Rename FdTable to ResourceTable.

Add docs to src/resources.rs.

5 files changed, 142 insertions, 135 deletions

diff --git a/src/files.rs b/src/files.rs
deleted file mode 100644
index 64160bb84..000000000
--- a/src/files.rs
+++ /dev/null
@@ -1,119 +0,0 @@
-// Copyright 2018 the Deno authors. All rights reserved. MIT license.
-
-use futures;
-use futures::Poll;
-use std;
-use std::collections::HashMap;
-use std::io::Error;
-use std::io::{Read, Write};
-use std::sync::atomic::AtomicIsize;
-use std::sync::atomic::Ordering;
-use std::sync::Mutex;
-use tokio;
-use tokio::io::{AsyncRead, AsyncWrite};
-
-// These store Deno's file descriptors. These are not necessarally the operating
-// system ones.
-type FdTable = HashMap<i32, Repr>;
-
-lazy_static! {
-  // Starts at 3 because stdio is [0-2].
-  static ref NEXT_FD: AtomicIsize = AtomicIsize::new(3);
-  static ref FD_TABLE: Mutex<FdTable> = Mutex::new({
-    let mut m = HashMap::new();
-    // TODO Load these lazily during lookup?
-    m.insert(0, Repr::Stdin(tokio::io::stdin()));
-    m.insert(1, Repr::Stdout(tokio::io::stdout()));
-    m.insert(2, Repr::Stderr(tokio::io::stderr()));
-    m
-  });
-}
-
-// Internal representation of DFile.
-enum Repr {
-  Stdin(tokio::io::Stdin),
-  Stdout(tokio::io::Stdout),
-  Stderr(tokio::io::Stderr),
-  FsFile(tokio::fs::File),
-}
-
-// Abstract async file interface.
-// fd does not necessarally correspond to an OS fd.
-// Ideally in unix, if DFile represents an OS fd, it will be the same.
-pub struct DFile {
-  pub fd: i32,
-}
-
-impl Read for DFile {
-  fn read(&mut self, _buf: &mut [u8]) -> std::io::Result<usize> {
-    unimplemented!();
-  }
-}
-
-impl AsyncRead for DFile {
-  fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, Error> {
-    let mut table = FD_TABLE.lock().unwrap();
-    let maybe_repr = table.get_mut(&self.fd);
-    match maybe_repr {
-      None => panic!("bad fd"),
-      Some(repr) => match repr {
-        Repr::FsFile(ref mut f) => f.poll_read(buf),
-        Repr::Stdin(ref mut f) => f.poll_read(buf),
-        Repr::Stdout(_) | Repr::Stderr(_) => {
-          panic!("Cannot read from stdout/stderr")
-        }
-      },
-    }
-  }
-}
-
-impl Write for DFile {
-  fn write(&mut self, _buf: &[u8]) -> std::io::Result<usize> {
-    unimplemented!()
-  }
-
-  fn flush(&mut self) -> std::io::Result<()> {
-    unimplemented!()
-  }
-}
-
-impl AsyncWrite for DFile {
-  fn poll_write(&mut self, buf: &[u8]) -> Poll<usize, Error> {
-    let mut table = FD_TABLE.lock().unwrap();
-    let maybe_repr = table.get_mut(&self.fd);
-    match maybe_repr {
-      None => panic!("bad fd"),
-      Some(repr) => match repr {
-        Repr::FsFile(ref mut f) => f.poll_write(buf),
-        Repr::Stdout(ref mut f) => f.poll_write(buf),
-        Repr::Stderr(ref mut f) => f.poll_write(buf),
-        Repr::Stdin(_) => panic!("Cannot write to stdin"),
-      },
-    }
-  }
-
-  fn shutdown(&mut self) -> futures::Poll<(), std::io::Error> {
-    unimplemented!()
-  }
-}
-
-fn new_fd() -> i32 {
-  // TODO If on unix, just extract the real FD of fs_file.
-  // let fd = AsRawFd::as_raw_fd(fs_file.std());
-  let next_fd = NEXT_FD.fetch_add(1, Ordering::SeqCst);
-  next_fd as i32
-}
-
-pub fn add_fs_file(fs_file: tokio::fs::File) -> DFile {
-  let fd = new_fd();
-  let mut tg = FD_TABLE.lock().unwrap();
-  match tg.insert(fd, Repr::FsFile(fs_file)) {
-    Some(_) => panic!("There is already a file with that fd"),
-    None => DFile { fd },
-  }
-}
-
-pub fn lookup(fd: i32) -> Option<DFile> {
-  let table = FD_TABLE.lock().unwrap();
-  table.get(&fd).map(|_| DFile { fd })
-}
diff --git a/src/handlers.rs b/src/handlers.rs
index 1f861f000..db464f407 100644
--- a/src/handlers.rs
+++ b/src/handlers.rs
@@ -9,7 +9,6 @@ use isolate::IsolateState;
 use isolate::Op;
 use msg;
 
-use files;
 use flatbuffers::FlatBufferBuilder;
 use futures;
 use futures::future::poll_fn;
@@ -19,6 +18,7 @@ use hyper;
 use hyper::rt::{Future, Stream};
 use hyper::Client;
 use remove_dir_all::remove_dir_all;
+use resources;
 use std;
 use std::fs;
 #[cfg(any(unix))]
@@ -575,12 +575,12 @@ fn handle_open(
   let op = tokio::fs::File::open(filename)
     .map_err(|err| DenoError::from(err))
     .and_then(move |fs_file| -> OpResult {
-      let dfile = files::add_fs_file(fs_file);
+      let resource = resources::add_fs_file(fs_file);
       let builder = &mut FlatBufferBuilder::new();
       let msg = msg::OpenRes::create(
         builder,
         &msg::OpenResArgs {
-          fd: dfile.fd,
+          rid: resource.rid,
           ..Default::default()
         },
       );
@@ -604,16 +604,16 @@ fn handle_read(
 ) -> Box<Op> {
   let cmd_id = base.cmd_id();
   let msg = base.msg_as_read().unwrap();
-  let fd = msg.fd();
+  let rid = msg.rid();
 
-  match files::lookup(fd) {
+  match resources::lookup(rid) {
     None => odd_future(errors::new(
       errors::ErrorKind::BadFileDescriptor,
       String::from("Bad File Descriptor"),
     )),
-    Some(mut dfile) => {
+    Some(mut resource) => {
       let op = futures::future::poll_fn(move || {
-        let poll = dfile.poll_read(data);
+        let poll = resource.poll_read(data);
         poll
       }).map_err(|err| DenoError::from(err))
       .and_then(move |nread: usize| {
@@ -648,16 +648,16 @@ fn handle_write(
 ) -> Box<Op> {
   let cmd_id = base.cmd_id();
   let msg = base.msg_as_write().unwrap();
-  let fd = msg.fd();
+  let rid = msg.rid();
 
-  match files::lookup(fd) {
+  match resources::lookup(rid) {
     None => odd_future(errors::new(
       errors::ErrorKind::BadFileDescriptor,
       String::from("Bad File Descriptor"),
     )),
-    Some(mut dfile) => {
+    Some(mut resource) => {
       let op = futures::future::poll_fn(move || {
-        let poll = dfile.poll_write(data);
+        let poll = resource.poll_write(data);
         poll
       }).map_err(|err| DenoError::from(err))
       .and_then(move |bytes_written: usize| {
diff --git a/src/main.rs b/src/main.rs
index 01be538e1..d07eb5b07 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -23,13 +23,13 @@ extern crate ring;
 
 mod deno_dir;
 mod errors;
-mod files;
 mod flags;
 mod fs;
 pub mod handlers;
 mod http;
 mod isolate;
 mod libdeno;
+mod resources;
 mod tokio_util;
 mod version;
 
diff --git a/src/msg.fbs b/src/msg.fbs
index ef2f4946b..b9989c330 100644
--- a/src/msg.fbs
+++ b/src/msg.fbs
@@ -265,11 +265,11 @@ table Open {
 }
 
 table OpenRes {
-  fd: int;
+  rid: int;
 }
 
 table Read {
-  fd: int;
+  rid: int;
   // (ptr, len) is passed as second parameter to libdeno.send().
 }
 
@@ -279,7 +279,7 @@ table ReadRes {
 }
 
 table Write {
-  fd: int;
+  rid: int;
 }
 
 table WriteRes {
@@ -287,7 +287,7 @@ table WriteRes {
 }
 
 table Close {
-  fd: int;
+  rid: int;
 }
 
 root_type Base;
diff --git a/src/resources.rs b/src/resources.rs
new file mode 100644
index 000000000..940b14d21
--- /dev/null
+++ b/src/resources.rs
@@ -0,0 +1,126 @@
+// Copyright 2018 the Deno authors. All rights reserved. MIT license.
+
+// Think of Resources as File Descriptors. They are integers that are allocated
+// by the privlaged side of Deno to refer to various resources.  The simplest
+// example are standard file system files and stdio - but there will be other
+// resources added in the future that might not correspond to operating system
+// level File Descriptors. To avoid confusion we call them "resources" not "file
+// descriptors". This module implements a global resource table. Ops (AKA
+// handlers) look up resources by their integer id here.
+
+use futures;
+use futures::Poll;
+use std;
+use std::collections::HashMap;
+use std::io::Error;
+use std::io::{Read, Write};
+use std::sync::atomic::AtomicIsize;
+use std::sync::atomic::Ordering;
+use std::sync::Mutex;
+use tokio;
+use tokio::io::{AsyncRead, AsyncWrite};
+
+pub type ResourceId = i32; // Sometimes referred to RID.
+
+// These store Deno's file descriptors. These are not necessarily the operating
+// system ones.
+type ResourceTable = HashMap<ResourceId, Repr>;
+
+lazy_static! {
+  // Starts at 3 because stdio is [0-2].
+  static ref NEXT_RID: AtomicIsize = AtomicIsize::new(3);
+  static ref RESOURCE_TABLE: Mutex<ResourceTable> = Mutex::new({
+    let mut m = HashMap::new();
+    // TODO Load these lazily during lookup?
+    m.insert(0, Repr::Stdin(tokio::io::stdin()));
+    m.insert(1, Repr::Stdout(tokio::io::stdout()));
+    m.insert(2, Repr::Stderr(tokio::io::stderr()));
+    m
+  });
+}
+
+// Internal representation of Resource.
+enum Repr {
+  Stdin(tokio::io::Stdin),
+  Stdout(tokio::io::Stdout),
+  Stderr(tokio::io::Stderr),
+  FsFile(tokio::fs::File),
+}
+
+// Abstract async file interface.
+// Ideally in unix, if Resource represents an OS rid, it will be the same.
+pub struct Resource {
+  pub rid: ResourceId,
+}
+
+impl Read for Resource {
+  fn read(&mut self, _buf: &mut [u8]) -> std::io::Result<usize> {
+    unimplemented!();
+  }
+}
+
+impl AsyncRead for Resource {
+  fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, Error> {
+    let mut table = RESOURCE_TABLE.lock().unwrap();
+    let maybe_repr = table.get_mut(&self.rid);
+    match maybe_repr {
+      None => panic!("bad rid"),
+      Some(repr) => match repr {
+        Repr::FsFile(ref mut f) => f.poll_read(buf),
+        Repr::Stdin(ref mut f) => f.poll_read(buf),
+        Repr::Stdout(_) | Repr::Stderr(_) => {
+          panic!("Cannot read from stdout/stderr")
+        }
+      },
+    }
+  }
+}
+
+impl Write for Resource {
+  fn write(&mut self, _buf: &[u8]) -> std::io::Result<usize> {
+    unimplemented!()
+  }
+
+  fn flush(&mut self) -> std::io::Result<()> {
+    unimplemented!()
+  }
+}
+
+impl AsyncWrite for Resource {
+  fn poll_write(&mut self, buf: &[u8]) -> Poll<usize, Error> {
+    let mut table = RESOURCE_TABLE.lock().unwrap();
+    let maybe_repr = table.get_mut(&self.rid);
+    match maybe_repr {
+      None => panic!("bad rid"),
+      Some(repr) => match repr {
+        Repr::FsFile(ref mut f) => f.poll_write(buf),
+        Repr::Stdout(ref mut f) => f.poll_write(buf),
+        Repr::Stderr(ref mut f) => f.poll_write(buf),
+        Repr::Stdin(_) => panic!("Cannot write to stdin"),
+      },
+    }
+  }
+
+  fn shutdown(&mut self) -> futures::Poll<(), std::io::Error> {
+    unimplemented!()
+  }
+}
+
+fn new_rid() -> ResourceId {
+  let next_rid = NEXT_RID.fetch_add(1, Ordering::SeqCst);
+  next_rid as ResourceId
+}
+
+pub fn add_fs_file(fs_file: tokio::fs::File) -> Resource {
+  let rid = new_rid();
+  let mut tg = RESOURCE_TABLE.lock().unwrap();
+  match tg.insert(rid, Repr::FsFile(fs_file)) {
+    Some(_) => panic!("There is already a file with that rid"),
+    None => Resource { rid },
+  }
+}
+
+pub fn lookup(rid: ResourceId) -> Option<Resource> {
+  let table = RESOURCE_TABLE.lock().unwrap();
+  table.get(&rid).map(|_| Resource { rid })
+}