client Operation expose PV name

Desirable to include in error messages if nothing else

src/client.cpp

@@ -165,6 +165,11 @@ OperationBase::OperationBase(operation_t op, const std::shared_ptr<Channel>& cha
 
 OperationBase::~OperationBase() {}
 
+const std::string& OperationBase::name()
+{
+    return chan->name;
+}
+
 Value OperationBase::wait(double timeout)
 {
     if(!waiter)

src/clientimpl.h

@@ -54,6 +54,7 @@ struct OperationBase : public Operation
     virtual void createOp() =0;
     virtual void disconnected(const std::shared_ptr<OperationBase>& self) =0;
 
+    virtual const std::string& name() override final;
     virtual Value wait(double timeout=-1.0) override final;
     virtual void interrupt() override final;
 };

src/pvxs/client.h

@@ -98,6 +98,7 @@ public:
 
 //! Handle for in-progress operation
 struct PVXS_API Operation {
+    //! Operation type
     const enum operation_t {
         Info    = 17, // CMD_GET_FIELD
         Get     = 10, // CMD_GET
@@ -111,6 +112,9 @@ struct PVXS_API Operation {
     Operation& operator=(const Operation&) = delete;
     virtual ~Operation() =0;
 
+    //! PV name
+    virtual const std::string& name() =0;
+
     //! Explicitly cancel a pending operation.
     //! Blocks until an in-progress callback has completed.
     virtual void cancel() =0;