Class: RStyx::Server::SDirectory

Inherits:
SFile
  • Object
show all
Defined in:
lib/rstyx/server.rb

Overview

Class representing a directory on the Styx server.

Direct Known Subclasses

DirectoryOnDisk

Instance Attribute Summary

Attributes inherited from SFile

#atime, #gid, #mtime, #muid, #name, #parent, #permissions, #uid, #version

Instance Method Summary collapse

Methods inherited from SFile

#add_changelistener, #add_client, #appendonly?, #auth?, #can_setlength?, #can_setmode?, #can_setmtime?, #can_setname?, #client, #client_connected, #client_disconnected, #contents_changed, #delete, #directory?, #exclusive?, #filetype, #full_path, #length, #length=, #mode, #mode=, #num_clients, #qid, #refresh, #remove, #remove_client, #remove_dead_clients, #rename, #reply_read, #reply_write, #set_mtime, #stat, #uuid, #version_incr, #write

Constructor Details

#initialize(name, argv = { :permissions => 0777, :uid => ENV["USER"], :gid => ENV["GROUP"], :filemaker => nil }) ⇒ SDirectory

Create a new directory with name name. Permissions are obtained from the argv hash as with SFile. The default permissions are 0777 though. In addition to the usual file arguments in argv, SDirectory instances also recognize a :filemaker key which specifies a block that may be called whenever a file is created. The block receives as parameters the SDirectory instance, the name of the file to create, and the permissions of the file. It should return an SFile subclass instance, which becomes the new file on success, or raise a StyxException if there is some problem.



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# File 'lib/rstyx/server.rb', line 1692

def initialize(name, argv={ :permissions => 0777, :uid => ENV["USER"],
                 :gid => ENV["GROUP"], :filemaker => nil })
  # directories cannot be append-only, exclusive, or auth files
  argv.merge({:apponly => false, :excl => false})
  super(name, argv)
  @directory = true
  @children = []
  @children.extend(MonitorMixin)
  @filemaker = argv[:filemaker]
end

Instance Method Details

#<<(child) ⇒ Object

Add an SFile child to this directory. If a file with the same name already exists, throws a FileExists exception.



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# File 'lib/rstyx/server.rb', line 1718

def <<(child)
  @children.synchronize do
    if child_exists?(child.name)
      raise FileExists("#{sf.name} already exists")
    end
    child.parent = self
    @children << child
  end
  return(child)
end

#[](name) ⇒ Object

Get the child with the name name, or nil if no such file is present in this directory.



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# File 'lib/rstyx/server.rb', line 1733

def [](name)
  if name == "."
    return(self)
  end
  if name == ".."
    return(self.parent)
  end
  @children.synchronize do
    @children.each do |c|
      if c.name == name
        return(c)
      end
    end
    return(nil)
  end
end

#child_count ⇒ Object

Get the number of children this directory has



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# File 'lib/rstyx/server.rb', line 1753

def child_count
  return(@children.length)
end

#child_exists?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rstyx/server.rb', line 1703

def child_exists?(name)
  @children.synchronize do
    @children.each do |c|
      if c.name == name
        return(true)
      end
    end
    return(false)
  end
end

#newfile(name, perm, isdir, isapponly, isexcl) ⇒ Object

Create a new file with name name and permissions perm in this directory. – FIXME: make this method actually DO something! ++

Raises:



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# File 'lib/rstyx/server.rb', line 1808

def newfile(name, perm, isdir, isapponly, isexcl)
  raise StyxException.new("cannot create files in this directory")
end

#read(client, offset, count) ⇒ Object

Read the contents of the directory.

client

the SFileClient object representing the client reading from this directory.

offset

the offset the client wants to read from. Nonzero offsets are only valid if the client has read from the directory before, and may only be the values obtained from a previous read.

count

the number of bytes that the client wishes to read. The read will always return the nearest integral number of directory entries whose length is less than the count (i.e. if five entries take 300 bytes and the sixth entry takes 40 bytes, and count was set to 320, only five entries and 300 bytes will be returned).



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# File 'lib/rstyx/server.rb', line 1774

def read(client, offset, count)
  # Check that the offset is valid; zero offsets are always valid,
  # but non-zero offsets are only valid if this client has read part
  # of the contents of the directory before.
  if (offset != 0 && offset != client.offset)
    raise StyxException.new("invalid offset when reading directory")
  end

  # Create a string to store the serialized stat representations
  # of the directory's contents.
  str = ""
  nextfile = (offset == 0) ? 0 : client.next_file_to_read
  while (nextfile < @children.length)
    sf = @children[nextfile]
    s = sf.stat.to_bytes
    if (s.length + str.length) > count
      break
    end
    # Add the serialized stat to the buffer
    str << s
    nextfile += 1
  end
  client.next_file_to_read = nextfile
  client.offset += str.length
  return(reply_read(str))
end

#remove_child(child) ⇒ Object

Remove a file from the directory



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# File 'lib/rstyx/server.rb', line 1814

def remove_child(child)
  @children.delete(child)
  self.contents_changed
end