[PATCH] Shutdown runners

[Amos Jeffries]

This begins the shutdown sequence cleanup by creating a Runners Registry
hook at the begining of the shutdown process.

This registry is for use by components which need to cleanup state or
begin some process which happens during the shutdown_timeout period.

The existing code closing server ports and de-registering authentication
schemes has been converted to runners.

NOTE: There is some doubt over the auth runner, as the state being
closed may still be needed for as yet unprocessed client requests on
existing connections. However this is what the current trunk code does
so have left the behaviour as-is for now.

Amos

=== modified file 'src/auth/Scheme.cc'
--- src/auth/Scheme.cc  2013-10-25 00:13:46 +0000
+++ src/auth/Scheme.cc  2014-01-13 01:09:50 +0000
@@ -35,6 +35,7 @@
 #include "auth/Config.h"
 #include "auth/Gadgets.h"
 #include "auth/Scheme.h"
+#include "base/RunnersRegistry.h"
 #include "globals.h"
 
 Vector<Auth::Scheme::Pointer> *Auth::Scheme::_Schemes = NULL;
@@ -90,3 +91,11 @@
         scheme->shutdownCleanup();
     }
 }
+
+class AuthShutdownRr : public RegisteredRunner
+{
+public:
+    // XXX: make this depend on the server ports being closed and no client 
connections open
+    virtual void run(const RunnerRegistry &) {Auth::Scheme::FreeAll();}
+};
+RunnerRegistrationEntry(rrShutdown, AuthShutdownRr);

=== modified file 'src/base/RunnersRegistry.h'
--- src/base/RunnersRegistry.h  2012-08-28 13:00:30 +0000
+++ src/base/RunnersRegistry.h  2014-01-12 22:38:29 +0000
@@ -37,6 +37,10 @@
     /// modules and features based on the finalized configuration.
     rrAfterConfig,
 
+    /// Managed by main.cc. Activated after receiving the shutdown signal
+    /// and deactivated before exit()-ing.
+    rrShutdown,
+
     rrEnd ///< not a real registry, just a label to mark the end of enum
 } RunnerRegistry;
 

=== modified file 'src/main.cc'
--- src/main.cc 2014-01-12 17:51:12 +0000
+++ src/main.cc 2014-01-14 23:14:31 +0000
@@ -259,24 +259,27 @@
 void
 SignalEngine::doShutdown(time_t wait)
 {
+    shutting_down = 1;
+
     debugs(1, DBG_IMPORTANT, "Preparing for shutdown after " << 
statCounter.client_http.requests << " requests");
     debugs(1, DBG_IMPORTANT, "Waiting " << wait << " seconds for active 
connections to finish");
 
-    shutting_down = 1;
-
+    eventAdd("SquidShutdown", &StopEventLoop, this, (double) (wait + 1), 1, 
false);
 #if USE_WIN32_SERVICE
     WIN32_svcstatusupdate(SERVICE_STOP_PENDING, (wait + 1) * 1000);
 #endif
 
-    /* run the closure code which can be shared with reconfigure */
-    serverConnectionsClose();
-#if USE_AUTH
-    /* detach the auth components (only do this on full shutdown) */
-    Auth::Scheme::FreeAll();
-#endif
-    eventAdd("SquidShutdown", &StopEventLoop, this, (double) (wait + 1), 1, 
false);
+    ActivateRegistered(rrShutdown);
 }
 
+/// close the server listening ports when shutting down
+class ServerPortsShutdownRr : public RegisteredRunner
+{
+public:
+    virtual void run(const RunnerRegistry &) {serverConnectionsClose();}
+};
+RunnerRegistrationEntry(rrShutdown, ServerPortsShutdownRr);
+
 static void
 usage(void)
 {
@@ -1809,6 +1812,7 @@
             DeactivateRegistered(rrAfterConfig);
             DeactivateRegistered(rrClaimMemoryNeeds);
             DeactivateRegistered(rrFinalizeConfig);
+            DeactivateRegistered(rrShutdown);
             enter_suid();
 
             if (TheKids.someSignaled(SIGINT) || TheKids.someSignaled(SIGTERM)) 
{
@@ -1907,6 +1911,8 @@
     DeactivateRegistered(rrAfterConfig);
     DeactivateRegistered(rrClaimMemoryNeeds);
     DeactivateRegistered(rrFinalizeConfig);
+    DeactivateRegistered(rrShutdown);
+
 #if LEAK_CHECK_MODE && 0 /* doesn't work at the moment */
 
     configFreeMemory();