Add class cycle detection during unmarshaling (#946)

Add support for detection of class cycles during unmarshaling in
languages which do no have garbage collection: C++, Swift, and Objective-C.
A `MarshalException` is thrown when a cycle is detected.

The property `Ice.AcceptClassCycles` can be set to a value greater than `0`
to change this behavior.

14 files changed, 52 insertions, 2 deletions

diff --git a/cpp/test/Ice/objects/AllTests.cpp b/cpp/test/Ice/objects/AllTests.cpp
index 65134a2c49e..c84b73d51a9 100644
--- a/cpp/test/Ice/objects/AllTests.cpp
+++ b/cpp/test/Ice/objects/AllTests.cpp
@@ -604,5 +604,25 @@ allTests(Test::TestHelper* helper)
     }
     cout << "ok" << endl;
 
+    cout << "testing sending class cycle... " << flush;
+    {
+        RecursivePtr rec = ICE_MAKE_SHARED(Recursive);
+        rec->v = rec;
+        bool acceptsCycles = initial->acceptsClassCycles();
+        try
+        {
+            initial->setCycle(rec);
+            test(acceptsCycles);
+        }
+        catch(const Ice::UnknownLocalException&)
+        {
+            // expected when the remote server does not accept cycles
+            // and throws a MarshalException
+            test(!acceptsCycles);
+        }
+        rec->v = ICE_NULLPTR;
+    }
+    cout << "ok" << endl;
+
     return initial;
 }
diff --git a/cpp/test/Ice/objects/Client.cpp b/cpp/test/Ice/objects/Client.cpp
index 4d5dc868b83..a27c51e17f6 100644
--- a/cpp/test/Ice/objects/Client.cpp
+++ b/cpp/test/Ice/objects/Client.cpp
@@ -118,7 +118,7 @@ void
 Client::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
-
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/objects/Collocated.cpp b/cpp/test/Ice/objects/Collocated.cpp
index eb4434fbe39..0633cfa5d13 100644
--- a/cpp/test/Ice/objects/Collocated.cpp
+++ b/cpp/test/Ice/objects/Collocated.cpp
@@ -110,6 +110,7 @@ void
 Collocated::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/objects/Test.ice b/cpp/test/Ice/objects/Test.ice
index 38214e39951..a89b9beb0e8 100644
--- a/cpp/test/Ice/objects/Test.ice
+++ b/cpp/test/Ice/objects/Test.ice
@@ -222,6 +222,9 @@ interface Initial
     void setRecursive(Recursive p);
     bool supportsClassGraphDepthMax();
 
+    void setCycle(Recursive r);
+    bool acceptsClassCycles();
+
     ["marshaled-result"] B getMB();
     ["amd", "marshaled-result"] B getAMDMB();
 
diff --git a/cpp/test/Ice/objects/TestI.cpp b/cpp/test/Ice/objects/TestI.cpp
index 9cfd4c395eb..abf4154e59e 100644
--- a/cpp/test/Ice/objects/TestI.cpp
+++ b/cpp/test/Ice/objects/TestI.cpp
@@ -187,6 +187,20 @@ InitialI::supportsClassGraphDepthMax(const Ice::Current&)
     return true;
 }
 
+void
+InitialI::setCycle(ICE_IN(RecursivePtr) r, const Ice::Current&)
+{
+    // break the cycle
+    assert(r);
+    r->v = ICE_NULLPTR;
+}
+
+bool
+InitialI::acceptsClassCycles(const Ice::Current& c)
+{
+    return c.adapter->getCommunicator()->getProperties()->getPropertyAsInt("Ice.AcceptClassCycles") > 0;
+}
+
 #ifdef ICE_CPP11_MAPPING
 InitialI::GetMBMarshaledResult
 InitialI::getMB(const Ice::Current& current)
diff --git a/cpp/test/Ice/objects/TestI.h b/cpp/test/Ice/objects/TestI.h
index 3b265a19664..78874dbb91b 100644
--- a/cpp/test/Ice/objects/TestI.h
+++ b/cpp/test/Ice/objects/TestI.h
@@ -93,6 +93,9 @@ public:
     virtual void setRecursive(ICE_IN(Test::RecursivePtr), const Ice::Current&);
     virtual bool supportsClassGraphDepthMax(const Ice::Current&);
 
+    virtual void setCycle(ICE_IN(Test::RecursivePtr), const Ice::Current&);
+    virtual bool acceptsClassCycles(const Ice::Current&);
+
 #ifdef ICE_CPP11_MAPPING
     virtual GetMBMarshaledResult getMB(const Ice::Current&);
     virtual void getAMDMBAsync(std::function<void(const GetAMDMBMarshaledResult&)>,
diff --git a/cpp/test/Ice/optional/AllTests.cpp b/cpp/test/Ice/optional/AllTests.cpp
index 7b00e0a421c..369d2228cc6 100644
--- a/cpp/test/Ice/optional/AllTests.cpp
+++ b/cpp/test/Ice/optional/AllTests.cpp
@@ -587,6 +587,7 @@ allTests(Test::TestHelper* helper, bool)
 
     mo1->k = mo1;
     MultiOptionalPtr mo5 = ICE_DYNAMIC_CAST(MultiOptional, initial->pingPong(mo1));
+
     test(mo5->a == mo1->a);
     test(mo5->b == mo1->b);
     test(mo5->c == mo1->c);
diff --git a/cpp/test/Ice/optional/Client.cpp b/cpp/test/Ice/optional/Client.cpp
index 1f2bb2edb45..4806e2f02cf 100644
--- a/cpp/test/Ice/optional/Client.cpp
+++ b/cpp/test/Ice/optional/Client.cpp
@@ -20,6 +20,7 @@ void
 Client::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/optional/Server.cpp b/cpp/test/Ice/optional/Server.cpp
index f526d0355d9..a84d6694b7e 100644
--- a/cpp/test/Ice/optional/Server.cpp
+++ b/cpp/test/Ice/optional/Server.cpp
@@ -20,6 +20,7 @@ void
 Server::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/optional/ServerAMD.cpp b/cpp/test/Ice/optional/ServerAMD.cpp
index bdc012694ce..f9d16fed20f 100644
--- a/cpp/test/Ice/optional/ServerAMD.cpp
+++ b/cpp/test/Ice/optional/ServerAMD.cpp
@@ -19,6 +19,7 @@ void
 ServerAMD::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/slicing/objects/Client.cpp b/cpp/test/Ice/slicing/objects/Client.cpp
index 537d7e9d216..b9f217e495d 100644
--- a/cpp/test/Ice/slicing/objects/Client.cpp
+++ b/cpp/test/Ice/slicing/objects/Client.cpp
@@ -23,6 +23,7 @@ Client::run(int argc, char** argv)
     //
     // For this test, we enable object collection.
     //
+    properties->setProperty("Ice.AcceptClassCycles", "1");
     properties->setProperty("Ice.CollectObjects", "1");
 
     Ice::CommunicatorHolder communicator = initialize(argc, argv, properties);
diff --git a/cpp/test/Ice/slicing/objects/Server.cpp b/cpp/test/Ice/slicing/objects/Server.cpp
index f1cd93e6ae3..b7ca13be31b 100644
--- a/cpp/test/Ice/slicing/objects/Server.cpp
+++ b/cpp/test/Ice/slicing/objects/Server.cpp
@@ -19,6 +19,7 @@ void
 Server::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/slicing/objects/ServerAMD.cpp b/cpp/test/Ice/slicing/objects/ServerAMD.cpp
index ab4df8a0f5e..e7e60f6998f 100644
--- a/cpp/test/Ice/slicing/objects/ServerAMD.cpp
+++ b/cpp/test/Ice/slicing/objects/ServerAMD.cpp
@@ -19,6 +19,7 @@ void
 ServerAMD::run(int argc, char** argv)
 {
     Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
 #ifndef ICE_CPP11_MAPPING
     properties->setProperty("Ice.CollectObjects", "1");
 #endif
diff --git a/cpp/test/Ice/stream/Client.cpp b/cpp/test/Ice/stream/Client.cpp
index 23a2be692df..879b93ffb61 100644
--- a/cpp/test/Ice/stream/Client.cpp
+++ b/cpp/test/Ice/stream/Client.cpp
@@ -1365,7 +1365,9 @@ public:
 void
 Client::run(int argc, char** argv)
 {
-    Ice::CommunicatorHolder communicator = initialize(argc, argv);
+    Ice::PropertiesPtr properties = createTestProperties(argc, argv);
+    properties->setProperty("Ice.AcceptClassCycles", "1");
+    Ice::CommunicatorHolder communicator = initialize(argc, argv, properties);
     void allTests(Test::TestHelper*);
     allTests(this);
 }