Class: Archive::Tar::Minitar::Reader
- Inherits:
-
Object
- Object
- Archive::Tar::Minitar::Reader
- Defined in:
- lib/archive/tar/minitar/reader.rb
Overview
The class that reads a tar format archive from a data stream. The data stream may be sequential or random access, but certain features only work with random access data streams.
Defined Under Namespace
Modules: InvalidEntryStream Classes: EntryStream
Class Method Summary collapse
-
.each_entry(io) ⇒ Object
Iterates over each entry in the provided input.
-
.open(io) ⇒ Object
With no associated block,
Reader::open
is a synonym forReader::new
.
Instance Method Summary collapse
- #close ⇒ Object
-
#closed? ⇒ Boolean
Returns false if the reader is open (it never closes).
-
#each_entry ⇒ Object
(also: #each)
Iterates through each entry in the data stream.
-
#initialize(io) ⇒ Reader
constructor
Creates and returns a new Reader object.
-
#rewind ⇒ Object
Resets the read pointer to the beginning of data stream.
Constructor Details
#initialize(io) ⇒ Reader
Creates and returns a new Reader object.
180 181 182 183 |
# File 'lib/archive/tar/minitar/reader.rb', line 180 def initialize(io) @io = io @init_pos = io.pos end |
Class Method Details
.each_entry(io) ⇒ Object
Iterates over each entry in the provided input. This wraps the common pattern of:
Archive::Tar::Minitar::Input.open(io) do |i|
inp.each do |entry|
# ...
end
end
If a block is not provided, an enumerator will be created with the same behaviour.
call-seq:
Archive::Tar::Minitar::Reader.each_entry(io) -> enumerator
Archive::Tar::Minitar::Reader.each_entry(io) { |entry| block } -> obj
169 170 171 172 173 174 175 176 177 |
# File 'lib/archive/tar/minitar/reader.rb', line 169 def self.each_entry(io) return to_enum(__method__, io) unless block_given? open(io) do |reader| reader.each_entry do |entry| yield entry end end end |
.open(io) ⇒ Object
With no associated block, Reader::open
is a synonym for Reader::new
. If the optional code block is given, it will be passed the new writer as an argument and the Reader object will automatically be closed when the block terminates. In this instance, Reader::open
returns the value of the block.
141 142 143 144 145 146 147 148 149 150 151 152 |
# File 'lib/archive/tar/minitar/reader.rb', line 141 def self.open(io) reader = new(io) return reader unless block_given? # This exception context must remain, otherwise the stream closes on open # even if a block is not given. begin yield reader ensure reader.close end end |
Instance Method Details
#close ⇒ Object
250 251 |
# File 'lib/archive/tar/minitar/reader.rb', line 250 def close end |
#closed? ⇒ Boolean
Returns false if the reader is open (it never closes).
246 247 248 |
# File 'lib/archive/tar/minitar/reader.rb', line 246 def closed? false end |
#each_entry ⇒ Object Also known as: each
Iterates through each entry in the data stream.
203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 |
# File 'lib/archive/tar/minitar/reader.rb', line 203 def each_entry return to_enum unless block_given? loop do return if @io.eof? header = Archive::Tar::Minitar::PosixHeader.from_stream(@io) return if header.empty? if header.long_name? name = @io.read(512).rstrip header = PosixHeader.from_stream(@io) return if header.empty? header.name = name end entry = EntryStream.new(header, @io) size = entry.size yield entry skip = (512 - (size % 512)) % 512 if Archive::Tar::Minitar.seekable?(@io, :seek) # avoid reading... @io.seek(size - entry.bytes_read, IO::SEEK_CUR) else pending = size - entry.bytes_read while pending > 0 bread = @io.read([pending, 4096].min).size raise UnexpectedEOF if @io.eof? pending -= bread end end @io.read(skip) # discard trailing zeros # make sure nobody can use #read, #getc or #rewind anymore entry.close end end |
#rewind ⇒ Object
Resets the read pointer to the beginning of data stream. Do not call this during a #each or #each_entry iteration. This only works with random access data streams that respond to #rewind and #pos.
188 189 190 191 192 193 194 195 196 197 198 199 200 |
# File 'lib/archive/tar/minitar/reader.rb', line 188 def rewind if @init_pos.zero? unless Archive::Tar::Minitar.seekable?(@io, :rewind) raise Archive::Tar::Minitar::NonSeekableStream end @io.rewind else unless Archive::Tar::Minitar.seekable?(@io, :pos=) raise Archive::Tar::Minitar::NonSeekableStream end @io.pos = @init_pos end end |