abi: Disable unsupported flags and functionality on MacOS

MacFUSE is a fork of FUSE version 19 with its own custom flags that
sometimes clash with later versions of FUSE. E.g. INIT_EXT flags clashes
with MacFUSE flag VOL_RENAME.

So to avoid confussion this change splits fuse_abi into fuse_abi_linux
and fuse_abi_macos and hopefully disables all functionality not
supported on MacOS. This applies both to MacFUSE and FUSE-T because
FUSE-T is built to be compatible with MacFUSE and not upstream FUSE.

Signed-off-by: Brian Olsen <[email protected]>

Author: griff

src/abi/fuse_abi.rs renamed to src/abi/fuse_abi_linux.rs

@@ -12,27 +12,16 @@ use std::mem;
 use bitflags::bitflags;
 use vm_memory::ByteValued;
 
-#[cfg(target_os = "linux")]
 pub use libc::{
     blksize_t, dev_t, ino64_t, mode_t, nlink_t, off64_t, pread64, preadv64, pwrite64, pwritev64,
     stat64, statvfs64,
 };
 
-#[cfg(target_os = "macos")]
-pub use libc::{
-    blksize_t, dev_t, ino_t as ino64_t, mode_t, nlink_t, off_t as off64_t, pread as pread64,
-    preadv as preadv64, pwrite as pwrite64, pwritev as pwritev64, stat as stat64,
-    statvfs as statvfs64,
-};
-
 /// Version number of this interface.
 pub const KERNEL_VERSION: u32 = 7;
 
 /// Minor version number of this interface.
-#[cfg(target_os = "linux")]
 pub const KERNEL_MINOR_VERSION: u32 = 33;
-#[cfg(target_os = "macos")]
-pub const KERNEL_MINOR_VERSION: u32 = 19;
 
 /// Init reply size is FUSE_COMPAT_INIT_OUT_SIZE
 pub const KERNEL_MINOR_VERSION_INIT_OUT_SIZE: u32 = 5;
@@ -571,25 +560,16 @@ pub struct Attr {
     pub atime: u64,
     pub mtime: u64,
     pub ctime: u64,
-    #[cfg(target_os = "macos")]
-    pub crtime: u64,
     pub atimensec: u32,
     pub mtimensec: u32,
     pub ctimensec: u32,
-    #[cfg(target_os = "macos")]
-    pub crtimensec: u32,
     pub mode: u32,
     pub nlink: u32,
     pub uid: u32,
     pub gid: u32,
     pub rdev: u32,
-    #[cfg(target_os = "macos")]
-    pub flags: u32,
     pub blksize: u32,
-    #[cfg(target_os = "linux")]
     pub flags: u32,
-    #[cfg(target_os = "macos")]
-    pub padding: u32,
 }
 unsafe impl ByteValued for Attr {}
 
@@ -611,39 +591,19 @@ impl Attr {
             atimensec: st.st_atime_nsec as u32,
             mtimensec: st.st_mtime_nsec as u32,
             ctimensec: st.st_ctime_nsec as u32,
-            #[cfg(target_os = "linux")]
             mode: st.st_mode,
-            #[cfg(target_os = "macos")]
-            mode: st.st_mode as u32,
             // In Linux st.st_nlink is u64 on x86_64 and powerpc64, and u32 on other architectures
-            // In macos, st_nlink is always u16
             // ref:
             // linux: https://github.com/rust-lang/rust/blob/1.69.0/library/std/src/os/linux/raw.rs#L333
-            // macos: https://github.com/rust-lang/rust/blob/1.69.0/library/std/src/os/macos/raw.rs#L44
-            #[cfg(any(
-                target_os = "macos",
-                all(
-                    target_os = "linux",
-                    any(target_arch = "x86_64", target_arch = "powerpc64")
-                )
-            ))]
+            #[cfg(any(target_arch = "x86_64", target_arch = "powerpc64"))]
             nlink: st.st_nlink as u32,
-            #[cfg(all(
-                target_os = "linux",
-                not(any(target_arch = "x86_64", target_arch = "powerpc64"))
-            ))]
+            #[cfg(not(any(target_arch = "x86_64", target_arch = "powerpc64")))]
             nlink: st.st_nlink,
             uid: st.st_uid,
             gid: st.st_gid,
             rdev: st.st_rdev as u32,
             blksize: st.st_blksize as u32,
             flags,
-            #[cfg(target_os = "macos")]
-            crtime: 0,
-            #[cfg(target_os = "macos")]
-            crtimensec: 0,
-            #[cfg(target_os = "macos")]
-            padding: 0,
         }
     }
 }
@@ -689,7 +649,6 @@ pub struct Kstatfs {
 unsafe impl ByteValued for Kstatfs {}
 
 impl From<statvfs64> for Kstatfs {
-    #[cfg(target_os = "linux")]
     fn from(st: statvfs64) -> Self {
         Kstatfs {
             blocks: st.f_blocks,
@@ -703,21 +662,6 @@ impl From<statvfs64> for Kstatfs {
             ..Default::default()
         }
     }
-
-    #[cfg(target_os = "macos")]
-    fn from(st: statvfs64) -> Self {
-        Kstatfs {
-            blocks: st.f_blocks as u64,
-            bfree: st.f_bfree as u64,
-            bavail: st.f_bavail as u64,
-            files: st.f_files as u64,
-            ffree: st.f_ffree as u64,
-            bsize: st.f_bsize as u32,
-            namelen: st.f_namemax as u32,
-            frsize: st.f_frsize as u32,
-            ..Default::default()
-        }
-    }
 }
 
 #[repr(C)]
@@ -885,10 +829,6 @@ unsafe impl ByteValued for MkdirIn {}
 #[derive(Debug, Default, Copy, Clone)]
 pub struct RenameIn {
     pub newdir: u64,
-    #[cfg(target_os = "macos")]
-    pub flags: u32,
-    #[cfg(target_os = "macos")]
-    pub padding: u32,
 }
 unsafe impl ByteValued for RenameIn {}
 
@@ -1059,10 +999,6 @@ unsafe impl ByteValued for SetxattrIn {}
 pub struct GetxattrIn {
     pub size: u32,
     pub padding: u32,
-    #[cfg(target_os = "macos")]
-    pub position: u32,
-    #[cfg(target_os = "macos")]
-    pub padding2: u32,
 }
 unsafe impl ByteValued for GetxattrIn {}
 
@@ -1377,24 +1313,15 @@ mod tests {
 
     #[test]
     fn test_struct_size() {
-        #[cfg(target_os = "linux")]
         assert_eq!(std::mem::size_of::<Attr>(), 88);
-        #[cfg(target_os = "macos")]
-        assert_eq!(std::mem::size_of::<Attr>(), 104);
         assert_eq!(std::mem::size_of::<Kstatfs>(), 80);
         assert_eq!(std::mem::size_of::<FileLock>(), 24);
-        #[cfg(target_os = "linux")]
         assert_eq!(std::mem::size_of::<EntryOut>(), 128);
-        #[cfg(target_os = "macos")]
-        assert_eq!(std::mem::size_of::<EntryOut>(), 144);
         assert_eq!(std::mem::size_of::<ForgetIn>(), 8);
         assert_eq!(std::mem::size_of::<ForgetOne>(), 16);
         assert_eq!(std::mem::size_of::<BatchForgetIn>(), 8);
         assert_eq!(std::mem::size_of::<GetattrIn>(), 16);
-        #[cfg(target_os = "linux")]
         assert_eq!(std::mem::size_of::<AttrOut>(), 104);
-        #[cfg(target_os = "macos")]
-        assert_eq!(std::mem::size_of::<AttrOut>(), 120);
         assert_eq!(std::mem::size_of::<MknodIn>(), 16);
         assert_eq!(std::mem::size_of::<MkdirIn>(), 8);
         assert_eq!(std::mem::size_of::<InHeader>(), 40);