simplified Resource interface, return empty resource if not found, pass by value

Author: Martin Klang

LibSource/Resource.cpp

@@ -4,7 +4,6 @@
 #include "OpenWareMidiControl.h"
 #include "ServiceCall.h"
 #include "ProgramVector.h"
-#include "FloatArray.h"
 
 template<typename Array, typename Element>
 Array Resource::asArray(size_t offset, size_t max_size) {
@@ -16,43 +15,41 @@ Array Resource::asArray(size_t offset, size_t max_size) {
 
 template FloatArray Resource::asArray<FloatArray, float>(size_t offset, size_t max_size);
 
-void Resource::destroy(Resource* resource) {
-  if (resource && resource->allocated)
-    delete[] (uint8_t*)resource->data;
-  delete resource;
+Resource::~Resource() {
+  if(allocated)
+    delete[] (uint8_t*)data;
 }
 
-Resource* Resource::open(const char* name){
+Resource Resource::open(const char* name){
   uint8_t* data = NULL;
   size_t offset = 0;
   size_t size = 0;
   void* args[] = {
 		  (void*)name, (void*)&data, (void*)&offset, (void*)&size
   };
   if(getProgramVector()->serviceCall(OWL_SERVICE_LOAD_RESOURCE, args, 4) == OWL_SERVICE_OK)
-    return new Resource(name, size, data);
-  return NULL;
+    return Resource(name, size, data);
+  return Resource();
 }
 
-Resource* Resource::load(const char* name){
-  Resource* resource = Resource::open(name);
-  if(resource != NULL && resource->data == NULL){
-    uint8_t* data = new uint8_t[resource->size];
+Resource Resource::load(const char* name){
+  Resource resource = Resource::open(name);
+  if(resource.exists() && !resource.hasData()){
+    uint8_t* data = new uint8_t[resource.size];
     size_t offset = 0;
     void* args[] = {
-		    (void*)name, (void*)&data, (void*)&offset, (void*)&resource->size
+		    (void*)name, (void*)&data, (void*)&offset, (void*)&resource.size
     };
     if (getProgramVector()->serviceCall(OWL_SERVICE_LOAD_RESOURCE, args, 4) == OWL_SERVICE_OK){
-      resource->data = data;
-      resource->allocated = true;
+      resource.data = data;
+      resource.allocated = true;
     }else{
       delete[] data;
     }
   }
   return resource;
 }
 
-
 size_t Resource::read(void* dest, size_t len, size_t offset){
   if(this->data == NULL){
     void* args[] = {

LibSource/Resource.h

@@ -2,6 +2,7 @@
 #define __RESOURCE_STORAGE_H__
 
 #include <cstddef>
+#include "FloatArray.h"
 
 class Resource {
 public:
@@ -26,6 +27,10 @@ class Resource {
     return size;
   }    
 
+  bool exists() const {
+    return size != 0;
+  }
+
   /**
    * Get resource name
    */
@@ -42,28 +47,26 @@ class Resource {
   template<typename Array, typename Element>
   Array asArray(size_t offset = 0, size_t max_size = 0xFFFFFFFF);
 
+  FloatArray asFloatArray(size_t offset = 0, size_t max_size = 0xFFFFFFFF){
+    return asArray<FloatArray, float>(offset, max_size);
+  }
+  
   /**
-   * Get resource from storage. Creates a new Resource on the heap.
-   * Should be garbage collected with Resource::destroy()
+   * Get resource from storage.
    * 
    * @param name resource name
    * 
    * @return NULL if resource does not exist or can't be read.
    * 
    */
-  static Resource* open(const char* name);
-
-  /**
-   * Open resource and load data. Creates a new Resource on the heap and 
-   * allocates extra memory if required.
-   * Must be garbage collected with Resource::destroy()
-   */
-  static Resource* load(const char* name);
+  static Resource open(const char* name);
 
   /**
-   * Destroy allocated memory used by a resource
+   * Open resource and load data.
+   * Allocates extra memory if required, which will be garbage collected 
+   * in the object destructor.
    */
-  static void destroy(Resource* resource);
+  static Resource load(const char* name);
 
   /**
    * Read data from resource into memory
@@ -75,12 +78,14 @@ class Resource {
    */
   size_t read(void* dest, size_t len, size_t offset=0); 
 
+  Resource(): name(NULL), size(0), data(NULL), allocated(false) {}
+  ~Resource();
 protected:
   Resource(const char* name, size_t size, void* data)
     : name(name), size(size), data(data) {}
-  const char* name = NULL;
-  size_t size = 0;
-  void* data = NULL;
-  bool allocated = false;
+  const char* name;
+  size_t size;
+  void* data;
+  bool allocated;
 };
 #endif