treewide: Follow rule of five

Good to explicitly declare things to not accidentally do twice the work by
preventing that kind of misuse.
This is essentially just cppcoreguidelines-special-member-functions lint
in clang-tidy.

src/libexpr/eval.cc

@@ -741,6 +741,11 @@ public:
         inDebugger = true;
     }
 
+    DebuggerGuard(DebuggerGuard &&) = delete;
+    DebuggerGuard(const DebuggerGuard &) = delete;
+    DebuggerGuard & operator=(DebuggerGuard &&) = delete;
+    DebuggerGuard & operator=(const DebuggerGuard &) = delete;
+
     ~DebuggerGuard()
     {
         inDebugger = false;

src/libexpr/include/nix/expr/attr-set.hh

@@ -107,6 +107,8 @@ private:
     Bindings & operator=(const Bindings &) = delete;
     Bindings & operator=(Bindings &&) = delete;
 
+    ~Bindings() = default;
+
     friend class BindingsBuilder;
 
     /**

src/libexpr/include/nix/expr/value.hh

@@ -164,8 +164,6 @@ public:
     Value ** elems;
     ListBuilder(EvalMemory & mem, size_t size);
 
-    // NOTE: Can be noexcept because we are just copying integral values and
-    // raw pointers.
     ListBuilder(ListBuilder && x) noexcept
         : size(x.size)
         , inlineElems{x.inlineElems[0], x.inlineElems[1]}
@@ -173,6 +171,11 @@ public:
     {
     }
 
+    ListBuilder(const ListBuilder &) = delete;
+    ListBuilder & operator=(ListBuilder &&) = delete;
+    ListBuilder & operator=(const ListBuilder &) = delete;
+    ~ListBuilder() = default;
+
     Value *& operator[](size_t n)
     {
         return elems[n];

src/libstore/include/nix/store/pathlocks.hh

@@ -61,6 +61,10 @@ struct FdLock
     bool acquired = false;
 
     FdLock(Descriptor desc, LockType lockType, bool wait, std::string_view waitMsg);
+    FdLock(const FdLock &) = delete;
+    FdLock & operator=(const FdLock &) = delete;
+    FdLock(FdLock &&) = delete;
+    FdLock & operator=(FdLock &&) = delete;
 
     ~FdLock()
     {

src/libutil/include/nix/util/serialise.hh

@@ -159,6 +159,8 @@ struct FdSink : BufferedSink
     }
 
     FdSink(FdSink &&) = default;
+    FdSink(const FdSink &) = delete;
+    FdSink & operator=(const FdSink &) = delete;
 
     FdSink & operator=(FdSink && s)
     {
@@ -200,8 +202,10 @@ struct FdSource : BufferedSource, RestartableSource
     }
 
     FdSource(FdSource &&) = default;
-
     FdSource & operator=(FdSource && s) = default;
+    FdSource(const FdSource &) = delete;
+    FdSource & operator=(const FdSource & s) = delete;
+    ~FdSource() = default;
 
     bool good() override;
     void restart() override;
@@ -452,6 +456,11 @@ struct LambdaSink : Sink
     {
     }
 
+    LambdaSink(LambdaSink &&) = delete;
+    LambdaSink(const LambdaSink &) = delete;
+    LambdaSink & operator=(LambdaSink &&) = delete;
+    LambdaSink & operator=(const LambdaSink &) = delete;
+
     ~LambdaSink()
     {
         cleanupFun();
@@ -628,6 +637,11 @@ struct FramedSource : Source
     {
     }
 
+    FramedSource(FramedSource &&) = delete;
+    FramedSource(const FramedSource &) = delete;
+    FramedSource & operator=(FramedSource &&) = delete;
+    FramedSource & operator=(const FramedSource &) = delete;
+
     ~FramedSource()
     {
         try {
@@ -685,6 +699,11 @@ struct FramedSink : nix::BufferedSink
     {
     }
 
+    FramedSink(FramedSink &&) = delete;
+    FramedSink(const FramedSink &) = delete;
+    FramedSink & operator=(FramedSink &&) = delete;
+    FramedSink & operator=(const FramedSink &) = delete;
+
     ~FramedSink()
     {
         try {

src/libutil/include/nix/util/sync.hh

@@ -69,13 +69,10 @@ public:
         {
         }
     public:
-        Lock(Lock && l)
+        Lock(Lock && l) = delete;
-            : s(l.s)
-        {
-            unreachable();
-        }
-
         Lock(const Lock & l) = delete;
+        Lock & operator=(Lock && l) = delete;
+        Lock & operator=(const Lock & l) = delete;
 
         ~Lock() {}
 
@@ -110,6 +107,8 @@ public:
 
     struct WriteLock : Lock<WL>
     {
+        using Lock<WL>::Lock;
+
         T * operator->()
         {
             return &WriteLock::s->data;
@@ -131,6 +130,8 @@ public:
 
     struct ReadLock : Lock<RL>
     {
+        using Lock<RL>::Lock;
+
         const T * operator->()
         {
             return &ReadLock::s->data;

src/libutil/include/nix/util/util.hh

@@ -384,6 +384,11 @@ struct MaintainCount
         counter += delta;
     }
 
+    MaintainCount(MaintainCount &&) = delete;
+    MaintainCount(const MaintainCount &) = delete;
+    MaintainCount & operator=(MaintainCount &&) = delete;
+    MaintainCount & operator=(const MaintainCount &) = delete;
+
     ~MaintainCount()
     {
         counter -= delta;

src/libutil/include/nix/util/xml-writer.hh

@@ -50,6 +50,11 @@ public:
         writer.openElement(name, attrs);
     }
 
+    XMLOpenElement(XMLOpenElement &&) = delete;
+    XMLOpenElement(const XMLOpenElement &) = delete;
+    XMLOpenElement & operator=(XMLOpenElement &&) = delete;
+    XMLOpenElement & operator=(const XMLOpenElement &) = delete;
+
     ~XMLOpenElement()
     {
         writer.closeElement();

src/libutil/unix/include/nix/util/monitor-fd.hh

@@ -27,6 +27,10 @@ private:
 
 public:
     MonitorFdHup(int fd);
+    MonitorFdHup(MonitorFdHup &&) = delete;
+    MonitorFdHup(const MonitorFdHup &) = delete;
+    MonitorFdHup & operator=(MonitorFdHup &&) = delete;
+    MonitorFdHup & operator=(const MonitorFdHup &) = delete;
 
     ~MonitorFdHup()
     {

src/libutil/unix/signals.cc

@@ -141,6 +141,16 @@ struct InterruptCallbackImpl : InterruptCallback
 {
     InterruptCallbacks::Token token;
 
+    InterruptCallbackImpl(InterruptCallbacks::Token token)
+        : token(token)
+    {
+    }
+
+    InterruptCallbackImpl(InterruptCallbackImpl &&) = delete;
+    InterruptCallbackImpl(const InterruptCallbackImpl &) = delete;
+    InterruptCallbackImpl & operator=(InterruptCallbackImpl &&) = delete;
+    InterruptCallbackImpl & operator=(const InterruptCallbackImpl &) = delete;
+
     ~InterruptCallbackImpl() override
     {
         auto interruptCallbacks(_interruptCallbacks.lock());
@@ -153,11 +163,7 @@ std::unique_ptr<InterruptCallback> createInterruptCallback(std::function<void()>
     auto interruptCallbacks(_interruptCallbacks.lock());
     auto token = interruptCallbacks->nextToken++;
     interruptCallbacks->callbacks.emplace(token, callback);
-
+    return std::make_unique<InterruptCallbackImpl>(token);
-    std::unique_ptr<InterruptCallbackImpl> res{new InterruptCallbackImpl{}};
-    res->token = token;
-
-    return std::unique_ptr<InterruptCallback>(res.release());
 }
 
 } // namespace nix