1 /* 2 * Copyright 2016 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkUrlDataManager_DEFINED 9 #define SkUrlDataManager_DEFINED 10 11 #include "SkChecksum.h" 12 #include "SkData.h" 13 #include "SkString.h" 14 #include "SkTDynamicHash.h" 15 16 /* 17 * A simple class which allows clients to add opaque data types, and returns a url where this data 18 * will be hosted. Its up to the owner of this class to actually serve the data. 19 */ 20 bool operator==(const SkData& a, const SkData& b); 21 22 class UrlDataManager { 23 public: 24 UrlDataManager(SkString rootUrl); ~UrlDataManager()25 ~UrlDataManager() { this->reset(); } 26 27 /* 28 * Adds a data blob to the cache with a particular content type. UrlDataManager will hash 29 * the blob data to ensure uniqueness 30 */ 31 SkString addData(SkData*, const char* contentType); 32 33 struct UrlData : public SkRefCnt { 34 SkString fUrl; 35 SkString fContentType; 36 SkAutoTUnref<SkData> fData; 37 }; 38 39 /* 40 * returns the UrlData object which should be hosted at 'url' 41 */ getDataFromUrl(SkString url)42 UrlData* getDataFromUrl(SkString url) { 43 return fUrlLookup.find(url); 44 } 45 void reset(); 46 47 private: 48 struct LookupTrait { 49 // We use the data as a hash, this is not really optimal but is fine until proven otherwise GetKeyLookupTrait50 static const SkData& GetKey(const UrlData& data) { 51 return *data.fData.get(); 52 } 53 HashLookupTrait54 static uint32_t Hash(const SkData& key) { 55 return SkChecksum::Murmur3(key.bytes(), key.size()); 56 } 57 }; 58 59 struct ReverseLookupTrait { GetKeyReverseLookupTrait60 static const SkString& GetKey(const UrlData& data) { 61 return data.fUrl; 62 } 63 HashReverseLookupTrait64 static uint32_t Hash(const SkString& key) { 65 return SkChecksum::Murmur3(key.c_str(), strlen(key.c_str())); 66 } 67 }; 68 69 70 SkString fRootUrl; 71 SkTDynamicHash<UrlData, SkData, LookupTrait> fCache; 72 SkTDynamicHash<UrlData, SkString, ReverseLookupTrait> fUrlLookup; 73 uint32_t fDataId; 74 }; 75 76 #endif 77