bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2012 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 | |
bsalomon@google.com | 4c2443e | 2012-12-06 20:58:57 +0000 | [diff] [blame] | 8 | #ifndef SkTLList_DEFINED |
| 9 | #define SkTLList_DEFINED |
| 10 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 11 | #include "SkTInternalLList.h" |
| 12 | #include "SkTemplates.h" |
| 13 | |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 14 | template <typename T> class SkTLList; |
| 15 | template <typename T> |
| 16 | inline void* operator new(size_t, SkTLList<T>* list, |
| 17 | typename SkTLList<T>::Placement placement, |
| 18 | const typename SkTLList<T>::Iter& location); |
| 19 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 20 | /** Doubly-linked list of objects. The objects' lifetimes are controlled by the list. I.e. the |
| 21 | the list creates the objects and they are deleted upon removal. This class block-allocates |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 22 | space for entries based on a param passed to the constructor. |
| 23 | |
| 24 | Elements of the list can be constructed in place using the following macros: |
| 25 | SkNEW_INSERT_IN_LLIST_BEFORE(list, location, type_name, args) |
| 26 | SkNEW_INSERT_IN_LLIST_AFTER(list, location, type_name, args) |
| 27 | where list is a SkTLList<type_name>*, location is an iterator, and args is the paren-surrounded |
| 28 | constructor arguments for type_name. These macros behave like addBefore() and addAfter(). |
| 29 | */ |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 30 | template <typename T> |
| 31 | class SkTLList : public SkNoncopyable { |
| 32 | private: |
| 33 | struct Block; |
| 34 | struct Node { |
| 35 | char fObj[sizeof(T)]; |
| 36 | SK_DECLARE_INTERNAL_LLIST_INTERFACE(Node); |
| 37 | Block* fBlock; // owning block. |
| 38 | }; |
| 39 | typedef SkTInternalLList<Node> NodeList; |
| 40 | |
| 41 | public: |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 42 | |
| 43 | class Iter; |
| 44 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 45 | /** allocCnt is the number of objects to allocate as a group. In the worst case fragmentation |
| 46 | each object is using the space required for allocCnt unfragmented objects. */ |
| 47 | SkTLList(int allocCnt = 1) : fCount(0), fAllocCnt(allocCnt) { |
| 48 | SkASSERT(allocCnt > 0); |
| 49 | this->validate(); |
| 50 | } |
| 51 | |
| 52 | ~SkTLList() { |
| 53 | this->validate(); |
| 54 | typename NodeList::Iter iter; |
| 55 | Node* node = iter.init(fList, Iter::kHead_IterStart); |
| 56 | while (NULL != node) { |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 57 | SkTCast<T*>(node->fObj)->~T(); |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 58 | Block* block = node->fBlock; |
| 59 | node = iter.next(); |
| 60 | if (0 == --block->fNodesInUse) { |
| 61 | for (int i = 0; i < fAllocCnt; ++i) { |
| 62 | block->fNodes[i].~Node(); |
| 63 | } |
| 64 | sk_free(block); |
| 65 | } |
| 66 | } |
| 67 | } |
skia.committer@gmail.com | e659c2e | 2012-12-04 02:01:25 +0000 | [diff] [blame] | 68 | |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 69 | T* addToHead(const T& t) { |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 70 | this->validate(); |
| 71 | Node* node = this->createNode(); |
| 72 | fList.addToHead(node); |
| 73 | SkNEW_PLACEMENT_ARGS(node->fObj, T, (t)); |
| 74 | this->validate(); |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 75 | return reinterpret_cast<T*>(node->fObj); |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 76 | } |
| 77 | |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 78 | T* addToTail(const T& t) { |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 79 | this->validate(); |
| 80 | Node* node = this->createNode(); |
| 81 | fList.addToTail(node); |
| 82 | SkNEW_PLACEMENT_ARGS(node->fObj, T, (t)); |
| 83 | this->validate(); |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 84 | return reinterpret_cast<T*>(node->fObj); |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 85 | } |
| 86 | |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 87 | /** Adds a new element to the list before the location indicated by the iterator. If the |
| 88 | iterator refers to a NULL location then the new element is added at the tail */ |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 89 | T* addBefore(const T& t, const Iter& location) { |
| 90 | return SkNEW_PLACEMENT_ARGS(this->internalAddBefore(location), T, (t)); |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | /** Adds a new element to the list after the location indicated by the iterator. If the |
| 94 | iterator refers to a NULL location then the new element is added at the head */ |
bsalomon@google.com | c6b3e48 | 2012-12-07 20:43:52 +0000 | [diff] [blame] | 95 | T* addAfter(const T& t, const Iter& location) { |
| 96 | return SkNEW_PLACEMENT_ARGS(this->internalAddAfter(location), T, (t)); |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 97 | } |
| 98 | |
| 99 | /** Convenience methods for getting an iterator initialized to the head/tail of the list. */ |
| 100 | Iter headIter() const { return Iter(*this, Iter::kHead_IterStart); } |
| 101 | Iter tailIter() const { return Iter(*this, Iter::kTail_IterStart); } |
| 102 | |
bsalomon@google.com | 4c2443e | 2012-12-06 20:58:57 +0000 | [diff] [blame] | 103 | T* head() { return Iter(*this, Iter::kHead_IterStart).get(); } |
| 104 | T* tail() { return Iter(*this, Iter::kTail_IterStart).get(); } |
| 105 | const T* head() const { return Iter(*this, Iter::kHead_IterStart).get(); } |
| 106 | const T* tail() const { return Iter(*this, Iter::kTail_IterStart).get(); } |
| 107 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 108 | void popHead() { |
| 109 | this->validate(); |
| 110 | Node* node = fList.head(); |
| 111 | if (NULL != node) { |
| 112 | this->removeNode(node); |
| 113 | } |
| 114 | this->validate(); |
| 115 | } |
| 116 | |
| 117 | void popTail() { |
| 118 | this->validate(); |
| 119 | Node* node = fList.head(); |
| 120 | if (NULL != node) { |
| 121 | this->removeNode(node); |
| 122 | } |
| 123 | this->validate(); |
| 124 | } |
| 125 | |
| 126 | void remove(T* t) { |
| 127 | this->validate(); |
| 128 | Node* node = reinterpret_cast<Node*>(t); |
| 129 | SkASSERT(reinterpret_cast<T*>(node->fObj) == t); |
| 130 | this->removeNode(node); |
| 131 | this->validate(); |
| 132 | } |
| 133 | |
| 134 | void reset() { |
| 135 | this->validate(); |
| 136 | Iter iter(*this, Iter::kHead_IterStart); |
| 137 | while (iter.get()) { |
| 138 | Iter next = iter; |
| 139 | next.next(); |
| 140 | this->remove(iter.get()); |
| 141 | iter = next; |
| 142 | } |
| 143 | SkASSERT(0 == fCount); |
| 144 | this->validate(); |
| 145 | } |
| 146 | |
| 147 | int count() const { return fCount; } |
| 148 | bool isEmpty() const { this->validate(); return 0 == fCount; } |
| 149 | |
| 150 | bool operator== (const SkTLList& list) const { |
| 151 | if (this == &list) { |
| 152 | return true; |
| 153 | } |
| 154 | if (fCount != list.fCount) { |
| 155 | return false; |
| 156 | } |
| 157 | for (Iter a(*this, Iter::kHead_IterStart), b(list, Iter::kHead_IterStart); |
| 158 | a.get(); |
| 159 | a.next(), b.next()) { |
| 160 | SkASSERT(NULL != b.get()); // already checked that counts match. |
| 161 | if (!(*a.get() == *b.get())) { |
| 162 | return false; |
| 163 | } |
| 164 | } |
| 165 | return true; |
| 166 | } |
| 167 | bool operator!= (const SkTLList& list) const { return !(*this == list); } |
| 168 | |
| 169 | /** The iterator becomes invalid if the element it refers to is removed from the list. */ |
| 170 | class Iter : private NodeList::Iter { |
| 171 | private: |
| 172 | typedef typename NodeList::Iter INHERITED; |
| 173 | |
| 174 | public: |
| 175 | typedef typename INHERITED::IterStart IterStart; |
| 176 | //!< Start the iterator at the head of the list. |
| 177 | static const IterStart kHead_IterStart = INHERITED::kHead_IterStart; |
| 178 | //!< Start the iterator at the tail of the list. |
| 179 | static const IterStart kTail_IterStart = INHERITED::kTail_IterStart; |
| 180 | |
| 181 | Iter() {} |
| 182 | |
| 183 | Iter(const SkTLList& list, IterStart start) { |
| 184 | INHERITED::init(list.fList, start); |
| 185 | } |
| 186 | |
| 187 | T* init(const SkTLList& list, IterStart start) { |
| 188 | return this->nodeToObj(INHERITED::init(list.fList, start)); |
| 189 | } |
| 190 | |
| 191 | T* get() { return this->nodeToObj(INHERITED::get()); } |
| 192 | |
| 193 | T* next() { return this->nodeToObj(INHERITED::next()); } |
| 194 | |
| 195 | T* prev() { return this->nodeToObj(INHERITED::prev()); } |
| 196 | |
| 197 | Iter& operator= (const Iter& iter) { INHERITED::operator=(iter); return *this; } |
| 198 | |
| 199 | private: |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 200 | friend class SkTLList; |
| 201 | Node* getNode() { return INHERITED::get(); } |
| 202 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 203 | T* nodeToObj(Node* node) { |
| 204 | if (NULL != node) { |
| 205 | return reinterpret_cast<T*>(node->fObj); |
| 206 | } else { |
| 207 | return NULL; |
| 208 | } |
| 209 | } |
| 210 | }; |
| 211 | |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 212 | // For use with operator new |
| 213 | enum Placement { |
| 214 | kBefore_Placement, |
| 215 | kAfter_Placement, |
| 216 | }; |
| 217 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 218 | private: |
| 219 | struct Block { |
| 220 | int fNodesInUse; |
| 221 | Node fNodes[1]; |
| 222 | }; |
| 223 | |
| 224 | size_t blockSize() const { return sizeof(Block) + sizeof(Node) * (fAllocCnt-1); } |
| 225 | |
| 226 | Node* createNode() { |
| 227 | Node* node = fFreeList.head(); |
| 228 | if (NULL != node) { |
| 229 | fFreeList.remove(node); |
| 230 | ++node->fBlock->fNodesInUse; |
| 231 | } else { |
| 232 | Block* block = reinterpret_cast<Block*>(sk_malloc_flags(this->blockSize(), 0)); |
| 233 | node = &block->fNodes[0]; |
| 234 | SkNEW_PLACEMENT(node, Node); |
| 235 | node->fBlock = block; |
| 236 | block->fNodesInUse = 1; |
| 237 | for (int i = 1; i < fAllocCnt; ++i) { |
| 238 | SkNEW_PLACEMENT(block->fNodes + i, Node); |
| 239 | fFreeList.addToHead(block->fNodes + i); |
| 240 | block->fNodes[i].fBlock = block; |
| 241 | } |
| 242 | } |
| 243 | ++fCount; |
| 244 | return node; |
| 245 | } |
| 246 | |
| 247 | void removeNode(Node* node) { |
| 248 | SkASSERT(NULL != node); |
| 249 | fList.remove(node); |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 250 | SkTCast<T*>(node->fObj)->~T(); |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 251 | if (0 == --node->fBlock->fNodesInUse) { |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 252 | Block* block = node->fBlock; |
| 253 | for (int i = 0; i < fAllocCnt; ++i) { |
| 254 | if (block->fNodes + i != node) { |
| 255 | fFreeList.remove(block->fNodes + i); |
| 256 | } |
| 257 | block->fNodes[i].~Node(); |
| 258 | } |
| 259 | sk_free(block); |
| 260 | } else { |
| 261 | fFreeList.addToHead(node); |
| 262 | } |
| 263 | --fCount; |
| 264 | this->validate(); |
| 265 | } |
| 266 | |
| 267 | void validate() const { |
| 268 | #ifdef SK_DEBUG |
| 269 | SkASSERT((0 == fCount) == fList.isEmpty()); |
| 270 | SkASSERT((0 != fCount) || fFreeList.isEmpty()); |
| 271 | |
| 272 | fList.validate(); |
| 273 | fFreeList.validate(); |
| 274 | typename NodeList::Iter iter; |
| 275 | Node* freeNode = iter.init(fFreeList, Iter::kHead_IterStart); |
| 276 | while (freeNode) { |
| 277 | SkASSERT(fFreeList.isInList(freeNode)); |
| 278 | Block* block = freeNode->fBlock; |
| 279 | SkASSERT(block->fNodesInUse > 0 && block->fNodesInUse < fAllocCnt); |
| 280 | |
| 281 | int activeCnt = 0; |
| 282 | int freeCnt = 0; |
| 283 | for (int i = 0; i < fAllocCnt; ++i) { |
| 284 | bool free = fFreeList.isInList(block->fNodes + i); |
| 285 | bool active = fList.isInList(block->fNodes + i); |
| 286 | SkASSERT(free != active); |
| 287 | activeCnt += active; |
| 288 | freeCnt += free; |
| 289 | } |
| 290 | SkASSERT(activeCnt == block->fNodesInUse); |
| 291 | freeNode = iter.next(); |
| 292 | } |
| 293 | |
| 294 | int count = 0; |
| 295 | Node* activeNode = iter.init(fList, Iter::kHead_IterStart); |
| 296 | while (activeNode) { |
| 297 | ++count; |
| 298 | SkASSERT(fList.isInList(activeNode)); |
| 299 | Block* block = activeNode->fBlock; |
| 300 | SkASSERT(block->fNodesInUse > 0 && block->fNodesInUse <= fAllocCnt); |
| 301 | |
| 302 | int activeCnt = 0; |
| 303 | int freeCnt = 0; |
| 304 | for (int i = 0; i < fAllocCnt; ++i) { |
| 305 | bool free = fFreeList.isInList(block->fNodes + i); |
| 306 | bool active = fList.isInList(block->fNodes + i); |
| 307 | SkASSERT(free != active); |
| 308 | activeCnt += active; |
| 309 | freeCnt += free; |
| 310 | } |
| 311 | SkASSERT(activeCnt == block->fNodesInUse); |
| 312 | activeNode = iter.next(); |
| 313 | } |
| 314 | SkASSERT(count == fCount); |
| 315 | #endif |
| 316 | } |
| 317 | |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 318 | // Support in-place initializing of objects inserted into the list via operator new. |
| 319 | friend void* operator new<T>(size_t, |
| 320 | SkTLList* list, |
| 321 | Placement placement, |
| 322 | const Iter& location); |
| 323 | |
| 324 | |
| 325 | // Helpers that insert the node and returns a pointer to where the new object should be init'ed. |
| 326 | void* internalAddBefore(Iter location) { |
| 327 | this->validate(); |
| 328 | Node* node = this->createNode(); |
| 329 | fList.addBefore(node, location.getNode()); |
| 330 | this->validate(); |
| 331 | return node->fObj; |
| 332 | } |
| 333 | |
| 334 | void* internalAddAfter(Iter location) { |
| 335 | this->validate(); |
| 336 | Node* node = this->createNode(); |
| 337 | fList.addAfter(node, location.getNode()); |
| 338 | this->validate(); |
| 339 | return node->fObj; |
| 340 | } |
| 341 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 342 | NodeList fList; |
| 343 | NodeList fFreeList; |
| 344 | int fCount; |
| 345 | int fAllocCnt; |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 346 | |
bsalomon@google.com | bbe5290 | 2012-12-03 18:01:45 +0000 | [diff] [blame] | 347 | }; |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 348 | |
| 349 | // Use the below macros rather than calling this directly |
| 350 | template <typename T> |
| 351 | void *operator new(size_t, SkTLList<T>* list, |
| 352 | typename SkTLList<T>::Placement placement, |
| 353 | const typename SkTLList<T>::Iter& location) { |
| 354 | SkASSERT(NULL != list); |
| 355 | if (SkTLList<T>::kBefore_Placement == placement) { |
| 356 | return list->internalAddBefore(location); |
| 357 | } else { |
| 358 | return list->internalAddAfter(location); |
| 359 | } |
| 360 | } |
| 361 | |
bsalomon@google.com | 8958dc9 | 2012-12-05 14:51:39 +0000 | [diff] [blame] | 362 | // Skia doesn't use C++ exceptions but it may be compiled with them enabled. Having an op delete |
| 363 | // to match the op new silences warnings about missing op delete when a constructor throws an |
| 364 | // exception. |
| 365 | template <typename T> |
| 366 | void operator delete(void*, |
| 367 | SkTLList<T>*, |
| 368 | typename SkTLList<T>::Placement, |
| 369 | const typename SkTLList<T>::Iter&) { |
| 370 | SK_CRASH(); |
| 371 | } |
| 372 | |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 373 | #define SkNEW_INSERT_IN_LLIST_BEFORE(list, location, type_name, args) \ |
bsalomon@google.com | 8182fa0 | 2012-12-04 14:06:06 +0000 | [diff] [blame] | 374 | (new ((list), SkTLList< type_name >::kBefore_Placement, (location)) type_name args) |
bsalomon@google.com | dd3f7a9 | 2012-12-03 19:47:41 +0000 | [diff] [blame] | 375 | |
| 376 | #define SkNEW_INSERT_IN_LLIST_AFTER(list, location, type_name, args) \ |
bsalomon@google.com | 8182fa0 | 2012-12-04 14:06:06 +0000 | [diff] [blame] | 377 | (new ((list), SkTLList< type_name >::kAfter_Placement, (location)) type_name args) |
| 378 | |
| 379 | #define SkNEW_INSERT_AT_LLIST_HEAD(list, type_name, args) \ |
| 380 | SkNEW_INSERT_IN_LLIST_BEFORE((list), (list)->headIter(), type_name, args) |
| 381 | |
| 382 | #define SkNEW_INSERT_AT_LLIST_TAIL(list, type_name, args) \ |
bsalomon@google.com | ebce030 | 2012-12-04 14:48:57 +0000 | [diff] [blame] | 383 | SkNEW_INSERT_IN_LLIST_AFTER((list), (list)->tailIter(), type_name, args) |
| 384 | |
bsalomon@google.com | 4c2443e | 2012-12-06 20:58:57 +0000 | [diff] [blame] | 385 | #endif |