Re: getsockopt(2)

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

christos%astron.com@localhost (Christos Zoulas) wrote:
>In article <x7d135tur5.fsf%ren.fdy2.co.uk@localhost>,
>Robert Swindells  <rjs%fdy2.co.uk@localhost> wrote:
>>
>>What is wrong with your idea of updatesockopt(2) ? Or maybe call it
>>getsockopt2() and only use it for the "get with extra argument" case.
>
>I guess getsockopt2/updatesockopt is not that bad after all. Perhaps
>we should go with that?

This is working for me:

Index: uipc_syscalls.c
===================================================================
RCS file: /cvsroot/src/sys/kern/uipc_syscalls.c,v
retrieving revision 1.191
diff -u -r1.191 uipc_syscalls.c
--- uipc_syscalls.c	12 Feb 2018 16:01:35 -0000	1.191
+++ uipc_syscalls.c	6 Mar 2018 00:47:02 -0000
@@ -1266,6 +1266,68 @@
 	return error;
 }
 
+int
+sys_getsockopt2(struct lwp *l, const struct sys_getsockopt2_args *uap,
+    register_t *retval)
+{
+	/* {
+		syscallarg(int)			s;
+		syscallarg(int)			level;
+		syscallarg(int)			name;
+		syscallarg(void *)		val;
+		syscallarg(unsigned int *)	avalsize;
+	} */
+	struct sockopt	sopt;
+	struct socket	*so;
+	file_t		*fp;
+	unsigned int	valsize, len;
+	int		error;
+
+	if (SCARG(uap, val) != NULL) {
+		error = copyin(SCARG(uap, avalsize), &valsize, sizeof(valsize));
+		if (error)
+			return error;
+	} else
+		valsize = 0;
+
+	if (valsize > MCLBYTES)
+		return EINVAL;
+
+	if ((error = fd_getsock1(SCARG(uap, s), &so, &fp)) != 0)
+		return (error);
+
+	sockopt_init(&sopt, SCARG(uap, level), SCARG(uap, name), valsize);
+	if (valsize > 0) {
+		error = copyin(SCARG(uap, val), sopt.sopt_data, valsize);
+		if (error)
+			goto out;
+	}
+
+	if (fp->f_flag & FNOSIGPIPE)
+		so->so_options |= SO_NOSIGPIPE;
+	else
+		so->so_options &= ~SO_NOSIGPIPE;
+	error = sogetopt(so, &sopt);
+	if (error)
+		goto out;
+
+	if (valsize > 0) {
+		len = min(valsize, sopt.sopt_size);
+		error = copyout(sopt.sopt_data, SCARG(uap, val), len);
+		if (error)
+			goto out;
+
+		error = copyout(&len, SCARG(uap, avalsize), sizeof(len));
+		if (error)
+			goto out;
+	}
+
+ out:
+	sockopt_destroy(&sopt);
+	fd_putfile(SCARG(uap, s));
+	return error;
+}
+
 #ifdef PIPE_SOCKETPAIR
 
 int
Index: syscalls.master
===================================================================
RCS file: /cvsroot/src/sys/kern/syscalls.master,v
retrieving revision 1.291
diff -u -r1.291 syscalls.master
--- syscalls.master	6 Jan 2018 16:41:23 -0000	1.291
+++ syscalls.master	6 Mar 2018 00:47:03 -0000
@@ -986,3 +986,5 @@
 			    siginfo_t *info); }
 482	STD		{ int|sys||clock_getcpuclockid2(idtype_t idtype, \
 			    id_t id, clockid_t *clock_id); }
+483	STD	RUMP	{ int|sys||getsockopt2(int s, int level, int name, \
+			    void *val, socklen_t *avalsize); }