Allow code to be passed in error handler.

Not used yet, but we can use it to throw different exception types.

src/core/PlumedMain.h

@@ -102,7 +102,7 @@ private:
 /// Should only be called from \ref plumed_plumedmain_cmd().
   typedef struct {
     void* ptr;
-    void(*handler)(void* ptr,const char*);
+    void(*handler)(void* ptr,int code,const char*);
   } plumed_error_handler;
 
   plumed_error_handler error_handler= {NULL,NULL};
@@ -392,7 +392,7 @@ public:
 /// Call error handler.
 /// Should only be called from \ref plumed_plumedmain_cmd().
 /// If the error handler was not set, returns false.
-  bool callErrorHandler(const char* msg)const;
+  bool callErrorHandler(int code,const char* msg)const;
 };
 
 /////
@@ -464,9 +464,9 @@ void PlumedMain::setEndPlumed() {
 }
 
 inline
-bool PlumedMain::callErrorHandler(const char* msg)const {
+bool PlumedMain::callErrorHandler(int code,const char* msg)const {
   if(error_handler.handler) {
-    error_handler.handler(error_handler.ptr,msg);
+    error_handler.handler(error_handler.ptr,code,msg);
     return true;
   } else return false;
 }

src/core/PlumedMainInitializer.cpp

@@ -44,7 +44,7 @@ extern "C" void plumed_plumedmain_cmd(void*plumed,const char*key,const void*val)
 // if a error_handler was provided, we use it to manage this exception.
 // this allows an exception to be catched also if the MD code
 // was linked against a different C++ library
-    if(!p->callErrorHandler(e.what())) throw;
+    if(!p->callErrorHandler(2,e.what())) throw;
   }
 }
 

src/wrapper/Plumed.h

@@ -521,7 +521,7 @@ typedef struct {
 
 typedef struct {
   void* ptr;
-  void(*handler)(void* ptr,const char*);
+  void(*handler)(void* ptr,int code,const char*);
 } plumed_error_handler;
 
 /** \relates plumed
@@ -958,8 +958,9 @@ class Plumed {
   /**
     Error handler installed to rethrow exceptions.
   */
-  static void cxx_error_handler(void*ptr, const char*what) {
+  static void cxx_error_handler(void*ptr, int code, const char*what) {
     (void) ptr;
+    (void) code;
     throw Plumed::Exception(what);
   }
 
@@ -2094,9 +2095,9 @@ void plumed_cmd(plumed p,const char*key,const void*val) {
   if(!pimpl->p) {
     if(pimpl->error_handler.handler) {
       if(pimpl->used_plumed_kernel) {
-        pimpl->error_handler.handler(pimpl->error_handler.ptr,"You are trying to use plumed, but it is not available.\nCheck your PLUMED_KERNEL environment variable.");
+        pimpl->error_handler.handler(pimpl->error_handler.ptr,1,"You are trying to use plumed, but it is not available.\nCheck your PLUMED_KERNEL environment variable.");
       } else {
-        pimpl->error_handler.handler(pimpl->error_handler.ptr,"You are trying to use plumed, but it is not available.");
+        pimpl->error_handler.handler(pimpl->error_handler.ptr,1,"You are trying to use plumed, but it is not available.");
       }
     } else {
       __PLUMED_FPRINTF(stderr,"+++ ERROR: You are trying to use plumed, but it is not available. +++\n");