unix: add GetsockoptString for Darwin, *BSD and Solaris
As suggested by Brad in CL 83275.
From what I can tell getsockopt syscall on these OSes doesn't return
ERANGE in any case, so these versions don't include the buffer growing.
Change-Id: I667c3751021e26defec0a04761a689fa4b78c65d
Reviewed-on: https://go-review.googlesource.com/84016
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/unix/syscall_bsd.go b/unix/syscall_bsd.go
index 47b0598..d3903ed 100644
--- a/unix/syscall_bsd.go
+++ b/unix/syscall_bsd.go
@@ -352,6 +352,18 @@
return &value, err
}
+// GetsockoptString returns the string value of the socket option opt for the
+// socket associated with fd at the given socket level.
+func GetsockoptString(fd, level, opt int) (string, error) {
+ buf := make([]byte, 256)
+ vallen := _Socklen(len(buf))
+ err := getsockopt(fd, level, opt, unsafe.Pointer(&buf[0]), &vallen)
+ if err != nil {
+ return "", err
+ }
+ return string(buf[:vallen-1]), nil
+}
+
//sys recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
//sys sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
//sys recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
