header

# File lib/rubygems/package/tar_test_case.rb, line 75
  def header(type, fname, dname, length, mode, mtime, checksum = nil, linkname = "")
    checksum ||= " " * 8

    arr = [                  # struct tarfile_entry_posix
      ASCIIZ(fname, 100),    # char name[100];     ASCII + (Z unless filled)
      Z(to_oct(mode, 7)),    # char mode[8];       0 padded, octal null
      Z(to_oct(0, 7)),       # char uid[8];        ditto
      Z(to_oct(0, 7)),       # char gid[8];        ditto
      Z(to_oct(length, 11)), # char size[12];      0 padded, octal, null
      Z(to_oct(mtime, 11)),  # char mtime[12];     0 padded, octal, null
      checksum,              # char checksum[8];   0 padded, octal, null, space
      type,                  # char typeflag[1];   file: "0"  dir: "5"
      ASCIIZ(linkname, 100), # char linkname[100]; ASCII + (Z unless filled)
      "ustar\00"",             # char magic[6];      "ustar\0"
      "00",                  # char version[2];    "00"
      ASCIIZ("wheel", 32),   # char uname[32];     ASCIIZ
      ASCIIZ("wheel", 32),   # char gname[32];     ASCIIZ
      Z(to_oct(0, 7)),       # char devmajor[8];   0 padded, octal, null
      Z(to_oct(0, 7)),       # char devminor[8];   0 padded, octal, null
      ASCIIZ(dname, 155)     # char prefix[155];   ASCII + (Z unless filled)
    ]

    format = "C100C8C8C8C12C12C8CC100C6C2C32C32C8C8C155"
    h = if RUBY_VERSION >= "1.9" then
          arr.join
        else
          arr = arr.join("").split(//).map{|x| x[0]}
          arr.pack format
        end
    ret = h + "\00"" * (512 - h.size)
    assert_equal(512, ret.size)
    ret
  end