chore: clippy cleanup ptr_eq (#2618)

* chore: clippy cleanup ptr_eq

* chore: allow deprecated SOCK_PACKET

Author: SteveLauC

src/sys/mman.rs

@@ -439,7 +439,7 @@ pub unsafe fn mmap<F: AsFd>(
         libc::mmap(ptr, length.into(), prot.bits(), flags.bits(), fd, offset)
     };
 
-    if ret == libc::MAP_FAILED {
+    if std::ptr::eq(ret, libc::MAP_FAILED) {
         Err(Errno::last())
     } else {
         // SAFETY: `libc::mmap` returns a valid non-null pointer or `libc::MAP_FAILED`, thus `ret`
@@ -471,7 +471,7 @@ pub unsafe fn mmap_anonymous(
         libc::mmap(ptr, length.into(), prot.bits(), flags.bits(), -1, 0)
     };
 
-    if ret == libc::MAP_FAILED {
+    if std::ptr::eq(ret, libc::MAP_FAILED) {
         Err(Errno::last())
     } else {
         // SAFETY: `libc::mmap` returns a valid non-null pointer or `libc::MAP_FAILED`, thus `ret`
@@ -520,7 +520,7 @@ pub unsafe fn mremap(
         )
     };
 
-    if ret == libc::MAP_FAILED {
+    if std::ptr::eq(ret, libc::MAP_FAILED) {
         Err(Errno::last())
     } else {
         // SAFETY: `libc::mremap` returns a valid non-null pointer or `libc::MAP_FAILED`, thus `ret`

test/sys/test_sockopt.rs

@@ -241,6 +241,8 @@ fn test_so_type_unknown() {
     use nix::errno::Errno;
 
     require_capability!("test_so_type", CAP_NET_RAW);
+    // SOCK_PACKET is deprecated, but since it is used for testing here, we allow it
+    #[allow(deprecated)]
     let raw_fd = unsafe { libc::socket(libc::AF_PACKET, libc::SOCK_PACKET, 0) };
     assert!(raw_fd >= 0, "Error opening socket: {}", nix::Error::last());
     let sockfd = unsafe { OwnedFd::from_raw_fd(raw_fd) };