Functional index extractor code used to raise an invalid
error message when the user-defined extractor function
returns a scalar instead of a table.

Closes #4553

Wrap throwing lua_newthread in luaT_newthread using luaT_cpcall
to process arising error properly.

Closes #4556

End recovery (which means building secondary indexes) just after
last known log file was read. This allows fast switch to hot standby
instance without any delay for secondary index to be built.
Due to engine_end_recovery carryover, xdir_collect_inprogress,
previously being called from it, is now moved to garbage collector.

Closes #4135

expmask indicated necessity to recompile statement after parameter was
bound: it might turn out that parameter can affect query plan. However,
part of this mechanism has been removed long ago as a SQLite's legacy.
In its current state expmask is likely to be useless and assertions
involving it are obviously unsuitable. This patch completely removes
expmask and related routines.

Closes #4566

Console client's eval() method in case of an error at
reading from a socket was trying to return a variable
declared in a different view scope. Instead, the
error should be raised to drop the connection.

Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

When we handle unix console connection we should setup
eos if only we meet "\set output" command in a stream.
For example there could be "\set language" which should
not affect eos settings.

Closes #4568

Reported-by: Alexander Turenko <alexander.turenko@tarantool.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

This will allow us to reuse this map in other routines
and same time optimize memory allocation a bit.

Part-of #4568

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

All user-defined functions feature type of returned value (if it
is not specified during function creation, it is assumed to be
ANY), but currently it is ignored. This patch introduces check
which verifies that returned value is of specified in function's
definition type. There's no attempt at implicit conversion to
specified (target) type - returned value must be literally of
the specified type.

Closes #4387

Start using comprehensive serializer luaL_tofield() to prepare
LUA arguments for UDFs. This allows to support cdata types
returned from Lua function.

Needed for #4387

@TarantoolBot document
Title: UDF returning nil or box.NULL in SQL

Values nil and box.NULL returned by UDF in SQL
both transformed to SQL NULL and are equal.

Example:
tarantool> box.execute("SELECT LUA('return box.NULL') is NULL
                               and LUA('return nil') is NULL")
---
- metadata:
  - name: LUA('return box.NULL') is NULL and LUA('return nil') is NULL
    type: boolean
  rows:
  - [true]
...

This patch introduces handling the situation when UDF returns
too many values. Previously Tarantool used to silently use
the first value returned. Now an error is raised.

Moreover a test coverage is improved also for the situation when
no value is returned.

Needed for #4387

Rows_per_wal option was deprecated because it can be covered by
wal_max_size. In order not to complicate WAL code with that
option's support this commit drops it completely.

In some tests the option was used to create several small xlog
files. Now the same is done via wal_max_size. Where it was
needed, number of rows per wal is estimated as wal_max_size / 50.
Because struct xrow_header size ~= 50 not counting paddings and
body.

Note, file box/configuration.result was deleted here, because it
is a stray result file, and it contained the rows_per_wal option
mentioning. Its test was dropped much earlier in
fdc3d1dd.

Closes #3762

In patch c6bea65f I
added a bug - replication/misc leaves a bad value in
box.cfg.replication. Before that patch the test was
resetting this to empty replication. In my patch I
forgot about that, and left there the value

    {box.cfg.listen, "12345"}

This patch cleans it up.

Follow up #3760

This patch changes OP_Function parameters convention: now a
function's name is passed instead of pointer to the function
object. This allows to normally handle the situation, when UDF
has been deleted to the moment of the VDBE code execution.
In particular case this may happen with CK constraints that
refers to a deleted persistent function.

Closes #4176

Closes #4244

@TarantoolBot document
Title: an ability to disable CK constraints

Now it is possible to disable and enable ck constraints.
All ck constraints are enabled by default when Tarantool is
configured. Ck constraints checks are not performed during
standard recovery, but performed during force_recovery -
all conflicting tuples are skipped in case of ck_constraint
conflict.

To change CK constraint "is_enabled" state, call
-- in LUA
ck_obj:enable(new_state in {true, false})
-- in SQL
ALTER TABLE {TABLE_NAME} {EN, DIS}ABLE CHECK CONSTRAINT {CK_NAME};

Example:
box.space.T6.ck_constraint.ck_unnamed_T6_1:enable(false)
box.space.T6.ck_constraint.ck_unnamed_T6_1
- space_id: 512
  is_enabled: false
  name: ck_unnamed_T6_1
  expr: a < 10
box.space.T6:insert({11})
-- passed
box.execute("ALTER TABLE t6 ENABLE CHECK CONSTRAINT \"ck_unnamed_T6_1\"")
box.space.T6:insert({12})
- error: 'Check constraint failed ''ck_unnamed_T6_1'': a < 10'

Now it is possible to disable and enable ck constraints in LUA.
This option is persistent. All ck constraints are constructed
in enabled state when Tarantool is configured. This ability
may be usefulwhen processed data is verified and constraints
validation is not required. For instance, during casual recovery
process there's no need to provide any checks since data is
assumed to be consistent.

Persisting is_enabled flag is an important feature.
If the option is not stored the following scenario is
possible:
- the option is turned off
- data is changed so that a constraint is violated
- the system is restarted while the option state is lost
- there is no way (even in theory) to discover it and find that
  data is incorrect.

Part of #4244

test_run:wait_upstream() and test_run:wait_downstream() now wait until
an upstream / a downstream appears. This prevents an attempt to index a
nil value when one of those functions are called before a record about a
peer appears in box.info.replication. It was observed on
replication/show_error_on_disconnect test after commit
c6bea65f ('replication: recfg with 0
quorum returns immediately').

Fixes #4563.

The trigger pointer in the sql_trigger structure is a dead code
now, so it could be deleted.

Needed for #4343

Prior to this patch, the auto-increment feature could only be set
in an INTEGER field of PRIMARY KEY if the PRIMARY KEY consisted of
a single field. It was not possible to use this feature if the
PRIMARY KEY consisted of more than one field. This patch defines
two ways to set AUTOINCREMENT for any INTEGER or UNSIGNED field of
PRIMARY KEY.

Closes #4217

@TarantoolBot document
Title: The auto-increment feature for multipart PK
The auto-increment feature can be set to any INTEGER or UNSIGNED
field of PRIMARY KEY using one of two ways:
1) AUTOINCREMENT in column definition:
CREATE TABLE t (i INT, a INT AUTOINCREMENT, PRIMARY KEY (i, a));
CREATE TABLE t (i INT AUTOINCREMENT, a INT, PRIMARY KEY (i, a));
2) AUTOINCREMENT in PRIMARY KEY definition:
CREATE TABLE t (i INT, a INT, PRIMARY KEY (i, a AUTOINCREMENT));
CREATE TABLE t (i INT, a INT, PRIMARY KEY (i AUTOINCREMENT, a));

Replication quorum 0 not only affects orphan status, but also,
according to documentation, makes box.cfg() return immediately
regardless of whether connections to upstreams are established.

It was not so before the patch. What is worse, even with non 0
quorum the instance was blocked on reconfiguration for connect
timeout seconds, if at least one node is not connected.

Now quorum is respected on reconfiguration. On a bootstrap it is
still impossible to return earlier than
replication_connect_timeout, because nodes need to choose some
cluster settings. Too early start would make it impossible -
cluster's participants will just start and choose different
cluster UUIDs.

Closes #3760

A successfully fetched remote instance ballot isn't updated during
bootstrap procedure. This leads to a case when different instances
choose different masters as their bootstrap leaders.

Imagine such a situation.
You start instance A without replication set up. Instance A successfully
bootstraps.
You also have instances B and C both with replication set up to {A, B,
C} and replication_connect_quorum set to 3
You first start instance B. It doesn't proceed to choosing a leader
until one of the events happens: either the replication_connect_timeout
runs out, or instance C is up and starts listening on its port.
B has established connection to A and fetched its ballot, with some
vclock, say, {1: 1}.
B retries connection to C every replication_timeout seconds.
Then you start instance C. Instance C succeeds in connecting to A and B
right away and bootstraps from instance A. Instance A registers C in its
_cluster table. This registration is replicated to instance C.
Meanwhile, instance C is trying to sync with quorum instances (which is
3), and stays in orphan mode.
Now replication_timeout on instance B finally runs out. It retries a
previously unsuccessful connection to C and succeeds. C sends its ballot
to B with vclock = {1: 2, 2:0} (in our example), since it has already
incremented it after _cluster registration.
B sees that C has a greater vclock than A, and chooses to bootstrap from
C instead of A. C is orphan and rejects B's attempt to join. B dies.

To fix such ungentlemanlike behaviour of C, we should at least include
loading status in ballot and prefer fully bootstrapped instances to the
ones still syncing with other replicas.
We also need to use a separate flag instead of ballot's already existent
is_ro, since we still want to prefer loading instances over the ones
explicitly configured to be read-only.

Closes #4527

During rework of the console lua mode series
the declaration of variable has been lost and
this cause test case for remote unix console
connection to fail.

Fixes issue from c358398c

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

To be consistent in naming scheme, for example
we already have parse_operators.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

The other modules would be able to find out which eos marker
is currently active. For example when reading replies from
remote server via text based console protocol.

@TarantoolBot document
Title: > require('console').eos()

Returns a string with currently active end of string marker.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

If we change output mode on remote machine via
text-based session

 node a (server)
 ------
 require('console').listen('unix/:/tmp/X.sock')
 ...

 node b (client)
 ------
 require('console').connect('unix/:/tmp/X.sock')
 connected to unix/:/tmp/X.sock
 ...
 unix/:/tmp/X.sock> \set output lua

the client get stuck forever, it is because the text
wire protocol waits for yaml eos terminator which of
course never hit the peer, because lua mode uses own
one.

Thus to fix this problem we have to preprocess the text
we're passing to the server, just like we do in local
console. So we reuse command parsing code and remember
current output terminator in text_connection_mt instance.

Another problem is that named default output mode. There
could be a mixed environment where server operates in
default lua mode but client connects with yaml mode. To
break a tie we yield "\set output" command with current
output mode when establishing a connection. Since the
output format is per-session bound this doesn't affect
any other connections on a server.

Part-of #3834

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

We will need to parse and verify "\set" commands
in remote console text-wire protocol thus to not
duplicate the code lets factor helper out for
reuse sake.

Part-of #3834

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

This will help us to distinguish end of string/stream
in text protocols (such as remote console connection).

Note that we start printing ";" terminator for every
lua output. Actually current yaml output does the
same but inside console.c module.

And since lua output is yet a new feature in stabilization
phase we're safe to make such changes without breaking api.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

This allows lua to not create them every call since
they are constant speeding up processing a bit.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

Sole symbols (such as box.NULL) are not processed
by serpent "custom" symbols feature, since they
are not in table.

Thus we should process them separately. Without it
we have

 > require('console').set_default_output("lua,block")
 > ;
 > box.NULL
 > "cdata<void %*>: NULL";

instead of

 > box.NULL
 > box.NULL;

as it should be.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

fiber_stack_destroy() doesn't depend on cord() helper but
rather accepts slab cache pointer in arguments, lets
make the same in fiber_stack_create() helper, otherwise
it looks quite imbalanced.

Signed-off-by: Kirill Yukhin <kyukhin@tarantool.org>

The mprotect() syscall may fail due to heavy memory
pressure (say there is no enough resources to split
VMAs and etc).

In this case we must not proceed without guard page
but refuse to create a new fiber.

Closes #4541

Signed-off-by: Kirill Yukhin <kyukhin@tarantool.org>

This will allow us to call it from inside fiber_stack_create
as we need to clean up resources on error.

Part-of #4541

Signed-off-by: Kirill Yukhin <kyukhin@tarantool.org>

Count lines in the json parsing structure. It is needed to print
the number of line and column where a mistake was made.

Closes #3316

(cherry picked from commit 9f9bd3eb2d064129ff6b1a764140ebef242d7ff7)

Code to run main script (passed via command line args, or
interactive console) has a footer where it notifies systemd,
logs a happened error, and panics.

Before the patch that code was unreachable in case of any
exception in a main script, because panic happened earlier. Now a
happened exception is correctly carried to the footer with proper
error processing.

A first and obvious solution was replace all panics with diag_set
and use fiber_join on the script runner fiber. But appeared, that
the fiber running a main script can't be joined. This is because
normally it exits via os.exit() which never returns and therefore
its caller never dies = can't be joined.

The patch solves this problem by passing main fiber diag to the
script runner by pointer, eliminating fiber_join necessity.

Closes #4382

xlog/panic_on_broken_lsn includes waiting for replica and then
box.info.vclock usage. Sometimes box.info.vclock was giving wrong
values. Now it is stable due to improved replica expectation
criterion.

Closes #4508

Closes #4434
Follow-up #4366

@TarantoolBot document
Title: json/msgpack.cfg.encode_deep_as_nil option

Tarantool has several so called serializers to convert data
between Lua and another format: YAML, JSON, msgpack.

YAML is a crazy serializer without depth restrictions. But for
JSON, msgpack, and msgpackffi a user could set encode_max_depth
option. That option led to crop of a table when it had too many
nested levels. Sometimes such behaviour is undesirable.

Now an error is raised instead of data corruption:

    t = nil
    for i = 1, 100 do t = {t} end
    msgpack.encode(t) -- Here an exception is thrown.

To disable it and return the old behaviour back here is a new
option:

    <serializer>.cfg({encode_deep_as_nil = true})

Option encode_deep_as_nil works for JSON, msgpack, and msgpackffi
modules, and is false by default. It means, that now if some
existing users have cropping, even intentional, they will get the
exception.

Tuple is a C library exposed to Lua. In Lua to translate Lua
objects into tuples and back luaL_serializer structure is used.

In Tarantool we have several global serializers, one of which is
for msgpack. Tuples store data in msgpack, and in theory should
have used that global msgpack serializer. But in fact the tuple
module had its own private serializer because of tuples encoding
specifics such as never encode sparse arrays as maps.

This patch makes tuple Lua module use global msgpack serializer
always. But how does tuple handle sparse arrays now? In fact,
the tuple module still has its own serializer, but it is updated
each time when the msgpack serializer is changed.

Part of #4434

Msgpack Lua module is not a simple set of functions. It is a
global serializer object used by plenty of other Lua and C
modules. Msgpack as a serializer can be configured, and in theory
its configuration updates should affect all other modules. For
example, a user could change encode_max_depth:

    require('msgpack').cfg({encode_max_depth = <new_value>})

And that would make tuple:update() accept tables with <new_value>
depth without a crop.

But in fact msgpack configuration didn't affect some places, such
as this one. And all the others who use msgpackffi.

This patch fixes it, for encode_max_depth option. Other options
are still ignored.

Part of #4434

There are some objects called serializers - msgpack, cjson, yaml,
maybe more. They are global objects affecting both Lua and C
modules.

A serializer have settings which can be updated. But before the
patch an update changed only C structure of the serializer. It
made impossible to use settings of the serializers from Lua.

Now any update of any serializer is reflected both in its C and
Lua structures.

Part of #4434