it only worked if mroonga plugin wasn't installed before (normal case),
but then it didn't need to delete anything.

if, by some glitch, mroonga was already installed, it would delete
mroonga from mysql.plugin, but INSTALL would fail (as mroonga was running),
and the script aborted, leaving mroonga not in mysql.plugin at all.

Solution for Debian/Ubuntu: install a trigger to restart mysqld
automatically whenever a package changes something in /etc/mysql
or in /etc/systemd/system/mariadb.service.d

remove manual libcurl3 dependency.
it'll be automatically added (libcurl3 or libcurl4, whatever was
actually used)

to avoid "using unique option prefix 'backup' is error-prone", there is
already --backup option there.

There is a tiny chance for race condition during MDL acquisition.

If table is renamed just prior to
SELECT 1 FROM <table_name> LIMIT 0

then this query would  fail, yet mariabackup --backup does not handle
it as fatal error and continues, only to fail later during file copy.

The fix is to die on error, of MDL lock query fails.

make it not to fail when `show engine innodb status` output
contains a double quote

don't tell users to set the root password if they're using unix_socket

there's an assert that catches it

Don't let SET PASSWORD to set the password, if auth_string is set.

Now SET PASSWORD always sets the plugin/auth_string fields and clears
the password field (on pre-plugin mysql.user table it works as before).

MDEV-14578: mysql_install_db install unix_socket plugin when --auth-root-authentication-method=socket

post-merge fixes

MDEV-14578: mysql_install_db install unix_socket plugin when --auth-root-authentication-method=socket

$ cmake -DPLUGIN_AUTH_SOCKET=STATIC ../mariadb-server-10.2/

$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-static --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-static' ...
OK

$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

$ cmake -DPLUGIN_AUTH_SOCKET=NO ../mariadb-server-10.2/
$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-none --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-none' ...
ERROR: 1126  Can't open shared library '.../plugin/auth_socket/auth_socket.so' (errno: 2, cannot open shared object file: No such file or directory)
2018-05-01 11:38:56 0 [ERROR] Aborting

$ cmake -DPLUGIN_AUTH_SOCKET=DYNAMIC ../mariadb-server-10.2/
$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-dyn --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-dyn' ...
OK
$ ./sql/mysqld  --datadir=/tmp/mysqldatadir-auth-dyn  --lc-messages-dir=${PWD}/sql/share --plugin-dir=./plugin/auth_socket/
$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

$ sudo make install
$ sudo chmod a+rwx /usr/local/mysql/data
$ cd /usr/local/mysql/
$ scripts/mysql_install_db  --auth-root-socket-user=dan --auth-root-authentication-method=socket
Installing MariaDB/MySQL system tables in './data' ...
OK
..
$ bin/mysqld_safe
$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

Merges #767

In RPM/DEB packages - always ld-preload jemalloc, instead
of linking ha_tokudb.so with it.

Keep linking in bintars, because they don't install cnf files
in the correct locations.

This reverts commit d39629f0.

Because running mtr for many hours with no output whatsoever
is not really what we should do.

And in 5.5 `make test` just works anyway, nothing to fix here.

my_option strucures for command-line variables should be set properly.

settings.

MDEV-16534 PPC64: Unexpected error with a negative value into auto-increment columns in HEAP, MyISAM, ARIA

Revert 7bbe324f
Fix the bug differently (in log_event.cc)
Fix the test case to actually fail without the bug fix

RocksDB will only build with libzstd support if libzstd version is
>=1.1.13. Unfortunately CMake's FindPackage claims it found version
1.1.13 when we have 1.1.12-1 installed, so a workaround with
CheckFunctionExists is used to properly check for correct libzstd
support.