ncd: NCDInterpreter, NCDModule: convert non-ContinuousString strings in statement arguments to ContinuousString, and implement a module flag to

suppress this conversion

ncd/NCDInterpreter.c

@@ -900,6 +900,14 @@ void process_advance (struct process *p)
         goto fail1;
     }
     
+    // convert non-continuous strings unless the module can handle them
+    if (!(module->module.flags & NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS)) {
+        if (!NCDValMem_ConvertNonContinuousStrings(&ps->args_mem, &args)) {
+            STATEMENT_LOG(ps, BLOG_ERROR, "NCDValMem_ConvertNonContinuousStrings failed");
+            goto fail1;
+        }
+    }
+    
     // allocate memory
     if (!statement_allocate_memory(ps, module->module.alloc_size)) {
         STATEMENT_LOG(ps, BLOG_ERROR, "failed to allocate memory");

ncd/NCDModule.h

@@ -247,7 +247,9 @@ struct NCDModuleInst_new_params {
     /**
      * A reference to the argument list for the module instance.
      * The reference remains valid as long as the backend instance
-     * exists.
+     * exists. Unless the module has the NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS
+     * flag set, it is guaranteed that any strings within the arguments will be
+     * some kind of ContinuousString.
      */
     NCDValRef args;
     
@@ -404,7 +406,10 @@ typedef struct NCDModuleProcess_s {
  *                       The caller must ensure that the NCDObject that was used is of the type
  *                       expected by the module being instanciated.
  * @param args arguments to the module. Must be a list value. Must be available and unchanged
- *             as long as the instance exists.
+ *             as long as the instance exists. Unless the module has the
+ *             NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS flag set, any strings within the
+ *             arguments must be some kind of ContinuousString. This can be ensured by calling
+ *             {@link NCDValMem_ConvertNonContinuousStrings}.
  * @param user argument to callback functions
  * @param params more parameters, see {@link NCDModuleInst_params}
  */
@@ -813,6 +818,7 @@ typedef int (*NCDModule_func_getobj) (void *o, NCD_string_id_t name, NCDObject *
 typedef void (*NCDModule_func_clean) (void *o);
 
 #define NCDMODULE_FLAG_CAN_RESOLVE_WHEN_DOWN (1 << 0)
+#define NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS (1 << 1)
 
 /**
  * Structure encapsulating the implementation of a module backend.
@@ -874,6 +880,12 @@ struct NCDModule {
      *   Whether the interpreter is allowed to call func_getvar and func_getobj
      *   even when the backend instance is in down state (as opposed to just
      *   in up state.
+     * 
+     * - NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS
+     *   If not set, strings within arguments which are not some kind of ContinuousString
+     *   will be converted to some kind of ContinuousString before the module's init
+     *   function is called. If set, they will not be, and the module must work with any
+     *   kind of strings (i.e. {@link NCDVal_StringData} may not be allowed).
      */
     int flags;