class

CrImage::DecompressionGuard::TrackingIO

Inherits IO / Reference / Object

Convenience method to wrap IO with decompression tracking Returns a wrapper IO that tracks bytes read

Constructors

new(io : IO, guard : Guard, is_compressed : Bool = true)
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Instance methods

close

Forward other IO methods to underlying IO

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closed?

Returns true if this IO is closed.

IO defines returns false, but including types may override.

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flush

Flushes buffered data, if any.

IO defines this is a no-op method, but including types may override.

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read(slice : Bytes) : Int32

Reads at most slice.size bytes from this IO into slice. Returns the number of bytes read, which is 0 if and only if there is no more data to read (so checking for 0 is the way to detect end of file).

io = IO::Memory.new "hello"
slice = Bytes.new(4)
io.read(slice) # => 4
slice          # => Bytes[104, 101, 108, 108]
io.read(slice) # => 1
slice          # => Bytes[111, 101, 108, 108]
io.read(slice) # => 0
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write(slice : Bytes) : Nil

Writes the contents of slice into this IO.

io = IO::Memory.new
slice = Bytes.new(4) { |i| ('a'.ord + i).to_u8 }
io.write(slice)
io.to_s # => "abcd"
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