Rename SO_{RCV,SND}TIMEO for Linux 5.1

[J0WI]

ponyc/src/libponyrt/lang/socket.c

Lines 4473 to 4474 in 2bf65c0

	#ifdef SO_RCVTIMEO
	case 887: return SO_RCVTIMEO;

ponyc/src/libponyrt/lang/socket.c

Lines 4530 to 4531 in 2bf65c0

	#ifdef SO_SNDTIMEO
	case 906: return SO_SNDTIMEO;

They have been renamed in Linux 5.1.

[slfritchie]

Hi, @J0WI, thanks for opening this ticket; I didn't know that this renaming is happening in the Linux kernel.

If you (or anyone else) has the need to use these constants, with the _OLD or _NEW suffix, it would be straightforward to add them. A PR with that patch would be nice, but not strictly necessary if you need something to work right now.

At the moment, it looks like UDP_VENDOR is the last #ifdef in

ponyc/src/libponyrt/lang/socket.c

Lines 5103 to 5104 in 2bf65c0

	#ifdef UDP_VENDOR
	case 1097: return UDP_VENDOR;

and uses the constant 1097. The _OLD symbols can be added at the end with constants 1098 and 1099. The _NEW symbols can be added also, with constants 1100-1101, assuming of course that the same #ifdef wrappers are used around both old & new constants.

[J0WI]

This will still fail to compile on Linux 5.1+:

In file included from src/libponyrt/lang/socket.c:49:
src/libponyrt/lang/socket.c: In function 'pony_os_sockopt_option':
src/libponyrt/lang/socket.c:4474:22: error: 'SO_RCVTIMEO_OLD' undeclared (first use in this function); did you mean 'SO_RCVTIMEO_NEW'?
 4474 |     case 887: return SO_RCVTIMEO;
      |                      ^~~~~~~~~~~
src/libponyrt/lang/socket.c:4474:22: note: each undeclared identifier is reported only once for each function it appears in
src/libponyrt/lang/socket.c:4531:22: error: 'SO_SNDTIMEO_OLD' undeclared (first use in this function); did you mean 'SO_SNDTIMEO_NEW'?
 4531 |     case 906: return SO_SNDTIMEO;
      |                      ^~~~~~~~~~~
make: *** [Makefile:941: build/release/obj-native/libponyrt/lang/socket.o] Error 1

Renaming them with _OLD works fine for me.

[slfritchie]

Thanks, @J0WI. Could you try the patch at https://gist.github.com/slfritchie/954557a58e1afce558db912356ee3c7a ? That creates the new constants plus the OSSockOpt glue to use them.

use "net"

actor Main
  new create(env: Env) =>
    @printf[I32]("so_rcvtimeo_new = %d\n".cstring(), OSSockOpt.so_rcvtimeo_new())

When I run this on a machine that doesn't have SO_RCVTIMEO_NEW available (like my OS X laptop), the value printed is -1.

[J0WI]

It does not compile, same error as before.