In-progress support for POSIX on Linux for sys/socket.

core/sys/posix/sys_socket.odin

@@ -321,17 +321,28 @@ when ODIN_OS == .NetBSD {
 	@(private) LSOCKET :: "socket"
 }
 
-when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS == .OpenBSD {
+when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS == .OpenBSD || ODIN_OS == .Linux {
 
+	when ODIN_OS == .Linux {
+		socklen_t :: distinct c.uint32_t
+	} else {
 		socklen_t :: distinct c.uint
+	}
 
 	_sa_family_t :: distinct c.uint8_t
 
+	when ODIN_OS == .Linux {
+		sockaddr :: struct {
+			sa_family: sa_family_t, /* [PSX] address family */
+			sa_data:   [14]c.char,  /* [PSX] socket address */
+		}
+	} else {
 		sockaddr :: struct {
 			sa_len:    c.uint8_t,   /* total length */
 			sa_family: sa_family_t, /* [PSX] address family */
 			sa_data:   [14]c.char,  /* [PSX] socket address */
 		}
+	}
 
 
 	when ODIN_OS == .OpenBSD {
@@ -339,6 +350,11 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 		_SS_PAD1SIZE :: 6
 		@(private)
 		_SS_PAD2SIZE :: 240
+	} else when ODIN_OS == .Linux {
+		@(private)
+		_SS_SIZE :: 128
+		@(private)
+		_SS_PADSIZE :: _SS_SIZE - size_of(c.uint16_t) - size_of(c.uint64_t)
 	} else {
 		@(private)
 		_SS_MAXSIZE   :: 128
@@ -350,6 +366,23 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 		_SS_PAD2SIZE  :: _SS_MAXSIZE - size_of(c.uint8_t) - size_of(sa_family_t) - _SS_PAD1SIZE - _SS_ALIGNSIZE
 	}
 
+	when ODIN_OS == .Linux {
+		sockaddr_storage :: struct {
+			ss_family:    sa_family_t,          /* [PSX] address family */
+			__ss_padding: [_SS_PADSIZE]c.char,
+			__ss_align:   c.uint64_t,           /* force structure storage alignment */
+		}
+
+		msghdr :: struct {
+			msg_name:       rawptr,    /* [PSX] optional address */
+			msg_namelen:    socklen_t, /* [PSX] size of address */
+			msg_iov:        [^]iovec,  /* [PSX] scatter/gather array */
+			msg_iovlen:     c.size_t,  /* [PSX] members in msg_iov */
+			msg_control:    rawptr,    /* [PSX] ancillary data */
+			msg_controllen: c.size_t,  /* [PSX] ancillary data buffer length */
+			msg_flags:      Msg_Flags, /* [PSX] flags on received message */
+		}
+	} else {
 		sockaddr_storage :: struct {
 			ss_len:     c.uint8_t,            /* address length */
 			ss_family:  sa_family_t,          /* [PSX] address family */
@@ -367,6 +400,8 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 			msg_controllen: socklen_t, /* [PSX] ancillary data buffer length */
 			msg_flags:      Msg_Flags, /* [PSX] flags on received message */
 		}
+	}
+
 
 	cmsghdr :: struct {
 		cmsg_len:   socklen_t, /* [PSX] data byte count, including cmsghdr */
@@ -458,6 +493,15 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 	// The maximum backlog queue length for listen().
 	SOMAXCONN :: 128
 
+	when ODIN_OS == .Linux {
+		MSG_CTRUNC    :: 0x007
+		MSG_DONTROUTE :: 0x004
+		MSG_EOR       :: 0x080
+		MSG_OOB       :: 0x001
+		MSG_PEEK      :: 0x002
+		MSG_TRUNC     :: 0x020
+		MSG_WAITALL   :: 0x100
+	} else {
 		MSG_CTRUNC    :: 0x20
 		MSG_DONTROUTE :: 0x4
 		MSG_EOR       :: 0x8
@@ -465,6 +509,7 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 		MSG_PEEK      :: 0x2
 		MSG_TRUNC     :: 0x10
 		MSG_WAITALL   :: 0x40
+	}
 
 	when ODIN_OS == .Darwin {
 		MSG_NOSIGNAL :: 0x80000
@@ -472,6 +517,8 @@ when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS
 		MSG_NOSIGNAL :: 0x00020000
 	} else when ODIN_OS == .NetBSD || ODIN_OS == .OpenBSD {
 		MSG_NOSIGNAL :: 0x0400
+	} else when ODIN_OS == .Linux {
+		MSG_NOSIGNAL  :: 0x4000
 	}
 
 	AF_INET   :: 2