add fs

l0dable/src/fs.rs

+use core::str::from_utf8_unchecked;
+use core::mem::uninitialized;
+use super::bindings::*;
+
+type Result<T> = core::result::Result<T, Error>;
+
+#[derive(Copy, Clone, Debug)]
+pub struct Error {
+    pub errno: i32,
+}
+
+impl Error {
+    fn check<F: FnOnce() -> i32>(f: F) -> Result<i32> {
+        let res = f();
+        if res >= 0 {
+            Ok(res)
+        } else {
+            Err(res.into())
+        }
+    }
+}
+
+impl From<i32> for Error {
+    fn from(errno: i32) -> Self {
+        Error { errno }
+    }
+}
+
+pub fn read_dir(path: &str) -> Result<ReadDir> {
+    let pathbuf = crate::str_to_cstr(path);
+    Error::check(|| unsafe {
+        epic_file_opendir(pathbuf.as_ptr())
+    }).map(|fd| ReadDir { fd })
+}
+
+pub struct ReadDir {
+    fd: i32,
+}
+
+impl<'a> Iterator for ReadDir {
+    type Item = Result<DirStat>;
+    fn next(&mut self) -> Option<Self::Item> {
+        let mut entry: epic_stat = unsafe { uninitialized() };
+        let res = unsafe { epic_file_readdir(self.fd, &mut entry as *mut epic_stat as *mut _) };
+        if res < 0 {
+            return Some(Err(res.into()));
+        }
+        match entry.type_ {
+            epic_stat_type::None => None,
+            _ => Some(Ok(DirStat { entry })),
+        }
+    }
+}
+
+#[repr(u8)]
+#[derive(Copy, Clone)]
+pub enum epic_stat_type {
+    None = 0,
+    File = 1,
+    Dir = 2,
+}
+
+#[repr(packed)]
+#[derive(Copy, Clone)]
+pub struct epic_stat {
+    /// not u32 as generated by bindgen
+    pub type_: epic_stat_type,
+    pub size: u32,
+    pub name: [super::ctypes::c_char; 256usize],
+    pub _reserved: [u8; 12usize],
+}
+
+pub struct DirStat {
+    entry: epic_stat,
+}
+
+impl DirStat {
+    pub fn is_file(&self) -> bool {
+        match self.entry.type_ {
+            epic_stat_type::File => true,
+            _ => false,
+        }
+    }
+
+    pub fn is_dir(&self) -> bool {
+        match self.entry.type_ {
+            epic_stat_type::Dir => true,
+            _ => false,
+        }
+    }
+
+    /// FIXME: corrupt
+    pub fn size(&self) -> u32 {
+        self.entry.size
+    }
+
+    pub fn name(&self) -> &str {
+        let len = self.entry.name.iter().position(|b| *b == 0)
+            .unwrap_or(0);
+        unsafe {
+            from_utf8_unchecked(&self.entry.name[0..len])
+        }
+    }
+}
+
+pub fn rename(from: &str, to: &str) -> Result<()> {
+    let frombuf = crate::str_to_cstr(from);
+    let tobuf = crate::str_to_cstr(to);
+    Error::check(|| unsafe {
+        epic_file_rename(frombuf.as_ptr(), tobuf.as_ptr())
+    }).map(|_| ())
+}
+
+pub struct File {
+    pub fd: i32,
+}
+
+impl File {
+    pub fn open(path: &str) -> Result<File> {
+        let pathbuf = crate::str_to_cstr(path);
+        let modebuf = b"r\0";
+        Error::check(|| unsafe {
+            epic_file_open(pathbuf.as_ptr(), modebuf.as_ptr())
+        }).map(|fd| File { fd })
+    }
+
+    pub fn read<'a>(&mut self, buf: &'a mut [u8]) -> Result<&'a [u8]> {
+        let bytes = Error::check(|| unsafe {
+            epic_file_read(self.fd, buf.as_ptr() as *mut _, buf.len())
+        })? as usize;
+        Ok(&buf[0..bytes])
+    }
+}
+
+impl Drop for File {
+    fn drop(&mut self) {
+        unsafe { epic_file_close(self.fd); }
+    }
+}

l0dable/src/lib.rs

@@ -86,3 +86,4 @@ mod bme680;
 pub use bme680::BME680;
 mod bhi160;
 pub use bhi160::{Sensor as BHI160, Accelerometer, Orientation, Gyroscope, SensorData as BHI160Data};
+pub mod fs;