// POSIX socket module (macOS only)
// sockaddr_in layout and constants are platform-specific.

libc :: #library "c";

// POSIX socket API
socket     :: (domain: s32, kind: s32, protocol: s32) -> s32 #foreign libc;
setsockopt :: (fd: s32, level: s32, optname: s32, optval: *s32, optlen: u32) -> s32 #foreign libc;
bind       :: (fd: s32, addr: *SockAddr, addrlen: u32) -> s32 #foreign libc;
listen     :: (fd: s32, backlog: s32) -> s32 #foreign libc;
accept     :: (fd: s32, addr: *SockAddr, addrlen: *u32) -> s32 #foreign libc;
read       :: (fd: s32, buf: [*]u8, count: s64) -> s64 #foreign libc;
write      :: (fd: s32, buf: [*]u8, count: s64) -> s64 #foreign libc;
close      :: (fd: s32) -> s32 #foreign libc;

// Constants (macOS)
AF_INET      :s32: 2;
SOCK_STREAM  :s32: 1;
SOL_SOCKET   :s32: 0xFFFF;
SO_REUSEADDR :s32: 0x4;

// macOS sockaddr_in (16 bytes, has sin_len field)
SockAddr :: struct {
    sin_len:    u8;
    sin_family: u8;
    sin_port:   u16;
    sin_addr:   u32 = 0;
    sin_zero:   u64 = 0;
}

htons :: (port: s64) -> u16 {
    cast(u16) (((port & 0xFF) << 8) | ((port >> 8) & 0xFF));
}