Preliminary main mbed library for nexpaq development
features/FEATURE_BLE/ble/CallChainOfFunctionPointersWithContext.h@1:d96dbedaebdb, 2016-11-04 (annotated)
- Committer:
- nexpaq
- Date:
- Fri Nov 04 20:54:50 2016 +0000
- Revision:
- 1:d96dbedaebdb
- Parent:
- 0:6c56fb4bc5f0
Removed extra directories for other platforms
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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nexpaq | 0:6c56fb4bc5f0 | 1 | /* mbed Microcontroller Library |
nexpaq | 0:6c56fb4bc5f0 | 2 | * Copyright (c) 2006-2013 ARM Limited |
nexpaq | 0:6c56fb4bc5f0 | 3 | * |
nexpaq | 0:6c56fb4bc5f0 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
nexpaq | 0:6c56fb4bc5f0 | 5 | * you may not use this file except in compliance with the License. |
nexpaq | 0:6c56fb4bc5f0 | 6 | * You may obtain a copy of the License at |
nexpaq | 0:6c56fb4bc5f0 | 7 | * |
nexpaq | 0:6c56fb4bc5f0 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
nexpaq | 0:6c56fb4bc5f0 | 9 | * |
nexpaq | 0:6c56fb4bc5f0 | 10 | * Unless required by applicable law or agreed to in writing, software |
nexpaq | 0:6c56fb4bc5f0 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
nexpaq | 0:6c56fb4bc5f0 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
nexpaq | 0:6c56fb4bc5f0 | 13 | * See the License for the specific language governing permissions and |
nexpaq | 0:6c56fb4bc5f0 | 14 | * limitations under the License. |
nexpaq | 0:6c56fb4bc5f0 | 15 | */ |
nexpaq | 0:6c56fb4bc5f0 | 16 | #ifndef MBED_CALLCHAIN_OF_FUNCTION_POINTERS_WITH_CONTEXT_H |
nexpaq | 0:6c56fb4bc5f0 | 17 | #define MBED_CALLCHAIN_OF_FUNCTION_POINTERS_WITH_CONTEXT_H |
nexpaq | 0:6c56fb4bc5f0 | 18 | |
nexpaq | 0:6c56fb4bc5f0 | 19 | #include <string.h> |
nexpaq | 0:6c56fb4bc5f0 | 20 | #include "FunctionPointerWithContext.h" |
nexpaq | 0:6c56fb4bc5f0 | 21 | #include "SafeBool.h" |
nexpaq | 0:6c56fb4bc5f0 | 22 | |
nexpaq | 0:6c56fb4bc5f0 | 23 | |
nexpaq | 0:6c56fb4bc5f0 | 24 | /** Group one or more functions in an instance of a CallChainOfFunctionPointersWithContext, then call them in |
nexpaq | 0:6c56fb4bc5f0 | 25 | * sequence using CallChainOfFunctionPointersWithContext::call(). Used mostly by the interrupt chaining code, |
nexpaq | 0:6c56fb4bc5f0 | 26 | * but can be used for other purposes. |
nexpaq | 0:6c56fb4bc5f0 | 27 | * |
nexpaq | 0:6c56fb4bc5f0 | 28 | * Example: |
nexpaq | 0:6c56fb4bc5f0 | 29 | * @code |
nexpaq | 0:6c56fb4bc5f0 | 30 | * |
nexpaq | 0:6c56fb4bc5f0 | 31 | * CallChainOfFunctionPointersWithContext<void *> chain; |
nexpaq | 0:6c56fb4bc5f0 | 32 | * |
nexpaq | 0:6c56fb4bc5f0 | 33 | * void first(void *context) { |
nexpaq | 0:6c56fb4bc5f0 | 34 | * printf("'first' function.\n"); |
nexpaq | 0:6c56fb4bc5f0 | 35 | * } |
nexpaq | 0:6c56fb4bc5f0 | 36 | * |
nexpaq | 0:6c56fb4bc5f0 | 37 | * void second(void *context) { |
nexpaq | 0:6c56fb4bc5f0 | 38 | * printf("'second' function.\n"); |
nexpaq | 0:6c56fb4bc5f0 | 39 | * } |
nexpaq | 0:6c56fb4bc5f0 | 40 | * |
nexpaq | 0:6c56fb4bc5f0 | 41 | * class Test { |
nexpaq | 0:6c56fb4bc5f0 | 42 | * public: |
nexpaq | 0:6c56fb4bc5f0 | 43 | * void f(void *context) { |
nexpaq | 0:6c56fb4bc5f0 | 44 | * printf("A::f (class member).\n"); |
nexpaq | 0:6c56fb4bc5f0 | 45 | * } |
nexpaq | 0:6c56fb4bc5f0 | 46 | * }; |
nexpaq | 0:6c56fb4bc5f0 | 47 | * |
nexpaq | 0:6c56fb4bc5f0 | 48 | * int main() { |
nexpaq | 0:6c56fb4bc5f0 | 49 | * Test test; |
nexpaq | 0:6c56fb4bc5f0 | 50 | * |
nexpaq | 0:6c56fb4bc5f0 | 51 | * chain.add(second); |
nexpaq | 0:6c56fb4bc5f0 | 52 | * chain.add_front(first); |
nexpaq | 0:6c56fb4bc5f0 | 53 | * chain.add(&test, &Test::f); |
nexpaq | 0:6c56fb4bc5f0 | 54 | * chain.call(); |
nexpaq | 0:6c56fb4bc5f0 | 55 | * } |
nexpaq | 0:6c56fb4bc5f0 | 56 | * @endcode |
nexpaq | 0:6c56fb4bc5f0 | 57 | */ |
nexpaq | 0:6c56fb4bc5f0 | 58 | template <typename ContextType> |
nexpaq | 0:6c56fb4bc5f0 | 59 | class CallChainOfFunctionPointersWithContext : public SafeBool<CallChainOfFunctionPointersWithContext<ContextType> > { |
nexpaq | 0:6c56fb4bc5f0 | 60 | public: |
nexpaq | 0:6c56fb4bc5f0 | 61 | /** |
nexpaq | 0:6c56fb4bc5f0 | 62 | * The type of each callback in the callchain. |
nexpaq | 0:6c56fb4bc5f0 | 63 | */ |
nexpaq | 0:6c56fb4bc5f0 | 64 | typedef FunctionPointerWithContext<ContextType> *pFunctionPointerWithContext_t; |
nexpaq | 0:6c56fb4bc5f0 | 65 | |
nexpaq | 0:6c56fb4bc5f0 | 66 | public: |
nexpaq | 0:6c56fb4bc5f0 | 67 | /** |
nexpaq | 0:6c56fb4bc5f0 | 68 | * Create an empty chain. |
nexpaq | 0:6c56fb4bc5f0 | 69 | */ |
nexpaq | 0:6c56fb4bc5f0 | 70 | CallChainOfFunctionPointersWithContext() : chainHead(NULL) { |
nexpaq | 0:6c56fb4bc5f0 | 71 | /* empty */ |
nexpaq | 0:6c56fb4bc5f0 | 72 | } |
nexpaq | 0:6c56fb4bc5f0 | 73 | |
nexpaq | 0:6c56fb4bc5f0 | 74 | virtual ~CallChainOfFunctionPointersWithContext() { |
nexpaq | 0:6c56fb4bc5f0 | 75 | clear(); |
nexpaq | 0:6c56fb4bc5f0 | 76 | } |
nexpaq | 0:6c56fb4bc5f0 | 77 | |
nexpaq | 0:6c56fb4bc5f0 | 78 | /** |
nexpaq | 0:6c56fb4bc5f0 | 79 | * Add a function at the front of the chain. |
nexpaq | 0:6c56fb4bc5f0 | 80 | * |
nexpaq | 0:6c56fb4bc5f0 | 81 | * @param[in] function |
nexpaq | 0:6c56fb4bc5f0 | 82 | * A pointer to a void function. |
nexpaq | 0:6c56fb4bc5f0 | 83 | * |
nexpaq | 0:6c56fb4bc5f0 | 84 | * @return The function object created for @p function. |
nexpaq | 0:6c56fb4bc5f0 | 85 | */ |
nexpaq | 0:6c56fb4bc5f0 | 86 | pFunctionPointerWithContext_t add(void (*function)(ContextType context)) { |
nexpaq | 0:6c56fb4bc5f0 | 87 | return common_add(new FunctionPointerWithContext<ContextType>(function)); |
nexpaq | 0:6c56fb4bc5f0 | 88 | } |
nexpaq | 0:6c56fb4bc5f0 | 89 | |
nexpaq | 0:6c56fb4bc5f0 | 90 | /** |
nexpaq | 0:6c56fb4bc5f0 | 91 | * Add a function at the front of the chain. |
nexpaq | 0:6c56fb4bc5f0 | 92 | * |
nexpaq | 0:6c56fb4bc5f0 | 93 | * @param[in] tptr |
nexpaq | 0:6c56fb4bc5f0 | 94 | * Pointer to the object to call the member function on. |
nexpaq | 0:6c56fb4bc5f0 | 95 | * @param[in] mptr |
nexpaq | 0:6c56fb4bc5f0 | 96 | * Pointer to the member function to be called. |
nexpaq | 0:6c56fb4bc5f0 | 97 | * |
nexpaq | 0:6c56fb4bc5f0 | 98 | * @return The function object created for @p tptr and @p mptr. |
nexpaq | 0:6c56fb4bc5f0 | 99 | */ |
nexpaq | 0:6c56fb4bc5f0 | 100 | template<typename T> |
nexpaq | 0:6c56fb4bc5f0 | 101 | pFunctionPointerWithContext_t add(T *tptr, void (T::*mptr)(ContextType context)) { |
nexpaq | 0:6c56fb4bc5f0 | 102 | return common_add(new FunctionPointerWithContext<ContextType>(tptr, mptr)); |
nexpaq | 0:6c56fb4bc5f0 | 103 | } |
nexpaq | 0:6c56fb4bc5f0 | 104 | |
nexpaq | 0:6c56fb4bc5f0 | 105 | /** |
nexpaq | 0:6c56fb4bc5f0 | 106 | * Add a function at the front of the chain. |
nexpaq | 0:6c56fb4bc5f0 | 107 | * |
nexpaq | 0:6c56fb4bc5f0 | 108 | * @param[in] func |
nexpaq | 0:6c56fb4bc5f0 | 109 | * The FunctionPointerWithContext to add. |
nexpaq | 0:6c56fb4bc5f0 | 110 | * |
nexpaq | 0:6c56fb4bc5f0 | 111 | * @return The function object created for @p func. |
nexpaq | 0:6c56fb4bc5f0 | 112 | */ |
nexpaq | 0:6c56fb4bc5f0 | 113 | pFunctionPointerWithContext_t add(const FunctionPointerWithContext<ContextType>& func) { |
nexpaq | 0:6c56fb4bc5f0 | 114 | return common_add(new FunctionPointerWithContext<ContextType>(func)); |
nexpaq | 0:6c56fb4bc5f0 | 115 | } |
nexpaq | 0:6c56fb4bc5f0 | 116 | |
nexpaq | 0:6c56fb4bc5f0 | 117 | /** |
nexpaq | 0:6c56fb4bc5f0 | 118 | * Detach a function pointer from a callchain. |
nexpaq | 0:6c56fb4bc5f0 | 119 | * |
nexpaq | 0:6c56fb4bc5f0 | 120 | * @param[in] toDetach |
nexpaq | 0:6c56fb4bc5f0 | 121 | * FunctionPointerWithContext to detach from this callchain. |
nexpaq | 0:6c56fb4bc5f0 | 122 | * |
nexpaq | 0:6c56fb4bc5f0 | 123 | * @return true if a function pointer has been detached and false otherwise. |
nexpaq | 0:6c56fb4bc5f0 | 124 | * |
nexpaq | 0:6c56fb4bc5f0 | 125 | * @note It is safe to remove a function pointer while the chain is |
nexpaq | 0:6c56fb4bc5f0 | 126 | * traversed by call(ContextType). |
nexpaq | 0:6c56fb4bc5f0 | 127 | */ |
nexpaq | 0:6c56fb4bc5f0 | 128 | bool detach(const FunctionPointerWithContext<ContextType>& toDetach) { |
nexpaq | 0:6c56fb4bc5f0 | 129 | pFunctionPointerWithContext_t current = chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 130 | pFunctionPointerWithContext_t previous = NULL; |
nexpaq | 0:6c56fb4bc5f0 | 131 | |
nexpaq | 0:6c56fb4bc5f0 | 132 | while (current) { |
nexpaq | 0:6c56fb4bc5f0 | 133 | if(*current == toDetach) { |
nexpaq | 0:6c56fb4bc5f0 | 134 | if(previous == NULL) { |
nexpaq | 0:6c56fb4bc5f0 | 135 | if(currentCalled == current) { |
nexpaq | 0:6c56fb4bc5f0 | 136 | currentCalled = NULL; |
nexpaq | 0:6c56fb4bc5f0 | 137 | } |
nexpaq | 0:6c56fb4bc5f0 | 138 | chainHead = current->getNext(); |
nexpaq | 0:6c56fb4bc5f0 | 139 | } else { |
nexpaq | 0:6c56fb4bc5f0 | 140 | if(currentCalled == current) { |
nexpaq | 0:6c56fb4bc5f0 | 141 | currentCalled = previous; |
nexpaq | 0:6c56fb4bc5f0 | 142 | } |
nexpaq | 0:6c56fb4bc5f0 | 143 | previous->chainAsNext(current->getNext()); |
nexpaq | 0:6c56fb4bc5f0 | 144 | } |
nexpaq | 0:6c56fb4bc5f0 | 145 | delete current; |
nexpaq | 0:6c56fb4bc5f0 | 146 | return true; |
nexpaq | 0:6c56fb4bc5f0 | 147 | } |
nexpaq | 0:6c56fb4bc5f0 | 148 | |
nexpaq | 0:6c56fb4bc5f0 | 149 | previous = current; |
nexpaq | 0:6c56fb4bc5f0 | 150 | current = current->getNext(); |
nexpaq | 0:6c56fb4bc5f0 | 151 | } |
nexpaq | 0:6c56fb4bc5f0 | 152 | |
nexpaq | 0:6c56fb4bc5f0 | 153 | return false; |
nexpaq | 0:6c56fb4bc5f0 | 154 | } |
nexpaq | 0:6c56fb4bc5f0 | 155 | |
nexpaq | 0:6c56fb4bc5f0 | 156 | /** |
nexpaq | 0:6c56fb4bc5f0 | 157 | * Clear the call chain (remove all functions in the chain). |
nexpaq | 0:6c56fb4bc5f0 | 158 | */ |
nexpaq | 0:6c56fb4bc5f0 | 159 | void clear(void) { |
nexpaq | 0:6c56fb4bc5f0 | 160 | pFunctionPointerWithContext_t fptr = chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 161 | while (fptr) { |
nexpaq | 0:6c56fb4bc5f0 | 162 | pFunctionPointerWithContext_t deadPtr = fptr; |
nexpaq | 0:6c56fb4bc5f0 | 163 | fptr = deadPtr->getNext(); |
nexpaq | 0:6c56fb4bc5f0 | 164 | delete deadPtr; |
nexpaq | 0:6c56fb4bc5f0 | 165 | } |
nexpaq | 0:6c56fb4bc5f0 | 166 | |
nexpaq | 0:6c56fb4bc5f0 | 167 | chainHead = NULL; |
nexpaq | 0:6c56fb4bc5f0 | 168 | } |
nexpaq | 0:6c56fb4bc5f0 | 169 | |
nexpaq | 0:6c56fb4bc5f0 | 170 | /** |
nexpaq | 0:6c56fb4bc5f0 | 171 | * Check whether the callchain contains any callbacks. |
nexpaq | 0:6c56fb4bc5f0 | 172 | * |
nexpaq | 0:6c56fb4bc5f0 | 173 | * @return true if the callchain is not empty and false otherwise. |
nexpaq | 0:6c56fb4bc5f0 | 174 | */ |
nexpaq | 0:6c56fb4bc5f0 | 175 | bool hasCallbacksAttached(void) const { |
nexpaq | 0:6c56fb4bc5f0 | 176 | return (chainHead != NULL); |
nexpaq | 0:6c56fb4bc5f0 | 177 | } |
nexpaq | 0:6c56fb4bc5f0 | 178 | |
nexpaq | 0:6c56fb4bc5f0 | 179 | /** |
nexpaq | 0:6c56fb4bc5f0 | 180 | * Call all the functions in the chain in sequence. |
nexpaq | 0:6c56fb4bc5f0 | 181 | */ |
nexpaq | 0:6c56fb4bc5f0 | 182 | void call(ContextType context) { |
nexpaq | 0:6c56fb4bc5f0 | 183 | ((const CallChainOfFunctionPointersWithContext*) this)->call(context); |
nexpaq | 0:6c56fb4bc5f0 | 184 | } |
nexpaq | 0:6c56fb4bc5f0 | 185 | |
nexpaq | 0:6c56fb4bc5f0 | 186 | /** |
nexpaq | 0:6c56fb4bc5f0 | 187 | * Same as call() above, but const. |
nexpaq | 0:6c56fb4bc5f0 | 188 | */ |
nexpaq | 0:6c56fb4bc5f0 | 189 | void call(ContextType context) const { |
nexpaq | 0:6c56fb4bc5f0 | 190 | currentCalled = chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 191 | |
nexpaq | 0:6c56fb4bc5f0 | 192 | while(currentCalled) { |
nexpaq | 0:6c56fb4bc5f0 | 193 | currentCalled->call(context); |
nexpaq | 0:6c56fb4bc5f0 | 194 | // if this was the head and the call removed the head |
nexpaq | 0:6c56fb4bc5f0 | 195 | if(currentCalled == NULL) { |
nexpaq | 0:6c56fb4bc5f0 | 196 | currentCalled = chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 197 | } else { |
nexpaq | 0:6c56fb4bc5f0 | 198 | currentCalled = currentCalled->getNext(); |
nexpaq | 0:6c56fb4bc5f0 | 199 | } |
nexpaq | 0:6c56fb4bc5f0 | 200 | } |
nexpaq | 0:6c56fb4bc5f0 | 201 | } |
nexpaq | 0:6c56fb4bc5f0 | 202 | |
nexpaq | 0:6c56fb4bc5f0 | 203 | /** |
nexpaq | 0:6c56fb4bc5f0 | 204 | * Same as call(), but with function call operator. |
nexpaq | 0:6c56fb4bc5f0 | 205 | * @code |
nexpaq | 0:6c56fb4bc5f0 | 206 | * |
nexpaq | 0:6c56fb4bc5f0 | 207 | * void first(bool); |
nexpaq | 0:6c56fb4bc5f0 | 208 | * void second(bool); |
nexpaq | 0:6c56fb4bc5f0 | 209 | * |
nexpaq | 0:6c56fb4bc5f0 | 210 | * CallChainOfFunctionPointerWithContext<bool> foo; |
nexpaq | 0:6c56fb4bc5f0 | 211 | * |
nexpaq | 0:6c56fb4bc5f0 | 212 | * foo.attach(first); |
nexpaq | 0:6c56fb4bc5f0 | 213 | * foo.attach(second); |
nexpaq | 0:6c56fb4bc5f0 | 214 | * |
nexpaq | 0:6c56fb4bc5f0 | 215 | * // call the callchain like a function |
nexpaq | 0:6c56fb4bc5f0 | 216 | * foo(true); |
nexpaq | 0:6c56fb4bc5f0 | 217 | * |
nexpaq | 0:6c56fb4bc5f0 | 218 | * @endcode |
nexpaq | 0:6c56fb4bc5f0 | 219 | */ |
nexpaq | 0:6c56fb4bc5f0 | 220 | void operator()(ContextType context) const { |
nexpaq | 0:6c56fb4bc5f0 | 221 | call(context); |
nexpaq | 0:6c56fb4bc5f0 | 222 | } |
nexpaq | 0:6c56fb4bc5f0 | 223 | |
nexpaq | 0:6c56fb4bc5f0 | 224 | /** |
nexpaq | 0:6c56fb4bc5f0 | 225 | * Bool conversion operation. |
nexpaq | 0:6c56fb4bc5f0 | 226 | * |
nexpaq | 0:6c56fb4bc5f0 | 227 | * @return true if the callchain is not empty and false otherwise. |
nexpaq | 0:6c56fb4bc5f0 | 228 | */ |
nexpaq | 0:6c56fb4bc5f0 | 229 | bool toBool() const { |
nexpaq | 0:6c56fb4bc5f0 | 230 | return chainHead != NULL; |
nexpaq | 0:6c56fb4bc5f0 | 231 | } |
nexpaq | 0:6c56fb4bc5f0 | 232 | |
nexpaq | 0:6c56fb4bc5f0 | 233 | private: |
nexpaq | 0:6c56fb4bc5f0 | 234 | /** |
nexpaq | 0:6c56fb4bc5f0 | 235 | * Add a callback to the head of the callchain. |
nexpaq | 0:6c56fb4bc5f0 | 236 | * |
nexpaq | 0:6c56fb4bc5f0 | 237 | * @return A pointer to the head of the callchain. |
nexpaq | 0:6c56fb4bc5f0 | 238 | */ |
nexpaq | 0:6c56fb4bc5f0 | 239 | pFunctionPointerWithContext_t common_add(pFunctionPointerWithContext_t pf) { |
nexpaq | 0:6c56fb4bc5f0 | 240 | if (chainHead == NULL) { |
nexpaq | 0:6c56fb4bc5f0 | 241 | chainHead = pf; |
nexpaq | 0:6c56fb4bc5f0 | 242 | } else { |
nexpaq | 0:6c56fb4bc5f0 | 243 | pf->chainAsNext(chainHead); |
nexpaq | 0:6c56fb4bc5f0 | 244 | chainHead = pf; |
nexpaq | 0:6c56fb4bc5f0 | 245 | } |
nexpaq | 0:6c56fb4bc5f0 | 246 | |
nexpaq | 0:6c56fb4bc5f0 | 247 | return chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 248 | } |
nexpaq | 0:6c56fb4bc5f0 | 249 | |
nexpaq | 0:6c56fb4bc5f0 | 250 | private: |
nexpaq | 0:6c56fb4bc5f0 | 251 | /** |
nexpaq | 0:6c56fb4bc5f0 | 252 | * A pointer to the first callback in the callchain or NULL if the callchain is empty. |
nexpaq | 0:6c56fb4bc5f0 | 253 | */ |
nexpaq | 0:6c56fb4bc5f0 | 254 | pFunctionPointerWithContext_t chainHead; |
nexpaq | 0:6c56fb4bc5f0 | 255 | |
nexpaq | 0:6c56fb4bc5f0 | 256 | /** |
nexpaq | 0:6c56fb4bc5f0 | 257 | * Iterator during a function call, this has to be mutable because the call function is const. |
nexpaq | 0:6c56fb4bc5f0 | 258 | * |
nexpaq | 0:6c56fb4bc5f0 | 259 | * @note Mutable is the correct behaviour here, the iterator never leaks outside the object. |
nexpaq | 0:6c56fb4bc5f0 | 260 | * so the object can still be seen as logically const even if it is modified. |
nexpaq | 0:6c56fb4bc5f0 | 261 | */ |
nexpaq | 0:6c56fb4bc5f0 | 262 | mutable pFunctionPointerWithContext_t currentCalled; |
nexpaq | 0:6c56fb4bc5f0 | 263 | |
nexpaq | 0:6c56fb4bc5f0 | 264 | |
nexpaq | 0:6c56fb4bc5f0 | 265 | /* Disallow copy constructor and assignment operators. */ |
nexpaq | 0:6c56fb4bc5f0 | 266 | private: |
nexpaq | 0:6c56fb4bc5f0 | 267 | CallChainOfFunctionPointersWithContext(const CallChainOfFunctionPointersWithContext &); |
nexpaq | 0:6c56fb4bc5f0 | 268 | CallChainOfFunctionPointersWithContext & operator = (const CallChainOfFunctionPointersWithContext &); |
nexpaq | 0:6c56fb4bc5f0 | 269 | }; |
nexpaq | 0:6c56fb4bc5f0 | 270 | |
nexpaq | 0:6c56fb4bc5f0 | 271 | #endif |