SERVER-27211 de-duplicate symbol `isMongos`

A hidden global variable representing the "is Mongos process" state
can now be accessed and updated by the `is_mongos.h` interface.  All
tests defining their own versions (and test crutches) are replaced
with calls to global registration of the desired state of this variable.
The `mongos` main executable now sets this hidden global state as part
of its startup code.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/mongo/s/server.cpp b/src/mongo/s/server.cpp
index 44569f4081a..2bad7e6063f 100644
--- a/src/mongo/s/server.cpp
+++ b/src/mongo/s/server.cpp
@@ -73,6 +73,7 @@
 #include "mongo/s/commands/request.h"
 #include "mongo/s/config.h"
 #include "mongo/s/grid.h"
+#include "mongo/s/is_mongos.h"
 #include "mongo/s/mongos_options.h"
 #include "mongo/s/query/cluster_cursor_cleanup_job.h"
 #include "mongo/s/query/cluster_cursor_manager.h"
@@ -435,6 +436,7 @@ MONGO_INITIALIZER_GENERAL(setSSLManagerType, MONGO_NO_PREREQUISITES, ("SSLManage
 #endif
 
 int mongoSMain(int argc, char* argv[], char** envp) {
+    mongo::setMongos();
     static StaticObserver staticObserver;
     if (argc < 1)
         return EXIT_FAILURE;