mman: Fix mman tests to be runnable

CHANGELOG.md

@@ -89,6 +89,9 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - Fixed potential undefined behavior in `Signal::try_from` on some platforms.
   (#[1484](https://github.com/nix-rust/nix/pull/1484))
 
+- Fixed mman tests to be runnable.
+  (#[1535](https://github.com/nix-rust/nix/pull/1535))
+
 ### Removed
 
 - Removed a couple of termios constants on redox that were never actually

test/sys/mod.rs

@@ -43,3 +43,6 @@ mod test_pthread;
 mod test_ptrace;
 #[cfg(any(target_os = "android", target_os = "linux"))]
 mod test_timerfd;
+#[cfg(any(target_os = "linux",
+          target_os = "netbsd"))]
+mod test_mman;

test/sys/test_mman.rs

@@ -1,16 +1,15 @@
-use nix::Error;
 use nix::libc::{c_void, size_t};
 use nix::sys::mman::{mmap, MapFlags, ProtFlags};
 
-#[cfg(target_os = "linux")]
+#[cfg(any(target_os = "linux", target_os = "netbsd"))]
 use nix::sys::mman::{mremap, MRemapFlags};
 
 #[test]
 fn test_mmap_anonymous() {
     let ref mut byte = unsafe {
         let ptr = mmap(std::ptr::null_mut(), 1,
                        ProtFlags::PROT_READ | ProtFlags::PROT_WRITE,
-                       MapFlags::MAP_PRIVATE | MapFlags::MAP_ANONYMOUS, -1, 0)
+                       MapFlags::MAP_PRIVATE | MapFlags::MAP_ANON, -1, 0)
                       .unwrap();
         *(ptr as * mut u8)
     };
@@ -26,7 +25,7 @@ fn test_mremap_grow() {
     let slice : &mut[u8] = unsafe {
         let mem = mmap(std::ptr::null_mut(), ONE_K,
                        ProtFlags::PROT_READ | ProtFlags::PROT_WRITE,
-                       MapFlags::MAP_ANONYMOUS | MapFlags::MAP_PRIVATE, -1, 0)
+                       MapFlags::MAP_ANON | MapFlags::MAP_PRIVATE, -1, 0)
                       .unwrap();
         std::slice::from_raw_parts_mut(mem as * mut u8, ONE_K)
     };
@@ -56,13 +55,19 @@ fn test_mremap_grow() {
 }
 
 #[test]
-#[cfg(any(target_os = "linux", target_os = "netbsd"))]
+// calling mremap to shrink could cause segfaults on some 32bit architectures likely due to qemu bug
+// refs: https://bugs.launchpad.net/qemu/+bug/1876373
+#[cfg(all(any(target_os = "linux", target_os = "netbsd"),
+          not(any(target_arch = "mips",
+                  target_arch = "mipsel",
+                  target_arch = "arm",
+                  target_arch = "armv7"))))]
 fn test_mremap_shrink() {
     const ONE_K : size_t = 1024;
     let slice : &mut[u8] = unsafe {
         let mem = mmap(std::ptr::null_mut(), 10 * ONE_K,
                        ProtFlags::PROT_READ | ProtFlags::PROT_WRITE,
-                       MapFlags::MAP_ANONYMOUS | MapFlags::MAP_PRIVATE, -1, 0)
+                       MapFlags::MAP_ANON | MapFlags::MAP_PRIVATE, -1, 0)
                       .unwrap();
         std::slice::from_raw_parts_mut(mem as * mut u8, ONE_K)
     };
@@ -75,12 +80,12 @@ fn test_mremap_shrink() {
         let mem = mremap(slice.as_mut_ptr() as * mut c_void, 10 * ONE_K, ONE_K,
                          MRemapFlags::empty(), None)
                       .unwrap();
-        // Since we didn't supply MREMAP_MAYMOVE, the address should be the
-        // same.
-        #[cfg(target_os = "linux")]
+        #[cfg(target_os = "netbsd")]
         let mem = mremap(slice.as_mut_ptr() as * mut c_void, 10 * ONE_K, ONE_K,
-                         MRemapFlags::MAP_FIXED), None)
+                         MRemapFlags::MAP_FIXED, None)
                       .unwrap();
+        // Since we didn't supply MREMAP_MAYMOVE, the address should be the
+        // same.
         assert_eq !(mem, slice.as_mut_ptr() as * mut c_void);
         std::slice::from_raw_parts_mut(mem as * mut u8, ONE_K)
     };