The sqlVdbeMemIntegerify() function accepts the is_forced flag as
one of the arguments. But this flag is actually useless, because
regardless of whether it is TRUE or FALSE, the function will do
the same. This patch removes the is_forced argument from the
function. There will be no test, since the result of the function
has not changed.

Part of #4526

According to code coio_call does not take a timeout as an argument,
however it was mentioned in the comment and usage example. This lead to
error in documentation. The patch fixes it.

Closes #4663

C functions are loaded from .so/.dylib dynamic libraries. A
library is loaded when any function from there is called first
time. And was supposed to be unloaded, when all its functions are
dropped from the schema (box.schema.func.drop()), and none of them
is still in a call. But the unloading part was broken.

In fact, box.schema.func.drop() never unloaded anything. Moreover,
when functions from the module were added again without a restart,
it led to a second mmap of the same module. And so on, the same
library could be loaded any number of times.

The problem was in a useless flag in struct module preventing its
unloading even when it is totally unused. It is dropped.

Closes #4648

Error injections are used to simulate an error. They are
represented as a flag, or a number, and are used in Lua tests. But
they don't have any feedback. That makes impossible to use the
injections to check that something has happened. Something very
needed to be checked, and impossible to check in a different way.

More certainly, the patch is motivated by a necessity to count
loaded dynamic libraries to ensure, that they are loaded and
unloaded when expected. This is impossible to do in a platform
independent way. But an error injection as a debug-only counter
would solve the problem.

Needed for #4648

There is a bug in XCode 11 which makes some standard C headers
not self sufficient when compile with gcc. At least <stdlib.h> and
<algorithm> are affected. When they are included first,
compilation fails with creepy errors like this:

    In file included
    from /Applications/Xcode.app/Contents/Developer/
        Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/
        sys/wait.h:110,
    from /Applications/Xcode.app/Contents/Developer/
        Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/
        stdlib.h:66,
    from tarantool/third_party/zstd/lib/common/zstd_common.c:16:
        /Applications/Xcode.app/Content/Developer/
        Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/
        sys/resource.h:
    In function 'getiopolicy_np': /Applications/Xcode.app/Contents/Developer/
        Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/
        sys/resource.h:447:34: error:
            expected declaration specifiers before '__OSX_AVAILABLE_STARTING'
            447 | int     getiopolicy_np(int, int)
            __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_2_0);

The patch workarounds the bug by deleting the buggy header
includes where possible, and by changing include order in other
cases.

Also there was a second compilation problem. This was about
different definitions of the same standard functions: via extern
"C" and without. It looked like this:

    In file included from tarantool/src/trivia/util.h:36,
    from tarantool/src/tt_pthread.h:35,
    from tarantool/src/lib/core/fiber.h:38,
    from tarantool/src/lib/core/coio.h:33,
    from tarantool/src/lib/core/coio.cc:31:
    /usr/local/Cellar/gcc/9.2.0_1/lib/gcc/9/gcc/x86_64-apple-darwin18/9.2.0
    include-fixed/stdio.h:222:7: error: conflicting declaration of
    'char* ctermid(char*)' with 'C' linkage
      222 | char *ctermid(char *);
          |       ^~~~~~~

    In file included from /Applications/Xcode.app/Contents/Developer/Platforms/
    MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/unistd.h:525,
    from tarantool/src/lib/core/fiber.h:37,
    from tarantool/src/lib/core/coio.h:33,
    from tarantool/src/lib/core/coio.cc:31:
    /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/
    Developer/SDKs/MacOSX.sdk/usr/include/_ctermid.h:26:10: note: previous
    declaration with 'C++' linkage
      26 | char    *ctermid(char *);
         |          ^~~~~~~

This bug is workarounded by deletion of the conflicting includes,
because anyway they appeared to be not needed.

Closes #4580

Conflicts:
	third_party/decNumber

New commit fixes build on XCode 11.

snrpintf always null-terminates the passed string, and it also returns
the number of bytes that "would have been written if there was enough
space", so not only we don't have to null-terminate the string, but even
more so we shouldn't do it erroneously. The only case when a string
should be null-terminated manually is when the print cycle doesn't run
at all, so move the termination before the cycle.

Closes #4636

The tarantool_free() call in the end of main() works all the time except
when we exit due to a panic. We need to clear terminal state in this
case also, so return to using atexit() to clear readline state.

Closes #4466

Unicode_ci collation breaks the general
rule for objects naming, so we remove it
in version 2.3.1

Closes #4561

After the commit 77fa45bd
('lua: add fiber.top() listing fiber cpu consumption')
the unit tests builds failed like:

/opt/rh/devtoolset-6/root/usr/libexec/gcc/x86_64-redhat-linux/6.3.1/ld:
  ../../src/lib/core/libcore.a(fiber.c.o): undefined reference to symbol
  'clock_gettime@@GLIBC_2.2.5'
//lib64/librt.so.1: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
test/unit/CMakeFiles/cbus.test.dir/build.make:108: recipe for target
  'test/unit/cbus.test' failed
make[2]: *** [test/unit/cbus.test] Error 1

Found that fiber.cc is using now clock_gettime(), which requires -lrt
with glibc. To fix it added librt dependency for core library for glibc.
Due to glibc requires for -lrt for clock_gettime() only for some
versions, check 'man clock_gettime.2':
  'Link with -lrt (only for glibc versions before 2.17).'
the check whether is able to use clock_gettime() w/o librt library is
added.

Close #4639

(cherry picked from commit 99b0ef771135eab66ef3758371b1b5431e21cbff)

It was requested to be raised from 32 to 128

Closes #4670

The problem was in that the test uses the global trigger
box.session.on_disconnect() to set a global variable by one
connection. But test-run can do multiple connects/reconnects to
the same instance. That led to multiple invocations of
box.session.on_disconnect(), which could override the global
variable in unexpected ways and moments.

The patch makes only one session execute that trigger.

Probably related to https://github.com/tarantool/test-run/issues/46


Follow up #4627

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

List of changes
     - fold: keep type of emitted CONV in sync with its mode
     - test: adjust the test name related to PAIRSMM flag

Turns on LUAJIT_ENABLE_PAIRSMM flag for tarantool build.
Now __pairs/__ipairs metamethods are available.

Closes #4650

Added build + test jobs in GitLab-CI and build + test + deploy jobs on
Travis-CI for Fedora 31.

Updated testing dependencies in the RPM spec to follow the new Python 2
package naming scheme that was introduced in Fedora 31: it uses
python2-' prefix rather then 'python-'.

Fedora 31 does not provide python2-gevent and python2-greenlet packages,
so they were pushed to https://packagecloud.io/packpack/backports
repository. This repository is enabled in our build image
(packpack/packpack:fedora-31) by default. Those dependencies are build-time,
so nothing was changed for a user. The source RPM packages were gathered
from https://rpms.remirepo.net/rpmphp/

.

Closes #4612

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

Strengthen test_run:cmd() against temporary connection failures (#193).

We recently added 'replication/box_set_replication_stress' test that may
exceed file descriptor limit. When test_run:cmd() function executes a
command ('switch master' in the case), it tries to create a new socket
and connect it to test-run's inspector, but it may fail to do so in the
case, because of the file descriptor limit.

The sockets that the test produces are closed in background, so if we'll
keep trying to create and connect a socket we'll succeed once. This is
exactly that the test-run's patch doing: it fails test_run:cmd()
function only if a socket cannot be connected during 100 seconds.

I guess that the reason why sockets are not closed immediately is that
relays wait until replicas will close its side of a socket and only then
closes its side. Didn't investigate it deeper, to be honest.

Inside json_decode() struct luaL_serializer is allocated on stack, but
json context stores pointer to it:

   998	static int json_decode(lua_State *l)
   999	{
  ...
  1007	    if (lua_gettop(l) == 2) {
  1008	        struct luaL_serializer user_cfg = *luaL_checkserializer(l);
  1009	        luaL_serializer_parse_options(l, &user_cfg);
  1010	        lua_pop(l, 1);
  1011	        json.cfg = &user_cfg;
  1012      }

Later (for instance in json_decode_descend()), it can be dereferenced
which in turn results in stack-use-after-scope (object turns into
garbage right after scope is ended). To fix it let's simply avoid
allocating and copying luaL_serializer on stack and instead use pointer
to it.

Bug is found by ASAN: test app-tap/json.test.lua fails with enabled
ASAN. Current fix allows to pass all tests.

Thanks to @Korablev77 for the initial investigation.

Closes #4637

This reverts commit a0b196dd.

This commit was pushed occasionally and points to a draft commit in
test-run repository. See also
https://github.com/tarantool/test-run/issues/195

There were some pass conditions in quorum test which could take some
time to be satisfied. Now they are wrapped using test_run:wait_cond to
make the test stable.

Closes #4586

In replicaset_follow we iterate anon replicas list: list of replicas
that haven't received an UUID. In case of successful connect replica
link is being removed from anon list. If it happens immediately,
without yield in applier, iteration breaks. Now it is fixed by
rlist_foreach_entry_safe instead of common rlist_foreach_entry.
Relevant test case is added.

Part of #4586
Closes #4576
Closes #4440

During pruning of appliers some anon replicas might connect
from replicaset_follow called in another fiber. Therefore we need to
prune appliers of anon replicas first and, moreover, prune them one by
one instead of iterating them, as far as any of them might connect
while we are stopping the other one and it will break iteration.

Part of #4586
Closes #4643

Stabilize tcp_connect in test_run:cmd() (tarantool/test-run#193)

Triggers don't throw exceptions any more. Now they have
return codes to report errors.

Closes #4247

Since refactoring: clear privilege managing triggers from exceptions
(977fca29) we are doing zero memset for
trigger struct in txn_alter_trigger_new. This means we don't any more
need to set any field of this struct to NULL explicitly. 

Part of #4247

Originally index_def_check_tuple comment said that it throws a nice
error. Since refactoring: remove exceptions from
index_def_new_from_tuple (90ac0037)
it returns an error. Now it is clearly specified in the comment.

Part of #4247

Clear triggers from freshly occured exceptions. Trivial replacements:
`diag_raise` by `return -1`, _xc function by it's non _xc version.

Part of #4247

In refactoring: use non _xc version of functions in triggers
(b75d5f85) sequence_cache_find was
replaced by sequence_by_id. It led to the loss of diagnostics in case
of sequence_by_id failure. Now it is fixed.

Part of #4247

Some error conditions in triggers and underlying functions were
combined to look better. On the other hand, in
on_replace_dd_fk_constraint we now return an error immediately if
child space were not found instead of searching for both child and
parent spaces before search results inspection.

Part of #4247

In case of allocation problems in region alloc we were setting
diagnostics using "new slab" stub. Now we specify concrete struct name
which was going to be allocated.

Part of #4247

std operator new might throw so we need to wrap it in triggers to
provide non-throwing triggers. It also means alter_space_move_indexes
returns an error code now. It's usages are updated.

Part of #4247

Some time ago, when there was no support of boolean type in SQL, boolean
values passed as parameters to be bound were converted to integer values
0 and 1. It takes place in lua_sql_bind_decode(). However, now we can
avoid this conversion and store booleans as booleans. Note that patch
does not include test case since type of value is preserved correctly,
so when binding is extracted from struct sql_bind it will assigned to
the right value.

Binary session disconnect trigger yield could lead to use after
free of the session object. That happened because iproto thread
sent two requests to TX thread at disconnect:

    - Close the session and run its on disconnect triggers;

    - If all requests are handled, destroy the session.

When a connection is idle, all requests are handled, so both these
requests are sent. If the first one yielded in TX thread, the
second one arrived and destroyed the session right under the feet
of the first one.

This can be solved in two ways - in TX thread, and in iproto
thread.

Iproto thread solution (which is chosen in the patch): just don't
send destroy request until disconnect returns back to iproto
thread.

TX thread solution (alternative): add a flag which says whether
disconnect is processed by TX. When destroy request arrives, it
checks the flag. If disconnect is not done, the destroy request
waits on a condition variable until it is.

The iproto is a bit tricker to implement, but it looks more
correct.

Closes #4627

Add LUAJIT_ENABLE_PAIRSMM flag as a build option for luajit.
If the flag is set, pairs/ipairs metamethods are available in
Lua 5.1.
For Tarantool this option is enabled by default.

The warning is observed when tarantool is compiled by GCC 9.1.0.

Warnings are treated as errors during a debug build or when
-DENABLE_WERROR=ON option is passed to cmake, that is usual for our
testing jobs in CI.

The commit that introduces the problem is
3a8adccf ('access: fix invalid error
type for not found user').

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

Replication's applier encoded an auth request with exactly the
same parameters as extracted by the URI parser. I.e. when no
password was specified, the parser returned it as NULL, and it was
not encoded. The relay, received such an auth request, complained
that IPROTO_TUPLE field is not specified (this is password).

Such an error confuses - a user didn't do anything illegal, he
just used URI like 'login@host:port', without a password after the
login.

The patch makes the applier use an empty string as a default
password.

An alternative was to force a user always set a password even if
it is an empty string, like that: 'login:@host:port'. And if a
password was not found in an auth request, then reject it with a
password mismatch error. But in that case a URI of kind
'login@host:port' becomes useless - it can never pass. In
addition, netbox already uses an empty string as a default
password. So the only way to make it consistent, and don't break
anything - repeat netbox logic for replication URIs.

Closes #4605

Conflicts:
	test/replication/suite.cfg

Box.info.replication shows applier/relay's latest error message.
But it didn't include errno description for system errors, even
though it was included in the logs. Now box.info shows the errno
description as well, when possible.

Closes #4402

Conflicts:
	test/replication/suite.cfg

The only error type having an errno as a part of it was
SystemError (and its descendants SocketError, TimedOut, OOM, ...).
That was used in logs (SystemError::log() method), and exposed to
Lua (if type was SystemError, an error object had 'errno' field).

But actually errno might be useful not only there. For example,
box.info.replication exposes the latest error message of
applier/relay as 'message' field of 'upstream/downstream' fields,
lacking errno description.

Before the patch it was impossible to obtain an errno code from C,
because it was necessary to check whether an error has SystemError
type, cast to SystemError class, and call SystemError::get_errno()
method.

Now errno is available as a part of struct error object (available
from C), and is not 0 for system errors.

Part of #4402

Box.session.su() raised 'SystemError' when a user was not found
due to a too long user name. That was obviously wrong, because
SystemError is always something related to libraries (standard,
curl, etc), and it has an errno code.

Now a ClientError is raised.

Functions are stored in lists inside module objects. Module
objects are stored in a hash table, where key is a package name.
But the key was a pointer at one of module's function definition
object. Therefore, when that function was deleted, its freed
package name memory was still in the hash key, and could be
accessed, when another function was deleted.

Now module does not use memory of its functions, and keep a copy
of the package name.

fiber.top() fills in statistics every event loop iteration,
so if it was just enabled, fiber.top() returns zero in fiber cpu
usage statistics because total time consumed by the main thread was
not yet accounted for.
Same stands for viewing top() results for a freshly created fiber:
its metrics will be zero since it hasn't lived a full ev loop iteration
yet.
Fix this by delaying the test till top() results are meaningful and add
minor refactoring.

Follow-up #2694