RingBuffer.h

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#pragma once
 
#include "Vector.h"
#include "stddef.h"
#include "stdint.h"
 
namespace tiny_dlna {
 
class RingBuffer {
 public:
  RingBuffer(int size = 512) {
    max_len = size;
    buffer.resize(size);
  }
 
  // available to read
  int available() { return actual_len; }
 
  int availableToWrite() { return max_len - actual_len; }
 
  // reads a single character and makes it availble on the buffer
  int read() {
    int result = peek();
    if (result > -1) {
      actual_read_pos++;
      actual_len--;
    }
    // wrap to the start
    if (actual_read_pos >= max_len) {
      actual_read_pos = 0;
    }
    return result;
  }
 
  int read(uint8_t *str, int len) {
    for (int j = 0; j < len; j++) {
      int current = read();
      if (current == 0) {
        return j - 1;
      }
      str[j] = current;
    }
    return len;
  }
 
  // peeks the actual character
  int peek() {
    int result = -1;
    if (actual_len > 0) {
      result = buffer[actual_read_pos];
    }
    return result;
  };
 
  size_t write(uint8_t ch) {
    int result = 0;
    if (actual_len < max_len) {
      buffer[actual_write_pos] = ch;
      actual_write_pos++;
      actual_len++;
      if (actual_write_pos >= max_len) {
        actual_write_pos = 0;
      }
    }
    return result;
  }
 
  size_t write(uint8_t *str, int len) {
    for (int j = 0; j < len; j++) {
      int result = write(str[j]);
      if (result == 0) {
        return j;
      }
    }
    return len;
  }
 
  void resize(int size) { buffer.resize(size); }
 
 protected:
  Vector<char> buffer{0};
  int max_len;
  int actual_len = 0;
  int actual_read_pos = 0;
  int actual_write_pos = 0;
};
 
}  // namespace tiny_dlna