1 files changed, 81 insertions, 0 deletions
diff --git a/src/stub.rs b/src/stub.rs
new file mode 100644
index 0000000..3c6af0e
--- /dev/null
+++ b/src/stub.rs
@@ -0,0 +1,81 @@
+use std::fs::File;
+use std::io;
+
+// A stable alternative to https://doc.rust-lang.org/stable/std/primitive.never.html
+enum Never {}
+
+pub struct MmapInner {
+    never: Never,
+}
+
+impl MmapInner {
+    fn new() -> io::Result<MmapInner> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "platform not supported",
+        ))
+    }
+
+    pub fn map(_: usize, _: &File, _: u64, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn map_exec(_: usize, _: &File, _: u64, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn map_mut(_: usize, _: &File, _: u64, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn map_copy(_: usize, _: &File, _: u64, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn map_copy_read_only(_: usize, _: &File, _: u64, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn map_anon(_: usize, _: bool, _: bool) -> io::Result<MmapInner> {
+        MmapInner::new()
+    }
+
+    pub fn flush(&self, _: usize, _: usize) -> io::Result<()> {
+        match self.never {}
+    }
+
+    pub fn flush_async(&self, _: usize, _: usize) -> io::Result<()> {
+        match self.never {}
+    }
+
+    pub fn make_read_only(&mut self) -> io::Result<()> {
+        match self.never {}
+    }
+
+    pub fn make_exec(&mut self) -> io::Result<()> {
+        match self.never {}
+    }
+
+    pub fn make_mut(&mut self) -> io::Result<()> {
+        match self.never {}
+    }
+
+    #[inline]
+    pub fn ptr(&self) -> *const u8 {
+        match self.never {}
+    }
+
+    #[inline]
+    pub fn mut_ptr(&mut self) -> *mut u8 {
+        match self.never {}
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        match self.never {}
+    }
+}
+
+pub fn file_len(file: &File) -> io::Result<u64> {
+    Ok(file.metadata()?.len())
+}