Issue:

libgfchangelog.so: cannot open shared object file

Due to hardcoded shared library name runtime loader looks for particular version of
a shared library.

Solution:

Using find_library to locate shared library at runtime solves this issue.

Traceback (most recent call last):
  File "/usr/libexec/glusterfs/python/syncdaemon/gsyncd.py", line 323, in main
    func(args)
  File "/usr/libexec/glusterfs/python/syncdaemon/subcmds.py", line 82, in subcmd_worker
    local.service_loop(remote)
  File "/usr/libexec/glusterfs/python/syncdaemon/resource.py", line 1261, in service_loop
    changelog_agent.init()
  File "/usr/libexec/glusterfs/python/syncdaemon/repce.py", line 233, in __call__
    return self.ins(self.meth, *a)
  File "/usr/libexec/glusterfs/python/syncdaemon/repce.py", line 215, in __call__
    raise res
OSError: libgfchangelog.so: cannot open shared object file: No such file or directory

Change-Id: I3dd013d701ed1cd99ba7ef20d1898f343e1db8f5
fixes: bz#1699394
Signed-off-by: Sunny Kumar <sunkumar@redhat.com>

Some of the scripts that have a #!/usr/bin/python3 shebang do not have a
main() like function. These scripts will not get executed but only
imported. They do not need the shebang.

A few others are not installed with 'make install', but do have a main()
like function. These scripts are expected to be used by developers for
different tasks (mostly code generation). Marking these scripts
executable to make it easier to identify them.

Change-Id: I73541471deb7e0830766b804786244e73dfe4221
Updates: #411
Signed-off-by: Niels de Vos <ndevos@redhat.com>

Change-Id: Ia84cc24c8924e6d22d02ac15f611c10e26db99b4
Signed-off-by: Nigel Babu <nigelb@redhat.com>

see https://review.gluster.org/#/c/19788/,
    https://review.gluster.org/#/c/19871/,
    https://review.gluster.org/#/c/19952/,
    https://review.gluster.org/#/c/20104/,
    https://review.gluster.org/#/c/20162/,
    https://review.gluster.org/#/c/20185/,
    https://review.gluster.org/#/c/20207/,
    https://review.gluster.org/#/c/20227/,
    https://review.gluster.org/#/c/20307/,
    https://review.gluster.org/#/c/20320/,
    https://review.gluster.org/#/c/20332/,
    https://review.gluster.org/#/c/20364/,
    https://review.gluster.org/#/c/20441/, and
    https://review.gluster.org/#/c/20484

shebangs changed from /usr/bin/python2 to /usr/bin/python3.
(Reminder, various distribution packaging guidelines require use
of explicit python version and don't allow '#!/usr/bin/env python',
regardless of how handy that idiom may be.)

glusterfs.spec(.in) package python{2,3}-gluster and python2 or
python3 dependencies as appropriate.

configure(.ac):
+ test for and use python2 or python3 as appropriate. If build
  machine has python2 and python3, use python3. Override by
  setting PYTHON=/usr/bin/python2 when running configure.
+ PYTHONDEV_CPPFLAGS from python[23]-config --includes is a
  better match to the original python sysconfig.get_python_inc().
  All those other extraneous flags breaks the build.
+ Only change the shebangs once. Changing them over and over
  again, e.g., during a `make glusterrpms` in extras/LinuxRPM
  just sends make (is it really make that's looping?) into an
  infinite loop. If you figure out why, let me know.
+ Oldest python2 is python2.6 on CentOS 6 and Debian 8 (Jessie).
  Everything else has 2.7 or 3.x
+ logic from https://review.gluster.org/c/glusterfs/+/21050, which
  needs to be removed/merged after that patch is merged.

Builds on CentOS 6, CentOS 7, Fedora 28, Fedora rawhide, and the
mysterious RHEL > 7.

Change-Id: Idae21d3b6f58b32372e1daa0d234e491e563198f
updates: #411
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>

see https://review.gluster.org/#/c/19788/

use print fn from __future__

Change-Id: If5075d8d9ca9641058fbc71df8a52aa35804cda4
updates: #411
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>

Note 1) we're not supposed to be using #!/usr/bin/env python, see
https://fedoraproject.org/wiki/Packaging:Guidelines?rd=Packaging/Guidelines#Shebang_lines

Note 2) we're also not supposed to be using "!/usr/bin/python,
see https://fedoraproject.org/wiki/Changes/Avoid_usr_bin_python_in_RPM_Build#Quick_Opt-Out

The previous patch (https://review.gluster.org/19767) tried to do too
much in one patch, so it was abandoned.

This patch does two things:
1) minor cleanup of configure(.ac) to explicitly use python2
2) change all the shebang lines to #!/usr/bin/python2 and add them
where they were missing based on warnings emitted during rpmbuild.

In a follow-up patch python2 will eventually be changed to python3.

Before that python2-isms (e.g. print, string.join(), etc.) need to be
converted to python3. Some of those can be rewritten in version agnostic
python. E.g. print statements become print() with "from __future_ import
print_function". The python 2to3 utility will be used for some of those.
Also Aravinda has given guidance in the comments to the first patch for
changes.

updates: #411
Change-Id: I471730962b2526022115a1fc33629fb078b74338
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>

`find_library()` doesn't consider LD_LIBRARY_PATH on Python < 3.6.

Change-Id: Iee26085cb5d14061001f19f032c2664d69a378a8
BUG: 1450593
Signed-off-by: Niklas Hambüchen <mail@nh2.me>

Incorporate the new API 'gf_changelog_init'
introduced in libgfchangelog which should
be called before 'gf_changelog_register'.

Change-Id: I10a9dd5ff3ecc64fd61dcb6b1aa53739e0bdeedd
BUG: 1238063
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-on: http://review.gluster.org/11479
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Venky Shankar <vshankar@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>

[WIP patch as of now, just needs a little tweak]

A pending TODO in the code caused regressions to fail as
bitrot daemons are spawned during volume start (equivalent
to enabling bitrot by default). The problematic part that
casued such failures is during brick disconnections with
unsafe handling of event data structured in the code.

With this patch, data structures are properly cleaned up
with care taken to cleanup all accessors first. This also
fixes potential memory leaks which was bluntly ignored
before.

Change-Id: I70ed82cb1a0fb56c85ef390007e321a97a35c5ce
BUG: 1170075
Signed-off-by: Venky Shankar <vshankar@redhat.com>
original-author: Venky Shankar <vshankar@redhat.com>
Reviewed-on: http://review.gluster.org/9959
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Tested-by: Vijay Bellur <vbellur@redhat.com>

Problem:
libgfchangelog initializes global xlator on library load (via
constructor: _ctor) and mangles it's xlator context thereby
messing with certain important members of the command structure.
On receiving an RPC disconnection event, if the point-of-execution
was in libgfchangelogs context, accessing ->cmd_args during RPC
notify resulted in a segfault.

Fix:
Since the libarary needs to be able to work with processes that
have a notion of an xlator (THIS in particular) and without it,
care needs to be taken to allocate the global xlator when needed.
Moreover, the actual fix is to use the correct xlator context
in both cases. A new API is introduces when needs to be invoked
by the conusmer (although this could have been done during
register() call, keeping it a separate API makes thing flexible
and easy).

Test:
The issue is observed when a brick process goes offline. This is
triggered when test cases (.t's) are run in bulk, since each
test essestially spawns bricks processes (on volume start) and
terminates them (volume stop). Since bitrot daemon, as of now,
spawns upon volume start, the issue is much observed when the
volume is taken offline at the end of each test case. With this
fix, running the basic and core test cases along with building
the linux kernel has passed without daemon segfaults.

Thanks to Johnny (rabhat@) for helping in debugging the issue
(and with the fix :)).

Change-Id: I8d3022bf749590b2ee816504ed9b1dfccc65559a
BUG: 1170075
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-on: http://review.gluster.org/9953
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Tested-by: Vijay Bellur <vbellur@redhat.com>