Move SkTInternalLList.h to src/core.

include/core/SkTInternalLList.h

-/*
- * Copyright 2012 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkTInternalLList_DEFINED
-#define SkTInternalLList_DEFINED
-
-#include "SkTypes.h"
-
-/**
- * Helper class to automatically initialize the doubly linked list created pointers.
- */
-template <typename T> class SkPtrWrapper {
-  public:
-      SkPtrWrapper() : fPtr(NULL) {}
-      SkPtrWrapper& operator =(T* ptr) { fPtr = ptr; return *this; }
-      operator T*() const { return fPtr; }
-      T* operator->() { return fPtr; }
-  private:
-      T* fPtr;
-};
-
-
-/**
- * This macro creates the member variables required by the SkTInternalLList class. It should be
- * placed in the private section of any class that will be stored in a double linked list.
- */
-#define SK_DECLARE_INTERNAL_LLIST_INTERFACE(ClassName)              \
-    friend class SkTInternalLList<ClassName>;                       \
-    /* back pointer to the owning list - for debugging */           \
-    SkDEBUGCODE(SkPtrWrapper<SkTInternalLList<ClassName> > fList;)  \
-    SkPtrWrapper<ClassName> fPrev;                                  \
-    SkPtrWrapper<ClassName> fNext
-
-/**
- * This class implements a templated internal doubly linked list data structure.
- */
-template <class T> class SkTInternalLList : SkNoncopyable {
-public:
-    SkTInternalLList()
-        : fHead(NULL)
-        , fTail(NULL) {
-    }
-
-    void remove(T* entry) {
-        SkASSERT(fHead && fTail);
-        SkASSERT(this->isInList(entry));
-
-        T* prev = entry->fPrev;
-        T* next = entry->fNext;
-
-        if (prev) {
-            prev->fNext = next;
-        } else {
-            fHead = next;
-        }
-        if (next) {
-            next->fPrev = prev;
-        } else {
-            fTail = prev;
-        }
-
-        entry->fPrev = NULL;
-        entry->fNext = NULL;
-
-#ifdef SK_DEBUG
-        entry->fList = NULL;
-#endif
-    }
-
-    void addToHead(T* entry) {
-        SkASSERT(NULL == entry->fPrev && NULL == entry->fNext);
-        SkASSERT(NULL == entry->fList);
-
-        entry->fPrev = NULL;
-        entry->fNext = fHead;
-        if (fHead) {
-            fHead->fPrev = entry;
-        }
-        fHead = entry;
-        if (NULL == fTail) {
-            fTail = entry;
-        }
-
-#ifdef SK_DEBUG
-        entry->fList = this;
-#endif
-    }
-
-    void addToTail(T* entry) {
-        SkASSERT(NULL == entry->fPrev && NULL == entry->fNext);
-        SkASSERT(NULL == entry->fList);
-
-        entry->fPrev = fTail;
-        entry->fNext = NULL;
-        if (fTail) {
-            fTail->fNext = entry;
-        }
-        fTail = entry;
-        if (NULL == fHead) {
-            fHead = entry;
-        }
-
-#ifdef SK_DEBUG
-        entry->fList = this;
-#endif
-    }
-
-    /**
-     * Inserts a new list entry before an existing list entry. The new entry must not already be
-     * a member of this or any other list. If existingEntry is NULL then the new entry is added
-     * at the tail.
-     */
-    void addBefore(T* newEntry, T* existingEntry) {
-        SkASSERT(newEntry);
-
-        if (NULL == existingEntry) {
-            this->addToTail(newEntry);
-            return;
-        }
-
-        SkASSERT(this->isInList(existingEntry));
-        newEntry->fNext = existingEntry;
-        T* prev = existingEntry->fPrev;
-        existingEntry->fPrev = newEntry;
-        newEntry->fPrev = prev;
-        if (NULL == prev) {
-            SkASSERT(fHead == existingEntry);
-            fHead = newEntry;
-        } else {
-            prev->fNext = newEntry;
-        }
-#ifdef SK_DEBUG
-        newEntry->fList = this;
-#endif
-    }
-
-    /**
-     * Inserts a new list entry after an existing list entry. The new entry must not already be
-     * a member of this or any other list. If existingEntry is NULL then the new entry is added
-     * at the head.
-     */
-    void addAfter(T* newEntry, T* existingEntry) {
-        SkASSERT(newEntry);
-
-        if (NULL == existingEntry) {
-            this->addToHead(newEntry);
-            return;
-        }
-
-        SkASSERT(this->isInList(existingEntry));
-        newEntry->fPrev = existingEntry;
-        T* next = existingEntry->fNext;
-        existingEntry->fNext = newEntry;
-        newEntry->fNext = next;
-        if (NULL == next) {
-            SkASSERT(fTail == existingEntry);
-            fTail = newEntry;
-        } else {
-            next->fPrev = newEntry;
-        }
-#ifdef SK_DEBUG
-        newEntry->fList = this;
-#endif
-    }
-
-    bool isEmpty() const {
-        return NULL == fHead && NULL == fTail;
-    }
-
-    T* head() { return fHead; }
-    T* tail() { return fTail; }
-
-    class Iter {
-    public:
-        enum IterStart {
-            kHead_IterStart,
-            kTail_IterStart
-        };
-
-        Iter() : fCurr(NULL) {}
-        Iter(const Iter& iter) : fCurr(iter.fCurr) {}
-        Iter& operator= (const Iter& iter) { fCurr = iter.fCurr; return *this; }
-
-        T* init(const SkTInternalLList& list, IterStart startLoc) {
-            if (kHead_IterStart == startLoc) {
-                fCurr = list.fHead;
-            } else {
-                SkASSERT(kTail_IterStart == startLoc);
-                fCurr = list.fTail;
-            }
-
-            return fCurr;
-        }
-
-        T* get() { return fCurr; }
-
-        /**
-         * Return the next/previous element in the list or NULL if at the end.
-         */
-        T* next() {
-            if (NULL == fCurr) {
-                return NULL;
-            }
-
-            fCurr = fCurr->fNext;
-            return fCurr;
-        }
-
-        T* prev() {
-            if (NULL == fCurr) {
-                return NULL;
-            }
-
-            fCurr = fCurr->fPrev;
-            return fCurr;
-        }
-
-    private:
-        T* fCurr;
-    };
-
-#ifdef SK_DEBUG
-    void validate() const {
-        SkASSERT(!fHead == !fTail);
-        Iter iter;
-        for (T* item = iter.init(*this, Iter::kHead_IterStart); item; item = iter.next()) {
-            SkASSERT(this->isInList(item));
-            if (NULL == item->fPrev) {
-                SkASSERT(fHead == item);
-            } else {
-                SkASSERT(item->fPrev->fNext == item);
-            }
-            if (NULL == item->fNext) {
-                SkASSERT(fTail == item);
-            } else {
-                SkASSERT(item->fNext->fPrev == item);
-            }
-        }
-    }
-
-    /**
-     * Debugging-only method that uses the list back pointer to check if 'entry' is indeed in 'this'
-     * list.
-     */
-    bool isInList(const T* entry) const {
-        return entry->fList == this;
-    }
-
-    /**
-     * Debugging-only method that laboriously counts the list entries.
-     */
-    int countEntries() const {
-        int count = 0;
-        for (T* entry = fHead; entry; entry = entry->fNext) {
-            ++count;
-        }
-        return count;
-    }
-#endif // SK_DEBUG
-
-private:
-    T* fHead;
-    T* fTail;
-
-    typedef SkNoncopyable INHERITED;
-};
-
-#endif