xar unarchiver (.xar, .pkg, .xip)
implement bzip2 reader
+53
+53
bzip2.cr
+53
bzip2.cr
···
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require "./memfile"
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@[Link("bzip2")]
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lib LibBzip2
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alias BZFILE = Void
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fun BZ2_bzReadOpen(bzerror : Pointer(Int32), f : Pointer(Void), verbosity : Int32, small : Int32, unused : Pointer(Void), nUnused : Int32) : Pointer(BZFILE)
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fun BZ2_bzRead(bzerror : Pointer(Int32), b : Pointer(BZFILE), buf : Pointer(UInt8), len : Int32) : Int32
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fun BZ2_bzReadClose(bzerror : Pointer(Int32), b : Pointer(BZFILE)) : Void
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end
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class Bzip2::Reader
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@io : IO
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@bzfile : Pointer(LibBzip2::BZFILE)
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@bzerror : Pointer(Int32)
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@file_ptr : Pointer(Void) # MemFile pointer
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def initialize(io : IO)
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@io = io
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# Create a memory-backed FILE* pointer from IO
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@file_ptr = MemFile.from_io(io)
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raise "Could not map memfile" unless @file_ptr
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@bzerror = Pointer(Int32).malloc(1)
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@bzfile = LibBzip2.BZ2_bzReadOpen(@bzerror, @file_ptr, 0, 0, Pointer(Void).null, 0)
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raise "Failed to open Bzip2 stream, error=#{@bzerror.value}" unless @bzfile
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end
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def getb_to_end : Bytes
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result = Bytes.new(0)
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buffer = Bytes.new(4096)
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while true
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bytes_read = LibBzip2.BZ2_bzRead(@bzerror, @bzfile, buffer.to_unsafe, buffer.size)
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case @bzerror.value
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when 0 # BZ_OK
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result += buffer[0, bytes_read]
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when 4 # BZ_STREAM_END
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result += buffer[0, bytes_read] if bytes_read > 0
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break
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else
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raise "BZ2_bzRead failed with error #{@bzerror.value}"
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end
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end
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result
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end
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def finalize
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LibBzip2.BZ2_bzReadClose(@bzerror, @bzfile)
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end
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end