52 lines
943 B
Ruby
52 lines
943 B
Ruby
# Class CircularBuffer
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class CircularBuffer
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class BufferEmptyException < RuntimeError
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end
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class BufferFullException < RuntimeError
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end
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def initialize(buffer_size)
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@buffer = Array.new(buffer_size)
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end
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def read
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raise BufferEmptyException if @front.nil?
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value = @buffer[@front]
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@buffer[@front] = nil
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if @front == @back
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@back = @front = nil
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else
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@front = next_index(@front)
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end
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value
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end
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def write(data, force = false)
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raise BufferFullException if @buffer[next_index(@back)] && !force
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@back = next_index(@back)
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@front = 0 if @front.nil?
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@buffer[@back] = data
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end
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def write!(data)
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@front = next_index(@front) if @buffer[next_index(@front)]
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write(data, true)
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end
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def clear
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@buffer = Array.new(@buffer.size)
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@front = @back = nil
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end
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private
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def next_index(index)
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return 0 if index.nil?
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(index + 1) % @buffer.size
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end
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end
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