Add GrGpuResource::CacheAccess
Internal only helper class for manipulating and accessing cache keys.
BUG=skia:2889
Review URL: https://codereview.chromium.org/703303003
diff --git a/src/gpu/GrGpuResourceCacheAccess.h b/src/gpu/GrGpuResourceCacheAccess.h
new file mode 100644
index 0000000..af5c054
--- /dev/null
+++ b/src/gpu/GrGpuResourceCacheAccess.h
@@ -0,0 +1,96 @@
+
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrGpuResourceCacheAccess_DEFINED
+#define GrGpuResourceCacheAccess_DEFINED
+
+#include "GrGpuResource.h"
+
+/**
+ * This class allows code internal to Skia privileged access to manage the cache keys of a
+ * GrGpuResource object.
+ */
+class GrGpuResource::CacheAccess {
+public:
+ /**
+ * Sets a content key for the resource. If the resource was previously cached as scratch it will
+ * be converted to a content resource. Currently this may only be called once per resource. It
+ * fails if there is already a resource with the same content key. TODO: make this supplant the
+ * resource that currently is using the content key, allow resources' content keys to change,
+ * and allow removal of a content key to convert a resource back to scratch.
+ */
+ bool setContentKey(const GrResourceKey& contentKey) {
+ return fResource->setContentKey(contentKey);
+ }
+
+ /**
+ * Used by legacy cache to attach a cache entry. This is to be removed soon.
+ */
+ void setCacheEntry(GrResourceCacheEntry* cacheEntry) {
+ // GrResourceCache never changes the cacheEntry once one has been added.
+ SkASSERT(NULL == cacheEntry || NULL == fResource->fCacheEntry);
+ fResource->fCacheEntry = cacheEntry;
+ }
+
+ /**
+ * Is the resource in the legacy cache? This is to be removed soon.
+ */
+ bool isInCache() const { return SkToBool(fResource->fCacheEntry); }
+
+ /**
+ * Returns the cache entry for the legacy cache. This is to be removed soon.
+ */
+ GrResourceCacheEntry* getCacheEntry() const { return fResource->fCacheEntry; }
+
+ /**
+ * Is the resource currently cached as scratch? This means it has a valid scratch key and does
+ * not have a content key.
+ */
+ bool isScratch() const {
+ SkASSERT(fResource->fScratchKey.isScratch());
+ return NULL == this->getContentKey() && !fResource->fScratchKey.isNullScratch();
+ }
+
+ /**
+ * If this resource can be used as a scratch resource this returns a valid scratch key.
+ * Otherwise it returns a key for which isNullScratch is true. The resource may currently be
+ * used as content resource rather than scratch. Check isScratch().
+ */
+ const GrResourceKey& getScratchKey() const { return fResource->fScratchKey; }
+
+ /**
+ * If the resource is currently cached by a content key, the key is returned, otherwise NULL.
+ */
+ const GrResourceKey* getContentKey() const {
+ if (fResource->fContentKeySet) {
+ return &fResource->fContentKey;
+ }
+ return NULL;
+ }
+
+private:
+ CacheAccess(GrGpuResource* resource) : fResource(resource) { }
+ CacheAccess(const CacheAccess& that) : fResource(that.fResource) { }
+ CacheAccess& operator=(const CacheAccess&); // unimpl
+
+ // No taking addresses of this type.
+ const CacheAccess* operator&() const;
+ CacheAccess* operator&();
+
+ GrGpuResource* fResource;
+
+ friend class GrGpuResource; // to construct/copy this type.
+};
+
+inline GrGpuResource::CacheAccess GrGpuResource::cacheAccess() { return CacheAccess(this); }
+
+inline const GrGpuResource::CacheAccess GrGpuResource::cacheAccess() const {
+ return CacheAccess(const_cast<GrGpuResource*>(this));
+}
+
+#endif