Files
netlinkrb/lib/linux/sendmsg.rb
2011-05-16 11:29:07 +01:00

91 lines
2.5 KiB
Ruby

# Patchup to add Socket#sendmsg and Socket#recvmsg for ruby 1.8
if BasicSocket.instance_methods.grep(/^sendmsg$/).empty?
begin
require 'ffi'
rescue LoadError
require('rubygems') ? retry : raise
end
class BasicSocket
module FFIExt
extend FFI::Library
ffi_lib FFI::Library::LIBC
attach_function :sendmsg, [:int, :buffer_in, :int], :ssize_t
attach_function :recvmsg, [:int, :buffer_inout, :int], :ssize_t
end
class Msghdr < FFI::Struct
layout :name, :pointer,
:namelen, :socklen_t,
:iov, :pointer,
:iovlen, :size_t,
:control, :pointer,
:controllen, :socklen_t,
:flags, :int
end
class IOVec < FFI::Struct
layout :base, :pointer,
:len, :size_t
end
def sendmsg(mesg, flags=0, dest_sockaddr=nil, *controls)
data = FFI::MemoryPointer.new(mesg.bytesize, 1, false)
data.put_bytes(0, mesg)
iov = IOVec.new
iov[:base] = data
iov[:len] = mesg.bytesize
header = Msghdr.new
if dest_sockaddr
dest_sockaddr = dest_sockaddr.to_sockaddr if dest_sockaddr.respond_to?(:to_sockaddr)
nbuf = FFI::MemoryPointer.new(dest_sockaddr.bytesize, 1, false)
nbuf.put_bytes(0, dest_sockaddr)
header[:name] = nbuf
header[:namelen] = dest_sockaddr.bytesize
end
header[:iov] = iov
header[:iovlen] = 1
header[:control] = nil # TODO: controls
header[:controllen] = 0 # controls
header[:flags] = flags
Kernel.select(nil, [self])
res = FFIExt.sendmsg(fileno, header, flags)
raise "sendmsg error: #{res}" if res < 0 # FIXME: read errno
# return numbytes_sent
res
end
def recvmsg(maxmesglen=nil, flags=0, maxcontrollen=nil, opts={})
data = FFI::MemoryPointer.new(maxmesglen || 4096, 1, false)
namebuf = FFI::MemoryPointer.new(64, 1, false)
iov = IOVec.new
iov[:base] = data
iov[:len] = data.size
header = Msghdr.new
header[:name] = namebuf
header[:namelen] = namebuf.size
header[:iov] = iov
header[:iovlen] = 1
header[:flags] = flags
Kernel.select([self])
res = FFIExt.recvmsg(fileno, header, flags)
raise "recvmsg error: #{res}" if res < 0 # FIXME: read errno
# return [mesg, sender_addrinfo, rflags, *controls]
return [
data.get_bytes(0, res),
namebuf.get_bytes(0, header[:namelen]),
header[:flags]
# TODO: controls
]
end
end
end