Can you create a circular buffer in C?
We will start with a C implementation, as this exposes us to some of the design challenges and tradeoffs when creating a circular buffer library. Since we are creating a circular buffer library, we want to make sure users work with our library APIs instead of modifying the structure directly.
What kind of data structure is a circular buffer?
A circular buffer is a data structure that uses a fixed-size buffer as if it were connected end-to-end (in a circle). We’re going to be using an array of integers for this guide.
How are circular buffers used in embedded systems?
Due to the resource constrained nature of embedded systems, circular buffer data structures can be found in most projects. Circular buffers (also known as ring buffers) are fixed-size buffers that work as if the memory is contiguous & circular in nature.
How is the buffer length stored in C?
A good way to store this information is in a constant. Next, we’ll need a variable to store the buffer length. The buffer length is the current number of filled elements (elements we’ve written to). Each time we write a new value, we’ll increment the buffer length by 1.
What happens when two elements are removed from a circular buffer?
If two elements are removed, the two oldest values inside of the Circular Buffer would be removed. Circular Buffers use FIFO (First In, First Out) logic. In the example 1 & 2 were the first to enter the Circular Buffer, they are the first to be removed, leaving 3 inside of the Buffer. If the buffer has 7 elements, then it is completely full:
How is a circular buffer different from a linear buffer?
However, since memory is never physically created as a ring, a linear representation is generally used as is done below. A circular buffer, circular queue, cyclic buffer or ring buffer is a data structure that uses a single, fixed-size buffer as if it were connected end-to-end.