Auto merge of rust-lang#87810 - devnexen:haiku_os_simpl, r=Mark-Simulacrum

current_exe haiku code path simplification all of these part of libc

Author: bors

library/std/src/sys/unix/os.rs

@@ -388,46 +388,21 @@ pub fn current_exe() -> io::Result<PathBuf> {
 
 #[cfg(target_os = "haiku")]
 pub fn current_exe() -> io::Result<PathBuf> {
-    // Use Haiku's image info functions
-    #[repr(C)]
-    struct image_info {
-        id: i32,
-        type_: i32,
-        sequence: i32,
-        init_order: i32,
-        init_routine: *mut libc::c_void, // function pointer
-        term_routine: *mut libc::c_void, // function pointer
-        device: libc::dev_t,
-        node: libc::ino_t,
-        name: [libc::c_char; 1024], // MAXPATHLEN
-        text: *mut libc::c_void,
-        data: *mut libc::c_void,
-        text_size: i32,
-        data_size: i32,
-        api_version: i32,
-        abi: i32,
-    }
-
     unsafe {
-        extern "C" {
-            fn _get_next_image_info(
-                team_id: i32,
-                cookie: *mut i32,
-                info: *mut image_info,
-                size: i32,
-            ) -> i32;
-        }
-
-        let mut info: image_info = mem::zeroed();
+        let mut info: mem::MaybeUninit<libc::image_info> = mem::MaybeUninit::uninit();
         let mut cookie: i32 = 0;
         // the executable can be found at team id 0
-        let result =
-            _get_next_image_info(0, &mut cookie, &mut info, mem::size_of::<image_info>() as i32);
+        let result = libc::_get_next_image_info(
+            0,
+            &mut cookie,
+            info.as_mut_ptr(),
+            mem::size_of::<libc::image_info>(),
+        );
         if result != 0 {
             use crate::io::ErrorKind;
             Err(io::Error::new_const(ErrorKind::Uncategorized, &"Error getting executable path"))
         } else {
-            let name = CStr::from_ptr(info.name.as_ptr()).to_bytes();
+            let name = CStr::from_ptr((*info.as_ptr()).name.as_ptr()).to_bytes();
             Ok(PathBuf::from(OsStr::from_bytes(name)))
         }
     }