common,test: g_ceph_context->put() upon return

prior to this change, global_init() could create a new CephContext
and assign it to g_ceph_context. it's our responsibilty to release
the CephContext explicitly using cct->put() before the application
quits. but sometimes, we fail to do so.

in this change, global_init() will return an intrusive_ptr<CephContext>,
which calls `g_ceph_context->put()` in its dtor. this ensures that
the CephContext is always destroyed before main() returns. so the
log is flushed before _log_exp_length is destroyed.

there are two cases where global_pre_init() is called directly.
- ceph_conf.cc: g_ceph_context->put() will be called by an intrusive_ptr<>
  deleter.
- rgw_main.cc: global_init() is called later on on the success code
  path, so it will be taken care of.

Fixes: http://tracker.ceph.com/issues/17762
Signed-off-by: Kefu Chai <kchai@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/test/filestore/TestFileStore.cc b/src/test/filestore/TestFileStore.cc
index a100a5f3a69..6d857be4116 100644
--- a/src/test/filestore/TestFileStore.cc
+++ b/src/test/filestore/TestFileStore.cc
@@ -68,7 +68,8 @@ int main(int argc, char **argv) {
   vector<const char*> args;
   argv_to_vec(argc, (const char **)argv, args);
 
-  global_init(NULL, args, CEPH_ENTITY_TYPE_CLIENT, CODE_ENVIRONMENT_UTILITY, 0);
+  auto cct = global_init(NULL, args, CEPH_ENTITY_TYPE_CLIENT,
+			 CODE_ENVIRONMENT_UTILITY, 0);
   common_init_finish(g_ceph_context);
   g_ceph_context->_conf->set_val("osd_journal_size", "100");
   g_ceph_context->_conf->apply_changes(NULL);