SERVER-17817 Make ServiceContext create and manage Client objects.

Also, deduplicate Client::* method implementations, guard the identity of the
current CurOp of a Client with the Client's _mutex instead of the mutex guarding
the list of all clients.

Makes the currentClient object private to client.cpp, and all access to the
thread-bound client is now done with haveClient() and cc() free functions in the
mongo namespace.

Removes the vesitgal Client::shutdown() methods.

1 files changed, 9 insertions, 34 deletions

diff --git a/src/mongo/db/client.h b/src/mongo/db/client.h
index b01656d3407..f81bc91bf37 100644
--- a/src/mongo/db/client.h
+++ b/src/mongo/db/client.h
@@ -43,6 +43,7 @@
 #include "mongo/db/lasterror.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/operation_context.h"
+#include "mongo/db/service_context.h"
 #include "mongo/platform/unordered_set.h"
 #include "mongo/util/concurrency/spin_lock.h"
 #include "mongo/util/concurrency/threadlocal.h"
@@ -52,21 +53,11 @@ namespace mongo {
     class Collection;
     class AbstractMessagingPort;
 
-    TSP_DECLARE(Client, currentClient)
-
     typedef long long ConnectionId;
 
-    typedef unordered_set<Client*> ClientSet;
-
     /** the database's concept of an outside "client" */
     class Client : public ClientBasic {
     public:
-        // A set of currently active clients along with a mutex to protect the list
-        static boost::mutex clientsMutex;
-        static ClientSet clients;
-
-        ~Client();
-
         /** each thread which does db operations has a Client object in TLS.
          *  call this when your thread starts.
         */
@@ -79,25 +70,12 @@ namespace mongo {
          * Inits a thread if that thread has not already been init'd, setting the thread name to
          * "desc".
          */
-        static void initThreadIfNotAlready(const char* desc) {
-            if (currentClient.get())
-                return;
-            initThread(desc);
-        }
+        static void initThreadIfNotAlready(const char* desc);
 
         /**
          * Inits a thread if that thread has not already been init'd, using the existing thread name
          */
-        static void initThreadIfNotAlready() {
-            if (currentClient.get())
-                return;
-            initThread(getThreadName().c_str());
-        }
-
-        /** this has to be called as the client goes away, but before thread termination
-         *  @return true if anything was done
-         */
-        void shutdown();
+        static void initThreadIfNotAlready();
 
         std::string clientAddress(bool includePort = false) const;
         const std::string& desc() const { return _desc; }
@@ -123,7 +101,8 @@ namespace mongo {
         bool isFromUserConnection() const { return _connectionId > 0; }
 
     private:
-        Client(const std::string& desc,
+        friend class ServiceContext;
+        Client(std::string desc,
                ServiceContext* serviceContext,
                AbstractMessagingPort *p = 0);
 
@@ -141,19 +120,15 @@ namespace mongo {
         mutable SpinLock _lock;
 
         // Whether this client is running as DBDirectClient
-        bool _inDirectClient;
+        bool _inDirectClient = false;
 
         // If != NULL, then contains the currently active OperationContext
-        OperationContext* _txn;
+        OperationContext* _txn = nullptr;
     };
 
     /** get the Client object for this thread. */
-    inline Client& cc() {
-        Client * c = currentClient.get();
-        verify( c );
-        return *c;
-    }
+    Client& cc();
 
-    inline bool haveClient() { return currentClient.get() != NULL; }
+    bool haveClient();
 
 };