Class: Tb::Cmd::TarReader
- Inherits:
-
Object
- Object
- Tb::Cmd::TarReader
- Defined in:
- lib/tb/cmd_tar.rb
Instance Attribute Summary collapse
-
#offset ⇒ Object
readonly
Returns the value of attribute offset.
Instance Method Summary collapse
-
#calculate_hash(blocklength, filesize, alg_list) ⇒ Object
:yield: alg, result.
- #get_single_record(kind) ⇒ Object
-
#initialize(input) ⇒ TarReader
constructor
A new instance of TarReader.
- #read_exactly(size, kind) ⇒ Object
- #read_single_record(kind) ⇒ Object
- #skip(size, kind) ⇒ Object
Constructor Details
#initialize(input) ⇒ TarReader
Returns a new instance of TarReader.
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# File 'lib/tb/cmd_tar.rb', line 184 def initialize(input) @input = input @offset = 0 end |
Instance Attribute Details
#offset ⇒ Object (readonly)
Returns the value of attribute offset.
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# File 'lib/tb/cmd_tar.rb', line 188 def offset @offset end |
Instance Method Details
#calculate_hash(blocklength, filesize, alg_list) ⇒ Object
:yield: alg, result
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# File 'lib/tb/cmd_tar.rb', line 248 def calculate_hash(blocklength, filesize, alg_list) # :yield: alg, result digests = {} alg_list.each {|alg| c = Digest.const_get(Tb::Cmd::TAR_HASH_ALGORITHMS.fetch(alg)) digests[alg] = c.new } rest = blocklength while 0 < rest if rest < 4096 s = rest else s = 4096 end ret = @input.read(s) if !ret || ret.length != s warn "premature end of tar archive content (#{kind})" raise Tb::Cmd::TarFormatError end if filesize < s ret = ret[0, filesize] end digests.each {|alg, d| d.update ret } filesize -= s rest -= s end @offset += blocklength result = {} digests.each {|alg, d| result[alg] = d.hexdigest } result end |
#get_single_record(kind) ⇒ Object
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# File 'lib/tb/cmd_tar.rb', line 190 def get_single_record(kind) record = @input.read(Tb::Cmd::TAR_RECORD_LENGTH) if !record return nil end if record.length != Tb::Cmd::TAR_RECORD_LENGTH warn "premature end of tar archive (#{kind})" raise Tb::Cmd::TarFormatError end @offset += Tb::Cmd::TAR_RECORD_LENGTH record end |
#read_exactly(size, kind) ⇒ Object
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# File 'lib/tb/cmd_tar.rb', line 212 def read_exactly(size, kind) record = @input.read(size) if !record warn "premature end of tar archive (#{kind})" raise Tb::Cmd::TarFormatError end if record.length != size warn "premature end of tar archive (#{kind})" raise Tb::Cmd::TarFormatError end @offset += size record end |
#read_single_record(kind) ⇒ Object
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# File 'lib/tb/cmd_tar.rb', line 203 def read_single_record(kind) record = get_single_record(kind) if !record warn "premature end of tar archive (#{kind})" raise Tb::Cmd::TarFormatError end record end |
#skip(size, kind) ⇒ Object
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# File 'lib/tb/cmd_tar.rb', line 226 def skip(size, kind) begin @input.seek(size, IO::SEEK_CUR) rescue Errno::ESPIPE rest = size while 0 < rest if rest < 4096 s = rest else s = 4096 end ret = @input.read(s) if !ret || ret.length != s warn "premature end of tar archive content (#{kind})" raise Tb::Cmd::TarFormatError end rest -= s end end @offset += size end |