Changes in libcfa/src/concurrency/coroutine.cfa [58b6d1b:76e069f]

File:

• libcfa/src/concurrency/coroutine.cfa (modified) (5 diffs)

libcfa/src/concurrency/coroutine.cfa

@@ -22 +22 @@
 #include <string.h>
 #include <unistd.h>
+// use this define to make unwind.h play nice, definetely a hack
+#define HIDE_EXPORTS
+#include <unwind.h>
+#undef HIDE_EXPORTS
 #include <sys/mman.h>
 }
@@ -29 +33 @@
 #define __CFA_INVOKE_PRIVATE__
 #include "invoke.h"
+
+extern "C" {
+      void _CtxCoroutine_Unwind(struct _Unwind_Exception * storage) __attribute__ ((__noreturn__));
+      static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) __attribute__ ((__noreturn__));
+      static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) {
+            abort();
+      }
+}
 
 //-----------------------------------------------------------------------------
@@ -67 +79 @@
       starter = NULL;
       last = NULL;
-}
-
-void ^?{}(coroutine_desc& this) {}
+      cancellation = NULL;
+}
+
+void ^?{}(coroutine_desc& this) {
+      if(this.state != Halted) {
+            coroutine_desc * src = TL_GET( this_coroutine );
+            coroutine_desc * dst = &this;
+
+            struct _Unwind_Exception storage;
+            storage.exception_class = -1;
+            storage.exception_cleanup = _CtxCoroutine_UnwindCleanup;
+            this.cancellation = &storage;
+            this.last = src;
+
+              // not resuming self ?
+              if ( src == dst ) {
+                      abort( "Attempt by coroutine %.256s (%p) to terminate itself.\n", src->name, src );
+            }
+
+              CoroutineCtxSwitch( src, dst );
+      }
+}
 
 // Part of the Public API
@@ -105 +136 @@
       // Safety note : This could cause some false positives due to preemption
       verify( TL_GET( preemption_state.enabled ) || TL_GET( this_processor )->do_terminate );
+
+      if( unlikely(src->cancellation != NULL) ) {
+            _CtxCoroutine_Unwind(src->cancellation);
+      }
 } //ctxSwitchDirect
 
@@ -162 +197 @@
       }
 
-      void __leave_coroutine(void) {
+      void __leave_coroutine() {
             coroutine_desc * src = TL_GET( this_coroutine ); // optimization
-
-            assertf( src->starter != 0,
+            coroutine_desc * starter = src->cancellation != 0 ? src->last : src->starter;
+
+            src->state = Halted;
+
+            assertf( starter != 0,
                   "Attempt to suspend/leave coroutine \"%.256s\" (%p) that has never been resumed.\n"
                   "Possible cause is a suspend executed in a member called by a coroutine user rather than by the coroutine main.",
                   src->name, src );
-            assertf( src->starter->state != Halted,
+            assertf( starter->state != Halted,
                   "Attempt by coroutine \"%.256s\" (%p) to suspend/leave back to terminated coroutine \"%.256s\" (%p).\n"
                   "Possible cause is terminated coroutine's main routine has already returned.",
-                  src->name, src, src->starter->name, src->starter );
-
-            CoroutineCtxSwitch( src, src->starter );
+                  src->name, src, starter->name, starter );
+
+            CoroutineCtxSwitch( src, starter );
       }
 }