gfx/skia/trunk/src/gpu/GrBinHashKey.h

Sat, 03 Jan 2015 20:18:00 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Sat, 03 Jan 2015 20:18:00 +0100
branch
TOR_BUG_3246
changeset 7
129ffea94266
permissions
-rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

michael@0 1
michael@0 2 /*
michael@0 3 * Copyright 2011 Google Inc.
michael@0 4 *
michael@0 5 * Use of this source code is governed by a BSD-style license that can be
michael@0 6 * found in the LICENSE file.
michael@0 7 */
michael@0 8
michael@0 9
michael@0 10 #ifndef GrBinHashKey_DEFINED
michael@0 11 #define GrBinHashKey_DEFINED
michael@0 12
michael@0 13 #include "GrTypes.h"
michael@0 14
michael@0 15 /**
michael@0 16 * GrBinHashKey is a hash key class that can take a data chunk of any predetermined
michael@0 17 * length. The hash function used is the One-at-a-Time Hash
michael@0 18 * (http://burtleburtle.net/bob/hash/doobs.html).
michael@0 19 */
michael@0 20 template<size_t KEY_SIZE>
michael@0 21 class GrBinHashKey {
michael@0 22 public:
michael@0 23 enum { kKeySize = KEY_SIZE };
michael@0 24
michael@0 25 GrBinHashKey() {
michael@0 26 this->reset();
michael@0 27 }
michael@0 28
michael@0 29 void reset() {
michael@0 30 fHash = 0;
michael@0 31 #ifdef SK_DEBUG
michael@0 32 fIsValid = false;
michael@0 33 #endif
michael@0 34 }
michael@0 35
michael@0 36 void setKeyData(const uint32_t* SK_RESTRICT data) {
michael@0 37 SK_COMPILE_ASSERT(KEY_SIZE % 4 == 0, key_size_mismatch);
michael@0 38 memcpy(&fData, data, KEY_SIZE);
michael@0 39
michael@0 40 uint32_t hash = 0;
michael@0 41 size_t len = KEY_SIZE;
michael@0 42 while (len >= 4) {
michael@0 43 hash += *data++;
michael@0 44 hash += (hash << 10);
michael@0 45 hash ^= (hash >> 6);
michael@0 46 len -= 4;
michael@0 47 }
michael@0 48 hash += (hash << 3);
michael@0 49 hash ^= (hash >> 11);
michael@0 50 hash += (hash << 15);
michael@0 51 #ifdef SK_DEBUG
michael@0 52 fIsValid = true;
michael@0 53 #endif
michael@0 54 fHash = hash;
michael@0 55 }
michael@0 56
michael@0 57 bool operator==(const GrBinHashKey<KEY_SIZE>& key) const {
michael@0 58 SkASSERT(fIsValid && key.fIsValid);
michael@0 59 if (fHash != key.fHash) {
michael@0 60 return false;
michael@0 61 }
michael@0 62 for (size_t i = 0; i < SK_ARRAY_COUNT(fData); ++i) {
michael@0 63 if (fData[i] != key.fData[i]) {
michael@0 64 return false;
michael@0 65 }
michael@0 66 }
michael@0 67 return true;
michael@0 68 }
michael@0 69
michael@0 70 bool operator<(const GrBinHashKey<KEY_SIZE>& key) const {
michael@0 71 SkASSERT(fIsValid && key.fIsValid);
michael@0 72 for (size_t i = 0; i < SK_ARRAY_COUNT(fData); ++i) {
michael@0 73 if (fData[i] < key.fData[i]) {
michael@0 74 return true;
michael@0 75 } else if (fData[i] > key.fData[i]) {
michael@0 76 return false;
michael@0 77 }
michael@0 78 }
michael@0 79 return false;
michael@0 80 }
michael@0 81
michael@0 82 uint32_t getHash() const {
michael@0 83 SkASSERT(fIsValid);
michael@0 84 return fHash;
michael@0 85 }
michael@0 86
michael@0 87 const uint8_t* getData() const {
michael@0 88 SkASSERT(fIsValid);
michael@0 89 return reinterpret_cast<const uint8_t*>(fData);
michael@0 90 }
michael@0 91
michael@0 92 private:
michael@0 93 uint32_t fHash;
michael@0 94 uint32_t fData[KEY_SIZE / sizeof(uint32_t)]; // Buffer for key storage.
michael@0 95
michael@0 96 #ifdef SK_DEBUG
michael@0 97 public:
michael@0 98 bool fIsValid;
michael@0 99 #endif
michael@0 100 };
michael@0 101
michael@0 102 #endif

mercurial