Begin source reorganization with linux/can.h

This is a small module so it is easy to adapt to the future directory
structure.

Sources:

* https://github.com/torvalds/linux/blob/92a09c47464d040866cf2b4cd052bc60555185fb/include/uapi/linux/can.h
* https://github.com/torvalds/linux/blob/92a09c47464d040866cf2b4cd052bc60555185fb/include/uapi/linux/can/j1939.h
* https://github.com/torvalds/linux/blob/92a09c47464d040866cf2b4cd052bc60555185fb/include/uapi/linux/can/raw.h

Author: tgross35

src/lib.rs

@@ -22,6 +22,7 @@
 
 #[macro_use]
 mod macros;
+mod reorg;
 
 cfg_if! {
     if #[cfg(feature = "rustc-dep-of-std")] {
@@ -31,6 +32,9 @@ cfg_if! {
 
 pub use core::ffi::c_void;
 
+#[allow(unused_imports)] // needed while the module is empty on some platforms
+pub use reorg::*;
+
 cfg_if! {
     if #[cfg(windows)] {
         mod primitives;

src/new/linux_uapi/linux/can.rs

@@ -0,0 +1,136 @@
+//! Header: `uapi/linux/can.h`
+
+#[path = "can/j1939.rs"]
+pub(crate) mod j1939;
+#[path = "can/raw.rs"]
+pub(crate) mod raw;
+
+pub use j1939::*;
+pub use raw::*;
+
+use crate::prelude::*;
+
+pub const CAN_EFF_FLAG: canid_t = 0x80000000;
+pub const CAN_RTR_FLAG: canid_t = 0x40000000;
+pub const CAN_ERR_FLAG: canid_t = 0x20000000;
+
+pub const CAN_SFF_MASK: canid_t = 0x000007FF;
+pub const CAN_EFF_MASK: canid_t = 0x1FFFFFFF;
+pub const CAN_ERR_MASK: canid_t = 0x1FFFFFFF;
+pub const CANXL_PRIO_MASK: crate::canid_t = CAN_SFF_MASK;
+
+pub type canid_t = u32;
+
+pub const CAN_SFF_ID_BITS: c_int = 11;
+pub const CAN_EFF_ID_BITS: c_int = 29;
+pub const CANXL_PRIO_BITS: c_int = CAN_SFF_ID_BITS;
+
+pub type can_err_mask_t = u32;
+
+pub const CAN_MAX_DLC: c_int = 8;
+pub const CAN_MAX_DLEN: usize = 8;
+
+pub const CANFD_MAX_DLC: c_int = 15;
+pub const CANFD_MAX_DLEN: usize = 64;
+
+pub const CANXL_MIN_DLC: c_int = 0;
+pub const CANXL_MAX_DLC: c_int = 2047;
+pub const CANXL_MAX_DLC_MASK: c_int = 0x07FF;
+pub const CANXL_MIN_DLEN: usize = 1;
+pub const CANXL_MAX_DLEN: usize = 2048;
+
+s! {
+    #[repr(align(8))]
+    pub struct can_frame {
+        pub can_id: canid_t,
+        // FIXME(1.0): this field was renamed to `len` in Linux 5.11
+        pub can_dlc: u8,
+        __pad: u8,
+        __res0: u8,
+        pub len8_dlc: u8,
+        pub data: [u8; CAN_MAX_DLEN],
+    }
+}
+
+pub const CANFD_BRS: c_int = 0x01;
+pub const CANFD_ESI: c_int = 0x02;
+pub const CANFD_FDF: c_int = 0x04;
+
+s! {
+    #[repr(align(8))]
+    pub struct canfd_frame {
+        pub can_id: canid_t,
+        pub len: u8,
+        pub flags: u8,
+        __res0: u8,
+        __res1: u8,
+        pub data: [u8; CANFD_MAX_DLEN],
+    }
+}
+
+pub const CANXL_XLF: c_int = 0x80;
+pub const CANXL_SEC: c_int = 0x01;
+
+s! {
+    #[repr(align(8))]
+    pub struct canxl_frame {
+        pub prio: canid_t,
+        pub flags: u8,
+        pub sdt: u8,
+        pub len: u16,
+        pub af: u32,
+        pub data: [u8; CANXL_MAX_DLEN],
+    }
+}
+
+pub const CAN_MTU: usize = size_of::<can_frame>();
+pub const CANFD_MTU: usize = size_of::<canfd_frame>();
+pub const CANXL_MTU: usize = size_of::<canxl_frame>();
+// FIXME(offset_of): use `core::mem::offset_of!` once that is available
+// https://github.com/rust-lang/rfcs/pull/3308
+// pub const CANXL_HDR_SIZE: usize = core::mem::offset_of!(canxl_frame, data);
+pub const CANXL_HDR_SIZE: usize = 12;
+pub const CANXL_MIN_MTU: usize = CANXL_HDR_SIZE + 64;
+pub const CANXL_MAX_MTU: usize = CANXL_MTU;
+
+pub const CAN_RAW: c_int = 1;
+pub const CAN_BCM: c_int = 2;
+pub const CAN_TP16: c_int = 3;
+pub const CAN_TP20: c_int = 4;
+pub const CAN_MCNET: c_int = 5;
+pub const CAN_ISOTP: c_int = 6;
+pub const CAN_J1939: c_int = 7;
+pub const CAN_NPROTO: c_int = 8;
+
+pub const SOL_CAN_BASE: c_int = 100;
+
+s_no_extra_traits! {
+    pub struct sockaddr_can {
+        pub can_family: crate::sa_family_t,
+        pub can_ifindex: c_int,
+        pub can_addr: __c_anonymous_sockaddr_can_can_addr,
+    }
+
+    pub union __c_anonymous_sockaddr_can_can_addr {
+        pub tp: __c_anonymous_sockaddr_can_tp,
+        pub j1939: __c_anonymous_sockaddr_can_j1939,
+    }
+
+    pub struct __c_anonymous_sockaddr_can_tp {
+        pub rx_id: canid_t,
+        pub tx_id: canid_t,
+    }
+
+    pub struct __c_anonymous_sockaddr_can_j1939 {
+        pub name: u64,
+        pub pgn: u32,
+        pub addr: u8,
+    }
+
+    pub struct can_filter {
+        pub can_id: canid_t,
+        pub can_mask: canid_t,
+    }
+}
+
+pub const CAN_INV_FILTER: canid_t = 0x20000000;

src/new/linux_uapi/linux/can/j1939.rs

@@ -0,0 +1,60 @@
+//! `linux/can/j1939.h`
+
+pub use crate::linux::can::*;
+
+pub const J1939_MAX_UNICAST_ADDR: c_uchar = 0xfd;
+pub const J1939_IDLE_ADDR: c_uchar = 0xfe;
+pub const J1939_NO_ADDR: c_uchar = 0xff;
+pub const J1939_NO_NAME: c_ulong = 0;
+pub const J1939_PGN_REQUEST: c_uint = 0x0ea00;
+pub const J1939_PGN_ADDRESS_CLAIMED: c_uint = 0x0ee00;
+pub const J1939_PGN_ADDRESS_COMMANDED: c_uint = 0x0fed8;
+pub const J1939_PGN_PDU1_MAX: c_uint = 0x3ff00;
+pub const J1939_PGN_MAX: c_uint = 0x3ffff;
+pub const J1939_NO_PGN: c_uint = 0x40000;
+
+pub type pgn_t = u32;
+pub type priority_t = u8;
+pub type name_t = u64;
+
+pub const SOL_CAN_J1939: c_int = SOL_CAN_BASE + CAN_J1939;
+
+// FIXME(cleanup): these could use c_enum if it can accept anonymous enums.
+
+pub const SO_J1939_FILTER: c_int = 1;
+pub const SO_J1939_PROMISC: c_int = 2;
+pub const SO_J1939_SEND_PRIO: c_int = 3;
+pub const SO_J1939_ERRQUEUE: c_int = 4;
+
+pub const SCM_J1939_DEST_ADDR: c_int = 1;
+pub const SCM_J1939_DEST_NAME: c_int = 2;
+pub const SCM_J1939_PRIO: c_int = 3;
+pub const SCM_J1939_ERRQUEUE: c_int = 4;
+
+pub const J1939_NLA_PAD: c_int = 0;
+pub const J1939_NLA_BYTES_ACKED: c_int = 1;
+pub const J1939_NLA_TOTAL_SIZE: c_int = 2;
+pub const J1939_NLA_PGN: c_int = 3;
+pub const J1939_NLA_SRC_NAME: c_int = 4;
+pub const J1939_NLA_DEST_NAME: c_int = 5;
+pub const J1939_NLA_SRC_ADDR: c_int = 6;
+pub const J1939_NLA_DEST_ADDR: c_int = 7;
+
+pub const J1939_EE_INFO_NONE: c_int = 0;
+pub const J1939_EE_INFO_TX_ABORT: c_int = 1;
+pub const J1939_EE_INFO_RX_RTS: c_int = 2;
+pub const J1939_EE_INFO_RX_DPO: c_int = 3;
+pub const J1939_EE_INFO_RX_ABORT: c_int = 4;
+
+s! {
+    pub struct j1939_filter {
+        pub name: name_t,
+        pub name_mask: name_t,
+        pub pgn: pgn_t,
+        pub pgn_mask: pgn_t,
+        pub addr: u8,
+        pub addr_mask: u8,
+    }
+}
+
+pub const J1939_FILTER_MAX: c_int = 512;

src/new/linux_uapi/linux/can/raw.rs

@@ -0,0 +1,15 @@
+//! `linux/can/raw.h`
+
+pub use crate::linux::can::*;
+
+pub const SOL_CAN_RAW: c_int = SOL_CAN_BASE + CAN_RAW;
+pub const CAN_RAW_FILTER_MAX: c_int = 512;
+
+// FIXME(cleanup): use `c_enum!`, which needs to be adapted to allow omitting a type.
+pub const CAN_RAW_FILTER: c_int = 1;
+pub const CAN_RAW_ERR_FILTER: c_int = 2;
+pub const CAN_RAW_LOOPBACK: c_int = 3;
+pub const CAN_RAW_RECV_OWN_MSGS: c_int = 4;
+pub const CAN_RAW_FD_FRAMES: c_int = 5;
+pub const CAN_RAW_JOIN_FILTERS: c_int = 6;
+pub const CAN_RAW_XL_FRAMES: c_int = 7;

src/new/linux_uapi/linux/mod.rs

@@ -0,0 +1,4 @@
+//! The `linux` directory within `include/uapi` in the Linux source tree.
+
+pub(crate) mod can;
+pub use can::*;

src/new/linux_uapi/mod.rs

@@ -0,0 +1,4 @@
+//! This directory maps to `include/uapi` in the Linux source tree.
+
+pub(crate) mod linux;
+pub use linux::*;

src/new/mod.rs

@@ -0,0 +1,12 @@
+//! This module contains the future directory structure. If possible, new definitions should
+//! get added here.
+//!
+//! Eventually everything should be moved over, and we will move this directory to the top
+//! level in `src`.
+
+cfg_if! {
+    if #[cfg(target_os = "linux")] {
+        mod linux_uapi;
+        pub use linux_uapi::*;
+    }
+}