| 1 | /* |
| 2 | vectorbuffer.cpp |
| 3 | yet another circle buffer |
| 4 | |
| 5 | Markus Mertama |
| 6 | */ |
| 7 | |
| 8 | #ifndef __VECTORBUFFER_H__ |
| 9 | #define __VECTORBUFFER_H__ |
| 10 | |
| 11 | #include<e32std.h> |
| 12 | #define VLOG(x) |
| 13 | #define VECPANIC(x) VectorPanic(x, __LINE__) |
| 14 | void VectorPanic(TInt, TInt); |
| 15 | |
| 16 | |
| 17 | //int DEBUG_INT; |
| 18 | |
| 19 | NONSHARABLE_CLASS(TNodeBuffer) |
| 20 | { |
| 21 | public: |
| 22 | protected: |
| 23 | NONSHARABLE_CLASS(TNode) |
| 24 | { |
| 25 | public: |
| 26 | static TNode* Empty(TUint8* iBuffer); |
| 27 | static TNode* New(TNode* aPrev, const TDesC8& aData); |
| 28 | const TUint8* Ptr() const; |
| 29 | TInt Size() const; |
| 30 | inline TNode* Succ(); |
| 31 | static void SetSucc(TNode*& aNode); |
| 32 | void Terminator(TNode* aNode); |
| 33 | private: |
| 34 | TNode* iSucc; |
| 35 | }; |
| 36 | }; |
| 37 | |
| 38 | inline TNodeBuffer::TNode* TNodeBuffer::TNode::Succ() |
| 39 | { |
| 40 | return iSucc; |
| 41 | } |
| 42 | |
| 43 | template <TInt C> |
| 44 | NONSHARABLE_CLASS(TVectorBuffer) : public TNodeBuffer |
| 45 | { |
| 46 | public: |
| 47 | TVectorBuffer(); |
| 48 | TInt Append(const TDesC8& aData); |
| 49 | // TInt AppendOverwrite(const TDesC8& aData); |
| 50 | TPtrC8 Shift(); |
| 51 | TPtrC8 operator[](TInt aIndex) const; |
| 52 | TInt Size() const; |
| 53 | private: |
| 54 | TInt GetRoom(TInt aSize) const; |
| 55 | TInt Unreserved() const; |
| 56 | private: |
| 57 | TNode* iTop; |
| 58 | TNode* iBottom; |
| 59 | TInt iSize; |
| 60 | TUint8 iBuffer[C]; |
| 61 | }; |
| 62 | |
| 63 | template <TInt C> |
| 64 | TVectorBuffer<C>::TVectorBuffer() : iSize(0) |
| 65 | { |
| 66 | Mem::FillZ(iBuffer, C); |
| 67 | iTop = TNode::Empty(iBuffer); //these points to buffer |
| 68 | iBottom = TNode::Empty(iBuffer); |
| 69 | } |
| 70 | |
| 71 | template<TInt C > |
| 72 | TInt TVectorBuffer<C>::Unreserved() const |
| 73 | { |
| 74 | __ASSERT_DEBUG(iBottom < iBottom->Succ(), VECPANIC(KErrCorrupt)); |
| 75 | const TInt bytesbetween = |
| 76 | reinterpret_cast<const TUint8*>(iBottom->Succ()) - |
| 77 | reinterpret_cast<const TUint8*>(iTop); |
| 78 | const TInt topsize = sizeof(TNode); |
| 79 | if(bytesbetween > 0) //bytesbetween is room between bottom and top |
| 80 | { //therefore free room is subracted from free space |
| 81 | |
| 82 | const TInt room = C - bytesbetween - topsize; |
| 83 | return room; |
| 84 | } |
| 85 | if(bytesbetween == 0) |
| 86 | { |
| 87 | |
| 88 | if(Size() > 0) |
| 89 | return 0; |
| 90 | else |
| 91 | return C - topsize; |
| 92 | } |
| 93 | const TInt room = -bytesbetween - topsize; //free is space between pointers |
| 94 | return room; |
| 95 | } |
| 96 | |
| 97 | template <TInt C> |
| 98 | TInt TVectorBuffer<C>::GetRoom(TInt aSize) const |
| 99 | { |
| 100 | const TInt bytesnew = sizeof(TNode) + aSize; |
| 101 | const TInt room = Unreserved() - bytesnew; |
| 102 | return room; |
| 103 | } |
| 104 | |
| 105 | template <TInt C> |
| 106 | TInt TVectorBuffer<C>::Append(const TDesC8& aData) //ei ole ok! |
| 107 | { |
| 108 | const TInt len = aData.Length(); |
| 109 | if(GetRoom(len) < 0) |
| 110 | { |
| 111 | return KErrOverflow; |
| 112 | } |
| 113 | if(iBottom->Succ()->Ptr() - iBuffer > (C - (len + TInt(sizeof(TNode))))) |
| 114 | { |
| 115 | VLOG("rc"); |
| 116 | // RDebug::Print(_L("vector: append")); |
| 117 | TNode* p = TNode::Empty(iBuffer); |
| 118 | iBottom->Terminator(p); |
| 119 | iBottom = p; |
| 120 | return Append(aData); |
| 121 | // Append(); |
| 122 | // iBottom = TNode::New(p, aData); //just append something into end |
| 123 | } |
| 124 | |
| 125 | //DEBUG_INT++; |
| 126 | |
| 127 | iBottom = TNode::New(iBottom, aData); |
| 128 | |
| 129 | iSize += len; |
| 130 | return KErrNone; |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | template <TInt C> |
| 135 | TInt TVectorBuffer<C>::AppendOverwrite(const TDesC8& aData) //ei ole ok! |
| 136 | { |
| 137 | while(Append(aData) == KErrOverflow) |
| 138 | { |
| 139 | if(iTop->Succ() == NULL) |
| 140 | { |
| 141 | return KErrUnderflow; |
| 142 | } |
| 143 | //Shift(); //data is lost |
| 144 | } |
| 145 | return KErrNone; |
| 146 | } |
| 147 | */ |
| 148 | template <TInt C> |
| 149 | TPtrC8 TVectorBuffer<C>::Shift() |
| 150 | { |
| 151 | __ASSERT_ALWAYS(iTop->Succ() != NULL, VECPANIC(KErrUnderflow)); //can never pass-by bottom |
| 152 | TNode* node = iTop; |
| 153 | iTop = iTop->Succ(); |
| 154 | if(iTop > node) |
| 155 | { |
| 156 | // DEBUG_INT--; |
| 157 | iSize -= node->Size(); |
| 158 | return TPtrC8(node->Ptr(), node->Size()); |
| 159 | } |
| 160 | else |
| 161 | { |
| 162 | // RDebug::Print(_L("vector: shift")); |
| 163 | return Shift(); //this happens when buffer is terminated, and data lies in next |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | template <TInt C> |
| 168 | TInt TVectorBuffer<C>::Size() const |
| 169 | { |
| 170 | return iSize; |
| 171 | } |
| 172 | |
| 173 | template <TInt C> |
| 174 | TPtrC8 TVectorBuffer<C>::operator[](TInt aIndex) const |
| 175 | { |
| 176 | TInt index = 0; |
| 177 | TNode* t = iTop->Size() > 0 ? iTop : iTop->Succ(); //eliminate terminator |
| 178 | while(index < aIndex) |
| 179 | { |
| 180 | TNode* nt = t->Succ(); |
| 181 | if(nt < t) |
| 182 | { |
| 183 | nt = nt->Succ(); |
| 184 | } |
| 185 | t = nt; |
| 186 | if(t->Size() > 0) |
| 187 | index++; |
| 188 | __ASSERT_ALWAYS(t->Succ() != NULL, VECPANIC(KErrUnderflow)); //can never pass-by bottom |
| 189 | } |
| 190 | return t->Ptr(); |
| 191 | } |
| 192 | |
| 193 | |
| 194 | template <class T, TInt C> |
| 195 | NONSHARABLE_CLASS(TVector) : public TVectorBuffer<C * sizeof(T)> |
| 196 | { |
| 197 | public: |
| 198 | TVector(); |
| 199 | TInt Append(const T& aData); |
| 200 | const T& Shift(); |
| 201 | TInt Size() const; |
| 202 | const T& operator[](TInt aIndex) const; |
| 203 | }; |
| 204 | |
| 205 | template <class T, TInt C> |
| 206 | TVector<T, C>::TVector() : TVectorBuffer<C * sizeof(T)>() |
| 207 | { |
| 208 | } |
| 209 | |
| 210 | template <class T, TInt C> |
| 211 | TInt TVector<T, C>::Append(const T& aData) |
| 212 | { |
| 213 | const TPckgC<T> data(aData); |
| 214 | return TVectorBuffer<C * sizeof(T)>::Append(data); |
| 215 | } |
| 216 | |
| 217 | template <class T, TInt C> |
| 218 | const T& TVector<T, C>::Shift() |
| 219 | { |
| 220 | const TPtrC8 ptr = TVectorBuffer<C * sizeof(T)>::Shift(); |
| 221 | return *(reinterpret_cast<const T*>(ptr.Ptr())); |
| 222 | } |
| 223 | |
| 224 | |
| 225 | template <class T, TInt C> |
| 226 | TInt TVector<T, C>::Size() const |
| 227 | { |
| 228 | return TVectorBuffer<C * sizeof(T)>::Size() / sizeof(T); |
| 229 | } |
| 230 | |
| 231 | template <class T, TInt C> |
| 232 | const T& TVector<T, C>::operator[](TInt aIndex) const |
| 233 | { |
| 234 | const TPtrC8 ptr = TVectorBuffer<C * sizeof(T)>::operator[](aIndex); |
| 235 | return *(reinterpret_cast<const T*>(ptr.Ptr())); |
| 236 | } |
| 237 | |
| 238 | #endif |
| 239 | |
| 240 | |