Port mqueue to x32

Test fix obtained from
#1384 (comment)

Author: nabijaczleweli

src/mqueue.rs

@@ -5,7 +5,7 @@
 use crate::Result;
 use crate::errno::Errno;
 
-use libc::{self, c_char, c_long, mqd_t, size_t};
+use libc::{self, c_char, mqd_t, size_t};
 use std::ffi::CString;
 use crate::sys::stat::Mode;
 use std::mem;
@@ -34,11 +34,18 @@ pub struct MqAttr {
     mq_attr: libc::mq_attr,
 }
 
+// x32 compatibility
+// See https://sourceware.org/bugzilla/show_bug.cgi?id=21279
+#[cfg(all(target_arch = "x86_64", target_pointer_width = "32"))]
+pub type mq_attr_member_t = i64;
+#[cfg(not(all(target_arch = "x86_64", target_pointer_width = "32")))]
+pub type mq_attr_member_t = libc::c_long;
+
 impl MqAttr {
-    pub fn new(mq_flags: c_long,
-               mq_maxmsg: c_long,
-               mq_msgsize: c_long,
-               mq_curmsgs: c_long)
+    pub fn new(mq_flags: mq_attr_member_t,
+               mq_maxmsg: mq_attr_member_t,
+               mq_msgsize: mq_attr_member_t,
+               mq_curmsgs: mq_attr_member_t)
                -> MqAttr
     {
         let mut attr = mem::MaybeUninit::<libc::mq_attr>::uninit();
@@ -52,7 +59,7 @@ impl MqAttr {
         }
     }
 
-    pub fn flags(&self) -> c_long {
+    pub fn flags(&self) -> mq_attr_member_t {
         self.mq_attr.mq_flags
     }
 }
@@ -150,7 +157,7 @@ pub fn mq_setattr(mqd: mqd_t, newattr: &MqAttr) -> Result<MqAttr> {
 /// Returns the old attributes
 pub fn mq_set_nonblock(mqd: mqd_t) -> Result<MqAttr> {
     let oldattr = mq_getattr(mqd)?;
-    let newattr = MqAttr::new(c_long::from(MQ_OFlag::O_NONBLOCK.bits()),
+    let newattr = MqAttr::new(mq_attr_member_t::from(MQ_OFlag::O_NONBLOCK.bits()),
                               oldattr.mq_attr.mq_maxmsg,
                               oldattr.mq_attr.mq_msgsize,
                               oldattr.mq_attr.mq_curmsgs);

test/test_mq.rs

@@ -1,17 +1,15 @@
-use libc::c_long;
-
 use std::ffi::CString;
 use std::str;
 
 use nix::errno::Errno::*;
 use nix::Error::Sys;
-use nix::mqueue::{mq_open, mq_close, mq_send, mq_receive};
+use nix::mqueue::{mq_open, mq_close, mq_send, mq_receive, mq_attr_member_t};
 use nix::mqueue::{MqAttr, MQ_OFlag};
 use nix::sys::stat::Mode;
 
 #[test]
 fn test_mq_send_and_receive() {
-    const MSG_SIZE: c_long =  32;
+    const MSG_SIZE: mq_attr_member_t = 32;
     let attr =  MqAttr::new(0, 10, MSG_SIZE, 0);
     let mq_name= &CString::new(b"/a_nix_test_queue".as_ref()).unwrap();
 
@@ -43,7 +41,7 @@ fn test_mq_send_and_receive() {
 #[cfg(not(any(target_os = "netbsd")))]
 fn test_mq_getattr() {
     use nix::mqueue::mq_getattr;
-    const MSG_SIZE: c_long =  32;
+    const MSG_SIZE: mq_attr_member_t = 32;
     let initial_attr =  MqAttr::new(0, 10, MSG_SIZE, 0);
     let mq_name = &CString::new(b"/attr_test_get_attr".as_ref()).unwrap();
     let oflag = MQ_OFlag::O_CREAT | MQ_OFlag::O_WRONLY;
@@ -66,7 +64,7 @@ fn test_mq_getattr() {
 #[cfg_attr(any(target_arch = "mips", target_arch = "mips64"), ignore)]
 fn test_mq_setattr() {
     use nix::mqueue::{mq_getattr, mq_setattr};
-    const MSG_SIZE: c_long =  32;
+    const MSG_SIZE: mq_attr_member_t = 32;
     let initial_attr =  MqAttr::new(0, 10, MSG_SIZE, 0);
     let mq_name = &CString::new(b"/attr_test_get_attr".as_ref()).unwrap();
     let oflag = MQ_OFlag::O_CREAT | MQ_OFlag::O_WRONLY;
@@ -87,7 +85,7 @@ fn test_mq_setattr() {
     // O_NONBLOCK can be set (see tests below)
     assert_ne!(new_attr_get, new_attr);
 
-    let new_attr_non_blocking =  MqAttr::new(MQ_OFlag::O_NONBLOCK.bits() as c_long, 10, MSG_SIZE, 0);
+    let new_attr_non_blocking =  MqAttr::new(MQ_OFlag::O_NONBLOCK.bits() as mq_attr_member_t, 10, MSG_SIZE, 0);
     mq_setattr(mqd, &new_attr_non_blocking).unwrap();
     let new_attr_get = mq_getattr(mqd).unwrap();
 
@@ -103,7 +101,7 @@ fn test_mq_setattr() {
 #[cfg_attr(any(target_arch = "mips", target_arch = "mips64"), ignore)]
 fn test_mq_set_nonblocking() {
     use nix::mqueue::{mq_getattr, mq_set_nonblock, mq_remove_nonblock};
-    const MSG_SIZE: c_long =  32;
+    const MSG_SIZE: mq_attr_member_t = 32;
     let initial_attr =  MqAttr::new(0, 10, MSG_SIZE, 0);
     let mq_name = &CString::new(b"/attr_test_get_attr".as_ref()).unwrap();
     let oflag = MQ_OFlag::O_CREAT | MQ_OFlag::O_WRONLY;
@@ -116,7 +114,7 @@ fn test_mq_set_nonblocking() {
     let mqd = r.unwrap();
     mq_set_nonblock(mqd).unwrap();
     let new_attr = mq_getattr(mqd);
-    assert_eq!(new_attr.unwrap().flags(), MQ_OFlag::O_NONBLOCK.bits() as c_long);
+    assert_eq!(new_attr.unwrap().flags(), MQ_OFlag::O_NONBLOCK.bits() as mq_attr_member_t);
     mq_remove_nonblock(mqd).unwrap();
     let new_attr = mq_getattr(mqd);
     assert_eq!(new_attr.unwrap().flags(), 0);
@@ -127,7 +125,7 @@ fn test_mq_set_nonblocking() {
 #[cfg(not(any(target_os = "netbsd")))]
 fn test_mq_unlink() {
     use nix::mqueue::mq_unlink;
-    const MSG_SIZE: c_long =  32;
+    const MSG_SIZE: mq_attr_member_t = 32;
     let initial_attr =  MqAttr::new(0, 10, MSG_SIZE, 0);
     let mq_name_opened = &CString::new(b"/mq_unlink_test".as_ref()).unwrap();
     let mq_name_not_opened = &CString::new(b"/mq_unlink_test".as_ref()).unwrap();