library: fs: Factor out the Apple file time to attrlist code for reuse

Author: joshtriplett

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

@@ -1616,30 +1616,12 @@ impl File {
                 ))
             }
             target_vendor = "apple" => {
-                let mut buf = [mem::MaybeUninit::<libc::timespec>::uninit(); 3];
-                let mut num_times = 0;
-                let mut attrlist: libc::attrlist = unsafe { mem::zeroed() };
-                attrlist.bitmapcount = libc::ATTR_BIT_MAP_COUNT;
-                if times.created.is_some() {
-                    buf[num_times].write(file_time_to_timespec(times.created)?);
-                    num_times += 1;
-                    attrlist.commonattr |= libc::ATTR_CMN_CRTIME;
-                }
-                if times.modified.is_some() {
-                    buf[num_times].write(file_time_to_timespec(times.modified)?);
-                    num_times += 1;
-                    attrlist.commonattr |= libc::ATTR_CMN_MODTIME;
-                }
-                if times.accessed.is_some() {
-                    buf[num_times].write(file_time_to_timespec(times.accessed)?);
-                    num_times += 1;
-                    attrlist.commonattr |= libc::ATTR_CMN_ACCTIME;
-                }
+                let ta = TimesAttrlist::from_times(&times)?;
                 cvt(unsafe { libc::fsetattrlist(
                     self.as_raw_fd(),
-                    (&raw const attrlist).cast::<libc::c_void>().cast_mut(),
-                    buf.as_ptr().cast::<libc::c_void>().cast_mut(),
-                    num_times * size_of::<libc::timespec>(),
+                    ta.attrlist(),
+                    ta.times_buf(),
+                    ta.times_buf_size(),
                     0
                 ) })?;
                 Ok(())
@@ -1706,7 +1688,54 @@ fn file_time_to_timespec(time: Option<SystemTime>) -> io::Result<libc::timespec>
         )),
         None => Ok(libc::timespec { tv_sec: 0, tv_nsec: libc::UTIME_OMIT as _ }),
     }
-};
+}
+
+#[cfg(target_vendor = "apple")]
+struct TimesAttrlist {
+    buf: [mem::MaybeUninit<libc::timespec>; 3],
+    attrlist: libc::attrlist,
+    num_times: usize,
+}
+
+#[cfg(target_vendor = "apple")]
+impl TimesAttrlist {
+    fn from_times(times: &FileTimes) -> io::Result<Self> {
+        let mut this = Self {
+            buf: [mem::MaybeUninit::<libc::timespec>::uninit(); 3],
+            attrlist: unsafe { mem::zeroed() },
+            num_times: 0,
+        };
+        this.attrlist.bitmapcount = libc::ATTR_BIT_MAP_COUNT;
+        if times.created.is_some() {
+            this.buf[this.num_times].write(file_time_to_timespec(times.created)?);
+            this.num_times += 1;
+            this.attrlist.commonattr |= libc::ATTR_CMN_CRTIME;
+        }
+        if times.modified.is_some() {
+            this.buf[this.num_times].write(file_time_to_timespec(times.modified)?);
+            this.num_times += 1;
+            this.attrlist.commonattr |= libc::ATTR_CMN_MODTIME;
+        }
+        if times.accessed.is_some() {
+            this.buf[this.num_times].write(file_time_to_timespec(times.accessed)?);
+            this.num_times += 1;
+            this.attrlist.commonattr |= libc::ATTR_CMN_ACCTIME;
+        }
+        Ok(this)
+    }
+
+    fn attrlist(&self) -> *mut libc::c_void {
+        (&raw const self.attrlist).cast::<libc::c_void>().cast_mut()
+    }
+
+    fn times_buf(&self) -> *mut libc::c_void {
+        self.buf.as_ptr().cast::<libc::c_void>().cast_mut()
+    }
+
+    fn times_buf_size(&self) -> usize {
+        self.num_times * size_of::<libc::timespec>()
+    }
+}
 
 impl DirBuilder {
     pub fn new() -> DirBuilder {