std: bootstrapping libuv-based fileio in newrt... open & close

the test "touch"es a new file

Author: olsonjeffery

src/libstd/rt/uv/file.rs

@@ -11,30 +11,87 @@
 use prelude::*;
 use ptr::null;
 use libc::c_void;
-use rt::uv::{Request, NativeHandle, Loop, FsCallback};
+use rt::uv::{Request, NativeHandle, Loop, FsCallback,
+             status_to_maybe_uv_error_with_loop};
 use rt::uv::uvll;
 use rt::uv::uvll::*;
+use path::Path;
+use cast::transmute;
+use libc::{c_int};
 
 pub struct FsRequest(*uvll::uv_fs_t);
 impl Request for FsRequest;
 
+#[allow(non_camel_case_types)]
+pub enum UvFileFlag {
+    O_RDONLY,
+    O_WRONLY,
+    O_RDWR,
+    O_CREAT,
+    O_TRUNC
+}
+pub fn map_flag(v: UvFileFlag) -> int {
+    unsafe {
+        match v {
+            O_RDONLY => uvll::get_O_RDONLY() as int,
+            O_WRONLY => uvll::get_O_WRONLY() as int,
+            O_RDWR => uvll::get_O_RDWR() as int,
+            O_CREAT => uvll::get_O_CREAT() as int,
+            O_TRUNC => uvll::get_O_TRUNC() as int
+        }
+    }
+}
+
+pub struct RequestData {
+    complete_cb: Option<FsCallback>
+}
+
 impl FsRequest {
-    fn new() -> FsRequest {
+    pub fn new(cb: Option<FsCallback>) -> FsRequest {
         let fs_req = unsafe { malloc_req(UV_FS) };
         assert!(fs_req.is_not_null());
-        let fs_req = fs_req as *uvll::uv_write_t;
-        unsafe { uvll::set_data_for_req(fs_req, null::<()>()); }
-        NativeHandle::from_native_handle(fs_req)
+        let fs_req: FsRequest = NativeHandle::from_native_handle(fs_req);
+        fs_req.install_req_data(cb);
+        fs_req
+    }
+
+    pub fn install_req_data(&self, cb: Option<FsCallback>) {
+        let fs_req = (self.native_handle()) as *uvll::uv_write_t;
+        let data = ~RequestData {
+            complete_cb: cb
+        };
+        unsafe {
+            let data = transmute::<~RequestData, *c_void>(data);
+            uvll::set_data_for_req(fs_req, data);
+        }
     }
 
-    fn delete(self) {
-        unsafe { free_req(self.native_handle() as *c_void) }
+    fn get_req_data<'r>(&'r mut self) -> &'r mut RequestData {
+        unsafe {
+            let data = uvll::get_data_for_req((self.native_handle()));
+            let data = transmute::<&*c_void, &mut ~RequestData>(&data);
+            return &mut **data;
+        }
     }
 
-    fn open(&mut self, _loop_: &Loop, _cb: FsCallback) {
+    pub fn get_result(&mut self) -> c_int {
+        unsafe {
+            uvll::get_result_from_fs_req(self.native_handle())
+        }
     }
 
-    fn close(&mut self, _loop_: &Loop, _cb: FsCallback) {
+    pub fn get_loop(&self) -> Loop {
+        unsafe { Loop{handle:uvll::get_loop_from_fs_req(self.native_handle())} }
+    }
+
+    fn cleanup_and_delete(self) {
+        unsafe {
+            uvll::fs_req_cleanup(self.native_handle());
+            let data = uvll::get_data_for_uv_handle(self.native_handle());
+            let _data = transmute::<*c_void, ~RequestData>(data);
+            uvll::set_data_for_uv_handle(self.native_handle(), null::<()>());
+            free_req(self.native_handle() as *c_void)
+        }
     }
 }
 
@@ -46,3 +103,97 @@ impl NativeHandle<*uvll::uv_fs_t> for FsRequest {
         match self { &FsRequest(ptr) => ptr }
     }
 }
+
+pub struct FileDescriptor(c_int);
+impl FileDescriptor {
+    fn new(fd: c_int) -> FileDescriptor {
+        FileDescriptor(fd)
+    }
+
+    pub fn from_open_req(req: &mut FsRequest) -> FileDescriptor {
+        FileDescriptor::new(req.get_result())
+    }
+
+    pub fn open(loop_: Loop, path: Path, flags: int, mode: int,
+               cb: FsCallback) -> int {
+        let req = FsRequest::new(Some(cb));
+        path.to_str().to_c_str().with_ref(|p| unsafe {
+            uvll::fs_open(loop_.native_handle(),
+                          req.native_handle(), p, flags, mode, complete_cb) as int
+        })
+
+    }
+
+    fn close(self, loop_: Loop, cb: FsCallback) -> int {
+        let req = FsRequest::new(Some(cb));
+        unsafe {
+            uvll::fs_close(loop_.native_handle(), req.native_handle(),
+                           self.native_handle(), complete_cb) as int
+        }
+    }
+}
+extern fn complete_cb(req: *uv_fs_t) {
+    let mut req: FsRequest = NativeHandle::from_native_handle(req);
+    let loop_ = req.get_loop();
+    // pull the user cb out of the req data
+    let cb = {
+        let data = req.get_req_data();
+        assert!(data.complete_cb.is_some());
+        // option dance, option dance. oooooh yeah.
+        data.complete_cb.take_unwrap()
+    };
+    // in uv_fs_open calls, the result will be the fd in the
+    // case of success, otherwise it's -1 indicating an error
+    let result = req.get_result();
+    let status = status_to_maybe_uv_error_with_loop(
+        loop_.native_handle(), result);
+    // we have a req and status, call the user cb..
+    // only giving the user a ref to the FsRequest, as we
+    // have to clean it up, afterwards (and they aren't really
+    // reusable, anyways
+    cb(&mut req, status);
+    // clean up the req (and its data!) after calling the user cb
+    req.cleanup_and_delete();
+}
+
+impl NativeHandle<c_int> for FileDescriptor {
+    fn from_native_handle(handle: c_int) -> FileDescriptor {
+        FileDescriptor(handle)
+    }
+    fn native_handle(&self) -> c_int {
+        match self { &FileDescriptor(ptr) => ptr }
+    }
+}
+
+mod test {
+    use super::*;
+    //use rt::test::*;
+    use unstable::run_in_bare_thread;
+    use path::Path;
+    use rt::uv::Loop;
+
+    // this is equiv to touch, i guess?
+    fn file_test_touch_impl() {
+        debug!("hello?")
+        do run_in_bare_thread {
+            debug!("In bare thread")
+            let loop_ = Loop::new();
+            let flags = map_flag(O_RDWR) |
+                map_flag(O_CREAT) | map_flag(O_TRUNC);
+            do FileDescriptor::open(loop_, Path("./foo.txt"), flags, 0644)
+            |req, uverr| {
+                let loop_ = req.get_loop();
+                assert!(uverr.is_none());
+                let fd = FileDescriptor::from_open_req(req);
+                do fd.close(loop_) |_, uverr| {
+                    assert!(uverr.is_none());
+                };
+            };
+        }
+    }
+
+    #[test]
+    fn file_test_touch() {
+        file_test_touch_impl();
+    }
+}

src/libstd/rt/uv/mod.rs

@@ -53,7 +53,7 @@ use rt::io::IoError;
 
 //#[cfg(test)] use unstable::run_in_bare_thread;
 
-pub use self::file::FsRequest;
+pub use self::file::{FsRequest};
 pub use self::net::{StreamWatcher, TcpWatcher, UdpWatcher};
 pub use self::idle::IdleWatcher;
 pub use self::timer::TimerWatcher;
@@ -125,7 +125,7 @@ pub type ReadCallback = ~fn(StreamWatcher, int, Buf, Option<UvError>);
 pub type NullCallback = ~fn();
 pub type IdleCallback = ~fn(IdleWatcher, Option<UvError>);
 pub type ConnectionCallback = ~fn(StreamWatcher, Option<UvError>);
-pub type FsCallback = ~fn(FsRequest, Option<UvError>);
+pub type FsCallback = ~fn(&mut FsRequest, Option<UvError>);
 pub type TimerCallback = ~fn(TimerWatcher, Option<UvError>);
 pub type AsyncCallback = ~fn(AsyncWatcher, Option<UvError>);
 pub type UdpReceiveCallback = ~fn(UdpWatcher, int, Buf, SocketAddr, uint, Option<UvError>);
@@ -281,6 +281,20 @@ pub fn uv_error_to_io_error(uverr: UvError) -> IoError {
     }
 }
 
+/// Given a uv handle, convert a callback status to a UvError
+pub fn status_to_maybe_uv_error_with_loop(
+    loop_: *uvll::uv_loop_t,
+    status: c_int) -> Option<UvError> {
+    if status != -1 {
+        None
+    } else {
+        unsafe {
+            rtdebug!("loop: %x", loop_ as uint);
+            let err = uvll::last_error(loop_);
+            Some(UvError(err))
+        }
+    }
+}
 /// Given a uv handle, convert a callback status to a UvError
 pub fn status_to_maybe_uv_error<T, U: Watcher + NativeHandle<*T>>(handle: U,
                                                                  status: c_int) -> Option<UvError> {
@@ -290,9 +304,7 @@ pub fn status_to_maybe_uv_error<T, U: Watcher + NativeHandle<*T>>(handle: U,
         unsafe {
             rtdebug!("handle: %x", handle.native_handle() as uint);
             let loop_ = uvll::get_loop_for_uv_handle(handle.native_handle());
-            rtdebug!("loop: %x", loop_ as uint);
-            let err = uvll::last_error(loop_);
-            Some(UvError(err))
+            status_to_maybe_uv_error_with_loop(loop_, status)
         }
     }
 }

src/libstd/rt/uv/uvll.rs

@@ -617,7 +617,40 @@ pub unsafe fn ip6_port(addr: *sockaddr_in6) -> c_uint {
     return rust_uv_ip6_port(addr);
 }
 
+pub unsafe fn fs_open(loop_ptr: *uv_loop_t, req: *uv_fs_t, path: *c_char, flags: int, mode: int,
+                cb: *u8) -> c_int {
+    rust_uv_fs_open(loop_ptr, req, path, flags as c_int, mode as c_int, cb)
+}
+pub unsafe fn fs_close(loop_ptr: *uv_loop_t, req: *uv_fs_t, fd: c_int,
+                cb: *u8) -> c_int {
+    rust_uv_fs_close(loop_ptr, req, fd, cb)
+}
+pub unsafe fn fs_req_cleanup(req: *uv_fs_t) {
+    rust_uv_fs_req_cleanup(req);
+}
+
 // data access helpers
+pub unsafe fn get_O_RDONLY() -> c_int {
+    rust_uv_get_O_RDONLY()
+}
+pub unsafe fn get_O_WRONLY() -> c_int {
+    rust_uv_get_O_WRONLY()
+}
+pub unsafe fn get_O_RDWR() -> c_int {
+    rust_uv_get_O_RDWR()
+}
+pub unsafe fn get_O_CREAT() -> c_int {
+    rust_uv_get_O_CREAT()
+}
+pub unsafe fn get_O_TRUNC() -> c_int {
+    rust_uv_get_O_TRUNC()
+}
+pub unsafe fn get_result_from_fs_req(req: *uv_fs_t) -> c_int {
+    rust_uv_get_result_from_fs_req(req)
+}
+pub unsafe fn get_loop_from_fs_req(req: *uv_fs_t) -> *uv_loop_t {
+    rust_uv_get_loop_from_fs_req(req)
+}
 pub unsafe fn get_loop_for_uv_handle<T>(handle: *T) -> *c_void {
     #[fixed_stack_segment]; #[inline(never)];
 
@@ -784,6 +817,18 @@ extern {
     fn rust_uv_timer_start(timer_handle: *uv_timer_t, cb: uv_timer_cb, timeout: libc::uint64_t,
                            repeat: libc::uint64_t) -> c_int;
     fn rust_uv_timer_stop(handle: *uv_timer_t) -> c_int;
+    fn rust_uv_fs_open(loop_ptr: *c_void, req: *uv_fs_t, path: *c_char,
+                       flags: c_int, mode: c_int, cb: *u8) -> c_int;
+    fn rust_uv_fs_close(loop_ptr: *c_void, req: *uv_fs_t, fd: c_int,
+                        cb: *u8) -> c_int;
+    fn rust_uv_fs_req_cleanup(req: *uv_fs_t);
+    fn rust_uv_get_O_RDONLY() -> c_int;
+    fn rust_uv_get_O_WRONLY() -> c_int;
+    fn rust_uv_get_O_RDWR() -> c_int;
+    fn rust_uv_get_O_CREAT() -> c_int;
+    fn rust_uv_get_O_TRUNC() -> c_int;
+    fn rust_uv_get_result_from_fs_req(req: *uv_fs_t) -> c_int;
+    fn rust_uv_get_loop_from_fs_req(req: *uv_fs_t) -> *uv_loop_t;
 
     fn rust_uv_get_stream_handle_from_connect_req(connect_req: *uv_connect_t) -> *uv_stream_t;
     fn rust_uv_get_stream_handle_from_write_req(write_req: *uv_write_t) -> *uv_stream_t;

src/rt/rustrt.def.in

@@ -108,6 +108,16 @@ rust_uv_idle_delete
 rust_uv_idle_init
 rust_uv_idle_start
 rust_uv_idle_stop
+rust_uv_fs_open
+rust_uv_fs_close
+rust_uv_get_O_RDONLY
+rust_uv_get_O_WRONLY
+rust_uv_get_O_RDWR
+rust_uv_get_O_CREAT
+rust_uv_get_O_TRUNC
+rust_uv_get_result_from_fs_req
+rust_uv_get_loop_from_fs_req
+rust_uv_fs_req_cleanup
 rust_dbg_lock_create
 rust_dbg_lock_destroy
 rust_dbg_lock_lock