diff --git a/nrf5/sdk/ringbuffer.h b/nrf5/sdk/ringbuffer.h new file mode 100644 index 0000000000..3f54a6200c --- /dev/null +++ b/nrf5/sdk/ringbuffer.h @@ -0,0 +1,99 @@ +/* The MIT License (MIT) + * + * Copyright (c) 2013 Philip Thrasher + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * Philip Thrasher's Crazy Awesome Ring Buffer Macros! + * + * Below you will find some naughty macros for easy owning and manipulating + * generic ring buffers. Yes, they are slightly evil in readability, but they + * are really fast, and they work great. + * + * Example usage: + * + * #include + * + * // So we can use this in any method, this gives us a typedef + * // named 'intBuffer'. + * ringBuffer_typedef(int, intBuffer); + * + * int main() { + * // Declare vars. + * intBuffer myBuffer; + * + * bufferInit(myBuffer,1024,int); + * + * // We must have the pointer. All of the macros deal with the pointer. + * // (except for init.) + * intBuffer* myBuffer_ptr; + * myBuffer_ptr = &myBuffer; + * + * // Write two values. + * bufferWrite(myBuffer_ptr,37); + * bufferWrite(myBuffer_ptr,72); + * + * // Read a value into a local variable. + * int first; + * bufferRead(myBuffer_ptr,first); + * assert(first == 37); // true + * + * int second; + * bufferRead(myBuffer_ptr,second); + * assert(second == 72); // true + * + * return 0; + * } + * + */ + +#ifndef _ringbuffer_h +#define _ringbuffer_h + +#define ringBuffer_typedef(T, NAME) \ + typedef struct { \ + int size; \ + int start; \ + int end; \ + T* elems; \ + } NAME + +#define bufferInit(BUF, S, T) \ + BUF.size = S+1; \ + BUF.start = 0; \ + BUF.end = 0; \ + BUF.elems = (T*)calloc(BUF.size, sizeof(T)) + + +#define bufferDestroy(BUF) free(BUF->elems) +#define nextStartIndex(BUF) ((BUF->start + 1) % BUF->size) +#define nextEndIndex(BUF) ((BUF->end + 1) % BUF->size) +#define isBufferEmpty(BUF) (BUF->end == BUF->start) +#define isBufferFull(BUF) (nextEndIndex(BUF) == BUF->start) + +#define bufferWrite(BUF, ELEM) \ + BUF->elems[BUF->end] = ELEM; \ + BUF->end = (BUF->end + 1) % BUF->size; \ + if (isBufferEmpty(BUF)) { \ + BUF->start = nextStartIndex(BUF); \ + } + +#define bufferRead(BUF, ELEM) \ + ELEM = BUF->elems[BUF->start]; \ + BUF->start = nextStartIndex(BUF); + +#endif