Track readable names of vmethod hooks for diagnostic messages.

Note that this changes the ABI of all plugins that use hooks.

library/VTableInterpose.cpp

@@ -288,9 +288,9 @@ void VMethodInterposeLinkBase::set_chain(void *chain)
     addr_to_method_pointer_(chain_mptr, chain);
 }
 
-VMethodInterposeLinkBase::VMethodInterposeLinkBase(virtual_identity *host, int vmethod_idx, void *interpose_method, void *chain_mptr, int priority)
+VMethodInterposeLinkBase::VMethodInterposeLinkBase(virtual_identity *host, int vmethod_idx, void *interpose_method, void *chain_mptr, int priority, const char *name)
     : host(host), vmethod_idx(vmethod_idx), interpose_method(interpose_method),
-      chain_mptr(chain_mptr), priority(priority),
+      chain_mptr(chain_mptr), priority(priority), name_str(name),
       applied(false), saved_chain(NULL), next(NULL), prev(NULL)
 {
     if (vmethod_idx < 0 || interpose_method == NULL)
@@ -303,8 +303,8 @@ VMethodInterposeLinkBase::VMethodInterposeLinkBase(virtual_identity *host, int v
          * - interpose_method comes from method_pointer_to_addr_
          */
 
-        fprintf(stderr, "Bad VMethodInterposeLinkBase arguments: %d %08x\n",
-                vmethod_idx, unsigned(interpose_method));
+        fprintf(stderr, "Bad VMethodInterposeLinkBase arguments: %d %08x (%s)\n",
+                vmethod_idx, unsigned(interpose_method), name_str);
         fflush(stderr);
         abort();
     }

library/include/VTableInterpose.h

@@ -141,7 +141,7 @@ namespace DFHack
 
 #define IMPLEMENT_VMETHOD_INTERPOSE_PRIO(class,name,priority) \
     DFHack::VMethodInterposeLink<class::interpose_base,class::interpose_ptr_##name> \
-        class::interpose_##name(&class::interpose_base::name, &class::interpose_fn_##name, priority);
+        class::interpose_##name(&class::interpose_base::name, &class::interpose_fn_##name, priority, #class"::"#name);
 
 #define IMPLEMENT_VMETHOD_INTERPOSE(class,name) IMPLEMENT_VMETHOD_INTERPOSE_PRIO(class,name,0)
 
@@ -161,6 +161,7 @@ namespace DFHack
         void *interpose_method; // Pointer to the code of the interposing method
         void *chain_mptr;       // Pointer to the chain field in the subclass below
         int priority;           // Higher priority hooks are called earlier
+        const char *name_str;   // Name of the hook
 
         bool applied;           // True if this hook is currently applied
         void *saved_chain;      // Pointer to the code of the original vmethod or next hook
@@ -179,12 +180,14 @@ namespace DFHack
         VMethodInterposeLinkBase *get_first_interpose(virtual_identity *id);
         bool find_child_hosts(virtual_identity *cur, void *vmptr);
     public:
-        VMethodInterposeLinkBase(virtual_identity *host, int vmethod_idx, void *interpose_method, void *chain_mptr, int priority);
+        VMethodInterposeLinkBase(virtual_identity *host, int vmethod_idx, void *interpose_method, void *chain_mptr, int priority, const char *name);
         ~VMethodInterposeLinkBase();
 
         bool is_applied() { return applied; }
         bool apply(bool enable = true);
         void remove();
+
+        const char *name() { return name_str; }
     };
 
     template<class Base, class Ptr>
@@ -198,13 +201,13 @@ namespace DFHack
         operator Ptr () { return chain; }
 
         template<class Ptr2>
-        VMethodInterposeLink(Ptr target, Ptr2 src, int priority)
+        VMethodInterposeLink(Ptr target, Ptr2 src, int priority, const char *name)
             : VMethodInterposeLinkBase(
                 &Base::_identity,
                 vmethod_pointer_to_idx(target),
                 method_pointer_to_addr(src),
                 &chain,
-                priority
+                priority, name
               )
         { src = target; /* check compatibility */ }
     };

plugins/tweak.cpp

@@ -937,14 +937,14 @@ static void enable_hook(color_ostream &out, VMethodInterposeLinkBase &hook, vect
     if (vector_get(parameters, 1) == "disable")
     {
         hook.remove();
-        out.print("Disabled tweak %s\n", parameters[0].c_str());
+        out.print("Disabled tweak %s (%s)\n", parameters[0].c_str(), hook.name());
     }
     else
     {
         if (hook.apply())
-            out.print("Enabled tweak %s\n", parameters[0].c_str());
+            out.print("Enabled tweak %s (%s)\n", parameters[0].c_str(), hook.name());
         else
-            out.printerr("Could not activate tweak %s\n", parameters[0].c_str());
+            out.printerr("Could not activate tweak %s (%s)\n", parameters[0].c_str(), hook.name());
     }
 }