--- /dev/null
+#include "WindowedFifo.h"\r
+\r
+/**\r
+ *\r
+ */\r
+WindowedFifo::WindowedFifo(char* name, unsigned size = 20) {\r
+ //std::cout << "Create WindowedFifo." << std::endl;\r
+ _size = size;\r
+ _buffer = new char[_size];\r
+ _head = 0;\r
+ _tail = 0;\r
+ _headRoom = 0;\r
+ _tailRoom = 0;\r
+ _use = 0;\r
+ //indicates whether Fifo is empty or full if _head == _tail\r
+ //_isFull = false;\r
+ _isHeadReserved = false;\r
+ _isTailReserved = false;\r
+ _name = new char[strlen(name) + 1];\r
+ strcpy(_name, name);\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+WindowedFifo::~WindowedFifo() {\r
+ //std::cout << "Delete WindowedFifo." << std::endl;\r
+ if (_buffer) {\r
+ delete _buffer;\r
+ }\r
+ if (_name) {\r
+ delete _name;\r
+ }\r
+ _buffer = 0;\r
+ _head = 0;\r
+ _tail = 0;\r
+ _name = 0;\r
+ _use = 0;\r
+ //std::cout << "Deleted WindowedFifo." << std::endl;\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+unsigned WindowedFifo::reserve(void** dest, unsigned len) {\r
+ char** destination = (char**)dest;\r
+ //std::cout << "Attempt to reserve " << len << " bytes." << std::endl;\r
+\r
+ //can only reserve once piece at a time\r
+ if (_isHeadReserved) {\r
+ *destination = 0;\r
+ return 0;\r
+ }\r
+\r
+ while (unused() == 0) {\r
+ wait(_readEvent);\r
+ }\r
+\r
+ //reserve at most as much memory as still available in the buffer\r
+ unsigned write = (len <= _size - _use ? len : _size - _use);\r
+\r
+ if (write > 0) {\r
+ //if wrap-around in buffer: return only buffer for the\r
+ //contiguous buffer space\r
+ if (_head + write > _size) {\r
+ write = _size - _head;\r
+ }\r
+\r
+ _headRoom = (_head + write) == _size? 0 : _head + write;\r
+ *destination = &(_buffer[_head]);\r
+ _isHeadReserved = true;\r
+\r
+ //the following comparison is unsafe in a multi-threaded\r
+ //environment and potentially leads to race-conditions\r
+ /*if (_headRoom == _tail) {\r
+ _isFull = true;\r
+ } else {\r
+ _isFull = false;\r
+ }*/\r
+ }\r
+\r
+ //std::cout << "Reserved " << write << " bytes." << std::endl;\r
+ _writeReserve = write; \r
+ return write;\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+void WindowedFifo::release() {\r
+ if (_isHeadReserved) {\r
+ //std::cout << "Released " << _headRoom - _head << " bytes." << std::endl;\r
+ _head = _headRoom;\r
+ _use += _writeReserve;\r
+ _isHeadReserved = false;\r
+ _writeEvent.notify();\r
+ }\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+unsigned WindowedFifo::capture(void **dest, unsigned len) {\r
+ char** destination = (char**)dest;\r
+ //std::cout << "Attempt to capture " << len << " bytes." << std::endl;\r
+\r
+ if (_isTailReserved) {\r
+ //std::cout << "Only one attempt to capture allowed." << std::endl;\r
+ *destination = 0;\r
+ return 0;\r
+ }\r
+\r
+ while (used() == 0) {\r
+ wait(_writeEvent);\r
+ }\r
+\r
+ //capture at most as much data as available in the buffer\r
+ unsigned read = (len <= _use ? len : _use);\r
+\r
+ if ( read > 0 ) {\r
+ //if wrap-around in buffer: return only buffer for the\r
+ //contiguous buffer space\r
+ if (_tail + read> _size) {\r
+ read = _size - _tail;\r
+ }\r
+\r
+ _tailRoom = (_tail + read) == _size ? 0 : _tailRoom = _tail + read;\r
+ *destination = &(_buffer[_tail]);\r
+ _isTailReserved = true;\r
+ }\r
+\r
+ //std::cout << "Captured " << read << " bytes." << std::endl;\r
+\r
+ _readReserve = read; \r
+ return read;\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+void WindowedFifo::consume() {\r
+ if (_isTailReserved) {\r
+ //std::cout << "Consumed " << _tailRoom - _tail << " bytes." << std::endl;\r
+ _tail = _tailRoom;\r
+ _use -= _readReserve;\r
+ _isTailReserved = false;\r
+ //_isFull = false;\r
+ _readEvent.notify();\r
+ }\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+unsigned WindowedFifo::size() const {\r
+ return _size;\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+unsigned WindowedFifo::unused() const {\r
+ return _size - _use;\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+unsigned WindowedFifo::used() const {\r
+ return _use;\r
+ /*if (_headRoom > _tail) {\r
+ return _headRoom - _tail;\r
+ } else if (_headRoom == _tail) {\r
+ if (_isFull == true) {\r
+ return _size;\r
+ } else {\r
+ return 0;\r
+ }\r
+ }\r
+ return _headRoom + _size - _tail;*/\r
+}\r
+\r
+/**\r
+ *\r
+ */\r
+char* WindowedFifo::getName() const {\r
+ return _name;\r
+}\r
+\r
+/**\r
+ * Test the implementation\r
+ */\r
+/*\r
+#include <iostream>\r
+#include <iomanip>\r
+#define LENGTH 10\r
+\r
+class producer : public sc_module\r
+{\r
+ public:\r
+ WindowedFifo *wfifo;\r
+\r
+ SC_HAS_PROCESS(producer);\r
+\r
+ producer(sc_module_name name) : sc_module(name)\r
+ {\r
+ SC_THREAD(main);\r
+ }\r
+\r
+ void main()\r
+ {\r
+ for (int j = 0; j < LENGTH; j++) {\r
+ //std::cout << "write " << i << " to Fifo. ";\r
+ int *buf1;\r
+ int write = wfifo->reserve((void**)&buf1, sizeof(int));\r
+\r
+ if (write == sizeof(int)) {\r
+ *buf1 = j;\r
+ wfifo->release();\r
+ //std::cout << "used: " << std::setw(2) << wfifo->used()\r
+ // << ", unused: " << std::setw(2) << wfifo->unused()\r
+ // << ", size: " << std::setw(2) << wfifo->size()\r
+ // << std::endl;\r
+ } else {\r
+ std::cout << "Not successful: " << write << std::endl;\r
+ }\r
+ }\r
+ printf("producer returns.\n");\r
+ }\r
+};\r
+\r
+class consumer : public sc_module\r
+{\r
+ public:\r
+ WindowedFifo *wfifo;\r
+\r
+ SC_HAS_PROCESS(consumer);\r
+\r
+ consumer(sc_module_name name) : sc_module(name)\r
+ {\r
+ SC_THREAD(main);\r
+ }\r
+\r
+ void main()\r
+ {\r
+ for (int j = 0; j < LENGTH; j++) {\r
+ int* buf3;\r
+ int read = wfifo->capture((void**)&buf3, sizeof(int));\r
+ if (read == sizeof(int)) {\r
+ std::cout << "read " << (unsigned)*buf3 << " from WindowedFifo ";\r
+ std::cout << "used: " << std::setw(2) << wfifo->used()\r
+ << ", unused: " << std::setw(2) << wfifo->unused()\r
+ << ", size: " << std::setw(2) << wfifo->size()\r
+ << std::endl;\r
+ wfifo->consume();\r
+ } else {\r
+ std::cout << "Read nothing from WindowedFifo." << std::endl;\r
+ }\r
+ }\r
+ printf("consumer returns.\n");\r
+ }\r
+};\r
+\r
+class top : public sc_module\r
+{\r
+ public:\r
+ WindowedFifo *wfifo_inst;\r
+ producer *prod_inst;\r
+ consumer *cons_inst;\r
+\r
+ top(sc_module_name name) : sc_module(name)\r
+ {\r
+ wfifo_inst = new WindowedFifo("myfifo", 4);\r
+\r
+ prod_inst = new producer("producer");\r
+ prod_inst->wfifo = wfifo_inst;\r
+\r
+ cons_inst = new consumer("consumer");\r
+ cons_inst->wfifo = wfifo_inst;\r
+ }\r
+};\r
+\r
+int sc_main (int argc , char *argv[]) {\r
+ top top1("top");\r
+ sc_start();\r
+ return 0;\r
+}\r
+*/\r
projects / jump.git / blobdiff