On 19/03/20 18:38, Guy Harris wrote:
On Mar 19, 2020, at 7:40 AM, Gisle Vanem <gisle.vanem@xxxxxxxxx> wrote:
I'm surprised no one has come across this compile
error yet:
epan/dissectors/packet-f5ethtrailer.c(482): error C2143: syntax error: missing ';' before '.'
epan/dissectors/packet-f5ethtrailer.c(485): error C2224: left of '.S_addr' must have struct/union type
epan/dissectors/packet-f5ethtrailer.c(487): error C2224: left of '.S_addr' must have struct/union type
(using MSVC-2019).
Reason seems simple; <winsock2.h> has snuck in somehow and
added the wellknown "#define s_addr S_un.S_addr"
This isn't unique to Windows. It dates back to old BSD, in which struct in_addr contained a union of multiple different types for an IP address, with some types being structures breaking up the address into host and network bits, and even included bits for IMP numbers. s_addr was defined to be the member of the union that just defined an address as a 32-bit integer, so if you referred to the s_addr "field" of the structure it gave you the 32-bit integer value.
Because POSIX defines struct in_addr as an opaque structure with an
s_addr element, some BSD Socket implementations get creative with the
use of unions and use a macro definition for "s_addr", which is terribly
bad practice and a tremendously ugly botch.
