ($opt{socket} and -S $opt{socket})
+{
+  $dsn .= "${prefix}_socket=$opt{socket}";
+}
+else
 {
-    RaiseError => 1,
-    PrintError => 0,
-    AutoCommit => 1,
-});
+  $dsn .= "host=" . $opt{host};
+  if ($opt{host} ne "localhost")
+  {
+    $dsn .= ";port=". $opt{port};
+  }
+}
+
+$dsn .= ";mariadb_read_default_group=mysqlhotcopy";
+
+# use mariadb_read_default_group=mysqlhotcopy so that [client] and
+# [mysqlhotcopy] groups will be read from standard options files.
+# make the connection to MariaDB
+my $dbh= DBI->connect($dsn, $opt{user}, $opt{password}, { RaiseError => 1, PrintError => 0}) ||
+                      die("Can't make a connection to the MariaDB server.\n The error: $DBI::errstr");
 
 # --- check that checkpoint table exists if specified ---
 if ( $opt{checkpoint} ) {