Implement cvar callback functionality

With these, cvars can run arbitrary functions to bounds-check themselves or
perform some other task such as cleanup. Use the function Cvar_RegisterCallback.

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@12629 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/cvar.c b/cvar.c
index affdc5565d8ac716e48222bc79e429ed4283d510..be6ed386f08405660bdf053b7884830703a965fe 100644 (file)
--- a/cvar.c
+++ b/cvar.c
@@ -349,21 +349,28 @@ static void Cvar_SetQuick_Internal (cvar_t *var, const char *value)
        qboolean changed;
        size_t valuelen;
        char vabuf[1024];
+       char new_value[MAX_INPUTLINE];
 
        changed = strcmp(var->string, value) != 0;
        // LadyHavoc: don't reallocate when there is no change
        if (!changed)
                return;
 
+       memcpy(new_value,value,MAX_INPUTLINE);
+       
+       // Call the function stored in the cvar for bounds checking, cleanup, etc
+       if (var->callback)
+               var->callback(new_value);
+
        // LadyHavoc: don't reallocate when the buffer is the same size
-       valuelen = strlen(value);
+       valuelen = strlen(new_value);
        if (!var->string || strlen(var->string) != valuelen)
        {
                Z_Free ((char *)var->string);   // free the old value string
 
                var->string = (char *)Z_Malloc (valuelen + 1);
        }
-       memcpy ((char *)var->string, value, valuelen + 1);
+       memcpy ((char *)var->string, new_value, valuelen + 1);
        var->value = atof (var->string);
        var->integer = (int) var->value;
        if ((var->flags & CVAR_NOTIFY) && changed && sv.active && !sv_disablenotify.integer)
@@ -482,6 +489,11 @@ void Cvar_SetValue(cvar_state_t *cvars, const char *var_name, float value)
        Cvar_Set(cvars, var_name, val);
 }
 
+void Cvar_RegisterCallback(cvar_t *variable, void (*callback)(char *))
+{
+       variable->callback = callback;
+}
+
 /*
 ============
 Cvar_RegisterVariable

diff --git a/cvar.h b/cvar.h
index 4838824c39b709ebe7ee8de3cc6d7b7fb7e8a3cd..2bbcd1dc177bc9a4470d30ff59064ca7127db208 100644 (file)
--- a/cvar.h
+++ b/cvar.h
@@ -131,6 +131,8 @@ typedef struct cvar_s
 
        const char *defstring;
 
+       void (*callback)(char *value);
+
        // values at init (for Cvar_RestoreInitState)
        qboolean initstate; // indicates this existed at init
        int initflags;
@@ -170,6 +172,8 @@ void Cvar_MenuOption(cvar_t *variable, int menu, int value[16], const char *name
 
 /// registers a cvar that already has the name, string, and optionally the
 /// archive elements set.
+void Cvar_RegisterCallback(cvar_t *variable, void (*callback)(char *));
+
 void Cvar_RegisterVariable(cvar_t *variable);
 
 /// equivelant to "<name> <variable>" typed at the console